WorldWideScience

Sample records for groundwater resource observed

  1. Canada's groundwater resources

    National Research Council Canada - National Science Library

    Rivera, Alfonso

    2014-01-01

    Groundwater is essential for life in arid and semiarid region. It is also important in humid regions, and is one of the fundamental requirements for the maintenance of natural landscapes and aquatic ecosystem...

  2. Dynamic evaluation of groundwater resources in Zhangye Basin

    Institute of Scientific and Technical Information of China (English)

    LiNa Mi; HongLang Xiao; ZhengLiang Yin; ShengChun Xiao

    2016-01-01

    Groundwater resource is vital to the sustainable development of socio-economics in arid and semi-arid regions of Northwest China. An estimation of the groundwater resources variation in Zhangye Basin was made during 1985–2013 based on long-term groundwater observation data and geostatistical method. The results show that from 1985 to 2013, groundwater storage exhibited tremendous dissimilarity on temporal and spatial scale for the whole Zhangye Basin, especially before and after implementation of the water diversion policy. Trend of groundwater storage varied from quick to slow decline or increase. The accumulative groundwater storage decreased nearly 47.52×108 m3, and annual average depletion rate reached 1.64×108 m3/a. Among which, the accumulative groundwater storage of the river and well water mixed irrigation district decreased by 37.48×108 m3, accounting for about 78.87% of the total groundwater depletion of the Zhangye Basin. Accumulative depletion of groundwater storage varied in respective irrigation districts. Though groundwater resources depletion rate slowed down from 2005, the overall storage in the whole basin and re-spective districts during 1985–2013 was still in a severe deficit such that, the groundwater resource was in a rather negative balance, which could threaten the local aquifer. This is the joint effect of climate change and human activities, however human activities, such as water diversion policy and groundwater exploitation, became increasingly intense. Our research results could provide a reasonable estimation for the groundwater balance in Zhangye Basin, providing a scientific basis for water resources unified planning and, this method can provide a relatively reliable way of estimation for large scale groundwater resources.

  3. Global depletion of groundwater resources

    NARCIS (Netherlands)

    Wada, Y.; Beek, L.P.H. van; van Kempen, C.M.; Reckman, J.W.T.M.; Vasak, S.; Bierkens, M.F.P.

    2010-01-01

    In regions with frequent water stress and large aquifer systems groundwater is often used as an additional water source. If groundwater abstraction exceeds the natural groundwater recharge for extensive areas and long times, overexploitation or persistent groundwater depletion occurs. Here we provid

  4. Analysis of groundwater recoverable resource by numerical method in Linfen Basin of Shanxi, North China

    Institute of Scientific and Technical Information of China (English)

    Liping BAI; Yeyao WANG; Jinsheng WANG

    2008-01-01

    Calculation of the groundwater recoverable resource is the main part of groundwater resource evaluation. The three-dimensional groundwater flow model in Linfen Basin was established by GMS software. Then the numerical model was calibrated by observed groundwater level from February to December in 2 000. Based on the calibrated model, the groundwater recoverable resource is calculated. The simulation result shows that under the given value of the groundwater recoverable resource, the groundwater level would decrease significantly in the first 1 000 days, while the water level would drop slowly in 1 000 to 2 000 days, and the water level change tend to be stable after 2000 days.

  5. Groundwater Resources: Investigation and Development

    Science.gov (United States)

    Anderson, Mary P.

    A glance through the table of contents of this volume might suggest that it is yet another introductory text on principles of groundwater hydrology. All of the usual basic topics are covered including definitions of terms and concepts, aquifer types, drilling methods, and pumping tests. But partly because this book is intended for practicing groundwater consultants rather than students, other less elementary topics such as environmental isotope techniques, geochemical methods, interpretation and utilization of spring flow, geophysical methods, and groundwater balances are also included.According to the preface, ‘practical applicability’ is stressed ‘to show how groundwater investigations should be conducted using a systematic, well-directed effort’ and to describe ‘… what to do, what to avoid, and what kind of results one can reasonably expect …’ While this book was published as part of a series of monographs on water pollution, it is more in the nature of a handbook than a true monograph. That is, it is not an in-depth treatment of a single topic but presents a broad introduction to the ways in

  6. Impacts of Groundwater Pumping on Regional and Global Water Resources

    Science.gov (United States)

    Wada, Yoshihide

    2016-01-01

    Except frozen water in ice and glaciers (68%), groundwater is the world's largest distributed store of freshwater (30%), and has strategic importance to global food and water security. In this chapter, the most recent advances assessing human impact on regional and global groundwater resources are reviewed. This chapter critically evaluates the recently advanced modeling approaches quantifying the effect of groundwater pumping in regional and global groundwater resources and the evidence of feedback to the Earth system including sea-level rise associated with groundwater use. At last, critical challenges and opportunities are identified in the use of groundwater to adapt to growing food demand and uncertain climate.

  7. Integrated groundwater resource management in Indus Basin using satellite gravimetry and physical modeling tools.

    Science.gov (United States)

    Iqbal, Naveed; Hossain, Faisal; Lee, Hyongki; Akhter, Gulraiz

    2017-03-01

    Reliable and frequent information on groundwater behavior and dynamics is very important for effective groundwater resource management at appropriate spatial scales. This information is rarely available in developing countries and thus poses a challenge for groundwater managers. The in situ data and groundwater modeling tools are limited in their ability to cover large domains. Remote sensing technology can now be used to continuously collect information on hydrological cycle in a cost-effective way. This study evaluates the effectiveness of a remote sensing integrated physical modeling approach for groundwater management in Indus Basin. The Gravity Recovery and Climate Experiment Satellite (GRACE)-based gravity anomalies from 2003 to 2010 were processed to generate monthly groundwater storage changes using the Variable Infiltration Capacity (VIC) hydrologic model. The groundwater storage is the key parameter of interest for groundwater resource management. The spatial and temporal patterns in groundwater storage (GWS) are useful for devising the appropriate groundwater management strategies. GRACE-estimated GWS information with large-scale coverage is valuable for basin-scale monitoring and decision making. This frequently available information is found useful for the identification of groundwater recharge areas, groundwater storage depletion, and pinpointing of the areas where groundwater sustainability is at risk. The GWS anomalies were found to favorably agree with groundwater model simulations from Visual MODFLOW and in situ data. Mostly, a moderate to severe GWS depletion is observed causing a vulnerable situation to the sustainability of this groundwater resource. For the sustainable groundwater management, the region needs to implement groundwater policies and adopt water conservation techniques.

  8. Guide to Louisiana's ground-water resources

    Science.gov (United States)

    Stuart, C.G.; Knochenmus, D.D.; McGee, B.D.

    1994-01-01

    Ground water is one of the most valuable and abundant natural resources of Louisiana. Of the 4-.4 million people who live in the State, 61 percent use ground water as a source for drinking water. Most industrial and rural users and half of the irrigation users in the State rely on ground water. Quantity, however, is not the only aspect that makes ground water so valuable; quality also is important for its use. In most areas, little or no water treatment is required for drinking water and industrial purposes. Knowledge of Louisiana's ground-water resources is needed to ensure proper development and protection of this valuable resource. This report is designed to inform citizens about the availability and quality of ground water in Louisiana. It is not intended as a technical reference; rather, it is a guide to ground water and the significant role this resource plays in the state. Most of the ground water that is used in the State is withdrawn from 13 aquifers and aquifer systems: the Cockfield, Sparta, and Carrizo-Wilcox aquifersin northern Louisiana; Chicot aquifer system, Evangeline aquifer, Jasper aquifer system, and Catahoula aquifer in central and southwestern Louisiana; the Chicot equivalent, Evangeline equivalent, and Jasper equivalent aquifer systems in southeastern Louisiana; and the MississippiRiver alluvial, Red River alluvial, and upland terrace aquifers that are statewide. Ground water is affected by man's activities on the land surface, and the major ground-water concerns in Louisiana are: (1) contamination from surface disposal of hazardous waste, agricultural chemicals, and petroleum products; (2) contamination from surface wastes and saltwater through abandoned wells; (3) saltwater encroachment; and (4) local overdevelopment. Information about ground water in Louisiana is extensive and available to the public. Several State and Federal agencies provide published and unpublished material upon request.

  9. Global governance principles for the sustainable development of groundwater resources

    NARCIS (Netherlands)

    Conti, K.I.; Gupta, J.

    2016-01-01

    A normative framework for the governance of groundwater is emerging at the global level. However, existing analyses have not comprehensively covered all the governance texts that have a bearing on transboundary groundwater resources or looked at them from the perspective of sustainable groundwater g

  10. Groundwater Systems and Resources in the Ordos Basin, China

    Institute of Scientific and Technical Information of China (English)

    HOU Guangcai; LIANG Yongping; SU Xiaosi; ZHAO Zhenghong; TAO Zhengping; YIN Lihe; YANG Yuncheng; WANG Xiaoyong

    2008-01-01

    The Ordos Basin is.a large-scalesedimentary basin in northwestern China. The hydrostratigraphic units from bottom to top are pre-Cambrian metamorphic rocks, Lower Paleozoic carbonate rocks, Upper Paleozoic to Mesozoic clastic rocks and Cenozoic deposits. The total thickness is up to 6000 m. Three groundwater systems are present in the Ordos Basin, based on the geological settings, I.e. The karst groundwater system, the Cretaceous dastic groundwater system and the Quaternary groundwater system. This paper describes systematically the groundwater flow patterns of each system and overall assessment of groundwater resources.

  11. The interplay of snow, surface water, and groundwater reservoirs for integrated water resources management

    Science.gov (United States)

    Rajagopal, S.; Huntington, J.

    2015-12-01

    Changes in climate, growth in population and economy have increased the reliance on groundwater to augment supplies of surface water across the world, and especially the Western United States. Martis Valley, a high altitude, snow dominated watershed in the Sierra Nevada, California has both surface (river/reservoir) and groundwater resources that are utilized to meet demands within the valley. The recent drought and changing precipitation type (less snow, more rain) has stressed the regional surface water supply and has increased the reliance on groundwater pumping. The objective of this paper is to quantify how changes in climate and depletion of snow storage result in decreased groundwater recharge and increased groundwater use, and to assess if increased surface water storage can mitigate impacts to groundwater under historic and future climate conditions. These objectives require knowledge on the spatiotemporal distribution of groundwater recharge, discharge, and surface and groundwater interactions. We use a high resolution, physically-based integrated surface and groundwater model, GSFLOW, to identify key mechanisms that explain recent hydrologic changes in the region. The model was calibrated using a multi-criteria approach to various historical observed hydrologic fluxes (streamflow and groundwater pumping) and states (lake stage, groundwater head, snow cover area). Observations show that while groundwater use in the basin has increased significantly since the 1980's, it still remains a relatively minor component of annual consumptive water use. Model simulations suggest that changes from snow to rain will lead to increases in Hortonian and Dunnian runoff, and decreases in groundwater recharge and discharge to streams, which could have a greater impact on groundwater resources than increased pumping. These findings highlight the necessity of an integrated approach for evaluating natural and anthropogenic impacts on surface and groundwater resources.

  12. Groundwater resource-directed measures software

    African Journals Online (AJOL)

    2006-07-21

    Jul 21, 2006 ... 1Institute for Groundwater Studies, University of the Free State, PO Box 339, Bloemfontein, 9300, South Africa ... In this paper the methods developed for the GRDM .... The geothermal gradient for groundwater, that is, the.

  13. Sustainability analysis of groundwater resources in a coastal aquifer, Alabama

    Science.gov (United States)

    Liu, Jie; Rich, Kendall; Zheng, Chunmiao

    2008-03-01

    Fort Morgan Peninsula is an attached portion of a dynamic barrier complex in the northern Gulf of Mexico and is a large tourist area that brings in a significant amount of revenue for Alabama. Many of the hotels and tourist attractions depend on the groundwater as their water supply. The over-withdrawal of groundwater and saltwater intrustion will have a negative impact on the ecology, tourism and economy if groundwater resources are not properly monitored and managed. In this study a calibrated groundwater flow model was used to analyze the sustainability of groundwater resources at Fort Morgan Peninsula. Detailed flow budgets were prepared to check the various components of inflow and outflow under different water use and climatic conditions. The results indicated the locations where groundwater was over-pumped and subjected to saltwater intrusion, or will be subjected to saltwater intrusion under a range of projected water use and climatic conditions.

  14. Surficial Geologic Map and Groundwater Resources of Woodstock, Vermont

    Data.gov (United States)

    Vermont Center for Geographic Information — Digital data from VG06-5 DeSimone, D., 2006,�Surficial Geologic Map and Groundwater Resources of Woodstock, Vermont: Vermont Geological Survey Open-File Report...

  15. Groundwater resources monitoring and population displacement in northern Uganda

    Science.gov (United States)

    Chalikakis, K.; Hammache, Y.; Nawa, A.; Slinski, K.; Petropoulos, G.; Muteesasira, A.

    2009-04-01

    provide a guideline for a sustainable exploration of groundwater resources within the investigated regions, relating to population movements and potential of aquifers. To achieve these objectives a) groundwater samples are collected and analyzed (microbiologically, chemically and physically) from all types of water points, boreholes and "protected" springs, during rainy, dry and intermediate seasons, b) a network of piezometers is being installed for monitoring groundwater level, and comparison with available rainfall data will define groundwater balance. During these steps results are compared with the population's displacement and density in order to quantify the consequences towards the groundwater resources. Preliminary results after microbiological analysis show the inadequacy of traditional "protected" springs in providing safe water. Feacal pollution is observed in "protected" springs even though it was not being observed before and during rehabilitation. It is mainly due to recent population concentration around the available water resources and the lack of comprehensive hydrogeological study of the functioning of the near surface aquifers. Accordingly all operations concerning spring rehabilitation are on hold. No evidence regarding microbiological contamination was found from borehole water samples. However, high concentration in ferrous iron and total iron was found in several boreholes. Concentrations in the water of weathered bedrock are expected and specific treatment is necessary.

  16. Quality of groundwater resources in Afghanistan.

    Science.gov (United States)

    Hayat, Ehsanullah; Baba, Alper

    2017-07-01

    Water is the main source of energy production and economy in Afghanistan where agriculture accounts for more than 50% of the country's gross domestic product (GDP). Access to safe drinking water is still a problem in the country, which has caused different health issues and even child mortality especially in rural areas. Groundwater is the main source of drinking water in the country. However, little knowledge is available about the quality of groundwater throughout the entire country, and its quality has not been investigated extensively yet like in other countries in the world. While most people think that consuming groundwater is a reliable and safe source of drinking water for health, the United Nations (UN) agencies report various kinds of waterborne diseases and even child mortalities due to drinking water quality in the country. In this article, significant geogenic and anthropogenic factors that play a vital role in groundwater contamination of the country are identified and explained. Different geogenic contaminations such as arsenic, fluoride, sulfate, and boron occur in several areas of Afghanistan that have a direct effect on human health. The water quality mapping for Afghanistan is completed for half of the country, which shows that groundwater is plagued by high levels of fluoride and arsenic in some areas. The water quality mapping of the other half of the country cannot be completed due to security concerns currently. Also, there are different kinds of waterborne diseases such as diarrhea, cholera, and dysentery that can be seen in different parts of the country because of anthropogenic activities which continuously deteriorate groundwater.

  17. Groundwater: A Vital Resource. Student Activities.

    Science.gov (United States)

    Taylor, Carla, Ed.

    Twenty-three activities dealing with various aspects of groundwater are provided in this manual. The activities are arranged under four headings: (1) the water cycle; (2) water distribution in soils (considering such topics as calculating water table depth and purifying water by filtering); (3) water quality (considering such topics as acid rain,…

  18. Global assessments of submarine groundwater discharge and groundwater resources under the pressures of humanity and climate change

    Science.gov (United States)

    Taniguchi, M.; Burnett, W. C.; Aureli, A.

    2006-12-01

    We report here the global-scale assessment of both fresh and saline groundwater discharges based solely on observational data. Prior estimates have been limited to various water balance and hydrodynamic modeling calculations and range over orders of magnitude. Our observations suggest the global volumes of fresh groundwater discharge and recirculated seawater per unit shoreline length depending on the distance from the shoreline, precipitation, and seawater depth. On a world-wide scale, these flows are compared with the global river discharge. We show via automated measurements that precipitation and wave pumping are important controls of terrestrial (fresh) and marine-induced (recirculated seawater) subterranean flows, respectively. The Groundwater Resources Assessment under the Pressures of Humanity and Climate Changes (GRAPHIC) Project, an initiative of UNESCO International Hydrological Programme (IHP), seeks to improve the understanding and management of groundwater as a vital contributor to the global water cycle, ecosystems and communities, under changing climatic and anthropomorphic regimes. GRAPHIC focuses on variations of the flows, stocks, and quality of groundwater recharge, discharge and storage and on groundwater-related management and policy (http://www.chikyu.ac.jp/USE/GRAPHIC/GRAPHIC.htm). This GRAPHIC project will deal with groundwater resources assessment and future forecasting under the various pressures of humanity and climate changes. The structure of the GRAPHIC project has been divided into; (A) Subjects; thematic, cross-region issues, (B) Methods; methodological approaches (1:Database and Monitoring, 2:Satelite GRACE (Gravity Recovery and Climate Experiment), 3:Modeling and Simulation, 4:Paleohydrology), and (C) Regions; representative geographical areas, where pilot studies will be made.

  19. Fresh groundwater resources in a large sand replenishment

    Science.gov (United States)

    Huizer, Sebastian; Oude Essink, Gualbert H. P.; Bierkens, Marc F. P.

    2016-08-01

    The anticipation of sea-level rise and increases in extreme weather conditions has led to the initiation of an innovative coastal management project called the Sand Engine. In this pilot project a large volume of sand (21.5 million m3) - also called sand replenishment or nourishment - was placed on the Dutch coast. The intention is that the sand is redistributed by wind, current, and tide, reinforcing local coastal defence structures and leading to a unique, dynamic environment. In this study we investigated the potential effect of the long-term morphological evolution of the large sand replenishment and climate change on fresh groundwater resources. The potential effects on the local groundwater system were quantified with a calibrated three-dimensional (3-D) groundwater model, in which both variable-density groundwater flow and salt transport were simulated. Model simulations showed that the long-term morphological evolution of the Sand Engine results in a substantial growth of fresh groundwater resources, in all adopted climate change scenarios. Thus, the application of a local sand replenishment could provide coastal areas the opportunity to combine coastal protection with an increase of the local fresh groundwater availability.

  20. Appraisal of groundwater resources in an island condition

    Indian Academy of Sciences (India)

    N C Mondal; V S Singh; D V Sarwade; M V Nandakumar

    2009-06-01

    A group of 36 coral islands is being scattered in the Arabian Sea of the western coast of India. On such islands,groundwater is the only source of fresh water for the islanders.The demand for groundwater is increasing every year due to growing population and urbanization.On the other side the peculiar hydrologic,geologic and geomorphic features restrict the availability of groundwater. Thus a proper understanding of the groundwater condition is important in order to meet this increasing demand and also to formulate future development and management strategies.Detailed hydrogeological,geophysical and hydrochemical studies had been carried out to identify potential fresh groundwater resources and quantify vulnerable parts of Andrott Island,Union Territory of Lakshadweep.Systematic collection and analysis of hydrological,geophysical and hydrochemical data gives an early signal of deterioration in groundwater quality in the peripheral parts of eastern and western coasts of this island and it suggests immediate measures for arresting the deterioration in groundwater quality as well as augmentation for restoration of aquifer in some parts of the island.

  1. Study on protection and reclamation for the groundwater resources in Busan area

    Energy Technology Data Exchange (ETDEWEB)

    Sung, Ig-Hwan; Cho, Byong-Wook; Lee, Byung-Dae [Korea Institute of Geology Mining and Materials, Taejon (KR)] (and others)

    1999-12-01

    This research was carried out to investigate the protection of contaminated groundwater and reclamation in the Pusan area. Groundwater Busan city is highly subjected to groundwater contamination due to its unfavorable geographical features; it is located in the estuaries of the Nakdong river, most of the urban area are composed of highlands, and the large population resides in the downhill. Heavy pumping and deterioration of groundwater are currently found to be significant compared to other major cities, resulting in shortage of water resources and contamination of groundwater. The first step of the research aims at investigating hydrogeological features which includes analysis of climate and hydrologic data, investigation of geology and structural pattern, acquisition of hydrological data, inspection of wells, measurement of groundwater level, analysis of water samples, investigation of groundwater contamination, isotope analysis, and monitoring water level by automated data logger to identify seawater intrusion. The second step is to simulate the two-dimensional flow model after construction of the database. Aside from this, abandoned wells were transformed into observation wells. An effort for remedy of contaminated groundwater was made and the water quality was constantly monitored to improve the deteriorated water to the drinking water. Kriging analysis and geostatistical analysis were carried out in order to verify the effect of seawater intrusion, showing that there is no clear evidence of seawater intrusion. Instead, it is clear that groundwater in the inland district was preferentially contaminated by pollutants originated from human activities. Based on the two-dimensional flow model, only 0.021 m{sup 3} may be allocated to each person a day from public wells for emergency. In order to ensure that protection and remediation of groundwater of the Busan area are able to accomplish, well-controlled management of aquifer systems needs to be maintained and

  2. Groundwater resource exploration in Salem district, Tamil Nadu using GIS and remote sensing

    Science.gov (United States)

    Maheswaran, G.; Selvarani, A. Geetha; Elangovan, K.

    2016-03-01

    Since last decade, the value per barrel of potable groundwater has outpaced the value of a barrel of oil in many areas of the world. Hence, proper assessment of groundwater potential and management practices are the needs of the day. Establishing relationship between remote sensing data and hydrologic phenomenon can maximize the efficiency of water resources development projects. Present study focuses on groundwater potential assessment in Salem district, Tamil Nadu to investigate groundwater resource potential. At the same, all thematic layers important from ground water occurrence and movement point of view were digitized and integrated in the GIS environment. The weights of different parameters/themes were computed using weighed index overlay analysis (WIOA), analytic hierarchy process (AHP) and fuzzy logic technique. Through this integrated GIS analysis, groundwater prospect map of the study area was prepared qualitatively. Field verification at observation wells was used to verify identified potential zones and depth of water measured at observation wells. Generated map from weighed overlay using AHP performed very well in predicting the groundwater surface and hence this methodology proves to be a promising tool for future.

  3. Ground-water resources of Cambodia

    Science.gov (United States)

    Rasmussen, William Charles; Bradford, Gary M.

    1977-01-01

    available information is on the central lowlands and contiguous low plateaus, as the mountainous areas on the west and the high plateaus on the east are relatively unexplored with respect to their ground-water availability. No persistent artesian aquifer has been identified nor have any large potential ground-water sources been found .although much of the country yet remains to be explored by test drilling. Well irrigation for garden produce is feasible on a modest scale in many localities throughout Cambodia. It does not seem likely, however, that large-scale irrigation from wells will come about in the future. Ground water may be regarded as a widely available supplemental source to surface water for domestic, small-scale industrial, and irrigation use.

  4. ANALYSIS AND CALCULATION OF REGULATED WATER RESOURCES OF GROUNDWATER RESERVOIR

    Institute of Scientific and Technical Information of China (English)

    DAI Chang-lei; CHI Bao-ming; GAO Shu-qin

    2005-01-01

    Groundwater reservoir is a kind of important engineering, which can optimize water resources arran-gement by means of artificial regulation. Regulated water is the blood and value performance of groundwater reser-voir. To resolve the problem of real-time quantification of regulated water, the paper analyzed sources and composi-tions of regulated water in detail. Then, under the conditions of satisfying water demand inside research area, the pa-per analyzed quantity available and regulation coefficient of different regulated water and established a formula tocalculate regulated water. At last, based on a pore groundwater reservoir in the middle reaches of the Yinma River,Jilin Province, the paper calculated regulated water with the formula and the result shows that the method is feasible.With some constraint conditions, the formula can be adopted in other similar areas.

  5. On the scope and management of pesticide pollution of Swedish groundwater resources: The Scanian example.

    Science.gov (United States)

    Åkesson, Maria; Sparrenbom, Charlotte J; Dahlqvist, Peter; Fraser, Stephen J

    2015-04-01

    Twenty-three south-Swedish public supply wells were studied to assess pesticide pollution of regional groundwater resources. Relations between pesticide occurrence, hydrogeology, and land use were analyzed using Kohonen's Self-Organizing Maps approach. Pesticides are demonstrated to be substantially present in regional groundwater, with detections in 18 wells. Concentrations above the drinking water threshold are confirmed for nine wells. Observations indicate considerable urban influence, and lagged effects of past, less restricted use. Modern, oxic waters from shallow, unconfined, unconsolidated or fracture-type bedrock aquifers appear particularly vulnerable. Least affected waters appear primarily associated with deeper wells, anoxic conditions, and more confined sediment aquifers lacking urban influence. Comprehensive, standardized monitoring of pesticides in groundwater need to be implemented nationwide to enable sound assessments of pollution status and trends, and to develop sound groundwater management plans in accordance with the Water Framework Directive. Further, existing water protection areas and associated regulations need to be reassessed.

  6. Fresh Groundwater Resources in Georgia and Management Problems

    Science.gov (United States)

    Gaprindashvili, George; Gaprindashvili, Merab

    2015-04-01

    Fresh water represents conditioned factor for human body's life. That's why the superiority of drinking water is recognized as human body's priority according to the international declarations. World is experiencing deficit of quality water. Natural Disasters caused by the pollution of the fresh groundwater is also very painful and acute, because it needed more time, more material and financial means for the liquidation of their results, and what the most important practically is, it is impossible to renew the initial natural conditions completely. All these conditions that the rational use of fresh groundwater passed by the interests of separate countries and became worldwide, international problem - fresh water became as considerable raw material for the worlds import and export. The fresh groundwater place the important role among the water recourses of Georgia. Their existing is considerably connected to the development of industry and agriculture, also with water supply issue of populated area. Groundwater management requires precise knowledge of sources (aquifers). Monitoring of Georgia's most important aquifers started many years ago and has provided large amount of data. This was interrupted at the beginning of the 1990s. It could be noted that fresh water existing in the country is distinguished with high quality. According to the mineralization and temperature parameters groundwater is generally divided into the following groups: 1) Fresh drinking waters (mineralization not exceeding 1.0 g/l); 2) Mineral waters (mineralization over 1.0 g/l); 3) Thermal waters -- healing (20˚C - 35˚C), Geothermal (40˚C - 108˚C). Below we present briefly review about the situation of fresh groundwater resources, started recovery of groundwater monitoring network and the analysis of the management problems.

  7. Application of Bayesian Decision Networks for sustainable groundwater resources management in semi-arid regions

    Science.gov (United States)

    Mohajerani, Hadis; Casper, Markus; Kholghi, Majid; Mosaedi, Abolfazl; Farmani, Raziyeh; Saadoddin, Amir; Meftah Halaghi, Mehdi

    2017-04-01

    This paper presents management of groundwater resource using a Bayesian Decision Network (BDN). The Kordkooy region in North East of Iran has been selected as study area. The region has been divided to three parts based on Transmissivity (T) and Electrical Conductivity (EC) values. The BDN parameters (prior probabilities and Conditional Probability Tables (CPTs) have been identified for each of the three zones. Three groups of management scenarios have been developed based on the two decision variables including "Crop pattern" and "Domestic water demand" across the three zones of the study area: 1) status quo management for all three zones representing current conditions. 2) the effect of change in cropping pattern on management endpoints and 3) the effect of increasing domestic water demand on management endpoints in the future. The outcomes arising from implementing each scenario have been predicted using the BDN for each of the zones. Results reveal that probability of drawdown in groundwater levels of southern areas is relatively high compared with other zones. Groundwater withdrawal from northern and northwestern areas of the study area should be limited due to the groundwater quality problems associated with shallow groundwater of these two zones. The ability of the Bayesian Decision Network to take into account key uncertainties in natural resources and performing a meaningful analysis in cases where there is not vast amount of information and observed data available -even based partly on expert opinion- emphasizes the advantage of this approach in groundwater resources management process, as limited data availability was a serious problem faced by groundwater resources of the study area.

  8. Can we monitor groundwater head variation from space? Coupling ERS spaceborne microwave observations to groundwater dynamics

    NARCIS (Netherlands)

    Sutanudjaja, E. H.; de Jong, S. M.; van Geer, F. C.; Bierkens, M. F. P.

    2012-01-01

    The objective of this study is to investigate whether the time series of a remote sensing based soil moisture product, referred as the European Remote Sensing Soil Water Index (ERS SWI), correlates to in-situ observations of groundwater heads; and can thus be used for groundwater head prediction. As

  9. Karst groundwater: a challenge for new resources

    Science.gov (United States)

    Bakalowicz, Michel

    2005-03-01

    Karst aquifers have complex and original characteristics which make them very different from other aquifers: high heterogeneity created and organised by groundwater flow; large voids, high flow velocities up to several hundreds of m/h, high flow rate springs up to some tens of m3/s. Different conceptual models, known from the literature, attempt to take into account all these particularities. The study methods used in classical hydrogeology—bore hole, pumping test and distributed models—are generally invalid and unsuccessful in karst aquifers, because the results cannot be extended to the whole aquifer nor to some parts, as is done in non-karst aquifers. Presently, karst hydrogeologists use a specific investigation methodology (described here), which is comparable to that used in surface hydrology. Important points remain unsolved. Some of them are related to fundamental aspects suc h as the void structure - only a conduit network, or a conduit network plus a porous matrix -, the functioning - threshold effects and non-linearities -, the modeling of the functioning - double or triple porosity, or viscous flow in conduits - and of karst genesis. Some other points deal with practical aspects, such as the assessment of aquifer storage capacity or vulnerability, or the prediction of the location of highly productive zones. Los acuíferos kársticos tienen características originales y complejas que los hacen muy diferentes de otros acuíferos: alta heterogeneidad creada y organizada por el flujo de agua subterránea, espacios grandes, velocidades altas de flujo de hasta varios cientos de m/h, manantiales con ritmo alto de flujo de hasta algunas decenas de m3/s. Diferentes modelos conceptuales que se conocen en la literatura tratan de tomar en cuenta todas estas particularidades. Los métodos de estudio usados en hidrogeología clásica- pozos, pruebas de bombeo y modelos distribuidos- son generalmente inválidos y no exitosos en acuíferos kársticos, debido a que

  10. A simulation/optimization model for groundwater resources management in the Afram Plains area, Ghana

    Science.gov (United States)

    Yidana, S.M.

    2008-01-01

    A groundwater flow simulation model was developed using available hydrogeo logical data to A groundwater flow simulation model was developed using available hydrogeological data to describe groundwater flow in the Afram Plains area. A nonlinear optimization model was then developed and solved for the management of groundwater resources to meet irrigation and household needs. The objective was to maximize groundwater extraction for irrigation activities from the shallow aquifers of the southern Voltaian Sedimentary Basin that underly the area This would improve food security, raise the standard of living and ultimately alleviate poverty in the Afram Plains. The calibrated flow model is in tandem with the general hydrochemical evolution of groundwater in the area and fits the observed data with about a 98% degree of confidence. Groundwater resources may not be the limiting factor in the development of irrigated agriculture. Groundwater has tremendous potential to meet current and future irrigation needs. It was determined from this study that profit from maize irrigation in the Afram Plains area could rise from US$301, 000 in 2007 to over US$3.5 million by the end of the last management period (2013) as irrigation practice is improved, and the economic strength to increase the acreage for irrigation improves. Even with these margins of profit, the drawdown constraint was not reached in any of the management periods. It is expected that rechargefrom the irrigation water would reclaim the lost hydraulic head. The single significant constraint was the amount of land area that could be developed for irrigation in the area. The profit obtained per unit cubic meter of water used also improved over the same management period.

  11. Groundwater resource exploration in Salem district, Tamil Nadu using GIS and remote sensing

    Indian Academy of Sciences (India)

    G Maheswaran; A Geetha Selvarani; K Elangovan

    2016-03-01

    Since last decade, the value per barrel of potable groundwater has outpaced the value of a barrel of oil in many areas of the world. Hence, proper assessment of groundwater potential and management practices are the needs of the day. Establishing relationship between remote sensing data and hydrologic phenomenon can maximize the efficiency of water resources development projects. Present study focuses on groundwater potential assessment in Salem district, Tamil Nadu to investigate groundwater resourcepotential. At the same, all thematic layers important from ground water occurrence and movement point of view were digitized and integrated in the GIS environment. The weights of different parameters/themes were computed using weighed index overlay analysis (WIOA), analytic hierarchy process (AHP) andfuzzy logic technique. Through this integrated GIS analysis, groundwater prospect map of the study area was prepared qualitatively. Field verification at observation wells was used to verify identified potential zones and depth of water measured at observation wells. Generated map from weighed overlay using AHP performed very well in predicting the groundwater surface and hence this methodology proves to be a promising tool for future.

  12. GPS Application for Groundwater Resource Assessment, Hermanus, South Africa

    Science.gov (United States)

    Hartnady, C.; Mlisa, A.; Wonnacott, R.; Calais, E.

    2009-04-01

    TrigNet (http://www.trignet.co.za/footprint/home.jsp) is a network of permanent continuously operating GPS (cGPS) base stations distributed throughout South Africa at approximately 200 - 300 km spacing. Data from 21 of the stations is continuously streamed to the TrigNet control centre in the offices of the Chief Directorate: Surveys and Mapping, from where it is made available within 30 minutes after each hour for 24 hours a day. All stations record 1-second epoch data on both GPS frequencies (L1 and L2) through geodetic-standard choke ring antennas. The real-time Trignet station HERM is situated in the grounds of the Hermanus Magnetic Observatory (HMO), in a coastal town about 100 km SW of the City of Cape Town. The Overstrand Municipality of the Greater Hermanus Area has embarked on a major groundwater development to augment the water supply. As a foundation for sustainable management of the groundwater resource, a detailed monitoring programme was developed for a better understanding of the hydraulic system, and of the interconnections between surface water, the shallow primary aquifer and the remarkable, deep, fractured-rock (FR) aquifer of the Table Mountain Group (TMG), which underlies a large part of the Western Cape province in South Africa. A thick, extensive FR aquifer system like the ~1 km thick Peninsula Aquifer in the TMG provides an opportunity for fundamental advances in understanding interactions between fluid flow and mechanical deformation, through analysis of the "hydro-mechanical" coupling in FR permeability, fluid transport and deep storage in FR porosity. Present knowledge of skeletal-framework compressibility, the main factor in specific storage, is based on published data from similar rocks elsewhere. Up-scaling from dry-sample laboratory measurements of elastic properties of borehole-core samples at ~10-cm scale to saturated rock volumes on 100- to 1000-m scale, is methodologically problematic. Measuring directly the compaction of, and

  13. Groundwater Storage Changes: Present Status from GRACE Observations

    Science.gov (United States)

    Chen, Jianli; Famigliett, James S.; Scanlon, Bridget R.; Rodell, Matthew

    2016-03-01

    Satellite gravity measurements from the Gravity Recovery and Climate Experiment (GRACE) provide quantitative measurement of terrestrial water storage (TWS) changes with unprecedented accuracy. Combining GRACE-observed TWS changes and independent estimates of water change in soil and snow and surface reservoirs offers a means for estimating groundwater storage change. Since its launch in March 2002, GRACE time-variable gravity data have been successfully used to quantify long-term groundwater storage changes in different regions over the world, including northwest India, the High Plains Aquifer and the Central Valley in the USA, the North China Plain, Middle East, and southern Murray-Darling Basin in Australia, where groundwater storage has been significantly depleted in recent years (or decades). It is difficult to rely on in situ groundwater measurements for accurate quantification of large, regional-scale groundwater storage changes, especially at long timescales due to inadequate spatial and temporal coverage of in situ data and uncertainties in storage coefficients. The now nearly 13 years of GRACE gravity data provide a successful and unique complementary tool for monitoring and measuring groundwater changes on a global and regional basis. Despite the successful applications of GRACE in studying global groundwater storage change, there are still some major challenges limiting the application and interpretation of GRACE data. In this paper, we present an overview of GRACE applications in groundwater studies and discuss if and how the main challenges to using GRACE data can be addressed.

  14. Groundwater Storage Changes: Present Status from GRACE Observations

    Science.gov (United States)

    Chen, Jianli; Famiglietti, James S.; Scanlon, Bridget R.; Rodell, Matthew

    2015-01-01

    Satellite gravity measurements from the Gravity Recovery and Climate Experiment (GRACE) provide quantitative measurement of terrestrial water storage (TWS) changes with unprecedented accuracy. Combining GRACE-observed TWS changes and independent estimates of water change in soil and snow and surface reservoirs offers a means for estimating groundwater storage change. Since its launch in March 2002, GRACE time-variable gravity data have been successfully used to quantify long-term groundwater storage changes in different regions over the world, including northwest India, the High Plains Aquifer and the Central Valley in the USA, the North China Plain, Middle East, and southern Murray-Darling Basin in Australia, where groundwater storage has been significantly depleted in recent years (or decades). It is difficult to rely on in situ groundwater measurements for accurate quantification of large, regional-scale groundwater storage changes, especially at long timescales due to inadequate spatial and temporal coverage of in situ data and uncertainties in storage coefficients. The now nearly 13 years of GRACE gravity data provide a successful and unique complementary tool for monitoring and measuring groundwater changes on a global and regional basis. Despite the successful applications of GRACE in studying global groundwater storage change, there are still some major challenges limiting the application and interpretation of GRACE data. In this paper, we present an overview of GRACE applications in groundwater studies and discuss if and how the main challenges to using GRACE data can be addressed.

  15. Improved water resource management using three dimensional groundwater modelling for a highly complex environmental

    Science.gov (United States)

    Moeck, Christian; Affolter, Annette; Radny, Dirk; Auckenthaler, Adrian; Huggenberger, Peter; Schirmer, Mario

    2017-04-01

    Proper allocation and management of groundwater is an important and critical challenge under rising water demands of various environmental sectors but good groundwater quality is often limited because of urbanization and contamination of aquifers. Given the predictive capability of groundwater models, they are often the only viable means of providing input to water management decisions. However, modelling flow and transport processes can be difficult due to their unknown subsurface heterogeneity and typically unknown distribution of contaminants. As a result water resource management tasks are based on uncertain assumption on contaminants patterns and this uncertainty is typically not incorporated into the assessment of risks associated with different proposed management scenarios. A three-dimensional groundwater model was used to improve water resource management for a study area, where drinking water production is close to different former landfills and industrial areas. To avoid drinking water contamination, artificial groundwater recharge with surface water into the gravel aquifer is used to create a hydraulic barrier between contaminated sites and drinking water extraction wells. The model was used for simulating existing and proposed water management strategies as a tool to ensure the utmost security for drinking water. A systematic evaluation of the flow direction and magnitude between existing observation points using a newly developed three point estimation method for a large amount of scenarios was carried out. Due to the numerous observation points 32 triangles (three-points) were created which cover the entire area around the Hardwald. We demonstrated that systematically applying our developed methodology helps to identify important locations which are sensitive to changing boundary conditions and where additional protection is required without highly computational demanding transport modelling. The presented integrated approach using the flow direction

  16. Assimilating ambiguous observations to jointly estimate groundwater recharge and conductivity

    Science.gov (United States)

    Erdal, Daniel; Cirpka, Olaf A.

    2016-04-01

    In coupled modelling of catchments, the groundwater compartment can be an important water storage as well as having influence on both rivers and evapotranspirational fluxes. It is therefore important to parameterize the groundwater model as correctly as possible. Primarily important to regional groundwater flow is the spatially variable hydraulic conductivity. However, also the groundwater recharge, in a coupled system coming from the unsaturated zone but in a stand-alone groundwater model a boundary condition, is also of high importance. As with all subsurface systems, groundwater properties are difficult to observe in reality and their estimation is an ongoing topic in groundwater research and practice. Commonly, we have to rely on time series of groundwater head observations as base for any parameter estimation. Heads, however, have the drawback that they can be ambiguous and may not uniquely define the inverse problem, especially if both recharge and conductivity are seen as unknown. In the presented work we use a 2D virtual groundwater test case to investigate how the prior knowledge of recharge and conductivity influence their respective and joint estimation as spatially variable fields using head data. Using the Ensemble Kalman filter, it is shown that the joint estimation is possible if the prior knowledge is good enough. If the prior is erroneous the a-priori sampled fields cannot be corrected by the data. However, it is also shown that if the prior knowledge is directly wrong the estimated recharge field can resemble the true conductivity field, resulting in a model that meets the observations but has very poor predictive power. The study exemplifies the importance of prior knowledge in the joint estimation of parameters from ambiguous measurements.

  17. Qualitative analysis of Orzooiyeh plain groundwater resources using GIS techniques

    Directory of Open Access Journals (Sweden)

    Mohsen Pourkhosravani

    2016-09-01

    Full Text Available Background: Unsustainable development of human societies, especially in arid and semi-arid areas, is one of the most important environmental hazards that require preservation of groundwater resources, and permanent study of qualitative and quantitative changes through sampling. Accordingly, this research attempts to assess and analyze the spatial variation of quantitative and qualitative indicators of Orzooiyeh groundwater resources in the Kerman province by using the geographic information system (GIS. Methods: This study attempts to survey the spatial analysis of these indexes using GIS techniques besides the evaluation of the groundwater resources quality in the study area. For this purpose, data quality indicators and statistics such as electrical conductivity, pH, sulphate, residual total dissolved solids (TDS, sodium, calcium; magnesium and chlorine of 28 selected wells sampled by the Kerman regional water organization were used. Results: A comparison of the present research results with standard of Industrial Research of Iran and also the World Health Organization (WHO shows that, among the measured indices, the electrical conductivity and TDS in the chosen samples are higher than the national standard of Iran and of the WHO but other indices are more favourable. Conclusion: Results showed that the electrical conductivity index of 64.3% of the samples have an optimal level, 71.4% have the limit of Iran national standard and only 3.6% of them have the WHO standard. The TDS index, too, did not reach national standards in any of the samples and in 82.1% of the samples this index was on the national standard limit. As per this index, only 32.1% of the samples were in the WHO standards.

  18. Improved water resource management for a highly complex environment using three-dimensional groundwater modelling

    Science.gov (United States)

    Moeck, Christian; Affolter, Annette; Radny, Dirk; Dressmann, Horst; Auckenthaler, Adrian; Huggenberger, Peter; Schirmer, Mario

    2017-08-01

    A three-dimensional groundwater model was used to improve water resource management for a study area in north-west Switzerland, where drinking-water production is close to former landfills and industrial areas. To avoid drinking-water contamination, artificial groundwater recharge with surface water is used to create a hydraulic barrier between the contaminated sites and drinking-water extraction wells. The model was used for simulating existing and proposed water management strategies as a tool to ensure the utmost security for drinking water. A systematic evaluation of the flow direction between existing observation points using a developed three-point estimation method for a large number of scenarios was carried out. It is demonstrated that systematically applying the developed methodology helps to identify vulnerable locations which are sensitive to changing boundary conditions such as those arising from changes to artificial groundwater recharge rates. At these locations, additional investigations and protection are required. The presented integrated approach, using the groundwater flow direction between observation points, can be easily transferred to a variety of hydrological settings to systematically evaluate groundwater modelling scenarios.

  19. Estimation of groundwater resources in the upper Guadiana basin together with some observations concerning the definitions of renewable and available resources; Cuantificacion de recursos hidricos subterraneos en la cuenca alta del Guadiana. Consideraciones respecto a las definiciones de recursos renovables y disponibles

    Energy Technology Data Exchange (ETDEWEB)

    Martinez Cortina, L.; Mejias Moreno, M.; Diaz Munoz, J. A.; Morales Garcia, R.; Ruiz Hernandez, J. M.

    2011-07-01

    The European Union Water Framework Directive requires the quantification of groundwater resources according to the new hydrogeological classification into groundwater bodies (GWBs). This evaluation is to be made taking into account the established criteria deriving from the directive, which requires an estimation of the so-called available groundwater resources for each GWB. The quantification of detailed water balances for each GWB of the upper Guadiana basin has been undertaken bearing in mind different historical and current conditions. This study further examines the definitions made by the official documents concerning hydrological planning with regard to renewable and available groundwater resources, and attempts to apply them to the upper Guadiana basin. In the light of new problems arising with regard to the hydrogeological criteria applied to these definitions, a revision of the defined concepts is suggested. This paper also analyses the possibilities of future evolution of the hydrological system in the upper Guadiana basin, and provides some recommendations for groundwater exploitation with the aim of achieving the environmental recovery of the system. (Author) 19 refs.

  20. Investigation of Pb, Cd, Cu and Mg Concentrations in Groundwater Resources of Razan Plain

    OpenAIRE

    S. Sobhan Ardakani; M. Maanijou; Asadi, H.

    2015-01-01

    Introduction & Objective: Iran is located in the dry and semi dry regions, thus almost 90% of the required fresh water is exploited from groundwater resources. Due to the increasing pol-lution of water resources, the purpose of this study was evaluation of Pb, Cd, Cu and Mg concentrations in groundwater resources of Razan Plain and preparing the zoning map using GIS. Materials & Methods: Groundwater samples were collected from 20 selected stations during two seasons in 2012. The samples were ...

  1. Development of a complex groundwater model to assess the relation among groundwater resource exploitation, seawater intrusion and land subsidence

    Science.gov (United States)

    Hsi Ting, Fang; Yih Chi, Tan; Chen, Jhong Bing

    2016-04-01

    The land subsidence, which is usually irreversible, in Taiwan Pintung Plain occurred due to groundwater overexploitation. Many of the land subsidence areas in Taiwan are located in coastal area. It could not only result in homeland loss, but also vulnerability to flooding because the function of drainage system and sea wall are weakened for the lowered ground surface. Groundwater salinization and seawater intrusion could happen more easily as well. This research focuses on grasping the trend of environmental change due to the damage and impact from inappropriate development of aquaculture in the last decades. The main task is developing the artificial neural networks (ANNs) and complex numerical model for conjunctive use of surface and groundwater which is composed of a few modules such as land use, land subsidence, contamination transportation and etc. An approach based on self-organizing map (SOM) is proposed to delineate groundwater recharge zones. Several topics will be studied such as coupling of surface water and groundwater modeling, assessing the benefit of improving groundwater resources by recharge, identifying the improper usage of groundwater resources, and investigating the effect of over-pumping on land subsidence in different depth. In addition, a complete plan for managing both the flooding and water resources will be instituted by scheming non-engineering adaptation strategies for homeland planning, ex. controlling pumping behavior in area vulnerable to land subsidence and increasing groundwater recharge.

  2. Calculating and Evaluating the Groundwater Resource of Jian San Jiang Area

    Institute of Scientific and Technical Information of China (English)

    2002-01-01

    According to the method of water balance,the parameters of groundwater resouce of Jian San Jiang area have been calculated in the paper. At the same time,the quality of water supplying and water mining can be calculated. Furthermore ,the groundwater resource have been evaluated. Thus ,the paper provides the important references for managers to using groundwater reasonable.

  3. Simulation of Saline Groundwater Resources Surrounding Salt Lake in Fars Province of Iran

    Science.gov (United States)

    Khayyat Kholghi, Majid; Bastani, Mehrdad; Rakhshandeoroo, Gholamreza

    2010-05-01

    One of the most salty lakes in Iran is located in North-East of Fars province with Electrical Conductivities (EC) of up to 61420 μmhos/cm where water supply depends severely on groundwater resources. Increasing demand for freshwater and overexploitation of the aquifer has caused a drawdown in groundwater levels followed by a seawater intrusion into the coastal aquifer in the vicinity of salt lake. Because of invalid appropriate groundwater flow and solute transport parameter values of the coastal system, studying and modelling of saltwater intrusion in this region is in some way complicated. These unknown parameters are consisted of hydraulic conductivity, porosity, specific storage coefficient and longitudinal dispersivity. In this research, it is tried to facilitate study this problem by means of SEAWAT code, which is suitable for variable-density groundwater flow modelling. In the process of calibrating the simulation and estimating the required unknown parameters, an attempt at inverse modelling of a seawater intrusion system is made by using genetic algorithm method as the optimization procedure. The auto-calibration objective function is defined with the root mean square errors (RMSE) between the observed and the simulated values. The observed data are consisted of both hydraulic heads and concentrations obtained from observation wells. Firstly, the SEAWAT code has been used for forward solution part of salt water intrusion phenomena and then a program is written in MATLAB for coupling the forward and inverse processes. In the developed code, the flow and transport parameters are estimated simultaneously in steady and transient states. Using these estimated parameters in the structure of the simulation consequences more accurate results and more trustable model for next applications in management of the coastal aquifer. Key words seawater intrusion; saline groundwater resources; SEAWAT; genetic algorithm; Fars province

  4. Global modeling of withdrawal, allocation and consumptive use of surface water and groundwater resources

    Directory of Open Access Journals (Sweden)

    Y. Wada

    2013-02-01

    Full Text Available To sustain growing food demand and increasing standard of living, global water withdrawal and consumptive water use have been increasing rapidly. To analyze the human perturbation on water resources consistently over a large scale, a number of macro-scale hydrological models (MHMs have been developed over the recent decades. However, few models consider the feedback between water availability and water demand, and even fewer models explicitly incorporate water allocation from surface water and groundwater resources. Here, we integrate a global water demand model into a global water balance model, and simulate water withdrawal and consumptive water use over the period 1979–2010, considering water allocation from surface water and groundwater resources and explicitly taking into account feedbacks between supply and demand, using two re-analysis products: ERA-Interim and MERRA. We implement an irrigation water scheme, which works dynamically with daily surface and soil water balance, and include a newly available extensive reservoir data set. Simulated surface water and groundwater withdrawal show generally good agreement with available reported national and sub-national statistics. The results show a consistent increase in both surface water and groundwater use worldwide, but groundwater use has been increasing more rapidly than surface water use since the 1990s. Human impacts on terrestrial water storage (TWS signals are evident, altering the seasonal and inter-annual variability. The alteration is particularly large over the heavily regulated basins such as the Colorado and the Columbia, and over the major irrigated basins such as the Mississippi, the Indus, and the Ganges. Including human water use generally improves the correlation of simulated TWS anomalies with those of the GRACE observations.

  5. Groundwater resources of the Devils Postpile National Monument—Current conditions and future vulnerabilities

    Science.gov (United States)

    Evans, William C.; Bergfeld, Deborah

    2017-06-15

    This study presents an extensive database on groundwater conditions in and around Devils Postpile National Monument. The database contains chemical analyses of springs and the monument water-supply well, including major-ion chemistry, trace element chemistry, and the first information on a list of organic compounds known as emerging contaminants. Diurnal, seasonal, and annual variations in groundwater discharge and chemistry are evaluated from data collected at five main monitoring sites, where streams carry the aggregate flow from entire groups of springs. These springs drain the Mammoth Mountain area and, during the fall months, contribute a significant fraction of the San Joaquin River flow within the monument. The period of this study, from fall 2012 to fall 2015, includes some of the driest years on record, though the seasonal variability observed in 2013 might have been near normal. The spring-fed streams generally flowed at rates well below those observed during a sequence of wet years in the late 1990s. However, persistence of flow and reasonably stable water chemistry through the recent dry years are indicative of a sizeable groundwater system that should provide a reliable resource during similar droughts in the future. Only a few emerging contaminants were detected at trace levels below 1 microgram per liter (μg/L), suggesting that local human visitation is not degrading groundwater quality. No indication of salt from the ski area on the north side of Mammoth Mountain could be found in any of the groundwaters. Chemical data instead show that natural mineral water, such as that discharged from local soda springs, is the main source of anomalous chloride in the monument supply well and in the San Joaquin River. The results of the study are used to develop a set of recommendations for future monitoring to enable detection of deleterious impacts to groundwater quality and quantity

  6. Groundwater depletion in Central Mexico: Use of GRACE and InSAR to support water resources management

    Science.gov (United States)

    Castellazzi, Pascal; Martel, Richard; Rivera, Alfonso; Huang, Jianliang; Pavlic, Goran; Calderhead, Angus I.; Chaussard, Estelle; Garfias, Jaime; Salas, Javier

    2016-08-01

    Groundwater deficits occur in several areas of Central Mexico, where water resource assessment is limited by the availability and reliability of field data. In this context, GRACE and InSAR are used to remotely assess groundwater storage loss in one of Mexico's most important watersheds in terms of size and economic activity: the Lerma-Santiago-Pacifico (LSP). In situ data and Land Surface Models are used to subtract soil moisture and surface water storage changes from the total water storage change measured by GRACE satellites. As a result, groundwater mass change time-series are obtained for a 12 years period. ALOS-PALSAR images acquired from 2007 to 2011 were processed using the SBAS-InSAR algorithm to reveal areas subject to ground motion related to groundwater over-exploitation. In the perspective of providing guidance for groundwater management, GRACE and InSAR observations are compared with official water budgets and field observations. InSAR-derived subsidence mapping generally agrees well with official water budgets, and shows that deficits occur mainly in cities and irrigated agricultural areas. GRACE does not entirely detect the significant groundwater losses largely reported by official water budgets, literature and InSAR observations. The difference is interpreted as returns of wastewater to the groundwater flow systems, which limits the watershed scale groundwater depletion but suggests major impacts on groundwater quality. This phenomenon is enhanced by ground fracturing as noticed in the field. Studying the fate of the extracted groundwater is essential when comparing GRACE data with higher resolution observations, and particularly in the perspective of further InSAR/GRACE combination in hydrogeology.

  7. Groundwater Resources and Land Subsidence investigations in the Toluca Valley, Mexico

    Science.gov (United States)

    Calderhead, A. I.; Martel, R.; Rivera, A.; Garfias, J.; Therrien, R.

    2007-05-01

    The sustained growth in population in the Toluca Valley and neighboring Mexico City has primarily depended on the continuous development of both local and regional water resources for industrial, agricultural and domestic uses. The Toluca Valley Basin, covering an area of approximately 2000 Km2, is the focus of this study. Currently, there is a significant net loss of water within the basin primarily due to groundwater pumping, and the loss is increasing with time. These stresses on the aquifer have caused significant changes on the water flow patterns, a reversal in the direction of hydraulic gradients, the disappearance of artesian springs and wetlands and noticeable land subsidence within the basin. Neighboring Mexico City's land subsidence problems have been well documented, however, no comprehensive studies exist for the Toluca Basin. This study is divided into two parts: 1) investigation of groundwater depletion in the Toluca Valley; and 2) assessment of land subsidence in the Toluca Valley. We examine various changes in regional flow patterns, and groundwater levels decline throughout the valley and 3D numerical flow simulations are run to predict the ever decreasing level of the piezometric surface. Currently there is a net loss (recharge - extraction) of 142 Mm3 per year of groundwater within the Toluca Basin aquifers. We have documented a decrease in groundwater levels with a rate of up to 1.4 m/year between 1970 and 2006 in the central part of the valley. At the current rate of consumption, groundwater resources will not be sustainable for the population of the valley. Directly related to the drawdown in groundwater levels is the occurrence of land subsidence throughout the valley. Neighboring Mexico City, where total subsidence of up to 9 meters has been observed, has a similar geology as the one in the Toluca valley. We have documented several sites in the Toluca Valley where land subsidence is occurring. Ongoing work includes the mapping of regional

  8. Groundwater Resources Pollution Risk: Application of the Holman Method

    Directory of Open Access Journals (Sweden)

    M. D. Maio

    2009-01-01

    Full Text Available Problem statement: The aim of this study is to make an attempt to assess, through the application of the Holman Method, the effects that a careless management of human induced activities could have on aquifers and in particular on tapping wells used for human supply. Approach: The study had been applied to two different territories, as far as both the geomorphological and human induced aspects are concerned: the city of Aosta, the capital city of the Autonomous Aosta Valley region and three municipalities located in the centre of the Veneto region. Results: Thanks to the first results that had been obtained from the application of this method and other ones, it is hoped that a strategic territorial management approach will be adopted in the future so that the Groundwater Resources (GWR can coexist with the economic and urban developments. Conclusion: All the analysis had been implemented utilizing a Geographical Information System (GIS.

  9. Earth observation for regional scale environmental and natural resources management

    Science.gov (United States)

    Bernknopf, R.; Brookshire, D.; Faulkner, S.; Chivoiu, B.; Bridge, B.; Broadbent, C.

    2013-12-01

    Earth observations (EO) provide critical information to natural resource assessment. Three examples are presented: conserving potable groundwater in intense agricultural regions, maximizing ecosystem service benefits at regional scales from afforestation investment and management, and enabling integrated natural and behavioral sciences for resource management and policy analysis. In each of these cases EO of different resolutions are used in different ways to help in the classification, characterization, and availability of natural resources and ecosystem services. To inform decisions, each example includes a spatiotemporal economic model to optimize the net societal benefits of resource development and exploitation. 1) EO is used for monitoring land use in intensively cultivated agricultural regions. Archival imagery is coupled to a hydrogeological process model to evaluate the tradeoff between agrochemical use and retention of potable groundwater. EO is used to couple individual producers and regional resource managers using information from markets and natural systems to aid in the objective of maximizing agricultural production and maintaining groundwater quality. The contribution of EO is input to a nitrate loading and transport model to estimate the cumulative impact on groundwater at specified distances from specific sites (wells) for 35 Iowa counties and two aquifers. 2) Land use/land cover (LULC) derived from EO is used to compare biological carbon sequestration alternatives and their provisioning of ecosystem services. EO is used to target land attributes that are more or less desirable for enhancing ecosystem services in two parishes in Louisiana. Ecological production functions are coupled with value data to maximize the expected return on investment in carbon sequestration and other ancillary ecosystem services while minimizing the risk. 3) Environmental and natural resources management decisions employ probabilistic estimates of yet-to-find or yet

  10. Forecasting and Managing Groundwater Resources Using InSAR

    Science.gov (United States)

    Zebker, H. A.; Knight, R. J.; Chen, J.

    2014-12-01

    Groundwater management is highly dependent on the type and quality of field data available describing a given aquifer system. Our increasing reliance on groundwater, especially as traditional surface supplies continue to be overexploited due to rising population and standard of living, requires that we better understand the state of our subsurface supplies and how to best manage them. The dense spatial and temporal variability of subsidence provided by time series InSAR allows us to constrain the extent of an aquifer, its storage coefficient, estimates of hydraulic head, and hydraulic conductivity. We present examples of these parameters associated with groundwater systems in the San Luis Valley, CO, and the Central Valley area of California, as observed by several spaceborne radar systems and validated by comparison with field data. Groundwater is one component of a water system, which includes surface supplies and all of the various sources and end uses of water in a particular area. Confined aquifers remain the most difficult components of a full water system to characterize and properly manage, as they lie deep underground and are hidden from direct observation. We show that observing subtle deformations of the surface elevations on the order of mm to cm yield important constraints on the underlying aquifer and its hydraulic properties, because variations in the surface height expresses changes in water pressure below. The fundamental relation between pressure and stress resulting in changes in hydraulic head yields a simple linear relationship between deformation Δb, hydraulic head Δh, and skeletal storage coefficient: Sk = Δb / Δh, so that measuring deformation everywhere above an aquifer over time yields change in head. Using InSAR-observed temporal response of the head (deformation) to changes in forcing by water sources and sinks, and applying the one dimensional diffusion equation resulting from Darcy's Law and the continuity relation allows us to

  11. Preconditioning an ensemble Kalman filter for groundwater flow using environmental-tracer observations

    Science.gov (United States)

    Erdal, Daniel; Cirpka, Olaf A.

    2017-02-01

    Groundwater resources management requires operational, regional-scale groundwater models accounting for dominant spatial variability of aquifer properties and spatiotemporal variability of groundwater recharge. We test the Ensemble Kalman filter (EnKF) to estimate transient hydraulic heads and groundwater recharge, as well as the hydraulic conductivity and specific-yield distributions of a virtual phreatic aquifer. To speed up computation time, we use a coarsened spatial grid in the filter simulations, and reconstruct head measurements at observation points by a local model in the vicinity of the piezometer as part of the observation operator. We show that the EnKF can adequately estimate both the mean and spatial patterns of hydraulic conductivity when assimilating daily values of hydraulic heads from a highly variable initial sample. The filter can also estimate temporally variable recharge to a satisfactory level, as long as the ensemble size is large enough. Constraining the parameters on concentrations of groundwater-age tracers (here: tritium) and transient hydraulic-head observations cannot reasonably be done by the EnKF because the concentrations depend on the recharge history over longer times while the head observations have much shorter temporal support. We thus use a different method, the Kalman Ensemble Generator (KEG), to precondition the initial ensemble of the EnKF on the groundwater-age tracer data and time-averaged hydraulic-head values. The preconditioned initial ensemble exhibits a smaller spread as well as improved means and spatial patterns. The preconditioning improves the EnKF particularly for smaller ensemble sizes, allowing operational data assimilation with reduced computational effort. In a validation scenario of delineating groundwater protection zones, the preconditioned filter performs clearly better than the filter using the original initial ensemble.

  12. Global Modeling of Withdrawal, Allocation and Consumptive Use of Surface Water and Groundwater Resources

    Science.gov (United States)

    Wada, Y.; Wisser, D.; Bierkens, M. F.

    2014-12-01

    To sustain growing food demand and increasing standard of living, global water withdrawal and consumptive water use have been increasing rapidly. To analyze the human perturbation on water resources consistently over large scales, a number of macro-scale hydrological models (MHMs) have been developed in recent decades. However, few models consider the interaction between terrestrial water fluxes, and human activities and associated water use, and even fewer models distinguish water use from surface water and groundwater resources. Here, we couple a global water demand model with a global hydrological model and dynamically simulate daily water withdrawal and consumptive water use over the period 1979-2010, using two re-analysis products: ERA-Interim and MERRA. We explicitly take into account the mutual feedback between supply and demand, and implement a newly developed water allocation scheme to distinguish surface water and groundwater use. Moreover, we include a new irrigation scheme, which works dynamically with a daily surface and soil water balance, and incorporate the newly available extensive global reservoir data set (GRanD). Simulated surface water and groundwater withdrawals generally show good agreement with reported national and sub-national statistics. The results show a consistent increase in both surface water and groundwater use worldwide, with a more rapid increase in groundwater use since the 1990s. Human impacts on terrestrial water storage (TWS) signals are evident, altering the seasonal and inter-annual variability. This alteration is particularly large over heavily regulated basins such as the Colorado and the Columbia, and over the major irrigated basins such as the Mississippi, the Indus, and the Ganges. Including human water use and associated reservoir operations generally improves the correlation of simulated TWS anomalies with those of the GRACE observations.

  13. Hydrogeologic and geochemical characterization of groundwater resources in Rush Valley, Tooele County, Utah

    Science.gov (United States)

    Gardner, Philip M.; Kirby, Stefan

    2011-01-01

    The water resources of Rush Valley were assessed during 2008-2010 with an emphasis on refining the understanding of the groundwater-flow system and updating the groundwater budget. Surface-water resources within Rush Valley are limited and are generally used for agriculture. Groundwater is the principal water source for most other uses including supplementing irrigation. Most groundwater withdrawal in Rush Valley is from the unconsolidated basin-fill aquifer where conditions are generally unconfined near the mountain front and confined at lower altitudes near the valley center. Productive aquifers also occur in fractured bedrock along the valley margins and beneath the basin-fill deposits in some areas.

  14. Groundwater Resources of Ribeira Paul Basin, Island of Santo Antao, Cape Verde, West Africa

    Science.gov (United States)

    Heilweil, Victor M.; Gingerich, Stephen B.; Verstraeten, Ingrid M.

    2010-01-01

    Groundwater resources in Cape Verde provide water for agriculture, industry, and human consumption. These resources are limited and susceptible to contamination. Additional groundwater resources are needed for continued agricultural development, particularly during times of drought, but increased use and (or) climatic change may have adverse effects on the quantity and quality of freshwater available. In volcanic island aquifers such as those of Cape Verde, a lens of fresh groundwater typically ?floats? upon a layer of brackish water at the freshwater/saltwater boundary, and increased pumping may cause salt water intrusion or other contamination. A recent U.S. Geological Survey study assessed baseline groundwater conditions in watersheds on three islands of Cape Verde to provide the scientific basis for sustainably developing water resources and minimizing future groundwater depletion and contamination.

  15. Groundwater Resources of Ribeira Faja Basin, Island of Sao Nicolau, Cape Verde, West Africa

    Science.gov (United States)

    Heilweil, Victor M.; Gingerich, Stephen B.; Plummer, L. Niel; Verstraeten, Ingrid M.

    2010-01-01

    Groundwater resources in Cape Verde provide water for agriculture, industry, and human consumption. These resources are limited and susceptible to contamination. Additional groundwater resources are needed for continued agricultural development, particularly during times of drought, but increased use and (or) climatic change may have adverse effects on the quantity and quality of freshwater available. In volcanic island aquifers such as those of Cape Verde, a lens of fresh groundwater typically ?floats? upon a layer of brackish water at the freshwater/saltwater boundary, and increased pumping may cause salt water intrusion or other contamination. A recent U.S. Geological Survey study assessed baseline groundwater conditions in watersheds on three islands of Cape Verde to provide the scientific basis for sustainably developing water resources and minimizing future groundwater depletion and contamination.

  16. Groundwater Resources of Mosteiros Basin, Island of Fogo, Cape Verde, West Africa

    Science.gov (United States)

    Heilweil, Victor M.; Gingerich, Stephen B.; Plummer, L. Niel; Verstraeten, Ingrid M.

    2010-01-01

    Groundwater resources in Cape Verde provide water for agriculture, industry, and human consumption. These resources are limited and susceptible to contamination. Additional groundwater resources are needed for continued agricultural development, particularly during times of drought, but increased use and (or) climatic change may have adverse effects on the quantity and quality of freshwater available. In volcanic island aquifers such as those of Cape Verde, a lens of fresh groundwater typically ?floats? upon a layer of brackish water at the freshwater/saltwater boundary, and increased pumping may cause salt water intrusion or other contamination. A recent U.S. Geological Survey study assessed baseline groundwater conditions in watersheds on three islands of Cape Verde to provide the scientific basis for sustainably developing water resources and minimizing future groundwater depletion and contamination.

  17. Economic, social and resource management factors influencing groundwater trade: Evidence from Victoria, Australia

    Science.gov (United States)

    Gill, Bruce; Webb, John; Stott, Kerry; Cheng, Xiang; Wilkinson, Roger; Cossens, Brendan

    2017-07-01

    In Victoria, Australia, most groundwater resources are now fully allocated and opportunities for new groundwater development can only occur through trading of license entitlements. Groundwater usage has rarely exceeded 50% of the available licensed volume, even in the 2008/9 drought year, and 50 to 70% of individual license holders use less than 5% of their allocation each year. However, little groundwater trading is occurring at present. Interviews were conducted with groundwater license holders and water brokers to investigate why the Victorian groundwater trade market is underdeveloped. Responses show there is a complex mix of social, economic, institutional and technical reasons. Barriers to trade are influenced by the circumstances of each groundwater user, administrative process and resource management rules. Water brokers deal with few trades at low margins and noted unrealistic selling prices and administrative difficulties. Irrigators who have successfully traded identify that there are few participants in trading, technical appraisals are expensive and administrative requirements and fees are burdensome, especially when compared to surface water trading. Opportunities to facilitate trade include groundwater management plan refinement and improved information provision. Simplifying transaction processes and costs, demonstrating good resource stewardship and preventing third party impacts from trade could address some concerns raised by market participants. There are, however, numerous individual circumstances that inhibit groundwater trading, so it is unlikely that policy and process changes alone could increase usage rates without greater demand for groundwater or more favourable farming economic circumstances.

  18. Long-term detection and hydrochemistry of groundwater resources in Egypt: Case study of Siwa Oasis

    Directory of Open Access Journals (Sweden)

    Anwar A. Aly

    2016-01-01

    Full Text Available Water, it is said, will be the oil of the twenty-first century. Successful water management will be the key to future economic growth and social wealth in both developed and developing countries. Due to the continuous agricultural expansion, urban development, and increased demands on limited water supplies, Egypt is compelled to look for unconventional water resources. One of the most important sources is groundwater in the western desert of Egypt. More water abstraction is currently taking place raising the dangers of overexploitation and deterioration of water quality in Siwa Oasis located in Egypt western desert. The main objectives of this study are to monitor the quality of the Siwa Oasis groundwater over ten years. The present paper presents the results of this investigation and the future outlook for the situation of the limited water resources of the oasis. The data showed spatial differences between water qualities obtained from different locations within the Oasis. It was also observed that there are temporal changes and that water quality is deteriorating in alarming rate over time. Most studied water samples were considered unsuitable for irrigation due to salinity hazards. The reason that may contribute to speeding up groundwater quality deterioration is the unsafe ground water mining on the deep sandstone aquifers which causes the decreases of the fresh water vertical movement from the deep sandstone aquifer to the surface limestone aquifer.

  19. Global Depletion of Groundwater Resources: Past and Future Analyses

    Science.gov (United States)

    Bierkens, M. F.; de Graaf, I. E. M.; Van Beek, L. P.; Wada, Y.

    2014-12-01

    Globally, about 17% of the crops are irrigated, yet irrigation accounts for 40% of the global food production. As more than 40% of irrigation water comes from groundwater, groundwater abstraction rates are large and exceed natural recharge rates in many regions of the world, thus leading to groundwater depletion. In this paper we provide an overview of recent research on global groundwater depletion. We start with presenting various estimates of global groundwater depletion, both from flux based as well as volume based methods. We also present estimates of the contribution of non-renewable groundwater to irrigation water consumption and how this contribution developed during the last 50 years. Next, using a flux based method, we provide projections of groundwater depletion for the coming century under various socio-economic and climate scenarios. As groundwater depletion contributes to sea-level rise, we also provide estimates of this contribution from the past as well as for future scenarios. Finally, we show recent results of groundwater level changes and change in river flow as a result of global groundwater abstractions as obtained from a global groundwater flow model.

  20. Aquifers of Arkansas: protection, management, and hydrologic and geochemical characteristics of groundwater resources in Arkansas

    Science.gov (United States)

    Kresse, Timothy M.; Hays, Phillip D.; Merriman, Katherine R.; Gillip, Jonathan A.; Fugitt, D. Todd; Spellman, Jane L.; Nottmeier, Anna M.; Westerman, Drew A.; Blackstock, Joshua M.; Battreal, James L.

    2014-01-01

    Sixteen aquifers in Arkansas that currently serve or have served as sources of water supply are described with respect to existing groundwater protection and management programs, geology, hydrologic characteristics, water use, water levels, deductive analysis, projections of hydrologic conditions, and water quality. State and Federal protection and management programs are described according to regulatory oversight, management strategies, and ambient groundwater-monitoring programs that currently (2013) are in place for assessing and protecting groundwater resources throughout the State.

  1. Satellite Observations of Groundwater Storage Variations and Their Application for Water Security Monitoring

    Science.gov (United States)

    Rodell, M.; Famiglietti, J. S.; Li, B.; Kumar, S.; Reager, J. T., II

    2015-12-01

    Fresh water demand is steadily increasing around the world due to population growth, economic development, and people's desire for a "western" lifestyle and diet. Where surface water availability is not sufficient or consistent, groundwater is often the resource of choice for agriculture, industry, and municipal and domestic uses. However, unlike lake levels, aquifer levels are unseen and are not easily measured. This can create the illusion of an infinite water source and impede efforts to monitor and conserve groundwater. Moreover, even where depth-to-water measurements do exist, they often are not digitized, centralized, and accessible. The GRACE satellites are a partial solution to this problem, enabling space-based estimates of groundwater variability at regional scales that are not limited by political boundaries. Here we discuss emerging trends in groundwater storage around the world based on GRACE observations and how they can be combined with other information in order attribute these apparent trends and support sub-regional scale analyses of changing groundwater availability.

  2. Depleting groundwater resources mitigating surface freshwater scarcity - a trend in the recent past

    Science.gov (United States)

    Wada, Y.; Van Beek, L. P.; Bierkens, M. F.

    2011-12-01

    During the past decades, human water use more than doubled, yet available surface freshwater resources are finite. As a result, water scarcity has become prevalent in many (semi-)arid regions of the world (e.g., India, Pakistan, North East China, the MENA region). In such regions, the demand often exceeds the available surface freshwater resources primarily due to heavy irrigation which requires large volumes of water in a certain time of the year, when groundwater is additionally used to supplement the deficiency. Excessive groundwater pumping, however, often leads to overexploitation, i.e. groundwater abstraction exceeding groundwater recharge. Here, we quantified globally the impact of depleting groundwater resources on mitigating surface freshwater scarcity and the trend between 1960 and 2000 at a spatial resolution of 0.5 degree. We downscaled available country statistics of groundwater abstraction to 0.5 degree, while we simulated groundwater recharge with the global hydrological model PCR-GLOBWB at the same spatial resolution considering not only natural groundwater recharge but also artificial recharge, i.e. return flow from irrigation. Water scarcity was estimated by confronting computed water demand for livestock, irrigation, industry and households with simulated surface freshwater availability (PCR-GLOBWB) at 0.5 degree. We thus performed a simulation run with/without groundwater pumping to assess the impact on alleviating surface freshwater scarcity. The results indicated that in many of (semi-)arid regions (e.g., North Wet India, North East Pakistan, North East China, West and Central USA, Central Mexico, North Iran, Central Saudi Arabia) large amounts of groundwater abstraction significantly mitigates the intensity of surface freshwater scarcity, while depleting the resources. Our estimate of global groundwater depletion reached close to 280 km3/yr. In most of the MENA region, the intensity of surface freshwater scarcity was eased by 30% up to 50% as

  3. Ground-Water Recharge in Humid Areas of the United States--A Summary of Ground-Water Resources Program Studies, 2003-2006

    Science.gov (United States)

    Delin, Geoffrey N.; Risser, Dennis W.

    2007-01-01

    Increased demands on water resources by a growing population and recent droughts have raised awareness about the adequacy of ground-water resources in humid areas of the United States. The spatial and temporal variability of ground-water recharge are key factors that need to be quantified to determine the sustainability of ground-water resources. Ground-water recharge is defined herein as the entry into the saturated zone of water made available at the water-table surface, together with the associated flow away from the water table within the saturated zone (Freeze and Cherry, 1979). In response to the need for better estimates of ground-water recharge, the Ground-Water Resources Program (GWRP) of the U.S. Geological Survey (USGS) began an initiative in 2003 to estimate ground-water recharge rates in the relatively humid areas of the United States.

  4. The Evaluation of Groundwater Resources Value of Beijing Based on Emergy Theory

    Directory of Open Access Journals (Sweden)

    Ling Wang

    2015-01-01

    for industry (GWCRI 4.52%, groundwater contribution rate for agriculture (GWCRA 3.24%, and groundwater contribution rate for residential life (GWCRL 0.71%. The conclusions will provide important basis for the government’s scientific decision to improve the level of comprehensive management of water resource.

  5. Impacts of afforestation on groundwater resources and quality

    Science.gov (United States)

    Allen, Alistair; Chapman, Deborah

    2001-07-01

    Plans to double the proportion of land under forest cover in Ireland by the year 2035 have been initiated. The plan, primarily financially driven, ignores potential environmental impacts of forestry, particularly impacts on groundwater resources and quality. Since groundwater supplies almost 25% of Ireland's total potable water, these impacts are important. Field investigations indicate that afforestation leads to a reduction in runoff by as much as 20%, mainly due to interception of rainfall by forest canopies. Clearfelling has the opposite impact. Implications are that uncoordinated forestry practices can potentially exacerbate flooding. Groundwater recharge is affected by forestry, largely due to greater uptake of soil water by trees and to increased water-holding capacity of forest soils, arising from higher organic contents. Recharge rates under forests can be reduced to one tenth that under grass or heathland. Groundwater quality may be affected by enhanced acidification and nitrification under forests, due partly to scavenging of atmospheric pollutants by forest canopies, and partly to greater deposition of highly acid leaf litter. The slower recharge rates of groundwater under forests lead to significant delays in manifestation of deterioration in groundwater quality. Résumé. Des plans sont à l'étude pour doubler la proportion du couvert forestier en Irlande d'ici à 2035. Le plan, primitivement déterminé sur une base financière, ignore les impacts environnementaux potentiels de la foresterie, et particulièrement les impacts sur les ressources en eau souterraine et leur qualité. Du fait que les eaux souterraines satisfont presque 25% du total de l'eau potable de l'Irlande, ces impacts sont importants. Les études de terrain montrent que le reboisement conduit à une réduction du ruissellement d'au moins 20%, principalement à cause d'une interception de la pluie par le couvert forestier. Les coupes ont un impact contraire. Les implications sont

  6. Water resources management strategies and its implications on hydrodynamic and hydrochemical changes of costal groundwater: Case of Grombalia shallow aquifer, NE Tunisia

    Science.gov (United States)

    Lachaal, Fethi; Chekirbane, Anis; Chargui, Sameh; Sellami, Haykel; Tsujimura, Maki; Hezzi, Hmida; Faycel, Jelassi; Mlayah, Ammar

    2016-12-01

    Information on groundwater quantity as well as quality is required by water managers and decision-makers for defining a sustainable management strategy. This requires a comprehensive assessment of the surface water and groundwater resources. This paper provides an assessment of water resources management strategy in the Grombalia region (Northeast Tunisia) and its impact on quantity and quality evolution of groundwater resources based on an approach that combines (i) hydro-climatic data, (ii) field monitoring, (iii) historic piezometric records, and (iv) geochemical and stable isotopes (δ18O and δ2H) analyses. We apply this approach to identify the origin of the various water resources and outline how the actual water management impact the quantity and quality of the groundwater in the region. As consequence of poor water resources management, the shallow groundwater levels have been disrupted: a groundwater rise is observed in the centre and a piezometric drawdown is observed in the upstream regions. Groundwater quality degradation was registered especially in the centre and downstream zones.

  7. A Quantitative Groundwater Resource Management under Uncertainty Using a Retrospective Optimization Framework

    Directory of Open Access Journals (Sweden)

    Gislar E. Kifanyi

    2016-12-01

    Full Text Available Water resources are a major concern for any socio-economic development. As the quality of many surface fresh water sources increasingly deteriorate, more pressure is being imparted into groundwater aquifers. Since groundwater and the aquifers that host it are inherently vulnerable to anthropogenic impacts, there is a need for sustainable pumping strategies. However, groundwater resource management is challenging due to the heterogeneous nature of aquifer systems. Aquifer hydrogeology is highly uncertain, and thus it is imperative that this uncertainty is accounted for when managing groundwater resource pumping. This, therefore, underscores the need for an efficient optimization tool which can sustainably manage the resource under uncertainty conditions. In this paper, we apply a procedure which is new within the context of groundwater resource management—the Retrospective Optimization Approximation (ROA method. This method is capable of designing sustainable groundwater pumping strategies for aquifers which are characterized by uncertainty arising due to scarcity of input data. ROA framework solves and evaluates a sequence of optimization sub-problems in an increasing number of realizations. We used k-means clustering sampling technique for the realizations selection. The methodology is demonstrated through application to an hypothetical example. The optimization problem was solved and analyzed using “Active Set” algorithm implemented under MATLAB environment. The results indicate that the ROA sampling based method is a promising approach for optimizing groundwater pumping rates under conditions of hydrogeological uncertainty.

  8. Risk Analysis on Groundwater Resources Carrying Capacity Based on Blind Number Theory

    Institute of Scientific and Technical Information of China (English)

    ZHANG Ji; YU Sujun

    2007-01-01

    Blind numbers of evaluation indices about groundwater resources carrying capacity are defined from the concomitancy of randomness, fuzziness, grey property and unascertainment of groundwater system.Based on fuzzy theory, a comprehensive evaluation model on groundwaterresources carrying capacity is constructed with blind information. Then arisk assessment model of surcharge about groundwater resources carryingcapacity is established on blind reliability theory. The probable value"*"'matrix of fuzzy membership degree about carrying capacity corresponding to each judgment level can be obtained with the aid of blind algorithm as well as the subjective reliability "×" matrix. And then a graph of"groundwater carrying capacity v.s. accumulative reliability" can be gained.Based on the graph, fuzzy membership degree of groundwater resourcescarrying capacity to each judgment level under different risk probabilitycan be got. Thus, a comparatively reasonable judgment to groundwaterresources carrying capacity might be obtained, with comprehensive analysis to the state of society, economy technology and ecology.

  9. Ground-water resources of Catron County, New Mexico

    Science.gov (United States)

    Basabilvazo, G.T.

    1997-01-01

    This report describes the occurrence, availability, and quality of ground-water and related surface-water resources in Catron County, the largest county in New Mexico. The county is located in the Lower Colorado River Basin and the Rio Grande Basin, and the Continental Divide is the boundary between the two river basins. Increases in water used for mining activities (coal, mineral, and geothermal), irrigated agriculture, reservoir construction, or domestic purposes could affect the quantity or quality of ground- water and surface-water resources in the county. Parts of seven major drainage basins are within the two regional river basins in the county--Carrizo Wash, North Plains, Rio Salado, San Agustin, Alamosa Creek, Gila, and San Francisco Basins. The San Francisco, Gila, and Tularosa Rivers typically flow perennially. During periods of low flow, most streamflow is derived from baseflow. The stream channels of the Rio Salado and Carrizo Wash Basins are commonly perennial in their upper reaches and ephemeral in their lower reaches. Largo Creek in the Carrizo Wash Basin is perennial downstream from Quemado Lake and ephemeral in the lower reaches. Aquifers in Catron County include Quaternary alluvium and bolson fill; Quaternary to Tertiary Gila Conglomerate; Tertiary Bearwallow Mountain Andesite, Datil Group, and Baca Formation; Cretaceous Mesaverde Group, Crevasse Canyon Formation, Gallup Sandstone, Mancos Shale, and Dakota Sandstone; Triassic Chinle Formation; and undifferentiated rocks of Permian age. Water in the aquifers in the county generally is unconfined; however, confined conditions may exist where the aquifers are overlain by other units of lower permeability. Yields of ground water from the Quaternary alluvium in the county range from 1 to 375 gallons per minute. Yields of ground water from the alluvium in the Carrizo Wash Basin are as much as 250 gallons per minute for short time periods. North of the Plains of San Agustin, ground-water yields from the

  10. Effects of climate change on groundwater: observed and forecasted trends on Italian systems

    Science.gov (United States)

    Doveri, Marco; Menichini, Matia; Provenzale, Antonello; Scozzari, Andrea

    2017-04-01

    Groundwater represents the main source of water supply at global level. In Italy, as well as in most European countries, water needs are mainly covered by groundwater exploitation. The reliance on this resource is continuously growing, given the key role that groundwater plays for mitigating the climate change/variability and for addressing the significant increase in the global water demand. Despite this, and unlike surface waters, groundwater bodies have not been widely studied, and there is a general paucity of quantitative information, especially in relation to climate change. Although groundwater systems are more resilient to climate change than surface waters, they are affected both directly and indirectly. The estimation of the entity of these effects is mandatory for a reliable management of this crucial resource. The analysis of hydro-meteorological data over a few decades highlights that also the Italian territory is experiencing a change of the climate regime. Besides the increase of mean annual temperature, observed in particular since the early 1980s, longer and more frequent drought periods have been registered, as well as an increase of extreme events characterized by heavy rainfall. It is also noticeable a decrease in total rainfall, that is much more evident in the period from January to June. In addition to the reduced yearly inputs from precipitation, such trends determine also a lower snow accumulation and earlier snow melt in mountain areas, a general increase of evapotranspiration rates and an increased runoff fraction of the effective rainfall amount. As flood hydrographs of several major Italian rivers (e.g., Po, Brenta and Arno rivers) confirm, evident effects concern surface water resources. The main observed phenomena consist in the decline of mean annual discharge, the increase of extreme events with high discharge concentrated in short periods, and longer and earlier periods of low base flow. Impacts on groundwater recharge are not well

  11. Ground-water data for the Riley and Andrews Resource Areas, southeastern Oregon

    Science.gov (United States)

    Townley, Paul J.; Soja, Constance M.; Sidle, W.C.

    1980-01-01

    Appraisals of the resources of selected management areas in eastern Oregon are being made by the U.S. Bureau of Land Mangement. To provide needed hydrologic information, the Bureau of Land Management requested the U.S. Geological Survey to inventory ground-water data for the Riley and Andrews Resource Areas. The inventory included field location of selected wells and springs; measurement of ground-water levels, temperatures, specific conductance, and pH; and the collection of ground-water samples from selected sources to determine dissolved chemical constituents.

  12. Impact of climate change on irrigation requirements in terms of groundwater resources

    OpenAIRE

    Zhou, Yu; Zwahlen, François; Wang, Yanxin; Li, Yilian

    2013-01-01

    Climate change affects not only water resources but also water demand for irrigation. A large proportion of the world’s agriculture depends on groundwater, especially in arid and semi-arid regions. In several regions, aquifer resources face depletion. Groundwater recharge has been viewed as a by-product of irrigation return flow, and with climate change, aquifer storage of such flow will be vital. A general review, for a broad-based audience, is given of work on global warming and groundwater...

  13. Integrated assessment of groundwater resources in the Ouémé basin, Benin, West Africa

    Science.gov (United States)

    Barthel, R.; Sonneveld, B. G. J. S.; Götzinger, J.; Keyzer, M. A.; Pande, S.; Printz, A.; Gaiser, T.

    An integrated assessment of groundwater resources in Benin, West Africa was performed within the framework of the EC-funded research project RIVERTWIN ( www.rivertwin.org). The assessment included a spatial analysis of groundwater relevant parameters taken from more than 4000 wells stored in a countrywide water database (BDI - Banque des Données Intégrée) and an estimation of the spatial and temporal distribution of groundwater recharge using a modified version of the hydrological model HBV. Additionally, a socio-economic assessment of the impacts of groundwater availability and accessibility on national health issues as well as an assessment of groundwater development costs was carried out. The analysis revealed particularly unfavourable conditions for groundwater use in the northern part of the country where groundwater recharge during the wet season does not lead to the formation of persistent groundwater storage in its shallow, unconfined aquifers. Poor storage capacity and hydraulic properties of the deeper fractured aquifers additionally limit the capacity of individual wells to capture groundwater recharge. Including climate change scenarios forecasting less precipitation (generated from global climate models (GCM) based on IPCC scenarios) indicates that the situation in water scarce regions will worsen, as recharge volumes lessen and occur over a shorter time period. Drilling more wells may be a limited option to capture larger portions of the recharge, since the capture zone and therefore the regional influence of existing wells is rather small. In the south, deeper confined aquifers guarantee better and more reliable yields, yet the lack of long-term monitoring and groundwater age data does not allow an appraisal of the limits of the sustainable use of these aquifers. Finally, it has been shown that access to suitable aquifers and diarrhea prevalence are spatially correlated. Access to groundwater is thereby not only a function of aquifer suitability

  14. A Holistic Assessment of the Sustainability of Groundwater Resources in the North China Plain

    Science.gov (United States)

    Cao, G.; Zheng, C.; Liu, J.; Li, W.

    2010-12-01

    precipitation and an increase in groundwater pumping are the primary causes for groundwater depletion in the NCP. The numerical model makes it possible to integrate all the available data to provide a holistic approach to evaluate the sustainability of groundwater resources in the NCP.

  15. Groundwater.

    Science.gov (United States)

    Braids, Olin C.; Gillies, Nola P.

    1978-01-01

    Presents a literature review of groundwater quality covering publications of 1977. This review includes: (1) sources of groundwater contamination; and (2) management of groundwater. A list of 59 references is also presented. (HM)

  16. Statistical assessment of groundwater resources in Washim district (India).

    Science.gov (United States)

    Rajankar, P N; Tambekar, D H; Ramteke, D S; Wate, S R

    2011-01-01

    Groundwater quality of Washim district of Maharashtra (India) was assessed using quality parameters and water quality index (WQI). In this study, the WQI was analyzed by using pH, turbidity, temperature, nitrates, total phosphates, dissolved oxygen, biochemical oxygen demand, total solids, total coliforms and faecal coliforms, respectively for residential and commercial uses. All the parameters were analyzed both in pre-monsoon and post-monsoon seasons to assess the groundwater quality and seasonal variations. The parameters like turbidity, solids and coliforms showed the seasonal variations. The WQI varied from 72 to 88 in pre-monsoon season and 64 to 88 in post-monsoon season. The results indicate that all groundwater samples in the study area have good water quality in pre-monsoon season but in post-monsoon season 9 percent samples indicated the change in water quality from good to medium, which reveals seasonal variation and groundwater quality deterioration.

  17. Using airborne geophysical surveys to improve groundwater resource management models

    Science.gov (United States)

    Abraham, Jared D.; Cannia, James C.; Peterson, Steven M.; Smith, Bruce D.; Minsley, Burke J.; Bedrosian, Paul A.

    2010-01-01

    Increasingly, groundwater management requires more accurate hydrogeologic frameworks for groundwater models. These complex issues have created the demand for innovative approaches to data collection. In complicated terrains, groundwater modelers benefit from continuous high‐resolution geologic maps and their related hydrogeologic‐parameter estimates. The USGS and its partners have collaborated to use airborne geophysical surveys for near‐continuous coverage of areas of the North Platte River valley in western Nebraska. The survey objectives were to map the aquifers and bedrock topography of the area to help improve the understanding of groundwater‐surface‐water relationships, leading to improved water management decisions. Frequency‐domain heliborne electromagnetic surveys were completed, using a unique survey design to collect resistivity data that can be related to lithologic information to refine groundwater model inputs. To render the geophysical data useful to multidimensional groundwater models, numerical inversion is necessary to convert the measured data into a depth‐dependent subsurface resistivity model. This inverted model, in conjunction with sensitivity analysis, geological ground truth (boreholes and surface geology maps), and geological interpretation, is used to characterize hydrogeologic features. Interpreted two‐ and three‐dimensional data coverage provides the groundwater modeler with a high‐resolution hydrogeologic framework and a quantitative estimate of framework uncertainty. This method of creating hydrogeologic frameworks improved the understanding of flow path orientation by redefining the location of the paleochannels and associated bedrock highs. The improved models reflect actual hydrogeology at a level of accuracy not achievable using previous data sets.

  18. Physically-Based Assessment of Intrinsic Groundwater Resource Vulnerability in AN Urban Catchment

    Science.gov (United States)

    Graf, T.; Therrien, R.; Lemieux, J.; Molson, J. W.

    2013-12-01

    Several methods exist to assess intrinsic groundwater (re)source vulnerability for the purpose of sustainable groundwater management and protection. However, several methods are empirical and limited in their application to specific types of hydrogeological systems. Recent studies suggest that a physically-based approach could be better suited to provide a general, conceptual and operational basis for groundwater vulnerability assessment. A novel method for physically-based assessment of intrinsic aquifer vulnerability is currently under development and tested to explore the potential of an integrated modelling approach, combining groundwater travel time probability and future scenario modelling in conjunction with the fully integrated HydroGeoSphere model. To determine the intrinsic groundwater resource vulnerability, a fully coupled 2D surface water and 3D variably-saturated groundwater flow model in conjunction with a 3D geological model (GoCAD) has been developed for a case study of the Rivière Saint-Charles (Québec/Canada) regional scale, urban watershed. The model has been calibrated under transient flow conditions for the hydrogeological, variably-saturated subsurface system, coupled with the overland flow zone by taking into account monthly recharge variation and evapotranspiration. To better determine the intrinsic groundwater vulnerability, two independent approaches are considered and subsequently combined in a simple, holistic multi-criteria-decision analyse. Most data for the model comes from an extensive hydrogeological database for the watershed, whereas data gaps have been complemented via field tests and literature review. The subsurface is composed of nine hydrofacies, ranging from unconsolidated fluvioglacial sediments to low permeability bedrock. The overland flow zone is divided into five major zones (Urban, Rural, Forest, River and Lake) to simulate the differences in landuse, whereas the unsaturated zone is represented via the model

  19. A quantitative assessment of groundwater resources in the Middle East and North Africa region

    Science.gov (United States)

    Lezzaik, Khalil; Milewski, Adam

    2017-08-01

    The Middle East and North Africa (MENA) region is the world's most water-stressed region, with its countries constituting 12 of the 15 most water-stressed countries globally. Because of data paucity, comprehensive regional-scale assessments of groundwater resources in the MENA region have been lacking. The presented study addresses this issue by using a distributed ArcGIS model, parametrized with gridded data sets, to estimate groundwater storage reserves in the region based on generated aquifer saturated thickness and effective porosity estimates. Furthermore, monthly gravimetric datasets (GRACE) and land surface parameters (GLDAS) were used to quantify changes in groundwater storage between 2003 and 2014. Total groundwater reserves in the region were estimated at 1.28 × 106 cubic kilometers (km3) with an uncertainty range between 816,000 and 1.93 × 106 km3. Most of the reserves are located within large sedimentary basins in North Africa and the Arabian Peninsula, with Algeria, Libya, Egypt, and Saudi Arabia accounting for approximately 75% of the region's total freshwater reserves. Alternatively, small groundwater reserves were found in fractured Precambrian basement exposures. As for groundwater changes between 2003 and 2014, all MENA countries except for Morocco exhibited declines in groundwater storage. However, given the region's large groundwater reserves, groundwater changes between 2003 and 2014 are minimal and represent no immediate short-term threat to the MENA region, with some exceptions. Notwithstanding this, the study recommends the development of sustainable and efficient groundwater management policies to optimally utilize the region's groundwater resources, especially in the face of climate change, demographic expansion, and socio-economic development.

  20. Anthropization of groundwater resources in the Mediterranean region: processes and challenges

    Science.gov (United States)

    Leduc, Christian; Pulido-Bosch, Antonio; Remini, Boualem

    2017-09-01

    A comprehensive overview is provided of processes and challenges related to Mediterranean groundwater resources and associated changes in recent decades. While most studies are focused thematically and/or geographically, this paper addresses different stages of groundwater exploitation in the region and their consequences. Examples emphasize the complex interactions between the physical and social dimensions of uses and evolution of groundwater. In natural conditions, Mediterranean groundwater resources represent a wide range of hydrogeological contexts, recharge conditions and rates of exploitation. They have been actively exploited for millennia but their pseudo-natural regimes have been considerably modified in the last 50 years, especially to satisfy agricultural demand (80% of total water consumption in North Africa), as well as for tourism and coastal cities. Climate variability affects groundwater dynamics but the various forms of anthropization are more important drivers of hydrological change, including changes in land use and vegetation, hydraulic works, and intense pumpings. These changes affect both the quantity and quality of groundwater at different scales, and modify the nature of hydrogeological processes, their location, timing, and intensity. The frequent cases of drastic overexploitation illustrate the fragility of Mediterranean groundwater resources and the limits of present forms of management. There is no easy way to maintain or recover sustainability, which is often threatened by short-term interests. To achieve this goal, a significant improvement in hydrogeological knowledge and closer collaboration between the various disciplines of water sciences are indispensable.

  1. Anthropization of groundwater resources in the Mediterranean region: processes and challenges

    Science.gov (United States)

    Leduc, Christian; Pulido-Bosch, Antonio; Remini, Boualem

    2017-04-01

    A comprehensive overview is provided of processes and challenges related to Mediterranean groundwater resources and associated changes in recent decades. While most studies are focused thematically and/or geographically, this paper addresses different stages of groundwater exploitation in the region and their consequences. Examples emphasize the complex interactions between the physical and social dimensions of uses and evolution of groundwater. In natural conditions, Mediterranean groundwater resources represent a wide range of hydrogeological contexts, recharge conditions and rates of exploitation. They have been actively exploited for millennia but their pseudo-natural regimes have been considerably modified in the last 50 years, especially to satisfy agricultural demand (80% of total water consumption in North Africa), as well as for tourism and coastal cities. Climate variability affects groundwater dynamics but the various forms of anthropization are more important drivers of hydrological change, including changes in land use and vegetation, hydraulic works, and intense pumpings. These changes affect both the quantity and quality of groundwater at different scales, and modify the nature of hydrogeological processes, their location, timing, and intensity. The frequent cases of drastic overexploitation illustrate the fragility of Mediterranean groundwater resources and the limits of present forms of management. There is no easy way to maintain or recover sustainability, which is often threatened by short-term interests. To achieve this goal, a significant improvement in hydrogeological knowledge and closer collaboration between the various disciplines of water sciences are indispensable.

  2. A regional groundwater-flow model for sustainable groundwater-resource management in the south Asian megacity of Dhaka, Bangladesh

    Science.gov (United States)

    Islam, Md Bayzidul; Firoz, A. B. M.; Foglia, Laura; Marandi, Andres; Khan, Abidur Rahman; Schüth, Christoph; Ribbe, Lars

    2017-01-01

    The water resources that supply most of the megacities in the world are under increased pressure because of land transformation, population growth, rapid urbanization, and climate-change impacts. Dhaka, in Bangladesh, is one of the largest of 22 growing megacities in the world, and it depends on mainly groundwater for all kinds of water needs. The regional groundwater-flow model MODFLOW-2005 was used to simulate the interaction between aquifers and rivers in steady-state and transient conditions during the period 1981-2013, to assess the impact of development and climate change on the regional groundwater resources. Detailed hydro-stratigraphic units are described according to 150 lithology logs, and a three-dimensional model of the upper 400 m of the Greater Dhaka area was constructed. The results explain how the total abstraction (2.9 million m3/d) in the Dhaka megacity, which has caused regional cones of depression, is balanced by recharge and induced river leakage. The simulated outcome shows the general trend of groundwater flow in the sedimentary Holocene aquifers under a variety of hydrogeological conditions, which will assist in the future development of a rational and sustainable management approach.

  3. A regional groundwater-flow model for sustainable groundwater-resource management in the south Asian megacity of Dhaka, Bangladesh

    Science.gov (United States)

    Islam, Md Bayzidul; Firoz, A. B. M.; Foglia, Laura; Marandi, Andres; Khan, Abidur Rahman; Schüth, Christoph; Ribbe, Lars

    2017-05-01

    The water resources that supply most of the megacities in the world are under increased pressure because of land transformation, population growth, rapid urbanization, and climate-change impacts. Dhaka, in Bangladesh, is one of the largest of 22 growing megacities in the world, and it depends on mainly groundwater for all kinds of water needs. The regional groundwater-flow model MODFLOW-2005 was used to simulate the interaction between aquifers and rivers in steady-state and transient conditions during the period 1981-2013, to assess the impact of development and climate change on the regional groundwater resources. Detailed hydro-stratigraphic units are described according to 150 lithology logs, and a three-dimensional model of the upper 400 m of the Greater Dhaka area was constructed. The results explain how the total abstraction (2.9 million m3/d) in the Dhaka megacity, which has caused regional cones of depression, is balanced by recharge and induced river leakage. The simulated outcome shows the general trend of groundwater flow in the sedimentary Holocene aquifers under a variety of hydrogeological conditions, which will assist in the future development of a rational and sustainable management approach.

  4. Fluoride contamination in groundwater resources of Alleppey, southern India

    Directory of Open Access Journals (Sweden)

    Dhanya Raj

    2017-01-01

    Full Text Available Alleppey is one of the thickly populated coastal towns of the Kerala state in southern India. Groundwater is the main source of drinking water for the 240,991 people living in this region. The groundwater is being extracted from a multi-layer aquifer system of unconsolidated to semi-consolidated sedimentary formations, which range in age from Recent to Tertiary. The public water distribution system uses dug and tube wells. Though there were reports on fluoride contamination, this study reports for the first time excess fluoride and excess salinity in the drinking water of the region. The quality parameters, like Electrical Conductivity (EC ranges from 266 to 3900 μs/cm, the fluoride content ranges from 0.68 to 2.88 mg/L, and the chloride ranges between the 5.7 to 1253 mg/L. The main water types are Na-HCO3, Na-CO3 and Na-Cl. The aqueous concentrations of F− and CO32− show positive correlation whereas F− and Ca2+ show negative correlation. The source of fluoride in the groundwater could be from dissolution of fluorapatite, which is a common mineral in the Tertiary sediments of the area. Long residence time, sediment–groundwater interaction and facies changes (Ca-HCO3 to Na-HCO3 during groundwater flow regime are the major factors responsible for the high fluoride content in the groundwater of the area. High strontium content and high EC in some of the wells indicate saline water intrusion that could be due to the excess pumping from the deeper aquifers of the area. The water quality index computation has revealed that 62% of groundwater belongs to poor quality and is not suitable for domestic purposes as per BIS and WHO standards. Since the groundwater is the only source of drinking water in the area, proper treatment strategies and regulating the groundwater extraction are required as the quality deterioration poses serious threat to human health.

  5. Ground-Water Resources of Saipan, Commonwealth of the Northern Meriana Islands

    Science.gov (United States)

    Carruth, Robert L.

    2003-01-01

    Introduction Saipan has an area of 48 mi2 and is the largest of the 14 islands in the Commonwealth of the Northern Mariana Islands (CNMI). The island is formed by volcanic rocks overlain by younger limestones. The island is situated in the western Pacific Ocean at latitude 15?12'N and longitude 145?45'E, about 3,740 mi west-southwest of Honolulu and midway between Japan and New Guinea (fig. 1). The climate on Saipan is classified as tropical marine with an average temperature of 80?F. The natural beauty of the island and surrounding waters are the basis for a growing tourist-based economy. The resulting rapid development and increases in resident and tourist populations have added stresses to the island's limited water supplies. Freshwater resources on Saipan are not readily observable because, aside from the abundant rainfall, most freshwater occurs as ground water. Fresh ground water is found in aquifers composed mainly of fragmental limestones. About 90 percent of the municipal water supply comes from 140 shallow wells that withdraw about 11 Mgal/d. The chloride concentration of water withdrawn from production wells ranges from less than 100 mg/L for wells in the Akgak and Capital Hill well fields, to over 2,000 mg/L from wells in the Puerto Rico, Maui IV, and Marpi Quarry well fields. The chloride concentrations and rates of ground-water production are not currently adequate for providing island residents with a potable 24-hour water supply and future demands are expected to be higher. To better understand the ground-water resources of the island, and water resources on tropical islands in general, the U.S. Geological Survey (USGS) entered into a cooperative program with the Commonwealth Utilities Corporation (CUC). The objective of the program, initiated in 1989, is to assess the ground-water resources of Saipan and to make hydrologic information available to the CUC in support of their ongoing efforts to improve the quality and quantity of the municipal water

  6. Application of natural resource valuation concepts for development of sustainable remediation plans for groundwater.

    Science.gov (United States)

    Connor, John A; Paquette, Shawn; McHugh, Thomas; Gie, Elaine; Hemingway, Mark; Bianchi, Gino

    2017-04-07

    This paper explores the application of natural resource assessment and valuation procedures as a tool for developing groundwater remediation strategies that achieve the objectives for health and environmental protection, in balance with considerations of economic viability and conservation of natural resources. The natural resource assessment process, as applied under U.S. and international guidelines, entails characterization of groundwater contamination in terms of the pre-existing beneficial services of the impacted resource, the loss of these services caused by the contamination, and the measures and associated costs necessary to restore or replace the lost services. Under many regulatory programs, groundwater remediation objectives assume that the impacted groundwater may be used as a primary source of drinking water in the future, even if not presently in use. In combination with a regulatory preference for removal or treatment technologies, this assumed exposure, while protective of human health, can drive the remedy selection process toward remedies that may not be protective of the groundwater resource itself or of the other natural resources (energy, materials, chemicals, etc.) that may be consumed in the remediation effort. To achieve the same health and environmental protection goals under a sustainable remediation framework, natural resource assessment methods can be applied to restore the lost services and preserve the intact services of the groundwater so as to protect both current and future users of that resource. In this paper, we provide practical guidelines for use of natural resource assessment procedures in the remedy selection process and present a case study demonstrating the use of these protocols for development of sustainable remediation strategies. Copyright © 2017 The Authors. Published by Elsevier Ltd.. All rights reserved.

  7. Island groundwater resources, impacts of abstraction and a drying climate: Rottnest Island, Western Australia

    Science.gov (United States)

    Bryan, Eliza; Meredith, Karina T.; Baker, Andy; Post, Vincent E. A.; Andersen, Martin S.

    2016-11-01

    Coastal aquifers provide a source of water for more than one billion people, with island freshwater lenses being some of the most vulnerable coastal groundwater systems due to their susceptibility to saltwater intrusion. Basic hydrogeological and hydrochemical knowledge regarding the recharge and salinisation processes of freshwater lenses is important to ensure sustainable utilisation, especially considering possible climate change effects. This paper makes an assessment of the fate of a freshwater lens in a drying climate through a comparison of current and historic hydrochemical data, which to the author's knowledge is unique to this study. Fresh groundwater stable isotope signatures (δ18O, δ2H) reflect local amount weighted rainfall signatures (δ18O: -3.8‰; δ2H: -15.1‰), and confirm rainfall as the origin of fresh groundwater (δ18O: -4.47 to -3.82‰; δ2H: -20.0 to -16.6‰). Mixing with seawater was identified through enriched groundwater δ18O and δ2H signatures (maximum values of -0.36‰ and -1.4‰ respectively) compared to local rainfall and higher salinity (maximum 29,267 mg/L Total Dissolved Solids (TDS)) in a number of monitoring wells around the freshwater lens. Enhanced seawater intrusion detected in the northern section of the lens area was identified through significantly increased TDS values over the last 20-40 years, with increases of up to 3000% observed between 1990 and 2014. A reduction in the extent of freshwater by approximately 1 km2 was identified since 1977, which was found to be primarily caused by a reduction in recharge to the freshwater lens due to a ∼20% decline in winter rainfall in the south-west Western Australian region since the mid 1960s. Groundwater abstraction was found to equate to between 5% and 9% of the estimated recharge for the island, and is not a significant factor in the reduction of the lens extent compared to the observed decline in rainfall recharge. Interestingly, seawater intrusion into the fresh

  8. The Maryland Coastal Plain Aquifer Information System: A GIS-based tool for assessing groundwater resources

    Science.gov (United States)

    Andreasen, David C.; Nardi, Mark R.; Staley, Andrew W.; Achmad, Grufron; Grace, John W.

    2016-01-01

    Groundwater is the source of drinking water for ∼1.4 million people in the Coastal Plain Province of Maryland (USA). In addition, groundwater is essential for commercial, industrial, and agricultural uses. Approximately 0.757 × 109 L d–1 (200 million gallons/d) were withdrawn in 2010. As a result of decades of withdrawals from the coastal plain confined aquifers, groundwater levels have declined by as much as 70 m (230 ft) from estimated prepumping levels. Other issues posing challenges to long-term groundwater sustainability include degraded water quality from both man-made and natural sources, reduced stream base flow, land subsidence, and changing recharge patterns (drought) caused by climate change. In Maryland, groundwater supply is managed primarily by the Maryland Department of the Environment, which seeks to balance reasonable use of the resource with long-term sustainability. The chief goal of groundwater management in Maryland is to ensure safe and adequate supplies for all current and future users through the implementation of appropriate usage, planning, and conservation policies. To assist in that effort, the geographic information system (GIS)–based Maryland Coastal Plain Aquifer Information System was developed as a tool to help water managers access and visualize groundwater data for use in the evaluation of groundwater allocation and use permits. The system, contained within an ESRI ArcMap desktop environment, includes both interpreted and basic data for 16 aquifers and 14 confining units. Data map layers include aquifer and ­confining unit layer surfaces, aquifer extents, borehole information, hydraulic properties, time-series groundwater-level data, well records, and geophysical and lithologic logs. The aquifer and confining unit layer surfaces were generated specifically for the GIS system. The system also contains select groundwater-quality data and map layers that quantify groundwater and surface-water withdrawals. The aquifer

  9. Ground-water resources of Riverton irrigation project area, Wyoming

    Science.gov (United States)

    Morris, Donald Arthur; Hackett, O.M.; Vanlier, K.E.; Moulder, E.A.; Durum, W.H.

    1959-01-01

    The Riverton irrigation project area is in the northwestern part of the Wind River basin in west-central Wyoming. Because the annual precipitation is only about 9 inches, agriculture, which is the principal occupation in the area, is dependent upon irrigation. Irrigation by surface-water diversion was begum is 1906; water is now supplied to 77,716 acres and irrigation has been proposed for an additional 31,344 acres. This study of the geology and ground-water resources of the Riverton irrigation project, of adjacent irrigated land, and of nearby land proposed for irrigation was begun during the summer of 1948 and was completed in 1951. The purpose of the investigation was to evaluate the ground-water resources of the area and to study the factors that should be considered in the solution of drainage and erosional problems within the area. The Riverton irrigation project area is characterized by flat to gently sloping stream terraces, which are flanked by a combination of badlands, pediment slopes, and broad valleys. These features were formed by long-continued erosion in an arid climate of the essentially horizontal, poorly consolidated beds of the Wind River formation. The principal streams of the area flow south-eastward. Wind River and Fivemile Creek are perennial streams and the others are intermittent. Ground-water discharge and irrigation return flow have created a major problem in erosion control along Fivemile Creek. Similar conditions might develop along Muddy and lower Cottonwood Creeks when land in their drainage basins is irrigated. The bedrock exposed in the area ranges in age from Late Cretaceous to early Tertiary (middle Eocene). The Wind River formation of early and middle Eocene age forms the uppermost bedrock formation in the greater part of the area. Unconsolidated deposits of Quaternary age, which consist of terrace gravel, colluvium, eolian sand and silt. and alluvium, mantle the Wind River formation in much of the area. In the irrigated parts

  10. Irrigator responses to groundwater resource management in northern Victoria, southeastern Australia

    Science.gov (United States)

    Gill, Bruce C.; Webb, John; Wilkinson, Roger; Cherry, Don

    2014-10-01

    In northern Victoria, farmers are the biggest users of groundwater and therefore the main stakeholders in plans that seek to sustainably manage the resource. Interviews with 30 irrigation farmers in two study areas, analysed using qualitative social research methods, showed that the overwhelming majority of groundwater users agreed with the need for groundwater management and thought that the current plans had achieved sustainable resource use. The farmers also expressed a strong need for clear technical explanations for management decisions, in particular easily understood water level data. The social licence to implement the management plans arose through effective consultation with the community during plan development. Several additional factors combined to gain acceptance for the plans: good data on groundwater usage and aquifer levels is available; irrigation farmers had been exposed to usage restrictions since the late 1990s; an ‘adaptive’ management approach is in use which allowed refinements to be readily incorporated and fortuitously, plan development coincided with the 1998-2009 drought, when declines in groundwater levels reinforced the usefulness of the plans. The imposition of a nation-wide water use reduction plan in 2012 had relatively little impact in Victoria because of the early implementation of effective groundwater management plans. However, economic difficulties that reduce groundwater users’ capacity to pay groundwater management charges mean that the future of the plans in Victoria is not assured. Nevertheless, the high level of trust that exists between Victorian irrigation farmers and the management agencies suggests that the continued use of a consultative approach will continue to produce workable outcomes. Lessons from the Victorian experience may be difficult to apply in other areas of groundwater use in Australia and overseas, where there may be a quite different history of development and culture of groundwater management.

  11. Hydrogeology and Groundwater Resources of the Coastal Aquifers of Southeastern Massachusetts

    Science.gov (United States)

    Masterson, John P.; Walter, Donald A.

    2009-01-01

    The glacially derived aquifer systems of southeastern Massachusetts compose the largest groundwater reservoir in the State. Population increases, land-use changes, and climate change in this area could lead to three primary environmental effects that relate directly to groundwater resources - (1) increases in pumping that could adversely affect environmentally sensitive groundwater-fed surface waters, such as ponds, streams, and wetlands; (2) changes in land use that could affect the quality of water in the aquifer; and (3) changes in precipitation and mean sea level that can affect water levels, streamflow, and the position of the freshwater/saltwater boundary. Therefore, understanding groundwater flow and the factors that can affect it is critical to managing and protecting this vital resource.

  12. Irrigated agriculture and groundwater resources - towards an integrated vision and sustainable relationship.

    Science.gov (United States)

    Foster, Stephen; Garduño, Héctor

    2013-01-01

    Globally, irrigated agriculture is the largest abstractor, and predominant consumer, of groundwater resources, with large groundwater-dependent agro-economies now having widely evolved especially in Asia. Such use is also causing resource depletion and degradation in more arid and drought-prone regions. In addition crop cultivation practices on irrigated land exert a major influence on groundwater recharge. The interrelationship is such that cross-sector action is required to agree more sustainable land and water management policies, and this paper presents an integrated vision of the challenges in this regard. It is recognised that 'institutional arrangements' are critical to the local implementation of management policies, although the focus here is limited to the conceptual understanding needed for formulation of an integrated policy and some practical interventions required to promote more sustainable groundwater irrigation.

  13. The thermal impact of subsurface building structures on urban groundwater resources - A paradigmatic example.

    Science.gov (United States)

    Epting, Jannis; Scheidler, Stefan; Affolter, Annette; Borer, Paul; Mueller, Matthias H; Egli, Lukas; García-Gil, Alejandro; Huggenberger, Peter

    2017-10-15

    Shallow subsurface thermal regimes in urban areas are increasingly impacted by anthropogenic activities, which include infrastructure development like underground traffic lines as well as industrial and residential subsurface buildings. In combination with the progressive use of shallow geothermal energy systems, this results in the so-called subsurface urban heat island effect. This article emphasizes the importance of considering the thermal impact of subsurface structures, which commonly is underestimated due to missing information and of reliable subsurface temperature data. Based on synthetic heat-transport models different settings of the urban environment were investigated, including: (1) hydraulic gradients and conductivities, which result in different groundwater flow velocities; (2) aquifer properties like groundwater thickness to aquitard and depth to water table; and (3) constructional features, such as building depths and thermal properties of building structures. Our results demonstrate that with rising groundwater flow velocities, the heat-load from building structures increase, whereas down-gradient groundwater temperatures decrease. Thermal impacts on subsurface resources therefore have to be related to the permeability of aquifers and hydraulic boundary conditions. In regard to the urban settings of Basel, Switzerland, flow velocities of around 1 md(-1) delineate a marker where either down-gradient temperature deviations or heat-loads into the subsurface are more relevant. Furthermore, no direct thermal influence on groundwater resources should be expected for aquifers with groundwater thicknesses larger 10m and when the distance of the building structure to the groundwater table is higher than around 10m. We demonstrate that measuring temperature changes down-gradient of subsurface structures is insufficient overall to assess thermal impacts, particularly in urban areas. Moreover, in areas which are densely urbanized, and where groundwater flow

  14. Groundwater Resources Assessment For Joypurhat District Using Mathematical Modelling Technique

    Directory of Open Access Journals (Sweden)

    Md. Iquebal Hossain

    2015-06-01

    Full Text Available In this study potential recharge as well as groundwater availability for 5 Upazillas (Akkelpur, Kalai, Joypurhat Sadar, Khetlal and Panchbibi of Joypurhat districts has been estimated using MIKE SHE modelling tools. The main aquifers of the study area are dominated by medium sands, medium and coarse sands with little gravels. The top of aquifers ranges from 15 m to 24 m and the screenable thickness of aquifers range from 33 m to 46 m within the depth range from 57 m to 87 m. Heavy abstraction of groundwater for agricultural, industrial and domestic uses results in excessive lowering of water table making the shallow and hand tubewells inoperable in the dry season. The upazilawise potential recharge for the study area was estimated through mathematical model using MIKE SHE modelling tools in an integrated approach. The required data were collected from the different relevant organisations. The potential recharge of the present study varies from 452 mm to 793 mm. Maximum depth to groundwater table in most of the places occurs at the end of April. At this time, groundwater table in most of the part of Kalai, Khetlal, Akkelpur and Panchbibi goes below suction limit causing HTWs and STWs partially/fully in operable.

  15. Impact of Irrigated Agroecosystems on Groundwater Resources in the US High Plains and North China Plain

    Science.gov (United States)

    Scanlon, B. R.; Longuevergne, L.; Cao, G.; Shen, Y.; Gates, J. B.; Reedy, R. W.; Zheng, C.

    2010-12-01

    Overabstraction of groundwater for irrigation in semiarid regions is depleting the worlds’ largest aquifers at much greater rates than these aquifers are being replenished by recharge. This study evaluates groundwater sustainability in the US High Plains (US HP) and North China Plain (NCP) where intensive irrigation has resulted in large water table declines. A variety of approaches were used to evaluate impacts of irrigation on groundwater resources, including GRACE satellite data, unsaturated zone profiling, and groundwater quantity and quality data. Cultivation (40% of area) and irrigation (12%) are less intensive in the US HP than in the NCP (80% cultivated, 50% irrigated). Irrigation is estimated to consume ~97% of groundwater resources in the US HP and ~70% in the NCP. Although only ~10% of groundwater resources has been consumed in the US HP (330 km3 out of 3,900 km3), the problem lies in the uneven spatial distribution. Groundwater depletion is greatest in the Central High Plains (CHP) where water table declines of up to 1.5 m/yr have been recorded in individual wells and regional declines of up to 30 m have been found over a 7,000 km2 area since irrigation began in the 1950s to 1960s. This depletion indicates an irrigation deficit of ~75 mm/yr over 60 yr (specific yield 15%). Recharge rates in the CHP are extremely low (median ~10 mm/yr) with reductions in groundwater storage exceeding recharge by ~10 times. High correlations between GRACE and measured water storage changes (R = 0.7 - 0.8) show that the satellite can accurately track regional changes in water storage. Groundwater in the NCP has declined from a depth of ~1 m in the 1960s to 20 to 40 m in the Piedmont region since expansion of irrigation beginning in the 1970s. Groundwater level declines in individual hydrographs range from 0.5 to 1.0 m/yr, indicating irrigation deficits ranging from 100 to 200 mm/yr (specific yield 20%). Lower groundwater storage changes from GRACE satellites relative to

  16. Assessment of Groundwater Resources of Dauphin Island and its Connection to Urban Sprawl and Economic Growth

    Science.gov (United States)

    Petty, K. S.

    2009-12-01

    Dauphin Island is a barrier island about 28 miles south of Mobile, Alabama. The island relies heavily on the shallow aquifer underlying the barrier island. Worldwide, the largest volume of water used for human consumption and use comes from groundwater resources. On barrier islands such as Dauphin Island, the proportion of water used by humans coming from groundwater resources is even higher. Additionally, tourism is very important to the economy of Dauphin Island, and the hotels and tourist attractions rely on groundwater. Because of the large influx of people there are peaks in water demand during tourist season. The goal of this project is to quantify the impacts of urban growth on the aquifer and provide an estimate for sustainable withdrawal rates. The project will be carried out in two main phases. In the first phase a water resource assessment and analysis will be conducted using the SEAWAT model. SEAWAT simulates three-dimensional variable-density ground-water flow coupled with multi-species solute and heat transport. In the second phase the calibrated groundwater model for the island will be used to perform a scenario analysis which would help link groundwater availability with urban sprawl. In this paper we will describe the research methodology and procedures that will be used in the project.

  17. Groundwater resources management through the applications of simulation modeling: a review.

    Science.gov (United States)

    Singh, Ajay

    2014-11-15

    The global population is increasing rapidly and expected to touch the 9.5 billion mark by 2050 from the current 7.2 billion. The management of the groundwater resources is a challenging task worldwide against the backdrop of the growing water demand for industrial, agricultural, and domestic uses and shrinking resources. Moreover, this task has been hampered significantly due to declining/rising groundwater levels and associated contamination. A broad range of solutions could be considered to address the aforementioned problems of groundwater management, but the effectiveness of all the solutions and their combinations cannot be verified with field experiments. Given their predictive capability, simulation models are often the only viable means of providing input to management decisions, as they can forecast the likely impacts of a particular water management strategy. This paper presents a comprehensive review on the simulation modeling applications for the management of groundwater resources. The past papers on the overview of groundwater simulation models, use of remote sensing and GIS in groundwater modeling, and application of simulation models in arid and semiarid regions are described in detail. Conclusions are drawn where gaps exist and more research needs to be focused. Copyright © 2014 Elsevier B.V. All rights reserved.

  18. Preliminary Prioritization of California Oil and Gas Fields for Regional Groundwater Monitoring Based on Intensity of Petroleum Resource Development and Proximity to Groundwater Resources

    Science.gov (United States)

    Davis, T. A.; Landon, M. K.; Bennett, G.

    2016-12-01

    The California State Water Resources Control Board is collaborating with the U.S. Geological Survey to implement a Regional Monitoring Program (RMP) to assess where and to what degree groundwater resources may be at risk of contamination from oil and gas development activities including stimulation, well integrity issues, produced water ponds, and underground injection. A key issue in the implementation of the RMP is that the state has 487 onshore oil fields covering 8,785 square kilometers but detailed characterization work can only be done in a few oil fields annually. The first step in the RMP is to prioritize fields using available data that indicate potential risk to groundwater from oil and gas development, including vertical proximity of groundwater and oil/gas resources, density of petroleum and water wells, and volume of water injected in oil fields. This study compiled data for these factors, computed summary metrics for each oil field, analyzed statewide distributions of summary metrics, used those distributions to define relative categories of potential risk for each factor, and combined these into an overall priority ranking. Aggregated results categorized 22% (107 fields) of the total number of onshore oil and gas fields in California as high priority, 23% as moderate priority, and 55% as low priority. On an area-weighted basis, 41% of the fields ranked high, 30% moderate, and 29% low, highlighting that larger fields tend to have higher potential risk because of greater intensity of development, sometimes coupled with closer proximity to groundwater. More than half of the fields ranked as high priority were located in the southern Central Valley or the Los Angeles Basin. The prioritization does not represent an assessment of groundwater risk from oil and gas development; rather, such assessments are planned to follow based on detailed analysis of data from the RMP near the oil fields selected for study in the future.

  19. Large scale mapping of groundwater resources using a highly integrated set of tools

    DEFF Research Database (Denmark)

    Søndergaard, Verner; Auken, Esben; Christiansen, Anders Vest

    platforms (e.g. SkyTEM) have made large-scale mapping attractive and affordable in the planning and administration of groundwater resources. The handling and optimized use of huge amounts of geophysical data covering large areas has also required a comprehensive database, where data can easily be stored......The aim of this abstract is to give a short description of the essential ideas of the Danish national strategy for large scale mapping of the groundwater resources.Emphasis will be put on a description of the advantages obtained by combining acquirement of spatially dense geophysical data covering...... large areas with information from an optimum number of new investigation boreholes, existing boreholes, logs and water samples to get an integrated and detailed description of the groundwater resources and their vulnerability.Development of more time efficient and airborne geophysical data acquisition...

  20. Strontium isotope geochemistry of alluvial groundwater: a tracer for groundwater resources characterisation

    Directory of Open Access Journals (Sweden)

    P. Négrel

    2004-01-01

    Full Text Available This study presents strontium isotope and major ion data of shallow groundwater and river water from the Ile du Chambon catchment, located on the Allier river in the Massif Central (France. There are large variations in the major-element contents in the surface- and groundwater. Plotting of Na vs. Cl contents and Ca, Mg, NO3, K, SO4, HCO3, Sr concentrations reflect water–rock interaction (carbonate dissolution for Ca, Mg, HCO3 and Sr because the bedrock contains marly limestones, agricultural input (farming and fertilising and sewage effluents (for NO3, K, SO4, although some water samples are unpolluted. Sr contents and isotope ratios (87Sr/86Sr vary from 0.70892 to 0.71180 along the hydrological cycle in the groundwater agree with previous work on groundwater in alluvial aquifers in the Loire catchment. The data plot along three directions in a 87Sr/86Sr v. 1/Sr diagram as a result of mixing, involving at least three geochemical signatures–Allier river water, and two distinct signatures that might be related to different water-rock interactions in the catchment. Mixing proportions are calculated and discussed. The alluvial aquifer of the Ile du Chambon catchment is considered, within the Sr isotope systematic, in a larger scheme that includes several alluvial aquifers of the Loire Allier catchment. Keywords: : Loire river, major and trace elements, Sr isotopic ratio, alluvial aquifer, hydrology

  1. How to quantify realization of WFD-objectives of groundwater resources?

    Science.gov (United States)

    van den Brink, Cors; Wuijts, Susanne; Boekhold, Sandra

    2016-04-01

    Groundwater is a major resource for drinking water in the Netherlands . Evaluation of the EU Water Framework Directive (EU-WFD) showed that protection of this valuable resource needs improval. Drinking Water Protection Files were set up to assess risks and identify actions needed regarding the identification and implementation of measures enhancing the protection level of groundwater resources in groundwater protection areas. Evaluation of these first generation protection files showed several issues for further improvement, among others on effectiveness of measures. In workshops we analyzed and discussed the feasibility to quantify the impact of measures by combining information on groundwater quality with experiences of stakeholders with success and failure factors. Although there is still a way to go in the quantification of the impact of measures regarding the EU-WFD objectives, these workshops contributed to insight in i) the joint experience we gained on measures and their implementation at different spatial scales, ii) the distribution of the measures over identified risks (i.e. nitrate, pesticides and emerging contaminants) and iii) the estimated contribution of methods to reach the WFD objectives and knowledge gaps. From discussions in the national working group on protection files, it became clear that this analysis is a valuable first step in prioritizing and implementing the measures. Adequate monitoring of implemented measures will additionally contribute to a more quantitative assessment of the realization of the objectives of groundwater resources.

  2. Quality of our groundwater resources: arsenic and fluoride

    Science.gov (United States)

    Nordstrom, D. Kirk

    2011-01-01

    Groundwater often contains arsenic or fluoride concentrations too high for drinking or cooking. These constituents, often naturally occurring, are not easy to remove. The right combination of natural or manmade conditions can lead to elevated arsenic or fluoride which includes continental source rocks, high alkalinity and pH, reducing conditions for arsenic, high phosphate, high temperature and high silica. Agencies responsible for safe drinking water should be aware of these conditions, be prepared to monitor, and treat if necessary.

  3. Focus on CSIR research in water resources: Groundwater resistivity

    CSIR Research Space (South Africa)

    Colvin, C

    2007-08-01

    Full Text Available group to characterise the subsurface. This includes delineating drilling positions for water supply pur- poses (changes in both porosity and water saturation); defining pollution plumes around waste sites (changes in salinity of the groundwater... on the research project into aquifer dependant ecosystems in South Africa. The Langebaan Lagoon, West Coast National Park, has been classified as a wetland of international importance in terms of the Ramsar Convention because of its diverse bird life...

  4. Computation of groundwater resources and recharge in Chithar River Basin, South India.

    Science.gov (United States)

    Subramani, T; Babu, Savithri; Elango, L

    2013-01-01

    Groundwater recharge and available groundwater resources in Chithar River basin, Tamil Nadu, India spread over an area of 1,722 km(2) have been estimated by considering various hydrological, geological, and hydrogeological parameters, such as rainfall infiltration, drainage, geomorphic units, land use, rock types, depth of weathered and fractured zones, nature of soil, water level fluctuation, saturated thickness of aquifer, and groundwater abstraction. The digital ground elevation models indicate that the regional slope of the basin is towards east. The Proterozoic (Post-Archaean) basement of the study area consists of quartzite, calc-granulite, crystalline limestone, charnockite, and biotite gneiss with or without garnet. Three major soil types were identified namely, black cotton, deep red, and red sandy soils. The rainfall intensity gradually decreases from west to east. Groundwater occurs under water table conditions in the weathered zone and fluctuates between 0 and 25 m. The water table gains maximum during January after northeast monsoon and attains low during October. Groundwater abstraction for domestic/stock and irrigational needs in Chithar River basin has been estimated as 148.84 MCM (million m(3)). Groundwater recharge due to monsoon rainfall infiltration has been estimated as 170.05 MCM based on the water level rise during monsoon period. It is also estimated as 173.9 MCM using rainfall infiltration factor. An amount of 53.8 MCM of water is contributed to groundwater from surface water bodies. Recharge of groundwater due to return flow from irrigation has been computed as 147.6 MCM. The static groundwater reserve in Chithar River basin is estimated as 466.66 MCM and the dynamic reserve is about 187.7 MCM. In the present scenario, the aquifer is under safe condition for extraction of groundwater for domestic and irrigation purposes. If the existing water bodies are maintained properly, the extraction rate can be increased in future about 10% to 15%.

  5. Issues of Sustainability of Coastal Groundwater Resources: Benin, West Africa

    Directory of Open Access Journals (Sweden)

    Andrew D. Mullen

    2010-08-01

    Full Text Available The largest city in Benin, West Africa (Cotonou, is reliant upon groundwater for its public water supply. This groundwater is derived from the Godomey well field which is located approximately 5 Km north of the coast of the Atlantic Ocean and in close proximity to Lake Nokoue—a shallow lake containing water with elevated concentration of chloride and other elements. Historical data indicate increased chloride concentration in a number of wells nearest to the lake, with unknown contribution from groundwater encroachment from the coastal area. Hence, there is substantial interest in better characterizing this groundwater system for the purpose of determining appropriate management practices and degree of sustainability. Among the efforts attempted to date are a series of numerical models ranging from assessment of flow to a recent effort to include density-dependent transport from the lake. In addition, substantial field characterization has been pursued including assessment of shallow water chemistry along the region of the coastal lagoon and border of the lake, characterization of hydraulic response to pumpage in the aquifer system, estimation of the distribution of electrical resistivity with depth along the coastal lagoons, and installation of multi-level piezometers at seven locations in the lake. When integrated across methods, these numerical and field results indicate that the lake remains a primary concern in terms of a source of salinity in the aquifer. Further, the coastal region appears to be more complex than previously suggested and may represent a future source of salt-water encroachment as suggested by current presence of saline waters at relatively shallow depths along the coast. Finally, hydraulic testing suggests that both natural and pumping-based fluctuations in water levels are present in this system. Substantial additional characterization and modeling efforts may provide a significantly greater understanding of the

  6. Geologic and geophysical models for Osage County, Oklahoma, with implications for groundwater resources

    Science.gov (United States)

    Hudson, Mark R.; Smith, David V.; Pantea, Michael P.; Becker, Carol J.

    2016-06-16

    This report summarizes a three-dimensional (3-D) geologic model that was constructed to provide a framework to investigate groundwater resources of the Osage Nation in northeastern Oklahoma. This report also presents an analysis of an airborne electromagnetic (AEM) survey that assessed the spatial variation of electrical resistivity to depths as great as 300 meters in the subsurface. The report and model provide support for a countywide assessment of groundwater resources, emphasizing the Upper Pennsylvanian rock units in the shallow subsurface of central and eastern Osage County having electrical resistivity properties that may indicate aquifers.

  7. Groundwater resource vulnerability and spatial variability of nitrate contamination: Insights from high density tubewell monitoring in a hard rock aquifer.

    Science.gov (United States)

    Buvaneshwari, Sriramulu; Riotte, Jean; Sekhar, M; Mohan Kumar, M S; Sharma, Amit Kumar; Duprey, Jean Louis; Audry, Stephane; Giriraja, P R; Praveenkumarreddy, Yerabham; Moger, Hemanth; Durand, Patrick; Braun, Jean-Jacques; Ruiz, Laurent

    2017-02-01

    Agriculture has been increasingly relying on groundwater irrigation for the last decades, leading to severe groundwater depletion and/or nitrate contamination. Understanding the links between nitrate concentration and groundwater resource is a prerequisite for assessing the sustainability of irrigated systems. The Berambadi catchment (ORE-BVET/Kabini Critical Zone Observatory) in Southern India is a typical example of intensive irrigated agriculture and then an ideal site to study the relative influences of land use, management practices and aquifer properties on NO3 spatial distribution in groundwater. The monitoring of >200 tube wells revealed nitrate concentrations from 1 to 360mg/L. Three configurations of groundwater level and elevation gradient were identified: i) NO3 hot spots associated to deep groundwater levels (30-60m) and low groundwater elevation gradient suggest small groundwater reserve with absence of lateral flow, then degradation of groundwater quality due to recycling through pumping and return flow; ii) high groundwater elevation gradient, moderate NO3 concentrations suggest that significant lateral flow prevented NO3 enrichment; iii) low NO3 concentrations, low groundwater elevation gradient and shallow groundwater indicate a large reserve. We propose that mapping groundwater level and gradient could be used to delineate zones vulnerable to agriculture intensification in catchments where groundwater from low-yielding aquifers is the only source of irrigation. Then, wells located in low groundwater elevation gradient zones are likely to be suitable for assessing the impacts of local agricultural systems, while wells located in zones with high elevation gradient would reflect the average groundwater quality of the catchment, and hence should be used for regional mapping of groundwater quality. Irrigation with NO3 concentrated groundwater induces a "hidden" input of nitrogen to the crop which can reach 200kgN/ha/yr in hotspot areas, enhancing

  8. Evaluation of groundwater resources in a tiny Andrott Island, Union Territory of Lakshadweep, India.

    Science.gov (United States)

    Singh, V S; Sarwade, D V; Mondal, N C; Nanadakumar, M V; Singh, B

    2009-11-01

    Lakshadweep is a group of 36 coral islands scattered in the Arabian Sea off the western coast of India. On such small tiny islands, groundwater is the only source of fresh water for the islanders. Due to the growing population on these islands, demand for fresh water is also increasing and on the other side the peculiar hydrologic, geologic and geomorphic features restrict the availability of groundwater. Therefore, a proper understanding of the groundwater condition is important in order to meet this increasing demand and also to formulate future development and management strategies. Detailed hydrogeological, geophysical and hydrochemical studies have been carried out to identify potential fresh groundwater resources and quantify vulnerable parts of Andrott Island, Union Territory of Lakshadweep. Systematic collection and analysis of hydrological, geophysical and hydrochemical data reveal that fresh groundwater is only available between 2.5 to 5.0 m depths and provide an early sign of deterioration in groundwater quality in the peripheral parts of eastern and western coasts of this island. It suggests immediate measures for arresting the deterioration in groundwater quality as well as augmentation for restoration of aquifer in some parts of the island.

  9. Groundwater modeling in integrated water resources management--visions for 2020.

    Science.gov (United States)

    Refsgaard, Jens Christian; Højberg, Anker Lajer; Møller, Ingelise; Hansen, Martin; Søndergaard, Verner

    2010-01-01

    Groundwater modeling is undergoing a change from traditional stand-alone studies toward being an integrated part of holistic water resources management procedures. This is illustrated by the development in Denmark, where comprehensive national databases for geologic borehole data, groundwater-related geophysical data, geologic models, as well as a national groundwater-surface water model have been established and integrated to support water management. This has enhanced the benefits of using groundwater models. Based on insight gained from this Danish experience, a scientifically realistic scenario for the use of groundwater modeling in 2020 has been developed, in which groundwater models will be a part of sophisticated databases and modeling systems. The databases and numerical models will be seamlessly integrated, and the tasks of monitoring and modeling will be merged. Numerical models for atmospheric, surface water, and groundwater processes will be coupled in one integrated modeling system that can operate at a wide range of spatial scales. Furthermore, the management systems will be constructed with a focus on building credibility of model and data use among all stakeholders and on facilitating a learning process whereby data and models, as well as stakeholders' understanding of the system, are updated to currently available information. The key scientific challenges for achieving this are (1) developing new methodologies for integration of statistical and qualitative uncertainty; (2) mapping geological heterogeneity and developing scaling methodologies; (3) developing coupled model codes; and (4) developing integrated information systems, including quality assurance and uncertainty information that facilitate active stakeholder involvement and learning.

  10. Evaluation model coupling exploitable groundwater resources and land subsidence control in regional loose sediments

    Science.gov (United States)

    Luo, Z. J.; Zhao, S. J.; Jin, WZ; Ma, Q. S.; Wu, X. H.

    2016-08-01

    The loose sediments in the Yangtze River Delta, the North China Plain, the plain of Northern Jiangsu and other districts in China are of great thickness, complex in structure and abundant in groundwater. Groundwater overexploitation easily results in geological disasters of land subsidence. Aiming at the issues, assessment models coupling exploitable groundwater resources and land subsidence control in regional loose sediments were brought up in this paper. The two models were: (1) a three dimensional groundwater seepage model with land subsidence based on the one dimensional Terzaghi consolidation theory; (2) a three dimensional full coupling model on groundwater seepage and land subsidence based on the Biot consolidation theory to simulate and calculate. It can be used to simulate and calculate the problems in real situations. Thus, the groundwater seepage and land subsidence were coupled together in the model to evaluate the amount of exploitable groundwater under the specific requirements of land subsidence control. The full coupling model, which considers the non-linear characteristics of soil mass and the dynamic changes of soil permeability with stress state based on the Biot consolidation theory, is more coincident with the variation characteristics of the hydraulic and mechanical properties of soil mass during the pumping process, making the evaluation results more scientific and reasonable.

  11. Groundwater quality and depletion in the Indo-Gangetic Basin mapped from in situ observations

    Science.gov (United States)

    MacDonald, A. M.; Bonsor, H. C.; Ahmed, K. M.; Burgess, W. G.; Basharat, M.; Calow, R. C.; Dixit, A.; Foster, S. S. D.; Gopal, K.; Lapworth, D. J.; Lark, R. M.; Moench, M.; Mukherjee, A.; Rao, M. S.; Shamsudduha, M.; Smith, L.; Taylor, R. G.; Tucker, J.; van Steenbergen, F.; Yadav, S. K.

    2016-10-01

    Groundwater abstraction from the transboundary Indo-Gangetic Basin comprises 25% of global groundwater withdrawals, sustaining agricultural productivity in Pakistan, India, Nepal and Bangladesh. Recent interpretations of satellite gravity data indicate that current abstraction is unsustainable, yet these large-scale interpretations lack the spatio-temporal resolution required to govern groundwater effectively. Here we report new evidence from high-resolution in situ records of groundwater levels, abstraction and groundwater quality, which reveal that sustainable groundwater supplies are constrained more by extensive contamination than depletion. We estimate the volume of groundwater to 200 m depth to be >20 times the combined annual flow of the Indus, Brahmaputra and Ganges, and show the water table has been stable or rising across 70% of the aquifer between 2000 and 2012. Groundwater levels are falling in the remaining 30%, amounting to a net annual depletion of 8.0 +/- 3.0 km3. Within 60% of the aquifer, access to potable groundwater is restricted by excessive salinity or arsenic. Recent groundwater depletion in northern India and Pakistan has occurred within a longer history of groundwater accumulation from extensive canal leakage. This basin-wide synthesis of in situ groundwater observations provides the spatial detail essential for policy development, and the historical context to help evaluate recent satellite gravity data.

  12. Resource Letter OSE-1: Observing Solar Eclipses

    Science.gov (United States)

    Pasachoff, Jay M.; Fraknoi, Andrew

    2017-07-01

    This Resource Letter provides a guide to the available literature, listing selected books, articles, and online resources about scientific, cultural, and practical issues related to observing solar eclipses. It is timely, given that a total solar eclipse will cross the continental United States on August 21, 2017. The next total solar eclipse path crossing the U.S. and Canada will be on April 8, 2024. In 2023, the path of annularity of an annular eclipse will cross Mexico, the United States, and Canada, with partial phases visible throughout those countries.

  13. Reducing the environmental impacts of reverse osmosis desalination by using brackish groundwater resources.

    Science.gov (United States)

    Muñoz, Ivan; Fernández-Alba, Amadeo Rodríguez

    2008-02-01

    The aim of the present work is to find out whether or not, and to what extent, the environmental impacts of reverse osmosis desalination are reduced when brackish groundwater is used instead of sea water. In order to answer this question, the Life-Cycle Assessment (LCA) methodology is used, and two water production plants are compared. The brackish groundwater scenario is based on a plant located in Almería (southern Spain), while the sea water scenario is based on literature data. Four impact categories and two environmental indicators, one of them related to brine discharge, are included. The results show that the key life-cycle issue of brackish groundwater desalination is electricity consumption, and since this is substantially reduced with regard to using sea water, the life-cycle impacts are found to be almost 50% lower. An uncertainty analysis based on Monte-Carlo simulation shows that these environmental savings are significant for all impact categories. Potential local impacts provoked by brine discharge are also found to be lower, due to a reduced content of salts. It is concluded that, when and wherever possible, exploitation of brackish groundwater resources should be assigned priority to sea water resources as an input for reverse osmosis desalination, although it must be taken into account that groundwater, as opposed to sea water, is a limited resource.

  14. Hydro-environmental management of groundwater resources: A fuzzy-based multi-objective compromise approach

    Science.gov (United States)

    Alizadeh, Mohammad Reza; Nikoo, Mohammad Reza; Rakhshandehroo, Gholam Reza

    2017-08-01

    Sustainable management of water resources necessitates close attention to social, economic and environmental aspects such as water quality and quantity concerns and potential conflicts. This study presents a new fuzzy-based multi-objective compromise methodology to determine the socio-optimal and sustainable policies for hydro-environmental management of groundwater resources, which simultaneously considers the conflicts and negotiation of involved stakeholders, uncertainties in decision makers' preferences, existing uncertainties in the groundwater parameters and groundwater quality and quantity issues. The fuzzy multi-objective simulation-optimization model is developed based on qualitative and quantitative groundwater simulation model (MODFLOW and MT3D), multi-objective optimization model (NSGA-II), Monte Carlo analysis and Fuzzy Transformation Method (FTM). Best compromise solutions (best management policies) on trade-off curves are determined using four different Fuzzy Social Choice (FSC) methods. Finally, a unanimity fallback bargaining method is utilized to suggest the most preferred FSC method. Kavar-Maharloo aquifer system in Fars, Iran, as a typical multi-stakeholder multi-objective real-world problem is considered to verify the proposed methodology. Results showed an effective performance of the framework for determining the most sustainable allocation policy in groundwater resource management.

  15. Management of Egypt's Surface and Groundwater Resources: Present and Future

    Science.gov (United States)

    Sultan, M.; Ahmed, M.; Yan, E.; Milewski, A.; Mohamed, L.; Farag, A. Z. A.

    2014-12-01

    The River Nile is the main source of fresh water in Egypt. Most of Egypt's River Nile water (>85%) originates as precipitation over the Ethiopian highlands and is channeled by the Blue Nile. The construction (years: 2011 to 2017) of the Renaissance Dam (reservoir capacity: 70 x 109m3) on the Blue Nile poses an extreme threat to Egypt's population. If the reservoir was to be filled in 7 years, Egypt will lose (during each of 7 years following dam completion) a minimum of 15 x 109m3 of its annual allocation (55 x 109m3) to reservoir filling (10 x 109m3), evaporation (3.5 x 109m3), and infiltration (1.5 x 109m3). Three solutions are proposed: Solution I takes advantage of the cyclicity of Nile floods and is based on findings from a calibrated (against temporal head data) unconfined 2-dimensional transient groundwater flow model for Lake Nasser and surroundings and a calibrated (against lake levels) surface water model. Models show with time: (1) losses to infiltration will decrease (1975-193: 58.4 109m3; 1993-2001: 43.6 x 109m3) due to silting of Lake bottom and encroachment of excess Lake Nasser water will increase (e.g., 1975-1993: none; 1993-2001: 17 x 109m3). We propose to develop sustainable agricultural in the Western Desert: (1) In high flood years, excess Lake Nasser water (e.g., 1993-2001: 17 x 109m3) is channeled across the plateau bounding (from west) the River Nile valley to artificially recharge the Nubian Sandstone Aquifer System (NSAS) that crops out west of the plateau and, (2) in low flood years, we extract the recharged groundwater. Solution II calls on mining the NSAS at reasonable rates. Using temporal (January 2003 - September 2012) Gravity Recovery and Climate Experiment (GRACE) data we estimate the annual depletion rates at 2 x 109m3 due to artificial extraction (1.5 x 109m3) and natural discharge (0.5 x 109m3). Assuming current GRACE depletion rates, the recoverable groundwater (5,180 x 109m3) will last for 2500 years; if we were to quadruple

  16. Geophysical and geochemical characterisation of groundwater resources in Western Zambia

    DEFF Research Database (Denmark)

    Chongo, Mkhuzo; Banda, Kawawa Eddy; Bauer-Gottwein, Peter

    both ground-based and airborne geophysical methods as well as extensive water quality sampling. The occurrence of saline groundwater follows a clear spatial pattern and appears to be related to the palaeo Lake Makgadikgadi, whose northernmost extension reached into the Machile area. Because the lake...... precipitation has formed limited freshwater reservoirs in a generally saline area, which need to be sustainably managed. We will present initial results from the geophysical and geochemical surveys conducted over the past few years. We will interpret these findings in terms of the geologic history of Southern...

  17. Sustainable Management of Groundwater Resources: A Case Study from the North China Plain

    Science.gov (United States)

    Liu, J.; Zheng, C.; Zheng, L.; Wu, J.; Lei, Y.

    2005-12-01

    With the dramatic increase of population and rapid growth of municipal and industrial water demands, global water shortage is becoming more and more acute. One of the most striking examples for groundwater depletion is the North China Plain (NCP). As the most important center of agricultural production and home to more than 200 million people in China, NCP is experiencing a rapid depletion of its groundwater resources. Groundwater levels in many parts of NCP are currently declining at a rate of 1 m/year or even more due to excessive pumping. A numerical groundwater flow model was developed in this study for the Shijiazhuang region, a typical part of NCP where groundwater is the main water supply source for local agriculture irrigation and municipal and industrial water needs. The model indicated unsustainable groundwater utilization as the pumping exceeds recharge by a large amount. In this study, management optimization modeling was conducted to quantify and improve the sustainability of groundwater utilization in the study area. Based on the calibrated flow model, an optimization formulation was first set up to identify the optimal pumping well locations and rates that lead to the maximum total yield subject to a series of water level constraints. A second optimization formulation was then considered to minimize the total management costs required to meet the projected total water demands, also subject to the same set of water level constraints. The optimization models in this study provide a useful tool for developing cost-effective strategies for sustainable management of groundwater resources on the NCP. The findings from this study are of potentially wide interest to other parts of the world under similar hydrogeological and economic conditions.

  18. Impacts of land use changes on groundwater resources in the Heihe River Basin%黑河流域土地利用变化对地下水资源的影响

    Institute of Scientific and Technical Information of China (English)

    王根绪; 杨玲媛; 陈玲

    2005-01-01

    Land use and land cover changes have a great impact on the regional hydrological process.Based on three periods of remote sensing data from the 1960s and the long-term observed data of groundwater from the 1980s, the impacts of land use changes on the groundwater system in the middle reach of Heihe River Basin in recent three decades are analyzed by the perspective of groundwater recharge and discharge system. The results indicate that with the different intensities of land use changes, the impacts on the groundwater recharge were 2.602 × 108 m3/a in the former 15 years (1969-1985) and 0.218 ×108 m3/a in the latter 15 years (1986-2000), and the impacts on the groundwater discharge were 2.035 × 108 m3/a and 4.91 × 108 m3/a respectively. When the groundwater exploitation was in a reasonable range less than 3.0 × 108 m3/a, the land use changes could control the changes of regional groundwater resources. Influenced by the land use changes and the large-scale exploitation in the recent decade, the groundwater resources present apparently regional differences in Zhangye region. Realizing the impact of land use changes on groundwater system and the characteristics of spatial-temporal variations of regional groundwater resources would be very important for reasonably utilizing and managing water and soil resources.

  19. Evaluation of the impact of fuel hydrocarbons and oxygenates on groundwater resources.

    Science.gov (United States)

    Shih, Tom; Rong, Yue; Harmon, Thomas; Suffet, Mel

    2004-01-01

    The environmental behavior of fuel oxygenates (other than methyl tert-butyl ether [MTBE]) is poorly understood because few data have been systematically collected and analyzed. This study evaluated the potential for groundwater resource contamination by fuel hydrocarbons (FHCs) and oxygenates (e.g., tert-butyl alcohol [TBA], tertamyl methyl ether [TAME], diisopropyl ether [DIPE], ethyl tert-butyl ether [ETBE], and MTBE) by examining their occurrence, distribution, and spatial extent in groundwater beneath leaking underground fuel tank (LUFT) facilities, focusing on data collected from over 7200 monitoring wells in 868 LUFT sites from the greater Los Angeles, CA, region. Excluding the composite measure total petroleum hydrocarbons as gasoline (TPHG), TBA has the greatestsite maximum (geometric mean) groundwater concentration among the study analytes; therefore, its presence needs to be confirmed at LUFT sites so that specific cleanup strategies can be developed. The alternative ether oxygenates (DIPE, TAME, and ETBE) are less likely to be detected in groundwater beneath LUFT facilities in the area of California studied and when detected are present at lower dissolved concentrations than MTBE, benzene, or TBA. Groundwater plume length was used as an initial indicator of the threat of contamination to drinking water resources. Approximately 500 LUFT sites were randomly selected and analyzed. The results demonstrate MTBE to pose the greatest problem, followed by TBA and benzene. The alternative ether oxygenates were relatively localized and indicated lesser potential for groundwater resource contamination. However, all indications suggest the alternative ether oxygenates would pose groundwater contamination threats similar to MTBE if their scale of usage is expanded. Plume length data suggest that in the absence of a completely new design and construction of the underground storage tank (UST) system, an effective management strategy may involve placing greater emphasis

  20. Regional Analysis of the Effects of Oil and Gas Development on Groundwater Resources in California

    Science.gov (United States)

    Landon, M. K.; McMahon, P. B.; Kulongoski, J. T.; Ball, L. B.; Gillespie, J. M.; Shimabukuro, D.; Taylor, K. A.

    2016-12-01

    The California State Water Resources Control Board is collaborating with the U.S. Geological Survey to implement a Regional Monitoring Program (RMP) to assess potential interactions between oil/gas stimulation treatment and groundwater resources. The effects of stimulation on groundwater resources will be difficult to distinguish from the effects of other past or present components of oil and gas development. As a result, the RMP is designed to provide an overall assessment of the effects of oil and gas development on groundwater quality. During 2016-17, the study is focused on selected priority oilfields in the eastern and western portions of the San Joaquin Valley in Kern County to: (1) produce three-dimensional (3D) salinity maps, (2) characterize the chemical composition of groundwater and produced water, and (3) identify the extent to which fluids from oil and gas development may be moving into protected (total dissolved solids less than 10,000 milligrams per liter) groundwater at regional scales. Analysis of available salinity data near oil/gas fields indicates there are regional patterns to salinity depth profiles; however, data gaps between the depths of water and oil/gas wells are common. These results provide a foundation for more detailed oilfield-scale salinity mapping, which includes geophysical methods (borehole, surface, and airborne) to fill data gaps. The RMP sampling-well networks are designed to evaluate groundwater quality along transects from oil/gas fields into adjacent aquifers and consist of existing wells supplemented by monitoring-well installation in priority locations identified by using 3D visualization of hydrogeologic data. The analytes include constituents with different transport characteristics such as dissolved gases, inorganic components (brines), and petroleum compounds. Analytes were selected because of their potential usefulness for understanding processes and pathways by which fluids from oilfield sources reach groundwater.

  1. Selection of spatial scale for assessing impacts of groundwater-based water supply on freshwater resources

    DEFF Research Database (Denmark)

    Hybel, Anne-Marie; Godskesen, Berit; Rygaard, Martin

    2015-01-01

    the highest uncertainty, as it requires estimations of non-measurable environmental water requirements. Hence, the development of a methodology to obtain more site-specific and relevant estimations of environmental water requirements should be prioritized. Finally, the demarcation of the groundwater resource......Indicators of the impact on freshwater resources are becoming increasingly important in the evaluation of urban water systems. To reveal the importance of spatial resolution, we investigated how the choice of catchment scale influenced the freshwater impact assessment. Two different indicators were...... used in this study: the Withdrawal-To-Availability ratio (WTA) and the Water Stress Index (WSI). Results were calculated for three groundwater based Danish urban water supplies (Esbjerg, Aarhus, and Copenhagen). The assessment was carried out at three spatial levels: (1) the groundwater body level, (2...

  2. Groundwater dynamics in the Amazon basin from remotely sensed observations and hydrological models

    Science.gov (United States)

    Frappart, Frédéric; Papa, Fabrice; Tomasella, Javier; Ramillien, Guillaume; Güntner, Andreas; Emilio, Thaise; Schietti, Juliana; da Silva Carvalho, João

    2014-05-01

    Groundwater plays a key role in the terrestrial hydrological cycle and the water balance on the continents. It accounts for more than 30% (i.e., 8,000,000 km3 to 10,000,000 km3) of global fresh-water resources, and is also the major resource of water supply for 40% of the world's population and 50% of the world's food production. However, groundwater storage and its variations are still poorly known at global scale due to the limited extent of current monitoring networks. Most of the studies on geohydrology in the Amazon basin were carried out at local scale except a recent study that pointed out evidences on regional scale groundwater flows using a geothermal method. Gravimetry from space offers the unique opportunity to monitor water resources at basin to continental scales. The Gravity Recovery And Climate Experiment (GRACE) mission, launched in 2002, detects tiny changes in the Earth's gravity field which can be related to spatio-temporal variations of TWS at monthly or sub-monthly time-scales. Variations in groundwater storage (GW) can be separated from the TWS anomalies measured by GRACE using external information on the other hydrological reservoirs such as in situ observations, model outputs, or both. Very few studies have been undertaken yet in large river basins characterized by extensive wetlands and floodplains, due to the lack of reliable and timely information about the extent, spatial distribution, as well as the amount of water stored in wetlands and floods and their temporal variations. Using multi-satellite observations for surface water storage (SW) and hydrological outputs for soil moisture (SM), variations in GW were estimated in the Negro basin, the second largest tributary of the Amazon in terms of discharge. Here, the same approach was applied in the whole Amazon basin, allowing to estimate the contribution of each hydrological reservoir to TWS, to monitor its time variations, and to map the annual changes in the aquifers over 2003

  3. Groundwater Recharge Estimation using Low-Cost Observation Techniques and Potential Applications

    Science.gov (United States)

    Holländer, Hartmut; Wang, Zijian; Assefa, Kibreab; Woodbury, Allan

    2016-04-01

    Sustainable groundwater management requests groundwater recharge estimation as a critical quantity. We used physical-based modelling using data from a low-cost weather station and tested the feasibility and robustness of recharge estimation. The method was tested on two locations in British Columbia (B.C.), Canada. The main study was conducted in Southern Abbotsford, B.C. and applications related to water management in future climates and to water usage optimization were conducted in Okanagan Valley, B.C. Recharge was determined using HYDRUS-1D. The meteorological data were recorded by a HOBO weather station for a short observation period (about 1 year) and an existing weather station (Abbotsford A) for long-term study purpose (27 years). The derived soil hydraulic parameters of two undisturbed soil cores were used to characterize the soil. Model performance was evaluated by using observed soil moisture and soil temperature data. A rigorous sensitivity analysis was used to test the robustness of the model. Recharge during the short observation period was estimated at 863 mm and 816 mm. The mean annual recharge was estimated at 848 mm/year, and 859 mm/year based on a time series of 27 years. 80% of precipitation contributed to recharge in hydrologic winter period. The comparison of the recharge estimates with other studies indicates a good agreement. Being able to predict transient recharge estimates, this method can provide a tool for estimates on nutrient leaching which is often controlled by strong precipitation events and rapid infiltration of water and nitrate into the soil. Modeling supports that recharge estimates at high temporal resolution also increase the prediction quality of nitrate leaching. The application for water resources related problems in the Okanagan Valley showed that linking groundwater and surface water using regional groundwater estimates improved calibration of existing groundwater model strongly and that our method is capable to use

  4. Investigation of Pb, Cd, Cu and Mg Concentrations in Groundwater Resources of Razan Plain

    Directory of Open Access Journals (Sweden)

    S. Sobhan Ardakani

    2015-01-01

    Full Text Available Introduction & Objective: Iran is located in the dry and semi dry regions, thus almost 90% of the required fresh water is exploited from groundwater resources. Due to the increasing pol-lution of water resources, the purpose of this study was evaluation of Pb, Cd, Cu and Mg concentrations in groundwater resources of Razan Plain and preparing the zoning map using GIS. Materials & Methods: Groundwater samples were collected from 20 selected stations during two seasons in 2012. The samples were filtered (0.45 ?m and maintained cool in polyethyl-ene bottles. The samples were taken for the analysis of cations, the former was acidified with HNO3 to pH lower than 2. Minor elements were determined using ICP-OES. All statistical analyses were performed using the SPSS statistical package. Also, Kriging Method was used to prepare spatial distribution maps of elements in groundwater samples. Results: The results showed that the mean concentrations of Pb, Cd, Cu and Mg in the groundwater samples during the spring were 5.60±0.66, 0.21±0.04, 32.10±2.21 and 6990.0±302.10 ppb, respectively, and the mean concentrations of these elements in the groundwater samples in the summer were 4.86±0.46, 0.30±0.08, 25.55±3.63 and 3654.05±215.65 ppb, respectively. Comparing the mean concentrations of the evaluated metals with WHO permissible limits showed a significant difference (p<0.05. Thus, the mean concentrations of the metals were significantly lower than the permissible limits. Conclusion: Although the groundwater resources of Razan Plain are not currently polluted with heavy metals, long-term excessive use of agricultural inputs and establishment of pollut-ing industries, can pose a threat to groundwater resources of this area. (Sci J Hamadan Univ Med Sci 2015; 21(4:319-329

  5. Climate change impact on freshwater resources in a deltaic environment: A groundwater modeling study

    Science.gov (United States)

    Matiatos, Ioannis; Alexopoulos, John D.; Panagopoulos, Andreas; Nastos, Panagiotis T.; Kotsopoulos, Spyros; Ghionis, George; Poulos, Serafim

    2016-04-01

    Climate change is expected to affect the hydrological cycle, altering seawater level and groundwater recharge to coastal aquifers with various other associated impacts on natural ecosystems and human activities. As the sustainable use of groundwater resources is a great challenge for many countries in the world, groundwater modeling has become a very useful and well established tool for studying groundwater management problems. This study investigates the impacts of climate change on the groundwater of the deltaic plain of River Pinios (Central Greece). Geophysical data processing indicates that the phreatic aquifer extends mainly in the central and northern parts of the region. A one-layer transient groundwater flow and contaminant mass transport model of the aquifer system is calibrated and validated. Impacts of climate change were evaluated by incorporating the estimated recharge input and sea level change of different future scenarios within the simulation models. The most noticeable and consistent result of the climate change impact simulations is a prominent sea water intrusion in the coastal aquifer mainly as a result of sea level change which underlines the need for a more effective planning of environmental measures.

  6. Ecology-oriented groundwater resource assessment in the Tuwei River watershed, Shaanxi Province, China

    Science.gov (United States)

    Yang, Z. Y.; Wang, W. K.; Wang, Z.; Jiang, G. H.; Li, W. L.

    2016-08-01

    In arid and semi-arid regions, a close relationship exists between groundwater and supergene eco-environmental issues such as swampiness, soil salinization, desertification, vegetation degradation, reduction of stream base flow, and disappearance of lakes and wetlands. When the maximum allowable withdrawal of groundwater (AWG) is assessed, an ecology-oriented regional groundwater resource assessment (RGRA) method should be used. In this study, a hierarchical assessment index system of the supergene eco-environment was established based on field survey data and analysis of the supergene eco-environment factors influenced by groundwater in the Tuwei River watershed, Shaanxi Province, China. The assessment system comprised 11 indices, including geomorphological type, lithology and structure of the vadose zone, depth of the water table (DWT), total dissolved solids content of groundwater, etc. Weights for all indices were calculated using an analytical hierarchy process. Then, the current eco-environmental conditions were assessed using fuzzy comprehensive evaluation (FCE). Under the imposed constraints, and using both the assessment results on the current eco-environment situation and the ecological constraint of DWT (1.5-5.0 m), the maximum AWG (0.408 × 108 m3/a or 24.29 % of the river base flow) was determined. This was achieved by combining the groundwater resource assessment with the supergene eco-environmental assessment based on FCE. If the maximum AWG is exceeded in a watershed, the eco-environment will gradually deteriorate and produce negative environmental effects. The ecology-oriented maximum AWG can be determined by the ecology-oriented RGRA method, and thus sustainable groundwater use in similar watersheds in other arid and semi-arid regions can be achieved.

  7. Ecology-oriented groundwater resource assessment in the Tuwei River watershed, Shaanxi Province, China

    Science.gov (United States)

    Yang, Z. Y.; Wang, W. K.; Wang, Z.; Jiang, G. H.; Li, W. L.

    2016-12-01

    In arid and semi-arid regions, a close relationship exists between groundwater and supergene eco-environmental issues such as swampiness, soil salinization, desertification, vegetation degradation, reduction of stream base flow, and disappearance of lakes and wetlands. When the maximum allowable withdrawal of groundwater (AWG) is assessed, an ecology-oriented regional groundwater resource assessment (RGRA) method should be used. In this study, a hierarchical assessment index system of the supergene eco-environment was established based on field survey data and analysis of the supergene eco-environment factors influenced by groundwater in the Tuwei River watershed, Shaanxi Province, China. The assessment system comprised 11 indices, including geomorphological type, lithology and structure of the vadose zone, depth of the water table (DWT), total dissolved solids content of groundwater, etc. Weights for all indices were calculated using an analytical hierarchy process. Then, the current eco-environmental conditions were assessed using fuzzy comprehensive evaluation (FCE). Under the imposed constraints, and using both the assessment results on the current eco-environment situation and the ecological constraint of DWT (1.5-5.0 m), the maximum AWG (0.408 × 108 m3/a or 24.29 % of the river base flow) was determined. This was achieved by combining the groundwater resource assessment with the supergene eco-environmental assessment based on FCE. If the maximum AWG is exceeded in a watershed, the eco-environment will gradually deteriorate and produce negative environmental effects. The ecology-oriented maximum AWG can be determined by the ecology-oriented RGRA method, and thus sustainable groundwater use in similar watersheds in other arid and semi-arid regions can be achieved.

  8. Evaluating the impact of climate change on groundwater resources in a small Mediterranean watershed.

    Science.gov (United States)

    Ertürk, Ali; Ekdal, Alpaslan; Gürel, Melike; Karakaya, Nusret; Guzel, Cigdem; Gönenç, Ethem

    2014-11-15

    Western Mediterranean Region of Turkey is subject to considerable impacts of climate change that may adversely affect the water resources. Decrease in annual precipitation and winter precipitation as well as increase in temperatures are observed since 1960s. In this study, the impact of climate change on groundwater resources in part of Köyceğiz-Dalyan Watershed was evaluated. Evaluation was done by quantifying the impacts of climate change on the water budget components. Hydrological modeling was conducted with SWAT model which was calibrated and validated successfully. Climate change and land use scenarios were used to calculate the present and future climate change impacts on water budgets. According to the simulation results, almost all water budget components have decreased. SWAT was able to allocate less irrigation water because of the decrease of overall water due to the climate change. This resulted in an increase of water stressed days and temperature stressed days whereas crop yields have decreased according to the simulation results. The results indicated that lack of water is expected to be a problem in the future. In this manner, investigations on switching to more efficient irrigation methods and to crops with less water consumption are recommended as adaptation measures to climate change impacts.

  9. Groundwater resources in the State of São Paulo (Brazil: the application of indicators

    Directory of Open Access Journals (Sweden)

    Ricardo Hirata

    2007-03-01

    Full Text Available Indicators, for groundwater resources, have mostly been employed to define the present status and the degradation tendency, regarding both quantity (under- or overexploitation and quality (natural and anthropic contamination. This work presents the application of indicators in order to draw a picture of the groundwater resources situation in the 22 Water Resource Management Units (WRMU of the State of São Paulo. The seven Indicators (I1 to I7 applied provide a general overview of groundwater dependence (I1, I2, availability (I3, I4, and quality (I5, I6, I7. Considering public supply (Indicator 1, one observes that 9 WRMUs show high (>50% of the population supplied by groundwater, 6, intermediate (49-25%, and 7, low (Indicadores, para recursos hídricos subterrâneos, têm sido utilizados principalmente para a avaliação da situação atual e tendência de degradação, com relação tanto à quantidade (sub- ou super-exploração como à qualidade (contaminações natural e antrópica. Neste sentido, este trabalho apresenta a aplicação de indicadores com o objetivo de obter um quadro geral da situação dos recursos hídricos nas 22 Unidades de Gerenciamento de Recursos Hídricos (UGRHI do Estado de São Paulo. Foram aplicados 7 indicadores (I1 a I7 com o objetivo de fornecer uma visão geral com relação à dependência (I1 e I2, disponibilidade (I3 e I4, e qualidade (I5, I6 e I7 da água subterrânea. No que se refere ao abastecimento público (indicador 1, 9 UGRHIs apresentam alta ( > 50% da população é suprida por água subterrânea, 6, intermediária (49 a 25% e 7, baixa ( < 24% dependência do recurso hídrico subterrâneo. Os indicadores 3 e 4 mostram que o recurso ainda apresenta grande potencial para explotações adicionais na maioria das UGRHIs, no entanto há evidências de superexploração nas bacias do Alto Tietê, Turvo/Grande e Pardo e baixa disponibilidade nas bacias do Alto Tietê, Piracicaba/Capivari/Jundiaí, e Turvo

  10. Geology and ground-water resources of Washington County, Colorado

    Science.gov (United States)

    McGovern, Harold E.

    1964-01-01

    to the thickness of saturated material. Development of ground water for irrigation has been generally restricted to the South Platte, Arikaree, and Beaver valleys. There were 134 irrigation wells, 3 industrial wells, and 10 municipal wells in the county in 1959. The annual ground-water pumpage from Washington County is estimated to be 18,000 acre-ft; about 10,000 acre-ft is from the High Plains ground-water province. Although some ground water enters the county as underflow, most of the recharge to ground-water reservoirs is from precipitation on the land surface. Recharge to the Ogallala Formation in the county is assumed to be approximately equal to the natural discharge from the county by underflow because ground-water withdrawals are from storage, and no other significant amount of natural discharge is apparent. Undertow in the Ogallala was calculated to be 83,000 acre-ft per year and the rate of recharge from precipitation to be about 0.95 inch per year. Neither recharge nor discharge was calculated for that part of the county in the South Platte River basin. All ground water in Washington County has a high proportion of carbonate and is classed as hard to very hard. The sodium-adsorption-ratio for all samples analyzed was below the limit recommended for irrigation water. All the water from the Ogallala Formation and most of the water from the Chadron Formation is suitable for domestic use. Some water from the alluvial deposits overlying the Pierre Shale was exceptionally high in calcium, magnesium, and sodium sulfates. Ground water has been heavily developed for irrigation in the South Platte valley and in some parts of the Beaver and Arikaree valleys. Some additional areas, however, could be developed in the latter two valleys. Large quantities of ground water in the Ogallala Formation are available for future development. The quantity of water in storage in the High Plains ground-water province in Washington County is about 6.5 million acre-f

  11. Impact of water allocation strategies to manage groundwater resources in Western Australia: Equity and efficiency considerations

    Science.gov (United States)

    Iftekhar, Md Sayed; Fogarty, James

    2017-05-01

    In many parts of the world groundwater is being depleting at an alarming rate. Where groundwater extraction is licenced, regulators often respond to resource depletion by reducing all individual licences by a fixed proportion. This approach can be effective in achieving a reduction in the volume of water extracted, but the approach is not efficient. In water resource management the issue of the equity-efficiency trade-off has been explored in a number of contexts, but not in the context of allocation from a groundwater system. To contribute to this knowledge gap we conduct an empirical case study for Western Australia's most important groundwater system: the Gnangara Groundwater System (GGS). Resource depletion is a serious issue for the GGS, and substantial reductions in groundwater extraction are required to stabilise the system. Using an individual-based farm optimization model we study both the overall impact and the distributional impact of a fixed percentage water allocation cut to horticulture sector licence holders. The model is parameterised using water licence specific data on farm area and water allocation. The modelling shows that much of the impact of water allocation reductions can be mitigated through changing the cropping mix and the irrigation technology used. The modelling also shows that the scope for gains through the aggregation of holdings into larger farms is much greater than the potential losses due to water allocation reductions. The impact of water allocation cuts is also shown to impact large farms more than small farms. For example, the expected loss in net revenue per ha for a 10-ha farm is around three times the expected loss per ha for a 1-ha farm; and the expected loss per ha for a 25-ha farm is around five times the expected loss per ha for a 1-ha farm.

  12. Groundwater resource-directed measures software | Dennis | Water ...

    African Journals Online (AJOL)

    ... the need to promote social and economic development through the use of water, ... To be able to implement the National Water Act (NWA), the Minister needs to ... in resource quality objectives which are based on both the classification and ...

  13. A Feasibility Analysis of Land-Based SINS/GNSS Gravimetry for Groundwater Resource Detection in Taiwan

    Directory of Open Access Journals (Sweden)

    Kai-Wei Chiang

    2015-09-01

    Full Text Available The integration of the Strapdown Inertial Navigation System and Global Navigation Satellite System (SINS/GNSS has been implemented for land-based gravimetry and has been proven to perform well in estimating gravity. Based on the mGal-level gravimetry results, this research aims to construct and develop a land-based SINS/GNSS gravimetry device containing a navigation-grade Inertial Measurement Unit. This research also presents a feasibility analysis for groundwater resource detection. A preliminary comparison of the kinematic velocities and accelerations using multi-combination of GNSS data including Global Positioning System, Global Navigation Satellite System, and BeiDou Navigation Satellite System, indicates that three-system observations performed better than two-system data in the computation. A comparison of gravity derived from SINS/GNSS and measured using a relative gravimeter also shows that both agree reasonably well with a mean difference of 2.30 mGal. The mean difference between repeat measurements of gravity disturbance using SINS/GNSS is 2.46 mGal with a standard deviation of 1.32 mGal. The gravity variation because of the groundwater at Pingtung Plain, Taiwan could reach 2.72 mGal. Hence, the developed land-based SINS/GNSS gravimetry can sufficiently and effectively detect groundwater resources.

  14. A Feasibility Analysis of Land-Based SINS/GNSS Gravimetry for Groundwater Resource Detection in Taiwan.

    Science.gov (United States)

    Chiang, Kai-Wei; Lin, Cheng-An; Kuo, Chung-Yen

    2015-09-29

    The integration of the Strapdown Inertial Navigation System and Global Navigation Satellite System (SINS/GNSS) has been implemented for land-based gravimetry and has been proven to perform well in estimating gravity. Based on the mGal-level gravimetry results, this research aims to construct and develop a land-based SINS/GNSS gravimetry device containing a navigation-grade Inertial Measurement Unit. This research also presents a feasibility analysis for groundwater resource detection. A preliminary comparison of the kinematic velocities and accelerations using multi-combination of GNSS data including Global Positioning System, Global Navigation Satellite System, and BeiDou Navigation Satellite System, indicates that three-system observations performed better than two-system data in the computation. A comparison of gravity derived from SINS/GNSS and measured using a relative gravimeter also shows that both agree reasonably well with a mean difference of 2.30 mGal. The mean difference between repeat measurements of gravity disturbance using SINS/GNSS is 2.46 mGal with a standard deviation of 1.32 mGal. The gravity variation because of the groundwater at Pingtung Plain, Taiwan could reach 2.72 mGal. Hence, the developed land-based SINS/GNSS gravimetry can sufficiently and effectively detect groundwater resources.

  15. Optimizing conjunctive use of surface water and groundwater resources with stochastic dynamic programming

    Science.gov (United States)

    Davidsen, Claus; Liu, Suxia; Mo, Xingguo; Rosbjerg, Dan; Bauer-Gottwein, Peter

    2014-05-01

    Optimal management of conjunctive use of surface water and groundwater has been attempted with different algorithms in the literature. In this study, a hydro-economic modelling approach to optimize conjunctive use of scarce surface water and groundwater resources under uncertainty is presented. A stochastic dynamic programming (SDP) approach is used to minimize the basin-wide total costs arising from water allocations and water curtailments. Dynamic allocation problems with inclusion of groundwater resources proved to be more complex to solve with SDP than pure surface water allocation problems due to head-dependent pumping costs. These dynamic pumping costs strongly affect the total costs and can lead to non-convexity of the future cost function. The water user groups (agriculture, industry, domestic) are characterized by inelastic demands and fixed water allocation and water supply curtailment costs. As in traditional SDP approaches, one step-ahead sub-problems are solved to find the optimal management at any time knowing the inflow scenario and reservoir/aquifer storage levels. These non-linear sub-problems are solved using a genetic algorithm (GA) that minimizes the sum of the immediate and future costs for given surface water reservoir and groundwater aquifer end storages. The immediate cost is found by solving a simple linear allocation sub-problem, and the future costs are assessed by interpolation in the total cost matrix from the following time step. Total costs for all stages, reservoir states, and inflow scenarios are used as future costs to drive a forward moving simulation under uncertain water availability. The use of a GA to solve the sub-problems is computationally more costly than a traditional SDP approach with linearly interpolated future costs. However, in a two-reservoir system the future cost function would have to be represented by a set of planes, and strict convexity in both the surface water and groundwater dimension cannot be maintained

  16. Implication of Groundwater Resources Utilization in Mountainous Region for Slopeland Disaster Prevention

    Science.gov (United States)

    Huang, Chi-Chao; Hsu, Shih-Meng; Lo, Hung-Chieh

    2016-04-01

    In recent years, groundwater resources from mountainous regions have been considered as an alternative water resource in Taiwan. According to previous research outcomes (Hsu, 2011), such a groundwater resource is capable of providing stable and high quality water resources. Additionally, another advantage of using the water resources is attributed to the contribution of slopeland disaster prevention. While pumping groundwater as water resources in hilly areas (e.g., at landslide-prone sites), pore-water pressures can be dropped, which can result in stabilizing landslide-prone slopes. However, the benefit to slope stability by using groundwater resources needs to be quantified. The purpose of this study is to investigate groundwater potential of a deep-seated landslide site first, and then to evaluate variations of slope stability by changing well pumping rate conditions. In this paper, the Baolong landslide site located at the Jiasian district of Kaohsiung city in Southern Taiwan has been selected as a case study. Hydrogeological investigation for the landslide site was conducted to clarify the complexity of field characteristics and to establish a precise conceptual model for simulation. The investigation content includes surficial geology investigation, borehole drilling (6 drilling boreholes and 350 meters drilling length in total), 45 m pumping well construction, borehole hydrogeological tests (borehole televiewer, caliper, borehole electrical logging, sonic logging, flowmeter measurement, pumping test, and double packer test), and laboratory tests from rock core samples (physical properties test of soil and rocks, triaxial permeability test of soil, porosity determination test using helium, and gas permeability test). Based on the aforementioned investigation results, a hydrogeological conceptual model for the Baolong landslide site was constructed, and a 2D slope stability model coupled with transient seepage flow model was used for numerical simulation to

  17. Characterization of saline groundwater across the coastal aquifer of Israel as resource for desalination

    Science.gov (United States)

    Stein, Shaked; Russak, Amos; Sivan, Orit; Yechieli, Yospeh; Oren, Yoram; Kasher, Roni

    2015-04-01

    compared. The results have shown that using saline groundwater underneath the FSI as a resource for RO desalination process is beneficial in terms of fluxes: the flux reduction in the seawater desalination was 16% of the initial flux, while the flux reduction with the saline groundwater was only 9%. The SDI and total organic carbon were lower in saline groundwater than in seawater, which support the flux results. Therefore, using saline groundwater as feed water for desalination may be advantageous because of lower operational costs and reduced applied pressure needed and energy usage.

  18. Optimal integrated management of groundwater resources and irrigated agriculture in arid coastal regions

    Science.gov (United States)

    Grundmann, J.; Schütze, N.; Heck, V.

    2014-09-01

    Groundwater systems in arid coastal regions are particularly at risk due to limited potential for groundwater replenishment and increasing water demand, caused by a continuously growing population. For ensuring a sustainable management of those regions, we developed a new simulation-based integrated water management system. The management system unites process modelling with artificial intelligence tools and evolutionary optimisation techniques for managing both water quality and water quantity of a strongly coupled groundwater-agriculture system. Due to the large number of decision variables, a decomposition approach is applied to separate the original large optimisation problem into smaller, independent optimisation problems which finally allow for faster and more reliable solutions. It consists of an analytical inner optimisation loop to achieve a most profitable agricultural production for a given amount of water and an outer simulation-based optimisation loop to find the optimal groundwater abstraction pattern. Thereby, the behaviour of farms is described by crop-water-production functions and the aquifer response, including the seawater interface, is simulated by an artificial neural network. The methodology is applied exemplarily for the south Batinah re-gion/Oman, which is affected by saltwater intrusion into a coastal aquifer system due to excessive groundwater withdrawal for irrigated agriculture. Due to contradicting objectives like profit-oriented agriculture vs aquifer sustainability, a multi-objective optimisation is performed which can provide sustainable solutions for water and agricultural management over long-term periods at farm and regional scales in respect of water resources, environment, and socio-economic development.

  19. Estimating the Impact of Drought on Groundwater Resources of the Marshall Islands

    Directory of Open Access Journals (Sweden)

    Brandon L. Barkey

    2017-01-01

    Full Text Available Groundwater resources of small coral islands are threatened due to short-term and long-term changes in climate. A significant short-term threat is El Niño events, which typically induce a severe months-long drought for many atoll nations in the western and central Pacific regions that exhausts rainwater supply and necessitates the use of groundwater. This study quantifies fresh groundwater resources under both average rainfall and drought conditions for the Republic of Marshall Islands (RMI, a nation composed solely of atolls and which is severely impacted by El Niño droughts. The atoll island algebraic model is used to estimate the thickness of the freshwater lens for 680 inhabited and uninhabited islands of the RMI, with a focus on the severe 1998 drought. The model accounts for precipitation, island width, hydraulic conductivity of the upper Holocene-age sand aquifer, the depth to the contact between the Holocene aquifer and the lower Pleistocene-age limestone aquifer, and the presence of a reef flat plate underlying the ocean side of the island. Model results are tested for islands that have fresh groundwater data. Results highlight the fragility of groundwater resources for the nation. Average lens thickness during typical seasonal rainfall is approximately 4 m, with only 30% of the islands maintaining a lens thicker than 4.5% and 55% of the islands with a lens less than 2.5 m thick. Thicker lenses typically occur for larger islands, islands located on the leeward side of an atoll due to lower hydraulic conductivity, and islands located in the southern region of the RMI due to higher rainfall rates. During drought, groundwater on small islands (<300 m in width is completely depleted. Over half (54% of the islands are classified as “Highly Vulnerable” to drought. Results provide valuable information for RMI water resources planners, particularly during the current 2016 El Niño drought, and similar methods can be used to quantify

  20. Water Quality Pollution Indices to Assess the Heavy Metal Contamination, Case Study: Groundwater Resources of Asadabad Plain In 2012

    Directory of Open Access Journals (Sweden)

    Soheil Sobhan Ardakani

    2016-09-01

    Full Text Available Background & Aims of the Study: Due to the increasing pollution of water resources, tow documented methods: the Heavy metal potential index (HPI and the Heavy metal evaluation index (HEI were evaluated for their suitability for contamination monitoring of heavy metals (As, Zn, Pb, Cd and Cu contamination in groundwater resources of Asadabad Plain during spring and summer in 2012. Materials & Methods: In this analytical observational study, concentrations of heavy metals have been evaluated at 30 important groundwater sampling stations. For this purpose, collect samples in pre-cleaned, acid-soaked polyethylene bottles. Add 2 mL conc HNO3/L sample and mix well. Cap tightly and store in refrigerator until ready for analysis. Metal concentrations were determined using inductively coupled plasma- optical emission spectrometry (ICP-OES. Results: The results showed that mean concentrations of As, Zn, Pb, Cd and Cu in groundwater samples in spring season were 52.53±13.62, 15.51±23.45, 10.10±2.80, 4.48±1.80 and 8.63±10.87 μg l−1, respectively and in summer season were 57.60±16.90, 14.99±17.66, 9.28±2.46, 4.57±1.73 and 10.45±10.30 μg l−1, respectively. Therefore the mean values of indices in samples from spring and summer seasons were 25.61 and 27.28 respectively for HPI and were 9.29 and 8.88 respectively for HEI, and indicates low contamination levels. Comparing the mean concentrations of the evaluated metals with WHO permissible limits showed a significant difference (P<0.05. Thus, the mean concentrations of the metals were significantly lower than the permissible limits. Conclusions: Despite of the heavy metal pollution of the groundwater resources in Asadabad Plain is lower than WHO permissible limits, but the irregular and long-term usage of agricultural inputs, use of wastewater and sewage sludge in agriculture, over use of organic fertilizers and establishment of pollutant industries can threaten the groundwater resources of this

  1. Ground-water resources in the Hood Basin, Oregon

    Science.gov (United States)

    Grady, Stephen J.

    1983-01-01

    iron (0.3 to 6.4 milligrams per liter) and manganese (0.05 to 1.2 milligrams per liter) or is moderately hard to very hard (60 to 260 milligrams per liter as CaCO3).The principal use of ground water in the Hood Basin is for irrigation of crops, with an estimated withdrawal of 7,700 acre-feet in 1979. Additional ground-water withdrawals in 1979 were estimated as: Industrial, 2,600 acre-feet; public supply, 2,100 acre-feet; and domestic and stock supply, 200 acre-feet.

  2. Genesis of economic relevant fresh groundwater resources in Pleistocene/ Neogene aquifers in Nam Dinh (Red River Delta, Vietnam).

    Science.gov (United States)

    Wagner, F.; Ludwig, R. R.; Noell, U.; Hoang, H. V.; Pham, N. Q.; Larsen, F.; Lindenmaier, F.

    2012-04-01

    Holocene sediments. Consequently, 14C groundwater age dating suggests increasing groundwater ages from fresh to saline pore water in Pleistocene and Neogene up to 14 ka, presuming that contamination with dead carbon is neglectable. Highest 14C ages of low saline water has been observed in the center of the exploited fresh water lens reaching up to 10 ka, reflecting low groundwater flux and recharge rates. Due to the overexploitation, the natural coastward directed groundwater flow has turned towards the centre of the abstraction cone with horizontal apparent velocities of up to 0.6 m/a. This suggests, that brackish and higher saline groundwater from the Red River area (East Nam Dinh) and offshore migrates towards the fresh water lens. Thus, more sustainable exploitation strategies urgently must be implemented to reduce overexploitation of limited and valuable fresh groundwater resources in Nam Dinh Province. Reference: Hoan H., Pham Q. N., Larsen F. Tran L. V., Wagner F., Christiansen A.V. (2010): Processes Controlling High Saline Groundwater in the Nam Dinh Province, Vietnam. 2nd Asia-Pacific Coastal Aquifer Management Meeting (ACAMM), October 18-21, 2011, Jeju Island, Korea.

  3. Geology and ground-water resources of Rock County, Wisconsin

    Science.gov (United States)

    LeRoux, E.F.

    1964-01-01

    . This sandstone also yields some water to uncased wells that tap the deeper rocks of the Upper Cambrian series. East of the Rock River the Platteville, Decorah, and Galena formations undifferentiated, or Platteville-Galena unit, is the principal source of water for domestic and stock wells. Unconsolidated deposits of glacial origin cover most of Rock County and supply water to many small wells. In the outwash deposits along the Rock River, wells of extremely high capacity have been developed for industrial and municipal use. The most significant feature of the bedrock surface in Rock County is the ancestral Rock River valley, which has been filled with glacial outwash to a depth of at least 396 feet below the present land surface. East of the buried valley the bedrock has a fiat, relatively undissected surface. West of the valley the bedrock surface is rugged and greatly dissected. Ground water in Rock County occurs under both water-table and artesian conditions; however, because of the interconnection and close relation of all ground water in the county, the entire system is considered to be a single groundwater body whose surface may be represented by one piezometric map. Recharge occurs locally, throughout the county. Nearly all recharge is derived directly from precipitation that percolates downward to become a part of the groundwater body. Natural movement of water in the consolidated water-bearing units is generally toward the buried Rock and Sugar River valleys. Movement of water in the sandstones of Cambrian age was calculated to be about 44 million gallons a day toward the Rock River. Discharge from wells in Rock County in 1957 was about 23 million gallons a day. Nearly 90 percent of this water was drawn from the area along the Rock River. Drilled wells, most of which were drilled by the cable-tool method, range in diameter from 3 to 26 inches, and in depth from 46 to 1,225 feet. Driven wells in alluvium and glacial drift are usually 1? to 2? in

  4. Web GIS design and realization for groundwater resources in the Yellow River basin

    Institute of Scientific and Technical Information of China (English)

    GAO; Jianguo; GONG; Huili; ZHAO; Wenji; ZHANG; Xiaosong; Y

    2004-01-01

    This article brings forward a design and realization scheme of Web GIS in the Yellow River basin for the management of groundwater resources. The main goals are to manage and share data of massive-scale, to support the research of groundwater resources in the Yellow River basin. In this paper we point out the necessity and feasibility of building the distributed Web GIS for geographical research objects on a large scale.We put forward some solutions for the construction of this kind of system including a holistic deployment strategy in the Internet, a scheme of distributed data storage and management, a design of application structure based on three tires architecture by each province and how they collaborate with each other. It also illuminates how the application server works, and sets forth the relations among databases which work together in this system.

  5. GREAT (Groundwater Resources & Educational Activities for Teaching). An Iowa Project for Earth/Life/General Science, 7th-9th Grades.

    Science.gov (United States)

    George, Gail, Ed.

    These resource materials are a part of a larger plan for groundwater education, as detailed in the Iowa Groundwater Education Strategy. The six units are arranged in priority order. The first unit covers the basics of groundwater and hydrogeology in Iowa. The other five units cover Iowa's groundwater issues in priority order, as outlined in the…

  6. The Impact of Water Diversion on Groundwater Resources in an Inland River Basin

    Science.gov (United States)

    Huang, L.; Zheng, C.

    2012-12-01

    The Heihe River Basin (HRB) is one of the most intensely exploited and ecologically stressed inland river basins in the world. The HRB is characterized by three distinct ecohydrological systems: the mountainous upper reach where most of the water resources for the HRB originate from the rainfall, snow and permafrost; the middle reach with an arid climate and irrigated agriculture; and the lower reach dominated by wide stretches of Gobi desert. The study site, Zhangye Basin, is situated in the middle reach. It contains 92% population of the HRB and consumes about 80% of water resources as a regional agricultural and industrial center. To improve the deteriorating health of the ecosystems in the lower HRB, the Chinese government initiated the Heihe Water Diversion Project (HWDP) in 2000, which stipulated that at least 0.95 billion cubic meters of surface water must be delivered from the middle reach to the lower reach annually. A three-dimensional groundwater flow model has been developed for the Zhangye Basin to understand groundwater-surface water interactions in the Zhangye Basin and assess how the HWDP project has impacted the groundwater availability and water budgets in the region. The flow model has been reasonably calibrated using multiple sources of field data. The output of the groundwater model provided estimates of head differences before and after the HWDP project between 1999 and 2010. The results show that the groundwater level has declined widely, except in the Zhangye urban area where the groundwater level has increased by 0.5 to 7m and a few other localized spots. The calculated water budgets indicate that the spring discharge to the Heihe River has been continuously decreasing, and the total river leakage to the aquifer has been increasing. These results are in reasonable agreement with those from previous studies based on independent water balance calculation. The groundwater model is being integrated with surface water and land use data to

  7. Groundwater recharge in the tropics: a pan-African analysis of observations

    Science.gov (United States)

    Taylor, R. G.

    2015-12-01

    Groundwater is a vital source of freshwater in sub-Saharan Africa where rainfall and river discharge are unreliable and per-capita reservoir storage is among the lowest in the world. Groundwater is widely considered a distributed, low-cost and climate-resilient option to meet rapidly growing freshwater demand and alleviate endemic poverty by expanding access to safe water and improving food security through irrigation. Recent research indicates that groundwater storage in Africa is about 100 times greater than annual river discharge yet major uncertainties remain in the magnitude and nature of replenishment through recharge as well as the impacts of land-use and climate change. Here, we present newly compiled, multi-decadal observations of groundwater levels from 5 countries (Benin, Burkina Faso, Niger, Tanzania, Uganda) and paired measurements of stable isotope ratios of O and H in precipitation and groundwater at 11 locations. These data reveal both a distinct bias in groundwater recharge to intensive rainfall and rapid recharge pathways (e.g. focused, macropore flow) that are inconsistent with conventional recharge models assuming pore-matrix flow defined by the Darcy-Richards equation. Further the records highlight the substantial influence of land-use change (e.g. conversion of natural, perennial cover to croplands) on groundwater recharge. The compiled observations also provide, for the first time, a pan-African baseline to evaluate the performance of large-scale hydrological models and Land-Surface Models incorporating groundwater in this region. Our results suggest that the intensification of precipitation brought about by global warming favours groundwater replenishment in sub-Saharan Africa. As such, groundwater may prove to be a climate-resilient source of freshwater in the tropics, enabling adaptive strategies such as groundwater-fed irrigation and sustaining domestic and industrial water supplies.

  8. Forecasting the Depletion of Transboundary Groundwater Resources in Hyper-Arid Environments

    Science.gov (United States)

    Mazzoni, A.; Heggy, E.

    2014-12-01

    The increase in awareness about the overexploitation of transboundary groundwater resources in hyper-arid environments that occurred in the last decades has highlighted the need to better map, monitor and manage these resources. Climate change, economic and population growth are driving forces that put more pressure on these fragile but fundamental resources. The aim of our approach is to address the question of whether or not groundwater resources, especially non-renewable, could serve as "backstop" water resource during water shortage periods that would probably affect the drylands in the upcoming 100 years. The high dependence of arid regions on these resources requires prudent management to be able to preserve their fossil aquifers and exploit them in a more sustainable way. We use the NetLogo environment with the FAO Aquastat Database to evaluate if the actual trends of extraction, consumption and use of non-renewable groundwater resources would remain feasible with the future climate change impacts and the population growth scenarios. The case studies selected are three: the Nubian Sandstone Aquifer System, shared between Egypt, Libya, Sudan and Chad; the North Western Sahara Aquifer System, with Algeria, Tunisia and Libya and the Umm Radhuma Dammam Aquifer, in its central part, shared between Saudi Arabia, Qatar and Bahrain. The reason these three fossil aquifers were selected are manifold. First, they represent properly transboundary non-renewable groundwater resources, with all the implications that derive from this, i.e. the necessity of scientific and socio-political cooperation among riparians, the importance of monitoring the status of shared resources and the need to elaborate a shared management policy. Furthermore, each country is characterized by hyper-arid climatic conditions, which will be exacerbated in the next century by climate change and lead to probable severe water shortage periods. Together with climate change, the rate of population

  9. Summary appraisals of the Nation's ground-water resources; Souris-Red-Rainy region

    Science.gov (United States)

    Reeder, Harold O.

    1978-01-01

    A broad-perspective analysis of the ground-water resources and present and possible future water development and management in the Souris-Red-Rainy Region is presented. The region includes the basins of the Souris River within Montana and North Dakota; the Red River of the North in South Dakota, North Dakota, and Minnesota; and the Rainy River within Minnesota. The region includes 59,645 square miles, mostly in North Dakota and Minnesota.

  10. Sustainable Management of Groundwater Resources on a Tropical Island: Issues and Dillemmas

    OpenAIRE

    Johnstone, Ron; Gossling, Stefan

    1998-01-01

    Many developing countries have focused on tourism to generate additional income sources and to diversify the economy. The development of the necessary infrastructure in combination with the presence of a large number of tourists can have detrimental effects for the resource base on which local communities depend. In this article, the situation is described for the East Coast of Zanzibar, Tanzania. Causes and consequences of groundwater withdrawal are investigated, analyzed and put into contex...

  11. Selection of spatial scale for assessing impacts of groundwater-based water supply on freshwater resources.

    Science.gov (United States)

    Hybel, A-M; Godskesen, B; Rygaard, M

    2015-09-01

    Indicators of the impact on freshwater resources are becoming increasingly important in the evaluation of urban water systems. To reveal the importance of spatial resolution, we investigated how the choice of catchment scale influenced the freshwater impact assessment. Two different indicators were used in this study: the Withdrawal-To-Availability ratio (WTA) and the Water Stress Index (WSI). Results were calculated for three groundwater based Danish urban water supplies (Esbjerg, Aarhus, and Copenhagen). The assessment was carried out at three spatial levels: (1) the groundwater body level, (2) the river basin level, and (3) the regional level. The assessments showed that Copenhagen's water supply had the highest impact on the freshwater resource per cubic meter of water abstracted, with a WSI of 1.75 at Level 1. The WSI values were 1.64 for Aarhus's and 0.81 for Esbjerg's water supply. Spatial resolution was identified as a major factor determining the outcome of the impact assessment. For the three case studies, WTA and WSI were 27%-583% higher at Level 1 than impacts calculated for the regional scale. The results highlight that freshwater impact assessments based on regional data, rather than sub-river basin data, may dramatically underestimate the actual impact on the water resource. Furthermore, this study discusses the strengths and shortcomings of the applied indicator approaches. A sensitivity analysis demonstrates that although WSI has the highest environmental relevance, it also has the highest uncertainty, as it requires estimations of non-measurable environmental water requirements. Hence, the development of a methodology to obtain more site-specific and relevant estimations of environmental water requirements should be prioritized. Finally, the demarcation of the groundwater resource in aquifers remains a challenge for establishing a consistent method for benchmarking freshwater impacts caused by groundwater abstraction.

  12. Interannual to Multidecadal Climate Variability and Groundwater Resources of the Western United States

    Science.gov (United States)

    Gurdak, J. J.; Kuss, A. M.

    2011-12-01

    Climate variability and change have important implications for groundwater recharge, discharge, contaminant transport, and resource sustainability. Reliable predictions of groundwater sustainability due to climate change will require improved understanding of the effects of global scale atmosphere-ocean climate oscillations on interannual to multidecadal timescales. Climate variability on these timescales partially controls precipitation, air temperature, drought, evapotranspiration, streamflow, recharge, and mobilization of subsurface-chemical reservoirs. Climate variability can augment or diminish human stresses on groundwater, and the responses in storage can be dramatic when different climate cycles lie coincident in a positive or negative phase of variability. Thus, understanding climate variability has particular relevance for management decisions during drought and for water resources close to the limits of sustainability. Major findings will be presented from a national scale study of climate variability on recharge rates and groundwater levels, and will highlight regional aquifers of the western United States, including the Basin and Range (700,000 km2), Central Valley (52,000 km2), High Plains (450,000 km2), and Mississippi Embayment (181,000 km2) aquifer systems. Using singular spectrum analysis, the groundwater pumping signal was removed and natural variations were identified in groundwater levels as partially coincident with the El Niño/Southern Oscillation (ENSO) (2-6 year cycle), North Atlantic Oscillation (3-6 year cycle), Pacific Decadal Oscillation (PDO) (10-25 year cycle), and Atlantic Multidecadal Oscillation (AMO) (50-80 year cycle). The PDO was the most significant contributor to recharge and groundwater level fluctuations in most aquifers. In the Central Valley and the Basin and Range, the PDO contributes to the greatest amount of variance (ranging from 13.6-83%) in all precipitation and groundwater level time series, with moderate to strong

  13. Potential impacts on groundwater resources of deep CO2 storage: natural analogues for assessing potential chemical effects

    Science.gov (United States)

    Lions, J.; Gale, I.; May, F.; Nygaard, E.; Ruetters, H.; Beaubien, S.; Sohrabi, M.; Hatzignatiou, D. G.; CO2GeoNet Members involved in the present study Team

    2011-12-01

    Carbon dioxide Capture and Storage (CCS) is considered as one of the promising options for reducing atmospheric emissions of CO2 related to human activities. One of the main concerns associated with the geological storage of CO2 is that the CO2 may leak from the intended storage formation, migrate to the near-surface environment and, eventually, escape from the ground. This is a concern because such leakage may affect aquifers overlying the storage site and containing freshwater that may be used for drinking, industry and agriculture. The IEA Greenhouse Gas R&D Programme (IEAGHG) recently commissioned the CO2GeoNet Association to undertake a review of published and unpublished literature on this topic with the aim of summarizing 'state of the art' knowledge and identifying knowledge gaps and research priorities in this field. Work carried out by various CO2GeoNet members was also used in this study. This study identifies possible areas of conflict by combining available datasets to map the global and regional superposition of deep saline formations (DSF) suitable for CO2 storage and overlying fresh groundwater resources. A scenario classification is developed for the various geological settings where conflict could occur. The study proposes two approaches to address the potential impact mechanisms of CO2 storage projects on the hydrodynamics and chemistry of shallow groundwater. The first classifies and synthesizes changes of water quality observed in natural/industrial analogues and in laboratory experiments. The second reviews hydrodynamic and geochemical models, including coupled multiphase flow and reactive transport. Various models are discussed in terms of their advantages and limitations, with conclusions on possible impacts on groundwater resources. Possible mitigation options to stop or control CO2 leakage are assessed. The effect of CO2 pressure in the host DSF and the potential effects on shallow aquifers are also examined. The study provides a review of

  14. Analysis of the potential contamination risk of groundwater resources circulating in areas with anthropogenic activities

    Directory of Open Access Journals (Sweden)

    M. Spizzico

    2005-01-01

    Full Text Available The area investigated is located in the province of Brindisi (Italy. It is a generally flat area separated from the nearby carbonatic plateau of the Murgia by quite indistinct and high fault scarps. As regards the geological features, carbonatic basement rocks and post-cretaceous terrains made up of calabrian calcarenites and middle-upper Pleistocenic marine terraced deposits can be distinguished. In the examined area there are two different hydrogeological environments. The first is represented by deep groundwater, the main groundwater resource in Apulia. The second hydrogeological environment, now of lesser importance than the deep aquifer in terms of size and use, is made up of some small shallow groundwater systems situated in post-calabrian sands and located in the eastern area. During some sampling cycles carried out in the studied area, water was withdrawn from both the deep aquifer and from the shallow groundwater. For every sample, the necessary parameters were determined for the physical and chemical characterisation of two different hydrogeological environments. Moreover, some chemical parameters indicating anthropogenic activities were determined. Analysis of the aerial distribution of the measured parameters has shown some main areas subject to different conditions of contamination risk, in accordance with the hydrogeological and geological features of the investigated area. In the south-eastern part of the investigated area, the important action performed by the surface aquifer for protecting the deep groundwater from contamination of anthropogenic origin is clear. On the other hand, in the shallow groundwater, areas of nitrate and nitrite contamination have been identified, which result from the extensive use of fertilizers.

  15. Groundwater assessment in water resources management at Nuclear and Energy Research Institute, Brazil

    Energy Technology Data Exchange (ETDEWEB)

    Soares, Sabrina M.V.; Marques, Joyce R.; Monteiro, Lucilena R.; Stellato, Thamiris B.; Silva, Tatiane B.S.C.; Faustino, Mainara G.; Silva, Douglas B. da; Cotrim, Marycel E.B.; Pires, Maria Aparecida F., E-mail: sabrinamoura@usp.br, E-mail: joyce.marques@usp.br, E-mail: luciremo@uol.com.br, E-mail: thamistellato@gmail.com, E-mail: tatianebscs@live.com, E-mail: mainarag@usp.br, E-mail: douglas.sbatista@yahoo.com.br, E-mail: mecotrim@ipen.br, E-mail: mapires@ipen.br [Instituto de Pesquisas Energeticas e Nucleares (IPEN/CNEN-SP), Sao Paulo, SP (Brazil)

    2015-07-01

    To comply with the guidelines for environmental control and legal requirements, the Nuclear and Energy Research Institute (IPEN/ CNEN - Brazil/ SP) performs the Environmental Monitoring Program for Chemical Stable Compounds (PMA-Q) since 2007, in attendance to the Term for the Adjustment of Conduct (TAC) signed between IPEN and the Brazilian Institute of Environment and Renewable Natural Resources (IBAMA). The PMA-Q program includes the assessment of the IPEN's wastewater released in water body, and the groundwater assessment, which is carried out in nine monitoring wells. In groundwater is analyzed, by ion chromatography, species regulated by CONAMA 396/08 [01] fluoride, chloride, nitrite-N, nitrate-N, sulfate, sodium, potassium, ammonium, magnesium and calcium, besides other parameters. Furthermore, based on legal requirements, each year the program is reviewed and improvement actions are planned and implemented. Therefore, the integrated monitoring of groundwater should provide information on the quality and dynamics of the aquifer compared to seasonal variations and anthropogenic effects. Thus, this study intends to evaluate the chemical features of the institute groundwater, evaluating the database of the monitoring program from 2011 to 2014, for the ions chloride, nitrate-N, sulfate, sodium, potassium, magnesium, calcium and bicarbonate, using these information diagrams will be developed for the characterization of the wells. This assessment will be essential to support the control actions of environmental pollution and the management of water resources. Making possible the establishment of groundwater Quality Reference Figures (QRF), according to the CONAMA 396/08 [01] rating, in order to demonstrate that the activities developed at IPEN are not affecting on the aquifer features. (author)

  16. Composite Analysis of Landuse and Groundwater Resources of Rod-Kohi

    Directory of Open Access Journals (Sweden)

    Arshad Ashraf

    2015-01-01

    Full Text Available Rod-kohi system of irrigation is often generally referred to as flood irrigation or spate irrigation system in which floods of the hill torrents are diverted into plain area for irrigation purpose. In rod-kohi region where uncertainty exists in flood water availability for irrigation use, groundwater is a valuable resource used mainly as supplement source of irrigation. The region, being rich in natural resources, is remained far behind in terms of data availability and data quality, the situation that has affected incredibly the needs of future planning and development. In the present study, major landuse/landcover classes of the region were identified and delineated using Landsat ETM+ (Enhanced Thematic Mapper Plus image data and related with groundwater potential for interactive analysis in GIS (Geographic Information System. The potential groundwater zones were delineated and assessed on the basis of aquifer characteristics in the region. Rangeland and exposed rocks were identified over 70% of the rod-kohi region i.e. total area about 42 Mha (Million hectares. Share of cropped area and bare soil or culturable waste was about 3.5 and 15.4%, respectively. High and medium potential of groundwater were estimated in about 2.3 Mha out of which 60% exist under bare soil, 16% under cropped area and the rest underneath other landuse classes. High efficiency irrigation techniques like drip and rain-gun system need to be adopted in areas having substantial groundwater potential in order to sustain agriculture production. The study would provide base for detail investigation

  17. A Geo-Environmental Analysis of the Groundwater Resource vis-a-vis Surface Water Scenario in Guwahati City

    Directory of Open Access Journals (Sweden)

    Neelkamal Das

    2013-08-01

    Full Text Available Guwahati city is located on a unique geo-environmental setting with an interface of hills and valleys along with a prominent river front. The existence of various surface water sources, geo-hydrological set up and rainfall intensity play a significant role in the ground water regime of the city. However, rapid urbanisation of the city during the last few decades has altered the landscape of the city and disturbed the water retention capacity as well as the flow dynamics of various surface water sources, thereby affecting the infiltration rate to a great extent. Unprecedented rise in the population of the city has exerted more pressure on the various sources of water, particularly the groundwater resource. It has thus become imperative to utilise the various sources of water in a more systematic and scientific manner, giving due emphasis to the water requirement and the prevailing hydrological conditions of the area. Moreover, it is also observed that the city experiences an average annual rainfall of 162 cm with about 110 rainy days per year. The city thus has enough potential for harvesting the rainwater it receives, instead of allowing it to flow untapped. Rainwater can be tapped and utilised to revive the various surface water sources of the city, thereby facilitating natural groundwater recharge, as surface water bodies like wetlands, lakes and ponds do act as potential groundwater recharge zones.

  18. Explaining nitrate pollution pressure on the groundwater resource in Kinshasa using a multivariate statistical modelling approach

    Science.gov (United States)

    Mfumu Kihumba, Antoine; Vanclooster, Marnik

    2013-04-01

    Drinking water in Kinshasa, the capital of the Democratic Republic of Congo, is provided by extracting groundwater from the local aquifer, particularly in peripheral areas. The exploited groundwater body is mainly unconfined and located within a continuous detrital aquifer, primarily composed of sedimentary formations. However, the aquifer is subjected to an increasing threat of anthropogenic pollution pressure. Understanding the detailed origin of this pollution pressure is important for sustainable drinking water management in Kinshasa. The present study aims to explain the observed nitrate pollution problem, nitrate being considered as a good tracer for other pollution threats. The analysis is made in terms of physical attributes that are readily available using a statistical modelling approach. For the nitrate data, use was made of a historical groundwater quality assessment study, for which the data were re-analysed. The physical attributes are related to the topography, land use, geology and hydrogeology of the region. Prior to the statistical modelling, intrinsic and specific vulnerability for nitrate pollution was assessed. This vulnerability assessment showed that the alluvium area in the northern part of the region is the most vulnerable area. This area consists of urban land use with poor sanitation. Re-analysis of the nitrate pollution data demonstrated that the spatial variability of nitrate concentrations in the groundwater body is high, and coherent with the fragmented land use of the region and the intrinsic and specific vulnerability maps. For the statistical modeling use was made of multiple regression and regression tree analysis. The results demonstrated the significant impact of land use variables on the Kinshasa groundwater nitrate pollution and the need for a detailed delineation of groundwater capture zones around the monitoring stations. Key words: Groundwater , Isotopic, Kinshasa, Modelling, Pollution, Physico-chemical.

  19. Groundwater renewable resources in karst areas, the case of the Kleśnica River basin (Sudety Mountains, Poland)

    Science.gov (United States)

    Olichwer, Tomasz; Otrębski, Adrian

    2016-12-01

    The karst-fractured medium constitutes a considerable groundwater capacity, as shown on the example of the Kleśnica River basin. The paleozoic crystalline limestones in the research area are good collectors of the groundwater. The Kleśnica River basin, one of the largest crystalline limestone lens, is situated in the Sudety Mountains. Groundwater renewable resources were distinguished with the use of hydrological methods, on the basis of hydrometric measurements of the flow discharge of the Kleśnica River during the low-flow period (2009-2010). The mean module of the groundwater runoff equals 20.79 dm3/s*km2, and includes the study of the river catchments areas with extremely high groundwater runoff. The groundwater renewable resources in the Kleśnica River basin are almost twice higher than in the neighbouring river basins (the Kamienica and Morawka River basins), in which there are no significant outcrops of carbonate rocks. These considerable renewable resources also provide a high runoff in the spring, 7.98 dm3/s*km2. The high values of the runoffs indicate, that the groundwater is coming from the regional circulation system and, on a smaller scale, from the local system. The groundwater from both systems flows into the fractured system through the karst of carbonate massif rocks and their weathering fringes.

  20. Strain Observation Affected by Groundwater-Level Change in Seismic Precursor Monitoring

    Science.gov (United States)

    Zhang, Lei; Cao, Daiyong; Zhang, Jingfa

    2017-03-01

    Groundwater extraction is one of the most typical disturbance factors for strain observation in seismic precursor monitoring. The statistic regression method is used to study based on the relation between the variation of strain and the groundwater level. The least square regression linear model is built between the annual variation of Sangzi groundwater level and the Xiaoxinzhuang strain data. Such model meets t test with significance level α = 0. 0 5, which confirms that groundwater-level change in each year affects strain measurement significantly and strain's trend variation is related to groundwater-level change. Consequently, a new correction method about strain data is put forward based on the groundwater-level annual variation to eliminate the trend change. Results indicate that the accumulated residual deformation causes the horizontal displacement and strain change, which is on account of that the amount of groundwater recharge is less than that of extraction around Xiaoxinzhuang cave, the phreatic surface continues to descend, and residual deformation accumulates and leads to local subsidence area. Therefore, the decline trend change of strain is related to groundwater-level change and is not seismic precursor.

  1. Conjunctive management of surface and groundwater resources under projected future climate change scenarios

    Science.gov (United States)

    Mani, Amir; Tsai, Frank T.-C.; Kao, Shih-Chieh; Naz, Bibi S.; Ashfaq, Moetasim; Rastogi, Deeksha

    2016-09-01

    This study introduces a mixed integer linear fractional programming (MILFP) method to optimize conjunctive use of future surface water and groundwater resources under projected climate change scenarios. The conjunctive management model maximizes the ratio of groundwater usage to reservoir water usage. Future inflows to the reservoirs were estimated from the future runoffs projected through hydroclimate modeling considering the Variable Infiltration Capacity model, and 11 sets of downscaled Coupled Model Intercomparison Project phase 5 global climate model projections. Bayesian model averaging was adopted to quantify uncertainty in future runoff projections and reservoir inflow projections due to uncertain future climate projections. Optimized conjunctive management solutions were investigated for a water supply network in northern Louisiana which includes the Sparta aquifer. Runoff projections under climate change scenarios indicate that runoff will likely decrease in winter and increase in other seasons. Results from the developed conjunctive management model with MILFP indicate that the future reservoir water, even at 2.5% low inflow cumulative probability level, could counterbalance groundwater pumping reduction to satisfy demands while improving the Sparta aquifer through conditional groundwater head constraints.

  2. An integrated hydrogeological study to support sustainable development and management of groundwater resources: a case study from the Precambrian Crystalline Province, India

    Science.gov (United States)

    Madhnure, Pandith; Peddi, Nageshwar Rao; Allani, Damodar Rao

    2016-03-01

    The rapid expansion of agriculture, industries and urbanization has triggered unplanned groundwater development leading to severe stress on groundwater resources in crystalline rocks of India. With depleting resources from shallow aquifers, end users have developed resources from deeper aquifers, which have proved to be counterproductive economically and ecologically. An integrated hydrogeological study has been undertaken in the semi-arid Madharam watershed (95 km2) in Telangana State, which is underlain by granites. The results reveal two aquifer systems: a weathered zone (maximum 30 m depth) and a fractured zone (30-85 m depth). The weathered zone is unsaturated to its maximum extent, forcing users to tap groundwater from deeper aquifers. Higher orders of transmissivity, specific yield and infiltration rates are observed in the recharge zone, while moderate orders are observed in an intermediate zone, and lower orders in the discharge zone. This is due to the large weathering-zone thickness and a higher sand content in the recharge zone than in the discharge zone, where the weathered residuum contains more clay. The NO3 - concentration is high in shallow irrigation wells, and F- is high in deeper wells. Positive correlation is observed between F- and depth in the recharge zone and its proximity. Nearly 50 % of groundwater samples are unfit for human consumption and the majority of irrigation-well samples are classed as medium to high risk for plant growth. Both supply-side and demand-side measures are recommended for sustainable development and management of this groundwater resource. The findings can be up-scaled to other similar environments.

  3. Calculation of an interaction index between extractive activity and groundwater resources

    Science.gov (United States)

    Collier, Louise; Hallet, Vincent; Barthélemy, Johan; Moriamé, Marie; Cartletti, Timotéo

    2015-04-01

    There are two underground resources intensively exploited in Wallonia (the southern Region of Belgium): groundwater and rock. Groundwater production rate is about 380*106 cubic meter per year from which 80 % is used for drinking water (SPW-DGO3, 2014). Annual rock extraction is about 73*106 tons per year and 80.6% of the materials are carbonate rocks (Collier and Hallet, 2013) corresponding to the most important aquifer formations. Given the high population density and environmental pressures, lateral quarry extensions are limited and the only solution for the operators is to excavate deeper. In this context, the aquifer level of the exploited formation is often reached and dewatering systems have to be installed to depress the water table below the quarry pit bottom. This affects the regional hydrogeology and, in some cases, the productivity of the water catchments is threatened. Using simple geological and hydrogeological parameters, an interaction index was developed to assess the interaction between extractive activity and groundwater resources and, in consequence, to define how far the feasibility study should go into detailed hydrogeological investigations. The interaction index is based on the equation used in the assessment of natural hazards (Dauphiné, 2003), which gives: Interaction = F (Quarry, Aquifer). The interaction is the risk, which is equal to a function where the hazard is defined from parameters corresponding to the quarry and vulnerability from parameters related to groundwater resources. Six parameters have been determined. The parameters chosen to represent the hazard of a quarry are: the geological, the hydrogeological and the piezometric contexts. The parameters chosen to represent the vulnerability of the water resources are: the relative position between the quarry and the water catchment (well, spring, gallery, etc.) sites, the productivity of the catchment and the quality of the groundwater. Each parameter was classified into four

  4. Ground-water resources of the Houston district, Texas

    Science.gov (United States)

    White, Walter N.; Rose, N.A.; Guyton, William F.

    1944-01-01

    This report covers the current phase of an investigation of the supply of ground water available for the Houston district and adjacent region, Texas,- that has been in progress during the past 10 years. The field operations included routine inventories of pumpage, measurements of water levels in observation wells and collection of other hydrologic data, pumping tests on 21 city-owned wells to determine coefficients of permeability and storage, and the drilling of 13 deep test wells in unexplored parts of the district. Considerable attention has been given to studies of the location of areas or beds of sand that contain salt water. The ground water occurs in beds of sand, sandstone, and gravel of Miocene, Pliocene, and Pleistocene age. These formations crop out in belts that dip southeastward from their outcrop areas and are encountered by wells at progressively greater depths toward the southeast. The beds throughout the section are lithologically similar, and there is little agreement among geologists as to their correlation. -In this investigation, however, the sediments, penetrated by the wells are separated into six zones, chiefly on the basis of electrical logs. Most of the water occurs in zone 3, which ranges in thickness from 800 to 1,200 feet. Large quantities of ground water are pumped in three areas in the Houston district, as follows: The Houston tromping area, which includes Houston and the areas immediately adjacent; the Pasadena pumping area, which includes the industrial section extending along the ship channel from the Houston city limits eastward to Deer Park; and the Katy pumping area, an irregular-shaped area of several hundred square miles, which is roughly centered around the town of Katy, 30 miles west of Houston. In 1930 the total combined withdrawal of ground water in the Houston and Pasadena pumping areas averaged about 50 million gallons a day. It declined somewhat during 1932 and 1933 and then gradually increased, until in 1935 the total

  5. GIS based Hydrogeological Vulnerability Mapping of Groundwater Resources in Jerash Area-Jordan

    Energy Technology Data Exchange (ETDEWEB)

    Hammouri, N [Department of Earth and Environmental Sciences, Faculty of Natural Resources and Environment, Hashemite University, Zarqa (Jordan); El-Naqa, A [Department of Water Management and Environment, Faculty of Natural Resources and Environment, Hashemite University, Zarqa (Jordan)

    2008-04-15

    This paper presents groundwater vulnerability mapping for Jerash area, north Jordan generated using EPIK and DRASTIC models. These models have been implemented using GIS to delineate groundwater protection zones and to suggest a protection plan to improve groundwater quality of the major springs and wells. Most of the groundwater resources in the study area are polluted and bacteria and nitrate levels are high. Different sources of groundwater pollution have been identified. Domestic wastewater is considered as a major source of pollution. Urban runoff, fertilizers from agricultural return flows and solid waste disposal appear to be secondary sources. The most relevant vulnerability class of EPIK map is very high which accounts for about 41 % of the total area. While in the DRASTIC vulnerability map, areas with high vulnerability were only about 23 % of the total area. There is a good correlation between vulnerability maps obtained from both models with microbiological and chemical pollution evidences. There is also a good agreement between the areas classified as highly vulnerable and those that have high levels of pollution. [Spanish] El estudio de vulnerabilidad de aguas subterraneas en la region de Yerash, Jordania fue obtenido mediante las metodologias de EPIK y DRASTIC. Se uso GIS para mapear las zonas protegidas y para sugerir un plan de proteccion para mejorar la calidad del agua subterranea en los principales manantiales y pozos. Los niveles de contaminacion bacteriana y de nitratos son elevados. El efluente domestico es la fuente mas importante de contaminacion; vienen en segundo lugar la precipitacion en zonas urbanas, los fertilizantes agricolas y los desechos solidos. En el mapa de EPIK, la vulnerabilidad extrema abarca hasta 41% del area total; en cambio, en el mapa de DRASTIC las areas de alta vulnerabilidad ocupan solo un 23% del area. La correlacion de los datos de contaminacion microbiana y quimica con ambos mapas der vulnerabilidad es buena

  6. A decomposition approach for optimal management of groundwater resources and irrigated agriculture in arid coastal regions

    Science.gov (United States)

    Grundmann, Jens; Schütze, Niels; Heck, Vera

    2013-04-01

    For ensuring an optimal sustainable water resources management in arid coastal environments, we develop a new simulation based integrated water management system. It aims at achieving best possible solutions for groundwater withdrawals for agricultural and municipal water use including saline water management together with a substantial increase of the water use efficiency in irrigated agriculture. To achieve a robust and fast operation of the management system, it unites process modelling with artificial intelligence tools and evolutionary optimisation techniques for managing both, water quality and water quantity of a strongly coupled groundwater-agriculture system. However, such systems are characterized by a large number of decision variables if abstraction schemes, cropping patterns and cultivated acreages are optimised simultaneously for multiple years. Therefore, we apply the principle of decomposition to separate the original large optimisation problem into smaller, independent optimisation problems which finally allow for a faster and more reliable solution. At first, within an inner optimisation loop, cropping patterns and cultivated acreages are optimised to achieve a most profitable agricultural production for a given amount of water. Thereby, the behaviour of farms is described by crop-water-production functions which can be derived analytically. Secondly, within an outer optimisation loop, a simulation based optimisation is performed to find optimal groundwater abstraction pattern by coupling an evolutionary optimisation algorithm with an artificial neural network for modelling the aquifer response, inclusive the seawater interface. We demonstrate the decomposition approach by an exemplary application of the south Batinah region in the Sultanate of Oman which is affected by saltwater intrusion into a coastal aquifer system due to excessive groundwater withdrawal for irrigated agriculture. We show the effectiveness of our methodology for the evaluation

  7. Characterization of groundwater resources in the Trinity and Woodbine aquifers in Texas.

    Science.gov (United States)

    Chaudhuri, Sriroop; Ale, Srinivasulu

    2013-05-01

    A vast region in north-central Texas, centering on Dallas-Fort Worth metroplex, suffers from intense groundwater drawdown and water quality degradation, which led to inclusion of 18 counties of this region into Priority Groundwater Management Areas. We combined aquifer-based and county-based hydrologic analyses to (1) assess spatio-temporal changes in groundwater level and quality between 1960 and 2010 in the Trinity and Woodbine aquifers underlying the study region, (2) delve into major hydrochemical facies with reference to aquifer hydrostratigraphy, and (3) identify county-based spatial zones to aid in future groundwater management initiatives. Water-level and quality data was obtained from the Texas Water Development Board (TWDB) and analyzed on a decadal scale. Progressive water-level decline was the major concern in the Trinity aquifer with >50% of observations occurring at depths >100 m since the 1980s, an observation becoming apparent only in the 2000s in the Woodbine aquifer. Water quality degradation was the major issue in the Woodbine aquifer with substantially higher percentage of observations exceeding the secondary maximum contaminant levels (SMCL; a non-enforceable threshold set by the United State Environmental Protection Agency (USEPA)) and/or maximum contaminant level (MCL, a legally enforceable drinking water standard set by the USEPA) for sulfate (SO4(2-)), chloride (Cl(-)), and fluoride (F(-)) in each decade. In both aquifers, however, >70% of observations exceeded the SMCL for total dissolved solids indicating high groundwater salinization. Water-level changes in Trinity aquifer also had significant negative impact on water quality. Hydrochemical facies in this region sequentially evolved from Ca-Mg-HCO3 and Ca-HCO3 in the fluvial sediments of the west to Na-SO4-Cl in the deltaic sediments to the east. Sequentially evolving hydrogeochemical facies and increasing salinization closely resembled regional groundwater flow pattern. Distinct spatial

  8. Rational allocation of water resources based on ecological groundwater levels:a case study in Jinghui Irrigation District in China

    Science.gov (United States)

    Li, H.; Zhou, W. B.; Dong, Q. G.; Liu, B. Y.; Ma, C.

    2016-08-01

    Aimed at the hydrogeological environmental problems caused by over-exploitation and unreasonable utilization of water resources in Jinghui Irrigation District, this paper discusses the ecological groundwater level of the study area and establishes a three-layer optimal allocation model of water resources based on the theory of large scale systems. Then, the genetic algorithm method was employed to optimize the model and obtain the optimal allocation of crop irrigation schedule and water resources under the condition of a 75% assurance rate. Finally, the numerical simulation model of the groundwater was applied to analyze the balance of the groundwater on the basis of the optimal allocation scheme. The results show that the upper limitation of the ecological groundwater in Jinghui Irrigation District ranged from 1.8m to 4.2m, while the lower limitation level ranged from 8m to 28m. By 2020, the condition of the groundwater imbalance that results from adopting the optimal allocation scheme will be much better than that caused by current water utilization scheme. With the exception of only a few areas, the groundwater level in most parts of Jinghui Irrigation District will not exceed the lower limitation of ecological groundwater level.

  9. 3-D VARIABLE PARAMETER NUMERICAL MODEL FOR EVALUATION OF THE PLANNED EXPLOITABLE GROUNDWATER RESOURCE IN REGIONAL UNCONSOLIDATED SEDIMENTS

    Institute of Scientific and Technical Information of China (English)

    LUO Zu-jiang; WANG Yan

    2012-01-01

    In order to correctly evaluate the exploitable groundwater resource in regional complex,thick Quaternary unconsolidated sediments,the whole Quaternary unconsolidated sediments are considered as a unified hydrogeological unit and a 3-D unsteady groundwater flow numerical model is adopted.Meanwhile,with the consideration of the dynamic changes of the porosity,the hydraulic conductivity and the specific storage with the groundwater level dropping during the exploitation process,an improved composite element seepage matrix adjustment method is applied to solve the unsteady flow problem of free surface.In order to evaluate the exploitable groundwater resource in Cangzhou,Hebei Province,the hydrogeological conceptual model of Cangzhou is generalized to establish,a 3-D variable parameter numerical model of Cangzhou.Based on the prediction of the present groundwater exploitation,and by adjusting the groundwater exploitation layout,the exploitable groundwater resource is predicted.The model enjoys features like good convergence,good stability and high precision.

  10. A little island with significant groundwater resources: hydrogeological and hydrogeochemical features of the Pianosa aquifer (Tuscan Archipelago, Italy)

    Science.gov (United States)

    Giannecchini, R.; Doveri, M.; Mussi, M.; Nicotra, I.; Puccinelli, A.

    2012-12-01

    The Pianosa Island is one of the seven islands of the Tuscan Archipelago, particularly known for its typical flat morphological structure. It is formed by Neogenic-Quaternary sedimentary rocks, mainly represented by superficial calcarenite and underlying marl and clayey marl. Despite the small extension of the island (just 10,2 km2 wide, coastal perimeter of approximately 18 km, maximum altitude of 29 m a.s.l.) and poor rainfall amount (the annual average is 480,7 mm in 1951-2002 period), the Pianosa aquifer is characterized by significant groundwater resources, which supported the presence of approximately 2,000 people at the end of Eighties. Nevertheless, the groundwater overexploitation and the land use (agricultural activity and cattle-breeding, associated to the local penal settlement activity) caused important sea-water intrusion and pollution phenomena. An improvement of such situation occurs since 1998, owing to the closing of the penal settlement and its activities. This pilot research intends to describe the hydrogeological and hydrogeochemical features of the Pianosa Island aquifer system and the groundwater quality several years after the penal settlement closing. The results of a multidisciplinary approach (hydrogeological, geochemical, isotopic) show that the groundwater recharge and circulation are substantially controlled by the hydro-structural conditions. The flat and permeable superficial calcarenite allows a high infiltration rate. The water table flow direction is generally W-E, in accordance with the dip direction of the stratigraphic contact between the calcarenite and the underlying impermeable marly-clayey rocks. However, the latter present conglomerate and sandstone intercalations, sometimes in contact (by angular unconformity) with the calcarenite, determining a general continuity in groundwater circulation, which is phreatic in the calcarenite, and confined in the conglomerate and sandstone horizons. A piezometric depression with values

  11. Simulation of groundwater and surface-water resources and evaluation of water-management alternatives for the Chamokane Creek basin, Stevens County, Washington

    Science.gov (United States)

    Ely, D. Matthew; Kahle, Sue C.

    2012-01-01

    A three-dimensional, transient numerical model of groundwater and surface-water flow was constructed for Chamokane Creek basin to better understand the groundwater-flow system and its relation to surface-water resources. The model described in this report can be used as a tool by water-management agencies and other stakeholders to quantitatively evaluate the effects of potential increases in groundwater pumping on groundwater and surface-water resources in the basin. The Chamokane Creek model was constructed using the U.S. Geological Survey (USGS) integrated model, GSFLOW. GSFLOW was developed to simulate coupled groundwater and surface-water resources. The model uses 1,000-foot grid cells that subdivide the model domain by 102 rows and 106 columns. Six hydrogeologic units in the model are represented using eight model layers. Daily precipitation and temperature were spatially distributed and subsequent groundwater recharge was computed within GSFLOW. Streamflows in Chamokane Creek and its major tributaries are simulated in the model by routing streamflow within a stream network that is coupled to the groundwater-flow system. Groundwater pumpage and surface-water diversions and returns specified in the model were derived from monthly and annual pumpage values previously estimated from another component of this study and new data reported by study partners. The model simulation period is water years 1980-2010 (October 1, 1979, to September 30, 2010), but the model was calibrated to the transient conditions for water years 1999-2010 (October 1, 1998, to September 30, 2010). Calibration was completed by using traditional trial-and-error methods and automated parameter-estimation techniques. The model adequately reproduces the measured time-series groundwater levels and daily streamflows. At well observation points, the mean difference between simulated and measured hydraulic heads is 7 feet with a root-mean-square error divided by the total difference in water levels

  12. Bibliography of groundwater resources of the glacial aquifer systems in Washington, Idaho, and northwestern Montana, 1905-2011

    Science.gov (United States)

    Kahle, Sue C.; Futornick, Zoe O.

    2012-01-01

    The U.S. Geological Survey Groundwater Resources Program is undertaking a series of regional groundwater availability studies to improve our understanding of groundwater availability in major aquifers across the Nation. One of the objectives of the Glacial Principal Aquifers study (proposed) is to provide information on the occurrence of groundwater in glacial aquifers in the United States, an area that includes parts of the northern continental States and much of Alaska. Toward this effort, a literature search was conducted to identify readily available documents that describe the occurrence of groundwater in glacial aquifers in the United States. This bibliography provides citations for documents, as well as codes indicating types of information available in each, for Washington, Idaho, and northwestern Montana—an area corresponding approximately to the southern extent of the Cordilleran ice sheet.

  13. Application of a spatially distributed water balance model for assessing surface water and groundwater resources in the Geba basin, Tigray, Ethiopia

    Science.gov (United States)

    Gebreyohannes, Tesfamichael; De Smedt, Florimond; Walraevens, Kristine; Gebresilassie, Solomon; Hussien, Abdelwasie; Hagos, Miruts; Amare, Kasa; Deckers, Jozef; Gebrehiwot, Kindeya

    2013-08-01

    The Geba basin is one of the most water-stressed areas of Ethiopia, with only a short rainy period from mid-June to mid-September. Because rainfall in this region has been consistently erratic in the last decades, both in time and space, rain-fed agriculture has become problematic. Hence, in order to supplement rain-fed agriculture by irrigation, a detailed understanding of local and regional surface water and groundwater resources is important. The main objective of this study is to assess the available water resources in the Geba basin using a spatially distributed water balance model (WetSpass). Relevant input data for the model is prepared in the form of digital maps using remote sensing images, GIS tools, FAO and NASA databases, field reconnaissance and processing of meteorological and hydrological observations. The model produces digital maps of long-term average, seasonal and annual surface runoff, evapotranspiration and groundwater recharge. Results of the model show that 76% of the precipitation in the basin is lost through evapotranspiration, 18% becomes surface runoff and only 6% recharges the groundwater system. Model predictions are verified against river flow observations and are shown to be reliable. Additional maps are derived of accumulated surface runoff, safe yield for groundwater abstraction and water deficit for crop growth. Comparison of existing reservoirs with the accumulated runoff map shows that many reservoirs have failed because their design capacity is much higher than the actual inflow. Comparison of the safe yield map with the crop water deficit map shows that in most areas groundwater can be safely abstracted to supplement the water deficit for crop growth during the wet summer season. However, in the dry winter season the crop water deficit is too high to be supplemented by groundwater abstraction in a sustainable way.

  14. Modelling the distribution of tritium in groundwater across South Africa to assess the vulnerability and sustainability of groundwater resources in response to climate change

    Science.gov (United States)

    van Rooyen, Jared; Miller, Jodie; Watson, Andrew; Butler, Mike

    2017-04-01

    Groundwater is critical for sustaining human populations, especially in semi-arid to arid areas, where surface water availability is low. Shallow groundwater is usually abstracted for this purpose because it is the easiest to access and assumed to be renewable and regularly recharged by precipitation. Renewable, regularly recharged groundwater is also called modern groundwater, ie groundwater that has recently been in contact with the atmosphere. Tritium can be used to determine whether or not a groundwater resource is modern because the half-life of tritium is only 12.36 years and tritium is dominantly produced in the upper atmosphere and not in the rock mass. For this reason, groundwater with detectable tritium activities likely has a residence age of less than 50 years. In this study, tritium activities in 277 boreholes distributed across South Africa were used to develop a national model for tritium activity in groundwater in order to establish the extent of modern groundwater across South Africa. The tritium model was combined with modelled depth to water using 3079 measured static water levels obtained from the National Groundwater Archive and validated against a separate set of 40 tritium activities along the west coast of South Africa. The model showed good agreement with the distribution of rainfall which has been previously documented across the globe (Gleeson et al., 2015), although the arid Karoo basin in south west South Africa shows higher than expected tritium levels given the very low regional precipitation levels. To assess the vulnerability of groundwater to degradation in quality and quantity, the tritium model was incorporated into a multi-criteria evaluation (MCE) model which incorporated other indicators of groundwater stress including mean annual precipitation, mean annual surface temperature, electrical conductivity (as a proxy for groundwater salinization), potential evaporation, population density and cultivated land usage. The MCE model

  15. Pleistocene paleo-groundwater as a pristine fresh water resource in southern Germany--evidence from stable and radiogenic isotopes.

    Science.gov (United States)

    van Geldern, Robert; Baier, Alfons; Subert, Hannah L; Kowol, Sigrid; Balk, Laura; Barth, Johannes A C

    2014-10-15

    Shallow groundwater aquifers are often influenced by anthropogenic contaminants or increased nutrient levels. In contrast, deeper aquifers hold potentially pristine paleo-waters that are not influenced by modern recharge. They thus represent important water resources, but their recharge history is often unknown. In this study groundwater from two aquifers in southern Germany were analyzed for their hydrogen and oxygen stable isotope compositions. One sampling campaign targeted the upper aquifer that is actively recharged by modern precipitation, whereas the second campaign sampled the confined, deep Benkersandstein aquifer. The groundwater samples from both aquifers were compared to the local meteoric water line to investigate sources and conditions of groundwater recharge. In addition, the deep groundwater was dated by tritium and radiocarbon analyses. Stable and radiogenic isotope data indicate that the deep-aquifer groundwater was not part of the hydrological water cycle in the recent human history. The results show that the groundwater is older than ~20,000 years and most likely originates from isotopically depleted melt waters of the Pleistocene ice age. Today, the use of this aquifer is strictly regulated to preserve the pristine water. Clear identification of such non-renewable paleo-waters by means of isotope geochemistry will help local water authorities to enact and justify measures for conservation of these valuable resources for future generations in the context of a sustainable water management.

  16. Quantifying the Impact of a Transboundary Streamflow Agreement on Groundwater Resources in the US High Plains Aquifer

    Science.gov (United States)

    Deines, J.; Hyndman, D. W.; Kendall, A. D.

    2015-12-01

    Many groundwater aquifers in important agricultural areas are exploited beyond their sustainable limits. Groundwater overuse can reduce streamflow across political boundaries, leading to transboundary management challenges. Although conflicts over transboundary water resources do arise, these conflicts can also prompt improved aquifer management. Portions of the Republican River Basin, which overlies the High Plains Aquifer in the central United States, have been under court-ordered groundwater restrictions to meet interstate streamflow requirements since 2004, following the 2002 Kansas v. Nebraska and Colorado Supreme Court case. We examined the impacts of these restrictions on groundwater levels, pumping volume, agricultural productivity, and streamflow in the Nebraska portion of the basin to assess how transboundary agreements can affect groundwater sustainability in agricultural systems. We synthesized available data for 1990-2014 to analyze trends before and after restrictions went into effect in 2004. After controlling for climate covariates, we found that restrictions reduced pumping volumes in the study area, resulting in increased streamflow across the Nebraska-Kansas border. Furthermore, restrictions appear to have reversed the declining trend in groundwater storage. Notably, this reversal contrasts with continuing decline in the unrestricted Kansas portion of the basin, suggesting the court-ordered restrictions have altered the sustainability trajectory of this region. The impacts of pumping restrictions on regional agricultural yields and productivity are examined. Our analysis of this system suggests that by setting external limits on resource use, enforceable transboundary water agreements can stimulate sustainable groundwater management and counter local incentives for overextraction.

  17. Evaluation of the sustainability of deep groundwater as an arsenic-safe resource in the Bengal Basin

    Science.gov (United States)

    Michaela, Holly A.; Voss, Clifford I.

    2008-01-01

    Tens of millions of people in the Bengal Basin region of Bangladesh and India drink groundwater containing unsafe concentrations of arsenic. This high-arsenic groundwater is produced from shallow (150 m where groundwater arsenic concentrations are nearly uniformly low, and many more wells are needed, however, the sustainability of deep, arsenic-safe groundwater has not been previously assessed. Deeper pumping could induce downward migration of dissolved arsenic, permanently destroying the deep resource. Here, it is shown, through quantitative, large-scale hydrogeologic analysis and simulation of the entire basin, that the deeper part of the aquifer system may provide a sustainable source of arsenic-safe water if its utilization is limited to domestic supply. Simulations provide two explanations for this result: deep domestic pumping only slightly perturbs the deep groundwater flow system, and substantial shallow pumping for irrigation forms a hydraulic barrier that protects deeper resources from shallow arsenic sources. Additional analysis indicates that this simple management approach could provide arsenic-safe drinking water to >90% of the arsenic-impacted region over a 1,000-year timescale. This insight may assist water-resources managers in alleviating one of the world's largest groundwater contamination problems.

  18. Evaluation of the sustainability of deep groundwater as an arsenic-safe resource in the Bengal Basin

    Science.gov (United States)

    Michael, H.A.; Voss, C.I.

    2008-01-01

    Tens of millions of people in the Bengal Basin region of Bangladesh and India drink groundwater containing unsafe concentrations of arsenic. This high-arsenic groundwater is produced from shallow (150 m where groundwater arsenic concentrations are nearly uniformly low, and many more wells are needed, however, the sustainability of deep, arsenic-safe ground-water has not been previously assessed. Deeper pumping could induce downward migration of dissolved arsenic, permanently destroying the deep resource. Here, it is shown, through quantitative, large-scale hydrogeologic analysis and simulation of the entire basin, that the deeper part of the aquifer system may provide a sustainable source of arsenic-safe water if its utilization is limited to domestic supply. Simulations provide two explanations for this result: deep domestic pumping only slightly perturbs the deep groundwater flow system, and substantial shallow pumping for irrigation forms a hydraulic barrier that protects deeper resources from shallow arsenic sources. Additional analysis indicates that this simple management approach could provide arsenic-safe drinking water to >90% of the arsenic-impacted region over a 1,000-year timescale. This insight may assist water-resources managers in alleviating one of the world's largest groundwater contamination problems. ?? 2008 by The National Academy of Sciences of the USA.

  19. Groundwater resource degradation in coastal plains: The example of the Cecina area (Tuscany - Central Italy)

    Energy Technology Data Exchange (ETDEWEB)

    Grassi, Sergio [Institute of Geosciences and Earth Resources, Via Moruzzi 1, I-56124 Pisa (Italy)], E-mail: grassi@igg.cnr.i; Cortecci, Gianni; Squarci, Paolo [Institute of Geosciences and Earth Resources, Via Moruzzi 1, I-56124 Pisa (Italy)

    2007-11-15

    The paper describes the degradation of the groundwater resources in the Cecina area, where seawater intrusion, B contamination and NO{sub 3} pollution are all affecting the heavily exploited Pleistocene aquifer. Over-pumping has brought water levels to about 0 m.a.s.l. as far as about 7 km from the shore line, thereby promoting the seawater intrusion. The intrusion, which is characterized by cation exchange phenomena and Ca-Cl type waters, enters the plain mostly through the shallower horizons. The saline front, which advanced from 0.5 to 1 km in 4 a, has by now reached the foot of the hills to the east of the town, where it is also affecting wells of the local aqueduct. Boron contamination, linked to past discharge of industrial waste transported downstream by the river, reached concentrations as high as 3.5 mg/L in the mid-1980s. Although a decreasing trend is now under way, B content is still close to 1 mg/L. The presence of high NO{sub 3}, which, together with the seawater intrusion, represents a major issue for groundwater management in the area, is linked to the widespread utilization of fertilizers. Nitrate concentration, which reaches a maximum of about 300 mg/L in the shallow aquifer horizons and then decreases rather regularly with depth, is strongly influenced by precipitation. However, irrigation also contributes significantly to transporting the NO{sub 3} contamination to depth, as clearly shown by {delta}{sup 18}O data. The severe decline in the quality of the groundwater resource in the Cecina area is further compounded by an overall decrease in water availability in the region of Tuscany, as evidenced by long-term monitoring of precipitation and fluvial discharge.

  20. Analyses of surface and groundwater flow characteristics of the Ljubljana moor and water resources vulnerability to climate and land use change and groundwater overdraft

    Science.gov (United States)

    Globevnik, Lidija; Bracic Zeleznik, Branka

    2016-04-01

    One of the biggest water resource of Slovenian capital is groundwater of Ljubljana moor (Ljubljansko barje) aquifer. Quantity and quality of groundwater in Ljubljana moor aquifer directly depend on precipitation, surface water and riparian ecosystems of the Moor and indirectly by groundwater recharge from higher-lying mountainous karstic areas of forests and grasslands. Maintaining high groundwater level of the Ljubljana moor not only sustain stable water balance of aquifer, but also its riparian and wetland character. It also inhibit larger subsidence of the terrain. The paper addresses the vulnerability of the Ljubljana moor water resources to climate and land use change and due to groundwater overdraft. The results should help in selecting suitable mitigation measures and management of the Ljubljana moor area. We analyze surface and groundwater flow characteristics of water recharge area of one water work on the Ljubljana moor (Brest) from the point of view of climate change, changes in land use and water pumping practices. The I\\vska River, a tributary to the Ljubljanica River, recharges the area in the gravel bar, which lies just below the hills. We use existing data of meteorological, hydrological and hydrogeological monitoring and simulate rainfall-runoff processes. We use a conceptual semi-distributed rainfall-runoff model HBV-Light and simulate hydrological characteristics of the Ljubljana Moor (groundwater level fluctuations and recharge, surface - groundwater interchange) with two hydrodynamic models, DHI MIKE FLOOD (surface flow, 2D simulation) and DHI MIKE SHE (groundwater flow). For a calibration of runoff model HBV Light and MIKE SHE we use measured daily discharge data of the river I\\vska (1970-2010) and groundwater level data along the river (2010-2013) respectively. In groundwater modelling, we include the data of water pumping. Daily precipitation and temperature for period 2020 - 2050 are from ESAMBLE project for two GCM climate scenarios. We

  1. Groundwater and geothermal resources of Eritrea with the emphasis on their chemical quality

    Science.gov (United States)

    Zerai, Habteab

    1996-05-01

    Available chemical analyses have been evaluated and a water quality map prepared using electrical conductivity values. The country has been divided into three water quality regions. The quality of each region is variously a combination of climate, geology, waste disposal and irrigation practices and salt water intrusion. Region 1 has the best water quality, though in the Asmara area the groundwater is polluted by nitrate (50-150 mg l -1 NO 3). The impact on the natural environment due to the salinity hazard created by high evapotranspiration and irrigation practices becomes more pronounced across Region 2 and reaches a peak in the Red Sea catchments (Region 3), where it is supplemented by saline intrusion and mineralized upflows. In this region, soil fertility has been greatly affected and the development of groundwater has been constrained. Fluoride concentrations of 7-17 mg l -1 are common in Regions 2 and 3 and some dental fluorosis has been noted. Upflows of thermal water (34-100°C) exist in the Red Sea coastal zone and provide a potential energy resource. Both these and the factors affecting water resource quality in general require careful investigation and conservation measures.

  2. Groundwater recharge: Accurately representing evapotranspiration

    CSIR Research Space (South Africa)

    Bugan, Richard DH

    2011-09-01

    Full Text Available Groundwater recharge is the basis for accurate estimation of groundwater resources, for determining the modes of water allocation and groundwater resource susceptibility to climate change. Accurate estimations of groundwater recharge with models...

  3. Artificial groundwater recharge as integral part of a water resources system in a humid environment

    Science.gov (United States)

    Kupfersberger, Hans; Stadler, Hermann

    2010-05-01

    managed aquifer recharge system have been evaluated. Among numerous results it could be shown that replacing the lawn by sand basins and operating them constantly during winter holds the largest potential to increase the infiltration volume. However, this is only an option for new to build structures since the current basin positions would lead to large direct losses of recharged groundwater into the river Mur. Adjusting the timing of infiltration and withdrawal based on subsurface travel time yields an increase of the pumped amount of about 11% given about the same extension the wells' capture zones. The overall costs of artificial groundwater recharge amount to 0,15 €/m³ excluding pumping and distribution costs compared to a water price of about 1,5 €/m³ charged to consumers. Currently, the implications of building a hydro power plant adjacent to the recharge site are evaluated emphasizing the need for innovative solutions given only limited land resources. On the basis of the projected impacts of climate change on the availability of surface water and groundwater in the South-Eastern alpine regions, the aquifers can act as a buffer system to help overcome the timely shift between supply and demand. Thus, also in predominantly humid regions artificial groundwater recharge represents a viable and sustainable solution to safeguard the supply of drinking water in the long term.

  4. [Groundwater].

    Science.gov (United States)

    González De Posada, Francisco

    2012-01-01

    From the perspective of Hydrogeology, the concept and an introductory general typology of groundwater are established. From the perspective of Geotechnical Engineering works, the physical and mathematical equations of the hydraulics of permeable materials, which are implemented, by electric analogical simulation, to two unique cases of global importance, are considered: the bailing during the construction of the dry dock of the "new shipyard of the Bahia de Cádiz" and the waterproofing of the "Hatillo dam" in the Dominican Republic. From a physical fundamental perspective, the theories which are the subset of "analogical physical theories of Fourier type transport" are related, among which the one constituted by the laws of Adolf Fick in physiology occupies a historic role of some relevance. And finally, as a philosophical abstraction of so much useful mathematical process, the one which is called "the Galilean principle of the mathematical design of the Nature" is dealt with.

  5. Effectiveness of airborne multispectral thermal data for karst groundwater resources recognition in coastal areas

    Science.gov (United States)

    Pignatti, Stefano; Fusilli, Lorenzo; Palombo, Angelo; Santini, Federico; Pascucci, Simone

    2013-04-01

    Currently the detection, use and management of groundwater in karst regions can be considered one of the most significant procedures for solving water scarcity problems during periods of low rainfall this because groundwater resources from karst aquifers play a key role in the water supply in karst areas worldwide [1]. In many countries of the Mediterranean area, where karst is widespread, groundwater resources are still underexploited, while surface waters are generally preferred [2]. Furthermore, carbonate aquifers constitute a crucial thermal water resource outside of volcanic areas, even if there is no detailed and reliable global assessment of thermal water resources. The composite hydrogeological characteristics of karst, particularly directions and zones of groundwater distribution, are not up till now adequately explained [3]. In view of the abovementioned reasons the present study aims at analyzing the detection capability of high spatial resolution thermal remote sensing of karst water resources in coastal areas in order to get useful information on the karst springs flow and on different characteristics of these environments. To this purpose MIVIS [4, 5] and TASI-600 [6] airborne multispectral thermal imagery (see sensors' characteristics in Table 1) acquired on two coastal areas of the Mediterranean area interested by karst activity, one located in Montenegro and one in Italy, were used. One study area is located in the Kotor Bay, a winding bay on the Adriatic Sea surrounded by high mountains in south-western Montenegro and characterized by many subaerial and submarine coastal springs related to deep karstic channels. The other study area is located in Santa Cesarea (Italy), encompassing coastal cold springs, the main local source of high quality water, and also a noticeable thermal groundwater outflow. The proposed study shows the preliminary results of the two airborne deployments on these areas. The preprocessing of the multispectral thermal imagery

  6. Multi-modeling assessment of recent changes in groundwater resource: application to the semi-arid Haouz plain (Central Morocco)

    Science.gov (United States)

    Fakir, Younes; Brahim, Berjamy; Page Michel, Le; Fathallah, Sghrer; Houda, Nassah; Lionel, Jarlan; Raki Salah, Er; Vincent, Simonneaux; Said, Khabba

    2015-04-01

    The Haouz plain (6000 km2) is a part of the Tensift basin located in the Central Morocco. The plain has a semi-arid climate (250 mm/y of rainfall) and is bordered in the south by the High-Atlas mountains. Because the plain is highly anthropized, the water resources face heavy demands from various competing sectors, including agriculture (over than 273000 ha of irrigated areas), water supply for more than 2 million inhabitants and about 2 millions of tourists annually. Consequently the groundwater is being depleted on a large area of the plain, with problems of water scarcity which pose serious threats to water supplies and to sustainable development. The groundwater in the Haouz plain was modeled previously by MODFLOW (USGS groundwater numerical modeling) with annual time steps. In the present study a multi-modeling approach is applied. The aim is to enhance the evaluation of the groundwater pumping for irrigation, one of the most difficult data to estimate, and to improve the water balance assessment. In this purpose, two other models were added: SAMIR (Satellite Estimation of Agricultural Water Demand) and WEAP (integrated water resources planning). The three models are implemented at a monthly time step and calibrated over the 2001-2011 period, corresponding to 120 time steps. This multi-modeling allows assessing the evolution of water resources both in time and space. The results show deep changes during the last years which affect generally the water resources and groundwater particularly. These changes are induced by a remarkable urbanism development, succession of droughts, intensive agriculture activities and weak management of irrigation and water resources. Some indicators of these changes are as follow: (i) the groundwater table decrease varies between 1 to 3m/year, (ii) the groundwater depletion during the last ten year is equivalent to 50% of the lost reserves during 40 years, (iii) the annual groundwater deficit is about 100 hm3, (iv) the renewable

  7. Effects of 3-D Visualization of Groundwater Modeling for Water Resource Decision Making

    Science.gov (United States)

    Block, J. L.; Arrowsmith, R.

    2006-12-01

    The rise of 3-D visualization hardware and software technology provides important opportunities to advance scientific and policy research. Although the petroleum industry has used immersive 3-D technology since the early 1990's for the visualization of geologic data among experts, there has been little use of this technology for decision making. The Decision Theater at ASU is a new facility using immersive visualization technology designed to combine scientific research at the university with policy decision making in the community. I document a case study in the use of 3-D immersive technology for water resource management in Arizona. Since the turn of the 20th century, natural hydrologic processes in the greater Phoenix region (Salt River Valley) have been shut down via the construction of dams, canals, wells, water treatment plants, and recharge facilities. Water from rivers that once naturally recharged the groundwater aquifer have thus been diverted while continuing groundwater outflow from wells has drawn the aquifer down hundreds of feet. MODFLOW is used to simulate groundwater response to the different water management decisions which impact the artificial and natural inflow and outflow. The East Valley Water Forum, a partnership of water providers east of Phoenix, used the 3-D capabilities of the Decision Theater to build visualizations of the East Salt River Valley groundwater system based on MODFLOW outputs to aid the design of a regional groundwater management plan. The resulting visualizations are now being integrated into policy decisions about long term water management. I address challenges in visualizing scientific information for policy making and highlight the roles of policy actors, specifically geologists, computer scientists, and political decision makers, involved in designing the visualizations. The results show that policy actors respond differently to the 3-D visualization techniques based on their experience, background, and objectives

  8. Desalination as Groundwater Conservation: The Cost of Protecting Cultural and Environmental Resources in Chile's Region II

    Science.gov (United States)

    Edwards, E. C.; Cristi, O.; Libecap, G. D.

    2012-12-01

    There is a substantial body of evidence that groundwater overdraft is occurring worldwide. Economists argue that the cause of this overdraft is the open-access nature of the resource, which results in a "tragedy of the commons." Sustainable water management requires that some institution control the resource to limit this overdraft by reducing water extraction. This reduction creates scarcity and requires a method of rationing. The economically efficient outcome occurs when the lowest value uses of water are eliminated. This allocation, though, may have undesirable social consequences, such as the loss of small-scale farming, and political ramifications that make such an allocation unpopular to implement. This paper explores the economic cost of leaving water in low-value uses. The policy we explore is a moratorium on voluntary water sales to mining firms to protect the groundwater resource in northern Chile. This policy has accelerated the use of expensive desalinated water, whose cost is primarily driven by its heavy use of carbon-based electricity. Chile has a strong system of water property rights that economists argue ration water in a way that leads to the efficient allocation through water markets. This paper first explores the potential inefficiency of a water market when groundwater and surface water are linked, as well as when different users vary in their intensity of use. This theoretical background provides a framework for determining the economically efficient allocation of water and the losses associated with the moratorium in northern Chile. The policy does protect some environmental and cultural public goods, which potentially offset some or all of this cost. We provide a perspective on the magnitude of these public goods but do not attempt to value them explicitly. Instead, we demonstrate what their value must be so that the moratorium policy has a cost-to-benefit ratio of one. While the estimate of lost income from inefficiency is the main focus

  9. Maryland Ground-Water Observation Well Network, 2001

    Data.gov (United States)

    U.S. Geological Survey, Department of the Interior — MDNET is a point coverage that represents the locations and names of a network of observation wells for the State of Maryland. Additional information on water...

  10. Pleistocene paleo-groundwater as a pristine fresh water resource in southern Germany – evidence from stable and radiogenic isotopes

    Energy Technology Data Exchange (ETDEWEB)

    Geldern, Robert van, E-mail: robert.van.geldern@fau.de [Friedrich-Alexander-University Erlangen-Nuremberg (FAU), Department of Geography and Geosciences, GeoZentrum Nordbayern, Schlossgarten 5, 91054 Erlangen (Germany); Baier, Alfons; Subert, Hannah L. [Friedrich-Alexander-University Erlangen-Nuremberg (FAU), Department of Geography and Geosciences, GeoZentrum Nordbayern, Schlossgarten 5, 91054 Erlangen (Germany); Kowol, Sigrid [Erlanger Stadtwerke AG, Äußere Brucker Str. 33, 91052 Erlangen (Germany); Balk, Laura; Barth, Johannes A.C. [Friedrich-Alexander-University Erlangen-Nuremberg (FAU), Department of Geography and Geosciences, GeoZentrum Nordbayern, Schlossgarten 5, 91054 Erlangen (Germany)

    2014-10-15

    Shallow groundwater aquifers are often influenced by anthropogenic contaminants or increased nutrient levels. In contrast, deeper aquifers hold potentially pristine paleo-waters that are not influenced by modern recharge. They thus represent important water resources, but their recharge history is often unknown. In this study groundwater from two aquifers in southern Germany were analyzed for their hydrogen and oxygen stable isotope compositions. One sampling campaign targeted the upper aquifer that is actively recharged by modern precipitation, whereas the second campaign sampled the confined, deep Benkersandstein aquifer. The groundwater samples from both aquifers were compared to the local meteoric water line to investigate sources and conditions of groundwater recharge. In addition, the deep groundwater was dated by tritium and radiocarbon analyses. Stable and radiogenic isotope data indicate that the deep-aquifer groundwater was not part of the hydrological water cycle in the recent human history. The results show that the groundwater is older than ∼20,000 years and most likely originates from isotopically depleted melt waters of the Pleistocene ice age. Today, the use of this aquifer is strictly regulated to preserve the pristine water. Clear identification of such non-renewable paleo-waters by means of isotope geochemistry will help local water authorities to enact and justify measures for conservation of these valuable resources for future generations in the context of a sustainable water management. - Highlights: • Groundwater from deep aquifer identified as paleo-water with age over 20,000 years. • Low stable isotope values indicate recharge during Pleistocene. • Shallow aquifer mirrors stable isotope signature of average modern precipitation. • Identification of non-renewable paleo-waters enhance sustainable water management. • Strict protection measures of authorities justified by isotope geochemistry.

  11. Land Subsidence and Groundwater Resources Investigations with the Use of D-InSAR, Numerical Modeling, and Field Data in the Toluca Valley, Mexico

    Science.gov (United States)

    Calderhead, A. I.; Martel, R.; Rivera, A.; Garfias, J.; Therrien, R.

    2008-12-01

    In the Toluca Valley, Mexico, urban and industrial growth have resulted in groundwater pumping exceeding recharge. Currently, there is a significant water budget deficit within the basin primarily due to groundwater pumping, and the loss is increasing with time. The stresses on the aquifer have caused significant changes on the water flow patterns, a reversal in the direction of hydraulic gradients, the disappearance of artesian springs and wetlands and noticeable land subsidence within the basin. The focus of this study is the investigation of water resources and land subsidence with the use of Differential Synthetic Aperture Radar Interferometry (D-InSAR), numerical modeling, and field data. The study is divided into two parts: 1) investigation of groundwater depletion in the Toluca Valley; and 2) assessment of land subsidence in the Toluca Valley. A spatially variable recharge model based on the Hydrologic Evaluation of Landfill Performance (HELP) numerical model examines the recharge; pumping estimates are based on a recent census and differences in piezometric surfaces. Currently there is a net loss (recharge - pumping) of over 150 million cubic meters per year of groundwater within the Toluca Basin aquifers. We examine various changes in regional flow patterns, and groundwater levels decline throughout the valley. At the current rate of consumption, groundwater resources are not sustainable for the population of the valley. Directly related to the decrease in groundwater levels is the occurrence of land subsidence. Regional land subsidence of the Toluca Valley is observed with the use of SAR images obtained from the European Space agency's ERS-1, ERS-2 and ENVISAT Satellites and the Canadian Space Agency's RADARSAT-1 satellite. Data from years 1996 to 2008 are used to locate and quantify the subsidence; with subsidence rates reaching more than 15 cm/year. Results from the different sensors are also compared. The findings are verified with in

  12. Optimizing conjunctive use of surface water and groundwater resources with stochastic dynamic programming

    DEFF Research Database (Denmark)

    Davidsen, Claus; Liu, Suxia; Mo, Xinguo

    2014-01-01

    costs. As in traditional SDP approaches, one step-ahead sub-problems are solved to find the optimal management at any time knowing the inflow scenario and reservoir/aquifer storage levels. These non-linear sub-problems are solved using a genetic algorithm (GA) that minimizes the sum of the immediate......, reservoir states, and inflow scenarios are used as future costs to drive a forward moving simulation under uncertain water availability. The use of a GA to solve the sub-problems is computationally more costly than a traditional SDP approach with linearly interpolated future costs. However, in a two....... A stochastic dynamic programming (SDP) approach is used to minimize the basin-wide total costs arising from water allocations and water curtailments. Dynamic allocation problems with inclusion of groundwater resources proved to be more complex to solve with SDP than pure surface water allocation problems due...

  13. Studies on Resource Management of Sanjiang Plain Groundwater with the Analytical Finite Method Based on Square Grid

    Institute of Scientific and Technical Information of China (English)

    REN Yongtai; DENG Hualing; XU Dan

    2006-01-01

    This article established groundwater flows differential equation mathematical model of Sanjiang Plain on the hydrology theory foundation, and used the analysis finite element method to liner change the differential equation into the large-scale system of linear equations. It took linear equations as a part of constraint conditions of the optimized model, carried on the groundwater flow status equation and the optimized model the coupling, and carries on the solution with the Lingo software. The results indicated that this local shallow layer groundwater resources were rich and have the big development potential. But recent years water resources disposition was unreasonable and ground water mining quantity was oversized, these caused the region water flux to assume the drop tendency.

  14. Cooperative institutions for sustainable common pool resource management: Application to groundwater

    Science.gov (United States)

    Madani, Kaveh; Dinar, Ariel

    2012-09-01

    Beneficiaries of common pool resources (CPRs) may select available noncooperative and regulatory exogenous institutions for managing the resource, as well as cooperative management institutions. All these institutions may increase the long-term gains, prolong the life of the resource, and help to escape the tragedy of the commons trap. Cooperative game theory approaches can serve as the backbone of cooperative CPR management institutions. This paper formulates and applies several commonly used cooperative game theoretic solution concepts, namely, the core, Nash-Harsanyi, Shapley, and nucleolus. Through a numerical groundwater example, we show how CPR users can share the gains obtained from cooperation in a fair and efficient manner based on these cooperative solution concepts (management institutions). Although, based on their fairness rationales, various cooperative management institutions may suggest different allocations that are potentially acceptable to the users, these allocation solutions may not be stable as some users may find them unfair. This paper discusses how different methods, such as application of the plurality rule and power index, stability index, and propensity to disrupt concepts, can help identify the most stable and likely solutions for enforcing cooperation among the CPR beneficiaries. Furthermore, how the noncooperative managerial characteristics of the CPR users can affect the stability and acceptability of the different cooperative CPR management institutions is discussed, providing valuable policy insights for cooperative CPR management at community levels.

  15. Vulnerability Assessment of Groundwater Resources by Nutrient Source Apportionment to Individual Groundwater Wells: A Case Study in North Carolina

    Science.gov (United States)

    Ayub, R.; Obenour, D. R.; Keyworth, A. J.; Genereux, D. P.; Mahinthakumar, K.

    2016-12-01

    Groundwater contamination by nutrients (nitrogen and phosphorus) is a major concern in water table aquifers that underlie agricultural areas in the mid-Atlantic Coastal Plain of the United States. High nutrient concentrations leaching into shallow groundwater can lead to human health problems and eutrophication of receiving surface waters. Liquid manure from concentrated animal feeding operations (CAFOs) stored in open-air lagoons and applied to spray fields can be a significant source of nutrients to groundwater, along with septic waste. In this study, we developed a model-based methodology for source apportionment and vulnerability assessment using sparse groundwater quality sampling measurements for Duplin County, North Carolina (NC), obtained by the NC Department of Environmental Quality (NC DEQ). This model provides information relevant to management by estimating the nutrient transport through the aquifer from different sources and addressing the uncertainty of nutrient contaminant propagation. First, the zones of influence (dependent on nutrient pathways) for individual groundwater monitoring wells were identified using a two-dimensional vertically averaged groundwater flow and transport model incorporating geologic uncertainty for the surficial aquifer system. A multiple linear regression approach is then applied to estimate the contribution weights for different nutrient source types using the nutrient measurements from monitoring wells and the potential sources within each zone of influence. Using the source contribution weights and their uncertainty, a probabilistic vulnerability assessment of the study area due to nutrient contamination is performed. Knowledge of the contribution of different nutrient sources to contamination at receptor locations (e.g., private wells, municipal wells, stream beds etc.) will be helpful in planning and implementation of appropriate mitigation measures.

  16. Water Quality Assessment of Groundwater Resources in Qaleeh Shahin Plain Based on Cd and HEI

    Directory of Open Access Journals (Sweden)

    Yari A.R.

    2016-09-01

    Full Text Available Abstract Aims: The chemical elements in water resources, especially groundwater, can affect the water consumption purposes. The aim of this study was to evaluate the status of the overall pollution level of ground water of Qaleeh Shahin plain with respect to heavy metals by Cd and HEI methods. Instrument & Methods: This cross-sectional semi-experimental study was conducted in Sarpol-e Zahab township in Kermanshah Province, west of Iran. For this purpose, 20 groundwater wells were chosen randomly. The samples were filtered (0.45μm, stored in polyethylene bottles and were acidified at a pH lower than 2 by adding concentrated HNO3 in order to avoid metal adsorption onto the inner bottle walls. Element concentrations were determined using ICP-OES. The correlation between the metals in the different seasons, between the indices values and concentration of metals and between different indices values was assessed by Pearson’s correlation coefficient. Findings: There were no significant correlations between the concentrations of the elements in 2 seasons except between As and Cd in winter (r=0.544; p<0.05. Only the concentration of Pb had significant correlations with Cd (r=0.937; p=0.0001 and HEI (r=0.997; p=0.0001 values in winter and with Cd (r=0.997; p=0.0001 and HEI (r=0.810; p=0.0001 values in summer, which indicated Pb as the main contributory pollutant. The correlation between Cd and HEI was significant in winter (r=0.943; p=0.0001 and was significant in summer (r=0.818; p=0.0001. Conclusion: The water resources of Qaleeh Shahin plain, Kermanshah Province, Iran, are not polluted by heavy metals and are suitable for drinking.

  17. Conceptual models and sustainable groundwater resource indicators as transfer tools to stakeholders of the Lake Champlain transboundary aquifer

    Science.gov (United States)

    Lefebvre, René; Rivard, Christine; Carrier, Marc-André; Parent, Michel; Laurencelle, Marc; Beaudry, Châtelaine; Martin, Alex; Bleser, Joshua; Lavoie, Roxane; Bourque, Édith; Ouellet, Michel

    2016-04-01

    Regional aquifer assessments produce a wealth of scientific and technical information that is essential for the sound management of groundwater resources. However, regional water stakeholders are not generally groundwater specialists and cannot be expected to readily handle specialized hydrogeological maps and data. Without efficient information transfer, groundwater resources cannot be adequately considered in water governance by watershed organizations and in land-use planning by regional municipalities. This presentation provides an overview of the efforts undertaken to transfer information as part of a four-year regional aquifer assessment in the transboundary Canada-USA Champlain Lake watershed, with an emphasis on the southern Quebec part. This project was part of both the provincial aquifer assessment program (Programme d'acquisition des connaissances sur les eaux souterraines, PACES) of the Quebec Environment Ministry and the National inventory of regional key aquifers of Natural Resources Canada. In Quebec, the study area extends over 9 000 km2 and includes three major watersheds and 106 municipalities with 792 000 inhabitants. Five distinct hydrogeological contexts were defined based on bedrock geology and hydrogeological conditions: St. Lawrence Lowlands (North and South), Appalachian Piedmont, Appalachian Uplands, and Monteregian Hills. Extensive fieldwork filled knowledge and spatial data gaps identified during the compilation of existing data. To illustrate hydrogeological contexts, two conceptual models of different areas were developed. These conceptual models reflect three aspects of aquifer conditions: geological context, groundwater dynamics and groundwater quality. The first representation of the conceptual model presents the geological context including typical surficial geology units as well as major bedrock geology units (including faults and dykes). The second representation shows schematic groundwater flow paths, relative well yields of

  18. Geology and ground-water resources in the Zebulon area, Georgia

    Science.gov (United States)

    Chapman, M.J.; Milby, B.J.; Peck, M.F.

    1993-01-01

    The current (1991) surface-water source of drinking-water supply for the city of Zebulon, Pike County, Georgia, no longer provides an adequate water supply and periodically does not meet water-quality standards. The hydrogeology of crystalline rocks in the Zebulon area was evaluated to assess the potential of ground-water resources as a supplemental or alternative source of water to present surface-water supplies. As part of the ground-water resource evaluation, well location and construction data were compiled, a geologic map was constructed, and ground water was sampled and analyzed. Three mappable geologic units delineated during this study provide a basic understanding of hydrogeologic settings in the Zebulon area. Rock types include a variety of aluminosilicate schists, granitic rocks, amphibolites/honblende gneisses, and gondites. Several geologic features that may enhance ground-water availability were identified in the study area. These features include contacts between contrasting rock types, where a high degree of differential weathering has occurred, and well-developed structural features, such as foliation and jointing are present. High-yielding wells (greater than 25 gallons per minute) and low-yielding wells (less than one gallon per minute) were located in all three geologic units in a variety of topographic settings. Well yields range from less than one gallon per minute to 250 gallons per minute. The variable total depths and wide ranges of casing depths of the high-yielding wells are indicative of variations in depths to water-bearing zones and regolith thicknesses, respectively. The depth of water-bearing zones is highly variable, even on a local scale. Analyses of ground-water samples indicate that the distribution of iron concentration is as variable as well yield in the study area and does not seem to be related to a particular rock type. Iron concentrations in ground-water samples ranged from 0.02 to 5.3 milligrams per liter. Both iron

  19. Ground-water resources of southern Tangipahoa Parish and adjacent areas, Louisiana

    Science.gov (United States)

    Rapp, T.R.

    1994-01-01

    Groundwater resources in southern Tangipahoa Parish and adjacent areas were studied to determine their potential for development as an alternative to the Mississippi River as a water-supply source for Jefferson Parish. Eight major aquifers consisting of thick sand units that underlie the study area are, in descending order: (1) shallow, (2) upper Ponchatoula, (3) lower Ponchatoula, (4) Abita, (5) Covington, (6) Tchefuncta, (7) Hammond, and (8) Amite. A fault zone, referred to as the Baton Rouge fault, crosses southern Tangipahoa Parish. Analyses of geophysical logs indicated that the deep aquifers south of the fault zone had been displaced from 350 to 400 feet, and that the deeper aquifers were not in hydraulic connection with the flow system north of the fault. The groundwater resources of southeastern Louisiana are immense and the quality of groundwater in Tangipahoa Parish is suitable for most uses. The quality of water in these aquifers generally meets the U.S. Environmental Protection Agency's standards for public supply. The hydrologic system underlying Tangipahoa Parish and adjacent areas in 1990 supplied about 19 Mgal/d of water that was suitable for public supply. However, substantial increases in pumping from the aquifer system would result in renewed water-level declines throughout the hydrologic system until a new equilibrium is established. A test we11 in southern Tangipahoa Parish, penetrated all eight aquifers. Total thickness of freshwater sand beds penetrated by the 3003-ft test hole was more than 1900 ft. Resistivity values from an electric log of the test typically averaged 200 ohm-meters, which indicates that the water has low dissolved-solids and chloride concentrations. An analysis of the Abita aquifer at Ruddock in St. John the Baptist Parish, for two of three hypothetical well fields, indicated that for a hypothetical we11 field with a pumping rate of 112 Mgal/d, the freshwater/saltwater interface could arrive at the outer perimeter we11 in

  20. Quaternary Aquifer of the North China Plain-assessing and achieving groundwater resource sustainability

    Science.gov (United States)

    Foster, Stephen; Garduno, Hector; Evans, Richard; Olson, Doug; Tian, Yuan; Zhang, Weizhen; Han, Zaisheng

    The Quaternary Aquifer of the North China Plain is one of the world's largest aquifer systems and supports an enormous exploitation of groundwater, which has reaped large socio-economic benefits in terms of grain production, farming employment and rural poverty alleviation, together with urban and industrial water-supply provision. Both population and economic activity have grown markedly in the past 25 years. Much of this has been heavily dependent upon groundwater resource development, which has encountered increasing difficulties in recent years primarily as a result of aquifer depletion and related phenomena. This paper focuses upon the hydrogeologic and socio-economic diagnosis of these groundwater resource issues, and identifies strategies to improve groundwater resource sustainability. L'aquifère Quaternaire de la Plaine du Nord de la Chine est l'un des plus grands systèmes aquifères du monde; il permet une exploitation énorme d'eau souterraine, qui a permis des très importants bénéfices socio-économiques en terme de production de céréales, d'emplois ruraux et de réduction de la pauvreté rurale, en même temps que l'approvisionnement en eau potable et pour l'industrie. La population comme l'activité économique ont remarquablement augmenté au cours de ces 25 dernières années. Elles ont été sous la forte dépendance du développement de la ressource en eau souterraine, qui a rencontré des difficultés croissantes ces dernières années, du fait du rabattement de l'aquifère et des phénomènes associés. Cet article est consacré aux diagnostiques hydrogéologique et socio-économique des retombées de cette ressource en eau souterraine; il identifie les stratégies pour améliorer la pérennité des ressources en eau souterraine. El acuífero cuaternario de la Llanura Septentrional de China es uno de los mayores sistemas acuíferos del mundo y soporta una enorme explotación de su agua subterránea, las cuales han originado grandes

  1. Chemical considerations for an updated National assessment of brackish groundwater resources

    Science.gov (United States)

    McMahon, Peter B.; Bohlke, John Karl; Dahm, Katharine; Parkhurst, David L.; Anning, David W.; Stanton, Jennifer S.

    2016-01-01

    Brackish groundwater (BGW) is increasingly used for water supplies where fresh water is scarce, but the distribution and availability of such resources have not been characterized at the national scale in the United States since the 1960s. Apart from its distribution and accessibility, BGW usability is a function of the chemical requirements of the intended use, chemical characteristics of the resource, and treatment options to make the resource compatible with the use. Here, we discuss relations between these three chemical factors using national-scale examples and local case studies. In a preliminary compilation of BGW data in the United States, five water types accounted for the major-ion composition of 70% of samples. PHREEQC calculations indicate that 57–77% of samples were oversaturated with respect to barite, calcite, or chalcedony. In the study, 5–14% of samples had concentrations of arsenic, fluoride, nitrate, or uranium that exceeded drinking-water standards. In case studies of the potential use of BGW for drinking water, irrigation, and hydraulic fracturing, PHREEQC simulations of a hypothetical treatment process resembling reverse osmosis (RO) showed that BGW had the potential to form various assemblages of mineral deposits (scale) during treatment that could adversely affect RO membranes. Speciation calculations showed that most boron in the irrigation example occurred as boric acid, which has relatively low removal efficiency by RO. Results of this preliminary study indicate that effective national or regional assessments of BGW resources should include geochemical characterizations that are guided in part by specific use and treatment requirements.

  2. Chemical Considerations for an Updated National Assessment of Brackish Groundwater Resources.

    Science.gov (United States)

    McMahon, P B; Böhlke, J K; Dahm, K G; Parkhurst, D L; Anning, D W; Stanton, J S

    2016-07-01

    Brackish groundwater (BGW) is increasingly used for water supplies where fresh water is scarce, but the distribution and availability of such resources have not been characterized at the national scale in the United States since the 1960s. Apart from its distribution and accessibility, BGW usability is a function of the chemical requirements of the intended use, chemical characteristics of the resource, and treatment options to make the resource compatible with the use. Here, we discuss relations between these three chemical factors using national-scale examples and local case studies. In a preliminary compilation of BGW data in the United States, five water types accounted for the major-ion composition of 70% of samples. PHREEQC calculations indicate that 57-77% of samples were oversaturated with respect to barite, calcite, or chalcedony. In the study, 5-14% of samples had concentrations of arsenic, fluoride, nitrate, or uranium that exceeded drinking-water standards. In case studies of the potential use of BGW for drinking water, irrigation, and hydraulic fracturing, PHREEQC simulations of a hypothetical treatment process resembling reverse osmosis (RO) showed that BGW had the potential to form various assemblages of mineral deposits (scale) during treatment that could adversely affect RO membranes. Speciation calculations showed that most boron in the irrigation example occurred as boric acid, which has relatively low removal efficiency by RO. Results of this preliminary study indicate that effective national or regional assessments of BGW resources should include geochemical characterizations that are guided in part by specific use and treatment requirements.

  3. Hydrochemical evolution within a large alluvial groundwater resource overlying a shallow coal seam gas reservoir.

    Science.gov (United States)

    Owen, Daniel D R; Cox, Malcolm E

    2015-08-01

    A combination of multivariate statistical techniques, simple hydrochemical mixing models and inverse geochemical modelling was used to investigate the major hydrochemical evolutionary pathways of a large alluvial aquifer, the upper Condamine River alluvium, south-east Queensland, Australia. Hydrochemical similarities between alluvium and sedimentary bedrock groundwater imply some mixing between alluvial and sedimentary bedrock aquifers, but spatial assessment showed that this was localised around outcrops of sedimentary bedrock in upstream areas. Within the alluvium, a distinct shift towards a low salinity Na-HCO3 water type and a brackish Na-HCO3-Cl water type was obvious in two separate locations. Both of these water types are unique to the alluvium, and inverse modelling shows that they can evolve via a combination of in situ alluvial processes, including diffuse recharge of rainfall or river water or the evolution of basalt-derived groundwater via gypsum dissolution plagioclase weathering, cation exchange and some carbonate precipitation/dissolution. The evolution of these water types is potentially influenced by overlying sodic alkaline soils, and often is associated with a source of sulfate. Evapotranspiration is the dominant salinization process in the alluvium and increases in calcium cations during salinization indicate that brackish Na-HCO3-Cl groundwater in the underlying Walloon Coal Measures are unlikely to have a major influence on salinization in the alluvium. The most saline water types observed were endemic to shallow zones of the alluvium where evapotranspiration is likely. Results demonstrate that a combination of multivariate statistics and inverse geochemical modelling can be successfully used to delineate hydrochemical pathways in complex hydrogeological settings where a range of environmental and anthropogenic factors may be influencing the evolution of water types with similar hydrochemical compositions.

  4. Recharge heterogeneity and high intensity rainfall events increase contamination risk for Mediterranean groundwater resources

    Science.gov (United States)

    Hartmann, Andreas; Jasechko, Scott; Gleeson, Tom; Wada, Yoshihide; Andreo, Bartolomé; Barberá, Juan Antonio; Brielmann, Heike; Charlier, Jean-Baptiste; Darling, George; Filippini, Maria; Garvelmann, Jakob; Goldscheider, Nico; Kralik, Martin; Kunstmann, Harald; Ladouche, Bernard; Lange, Jens; Mudarra, Matías; Francisco Martín, José; Rimmer, Alon; Sanchez, Damián; Stumpp, Christine; Wagener, Thorsten

    2017-04-01

    Karst develops through the dissolution of carbonate rock and results in pronounced spatiotemporal heterogeneity of hydrological processes. Karst groundwater in Europe is a major source of fresh water contributing up to half of the total drinking water supply in some countries like Austria or Slovenia. Previous work showed that karstic recharge processes enhance and alter the sensitivity of recharge to climate variability. The enhanced preferential flow from the surface to the aquifer may be followed by enhanced risk of groundwater contamination. In this study we assess the contamination risk of karst aquifers over Europe and the Mediterranean using simulated transit time distributions. Using a new type of semi-distributed model that considers the spatial heterogeneity of karst hydraulic properties, we were able to simulate karstic groundwater recharge including its heterogeneous spatiotemporal dynamics. The model is driven by gridded daily climate data from the Global Land Data Assimilation System (GLDAS). Transit time distributions are calculated using virtual tracer experiments. We evaluated our simulations by independent information on transit times derived from observed time series of water isotopes of >70 karst springs over Europe. The simulations indicate that, compared to humid, mountain and desert regions, the Mediterranean region shows a stronger risk of contamination in Europe because preferential flow processes are most pronounced given thin soil layers and the seasonal abundance of high intensity rainfall events in autumn and winter. Our modelling approach includes strong simplifications and its results cannot easily be generalized but it still highlights that the combined effects of variable climate and heterogeneous catchment properties constitute a strong risk on water quality.

  5. Geology and ground-water resources of Wichita and Greeley Counties, Kansas

    Science.gov (United States)

    Prescott, G.C.; Branch, J.R.; Wilson, W.W.

    1954-01-01

    This report describes the geography, geology, and ground-water resources of Wichita and Greeley counties in western Kansas. The area consists of a flat to gently rolling plain, which slopes eastward [at] about 15 feet per mile. A short reach of Ladder Creek (Beaver) is the only perennially flowing stream in the two counties. Ephemeral streams, which flow only during and after heavy rains, are White Woman and Sand Creeks and the western reach of Ladder Creek. The climate is semiarid, the normal annual precipitation being about 17 inches in Wichita County and 16 inches in Greeley County. Agriculture is the principal occupation in the area, and wheat is the most important crop. A considerable area is irrigated; sugar beets and sorghums are the principal irrigated crops.The outcropping rocks range in age from late Cretaceous to Recent; the Smoky Hill chalk member of the Niobrara formation, which is exposed along White Woman Creek in western Greeley County, is the oldest. The Niobrara is almost everywhere overlain by the Ogallala formation of Pliocene age. Generally the Ogallala is overlain by windblown silt of the Pleistocene Sanborn formation, but in places it is exposed along streams. The most recent deposits are dune sand and the alluvium along the streams. The Dakota formation, which is an important aquifer in parts of Kansas, is 300 to 450 feet beneath the Niobrara formation.The ground water that is available to wells in Wichita and Greeley counties is derived entirely from precipitation in the area or in areas immediately west and north. Ground water moves in a generally easterly direction with a gradient that varies inversely with the permeability of the water-bearing beds. The ground-water reservoir is recharged principally by precipitation within the area or within adjacent areas, Ground-water discharge takes place principally by pumping from wells, subsurface outflow, and evaporation and transpiration. Most of the domestic, stock, public, and irrigation

  6. Examination of groundwater flow scales and results of water balance observation in the regional hydrogeological study project field.

    Energy Technology Data Exchange (ETDEWEB)

    Miyahara, Tomoya; Inaba, Kaoru; Saegusa, Hiromitsu; Takeuchi, Shinji [Japan Nuclear Cycle Development Inst., Tono Geoscience Center, Toki, Gifu (Japan)

    2002-09-01

    The Tono Geoscience center has been continuing water balance observation since fiscal 1998, and examining groundwater recharge into the basement rock. This report analyzes water balance at seven catchments in the regional hydrogeological study project field, and the applicability of area precipitation, an important item of water balance analysis, is examined. The result of the examination is shown below. Values of groundwater recharge in the small-scale catchments, such as upstream and downstream of the Shobagawa, are influence by the local groundwater flow system. But, those in the Shobagawa catchment are influenced by the larger groundwater flow system. The plane distribution of groundwater recharge matches the result of the distribution of groundwater flow analysis. (author)

  7. Ground-water resources of the Laura area, Majuro Atoll, Marshall Islands

    Science.gov (United States)

    Hamlin, S.N.; Anthony, S.S.

    1987-01-01

    The water system that supplies the heavily populated Dalap-Uliga-Darrit (DUD) area of Majuro atoll, Marshall Island, relies almost entirely upon airstrip catchment of rain water. Droughts cause severe water supply problems and water rationing is required, even during periods of normal rainfall. The Laura area contains a substantial lens of fresh groundwater that could be developed for export to the DUD area 30 mi to the east. Study of the groundwater resource at Laura involved a survey of existing wells, installation of monitoring wells and test holes, compilation of continuous records of rainfall and water level fluctuations, and collection of water quality data. Test hole data permitted the definition of three geohydrologic units which correlate well with similar units in Bikini and Enewetak atolls. The units consist of two layers of unconsolidated reef and lagoon sediments resting on a dense, highly permeable limestone. The potable water zone, or freshwater nucleus, of the lens is contained mostly within the unconsolidated layers, which are much less permeable than the basal limestone. Recharge to the Laura freshwater lens is estimated to be 1.8 mil gal/day, based on an average annual rainfall of 140 in. Sustainable yield is estimated to be about 400,000 gal/day. Shallow skimming wells or infiltration galleries similar to those used on Kwajalein atoll would be appropriate to develop the freshwater lens. The impact of development on the lens can be determined by monitoring the salinity in developed water and in a network of monitor wells. (Author 's abstract)

  8. Groundwater Resources Potential in the Coastal Plain Sands Aquifers, Lagos, Nigeria

    Directory of Open Access Journals (Sweden)

    E.O. Longe

    2011-01-01

    Full Text Available The hydraulic properties of the aquifers located in the coastal plain sands, Lagos, Nigeria had been investigated. A review of both the theoretical and practical applications of pumping tests in groundwater resource evaluation for coastal plain sands aquifer was carried out. The main activities involved collation of information related to well logs, step-drawdown and constant rate pumping tests from existing database on borehole drilling in seven wells to an average depth of 100 m. Graphical methods based on Rorabaugh’s Hantush-Bierschenk’s analyses were used to determine the components of drawdown due to well and aquifer losses from the step-drawdown pumping tests. Conventional analytical methods based on non-equilibrium equation were used to assess the local hydraulic regime of the groundwater system using constant rate pumping tests data. Data from 11 controlled pumping tests in Shomolu area of Lagos metropolis were analyzed. The transmissivity values of the multi-layered aquifer system range between 345.6 and 2,332 m2/day while the storage coefficient values range between 2.8x10-4 and 4.5x10-4. Both results indicate confined aquifers of artesian conditions. The step-drawdown pumping tests results indicate that well losses constituted a significant component of drawdown in the pumped wells, a phenomenon due to poor well design, well development; and non-Darcian flow in the multi-layered aquifer. The pumping test results allowed for theoretical and practical prediction of aquifer and well yields in the study area.

  9. Numerical model to support the management of groundwater resources of a coastal karstic aquifer (southern Italy)

    Science.gov (United States)

    Polemio, Maurizio; Romanazzi, Andrea

    2013-04-01

    The main purpose of the research is to define management apporouches for a coastal karstic aquifer. The core of the tools uses numerical modelling, applied to groundwater resource of Salento (southern Italy) and criteria to reduce the quantitative and qualitative degradation risks. The computer codes selected for numerical groundwater modelling were MODFLOW and SEAWAT. The approach chosen was based on the concept of a equivalent homogeneous porous medium by which it is assumed that the real heterogeneous aquifer can be simulated as homogeneous porous media within cells or elements. The modelled aquifer portion extends for 2230 km2, and it was uniformly discretized into 97,200 cells, each one of 0.6 km2. Vertically, to allow a good lithological and hydrogeological discretization, the area was divided into 12 layers, from 214 to -350 m asl. Thickness and geometry of layers was defined on the basis of the aquifer conceptualisation based on the 3d knowledge of hydrogeological complexes. For the boundary conditions, inactive cells were used along the boundary with the rest of Murgia-Salento aquifer, as conceptual underground watershed due to the absence of flow. About the sea boundary was used CHD boundary cells (Constant Head Boundary). Additional boundary conditions were used for SEAWAT modelling, as initial concentration and constant concentration, in the latter case for cells shaping the coastline. A mean annual net rainfall (recharge) was calculated in each cell with a GIS elaboration, ranged from 68 to 343 mm, 173 mm an average. The recharge or infiltration was calculated using an infiltration coefficient (IC) (defined as infiltration/net rainfall ratio) for each hydrogeological complex, assuming values equal to 1 inside endorheic areas. The mean annual recharge was equal to 150 mm. The model was implemented using MODFLOW and SEAWAT codes in steady-state conditions to obtain a starting point for following transient scenarios, using piezometric data of thirties as

  10. Markov decision processes in natural resources management: observability and uncertainty

    Science.gov (United States)

    Williams, Byron K.

    2015-01-01

    The breadth and complexity of stochastic decision processes in natural resources presents a challenge to analysts who need to understand and use these approaches. The objective of this paper is to describe a class of decision processes that are germane to natural resources conservation and management, namely Markov decision processes, and to discuss applications and computing algorithms under different conditions of observability and uncertainty. A number of important similarities are developed in the framing and evaluation of different decision processes, which can be useful in their applications in natural resources management. The challenges attendant to partial observability are highlighted, and possible approaches for dealing with it are discussed.

  11. Assessment of climate change impacts on groundwater resources: the case study of Veneto and Friuli plain in Italy

    Science.gov (United States)

    Critto, Andrea; Pasini, Sara; Torresan, Silvia; Rizzi, Jonathan; Zabeo, Alex; Marcomini, Antonio

    2013-04-01

    Climate change will have different impacts on water resources and water-dependent services worldwide. In particular, climate-related risks for groundwater and related ecosystems pose great concern to scientists and water authorities involved in the protection of these valuable resources. Research is needed to better understand how climate change will impact groundwater resources in specific regions and places and to develop predictive tools for their sustainable management, copying with the envisaged effects of global climate change and the key principles of EU water policy. Within the European project Life+ TRUST (Tool for Regional-scale assessment of groundwater Storage improvement in adaptation to climaTe change), a Regional Risk Assessment (RRA) methodology was developed in order to identify impacts from climate change on groundwater and associated ecosystems (e.g. surface waters, agricultural areas, natural environments) and to rank areas and receptors at risk in the high and middle Veneto and Friuli Plain (Italy). Based on an integrated analysis of impacts, vulnerability and risks linked to climate change at the regional scale, a RRA framework complying with the Sources-Pathway-Receptor-Consequence (SPRC) approach was defined. Relevant impacts on groundwater and surface waters (i.e. groundwater level variations, changes in nitrate infiltration processes, changes in water availability for irrigation) were selected and analyzed through hazard scenario, exposure, susceptibility and risk assessment. The RRA methodology used hazard scenarios constructed through global and high resolution models simulations for the 2071-2100 period, according with IPCC A1B emission scenario in order to produce useful indications for future risk prioritization and to support the addressing of adaptation measures, primarily Managed Artificial Recharge (MAR) techniques. Relevant outcomes from the described RRA application highlighted that potential climate change impacts will occur

  12. Use and abuse of the urban groundwater resource: Implications for a new management strategy

    Science.gov (United States)

    Drangert, J.-O.; Cronin, A. A.

    Various human activities threaten the groundwater quality and resource under urban areas, and yet residents increasingly depend on it for their livelihood. The anticipated expansion of the world's urban population from 3 to 6 billion in the coming 50 years does not only pose a large water management threat but also provides an opportunity to conserve groundwater in a better way than up to now. The authors argue for a new way to manage urban activities in order to conserve the precious groundwater resource. The focus is on the quality of the discharged water after use in households. Restrictions on what is added to water while using it, e.g. detergents, excreta, paint residues, oils, and pharmaceuticals, are important to simplify the treatment and reuse of used water. Avoiding mixing different wastewater flows has the same positive effect. If increased volumes of wastewater can be treated and reused, the demand on the groundwater resource is reduced, as also occurs with demand management measures. Reduced discharge of polluted water to the environment from households and utilities also conserves the quality of groundwater and reduces sophisticated treatment costs. L'urbanisation conduit à une demande élevée et concentrée d'eau de qualité adéquate, accompagnée du rejet d'importants volumes correspondants d'eaux usées. La nourriture est importée dans les villes tandis que les micro-organismes et les nutriments provenant des excrétas humains sont rejetés dans les rivières, les lacs et aussi les eaux souterraines. De plus, une large gamme de biens de consommation est évacuée par les égouts. Les créances environnementales, c'est-à-dire l'appauvrissement des conditions environnementales qui demandera des apports humains et économiques pour la réhabilitation, sont habituelles dans toutes les villes, et pas seulement dans l'hémisphère sud, comme cela est indiqué dans le rapport sur l'alimentation en eau et la santé publique du monde (publié par l

  13. Models and statistical analysis of organic micropollutants in groundwater-based drinking water resources

    DEFF Research Database (Denmark)

    Malaguerra, Flavio

    are also employed to identify large-scale contamination processes by examining observations of contamination in drinking water wells in Zealand, Denmark. Results show that persistent compounds in surface water can leach into nearby pumping wells even if an impermeable clay layer overlies the well screen....... Thus aquitards may not provide adequate protection against contamination by micropollutants in surface water, as generally thought. Results also show that the fermentation of organic compounds and the sulphate concentration in groundwater govern the success of sequential reductive dechlorination......The access to safe drinking water is essential for the well being of the population. The spread of micropollutant contamination jeopardise many freshwater reservoirs, and is a serious threat for human health, especially because of its long-term effects. To asses the threat of contamination, models...

  14. Development of a Conductivity Sensor for Monitoring Groundwater Resources to Optimize Water Management in Smart City Environments.

    Science.gov (United States)

    Parra, Lorena; Sendra, Sandra; Lloret, Jaime; Bosch, Ignacio

    2015-08-26

    The main aim of smart cities is to achieve the sustainable use of resources. In order to make the correct use of resources, an accurate monitoring and management is needed. In some places, like underground aquifers, access for monitoring can be difficult, therefore the use of sensors can be a good solution. Groundwater is very important as a water resource. Just in the USA, aquifers represent the water source for 50% of the population. However, aquifers are endangered due to the contamination. One of the most important parameters to monitor in groundwater is the salinity, as high salinity levels indicate groundwater salinization. In this paper, we present a specific sensor for monitoring groundwater salinization. The sensor is able to measure the electric conductivity of water, which is directly related to the water salinization. The sensor, which is composed of two copper coils, measures the magnetic field alterations due to the presence of electric charges in the water. Different salinities of the water generate different alterations. Our sensor has undergone several tests in order to obtain a conductivity sensor with enough accuracy. First, several prototypes are tested and are compared with the purpose of choosing the best combination of coils. After the best prototype was selected, it was calibrated using up to 30 different samples. Our conductivity sensor presents an operational range from 0.585 mS/cm to 73.8 mS/cm, which is wide enough to cover the typical range of water salinities. With this work, we have demonstrated that it is feasible to measure water conductivity using solenoid coils and that this is a low cost application for groundwater monitoring.

  15. Groundwater resources of the East Mountain area, Bernalillo, Sandoval, Santa Fe, and Torrance Counties, New Mexico, 2005

    Science.gov (United States)

    Bartolino, James R.; Anderholm, Scott K.; Myers, Nathan C.

    2010-01-01

    The groundwater resources of about 400 square miles of the East Mountain area of Bernalillo, Sandoval, Santa Fe, and Torrance Counties in central New Mexico were evaluated by using groundwater levels and water-quality analyses, and updated geologic mapping. Substantial development in the study area (population increased by 11,000, or 50 percent, from 1990 through 2000) has raised concerns about the effects of growth on water resources. The last comprehensive examination of the water resources of the study area was done in 1980-this study examines a slightly different area and incorporates data collected in the intervening 25 years. The East Mountain area is geologically and hydrologically complex-in addition to the geologic units, such features as the Sandia Mountains, Tijeras and Gutierrez Faults, Tijeras syncline and anticline, and the Estancia Basin affect the movement, availability, and water quality of the groundwater system. The stratigraphic units were separated into eight hydrostratigraphic units, each having distinct hydraulic and chemical properties. Overall, the major hydrostratigraphic units are the Madera-Sandia and Abo-Yeso; however, other units are the primary source of supply in some areas. Despite the eight previously defined hydrostratigraphic units, water-level contours were drawn on the generalized regional potentiometric map assuming all hydrostratigraphic units are connected and function as a single aquifer system. Groundwater originates as infiltration of precipitation in upland areas (Sandia, Manzano, and Manzanita Mountains, and the Ortiz Porphyry Belt) and moves downgradient into the Tijeras Graben, Tijeras Canyon, San Pedro synclinorium, and the Hagan, Estancia, and Espanola Basins. The study area was divided into eight groundwater areas defined on the basis of geologic, hydrologic, and geochemical information-Tijeras Canyon, Cedar Crest, Tijeras Graben, Estancia Basin, San Pedro Creek, Ortiz Porphyry Belt, Hagan Basin, and Upper Sandia

  16. Groundwater development effects on different scale hydrogeological systems using head, hydrochemical and isotopic data and implications for water resources management: The Selva basin (NE Spain)

    Science.gov (United States)

    Folch, A.; Menció, A.; Puig, R.; Soler, A.; Mas-Pla, J.

    2011-06-01

    SummaryHydrogeological resources in regional, large-scale groundwater systems are conditioned by their specific geological setting, which defines their capacity to supply human demand and their potential to recover from human-induced stress factors such as water withdrawal. In this paper, the hydrogeology of a range-and-basin hydrogeological system is described, based on potentiometric, hydrochemical and isotopic data, in order to fulfill a twofold objective: to characterize the alteration brought about in the hydrogeological system by intensive groundwater withdrawal, where tectonic elements such as fault zones play a significant role in the flow behaviour, and to define groundwater hydrodynamics under current human pressures as a necessary step to achieve appropriate groundwater management. Hydraulic head data indicate the relationships between geological formations in the range areas and the sedimentary infill of the basin. In this set-up, fault zones and a fracture network have a direct effect on the recharge, and allow upward vertical flow from the basement to the sedimentary aquifers. Hydrochemical and isotopic data support this observation. The use of fluoride and nitrate as tracers for the contribution of deep and shallow flow systems provides a detailed portrait of the effects of pumping on the flow path distribution. Isotopic data depict seasonal trends in the water captured by wells. In this connection, we can differentiate between two distinct flow systems: a regional, large-scale, longer residence time system, originating in the surrounding ranges, and a local flow system constituted by infiltration in the lower areas of the basin. The two systems, with specific water qualities, contribute differently to the resources that are withdrawn, and their specific contributions, in the frame of the basin water budget, determine the potential for present sustainable water exploitation.

  17. Case studies for utilizing groundwater-source and low-enthalpy geothermal resources in Korea

    Science.gov (United States)

    Kim, K.-H.; Shin, J.; Lee, K.-K.; Lee, T. J.

    2012-04-01

    As one of the top 10 oil-consuming countries in the world, Korea recently has had a great interest in extending the ways to utilize renewable energy. In this regard, geothermal energy resource is attracting more concerns from both of the government and the research field. Korea has neither active volcanic sites nor areas with abnormally higher heat flow. In spite of these natural conditions, many efforts have been exerted to utilize geothermal energy. Here, we introduce two case studies of using groundwater-source geothermal energy with relatively low-enthalpy: One is a riverbank filtration facility, which has been using some of its riverbank filtrate water for the indoor air-conditioning. The other is the first EGS plant planning site, where a few fault-related artesian wells reaching 70C were discovered lately. Numerical simulations to predict the temperature evolution of the two sites, which is dominated by several hydrogeologic factors, were carried out and compared. Simulation of temperature profile of riverbank filtrate water using HydroGeoSphere shows that the primary factor in determining filtrate water temperature is the pumping rate. It also shows that maintaining the facility operation with present pumping rate for the next 30 years will not cause any significant change of water temperature. However, following the new plan of the facility to install additional 37 wells with 6 times higher pumping rate than the current rate might cause about 2C decrease in filtrate water temperature in 10 years after the extension. Simulation for the temperature evolution in a faulted geothermal reservoir in EGS planning site under the supposed injection-extraction operating conditions were carried out using TOUGH2. A MINC model including a hydraulic discontinuity, which reflected the analysis from several geophysical explorations, was generated. Temperature distribution calculated from the simulation shows a rise of relatively hot geothermal water along the fault plane

  18. A Groundwater Model to Assess Water Resource Impacts at the Imperial East Solar Energy Zone

    Energy Technology Data Exchange (ETDEWEB)

    Quinn, John [Argonne National Lab. (ANL), Argonne, IL (United States); Greer, Chris [Argonne National Lab. (ANL), Argonne, IL (United States); O' Connor, Ben L. [Argonne National Lab. (ANL), Argonne, IL (United States); Tompson, Andrew F.B. [Lawrence Livermore National Lab. (LLNL), Livermore, CA (United States)

    2013-12-01

    The purpose of this study is to develop a groundwater flow model to examine the influence of potential groundwater withdrawal to support the utility-scale solar energy development at the Imperial East Solar Energy Zone (SEZ) as a part of the Bureau of Land Management’s (BLM) solar energy program.

  19. A Groundwater Model to Assess Water Resource Impacts at the Brenda Solar Energy Zone

    Energy Technology Data Exchange (ETDEWEB)

    Quinn, John [Argonne National Lab. (ANL), Argonne, IL (United States); Carr, Adrianne E. [Argonne National Lab. (ANL), Argonne, IL (United States); Greer, Chris [Argonne National Lab. (ANL), Argonne, IL (United States); Bowen, Esther E. [Argonne National Lab. (ANL), Argonne, IL (United States)

    2013-12-01

    The purpose of this study is to develop a groundwater flow model to examine the influence of potential groundwater withdrawal to support utility-scale solar energy development at the Brenda Solar Energy Zone (SEZ), as a part of the Bureau of Land Management’s (BLM’s) Solar Energy Program.

  20. A new approach to calibrate steady groundwater flow models with time series of head observations

    Science.gov (United States)

    Obergfell, C.; Bakker, M.; Maas, C.

    2012-04-01

    We developed a new method to calibrate aquifer parameters of steady-state well field models using measured time series of head fluctuations. Our method is an alternative to standard pumping tests and is based on time series analysis using parametric impulse response functions. First, the pumping influence is isolated from the overall groundwater fluctuation observed at monitoring wells around the well field, and response functions are determined for each individual well. Time series parameters are optimized using a quasi-Newton algorithm. For one monitoring well, time series model parameters are also optimized by means of SCEM-UA, a Markov Chain Monte Carlo algorithm, as a control on the validity of the parameters obtained by the faster quasi-Newton method. Subsequently, the drawdown corresponding to an average yearly pumping rate is calculated from the response functions determined by time series analysis. The drawdown values estimated with acceptable confidence intervals are used as calibration targets of a steady groundwater flow model. A case study is presented of the drinking water supply well field of Waalwijk (Netherlands). In this case study, a uniform aquifer transmissivity is optimized together with the conductance of ditches in the vicinity of the well field. Groundwater recharge or boundary heads do not have to be entered, which eliminates two import sources of uncertainty. The method constitutes a cost-efficient alternative to pumping tests and allows the determination of pumping influences without changes in well field operation.

  1. Digitized generalized areas where surface-water resources likely or potentially are susceptible to groundwater withdrawals in adjacent valleys, Great Basin National Park area, Nevada

    Data.gov (United States)

    U.S. Geological Survey, Department of the Interior — Polygons delineate generalized areas in and around Great Basin National Park where surface-water resources likely or potentially are susceptible to groundwater...

  2. An approach to managing cumulative effects to groundwater resources in the Alberta oil sands

    Energy Technology Data Exchange (ETDEWEB)

    Fennell, J.; Forrest, Francine [WorleyParsons Canada, Infrastructure and Environment (Canada); Klebek, Margaret [Alberta Environment, Clean Energy Policy Branch (Canada)

    2011-07-01

    In the Athabasca region of Northern Alberta, oil sands activity has raised many concerns over how mining and extracting processes might affect groundwater quality and quantity. The groundwater management framework was developed by Alberta Environment to address these concerns by identifying and managing the potential environmental effects of oil sands activity on groundwater in a science-based manner. This paper develops the framework using risk identification and performance monitoring. The decision-making approach was conducted using decision support tools such as modeling, monitoring and management. Results showed the complexity and variability of groundwater conditions in the Athabasca region and pointed out that knowledge in this area is still developing. This paper presented how the groundwater management framework was developed and pointed out that it will have to be updated as new information arrives.

  3. Review: Moisture loading—the hidden information in groundwater observation well records

    Science.gov (United States)

    van der Kamp, Garth; Schmidt, Randy

    2017-07-01

    Changes of total moisture mass above an aquifer such as snow accumulation, soil moisture, and storage at the water table, represent changes of mechanical load acting on the aquifer. The resulting moisture-loading effects occur in all observation well records for confined aquifers. Deep observation wells therefore act as large-scale geological weighing lysimeters, referred to as "geolysimeters". Barometric pressure effects on groundwater levels are a similar response to surface loading and are familiar to every hydrogeologist dealing with the "barometric efficiency" of observation wells. Moisture-loading effects are small and generally not recognized because they are obscured by hydraulic head fluctuations due to other causes, primarily barometric pressure changes. For semiconfined aquifers, long-term moisture-loading effects may be dissipated and obscured by transient flow through overlying aquitards. Removal of barometric and earth tide effects from observation well records allows identification of moisture loading and comparison with hydrological observations, and also comparison with the results of numerical models that can account for transient groundwater flow.

  4. Flood water storage as a resource for agriculture and groundwater recharge: the empting of artificial leaking ponds

    Science.gov (United States)

    D'Oria, M.; Tanda, M.; Zanini, A.

    2008-12-01

    The large industrialization, intensive agriculture and the increasing population is giving rise to a lack of water resources. There is the need of capturing runoff for storing the water and using it during dry periods, but people now opposes to the realization of new dams. In Italy Public Authorities are showing a great interest in using ponds or small lakes located in the fluvial surroundings for storing water. The reservoirs can be filled up during flood events and can become, maintaining the water for a certain period, a resource for agriculture and a source of artificial recharge of groundwater. The hydraulic risks in the management of such small structures and the economic budget are lower than those involved in traditional reservoirs. In this work we propose a set of relationships with the aim of describing the interactions between the pond lakes and the beneath groundwater. This methodology allows to estimate the emptying time of the lake and its relative flow rate in a very fast way. It requires only a few parameters: the geometry of the problem, the initial lake and groundwater level and the hydraulic parameters of the aquifer and of the bottom of the lake. The solution of the problem was split in two cases: groundwater level always below the lakebed and groundwater level interacting with the lake level. It is possible to identify the two cases comparing the maximum flow rate drained from the aquifer (QS) to the one provided by the lake (QL). If QS is greater than QL the groundwater level maintains below the lakebed and vice versa. The two cases are well represented by simple relationships developed by the authors. These relationships were obtained using the results provided by a numerical model developed using MODFLOW 2000 with the LAKE3 package. Considering the first case, the relationship between the lake, groundwater level, the time and the leakance is represented by a straight line in a semi-logarithmic plane. In the case of the lake interconnected

  5. Exploring parameter effects on the economic outcomes of groundwater-based developments in remote, low-resource settings

    Science.gov (United States)

    Abramson, Adam; Adar, Eilon; Lazarovitch, Naftali

    2014-06-01

    Groundwater is often the most or only feasible safe drinking water source in remote, low-resource areas, yet the economics of its development have not been systematically outlined. We applied AWARE (Assessing Water Alternatives in Remote Economies), a recently developed Decision Support System, to investigate the costs and benefits of groundwater access and abstraction for non-networked, rural supplies. Synthetic profiles of community water services (n = 17,962), defined across 13 parameters' values and ranges relevant to remote areas, were applied to the decision framework, and the parameter effects on economic outcomes were investigated. Regressions and analysis of output distributions indicate that the most important factors determining the cost of water improvements include the technological approach, the water service target, hydrological parameters, and population density. New source construction is less cost-effective than the use or improvement of existing wells, but necessary for expanding access to isolated households. We also explored three financing approaches - willingness-to-pay, -borrow, and -work - and found that they significantly impact the prospects of achieving demand-driven cost recovery. The net benefit under willingness to work, in which water infrastructure is coupled to community irrigation and cash payments replaced by labor commitments, is impacted most strongly by groundwater yield and managerial factors. These findings suggest that the cost-benefit dynamics of groundwater-based water supply improvements vary considerably by many parameters, and that the relative strengths of different development strategies may be leveraged for achieving optimal outcomes.

  6. An Aquifer Storage and Recovery system with reclaimed wastewater to preserve native groundwater resources in El Paso, Texas.

    Science.gov (United States)

    Sheng, Zhuping

    2005-06-01

    The traditional concept of Aquifer Storage and Recovery (ASR) has been emphasized and extensively applied for water resources conservation in arid and semi-arid regions using groundwater systems as introduced in Pyne's book titled Groundwater Recharge and Wells. This paper extends the ASR concept to an integrated level in which either treated or untreated surface water or reclaimed wastewater is stored in a suitable aquifer through a system of spreading basins, infiltration galleries and recharge wells; and part or all of the stored water is recovered through production wells, dual function recharge wells, or by streams receiving increased discharge from the surrounding recharged aquifer as needed. In this paper, the author uses the El Paso Water Utilities (EPWU) ASR system for injection of reclaimed wastewater into the Hueco Bolson aquifer as an example to address challenges and resolutions faced during the design and operation of an ASR system under a new ASR system definition. This new ASR system concept consists of four subsystems: source water, storage space-aquifer, recharge facilities and recovery facilities. Even though facing challenges, this system has successfully recharged approximately 74.7 million cubic meters (19.7 billion gallons) of reclaimed wastewater into the Hueco Bolson aquifer through 10 recharge wells in the last 18 years. This ASR system has served dual purposes: reuse of reclaimed wastewater to preserve native groundwater, and restoration of groundwater by artificial recharge of reclaimed wastewater into the Hueco Bolson aquifer.

  7. Decision support model for assessing aquifer pollution hazard and prioritizing groundwater resources management in the wet Pampa plain, Argentina.

    Science.gov (United States)

    Lima, M Lourdes; Romanelli, Asunción; Massone, Héctor E

    2013-06-01

    This paper gives an account of the implementation of a decision support system for assessing aquifer pollution hazard and prioritizing subwatersheds for groundwater resources management in the southeastern Pampa plain of Argentina. The use of this system is demonstrated with an example from Dulce Stream Basin (1,000 km(2) encompassing 27 subwatersheds), which has high level of agricultural activities and extensive available data regarding aquifer geology. In the logic model, aquifer pollution hazard is assessed as a function of two primary topics: groundwater and soil conditions. This logic model shows the state of each evaluated landscape with respect to aquifer pollution hazard based mainly on the parameters of the DRASTIC and GOD models. The decision model allows prioritizing subwatersheds for groundwater resources management according to three main criteria including farming activities, agrochemical application, and irrigation use. Stakeholder participation, through interviews, in combination with expert judgment was used to select and weight each criterion. The resulting subwatershed priority map, by combining the logic and decision models, allowed identifying five subwatersheds in the upper and middle basin as the main aquifer protection areas. The results reasonably fit the natural conditions of the basin, identifying those subwatersheds with shallow water depth, loam-loam silt texture soil media and pasture land cover in the middle basin, and others with intensive agricultural activity, coinciding with the natural recharge area to the aquifer system. Major difficulties and some recommendations of applying this methodology in real-world situations are discussed.

  8. Groundwater resources of the aquifers of the northern Central African Republic (Ouham Province). First hydrogeological investigations in a changing environment.

    Science.gov (United States)

    Djebebe-Ndjiguim, Chantal; Foto, Eric; Backo, Salé; Nguerekossi, Bruno; Zoudamba, Narcisse; Basse-Keke, Eric; Allahdin, Oscar; Huneau, Frédéric; Garel, Emilie; Celle-Jeanton, Hélène; Mabingui, Joseph

    2017-04-01

    Groundwater is a key factor in the socio-economic development of African societies. This is particularly true for the Lake Chad Basin countries for which groundwater is the main water resource for both drinking water supply for population and agriculture, whether small or large scale. The Central African Republic (CAR) occupies a strategic place in the Lake Chad Basin since most waters feeding the different tributaries of the Chari River, which is the main water source of the Lake Chad, are originating from its territory. Indeed, the Northern CAR and particularly the Ouham Province, at the head of the whole Chad endoreic watershed, benefits from favourable rainfall conditions. Unfortunately, very little hydrological and hydrogeological information is available for this area which has never been investigated in terms of geochemical and isotope characterisation. The only available spares technical and scientific investigations over the area are dating from the 1960's. Unfortunately the Lake Chad basin has undergone strong climatological evolutions since the 1970's and hydrological information needs to be updated. The objectives of this study are to characterise groundwater from the Ouham Province in order to better appreciate the hydrogeological processes taking place in the recharge area of the Southern Lake Chad Basin. Isotope hydrology combined with geochemistry of groundwater has now proven being the best approach in under-documented territories to have a first diagnostic on the dynamics and quality of available resources. In this purpose combined hydrogeochemical and isotopic investigations (18O, 2H and 3H of the water molecule) have been launched to constrain groundwater origin, recharge processes, quality, residence time and anthropogenic fingerprint on aquifers. After two sampling campaigns it was possible to draw a general pattern of the hydrogeological and hydrochemical conditions in the region. The Ouham province is mostly composed of Precambrian

  9. Rural and agricultural value of groundwater as an economic resource in the Limpopo region

    CSIR Research Space (South Africa)

    Mahumani, BK

    2009-03-01

    Full Text Available of effective groundwater pricing policy for better groundwater demand management in both domestic and agricultural use. Such policies could contribute to meeting the societal goals of economic efficiency and social equity. iv... ook die belangrikste bron van water, behalwe gedurende sekere tye wanneer besproeiingsdamme met vloedwater gevul word. Dan word grondwater om ekonomiese redes gedeeltelik met oppervlakwater vervang. In hierdie studie is die ekonomiese waarde...

  10. Optimizing water resources management in large river basins with integrated surface water-groundwater modeling: A surrogate-based approach

    Science.gov (United States)

    Wu, Bin; Zheng, Yi; Wu, Xin; Tian, Yong; Han, Feng; Liu, Jie; Zheng, Chunmiao

    2015-04-01

    Integrated surface water-groundwater modeling can provide a comprehensive and coherent understanding on basin-scale water cycle, but its high computational cost has impeded its application in real-world management. This study developed a new surrogate-based approach, SOIM (Surrogate-based Optimization for Integrated surface water-groundwater Modeling), to incorporate the integrated modeling into water management optimization. Its applicability and advantages were evaluated and validated through an optimization research on the conjunctive use of surface water (SW) and groundwater (GW) for irrigation in a semiarid region in northwest China. GSFLOW, an integrated SW-GW model developed by USGS, was employed. The study results show that, due to the strong and complicated SW-GW interactions, basin-scale water saving could be achieved by spatially optimizing the ratios of groundwater use in different irrigation districts. The water-saving potential essentially stems from the reduction of nonbeneficial evapotranspiration from the aqueduct system and shallow groundwater, and its magnitude largely depends on both water management schemes and hydrological conditions. Important implications for water resources management in general include: first, environmental flow regulation needs to take into account interannual variation of hydrological conditions, as well as spatial complexity of SW-GW interactions; and second, to resolve water use conflicts between upper stream and lower stream, a system approach is highly desired to reflect ecological, economic, and social concerns in water management decisions. Overall, this study highlights that surrogate-based approaches like SOIM represent a promising solution to filling the gap between complex environmental modeling and real-world management decision-making.

  11. Large-Scale Water Resources Management within the Framework of GLOWA-Danube - Part A: The Groundwater Model

    Science.gov (United States)

    Barthel, R.; Rojanschi, V.; Wolf, J.; Braun, J.

    2003-04-01

    the catchment developed by the research group uses a finite difference approach (MODFLOW). A transport model (nitrogen) will be added in a second stage (MT3D). A three-dimensional conceptual hydrogeological model consisting of four layers was developed. Only aquifers with basin-wide occurrence are considered. Aquifers on the local scale cannot be included in the model due to insufficient data availability, the model grid resolution (1km2) used and various limitations arising from the MODFLOW-approach. The cell size of 1 km is compulsory for all models in DANUBIA in order to facilitate 1:1 parameter exchange. The concept of DANUBIA is based on the parallel execution of strictly independent disciplinary models. At each time step, the required parameters are exchanged. On the "physical side" the groundwater model has interfaces to a soil water and a surface water model which provide important parameters that are used as model boundary conditions. The soil water model calculates the groundwater recharge as the infiltration through a layered soil zone. The surface water model calculates the heads in the rivers, which are used to determine flow from the aquifers to the rivers and vice versa. The main aim of the groundwater model is to assess and forecast quantity and quality of the groundwater resources together with the other physically based models under conditions of global change. On the "socio-economic side", the groundwater model exchanges data with the so-called "Actors" component, a group of models concerned with the human impact on the water cycle. The amount of groundwater extraction for drinking water purposes is a boundary condition of the groundwater model calculated by the Actors models. The feedback between demand and supply invokes the need for complex optimization algorithms.

  12. Simulation of groundwater flow and analysis of the effects of water-management options in the North Platte Natural Resources District, Nebraska

    Science.gov (United States)

    Peterson, Steven M.; Flynn, Amanda T.; Vrabel, Joseph; Ryter, Derek W.

    2015-08-12

    The North Platte Natural Resources District (NPNRD) has been actively collecting data and studying groundwater resources because of concerns about the future availability of the highly inter-connected surface-water and groundwater resources. This report, prepared by the U.S. Geological Survey in cooperation with the North Platte Natural Resources District, describes a groundwater-flow model of the North Platte River valley from Bridgeport, Nebraska, extending west to 6 miles into Wyoming. The model was built to improve the understanding of the interaction of surface-water and groundwater resources, and as an optimization tool, the model is able to analyze the effects of water-management options on the simulated stream base flow of the North Platte River. The groundwater system and related sources and sinks of water were simulated using a newton formulation of the U.S. Geological Survey modular three-dimensional groundwater model, referred to as MODFLOW–NWT, which provided an improved ability to solve nonlinear unconfined aquifer simulations with wetting and drying of cells. Using previously published aquifer-base-altitude contours in conjunction with newer test-hole and geophysical data, a new base-of-aquifer altitude map was generated because of the strong effect of the aquifer-base topography on groundwater-flow direction and magnitude. The largest inflow to groundwater is recharge originating from water leaking from canals, which is much larger than recharge originating from infiltration of precipitation. The largest component of groundwater discharge from the study area is to the North Platte River and its tributaries, with smaller amounts of discharge to evapotranspiration and groundwater withdrawals for irrigation. Recharge from infiltration of precipitation was estimated with a daily soil-water-balance model. Annual recharge from canal seepage was estimated using available records from the Bureau of Reclamation and then modified with canal

  13. Rapid groundwater-related land subsidence in Yemen observed by multi-temporal InSAR

    KAUST Repository

    Abdullin, Ayrat

    2015-04-01

    Several basins in Yemen are suffering from a rapid drawdown of groundwater, which is the most important water source for agricultural irrigation, industry and domestic use. However, detailed geodetic measurements in the region have been lacking and the extent and magnitude of groundwater-related land subsidence has been poorly known. We used 13 ascending ALOS and 15 descending Envisat images to study land subsidence of several basins in Yemen, with a special focus on the Sana\\'a and Mabar basins. From multitemporal synthetic aperture radar interferometric analysis (persistent scatterers (PS) and small baseline subsets (SBAS)) we examined the spatio-temporal behavior of the subsidence induced by depletion of groundwater aquifer systems from November 2003 to February 2011. In the interferometric data processing, we carefully chose interferogram pairs to minimize spatial and temporal decorrelation, because of high subsidence rates and the type of land cover. Our results show that the spatial pattern of subsidence remained quite stable during the observation period in both the Sana\\'a and Mabar basins. In the Sana\\'a basin, the maximum subsidence rate exceeded 14 cm/year in the radar line-of-sight (LOS) direction between 2003 and 2008 in an agricultural area just north of Sana\\'a city, where water wells have been drying up according to the well data. The subsidence rate was lower in the urban areas, or approximately 1 cm/year, exhibiting annual variations. The main subsidence was found in the center and southern parts of the city, while deformation in the northern part is less obvious. For the Mabar basin, the subsidence rate exceeded 30 cm/year in the agricultural area north of the town of Mabar during 2007 - 2011. The southern part of the Mabar basin also experienced high subsidence rates, although somewhat lower than to the north. Excessive water pumping is the main cause of the ground subsidence and it has already led to extensive ground fracturing at the edge

  14. Research Project on CO2 Geological Storage and Groundwater Resources: Water Quality Effects Caused by CO2 Intrusion into Shallow Groundwater

    Energy Technology Data Exchange (ETDEWEB)

    Birkholzer, Jens; Apps, John; Zheng, Liange; Zhang, Yingqi; Xu, Tianfu; Tsang, Chin-Fu

    2008-10-01

    One promising approach to reduce greenhouse gas emissions is injecting CO{sub 2} into suitable geologic formations, typically depleted oil/gas reservoirs or saline formations at depth larger than 800 m. Proper site selection and management of CO{sub 2} storage projects will ensure that the risks to human health and the environment are low. However, a risk remains that CO{sub 2} could migrate from a deep storage formation, e.g. via local high-permeability pathways such as permeable faults or degraded wells, and arrive in shallow groundwater resources. The ingress of CO{sub 2} is by itself not typically a concern to the water quality of an underground source of drinking water (USDW), but it will change the geochemical conditions in the aquifer and will cause secondary effects mainly induced by changes in pH, in particular the mobilization of hazardous inorganic constituents present in the aquifer minerals. Identification and assessment of these potential effects is necessary to analyze risks associated with geologic sequestration of CO{sub 2}. This report describes a systematic evaluation of the possible water quality changes in response to CO{sub 2} intrusion into aquifers currently used as sources of potable water in the United States. Our goal was to develop a general understanding of the potential vulnerability of United States potable groundwater resources in the event of CO{sub 2} leakage. This goal was achieved in two main tasks, the first to develop a comprehensive geochemical model representing typical conditions in many freshwater aquifers (Section 3), the second to conduct a systematic reactive-transport modeling study to quantify the effect of CO{sub 2} intrusion into shallow aquifers (Section 4). Via reactive-transport modeling, the amount of hazardous constituents potentially mobilized by the ingress of CO{sub 2} was determined, the fate and migration of these constituents in the groundwater was predicted, and the likelihood that drinking water

  15. Resources

    Science.gov (United States)

    ... resources Alzheimer's - resources Anorexia nervosa - resources Arthritis - resources Asthma and allergy - resources Autism - resources Blindness - resources BPH - resources Breastfeeding - resources Bulimia - resources Burns - resources Cancer - resources Cerebral ...

  16. THE GROUNDWATER RESOURCES AND ITS SUSTAINABLE DEVELOPMENT IN THE SOUTH EDGE OF TARIM BASIN

    Institute of Scientific and Technical Information of China (English)

    2001-01-01

    There is a potential to certain extend for groundwater development in the piedmont plain in south edge of Tarim Basin. If the surface water use keeps the scale as present, the maximum safe yield of groundwater is about 2. 05 × 109m3/a that is 55.8% of the recharge. Thus the evapotranspiration discharge will reduce 60. 4%, while spring water reducing 35.6%. If the surface water use rate is up to 80% and coefficient of canal water use increase to 0. 55 in the future, the maximum safe yield of groundwater will reduce to 1.85 × 109m3/a with the recharge reducing to 3.1 × 109m3. However, the sustainable groundwater development is depended on the protection of the quality aspect linked with the quantity aspect. In particular, protection of the glacier and water conservation forestry in the Kunlun Mountains and coordinating development of surface water and groundwater should be taken seriously. Besides, the legislation, administrative management and the technology construction, and ability construction are also critical important and necessary.

  17. Dynamic Attribution of Global Water Demand to Surface Water and Groundwater Resources: Effects of Abstractions and Return Flows on River Discharge

    Science.gov (United States)

    de Graaf, Inge; van Beek, Rens; Wada, Yoshi; Bierkens, Marc

    2013-04-01

    As human water demand is increasing worldwide, groundwater is abstracted at rates that exceed groundwater recharge in many areas, resulting in depletion of existing groundwater stocks. Most studies, that focus on human water consumption and water stress indicate a gap between water demand and availability. However, between studies very different assumptions are made on how water abstraction is divided between surface water, groundwater, and other resources. Moreover, simplified assumptions are used of the interactions between groundwater and surface water. Here, we simulate at the global scale, the dynamic attribution of total water demand to surface water and groundwater resources, based on actual water availability and accounting for return flows and surface water- groundwater interactions. The global hydrological model PCR-GLOBWB is used to simulate water storages, abstractions, and return flows for the model period 1960-2010, with a daily time step at 0.5° x 0.5° spatial resolution. Total water demand is defined as requirements for irrigation, industry, and domestic use. Water abstractions are variably taken from surface water and groundwater resources depending on availability of both resources. Return flows of non-consumed abstracted water contribute to a single source; those of irrigation recharging groundwater, those of industry and domestic use discharging to surface waters. Groundwater abstractions are taken from renewable groundwater, or when exceeding recharge from an alternative unlimited resource. This resource consists of non-renewable groundwater, or non-local water, the former being an estimate of groundwater depletion. Results show that worldwide the effect of water abstractions is evident, especially on the magnitude and frequency of low flows when the contribution of groundwater through baseflow is substantial. River regimes are minimally affected by abstractions in industrial regions because of the high return flows. In irrigated regions the

  18. A Conflict-Resolution Model for the Conjunctive Use of Surface and Groundwater Resources that Considers Water-Quality Issues: A Case Study

    Science.gov (United States)

    Bazargan-Lari, Mohammad Reza; Kerachian, Reza; Mansoori, Abbas

    2009-03-01

    The conjunctive use of surface and groundwater resources is one alternative for optimal use of available water resources in arid and semiarid regions. The optimization models proposed for conjunctive water allocation are often complicated, nonlinear, and computationally intensive, especially when different stakeholders are involved that have conflicting interests. In this article, a new conflict-resolution methodology developed for the conjunctive use of surface and groundwater resources using Nondominated Sorting Genetic Algorithm II (NSGA-II) and Young Conflict-Resolution Theory (YCRT) is presented. The proposed model is applied to the Tehran aquifer in the Tehran metropolitan area of Iran. Stakeholders in the study area have conflicting interests related to water supply with acceptable quality, pumping costs, groundwater quality, and groundwater table fluctuations. In the proposed methodology, MODFLOW and MT3D groundwater quantity and quality simulation models are linked with the NSGA-II optimization model to develop Pareto fronts among the objectives. The best solutions on the Pareto fronts are then selected using YCRT. The results of the proposed model show the significance of applying an integrated conflict-resolution approach to conjunctive use of surface and groundwater resources in the study area.

  19. Geoelectrical parameter-based multivariate regression borehole yield model for predicting aquifer yield in managing groundwater resource sustainability

    Directory of Open Access Journals (Sweden)

    Kehinde Anthony Mogaji

    2016-07-01

    Full Text Available This study developed a GIS-based multivariate regression (MVR yield rate prediction model of groundwater resource sustainability in the hard-rock geology terrain of southwestern Nigeria. This model can economically manage the aquifer yield rate potential predictions that are often overlooked in groundwater resources development. The proposed model relates the borehole yield rate inventory of the area to geoelectrically derived parameters. Three sets of borehole yield rate conditioning geoelectrically derived parameters—aquifer unit resistivity (ρ, aquifer unit thickness (D and coefficient of anisotropy (λ—were determined from the acquired and interpreted geophysical data. The extracted borehole yield rate values and the geoelectrically derived parameter values were regressed to develop the MVR relationship model by applying linear regression and GIS techniques. The sensitivity analysis results of the MVR model evaluated at P ⩽ 0.05 for the predictors ρ, D and λ provided values of 2.68 × 10−05, 2 × 10−02 and 2.09 × 10−06, respectively. The accuracy and predictive power tests conducted on the MVR model using the Theil inequality coefficient measurement approach, coupled with the sensitivity analysis results, confirmed the model yield rate estimation and prediction capability. The MVR borehole yield prediction model estimates were processed in a GIS environment to model an aquifer yield potential prediction map of the area. The information on the prediction map can serve as a scientific basis for predicting aquifer yield potential rates relevant in groundwater resources sustainability management. The developed MVR borehole yield rate prediction mode provides a good alternative to other methods used for this purpose.

  20. Considering groundwater use to improve the assessment of groundwater pumping for irrigation in North Africa

    Science.gov (United States)

    Massuel, Sylvain; Amichi, Farida; Ameur, Fatah; Calvez, Roger; Jenhaoui, Zakia; Bouarfa, Sami; Kuper, Marcel; Habaieb, Hamadi; Hartani, Tarik; Hammani, Ali

    2017-04-01

    Groundwater resources in semi-arid areas and especially in the Mediterranean face a growing demand for irrigated agriculture and, to a lesser extent, for domestic uses. Consequently, groundwater reserves are affected and water-table drops are widely observed. This leads to strong constraints on groundwater access for farmers, while managers worry about the future evolution of the water resources. A common problem for building proper groundwater management plans is the difficulty in assessing individual groundwater withdrawals at regional scale. Predicting future trends of these groundwater withdrawals is even more challenging. The basic question is how to assess the water budget variables and their evolution when they are deeply linked to human activities, themselves driven by countless factors (access to natural resources, public policies, market, etc.). This study provides some possible answers by focusing on the assessment of groundwater withdrawals for irrigated agriculture at three sites in North Africa (Morocco, Tunisia and Algeria). Efforts were made to understand the different features that influence irrigation practices, and an adaptive user-oriented methodology was used to monitor groundwater withdrawals. For each site, different key factors affecting the regional groundwater abstraction and its past evolution were identified by involving farmers' knowledge. Factors such as farmer access to land and groundwater or development of public infrastructures (electrical distribution network) are crucial to decode the results of well inventories and assess the regional groundwater abstraction and its future trend. This leads one to look with caution at the number of wells cited in the literature, which could be oversimplified.

  1. Considering groundwater use to improve the assessment of groundwater pumping for irrigation in North Africa

    Science.gov (United States)

    Massuel, Sylvain; Amichi, Farida; Ameur, Fatah; Calvez, Roger; Jenhaoui, Zakia; Bouarfa, Sami; Kuper, Marcel; Habaieb, Hamadi; Hartani, Tarik; Hammani, Ali

    2017-09-01

    Groundwater resources in semi-arid areas and especially in the Mediterranean face a growing demand for irrigated agriculture and, to a lesser extent, for domestic uses. Consequently, groundwater reserves are affected and water-table drops are widely observed. This leads to strong constraints on groundwater access for farmers, while managers worry about the future evolution of the water resources. A common problem for building proper groundwater management plans is the difficulty in assessing individual groundwater withdrawals at regional scale. Predicting future trends of these groundwater withdrawals is even more challenging. The basic question is how to assess the water budget variables and their evolution when they are deeply linked to human activities, themselves driven by countless factors (access to natural resources, public policies, market, etc.). This study provides some possible answers by focusing on the assessment of groundwater withdrawals for irrigated agriculture at three sites in North Africa (Morocco, Tunisia and Algeria). Efforts were made to understand the different features that influence irrigation practices, and an adaptive user-oriented methodology was used to monitor groundwater withdrawals. For each site, different key factors affecting the regional groundwater abstraction and its past evolution were identified by involving farmers' knowledge. Factors such as farmer access to land and groundwater or development of public infrastructures (electrical distribution network) are crucial to decode the results of well inventories and assess the regional groundwater abstraction and its future trend. This leads one to look with caution at the number of wells cited in the literature, which could be oversimplified.

  2. Hydrogeological and geophysical study for deeper groundwater resource in quartzitic hard rock ridge region from 2D resistivity data

    Indian Academy of Sciences (India)

    Dewashish Kumar; V Ananda Rao; V S Sarma

    2014-04-01

    Electrical resistivity method is a versatile and economical technique for groundwater prospecting in different geological settings due to wide spectrum of resistivity compared to other geophysical parameters. Exploration and exploitation of groundwater, a vital and precious resource, is a challenging task in hard rock, which exhibits inherent heterogeneity. In the present study, two-dimensional Electrical Resistivity Tomography (2D-ERT) technique using two different arrays, viz., pole–dipole and pole–pole, were deployed to look into high signal strength data in a tectonically disturbed hard rock ridge region for groundwater. Four selected sites were investigated. 2D subsurface resistivity tomography data were collected using Syscal Pro Switch-10 channel system and covered a 2 km long profile in a tough terrain. The hydrogeological interpretation based on resistivity models reveal the water horizons trap within the clayey sand and weathered/fractured quartzite formations. Aquifer resistivity lies between ∼3–35 and 100–200 m. The results of the resistivity models decipher potential aquifer lying between 40 and 88 m depth, nevertheless, it corroborates with the static water level measurements in the area of study. The advantage of using pole–pole in conjunction with the pole–dipole array is well appreciated and proved worth which gives clear insight of the aquifer extent, variability and their dimension from shallow to deeper strata from the hydrogeological perspective in the present geological context.

  3. Integrated socio-hydrogeological approach to tackle nitrate contamination in groundwater resources. The case of Grombalia Basin (Tunisia).

    Science.gov (United States)

    Re, V; Sacchi, E; Kammoun, S; Tringali, C; Trabelsi, R; Zouari, K; Daniele, S

    2017-09-01

    Nitrate contamination still remains one of the main groundwater quality issues in several aquifers worldwide, despite the perduring efforts of the international scientific community to effectively tackle this problem. The classical hydrogeological and isotopic investigations are obviously of paramount importance for the characterization of contaminant sources, but are clearly not sufficient for the correct and long-term protection of groundwater resources. This paper aims at demonstrating the effectiveness of the socio-hydrogeological approach as the best tool to tackle groundwater quality issues, while contributing bridging the gap between science and society. An integrated survey, including land use, hydrochemical (physicochemical parameters and major ions) and isotopic (δ(15)NNO3 and δ(18)ONO3) analyses, coupled to capacity building and participatory activities was carried out to correctly attribute the nitrate origin in groundwater from the Grombalia Basin (North Tunisia), a region where only synthetic fertilizers have been generally identified as the main source of such pollution. Results demonstrates that the basin is characterized by high nitrate concentrations, often exceeding the statutory limits for drinking water, in both the shallow and deep aquifers, whereas sources are associated to both agricultural and urban activities. The public participation of local actors proved to be a fundamental element for the development of the hydrogeological investigation, as it permitted to obtain relevant information to support data interpretation, and eventually guaranteed the correct assessment of contaminant sources in the studied area. In addition, such activity, if adequately transferred to regulators, will ensure the effective adoption of management practices based on the research outcomes and tailored on the real needs of the local population, proving the added value to include it in any integrated investigation. Copyright © 2017 Elsevier B.V. All rights

  4. Assessment of Groundwater Resources in the Context of Climate Change and Population Growth: Case of the Klela Basin in Southern Mali

    Directory of Open Access Journals (Sweden)

    Adama Toure

    2017-07-01

    Full Text Available Groundwater in the Klela basin in Mali, a subbasin of the Bani basin (one of the main tributaries of the Niger River, is required for domestic use, irrigation and livestock. Furthermore, water supply of the city of Sikasso directly depends on the groundwater resources, which are under pressure caused by increased water demand as well as climate variability and climate change. As a consequence, freshwater availability is being threatened which can have a direct negative impact on irrigation agriculture. The aim of this study was to evaluate future behavior of groundwater resources in the context of climate change and population growth using socio-economic and population growth scenarios for water demand and the Representative Concentration Pathways scenarios (RCP4.5 and RCP8.5 data for calculating groundwater recharge using the Thornthwaite model. The WEAP (Water Evaluation and Planning system model was applied to balance water availability and demand and to compute changes in groundwater storage up to 2050. The overall results show that groundwater recharge as well as storage is decreasing over time, especially in the 2030s which can lead to severe agricultural droughts in this period. Recharge declined by approximatively 49% and stored groundwater by 24% over the study period.

  5. Groundwater Recharge Estimation And Water Resources Assessment In A Tropical Crystalline Basement Aquifer

    NARCIS (Netherlands)

    Nyagwambo, N.L.

    2006-01-01

    While most groundwater recharge estimation methods give reasonable long-term annual average estimates very few if any methods offer guidance on monthly recharge. In crystalline basement aquifers (CBAs) the problem is compounded by the high seasonal, intra-annual and inter-annual variability. The chl

  6. Participatory rural appraisal to assess groundwater resources in Al-Mujaylis, Tihama Coastal Plain, Yemen

    NARCIS (Netherlands)

    Al-Qubatee, W.S.M.; Ritzema, H.P.; Al-Weshall, Adel; Steenbergen, van F.; Hellegers, P.J.G.J.

    2017-01-01

    A participatory rural appraisal (PRA) conducted in the Al-Mujaylis area, Tihama Coastal Plain, Yemen provided a contribution, as a bottom-up approach, to the assessment of the needs of communities and their views on how to avoid groundwater degradation. It was found that PRA tools could be applied

  7. Interannual to multidecadal climate forcings on groundwater resources of the U.S. West Coast

    Science.gov (United States)

    Velasco, Elzie M; Gurdak, Jason J.; Dickinson, Jesse; Ferre, T.P.A; Corona, Claudia

    2016-01-01

    Study regionThe U.S. West Coast, including the Pacific Northwest and California Coastal Basins aquifer systems.Study focusGroundwater response to interannual to multidecadal climate variability has important implications for security within the water–energy–food nexus. Here we use Singular Spectrum Analysis to quantify the teleconnections between AMO, PDO, ENSO, and PNA and precipitation and groundwater level fluctuations. The computer program DAMP was used to provide insight on the influence of soil texture, depth to water, and mean and period of a surface infiltration flux on the damping of climate signals in the vadose zone.New hydrological insights for the regionWe find that PDO, ENSO, and PNA have significant influence on precipitation and groundwater fluctuations across a north-south gradient of the West Coast, but the lower frequency climate modes (PDO) have a greater influence on hydrologic patterns than higher frequency climate modes (ENSO and PNA). Low frequency signals tend to be preserved better in groundwater fluctuations than high frequency signals, which is a function of the degree of damping of surface variable fluxes related to soil texture, depth to water, mean and period of the infiltration flux. The teleconnection patterns that exist in surface hydrologic processes are not necessarily the same as those preserved in subsurface processes, which are affected by damping of some climate variability signals within infiltrating water.

  8. Hydrogeochemical features of groundwater resources in Tabriz plain, northwest of Iran

    Science.gov (United States)

    Barzegar, Rahim; Asghari Moghaddam, Asghar; Tziritis, Evangelos

    2017-03-01

    The present study seeks to evaluate the hydrogeochemistry of Tabriz plain in NW Iran, through major ion chemistry and their spatial variations. In order to accomplish these, groundwater sampling from 30 shallow and deep wells in the plain were carried out in July 2012. The water samples were analyzed for various physicochemical parameters such as pH, EC, Na+, Ca2+, K+, Mg2+, Cl-, CO3 2-, HCO3 -, SO4 2- and NO3 -. Chadha's diagram demonstrates that most of the groundwaters belonged to the Na-Cl and mixed Ca-Mg-Cl hydrochemical facies. The concentrations of some major ions in groundwater are above the permissible limit for drinking and domestic purposes except for a few locations. The results of saturation index computation show that dissolution of gypsum, anhydrite, halite and silicate minerals occurs frequently across the study area, whereas the groundwater is supersaturated with regard to calcite and dolomite. Cross-plots show that weathering and dissolution of different rocks and minerals, ion exchange, reverse ion exchange and anthropogenic activities, especially agricultural activities, are effective in hydrogeochemistry of the study area.

  9. Groundwater recharge estimation and water resources assessment in a tropical crystalline basement aquifer

    NARCIS (Netherlands)

    Nyagwambo, N.L.

    2006-01-01

    Groundwater recharge estimation in crystalline basement aquifers in semi-arid tropical areas is best estimated at monthly time scales as this best captures the dynamics of recharge processes in these areas. Whilst it is standard practice to use at least two methods to estimate the recharge it may be

  10. Groundwater recharge estimation and water resources assessment in a tropical crystalline basement aquifer

    NARCIS (Netherlands)

    Nyagwambo, N.L.

    2006-01-01

    Groundwater recharge estimation in crystalline basement aquifers in semi-arid tropical areas is best estimated at monthly time scales as this best captures the dynamics of recharge processes in these areas. Whilst it is standard practice to use at least two methods to estimate the recharge it may be

  11. Numerical Simulation of Groundwater Flow, Resource Optimization, and Potential Effects of Prolonged Drought for the Citizen Potawatomi Nation Tribal Jurisdictional Area, Central Oklahoma

    Science.gov (United States)

    Ryter, Derek W.; Kunkel, Christopher D.; Peterson, Steven M.; Traylor, Jonathan P.

    2015-08-13

    A hydrogeological study including two numerical groundwater-flow models was completed for the Citizen Potawatomi Nation Tribal Jurisdictional Area of central Oklahoma. One numerical groundwater-flow model, the Citizen Potawatomi Nation model, encompassed the jurisdictional area and was based on the results of a regional-scale hydrogeological study and numerical groundwater flow model of the Central Oklahoma aquifer, which had a geographic extent that included the Citizen Potawatomi Nation Tribal Jurisdictional Area. The Citizen Potawatomi Nation numerical groundwater-flow model included alluvial aquifers not in the original model and improved calibration using automated parameter-estimation techniques. The Citizen Potawatomi Nation numerical groundwater-flow model was used to analyze the groundwater-flow system and the effects of drought on the volume of groundwater in storage and streamflow in the North Canadian River. A more detailed, local-scale inset model was constructed from the Citizen Potawatomi Nation model to estimate available groundwater resources for two Citizen Potawatomi Nation economic development zones near the North Canadian River, the geothermal supply area and the Iron Horse Industrial Park.

  12. Addressing structural and observational uncertainty in resource management.

    Science.gov (United States)

    Fackler, Paul; Pacifici, Krishna

    2014-01-15

    Most natural resource management and conservation problems are plagued with high levels of uncertainties, which make good decision making difficult. Although some kinds of uncertainties are easily incorporated into decision making, two types of uncertainty present more formidable difficulties. The first, structural uncertainty, represents our imperfect knowledge about how a managed system behaves. The second, observational uncertainty, arises because the state of the system must be inferred from imperfect monitoring systems. The former type of uncertainty has been addressed in ecology using Adaptive Management (AM) and the latter using the Partially Observable Markov Decision Processes (POMDP) framework. Here we present a unifying framework that extends standard POMDPs and encompasses both standard POMDPs and AM. The approach allows any system variable to be observed or not observed and uses any relevant observed variable to update beliefs about unknown variables and parameters. This extends standard AM, which only uses realizations of the state variable to update beliefs and extends standard POMDP by allowing more general stochastic dependence among the observable variables and the state variables. This framework enables both structural and observational uncertainty to be simultaneously modeled. We illustrate the features of the extended POMDP framework with an example.

  13. Investigating the salinization and freshening processes of coastal groundwater resources in Urmia aquifer, NW Iran.

    Science.gov (United States)

    Amiri, Vahab; Nakhaei, Mohammad; Lak, Razyeh; Kholghi, Majid

    2016-04-01

    This paper presents the results of an assessment about interaction between Urmia Lake (UL) and coastal groundwater in the Urmia aquifer (UA). This aquifer is the most significant contributor to the freshwater supply of the coastal areas. The use of hydrochemical facies can be very useful to identify the saltwater encroachment or freshening phases in the coastal aquifers. In this study, the analysis of salinization/freshening processes was carried out through the saturation index (SI), ionic deltas (Δ), binary diagrams, and hydrochemical facies evolution (HFE) diagram. Based on the Gibbs plot, the behavior of the major ions showed that the changes in the chemical composition of the groundwater are mainly controlled by the water-soil/rock interaction zone and few samples are relatively controlled by evaporation. A possible explanation for this phenomenon is that the deposited chloride and sulfate particles can form the minor salinity source in some coastal areas when washed down by precipitation. The SI calculations showed that all groundwater samples, collected in these periods, show negative saturation indices, which indicate undersaturation with respect to anhydrite, gypsum, and halite. In addition, except in a few cases, all other samples showed the undersaturation with respect to the carbonate minerals such as aragonite, calcite, and dolomite. Therefore, these minerals are susceptible to dissolution. In the dry season, the SI calculations showed more positive values with respect to dolomite, especially in the northern part of UA, which indicated a higher potential for precipitation and deposition of dolomite. The percentage of saltwater in the groundwater samples of Urmia plain was very low, ranging between 0.001 and 0.79 % in the wet season and 0.0004 and 0.81 % in the dry season. The results of HFE diagram, which was taken to find whether the aquifer was in the saltwater encroachment phase or in the freshening phase, indicated that except for a few wells

  14. Long term fluctuations of groundwater mine pollution in a sulfide mining district with dry Mediterranean climate: Implications for water resources management and remediation.

    Science.gov (United States)

    Caraballo, Manuel A; Macías, Francisco; Nieto, José Miguel; Ayora, Carlos

    2016-01-01

    Water resources management and restoration strategies, and subsequently ecological and human life quality, are highly influenced by the presence of short and long term cycles affecting the intensity of a targeted pollution. On this respect, a typical acid mine drainage (AMD) groundwater from a sulfide mining district with dry Mediterranean climate (Iberian Pyrite Belt, SW Spain) was studied to unravel the effect of long term weather changes in water flow rate and metal pollutants concentration. Three well differentiated polluting stages were observed and the specific geochemical, mineralogical and hydrological processes involved (pyrite and enclosing rocks dissolution, evaporitic salts precipitation-redisolution and pluviometric long term fluctuations) were discussed. Evidencing the importance of including longer background monitoring stage in AMD management and restoration strategies, the present study strongly advise a minimum 5-years period of AMD continuous monitoring previous to the design of any AMD remediation system in regions with dry Mediterranean climate. Copyright © 2015 Elsevier B.V. All rights reserved.

  15. Past, present and future formation of groundwater resources in northern part of Baltic Artesian Basin

    Science.gov (United States)

    Marandi, A.; Vallner, L.; Vaikmae, R.; Raidla, V.

    2012-04-01

    Cambrian-Vendian Aquifer System (CVAS) is the deepest confined aquifer system used for water consumption in northern part of Baltic Artesian Basin (BAB). A regional groundwater flow and transport model (Visual Modflow) was used to investigate the paleohydrogeological scientific and contemporary management problems of CVAS. The model covers the territory of Estonia and its close surrounding, all together 88,000 km2 and includes all main aquifers and aquitards from ground surface to as low as the impermeable part of the crystalline basement. Three-dimensional distribution of groundwater heads, flow directions, velocities, and rates as well as transport and budget characteristics were simulated by the model. Water composition was changed significantly during the last glaciations.Strongly depleted O and H stable isotope composition, absence of 3H and low radiocarbon concentration are the main indicators of glacial origin of groundwater in the Cambrian-Vendian aquifer in northern Estonia. The noble gas analyses allowed concluding, that palaeorecharge took place at temperatures around the freezing point. While in North Estonia, most of water was changed by glacial melt water, high salinity water is till preserved in Southern part of Estonia.First results of modeling suggest that during the intrusion period lasting 7.3-9.3 ka the front of glacial thaw water movement had southeast direction and reachedto 180-220 kmfrom CVAS outcrop in Baltic Sea. Confining layer of CVAS is cut through by deep buried valleys in several places in North Estonia making possible for modern precipitation to infiltrate into aquifer system in present day. In case of natural conditions, the water pressure of CVAS is few meters above sea level and most of valleys act as discharge areas for aquifers system. Two regional depression ones have formed in North Estonia as a result of groundwater use from CVAS. Water consumption changes the natural groundwater gradient, flow direction and thereforerecharge

  16. Water Quality Assessment of Groundwater Resources in Nagpur Region (India Based on WQI

    Directory of Open Access Journals (Sweden)

    P. N. Rajankar

    2009-01-01

    Full Text Available Water quality index (WQI has been calculated for different groundwater sources i.e. dug wells, bore wells and tube wells at Khaperkheda region, Maharashtra (India. Twenty two different sites were selected in post monsoon, winter and summer season. And water quality index was calculated using water quality index calculator given by National Sanitation Foundation (NSF information system. The calculated WQI showed fair water quality rating in post monsoon season which then changed to medium in summer and winter seasons for dug wells, but the bore wells and hand pumps showed medium water quality rating in all seasons where the quality was slightly differs in summer and winter season than post monsoon season, so the reasons to import water quality change and measures to be taken up in terms of groundwater quality management are required.

  17. Ground-water resources of the Bengasi area, Cyrenaica, United Kingdom of Libya

    Science.gov (United States)

    Doyel, William Watson; Maguire, Frank J.

    1964-01-01

    The Benpsi area of Libya, in the northwestern part of the Province of Cyrenaica (Wilayat Barqah), is semiarid, and available ground-water supplies in the area are relatively small. Potable ground water from known sources is reserved for the present and future needs of the city, and no surface-water supplies are available in the area. This investigation to evaluate known, as well as potential, water supplies in the area was undertaken as part of a larger program of ground-water investigations in Libya under the auspices of the U. S. Operations Mission to Libya and the Government of Libya. A ground-water reservoir underlies the Bengasi area, in which the water occurs in solution channels, cavities, and other openings in Miocene limestone. The reservoir is recharged directly by rainfall on the area and by infiltration from ephemeral streams (wadis) rising in Al Jabal al Akhar to the east. In the Baninah and Al Fuwayhit areas the ground-water reservoir yields water of fair quality and in sufficient quantity for the current (1959) needs. of the Bengasi city supply. The test-drilling program in the area south and southeast of Bengasi indicates that water in sufficient quantity for additional public supply probably can be obtained in some localities from wells. The water, however, is moderately to highly mineralized and would require treatment or demineralization before it could be used for additional public supply. Much of the water could be used directly for irrigation, but careful attention would have to be given to cultivation, drainage, and cropping practices. The hazard of saltwater encroachment also exists if large-scale withdrawals are undertaken in the coastal zones.

  18. Shale gas impacts on groundwater resources: insights from monitoring a fracking site in Poland

    Science.gov (United States)

    Montcoudiol, Nelly; Isherwood, Catherine; Gunning, Andrew; Kelly, Thomas; Younger, Paul

    2017-04-01

    Exploitation of shale gas by hydraulic fracturing (fracking) is highly controversial and concerns have been raised regarding induced risks from this technique. The SHEER project, an EU Horizon 2020-funded project, is looking into developing best practice to understand, prevent and mitigate the potential short- and long-term environmental impacts and risks from shale gas exploration and exploitation. Three major potential impacts were identified: groundwater contamination, air pollution and induced seismicity. This presentation will deal with the hydrogeological aspect. As part of the SHEER project, four monitoring wells were installed at a shale gas exploration site in Northern Poland. They intercept the main drinking water aquifer located in Quaternary sediments. Baseline monitoring was carried out from mid-December 2015 to beginning of June 2016. Fracking operations occurred in two horizontal wells, in two stages, in June and July 2016. The monitoring has continued after fracking was completed, with site visits every 4-6 weeks. Collected data include measurements of groundwater level, conductivity and temperature at 15-minute intervals, frequent sampling for laboratory analyses and field measurements of groundwater physico-chemical parameters. Groundwater samples are analysed for a range of constituents including dissolved gases and isotopes. The presentation will focus on the interpretation of baseline monitoring data. The insights gained into the behaviour of the Quaternary aquifer will allow a greater perspective to be place on the initial project understanding draw from previous studies. Short-term impacts will also be discussed in comparison with the baseline monitoring results. The presentation will conclude with discussion of challenges regarding monitoring of shale gas fracking sites.

  19. Groundwater resources in Brazil: a review of possible impacts caused by climate change.

    Science.gov (United States)

    Hirata, Ricardo; Conicelli, Bruno P

    2012-06-01

    Groundwater has a strategic role in times of climate change mainly because aquifers can provide water for long periods, even during very long and severe drought. The reduction and/or changes on the precipitation pattern can diminish the recharge mainly in unconfined aquifer, causing available groundwater restriction. The expected impact of long-term climate changes on the Brazilian aquifers for 2050 will lead to a severe reduction in 70% of recharge in the Northeast region aquifers (comparing to 2010 values), varying from 30% to 70% in the North region. Data referring to the South and Southeast regions are more favorable, with an increase in the relative recharge values from 30% to 100%. Another expected impact is the increase in demand and the decrease in the surface water availability that will make the population turn to aquifers as its main source of water for public or private uses in many regions of the country. Thus, an integrated use of surface and groundwater must therefore be considered in the water use planning. The solution of water scarcity is based on three factors: society growth awareness, better knowledge on the characteristics of hydraulic and chemical aquifers and effective management actions.

  20. THE IMPACT OF HUMAN ACTIVITIES ON GROUNDWATER RESOURCES IN THE SOUTH EDGE OF TARIM BASIN, XINJIANG

    Institute of Scientific and Technical Information of China (English)

    2002-01-01

    In the modern times, the population growth, development of industrial and agricultural production andthe petroleum exploitation, brought about the unceasing expansion of artificial oasis and abrupt increase of water demand.The artificial hydraulic irrigation engineering took the place of the natural river system, the reservoirs took the place ofnatural lakes, which in turn enhanced the space-time redistribution of surface water based on the natural evolution, andso did groundwater. The groundwater recharge reduced 26.2% in 46 years from 1950 to 1995 in the southern piedmontflood plain of Tarim Basin due to mean yearly population increase rate of 27.7%0 and associated with the water use rateincreasing from 24. 6% to 58.4%. At the same time the artificial water system seepage give primary play to groundwaterrecharge, which is up to 57.6% whilst that of the natural system reduce to 33.7%. As a result, groundwater level drop3 -5m widespread except some irrigation area and surroundings of plain reservoir. Spring water discharge also reduceabout 37.6% and discharge zone continuously move away to the north with the value of 0. 5 - 1.2km in the past 40years.

  1. Using ERS spaceborne microwave soil moisture observations to predict groundwater head in space and time

    NARCIS (Netherlands)

    Sutanudjaja, E.H.; De Jong, S.M.; Van Geer, F.C.; Bierkens, M.F.P.

    2013-01-01

    The study presented in this paper is to investigate the possibility of using spaceborne remote sensing data for groundwater head prediction. Remotely-sensed soil moisture time series of SWI (Soil Water Index) derived from ERS (European Remote Sensing) scatterometers are used to predict groundwater

  2. Using ERS spaceborne microwave soil moisture observations to predict groundwater heads in space and time

    NARCIS (Netherlands)

    Sutanudjaja, E.H.; Jong, S.M. de; Bierkens, M.F.P.; Geer, F.C. van

    2013-01-01

    The study presented in this paper is to investigate the possibility of using spaceborne remote sensing data for groundwater head prediction. Remotely-sensed soil moisture time series of SWI (Soil Water Index) derived from ERS (European Remote Sensing) scatterometers are used to predict groundwater

  3. The complexity of earth observation valuation: Modeling the patterns and processes of agricultural production and groundwater quality to construct a production possibilities frontier

    Science.gov (United States)

    Forney, W.; Raunikar, R. P.; Bernknopf, R.; Mishra, S.

    2012-12-01

    A production possibilities frontier (PPF) is a graph comparing the production interdependencies for two commodities. In this case, the commodities are defined as the ecosystem services of agricultural production and groundwater quality. This presentation focuses on the refinement of techniques used in an application to estimate the value of remote sensing information. Value of information focuses on the use of uncertain and varying qualities of information within a specific decision-making context for a certain application, which in this case included land use, biogeochemical, hydrogeologic, economic and geospatial data and models. The refined techniques include deriving alternate patterns and processes of ecosystem functions, new estimates of ecosystem service values to construct a PPF, and the extension of this work into decision support systems. We have coupled earth observations of agricultural production with groundwater quality measurements to estimate the value of remote sensing information in northeastern Iowa to be 857M ± 198M (at the 2010 price level) per year. We will present an improved method for modeling crop rotation patterns to include multiple years of rotation, reduction in the assumptions associated with optimal land use allocations, and prioritized improvement of the resolution of input data (for example, soil resources and topography). The prioritization focuses on watersheds that were identified at a coarse-scale of analysis to have higher intensities of agricultural production and lower probabilities of groundwater survivability (in other words, remaining below a regulatory threshold for nitrate pollution) over time, and thus require finer-scaled modeling and analysis. These improved techniques and the simulation of certain scale-dependent policy and management actions, which trade-off the objectives of optimizing crop value versus maintaining potable groundwater, and provide new estimates for the empirical values of the PPF. The calculation

  4. Paleoclimatic and deforestation effect on the chemical and isotopic composition of the coastal fresh groundwater resources of South-east Ivory Coast

    Science.gov (United States)

    Adiaffi, B.; Marlin, C.; Yei, O. M.-S.; Massault, M.; Noret, A.; Biemi, J.

    2009-04-01

    Since a half of century, the forest surface area of the South Ivory Coast has been decreased for the benefit of agriculture (15 000 km2 in 1993 versus 83 000 km2 in 1955-1958). This area also undergoes climate change. Vegetation cover has gradually changed from rainforests (C3 plants) to savanna (C4 plants) and agricultural plants. In the Abidjan area (5.00-6.00°N, 2.40-4.40°W), the mean rainfall amount and temperature value evolve during the 20th century (1912 mm/year and 26.3°C/year during the first decennial to 1613 mm/year and 26.9°C/year during the last ten years). The Paleoproterozoïc fractured bedrock (PB) and the Continental Terminal (CT) deposits groundwater are studied to show the climate change and deforestation effect on the area groundwater resources using stable isotopes (18O, 2H and 13C) contents, radiocarbon (14C) contents and chemical data on a set of 25 groundwater samples. The residence time of the groundwaters is estimated by the 14C using two models: (i) the model of well-mixed reservoir (WMR model) and (ii) the piston flow model (PF model). The range of the PB groundwater residence time (15 000 - 8 000 to ~ 300 - 100 a BP) for both models shows that the recharge has started at the beginning of the post-glacial period whereas the CT aquifer recharge is much more recent (from 300 a BP to today). The PB groundwater provides information about paleoclimatic conditions that occurred over the studied area during the late Pleistocene. It is demonstrated, through this study, that the evolution of vegetation cover (from forests to savanna and agriculture plants) is shown in groundwater by the trend in 13C content from old groundwater (confined bedrock groundwater: residence time of ~ 15 000 a BP) to the recent groundwater (unconfined bedrock groundwater and CT groundwater: residence times: ~ 300 a BP and lower than 100 a BP, respectively). The δ18O and δ2H values also increase with time from the beginning of the post-glacial period (~ 15 000 a BP

  5. Estimation of the groundwater resources of the bedrock aquifers at the Kettle Moraine Springs State Fish Hatchery, Sheboygan County, Wisconsin

    Science.gov (United States)

    Dunning, Charles; Feinstein, Daniel T.; Buchwald, Cheryl A.; Hunt, Randall J.; Haserodt, Megan

    2017-10-12

    Groundwater resources information was needed to understand regional aquifer systems and water available to wells and springs for rearing important Lake Michigan fish species at the Kettle Moraine Springs State Fish Hatchery in Sheboygan County, Wisconsin. As a basis for estimating the groundwater resources available, an existing groundwater-flow model was refined, and new groundwater-flow models were developed for the Kettle Moraine Springs State Fish Hatchery area using the U.S. Geological Survey (USGS) finite-difference code MODFLOW. This report describes the origin and construction of these groundwater-flow models and their use in testing conceptual models and simulating the hydrogeologic system.The study area is in the Eastern Ridges and Lowlands geographical province of Wisconsin, and the hatchery property is situated on the southeastern edge of the Kettle Moraine, a north-south trending topographic high of glacial origin. The bedrock units underlying the study area consist of Cambrian, Ordovician, and Silurian units of carbonate and siliciclastic lithology. In the Sheboygan County area, the sedimentary bedrock sequence reaches a thickness of as much as about 1,600 feet (ft).Two aquifer systems are present at the Kettle Moraine Springs State Fish Hatchery. A shallow system is made up of Silurian bedrock, consisting chiefly of dolomite, overlain by unconsolidated Quaternary-age glacial deposits. The glacial deposits of this aquifer system are the typical source of water to local springs, including the springs that have historically supplied the hatchery. The shallow aquifer system, therefore, consists of the unconsolidated glacial aquifer and the underlying bedrock Silurian aquifer. Most residential wells in the area draw from the Silurian aquifer. A deeper confined aquifer system is made up of Cambrian- and Ordovician-age bedrock units including sandstone formations. Because of its depth, very few wells are completed in the Cambrian-Ordovician aquifer system

  6. Modeling climate change impacts on groundwater resources using transient stochastic climatic scenarios

    Science.gov (United States)

    Goderniaux, Pascal; BrouyèRe, Serge; Blenkinsop, Stephen; Burton, Aidan; Fowler, Hayley J.; Orban, Philippe; Dassargues, Alain

    2011-12-01

    Several studies have highlighted the potential negative impact of climate change on groundwater reserves, but additional work is required to help water managers plan for future changes. In particular, existing studies provide projections for a stationary climate representative of the end of the century, although information is demanded for the near future. Such time-slice experiments fail to account for the transient nature of climatic changes over the century. Moreover, uncertainty linked to natural climate variability is not explicitly considered in previous studies. In this study we substantially improve upon the state-of-the-art by using a sophisticated transient weather generator in combination with an integrated surface-subsurface hydrological model (Geer basin, Belgium) developed with the finite element modeling software "HydroGeoSphere." This version of the weather generator enables the stochastic generation of large numbers of equiprobable climatic time series, representing transient climate change, and used to assess impacts in a probabilistic way. For the Geer basin, 30 equiprobable climate change scenarios from 2010 to 2085 have been generated for each of six different regional climate models (RCMs). Results show that although the 95% confidence intervals calculated around projected groundwater levels remain large, the climate change signal becomes stronger than that of natural climate variability by 2085. Additionally, the weather generator's ability to simulate transient climate change enabled the assessment of the likely time scale and associated uncertainty of a specific impact, providing managers with additional information when planning further investment. This methodology constitutes a real improvement in the field of groundwater projections under climate change conditions.

  7. Evaluation of groundwater resources of the Chesapeake Bay Watershed using an integrated hydrologic model

    Science.gov (United States)

    Seck, A.; Welty, C.; Maxwell, R. M.

    2013-12-01

    We present results from a distributed integrated hydrologic model of the Chesapeake Bay Watershed using ParFlow-CLM. The model covers an area of 400,000 km2 spanning five physiographic provinces, discretized at a horizontal resolution of 2 km and vertical resolution of 5 m. Synthesis of published hydrogeologic data as well as analysis of well completion reports from state agencies were used to construct a hydrogeologic model framework. The model was run for the period of 2003-2004 using National Land Data Assimilation System (NLDAS) meteorological forcing. Model output captures seasonal and spatial variability in subsurface storage and surface storage, and produces water table depths consistent with the topography, meteorological forcing, and hydrogeological setting. Model results show spatial variability in evaporation fluxes correlated to land cover at higher resolution than either NLDAS outputs or the EPA Chesapeake Bay Watershed Model Phase 5.3. Comparison with USGS streamflow data at selected stream gages shows good agreement in daily discharge timing and fluxes for high and average flows, whereas the model does not perform as well for low flows during summer and dry periods. Analysis of groundwater stores and fluxes showed marked variability across physiographic provinces. Highest groundwater stores were expectedly found in the Coastal Plain, while the Blue Ridge physiographic province had the lowest stores. The Appalachian Plateau was characterized by the highest net recharge rates. The highest discharge rates were found in the Valley and Ridge, Piedmont and Coastal Plain. The construction of this model constitutes a step forward in understanding the groundwater system in the Chesapeake Bay Watershed and its role in solute delivery to the Chesapeake Bay.

  8. Geology and ground-water resources of Goshen County, Wyoming; Chemical quality of the ground water

    Science.gov (United States)

    Rapp, J.R.; Visher, F.N.; Littleton, R.T.; Durum, W.H.

    1957-01-01

    Goshen County, which has an area of 2,186 square miles, lies in southeastern Wyoming. The purpose of this study was to evaluate the ground-water resources of the county by determining the character, thickness, and extent of the waterbearing materials; the source, occurrence, movement, quantity, and quality of the ground water; and the possibility of developing additional ground water. The rocks exposed in the area are sedimentary and range in age from Precambrian to Recent. A map that shows the areas of outcrop and a generalized section that summarizes the age, thickness, physical character, and water supply of these formations are included in the report. Owing to the great depths at which they lie beneath most of the county, the formations older than the Lance formation of Late Cretaceous age are not discussed in detail. The Lance formation, of Late Cretaceous age, which consists mainly of beds of fine-grained sandstone and shale, has a maximum thickness of about 1,400 feet. It yields water, which usually is under artesian pressure, to a large number of domestic and stock wells in the south-central part of the county. Tertiary rocks in the area include the Chadron and Brule formations of Oligocene age, the Arikaree formation of Miocene age, and channel deposits of Pliocene age. The Chadron formation is made up of two distinct units: a lower unit of highly variegated fluviatile deposits that has been found only in the report area; and an upper unit that is typical of the formation as it occurs in adjacent areas. The lower unit, which ranges in thickness from a knife edge to about 95 feet, is not known to yield water to wells, but its coarse-grained channel deposits probably would yield small quantities of water to wells. The upper unit, which ranges in thickness from a knife edge to about 150 feet, yields sufficient quantities of water for domestic and stock uses from channel deposits of sandstone under artesian pressure. The Brule formation, which is mainly a

  9. Municipal Landfilling Practice And Its Impact On Groundwater Resources In And Around Urban Toronto, Canada

    Science.gov (United States)

    Howard, K. W. F.; Eyles, N.; Livingstone, S.

    1996-01-01

    The hazardous contents of municipal landfills are rarely documented and problems are usually not recognised until landfill leachate pollutes a well or surface-water body. By this time, the groundwater is often extensively contaminated with little opportunity for redress. Recent studies in southern Ontario have adopted a pro-active stance to this issue. The location, size, design and geologic setting of almost 1,200 active and inactive landfills have been documented; in addition, a contaminant-source audit has been performed for a representative region of urban Toronto, where 82 landfills sites are contained in an area of 700 km2. Groundwater flow modeling reveals that at half the sites groundwater travel time to major urban streams and Lake Ontario is less than 10 years, suggesting that chemically conservative chemicals released at these sites would have a rapid impact on surface-water quality. The sites are as large as 99 ha, and waste thickness normally ranges from 3-30 m. In the audited area, the sites contain an estimated 4.6×107 tons of material, consisting primarily of domestic waste, incinerator ashes, and construction and commercial debris; some sites are believed, however, to have received liquid waste from industrial sources. The chemical audit indicates that more than 1.3 million tons, or approximately 2.9 percent of the landfill waste, will enter the landfill leachate. About 99 percent of the leachable mass is composed of calcium, magnesium, sodium, nitrogen (as ammonia, nitrate, and nitrite), chloride, sulphate, and bicarbonate. However, the real potential damage must be measured by the degree of environmental degradation that would ensue if the leachate is released to the subsurface. Ignoring the possible effects of chemical biodegradation and volatilization within the aquifer, calculations indicate that 17 of the 39 leachate components investigated are individually capable of contaminating at least 2×1012 liters of water in excess of Provincial

  10. A multi-method approach for groundwater resource assessment in coastal carbonate (karst) aquifers: the case study of Sierra Almijara (southern Spain)

    Science.gov (United States)

    Andreo, B.; Barberá, J. A.; Mudarra, M.; Marín, A. I.; García-Orellana, J.; Rodellas, V.; Pérez, I.

    2017-08-01

    Understanding the transference of water resources within hydrogeological systems, particularly in coastal aquifers, in which groundwater discharge may occur through multiple pathways (through springs, into rivers and streams, towards the sea, etc.), is crucial for sustainable groundwater use. This research aims to demonstrate the usefulness of the application of conventional recharge assessment methods coupled to isotopic techniques for accurately quantifying the hydrogeological balance and submarine groundwater discharge (SGD) from coastal carbonate aquifers. Sierra Almijara (Southern Spain), a carbonate aquifer formed of Triassic marbles, is considered as representative of Mediterranean coastal karst formations. The use of a multi-method approach has permitted the computation of a wide range of groundwater infiltration rates (17-60%) by means of direct application of hydrometeorological methods (Thornthwaite and Kessler) and spatially distributed information (modified APLIS method). A spatially weighted recharge rate of 42% results from the most coherent information on physiographic and hydrogeological characteristics of the studied system. Natural aquifer discharge and groundwater abstraction have been volumetrically quantified, based on flow and water-level data, while the relevance of SGD was estimated from the spatial analysis of salinity, 222Rn and the short-lived radium isotope 224Ra in coastal seawater. The total mean aquifer discharge (44.9-45.9 hm3 year-1) is in agreement with the average recharged groundwater (44.7 hm3 year-1), given that the system is volumetrically equilibrated during the study period. Besides the groundwater resources assessment, the methodological aspects of this research may be interesting for groundwater management and protection strategies in coastal areas, particularly karst environments.

  11. Global-scale modeling of groundwater recharge

    Science.gov (United States)

    Döll, P.; Fiedler, K.

    2008-05-01

    Long-term average groundwater recharge, which is equivalent to renewable groundwater resources, is the major limiting factor for the sustainable use of groundwater. Compared to surface water resources, groundwater resources are more protected from pollution, and their use is less restricted by seasonal and inter-annual flow variations. To support water management in a globalized world, it is necessary to estimate groundwater recharge at the global scale. Here, we present a best estimate of global-scale long-term average diffuse groundwater recharge (i.e. renewable groundwater resources) that has been calculated by the most recent version of the WaterGAP Global Hydrology Model WGHM (spatial resolution of 0.5° by 0.5°, daily time steps). The estimate was obtained using two state-of-the-art global data sets of gridded observed precipitation that we corrected for measurement errors, which also allowed to quantify the uncertainty due to these equally uncertain data sets. The standard WGHM groundwater recharge algorithm was modified for semi-arid and arid regions, based on independent estimates of diffuse groundwater recharge, which lead to an unbiased estimation of groundwater recharge in these regions. WGHM was tuned against observed long-term average river discharge at 1235 gauging stations by adjusting, individually for each basin, the partitioning of precipitation into evapotranspiration and total runoff. We estimate that global groundwater recharge was 12 666 km3/yr for the climate normal 1961-1990, i.e. 32% of total renewable water resources. In semi-arid and arid regions, mountainous regions, permafrost regions and in the Asian Monsoon region, groundwater recharge accounts for a lower fraction of total runoff, which makes these regions particularly vulnerable to seasonal and inter-annual precipitation variability and water pollution. Average per-capita renewable groundwater resources of countries vary between 8 m3/(capita yr) for Egypt to more than 1 million m3

  12. Altitude, age, and quality of groundwater, Papio-Missouri River Natural Resources District, eastern Nebraska, 1992 to 2009

    Science.gov (United States)

    McGuire, Virginia L.; Ryter, Derek W.; Flynn, Amanda S.

    2012-01-01

    The U.S. Geological Survey, in cooperation with the Papio-Missouri River Natural Resources District (PMRNRD), conducted this study to map the water-level altitude of 2009 within the Elkhorn River Valley, Missouri River Valley, and Platte River Valley alluvial aquifers; to present the predevelopment potentiometric-surface altitude within the Dakota aquifer; and to describe the age and quality of groundwater in the five principal aquifers of the PMRNRD in eastern Nebraska using data collected from 1992 to 2009. In addition, implications of alternatives to the current PMRNRD groundwater-quality monitoring approach are discussed. In the PMRNRD, groundwater altitude, relative to National Geodetic Vertical Datum of 1929, ranged from about 1,080 feet (ft) to 1,180 ft in the Elkhorn River Valley alluvial aquifer and from about 960 ft to 1,080 ft in the Missouri River Valley and Platte River Valley alluvial aquifers. In the PMRNRD, the estimated altitude of the potentiometric surface of the Dakota aquifer, predevelopment, ranged from about 1,100 ft to 1,200 ft. To assess groundwater age and quality, groundwater samples were collected from a total of 217 wells from 1992 to 2009 for analysis of various analytes. Groundwater samples collected in the PMRNRD from 1992 to 2009 and interpreted in this report were analyzed for age-dating analytes (chlorofluorocarbons), dissolved gases, major ions, trace elements, nutrients, stable isotope ratios, pesticides and pesticide degradates, volatile organic compounds, explosives, and 222radon. Apparent groundwater age was estimated from concentrations of chlorofluorocarbons measured in samples collected in 2000. Apparent groundwater-recharge dates ranged from older than 1940 in samples from wells screened in the Missouri River Valley alluvial aquifer to the early 1980s in samples from wells screened in the Dakota aquifer. Concentrations of major ions in the most recent sample per well collected from 1992 to 2009 indicate that the

  13. Nitrate fluxes to groundwater under citrus orchards in a Mediterranean climate: observations, calibrated models, simulations and agro-hydrological conclusions.

    Science.gov (United States)

    Kurtzman, Daniel; Shapira, Roi H; Bar-Tal, Asher; Fine, Pinchas; Russo, David

    2013-08-01

    Nitrate contamination of groundwater under land used for intensive-agriculture is probably the most worrisome agro-hydrological sustainability problem worldwide. Vadose-zone samples from 0 to 9 m depth under citrus orchards overlying an unconfined aquifer were analyzed for variables controlling water flow and the fate and transport of nitrogen fertilizers. Steady-state estimates of water and NO3-N fluxes to groundwater were found to vary spatially in the ranges of 90-330 mm yr(-1) and 50-220 kg ha(-1) yr(-1), respectively. Calibration of transient models to two selected vadose-zone profiles required limiting the concentration of NO3-N in the solution that is taken up by the roots to 30 mg L(-1). Results of an independent lysimeter experiment showed a similar nitrogen-uptake regime. Simulations of past conditions revealed a significant correlation between NO3-N flux to groundwater and the previous year's precipitation. Simulations of different nitrogen-application rates showed that using half of the nitrogen fertilizer added to the irrigation water by farmers would reduce average NO3-N flux to groundwater by 70%, decrease root nitrogen uptake by 20% and reduce the average pore water NO3-N concentration in the deep vadose zone to below the Israeli drinking water standard; hence this rate of nitrogen application was found to be agro-hydrologically sustainable. Beyond the investigation of nitrate fluxes to groundwater under citrus orchards and the interesting case-study aspects, this work demonstrates a methodology that enables skillful decisions concerning joint sustainability of both the water resource and agricultural production in a common environmental setting.

  14. Remedial action plan and site design for stabilization of the inactive uranium processing site at Naturita, Colorado. Appendix B of Attachment 3: Groundwater hydrology report, Attachment 4: Water resources protection strategy, Final

    Energy Technology Data Exchange (ETDEWEB)

    1994-03-01

    Attachment 3 Groundwater Hydrology Report describes the hydrogeology, water quality, and water resources at the processing site and Dry Flats disposal site. The Hydrological Services calculations contained in Appendix A of Attachment 3, are presented in a separate report. Attachment 4 Water Resources Protection Strategy describes how the remedial action will be in compliance with the proposed EPA groundwater standards.

  15. Ground-water resources of coastal Citrus, Hernando, and southwestern Levy counties, Florida

    Science.gov (United States)

    Fretwell, J.D.

    1983-01-01

    Ground water in the coastal parts of Citrus, Hernando, and Levy Counties is obtained almost entirely from the Floridan aquifer. The aquifer is unconfined near the coast and semiconfined in the ridge area. Transmissivity ranges from 20,000 feet squared per day in the ridge area to greater than 2,000,000 feet squared per day near major springs. Changes in the potentiometric surface of the aquifer are small between the wet and dry seasons. Water quality within the study area is generally very good except immediately adjacent to the coast where saltwater from the Gulf of Mexico poses a threat to freshwater supply. This threat can be compensated for by placing well fields a sufficient distance away from the zone of transition from saltwater to freshwater so as not to reduce or reverse the hydraulic gradient in that zone. Computer models are presently available to help predict the extent of influence of ground-water withdrawals in an area. These may be used as management tools in planning ground-water development of the area. (USGS)

  16. Analytical Modelling of Rainwater Harvesting and Groundwater Resources in Auchi, Nigeria

    Directory of Open Access Journals (Sweden)

    Olotu Yahaya

    2014-07-01

    Full Text Available Shortage in supply of water for potable and non-potable applications and exponential world population increase is a strong constrain to Human Development Index and social-economic advancement in Nigeria. ClimGen (Version 4.1.05 was used to simulate and create large dataset of annual rainfall depth. Generated average annual rainfall from 1430 mm to 1600 mm was subjected to varying roof plan surfaces of 250 m2 ; 500 m2 ; 1000 m2 ; and 2000 m2 respectively. Simulation analysis showed that an average of 5,300m 3 of rainwater was harvestable and this value of water could only meet water demand of 170 people annually. The relationship of roof plan surface (RPS and collected rainwater is very strong with R 2= 0.84 and 0.95 respectively. Again, the volume of groundwater withdrawal increased from 12.4×10 4 m 3 to 32.7×10 4 m 3 , this could only meet an annual water demand for 10,480 people representing about 6.2% of the population in Auchi. This development reveals that water supply from the alternative sources could not meet up to 6.3% of total water demand in Auchi and increasing water availability and accessibility to about 65% (31.3×105m3 coverage requires integrated rainwater harvesting system and technically-based groundwater exploration mechanism.

  17. Ground-water resources in the vicinity of the Crown Point fish hatchery, Essex County, New York

    Science.gov (United States)

    Kantrowitz, I.H.

    1968-01-01

    The Crown Point Fish Hatchery, one of several hatcheries operated by the New York State Conservation Department, is located in Crown Point Center, Essex County, on the eastern edge of the Adirondack Highlands and about 2 miles west of lake Champlain. Figure 1 is a location map of the vicinity of the Hatchery. This report summarizes an investigation by the U.S. Geological Survey, in cooperation with the New York State Conservation Department, Division of Water Resources, to locate and evaluate sources of additional ground-water supply for the Hatchery. In order to expand the facilities at the Hatchery, an additional water supply of about 100 gpm (gallons per minute) to as much as 350 gpm is needed. In addition, the type of fish culture practiced requires a water temperature of about 7 to 13 degrees Celsius (centigrade) for optimum results.

  18. Challenges in groundwater resource management in coastal aquifers of East Africa: Investigations and lessons learnt in the Comoros Islands, Kenya and Tanzania

    Directory of Open Access Journals (Sweden)

    Jean-Christophe Comte

    2016-03-01

    New hydrological insights: Results confirm the fundamental importance of coastal groundwater resources for the development of the region and the urgent need to match groundwater development with demographic and economic growth. Hydrogeological knowledge is fragmented, groundwater lacks a long-term monitoring infrastructure and information transfer from stakeholders to users is limited. Current trends in demography, climate, sea-level and land-use are further threatening freshwater availability. Despite possessing high-productivity aquifers, water quality from wells and boreholes is generally impacted by saltwater intrusion. Shallow large-diameter wells, following the traditional model of these areas, consistently prove to be less saline and more durable than deeper small-diameter boreholes. However, promoting the use of large numbers of shallow wells poses a significant challenge for governance, requiring coherent management of the resource at local and national scales and the engagement of local communities.

  19. Geophysical, isotopic, and hydrogeochemical tools to identify potential impacts on coastal groundwater resources from Urmia hypersaline Lake, NW Iran.

    Science.gov (United States)

    Amiri, Vahab; Nakhaei, Mohammad; Lak, Razyeh; Kholghi, Majid

    2016-08-01

    hydraulic conductivity. These properties enhance the salinization of groundwater observed in the study area. The main factors influencing the salinity are base-exchange reactions, invasion of highly diluted saltwater, dissolution of salty pans, and water chemistry evolution along flow paths.

  20. Brackish groundwater in the United States

    Science.gov (United States)

    Stanton, Jennifer S.; Anning, David W.; Brown, Craig J.; Moore, Richard B.; McGuire, Virginia L.; Qi, Sharon L.; Harris, Alta C.; Dennehy, Kevin F.; McMahon, Peter B.; Degnan, James R.; Böhlke, John Karl

    2017-04-05

    in the United States. Previously published digital data relating to brackish groundwater resources were limited to a small number of State- and regional-level studies. Data sources for this assessment ranged from single publications to large datasets and from local studies to national assessments. Geochemical data included concentrations of dissolved solids, major ions, trace elements, nutrients, and radionuclides as well as physical properties of the water (pH, temperature, and specific conductance). Additionally, the database provides selected well information (location, yield, depth, and contributing aquifer) necessary for evaluating the water resource.The assessment was divided into national-, regional-, and aquifer-scale analyses. National-scale analyses included evaluation of the three-dimensional distribution of observed dissolved-solids concentrations in groundwater, the three-dimensional probability of brackish groundwater occurrence, and the geochemical characteristics of saline (greater than or equal to 1,000 mg/L of dissolved solids) groundwater resources. Regional-scale analyses included a summary of the percentage of observed grid cell volume in the region that was occupied by brackish groundwater within the mixture of air, water, and rock for multiple depth intervals. Aquifer-scale analyses focused primarily on four regions that contained the largest amounts of observed brackish groundwater and included a generalized description of hydrogeologic characteristics from previously published work; the distribution of dissolved-solids concentrations; considerations for developing brackish groundwater resources, including a summary of other chemical characteristics that may limit the use of brackish groundwater and the ability of sampled wells producing brackish groundwater to yield useful amounts of water; and the amount of saline groundwater being used in 2010.

  1. Wave energy resource assessment based on satellite observations around Indonesia

    Science.gov (United States)

    Ribal, Agustinus; Zieger, Stefan

    2016-06-01

    A preliminary assessment of wave energy resource around Indonesian's ocean has been carried out by means of analyzing satellite observations. The wave energy flux or wave power can be approximated using parameterized sea states. Wave power scales with significant wave height, characteristic wave period and water depth. In this approach, the significant wave heights were obtained from ENVISAT (Environmental Satellite) data which have been calibrated. However, as the characteristic wave period is rarely specified and therefore must be estimated from other variables when information about the wave spectra is unknown. Here, the characteristic wave period was calculated with an empirical model that utilizes altimeter estimates of wave height and backscatter coefficient originally proposed. For the Indonesian region, wave power energy is calculated over two periods of one year each and was compared with the results from global hindcast carried out with a recent release of wave model WAVEWATCH III. We found that, the most promising wave power energy regions around the Indonesian archipelago are located in the south of Java island and the south west of Sumatera island. In these locations, about 20 - 30 kW/m (90th percentile: 30-50 kW/m, 99th percentile: 40-60 kW/m) wave power energy on average has been found around south of Java island during 2010. Similar results have been found during 2011 at the same locations. Some small areas which are located around north of Irian Jaya (West Papua) are also very promising and need further investigation to determine its capacity as a wave energy resource.

  2. Observations of nearshore groundwater discharge: Kahekili Beach Park submarine springs, Maui, Hawaii

    Science.gov (United States)

    Swarzenski, Peter W.; Dulai, H.; Kroeger, K.D.; Smith, C.G.; Dimova, N.; Storlazzi, C. D.; Prouty, N.G.; Gingerich, S.B.; Glenn, C. R.

    2016-01-01

    Study regionThe study region encompasses the nearshore, coastal waters off west Maui, Hawaii. Here abundant groundwater—that carries with it a strong land-based fingerprint—discharges into the coastal waters and over a coral reef.Study focusCoastal groundwater discharge is a ubiquitous hydrologic feature that has been shown to impact nearshore ecosystems and material budgets. A unique combined geochemical tracer and oceanographic time-series study addressed rates and oceanic forcings of submarine groundwater discharge at a submarine spring site off west Maui, Hawaii.New hydrological insights for the regionEstimates of submarine groundwater discharge were derived for a primary vent site and surrounding coastal waters off west Maui, Hawaii using an excess 222Rn (t1/2 = 3.8 d) mass balance model. Such estimates were complemented with a novel thoron (220Rn,t1/2 = 56 s) groundwater discharge tracer application, as well as oceanographic time series and thermal infrared imagery analyses. In combination, this suite of techniques provides new insight into the connectivity of the coastal aquifer with the near-shore ocean and examines the physical drivers of submarine groundwater discharge. Lastly, submarine groundwater discharge derived constituent concentrations were tabulated and compared to surrounding seawater concentrations. Such work has implications for the management of coastal aquifers and downstream nearshore ecosystems that respond to sustained constituent loadings via this submarine route.

  3. Climate change impacts on groundwater resources: modelled deficits in a chalky aquifer, Geer basin, Belgium

    Science.gov (United States)

    Brouyère, Serge; Carabin, Guy; Dassargues, Alain

    An integrated hydrological model (MOHISE) was developed in order to study the impact of climate change on the hydrological cycle in representative water basins in Belgium. This model considers most hydrological processes in a physically consistent way, more particularly groundwater flows which are modelled using a spatially distributed, finite-element approach. Thanks to this accurate numerical tool, after detailed calibration and validation, quantitative interpretations can be drawn from the groundwater model results. Considering IPCC climate change scenarios, the integrated approach was applied to evaluate the impact of climate change on the water cycle in the Geer basin in Belgium. The groundwater model is described in detail, and results are discussed in terms of climate change impact on the evolution of groundwater levels and groundwater reserves. From the modelling application on the Geer basin, it appears that, on a pluri-annual basis, most tested scenarios predict a decrease in groundwater levels and reserves in relation to variations in climatic conditions. However, for this aquifer, the tested scenarios show no enhancement of the seasonal changes in groundwater levels. Un modèle hydrologique intégré (MOHISE) a été développé afin d'étudier l'impact du changement climatique sur le cycle hydrologique de bassins versants représentatifs de Belgique. Ce modèle prend en compte tous les processus hydrologiques d'une manière physiquement consistante, plus particulièrement les écoulements souterrains qui sont modélisés par une approche spatialement distribuée aux éléments finis. Grâce à cet outil numérique précis, après une calibration et une validation détaillées, des interprétations quantitatives peuvent être réalisées à partir des résultats du modèle de nappe. Considérant des scénarios de changements climatiques de l'IPCC, l'approche intégrée a été appliquée pour évaluer l'impact du changement climatique sur le cycle de l

  4. Ground-water resources in the vicinity of Cortland, Trumbull County, Ohio

    Science.gov (United States)

    Barton, G.J.; Wright, P.R.

    1997-01-01

    The city of Cortland lies on the southeast ern shoreline of the 12.3-square-mile Mosquito Creek Lake in Trumbull County, Ohio. Cortland relies upon public wells completed in the Cussewago Sandstone for potable water. The Cussewago Sandstone, the principal aquifer in the study area, is a subcrop of the glaciofluvial sediments in the lake; the unit dips gently towards the southeast. Thickness of the Cussewago Sandstone ranges from less than 20 feet in south-central Bazetta Township to 152 feet in Cortland. The Bedford Shale overlies and confines the Cussewago Sandstone and separates it hydraulically from the Berea Sandstone. The Bedford Shale and Berea Sandstone are not a prolific source of ground water. In places, the Bedford Shale was completely eroded away prior to deposition of the Berea Sandstone. Where the Bedford Shale is absent, such as at the City of Cortland North Well Field, the Berea Sandstone and Cussewago Sandstone are likely in hydraulic connection. Throughout most of the study area, the Cussewago Sandstone is a confined aquifer. Ground-water flow is to the east and southeast. Pumping at both Cortland well fields has created cones of depression in the potentiometric surface. These cones of depression cause a local reversal in ground-water flow immediately east of both well fields. The absence of detectable concentrations of tritium in water samples from wells completed in the Cussewago Sandstone at Cortland indicates that ground water predates the atmospheric nuclear testing of the 1950's. Ground water requires about 60 to 110 years to flow from the Cussewago Sandstone subcrop of the glaciofluvial sediments in the lake to the Cortland public-supply wells. A comparison of aquifer storage and pumpage in the study area shows that the Cussewago Sandstone receives adequate recharge to support current withdrawals by Cortland public-supply wells. In the immediate vicinity of Cortland- between Route 305 and the Bazetta-Mecca Town ship line and between the

  5. A review of seawater intrusion in the Nile Delta groundwater system – the basis for assessing impacts due to climate changes and water resources development

    NARCIS (Netherlands)

    Mabrouk, M.B.; Jonoski, A.; Solomatine, D.P.; Uhlenbrook, S.

    2013-01-01

    Serious environmental problems are emerging in the River Nile basin and its groundwater resources. Recent years have brought scientific evidence of climate change and development-induced environmental impacts globally as well as over Egypt. Some impacts are subtle, like decline of the Nile River wat

  6. Geology and ground-water resources of the Big Sandy Creek Valley, Lincoln, Cheyenne, and Kiowa Counties, Colorado; with a section on Chemical quality of the ground water

    Science.gov (United States)

    Coffin, Donald L.; Horr, Clarence Albert

    1967-01-01

    This report describes the geology and ground-water resources of that part of the Big Sandy Creek valley from about 6 miles east of Limon, Colo., downstream to the Kiowa County and Prowers County line, an area of about 1,400 square miles. The valley is drained by Big Sandy Creek and its principal tributary, Rush Creek. The land surface ranges from flat to rolling; the most irregular topography is in the sandhills south and west of Big Sandy Creek. Farming and livestock raising are the principal occupations. Irrigated lands constitute only a sin311 part of the project area, but during the last 15 years irrigation has expanded. Exposed rocks range in age from Late Cretaceous to Recent. They comprise the Carlile Shale, Niobrara Formations, Pierre Shale (all Late Cretaceous), upland deposits (Pleistocene), valley-fill deposits (Pleistocene and Recent), and dune sand (Pleistocene and Recent). Because the Upper Cretaceous formations are relatively impermeable and inhibit water movement, they allow ground water to accumul3te in the overlying unconsolidated Pleistocene and Recent deposits. The valley-fill deposits constitute the major aquifer and yield as much as 800 gpm (gallons per mixture) to wells along Big Sandy and Rush Creeks. Transmissibilities average about 45,000 gallons per day per foot. Maximum well yields in the tributary valleys are about 200 gpm and average 5 to 10 gpm. The dune sand and upland deposits generally are drained and yield water to wells in only a few places. The ground-water reservoir is recharged only from direct infiltration of precipitation, which annually averages about 12 inches for the entire basin, and from infiltration of floodwater. Floods in the ephemeral Big Sandy Creek are a major source of recharge to ground-water reservoirs. Observations of a flood near Kit Carson indicated that about 3 acre-feet of runoff percolated into the ground-water reservoir through each acre of the wetted stream channel The downstream decrease in channel and

  7. Summary appraisals of the Nation's ground-water resources; California region

    Science.gov (United States)

    Thomas, H.E.; Phoenix, D.A.

    1976-01-01

    Most people in the California Region live in a semiarid or arid climate, with precipitation less than the potential evapotranspiration- environments of perennial water deficiency. The deficiency becomes most onerous during the characteristically rainless summers and during recurrent droughts that may continue for 10--20 years. However, water from winter rain and snow can be stored for use during the dry summer months, and water stored during a wet climatic period can be used in a succeeding dry period; moreover, perennial deficiency can be overcome by bringing water from areas of perennial surplus. Ground-water reservoirs have especial significance in arid and semiarid regions as repositories where water is stored or can be stored with minimum loss by evaporation.

  8. Modeling Groundwater and Return Flow in an Integrated Framework to Investigate the Resilience of U.S. Water Resources in the Future

    Science.gov (United States)

    Voisin, N.; Leung, L. R.; Hejazi, M. I.; Liu, L.; Huang, M.; Li, H. Y.; Tesfa, T. K.

    2014-12-01

    To advance understanding of the interactions between human activities and the water cycle, an integrated terrestrial water cycle component has been added to an Earth system model. This includes a land surface model fully coupled to a river routing model and generic water management model applicable globally at 1/2o resolution and regionally at 1/8o resolution. A global integrated assessment model and its regionalized version for the U.S. are used to simulate water demand consistent with the energy technology and socio-economics scenarios. Human influence on the hydrologic cycle includes regulation and storage, consumptive use and overall redistribution of water resources in space and time. As groundwater provides an important source of water supply for irrigation and other uses worldwide, the integrated modeling framework has been extended to represent groundwater as an additional supply source, and to account for the return flow generated from the groundwater and surface water withdrawals. In this presentation, we evaluate the groundwater supply and return flow modules by analyzing the simulated regulated flow, reservoir storage and supply deficit for irrigation and non irrigation sectors over major hydrologic regions of the conterminous U.S. The modeling framework is then used to provide insights on the resilience of future water resources in the U.S. ensured specifically by the return flow and groundwater dependence.

  9. Assessing the spatial variability of constraints on groundwater abstractions due to potential adverse resource impacts on surface water ecosystems - a GIS based approach

    Science.gov (United States)

    Watson, K. A.; Mayer, A. S.; Reeves, H. W.

    2010-12-01

    Groundwater contributions to streams, particularly in periods of low flow, can be critical to sustaining aquatic ecosystems. Groundwater abstractions in areas where the groundwater is in hydraulic connection with the surface water can deplete these flows potentially causing adverse resource impacts. In particular, the passage of the Great Lakes—St. Lawrence Basin Water Resources Compact in 2008 has brought increasing awareness to this issue in the Great Lakes Basin. As a requirement of this legislation, each of the Great Lakes States must take steps to limit water withdrawals that may potentially impact water-dependent natural resources. The State of Michigan has developed an automated “Water Withdrawal Assessment Tool” to assist in this process. By using the methodology as developed for the Michigan Water Withdrawal Assessment Tool, this study examines spatial variations in maximum allowable pumping rates under these constraints. The pumping rates are constrained either by the local hydrogeology or concerns related to adverse impacts to the surface water ecosystems. A simple analytical model is used to calculate streamflow depletion as a function of hypothetical groundwater abstraction rates and positions. The inputs to this model are obtained from a GIS database including such spatially relevant information as aquifer characteristics, streamflows, and a stream network. The maximum pumping rates are averaged over the HUC-8 watershed scale. We explore the characteristics that play the largest role in the variability of maximum pumping rates, such as hydrogeologic parameters, stream density, and stream flows. We also discuss limitations of the analytical approach to assessing water availability. Understanding how these restrictions on adverse resource impacts constrain groundwater usage and which hydrogeologic characteristics and spatial variables have the most influence on potential streamflow depletions have important water resources policy and management

  10. A Use Case for implementing Earth observation (EO) to avoid regional groundwater contamination in the Midwest US

    Science.gov (United States)

    Bernknopf, R.; Pearlman, J.

    2016-12-01

    A use case to implement Landsat data for application in decisions in the agricultural sector is being developed. Stakeholders are at both the farm level and regional level. Decisions by individual farmers and communities about the intensity of use of agrochemicals on crops can affect the future quality of the groundwater in Iowa. An initial case study was completed to examine some of the technical perspectives of adapting and coupling satellite imagery and in situ water quality measurements to forecast changes in groundwater quality. This analysis was conducted to identify the benefits of EO to assist in specific decisions to improve agricultural land management and regulation of groundwater contamination. Results demonstrated that Landsat information facilitates spatiotemporal analysis of the impact of nitrates on groundwater resources. Value is dependent on whether additional information reduces the variance (uncertainty) in outcomes. The use case ultimately involves scientific experts, farmers and their representatives, and the Government. Decisions involve some level of uncertainty in scientific measurement and statistical variability affects its informational value. These issues are concerns with implementing remote sensing technology and must be examined with end users and their impact discussed and understood. Thus, the study team held meetings with subject experts from Iowa State University and the Iowa Farm Bureau to explore the next steps in developing the use case. Discussion with the subject experts focused on more detail to capture new agricultural science advances and engineering options that could be linked in a multi-scale approach. A second meeting between the study and the Iowa Farm Bureau centered on the need for efficient regulation of land use and regulation of agrochemical application in the Midwest. The impacts of these discussions and other user inputs on the directions of the use case will be presented.

  11. Global modeling of withdrawal, allocation and consumptive use of surface water and groundwater resources

    NARCIS (Netherlands)

    Wada, Y.; Wisser, D.; Bierkens, M. F. P.

    2014-01-01

    To sustain growing food demand and increasing standard of living, global water withdrawal and consumptive water use have been increasing rapidly. To analyze the human perturbation on water resources consistently over large scales, a number of macro-scale hydrological models (MHMs) have been develope

  12. Global modeling of withdrawal, allocation and consumptive use of surface water and groundwater resources

    NARCIS (Netherlands)

    Wada, Y.; Wisser, D.; Bierkens, M.F.P.

    2013-01-01

    To sustain growing food demand and increasing standard of living, global water withdrawal and consumptive water use have been increasing rapidly. To analyze the human perturbation on water resources consistently over a large scale, a number of macro-scale hydrological models (MHMs) have been develop

  13. Summary appraisals of the Nation's ground-water resources; Hawaii region

    Science.gov (United States)

    Takasaki, K.J.

    1978-01-01

    The water resources of the Hawaii Region, taken as a whole, are far greater than foreseeable future demands on them, but this is not so for the individual islands. Each and every island is independent with respect to water supply, and the occurrence and availability of water vary widely from island to island.

  14. Geohydrology, simulation of ground-water flow, and ground-water quality at two landfills, Marion County, Indiana. Water Resources Investigation

    Energy Technology Data Exchange (ETDEWEB)

    Duwelius, R.F.; Greeman, T.K.

    1989-01-01

    The report presents the results of a study to provide a quantitative evaluation of the ground-water flow system at the Julietta and Tibbs-Banta landfills and provide a general description of the ground-water quality beneath and near the two landfills. These objectives provide the information necessary to evaluate the effects of the landfills on ground-water quality. Geologic, hydrologic, and water-quality data were collected in 1985 and 1986 at the Julietta and Tibbs-Banta landfills to fulfill the study objectives. Ground-water models were used to investigate the flow systems and estimate the volume of flow at the landfills. The report includes descriptions of the data collection, geologic and hydrologic descriptions of the two landfills, and brief histories of trash and sludge disposal. Ground-water-flow models are described and estimates of the volume of flow are discussed. A description of the quality-assurance plan used in conjunction with the water-quality data collection and analysis is included. Water-quality data are presented with statistical summaries of ground-water quality related to well depth and position in the flow system.

  15. Summary appraisals of the Nation's ground-water resources; Texas-Gulf region

    Science.gov (United States)

    Baker, E.T.; Wall, J.R.

    1976-01-01

    Ground water in the Texas-Gulf Region is a large and important resource that can provide a more significant percentage of the total water supply of the region. Total water requirements within the region are projected to rise sharply from 14 million acre-feet (17 cubic kilometres) in 1970 to nearly 26 million acre-feet (32 cubic kilometres) in 2020. About half of the water used in 1970 was ground water.

  16. Summary appraisals of the Nation's ground-water resources; Texas Gulf region

    Science.gov (United States)

    Baker, E.T.; Wall, James Ray

    1974-01-01

    Ground water in the Texas-Gulf Region is a large and important resource that can provide a more significant percentage of the total water supply of the region. Total water requirements within the region are projected to rise sharply from 14 million acre-feet (17 cubic kilometres) in 1970 to nearly 26 million acre-feet (32.cubic kilometres) in 2020. About half of the water used in 1970 was ground water.

  17. 3D geological modeling of the Kasserine Aquifer System, Central Tunisia: New insights into aquifer-geometry and interconnections for a better assessment of groundwater resources

    Science.gov (United States)

    Hassen, Imen; Gibson, Helen; Hamzaoui-Azaza, Fadoua; Negro, François; Rachid, Khanfir; Bouhlila, Rachida

    2016-08-01

    The challenge of this study was to create a 3D geological and structural model of the Kasserine Aquifer System (KAS) in central Tunisia and its natural extension into north-east Algeria. This was achieved using an implicit 3D method, which honors prior geological data for both formation boundaries and faults. A current model is presented which provides defendable predictions for the spatial distribution of geology and water resources in aquifers throughout the model-domain. This work has allowed validation of regional scale geology and fault networks in the KAS, and has facilitated the first-ever estimations of groundwater resources in this region by a 3D method. The model enables a preliminary assessment of the hydraulic significance of the major faults by evaluating their influence and role on groundwater flow within and between four compartments of the multi-layered, KAS hydrogeological system. Thus a representative hydrogeological model of the study area is constructed. The possible dual nature of faults in the KAS is discussed in the context that some faults appear to be acting both as barriers to horizontal groundwater flow, and simultaneously as conduits for vertical flow. Also discussed is the possibility that two flow directions occur within the KAS, at a small syncline area of near Feriana. In summary, this work evaluates the influence of aquifer connectivity and the role of faults and geology in groundwater flow within the KAS aquifer system. The current KAS geological model can now be used to guide groundwater managers on the best placement for drilling to test and further refine the understanding of the groundwater system, including the faults connectivity. As more geological data become available, the current model can be easily edited and re-computed to provide an updated model ready for the next stage of investigation by numerical flow modeling.

  18. Large-scale water resources management within the framework of GLOWA-Danube. Part A: The groundwater model

    Science.gov (United States)

    Barthel, Roland; Rojanschi, Vlad; Wolf, Jens; Braun, Juergen

    ), Software-Release No.: 0.9.2, Documentation Version: 0.10, Release Date: 27 March 2003] are required to solve the emerging problems. After a first successful public demonstration of the DANUBIA package (nine models) in May 2002 [Mauser, W., Stolz, R., Colgan, A., 2002. GLOWA-Danube: integrative techniques, scenarios and strategies regarding global change of the water cycle. In: GSF (Ed.), GLOWA, German Program on Global Change in the Hydrological Cycle (Phase I, 2000-2003) Status Report 2002. GSF, Munich, pp. 31-34], the research consortium is now preparing a first validation run of DANUBIA for the period 1995-1999 with all 15 models. After successful completion of the validation, a scenario run based on IPCC climate scenarios [IPCC, 2001. Climate Change 2001: Synthesis Report. In: Watson, R.T., Core Writing Team (Eds.), A Contribution of Working Groups I, II, and III to the Third Assessment Report of the Intergovernmental Panel on Climate Change. Cambridge University Press, Cambridge, UK and New York, NY, USA, 398pp] for a five year period between 2025 and 2040 will follow at the end of 2003. The research group “Groundwater and Water Resources Management” at the Institute of Hydraulic Engineering, Universität Stuttgart, is contributing both a three-dimensional groundwater flow model of the catchment and an agent-based model for simulating water supply and distribution. This paper gives a general overview of the GLOWA-Danube project and describes the groundwater modeling segment. Nickel et al. deal with the water supply model in a second contribution to this special issue. A three-dimensional numerical groundwater flow model consisting of four main layers has been developed and is in a continual state of refinement (MODFLOW, [McDonald, M.G., Harbaugh, A.W., 1988. A modular three-dimensional finite-difference ground-water flow model: US Geological Survey Techniques of Water-Resources Investigations, Washington, USA (book 6, Chapter A1)]). One main research focus has

  19. Trends in groundwater quality in relation to groundwater age

    NARCIS (Netherlands)

    Visser, A.

    2009-01-01

    Groundwater is a valuable natural resource and as such should be protected from chemical pollution. Because of the long travel times of pollutants through groundwater bodies, early detection of groundwater quality deterioration is necessary to efficiently protect groundwater bodies. The aim of this

  20. Trends in groundwater quality in relation to groundwater age

    NARCIS (Netherlands)

    Visser, A.

    2009-01-01

    Groundwater is a valuable natural resource and as such should be protected from chemical pollution. Because of the long travel times of pollutants through groundwater bodies, early detection of groundwater quality deterioration is necessary to efficiently protect groundwater bodies. The aim of this

  1. Transboundary study of the Milk River aquifer (Canada, USA): geological, conceptual and numerical models for the sound management of the regional groundwater resources

    Science.gov (United States)

    Pétré, Marie-Amélie; Rivera, Alfonso; Lefebvre, René

    2016-04-01

    The Milk River transboundary aquifer straddles southern Alberta (Canada) and northern Montana (United States), a semi-arid and water-short region. The extensive use of this regional sandstone aquifer over the 20th century has led to a major drop in water levels locally, and concerns about the durability of the resources have been raised since the mid-1950. Even though the Milk River Aquifer (MRA) has been studied for decades, most of the previous studies were limited by the international border, preventing a sound understanding of the aquifer dynamics. Yet, a complete portrait of the aquifer is required for proper management of this shared resource. The transboundary study of the MRA aims to overcome transboundary limitations by providing a comprehensive characterization of the groundwater resource at the aquifer scale, following a three-stage approach: 1) The development of a 3D unified geological model of the MRA (50,000 km2). The stratigraphic framework on both sides of the border was harmonized and various sources of geological data were unified to build the transboundary geological model. The delineation of the aquifer and the geometry and thicknesses of the geological units were defined continuously across the border. 2) Elaboration of a conceptual hydrogeological model by linking hydrogeological and geochemical data with the 3D unified geological model. This stage is based on a thorough literature review and focused complementary field work on both sides of the border. The conceptual model includes the determination of the groundwater flow pattern, the spatial distribution of hydraulic properties, a groundwater budget and the definition of the groundwater types. Isotopes (3H, 14C, 36Cl) were used to delineate the recharge area as well as the active and low-flow areas. 3) The building of a 3D numerical groundwater flow model of the MRA (26,000 km2). This model is a transposition of the geological and hydrogeological conceptual models. A pre

  2. Ground-water resources of the Yucca Valley-Joshua Tree area, San Bernardino County, California

    Science.gov (United States)

    Lewis, R.E.

    1972-01-01

    The southeastern part of the Mojave Water Agency area included in this report comprises about 600 square miles. Recharge into the area is almost exclusively from precipitation in the San Bernardino and Little San Bernardino Mountains. About 500 acre-feet per year of recharge enters the western part of the area as underflow through Pipes Wash. Little direct recharge occurs as a result of precipitation directly on the unconsolidated deposits. Presently about 11,000 persons reside in the area and current gross pumpage is about 1,600 acre-feet annually. By the year 2000 the population is estimated to be 62,000 and annual gross pumpage is expected to be nearly 11,000 acre-feet. Although over 1,200,000 acre-feet of ground water are presently in storage, most of the population is centered in the southern part of the area around the towns of Yucca Valley and Joshua Tree. About 70 percent of the population resides in the vicinity of Yucca Valley and is supplied by ground water pumped from the Warren Valley basin. Of the 96,000 acre-feet of ground water in storage in that basin in 1969, about 80,000 acre-feet will be necessary to sustain projected growth there until 2000. Assuming negligible recharge and only about 50 percent recovery of the ground water in storage, if imported water from northern California is not available before about 1990, additional local supplies will have to be developed, possibly in the adjacent Pipes subbasin to the north. Ground water in the southern part of the study area generally contains less than 250 mg/l (milligrams per liter) dissolved solids and 1.0 mg/l fluoride. A general degradation of ground-water quality occurs northward toward the dry lakes where the concentrations of dissolved solids and fluoride approach 2,000 and 5.0 mg/l, respectively. In Reche subbasin some isolated occurrences of fluoride exceeding 1.5 mg/l were noted. The chemical character of ground water in Johnson Valley and Morongo Valley basins differs from well to well

  3. The Observed Relationship between Management Styles and Resource Adequacy.

    Science.gov (United States)

    Lynch, David M.; And Others

    This descriptive study surveyed deans (N=142), department chairs (N=392), and faculty (N=1173) to examine their perceptions of the relationship between resource adequacy within institutions of higher education and administrators' management styles. The clusters of variables examined were: (1) management style (use of communication and…

  4. Hydrogeology and ground-water resources of Ngatik Island, Sapwuahfik Atoll, State of Pohnpei, Federated States of Micronesia

    Science.gov (United States)

    Anthony, S.S.

    1996-01-01

    The lens of fresh ground water on Ngatik Island contains about 509 million gallons of potable water. Recharge to the freshwater lens is estimated to be 990,000 gallons per day on the basis of an estimated mean annual rainfall of 160 inches. The long-term average sustainable yield is estimated to be about 280,000 gallons per day. The estimated demand for water is about 30,000 gallons per day. Shallow-vertical-tube-wells or horizontal-infiltration wells could be used to develop the freshwater lens. The effect of development on the lens can be determined by monitoring the chloride concentration of water from a network of shallow-water-table wells and deep driven wells. The ground-water resource on Ngatik can be used in conjunction with individual rainwater-catchment systems: rainwater can be used for drinking and cooking and ground water can be used for sanitary purposes. When rainwater- catchment systems fail during extended dry periods, ground water would be available to meet the total demand.

  5. Hydrogeology and ground-water resources of Pingelap Island, Pingelap Atoll, State of Pohnpei, Federated States of Micronesia

    Science.gov (United States)

    Anthony, S.S.

    1996-01-01

    The lens of fresh ground water on Pingelap Island, Pingelap Atoll contains about 384 million gallons of potable water. Recharge to the freshwater lens is estimated to be 230,000 gallons per day on the basis of an average annual rainfall of 160 inches. The long-term average sustainable yield is estimated to be about 69,000 gallons per day. The estimated demand for water is about 50,000 gallons per day. Shallow-vertical-tube wells or horizontal-infiltration wells could be used to develop the freshwater lens. The effect of development on the lens can be determined by monitoring the chloride concentration of water from a network of shallow-water-table wells and deep driven wells. The ground-water resource on Pingelap can be used in conjunction with individual rainwater-catchment systems: rainwater can be used for drinking and cooking, and ground water can be used for sanitary uses. When rainwater-catchment systems fail during extended dry periods, ground water would be available to meet the total demand.

  6. Global sampling to assess the value of diverse observations in conditioning a real-world groundwater flow and transport model

    Science.gov (United States)

    Delsman, Joost R.; Winters, Pieter; Vandenbohede, Alexander; Oude Essink, Gualbert H. P.; Lebbe, Luc

    2016-03-01

    The use of additional types of observational data has often been suggested to alleviate the ill-posedness inherent to parameter estimation of groundwater models and constrain model uncertainty. Disinformation in observational data caused by errors in either the observations or the chosen model structure may, however, confound the value of adding observational data in model conditioning. This paper uses the global generalized likelihood uncertainty estimation methodology to investigate the value of different observational data types (heads, fluxes, salinity, and temperature) in conditioning a groundwater flow and transport model of an extensively monitored field site in the Netherlands. We compared model conditioning using the real observations to a synthetic model experiment, to demonstrate the possible influence of disinformation in observational data in model conditioning. Results showed that the value of different conditioning targets was less evident when conditioning to real measurements than in a measurement error-only synthetic model experiment. While in the synthetic experiment, all conditioning targets clearly improved model outcomes, minor improvements or even worsening of model outcomes was observed for the real measurements. This result was caused by errors in both the model structure and the observations, resulting in disinformation in the observational data. The observed impact of disinformation in the observational data reiterates the necessity of thorough data validation and the need for accounting for both model structural and observational errors in model conditioning. It further suggests caution when translating results of synthetic modeling examples to real-world applications. Still, applying diverse conditioning data types was found to be essential to constrain uncertainty, especially in the transport of solutes in the model.

  7. Isotope hydrology applied to evaluation of groundwater in arid areas. Development of instruments for evaluating endangered groundwater resources. Isotopenhydrologische Methoden zur Begutachtung von Grundwasser in Trockengebieten. Entwicklung eines Instrumentariums fuer die Beurteilung gefaehrdeter Vorkommmen

    Energy Technology Data Exchange (ETDEWEB)

    Froehlich, K.; Geyh, M.A.; Verhagen, B.T.; Wirth, K.

    1987-01-01

    Capture of underground water in arid or semi-arid areas in developing countries is essential to safeguarding life. In order to realize in time, or to prevent, endangerment of exploitable groundwater resources due to pollution or excess exploitation, isotope hydrology offers low-cost methods that are applied along with other methods. Their results contribute to determine the origin, mixing, residence time (or age), and pollution of endangered groundwater resources. The research report in hand uses the results of hydrochemical analyses and isotope hydrological data from hydrogeological studies made over some years by the Bundesanstalt fuer Geowissenschaften und Rohstoffe in six selected countries: Jordan, Cyprus, Brazil, Sudan, Djibouti, Senegal. It also uses data of recent analyses of the years 1985 and 1986. Data evaluation is done applying modern, qualitative and quantitative methods of interpretation. The available long-term series of isotopic data are scanned for any early information on water quality deterioration that is not otherwise detected. The information thus obtained is a prerequisite of urgently needed measures for protecting the groundwater reserves.

  8. Groundwater Flow and Salt Transport at a Sand Tailings Dam: Field Observations and Modelling Results.

    Science.gov (United States)

    Price, A. C.; Mendoza, C. A.

    2004-05-01

    Large volumes of sand tailings are produced during the extraction of bitumen from the oil sands of Northeastern Alberta. The long-term groundwater response and subsequent movement of water and solutes within the large permeable sand tailings storage areas is uncertain. At the Southwest Sand Storage (SWSS) Facility, located at Syncrude's Mildred Lake operations near Ft. McMurray, there is concern that salts from the tailings water may discharge to newly placed reclamation material that covers the sand tailings. This saline discharge water could destroy the reclamation soil structure and negatively impact vegetation. The steady-state groundwater flow and transient movement of salts at the local (bench and slope) and intermediate (pile) scales in the SWSS are investigated. Water levels, seepage and groundwater quality (including TDS) have been measured for over a year along two transects of piezometers installed in the SWSS. The field data have been used to complete traditional hydrogeological interpretations of the site, and to develop a conceptual model of flow and transport. The local and intermediate flow systems and salt transport in the dam are being evaluated with numerical models. The models will allow possible future hydrogeological behaviour of the structure to be tested. Preliminary results show differences in flow systems and salinity distribution that depend on the deposition of the SWSS. This research will facilitate better long-term environmental management of this and similar sites.

  9. Assessing the recharge of a coastal aquifer using physical observations, tritium, groundwater chemistry and modelling.

    Science.gov (United States)

    Santos, Isaac R; Zhang, Chenming; Maher, Damien T; Atkins, Marnie L; Holland, Rodney; Morgenstern, Uwe; Li, Ling

    2017-02-15

    Assessing recharge is critical to understanding groundwater and preventing pollution. Here, we investigate recharge in an Australian coastal aquifer using a combination of physical, modelling and geochemical techniques. We assess whether recharge may occur through a pervasive layer of floodplain muds that was initially hypothesized to be impermeable. At least 59% of the precipitation volume could be accounted for in the shallow aquifer using the water table fluctuation method during four significant recharge events. Precipitation events 14% of annual precipitation). Tritium dating revealed long term net vertical recharge rates ranging from 27 to 114mm/year (average 58mm/year) which were interpreted as minimum net long term recharge. Borehole experiments revealed more permeable conditions and heterogeneous infiltration rates when the floodplain soils were dry. Wet conditions apparently expand floodplain clays, closing macropores and cracks that act as conduits for groundwater recharge. Modelled groundwater flow paths were consistent with tritium dating and provided independent evidence that the clay layer does not prevent local recharge. Overall, all lines of evidence demonstrated that the coastal floodplain muds do not prevent the infiltration of rainwater into the underlying sand aquifer, and that local recharge across the muds was widespread. Therefore, assuming fine-grained floodplain soils prevent recharge and protect underlying aquifers from pollution may not be reasonable. Copyright © 2016 Elsevier B.V. All rights reserved.

  10. QUALITATIVE CHARACTERIZATION OF GROUNDWATER RESOURCES FOR IRRIGATION- A CASE STUDY FROM SRIKAKULAM AREA, ANDHRA PRADESH, INDIA.

    Directory of Open Access Journals (Sweden)

    Dr.K.S.S.N.Reddy ,

    2011-06-01

    Full Text Available The rapid growth in the population caused unprecedented increase in demand of water resources. Besides, an improved quality of life is often associated with higher water demands. The suitability of a particular water for irrigation use depends on many factors; chemical quality of water being an important one. Quality criteria for irrigation use are based on the tolerance of plants, properties of soils, climate and irrigation practices, Water consumed by plants should be free from dissolved material. Plants normally retain some nutrients and mineral matter originally dissolved in water, and the cations and anions, so retained is a small part of their total content. The mineral matter retained by plants consists mostly of calcium and magnesium salts (Easton, 1954. Other soluble matter remains behind in the soil. Calcium carbonate may precipitate harmlessly in the soil as solute concentrations increases, but the bulk of the residual solute creates disposable problems that must be solved effectively to maintain the fertility of the irrigated soil. The most pertinent chemical properties patient to the evaluation of solubility of water for agricultural use are as Sodium concentration, an index showing the sodium or alkali hazards., Total concentration of soluble salts, an index showing salinity hazard, Residual SodiumCarbonate concentration. Hence, a scientific study, which includes various integrated methodologies and evaluation of alluvial aquifers, has been proposed in Nagavali and Vamsadhara river basin, in Srikakulam district, Andhra Pradesh, Indian.

  11. Ground-water resources of the Lambayeque Valley, Department of Lambayeque, northern Peru

    Science.gov (United States)

    Schoff, Stuart L.; Sayan, M. Juan Luis

    1969-01-01

    possibly water bearing. Water in the alluvium of the eastern part of the area occurs under water-table conditions at depths from 1 to 8 m below the land surface. The water table declines during pumping for irrigation and rises when pumping is stopped. Recharge comes mainly from infiltration on irrigated fields and from irrigation ditches and probably varies greatly from year to year at any given place. The ground-water reservoir is replenished when pumps are idle; therefore, it is concluded that the recharge is sufficient to offset withdrawal at a rate comparable to that of 1957, which was about 81 million cum (cubic meters). A study of the effect of protracted pumping on yields of wells suggests that the rate of recharge locally, and for a short period, was more than 76,000 cu m per day. This recharge presumably declined rapidly to zero when irrigation was suspended in the locality. A pumping test showed the transmissivity to be about 950 cu m per day per m and the storage coefficient to be about 0.07. Based on these coefficients, the drawdown caused by one well discharging 10 lps (liters per second) for 6 months would be only 0.066 m at points 4,000 m distant, but 50 wells at the same rate and distance would create 3.3 m of drawdown. As actual distances between wells range from 100 to 300 m where the wells are most numerous and as the average discharge rate is nearer to 20 than to 10 lps, the cumulative effect of the actual pumping is certain to be considerable. If it were not for the recharge resulting from infiltration of irrigation water, the pumping of so many wells probably could not be long sustained. The waters from wells of the Lambayeque Valley compare favorably, in most respects, with the standards established by the U.S. Public Health Service for water for human consumption. Chemical analyses of 10 samples of ground water show that the dissolved solids, silica, bicarbonate, sulfate, and sodium increase in the downstream direction, where

  12. Geology and ground-water resources of the Deer Lodge Valley, Montana

    Science.gov (United States)

    Konizeski, Richard L.; McMurtrey, R.G.; Brietkrietz, Alex

    1968-01-01

    clay to boulder-sized aggregates. Throughout most of the area the strata dip gently towards the valley axis, but along the western margins of the valley they dip steeply into the mountains. In late Pliocene or early Pleistocene the Tertiary strata were eroded to a nearly regular valley divide surface. In the western part of the valley the erosion surface was thinly mantled by glacial debris from the Flint Creek Range. Still later, probably during several interglacial intervals, the Clark Fork and its tributaries entrenched themselves in the Tertiary strata to an average depth of about 150 feet. The resultant erosional features were further modified by Wisconsin to Recent glaciofluvial deposition. Three east-west cross .sections and a corrected gravity map were drawn for the valley. They indicate a maximum depth of fill of more than 5,500 feet in the southern part. Depths decrease to the north to approximately 2,300 feet near the town of Deer Lodge. The principal source of ground water in the Deer Lodge Valley is the upper few hundred feet of unconsolidated valley fill. Most of the wells tapping these deposits range in depth from a few feet to 250 feet. Water levels range from somewhat above land surface (in flowing wells) to about 150 feet below. Yields of the wells range from a few gallons per minute to 1,000 gallons per minute. Generally, wells having the highest yields are on the flood plain of the Clark Fork or the coalescent fans of Warm Springs and Mill Creeks. Discharge of ground water by seepage into streams, by evapotranspiration, and by pumping from wells causes a gradual lowering of the water table. Each spring and early summer, seepage of water from irrigation and streams and infiltration of water from snowmelt and precipitation replenish the ground-water reservoir. Seasonal fluctuation of the water table generally is less than 10 feet. The small yearly water table fluctuation indicates that recharge about balances discharge from th

  13. Geology and ground-water resources of Washington, D.C., and vicinity

    Science.gov (United States)

    Johnston, Paul McKelvey

    1964-01-01

    constructed. Bored or dug wells allow greater storage capacity and are satisfactory for domestic supplies in some locations, but they are polluted easily. If not properly constructed or of sufficient depth, they may fail in dry weather. Ground-water supplies for domestic use, 5 to 10 gpm (gallons per minute), are obtainable in most places. In the Piedmont, recorded yields in drilled wells range from 0.2 to 212 gpm. In the Coastal Plain, wells yield from 1 to 800 gpm. The quality of the ground water in the report area is generally satisfactory for domestic, industrial, and irrigation use. High iron content and corrosiveness are troublesome in places. The water is soft to moderately hard--2 to 175 ppm (parts per million). Water in the Piedmont province is. dominantly the calcium and bicarbonate type; in the Coastal Plain most water is of calcium-magnesium bicarbonate type. In the Piedmont, careful location of wells with respect to the geology (rock type and structure) and to topography usually results in higher yields and may mean the difference between success and failure. In the Coastal Plain, drilled artesian wells are not affected by topography, but the yield obtained depends upon the penetration of a water-bearing sand or gravel bed at sufficient depth. The early settlers obtained water from the springs and streams, and later from dug wells. After Washington was established as the Capital in 1800, water was obtained from public and privately owned wells. Water was piped from some of the springs to government buildings and to private homes and business houses. In 1863 a diversion dam was completed in the Potomac above Great Falls and a conduit was built into the city to furnish a public water supply. This system with modifications has been in use ever since. A new diversion dam and pumping station at Little Falls was put into service in the summer of 1959. In 1961 the total pumpage from Coastal Plain aquifers in the report area was estimate

  14. Thermal infrared remote sensing in assessing groundwater and surface-water resources related to Hannukainen mining development site, northern Finland

    Science.gov (United States)

    Rautio, Anne B.; Korkka-Niemi, Kirsti I.; Salonen, Veli-Pekka

    2017-07-01

    Mining development sites occasionally host complicated aquifer systems with notable connections to natural surface water (SW) bodies. A low-altitude thermal infrared (TIR) imaging survey was conducted to identify hydraulic connections between aquifers and rivers and to map spatial surface temperature patterns along the subarctic rivers in the proximity of the Hannukainen mining development area, northern Finland. In addition to TIR data, stable isotopic compositions (δ 18O, δD) and dissolved silica concentrations were used as tracers to verify the observed groundwater (GW) discharge into the river system. Based on the TIR survey, notable GW discharge into the main river channel and its tributaries (61 km altogether) was observed and over 500 GW discharge sites were located. On the basis of the survey, the longitudinal temperature patterns of the studied rivers were found to be highly variable. Hydrological and hydrogeological information is crucial in planning and siting essential mining operations, such as tailing areas, in order to prevent any undesirable environmental impacts. The observed notable GW discharge was taken into consideration in the planning of the Hannukainen mining development area. The results of this study support the use of TIR imagery in GW-SW interaction and environmental studies in extensive and remote areas with special concerns for water-related issues but lacking the baseline research.

  15. 海河流域地下水资源保护%Groundwater resources protection in Hai River basin of China

    Institute of Scientific and Technical Information of China (English)

    韩再生

    2001-01-01

    The groundwater resources in Hai River basin of China represent a vital water resource.Both the shallow and deep aquifers are highly over-exploited in a large area of Hai river basin.The heavy over-exploitation of the groundwater resources in causing huge environmental damae.For protecting groundwater resource,technical feasibility was evaluated.Artificial recharge using floodwater and wastewater has been tried and performed.Surface spreading systems are applicable in many areas.Deep aquifer injection is undertaken in the urban area.A much better strategy is to reduce the extraction of groundwater,especially for stopping or slowing down land subsidence and seawater intrusion.To solve the problem of falling groundwater levels and aquifer recovery,it is necessary to incorporate both a reduction in groundwater extraction and artificial recharge.%地下水资源在海河流域为至关重要的资源。海河平原的的浅层和深层含水层大面积处于严重超采状态。地下水资源的过量开采造成了严重环境问题。为了保护地下水资源,评价了可行的技术。利用洪水和废水进行人工回灌已进行了试验。在很多地区可以应用地表回灌系统,城市地区实施深层含水层的回灌。更好的策略是减少地下水的抽取量,特别是为了减缓地面沉降和海水入侵。应该联合运用减少地下水抽水量和人工回灌,以解决地下水位持续下降和含水层恢复的问题。

  16. Simulated effects of groundwater pumping and artificial recharge on surface-water resources and riparian vegetation in the Verde Valley sub-basin, Central Arizona

    Science.gov (United States)

    Leake, Stanley A.; Pool, Donald R.

    2010-01-01

    In the Verde Valley sub-basin, groundwater use has increased in recent decades. Residents and stakeholders in the area have established several groups to help in planning for sustainability of water and other resources of the area. One of the issues of concern is the effect of groundwater pumping in the sub-basin on surface water and on groundwater-dependent riparian vegetation. The Northern Arizona Regional Groundwater-Flow Model by Pool and others (in press) is the most comprehensive and up-to-date tool available to understand the effects of groundwater pumping in the sub-basin. Using a procedure by Leake and others (2008), this model was modified and used to calculate effects of groundwater pumping on surface-water flow and evapotranspiration for areas in the sub-basin. This report presents results for the upper two model layers for pumping durations of 10 and 50 years. Results are in the form of maps that indicate the fraction of the well pumping rate that can be accounted for as the combined effect of reduced surface-water flow and evapotranspiration. In general, the highest and most rapid responses to pumping were computed to occur near surface-water features simulated in the modified model, but results are not uniform along these features. The results are intended to indicate general patterns of model-computed response over large areas. For site-specific projects, improved results may require detailed studies of the local hydrologic conditions and a refinement of the modified model in the area of interest.

  17. Ground-Water Resources in Kaloko-Honokohau National Historical Park, Island of Hawaii, and Numerical Simulation of the Effects of Ground-Water Withdrawals

    Science.gov (United States)

    Oki, Delwyn S.; Tribble, Gordon W.; Souza, William R.; Bolke, Edward L.

    1999-01-01

    Within the Kaloko-Honokohau National Historical Park, which was established in 1978, the ground-water flow system is composed of brackish water overlying saltwater. Ground-water levels measured in the Park range from about 1 to 2 feet above mean sea level, and fluctuate daily by about 0.5 to 1.5 feet in response to ocean tides. The brackish water is formed by mixing of seaward flowing fresh ground water with underlying saltwater from the ocean. The major source of fresh ground water is from subsurface flow originating from inland areas to the east of the Park. Ground-water recharge from the direct infiltration of precipitation within the Park area, which has land-surface altitudes less than 100 feet, is small because of low rainfall and high rates of evaporation. Brackish water flowing through the Park ultimately discharges to the fishponds in the Park or to the ocean. The ground water, fishponds, and anchialine ponds in the Park are hydrologically connected; thus, the water levels in the ponds mark the local position of the water table. Within the Park, ground water near the water table is brackish; measured chloride concentrations of water samples from three exploratory wells in the Park range from 2,610 to 5,910 milligrams per liter. Chromium and copper were detected in water samples from the three wells in the Park and one well upgradient of the Park at concentrations of 1 to 5 micrograms per liter. One semi-volatile organic compound, phenol, was detected in water samples from the three wells in the Park at concentrations between 4 and 10 micrograms per liter. A regional, two-dimensional (areal), freshwater-saltwater, sharp-interface ground-water flow model was used to simulate the effects of regional withdrawals on ground-water flow within the Park. For average 1978 withdrawal rates, the estimated rate of fresh ground-water discharge to the ocean within the Park is about 6.48 million gallons per day, or about 3 million gallons per day per mile of coastline

  18. Continuous and event-based time series analysis of observed floodplain groundwater flow under contrasting land-use types.

    Science.gov (United States)

    Kellner, Elliott; Hubbart, Jason A

    2016-10-01

    There is an ongoing need to improve quantitative understanding of land-use impacts on floodplain groundwater flow regimes. A study was implemented in Hinkson Creek Watershed, Missouri, USA, including equidistant grids of nine piezometers, equipped with pressure transducers, which were installed at two floodplain study sites: a remnant bottomland hardwood forest (BHF) and a historical agricultural field (Ag). Data were logged at thirty minute intervals for the duration of the 2011, 2012, 2013, and 2014 water years (October 1, 2010-September 30, 2014). Results show significant (pflood attenuation capacity and streamwater buffering potential by the BHF floodplain, relative to the Ag, and highlight the value of floodplain forests as a land and water resource management tool.

  19. Earth Resources Observation and Science (EROS) Center's Earth as Art Image Gallery

    Data.gov (United States)

    National Aeronautics and Space Administration — The Earth Resources Observation and Science (EROS) Center manages this collection of Landsat 7 scenes created for aesthetic purposes rather than scientific...

  20. Groundwater and surface-water resources in the Bureau of Land Management Moab Master Leasing Plan area and adjacent areas, Grand and San Juan Counties, Utah, and Mesa and Montrose Counties, Colorado

    Science.gov (United States)

    Masbruch, Melissa D.; Shope, Christopher L.

    2014-01-01

    The Bureau of Land Management (BLM) Canyon Country District Office is preparing a leasing plan known as the Moab Master Leasing Plan (Moab MLP) for oil, gas, and potash mineral rights in an area encompassing 946,469 acres in southeastern Utah. The BLM has identified water resources as being potentially affected by oil, gas, and potash development and has requested that the U.S. Geological Survey prepare a summary of existing water-resources information for the Moab MLP area. This report includes a summary and synthesis of previous and ongoing investigations conducted in the Moab MLP and adjacent areas in Utah and Colorado from the early 1930s through the late 2000s.Eight principal aquifers and six confining units were identified within the study area. Permeability is a function of both the primary permeability from interstitial pore connectivity and secondary permeability created by karst features or faults and fractures. Vertical hydraulic connection generally is restricted to strongly folded and fractured zones, which are concentrated along steeply dipping monoclines and in narrow regions encompassing igneous and salt intrusive masses. Several studies have identified both an upper and lower aquifer system separated by the Pennsylvanian age Paradox Member of the Hermosa Formation evaporite, which is considered a confining unit and is present throughout large parts of the study area.Surface-water resources of the study area are dominated by the Colorado River. Several perennial and ephemeral or intermittent tributaries join the Colorado River as it flows from northeast to southwest across the study area. An annual spring snowmelt and runoff event dominates the hydrology of streams draining mountainous parts of the study area, and most perennial streams in the study area are snowmelt-dominated. A bimodal distribution is observed in hydrographs from some sites with a late-spring snowmelt-runoff peak followed by smaller peaks of shorter duration during the late summer

  1. Food supply reliance on groundwater

    Science.gov (United States)

    Dalin, Carole; Puma, Michael; Wada, Yoshihide; Kastner, Thomas

    2016-04-01

    Water resources, essential to sustain human life, livelihoods and ecosystems, are under increasing pressure from population growth, socio-economic development and global climate change. As the largest freshwater resource on Earth, groundwater is key for human development and food security. Yet, excessive abstraction of groundwater for irrigation, driven by an increasing demand for food in recent decades, is leading to fast exhaustion of groundwater reserves in major agricultural areas of the world. Some of the highest depletion rates are observed in Pakistan, India, California Central Valley and the North China Plain aquifers. In addition, the growing economy and population of several countries, such as India and China, makes prospects of future available water and food worrisome. In this context, it is becoming particularly challenging to sustainably feed the world population, without exhausting our water resources. Besides, food production and consumption across the globe have become increasingly interconnected, with many areas' agricultural production destined to remote consumers. In this globalisation era, trade is crucial to the world's food system. As a transfer of water-intensive goods, across regions with varying levels of water productivity, food trade can save significant volumes of water resources globally. This situation makes it essential to address the issue of groundwater overuse for global food supply, accounting for international food trade. To do so, we quantify the current, global use of non-renewable groundwater for major crops, accounting for various water productivity and trade flows. This will highlight areas requiring quickest attention, exposing major exporters and importers of non-renewable groundwater, and thus help explore solutions to improve the sustainability of global food supply.

  2. Over Exploitation of Groundwater in the Centre of Amman Zarqa Basin—Jordan: Evaluation of Well Data and GRACE Satellite Observations

    Directory of Open Access Journals (Sweden)

    Sana’a Al-Zyoud

    2015-11-01

    Full Text Available Jordan faces a sincere water crisis. Groundwater is the major water resource in Jordan and most of the ground water systems are already exploited beyond their estimated safe yield. The Amman Zarqa Basin is one of the most important groundwater systems in Jordan, which supplies the three largest cities in Jordan with drinking and irrigation water. Based on new data the groundwater drawdown in the Amman Zarqa Basin is studied. This basin is the most used drainage area in Jordan. Groundwater drawdown in eight central representative monitoring wells is outlined. Based on almost continuous data for the last 15 years (2000–2015 an average drawdown for the whole basin in the order of 1.1 m·a−1 is calculated. This result is in accordance with results of previous studies in other areas in Jordan and shows that, until now, no sustainable water management is applied. Groundwater management in such a basin presents a challenge for water managers and experts. The applicability of satellite data for estimating large-scale groundwater over exploitation, such as gravity products of the Gravity Recovery and Climate Experiment (GRACE mission, along with supplementary data, is discussed. Although the size of the basin is below the minimum resolution of GRACE, the data generally support the measured drawdown.

  3. Impact of climate change on renewable groundwater resources: assessing the benefits of avoided greenhouse gas emissions using selected CMIP5 climate projections

    Science.gov (United States)

    Portmann, Felix T.; Döll, Petra; Eisner, Stephanie; Flörke, Martina

    2013-06-01

    Reduction of greenhouse gas (GHG) emissions to minimize climate change requires very significant societal effort. To motivate this effort, it is important to clarify the benefits of avoided emissions. To this end, we analysed the impact of four emissions scenarios on future renewable groundwater resources, which range from 1600 GtCO2 during the 21st century (RCP2.6) to 7300 GtCO2 (RCP8.5). Climate modelling uncertainty was taken into account by applying the bias-corrected output of a small ensemble of five CMIP5 global climate models (GCM) as provided by the ISI-MIP effort to the global hydrological model WaterGAP. Despite significant climate model uncertainty, the benefits of avoided emissions with respect to renewable groundwater resources (i.e. groundwater recharge (GWR)) are obvious. The percentage of projected global population (SSP2 population scenario) suffering from a significant decrease of GWR of more than 10% by the 2080s as compared to 1971-2000 decreases from 38% (GCM range 27-50%) for RCP8.5 to 24% (11-39%) for RCP2.6. The population fraction that is spared from any significant GWR change would increase from 29% to 47% if emissions were restricted to RCP2.6. Increases of GWR are more likely to occur in areas with below average population density, while GWR decreases of more than 30% affect especially (semi)arid regions, across all GCMs. Considering change of renewable groundwater resources as a function of mean global temperature (GMT) rise, the land area that is affected by GWR decreases of more than 30% and 70% increases linearly with global warming from 0 to 3 ° C. For each degree of GMT rise, an additional 4% of the global land area (except Greenland and Antarctica) is affected by a GWR decrease of more than 30%, and an additional 1% is affected by a decrease of more than 70%.

  4. Global-scale assessment of groundwater depletion and related groundwater abstractions: Combining hydrological modeling with information from well observations and GRACE satellites

    Science.gov (United States)

    Döll, Petra; Müller Schmied, Hannes; Schuh, Carina; Portmann, Felix T.; Eicker, Annette

    2014-07-01

    Groundwater depletion (GWD) compromises crop production in major global agricultural areas and has negative ecological consequences. To derive GWD at the grid cell, country, and global levels, we applied a new version of the global hydrological model WaterGAP that simulates not only net groundwater abstractions and groundwater recharge from soils but also groundwater recharge from surface water bodies in dry regions. A large number of independent estimates of GWD as well as total water storage (TWS) trends determined from GRACE satellite data by three analysis centers were compared to model results. GWD and TWS trends are simulated best assuming that farmers in GWD areas irrigate at 70% of optimal water requirement. India, United States, Iran, Saudi Arabia, and China had the highest GWD rates in the first decade of the 21st century. On the Arabian Peninsula, in Libya, Egypt, Mali, Mozambique, and Mongolia, at least 30% of the abstracted groundwater was taken from nonrenewable groundwater during this time period. The rate of global GWD has likely more than doubled since the period 1960-2000. Estimated GWD of 113 km3/yr during 2000-2009, corresponding to a sea level rise of 0.31 mm/yr, is much smaller than most previous estimates. About 15% of the globally abstracted groundwater was taken from nonrenewable groundwater during this period. To monitor recent temporal dynamics of GWD and related water abstractions, GRACE data are best evaluated with a hydrological model that, like WaterGAP, simulates the impact of abstractions on water storage, but the low spatial resolution of GRACE remains a challenge.

  5. RCRA (Resource Conservation and Recovery Act of 1976) ground-water monitoring projects for Hanford facilities: Progress report, October 1--December 31, 1988: Volume 1, Text

    Energy Technology Data Exchange (ETDEWEB)

    Fruland, R.M.; Bates, D.J.; Lundgren, R.E.

    1989-04-01

    This report describes the progress of 13 Hanford ground-water monitoring projects for the period October 1 to December 31, 1988. There are 16 individual hazardous waste facilities covered by the 13 ground-water monitoring projects. The Grout Treatment Facility is included in this series of quarterly reports for the first time. The 13 projects discussed in this report were designed according to applicable interim-status ground-water monitoring requirements specified in the Resource Conservation and Recovery Act of 1976 (RCRA). During this quarter, field activities primarily consisted of sampling and analyses, and water-level monitoring. The 200 Areas Low-Level Burial Grounds section includes sediment analyses in addition to ground-water monitoring results. Twelve new wells were installed during the previous quarter: two at the 216-A-29 Ditch, six at the 216-A-10 Crib, and four at the 216-B-3 Pond. Preliminary characterization data for these new wells include drillers' logs and other drilling and site characterization data, and are provided in Volume 2 or on microfiche in the back of Volume 1. 26 refs., 28 figs., 74 tabs.

  6. Study on the Estimation of Groundwater Withdrawals Based on Groundwater Flow Modeling and Its Application in the North China Plain

    Institute of Scientific and Technical Information of China (English)

    Jingli Shao; Yali Cui; Qichen Hao; Zhong Han; Tangpei Cheng

    2014-01-01

    The amount of water withdrawn by wells is one of the quantitative variables that can be applied to estimate groundwater resources and further evaluate the human influence on ground-water systems. The accuracy for the calculation of the amount of water withdrawal significantly in-fluences the regional groundwater resource evaluation and management. However, the decentralized groundwater pumping, inefficient management, measurement errors and uncertainties have resulted in considerable errors in the groundwater withdrawal estimation. In this study, to improve the esti-mation of the groundwater withdrawal, an innovative approach was proposed using an inversion method based on a regional groundwater flow numerical model, and this method was then applied in the North China Plain. The principle of the method was matching the simulated water levels with the observation ones by adjusting the amount of groundwater withdrawal. In addition, uncertainty analysis of hydraulic conductivity and specific yield for the estimation of the groundwater with-drawal was conducted. By using the proposed inversion method, the estimated annual average groundwater withdrawal was approximately 24.92×109 m3 in the North China Plain from 2002 to 2008. The inversion method also significantly improved the simulation results for both hydrograph and the flow field. Results of the uncertainty analysis showed that the hydraulic conductivity was more sensitive to the inversion results than the specific yield.

  7. Uncertainty in global groundwater storage estimates in a Total Groundwater Stress framework

    Science.gov (United States)

    Richey, Alexandra S.; Thomas, Brian F.; Lo, Min‐Hui; Swenson, Sean; Rodell, Matthew

    2015-01-01

    Abstract Groundwater is a finite resource under continuous external pressures. Current unsustainable groundwater use threatens the resilience of aquifer systems and their ability to provide a long‐term water source. Groundwater storage is considered to be a factor of groundwater resilience, although the extent to which resilience can be maintained has yet to be explored in depth. In this study, we assess the limit of groundwater resilience in the world's largest groundwater systems with remote sensing observations. The Total Groundwater Stress (TGS) ratio, defined as the ratio of total storage to the groundwater depletion rate, is used to explore the timescales to depletion in the world's largest aquifer systems and associated groundwater buffer capacity. We find that the current state of knowledge of large‐scale groundwater storage has uncertainty ranges across orders of magnitude that severely limit the characterization of resilience in the study aquifers. Additionally, we show that groundwater availability, traditionally defined as recharge and redefined in this study as total storage, can alter the systems that are considered to be stressed versus unstressed. We find that remote sensing observations from NASA's Gravity Recovery and Climate Experiment can assist in providing such information at the scale of a whole aquifer. For example, we demonstrate that a groundwater depletion rate in the Northwest Sahara Aquifer System of 2.69 ± 0.8 km3/yr would result in the aquifer being depleted to 90% of its total storage in as few as 50 years given an initial storage estimate of 70 km3. PMID:26900184

  8. Pesticides in groundwater: modelling and data analysis of the past, present and future

    DEFF Research Database (Denmark)

    Binning, Philip John; McKnight, Ursula S.; Malaguerra, Flavio

    to jointly manage our groundwater and surface water resources. Here, observed pesticide data is analyzed and combined with models to address these questions and needs. Groundwater and surface water pesticide observations reflect the fact that these two hydrological components have a strong interaction...

  9. Observations of Active Submarine Groundwater Discharge on a Shallow Coastal Sea in Yucatan, Mexico

    Science.gov (United States)

    Marino, I.; Vera, I.; Enriquez, C.; Capurro, L.; Kantun, C.

    2008-12-01

    This contribution presents detailed measurements of fresh water fluxes from an energetic submarine groundwater discharge (SGD) located on the coastal ocean on Dzilam Bravo, Yucatan, Mexico. Due to the geologic characteristics of the site (karstic geology), inland groundwater flows through karstic conduits and exits at sea. Time series of fluxes measured by an acoustic velocimeter (VECTOR), temperature and salinity are correlated to the variability imposed by tides, currents, waves and rainfall. The contribution of SGD is a determining factor in the dynamics of marine ecosystems because it provides fresh water, nutrients, contaminants and other solutes. For this reason it is important to increase the knowledge about its dynamics and mixing processes that take place in these kind of environments. To study the spacial variability of thermohaline conditions, an area of 1 by 1 km (which includes five freshwater springs) was measured with a vessel towed CTD during drough and rainfall seasons. The results reveal that the flow conditions for the main spring (X'buya-Ha) is controlled by sea level variations, which include tides and weather effects. The outflow velocity is about 0.5 m/s during dry season when the discharge is weak, and about 3 m/s during periods of intense rainfall, when the discharge is strong. Also, it was noted that outflow direction changes as a result of high and low tides along a day. Results will be presented on the spatial influence as well, showing that the effect of the springs is very localised during high tide, but expands considerably during low tides.

  10. A new concept of irrigation response units for effective management of surface and groundwater resources: a case study from the multi-country Fergana Valley, Central Asia

    KAUST Repository

    Awan, Usman Khalid

    2016-09-09

    When estimating canal water supplies for large-scale irrigation schemes and especially in arid regions worldwide, the impact of all factors affecting the gross irrigation requirements (GIR) are not properly accounted for, which results in inefficient use of precious freshwater resources. This research shows that the concept of irrigation response units (IRU)—areas having unique combinations of factors effecting the GIR—allows for more precise estimates of GIR. An overlay analysis of soil texture and salinity, depth and salinity of groundwater, cropping patterns and irrigation methods was performed in a GIS environment, which yielded a total of 17 IRUs combinations of the Oktepa Zilol Chashmasi water consumers’ association in multi-country Fergana Valley, Central Asia. Groundwater contribution, leaching requirements, losses in the irrigation system through field application and conveyance and effective rainfall were included in GIR estimates. The GIR varied significantly among IRUs [average of 851 mm (±143 mm)] with a maximum (1051 mm) in IRU-12 and a minimum (629 mm) in IRUs-15, 16. Owing to varying groundwater levels in each IRU, the groundwater contribution played a key role in the estimation of the GIR. The maximum groundwater contribution occurred in IRUs dominated by cotton–fallow rotations as evidenced by an average value of 159 mm but a maximum of 254 mm and a minimum of 97 mm. Percolation losses depended on irrigation methods for different crops in their respective IRUs. The novel approach can guide water managers in this and similar regions to increase the accuracy of irrigation demands based on all the factor effecting the GIR. © 2016 Springer-Verlag Berlin Heidelberg

  11. Exploitation of Deep Groundwater Resource in Coastal Plain%滨海平原深层地下水资源开采研究

    Institute of Scientific and Technical Information of China (English)

    王开位; 唐正斌; 刘继朝

    2013-01-01

    In order to build deep groundwater resource in coastal plain,with a water resource exploration as an example,we adopt multiple approaches such as hydrogeological mapping,geophysical prospecting,hydrogeological drilling and pumping test to study hydrogeological characteristics and constraints.The results show that there are two deep groundwater mining sections in 300-700 m with mineralization degree of no more than 2 g/L,and inflow of water in each mining section is about 40 m3/h.Deep groundwater is far from supply area,and groundwater flow is slow; main groundwater discharge way is artificial exploitation,and natural groundwater flow direction has been changed,emergency well-field can only be built.1.7 × 104 m3/d well-field can be built in the general area in the range of 52 km2,and in l0 years environmental geological problems will not affect the normal operation of well-field.%为建立滨海平原深层地下水水源地,以某一水源地勘探为例,采用水文地质测绘、物探、钻探及抽水试验等多种手段勘查,研究滨海平原水文地质特征及水资源开发约束条件.结果表明,在地下300~ 700 m存在两个矿化度不大于2 g/L的深层地下水开采段,每个开采段涌水量约40 m3/h;深层地下水距补给区较远,地下水迳流缓慢,主要排泄方式为人工开采,受人工开采影响,天然地下水流向已被改变,适宜建立应急水源地;在概化面积52 km2的范围内建立1.7×104 m3/d的水源地,地面沉降、咸水运移及海水入侵问题在10年内不会影响水源地的正常运营.

  12. Transfer of European Approach to Groundwater Monitoring in China

    Science.gov (United States)

    Zhou, Y.

    2007-12-01

    in 3 pilot areas have been conducted to build research capacities of the central and provincial groundwater information centers in providing groundwater information services to decision makers and public. Groundwater regime zoning and pollution risk maps were used to lay-out groundwater quantity and quality monitoring networks, respectively. Automatic groundwater recorders were installed in selected observation wells. ArcGIS based regional groundwater information systems were constructed and used to create groundwater regime zoning and pollution risk maps. Steady state groundwater models have been constructed and calibrated. Transient groundwater models are under calibration. Groundwater resources development scenarios were formulated. The model will be used to predict what will be consequences in next 20 years if current situation continues as business as usual. Possibilities of reducing groundwater abstraction and opportunities of artificially enhanced groundwater recharge will be analyzed. Combination of decreasing abstraction and increasing recharge may lead to a sustainable plan of future groundwater resources development.

  13. Groundwater sustainability in Asian Mega city

    Science.gov (United States)

    Taniguchi, M.

    2009-12-01

    Population increased in many Asian coastal cities, and increased demand of groundwater as water resources caused many subsurface environments. Subsurface environmental problems such as land subsidence due to excessive pumping, groundwater contamination and subsurface thermal anomaly, have occurred repeatedly in Asian mega cities with a time lag depending on the development stage of urbanization. This study focus on four subjects; urban, water, heat, and material in subsurface environment, and intensive field observations and data collections had been made in the basins including Tokyo, Osaka, Bangkok, Jakarta, Manila, Seoul, and Taipei. The new methods for evaluating the changes in groundwater storage by gravimeter measurements in situ and Satellite GRACE, and residence time evaluation by 85Kr and CFCs, have been developed in this study. The combined effects of heat island and global warming from subsurface temperature in Asian mega cities evaluated the magnitude and timing of the urbanization which were preserved in subsurface thermal environment. The effects of law/institution on change in reliable water resources between groundwater and surface water, have been also investigated. The groundwater is “private water”, on the other hand, the surface water is “public water”. Regulation of groundwater pumping due to serious land subsidence did not work without alternative water resources, and the price of water is another major factor for the change in reliable water resources between groundwater and surface water. Land use/cover changes at three ages (1940’s, 1970’s and 2000’s) have been analyzed based on GIS with 0.5 km grid at seven targeted cities. The development of integrated indicators based on GIS for understanding the relationship between human activities and subsurface environment have been made in this study. Finally, we address the sustainable use of groundwater and subsurface environments for better future development and human well-being.

  14. Transient deformation of karst aquifers due to seasonal and multiyear groundwater variations observed by GPS in southern Apennines (Italy)

    Science.gov (United States)

    Silverii, Francesca; D'Agostino, Nicola; Métois, Marianne; Fiorillo, Francesco; Ventafridda, Gerardo

    2016-11-01

    We present GPS, hydrological, and GRACE (Gravity Recovery and Climate Experiment) observations in southern Apennines (Italy) pointing to a previously unnoticed response of the solid Earth to hydrological processes. Transient patterns in GPS horizontal time series near to large karst aquifers are controlled by seasonal and interannual phases of groundwater recharge/discharge of karst aquifers, modulating the extensional ˜3 mm/yr strain within the tectonically active Apennines. We suggest that transient signals are produced, below the saturation level of the aquifers and above a poorly constrained depth in the shallow crust, by time-dependent opening of subvertical, fluid-filled, conductive fractures. We ascribe this process to the immature karstification and intense tectonic fracturing, favoring slow groundwater circulation, and to multiyear variations of the water table elevation, influenced by variable seasonal recharge. The vertical component displays seasonal and multiyear signals more homogeneously distributed in space and closely correlated with estimates of total water storage from GRACE, reflecting the elastic response of the lithosphere to variations of surface water loads. The different sensitivities of vertical and horizontal components to the hydrologically induced deformation processes allow us to spatially and temporally resolve the different phases of the water cycle, from maximum hydrological loading at the surface to maximum hydrostatic pressure beneath karst aquifers. Finally, we suggest that transient deformation signals in the geodetic series of the Apennines are correlated to large-scale climatic patterns (Northern Atlantic Oscillation) through their influence on precipitation variability and trends at the regional scale.

  15. Modeling of groundwater draft based on satellite-derived crop acreage estimation over an arid region of northwest India

    Science.gov (United States)

    Bhadra, Bidyut Kumar; Kumar, Sanjay; Paliwal, Rakesh; Jeyaseelan, A. T.

    2016-11-01

    Over-exploitation of groundwater for agricultural crops puts stress on the sustainability of natural resources in the arid region of Rajasthan state, India. Hydrogeological study of groundwater levels of the study area during the pre-monsoon (May to June), post-monsoon (October to November) and post-irrigation (February to March) seasons of 2004-2005 to 2011-2012 shows a steady decline of groundwater levels at the rate of 1.28-1.68 m/year, mainly due to excessive groundwater draft for irrigation. Due to the low density of the groundwater observation-well network in the study area, assessment of groundwater draft, and thus groundwater resource management, becomes a difficult task. To overcome the situation, a linear groundwater draft model (LGDM) has been developed based on the empirical relationship between satellite-derived crop acreage and the observed groundwater draft for the year 2003-2004. The model has been validated for a decade, during three year-long intervals (2005-2006, 2008-2009 and 2011-2012) using groundwater draft, estimated through a discharge factor method. Further, the estimated draft was validated through observed pumping data from random sampled villages (2011-2012). The results suggest that the developed LGDM model provides a good alternative to the estimation of groundwater draft based on satellite-based crop area in the absence of groundwater observation wells in arid regions of northwest India.

  16. Water level observations from Unmanned Aerial Vehicles (UAVs) for improving probabilistic estimations of interaction between rivers and groundwater

    Science.gov (United States)

    Bandini, Filippo; Butts, Michael; Vammen Jacobsen, Torsten; Bauer-Gottwein, Peter

    2016-04-01

    Integrated hydrological models are generally calibrated against observations of river discharge and piezometric head in groundwater aquifers. Integrated hydrological models are rarely calibrated against spatially distributed water level observations measured by either in-situ stations or spaceborne platforms. Indeed in-situ observations derived from ground-based stations are generally spaced too far apart to capture spatial patterns in the water surface. On the other hand spaceborne observations have limited spatial resolution. Additionally satellite observations have a temporal resolution which is not ideal for observing the temporal patterns of the hydrological variables during extreme events. UAVs (Unmanned Aerial Vehicles) offer several advantages: i) high spatial resolution; ii) tracking of the water body better than any satellite technology; iii) timing of the sampling merely depending on the operators. In this case study the Mølleåen river (Denmark) and its catchment have been simulated through an integrated hydrological model (MIKE 11-MIKE SHE). This model was initially calibrated against observations of river discharge retrieved by in-situ stations and against piezometric head of the aquifers. Subsequently the hydrological model has been calibrated against dense spatially distributed water level observations, which could potentially be retrieved by UAVs. Error characteristics of synthetic UAV water level observations were taken from a recent proof-of-concept study. Since the technology for ranging water level is under development, UAV synthetic water level observations were extracted from another model of the river with higher spatial resolution (cross sections located every 10 m). This model with high resolution is assumed to be absolute truth for the purpose of this work. The river model with the coarser resolution has been calibrated against the synthetic water level observations through Differential Evolution Adaptive Metropolis (DREAM) algorithm, an

  17. Estimating pumping time and ground-water withdrawals using energy-consumption data. Water-Resources Investigation

    Energy Technology Data Exchange (ETDEWEB)

    Hurr, R.T.; Litke, D.W.

    1989-01-01

    Evaluation of the hydrology of an aquifer requires knowledge about the volume of ground water in storage and also about the volume of ground-water withdrawals. Totalizer flow meters may be installed at pumping plants to measure withdrawals; however, it generally is impractical to equip all wells in an area with meters. A viable alternative is the use of rate-time methods to estimate withdrawals. The relation between power demand and pumping rate at a pumping plant can be described through the use of the power-consumption coefficient. Where equipment and hydrologic conditions are stable, this coefficient can be applied to total energy consumption at a site to estimate total ground-water withdrawals. Random sampling of power-consumption coefficients can be used to estimate area-wide ground-water withdrawals.

  18. An Update of the Analytical Groundwater Modeling to Assess Water Resource Impacts at the Afton Solar Energy Zone

    Energy Technology Data Exchange (ETDEWEB)

    Quinn, John J. [Argonne National Lab. (ANL), Argonne, IL (United States); Greer, Christopher B. [Argonne National Lab. (ANL), Argonne, IL (United States); Carr, Adrianne E. [Argonne National Lab. (ANL), Argonne, IL (United States)

    2014-10-01

    The purpose of this study is to update a one-dimensional analytical groundwater flow model to examine the influence of potential groundwater withdrawal in support of utility-scale solar energy development at the Afton Solar Energy Zone (SEZ) as a part of the Bureau of Land Management’s (BLM’s) Solar Energy Program. This report describes the modeling for assessing the drawdown associated with SEZ groundwater pumping rates for a 20-year duration considering three categories of water demand (high, medium, and low) based on technology-specific considerations. The 2012 modeling effort published in the Final Programmatic Environmental Impact Statement for Solar Energy Development in Six Southwestern States (Solar PEIS; BLM and DOE 2012) has been refined based on additional information described below in an expanded hydrogeologic discussion.

  19. Arsenic and Associated Trace Metals in Texas Groundwater

    Science.gov (United States)

    Lee, L.; Herbert, B. E.

    2002-12-01

    The value of groundwater has increased substantially worldwide due to expanding human consumption. Both the quantity and quality of groundwater are important considerations when constructing policies on natural resource conservation. This study is focused on evaluating groundwater quality in the state of Texas. Historical data from the Texas Water Development Board and the National Uranium Resource Evaluation were collected into a GIS database for spatial and temporal analyses. Specific attentions were placed on arsenic and other trace metals in groundwater. Recent studies in the United States have focused on isolated incidences of high arsenic occurrence, ignoring possible connections between arsenic and other trace metals. Descriptive statistics revealed strong correlations in groundwater between arsenic and other oxyanions including vanadium, selenium and molybdenum. Arsenic and associated trace metals were clustered at three physiographic hotspots, the Southern High Plains, the Gulf Coastal Plains of Texas, and West Texas. A geologic survey showed that arsenic and other trace metals in Texas groundwater follow local geologic trends. Uranium deposits and associated mineralization were found to occur in the same physiographic locations. Uranium mineralization may be a significant natural source of arsenic and other trace metals in Texas groundwater. Recharge, evaporative concentration, and aquifer characteristics were also contributing factors to the occurrence of trace metals in Texas groundwater. Spatial statistics were used to delineate natural sources from anthropogenic inputs. Similarly, the natural background was estimated from the spatial distribution of trace metal observations in Texas groundwater.

  20. Resource conservation and recovery act ground-water monitoring projects for Hanford facilities: Progress report, January 1--March 31, 1989

    Energy Technology Data Exchange (ETDEWEB)

    Smith, R.M.; Bates, D.J.; Lundgren, R.E.

    1989-06-01

    This document describes the progress of 13 Hanford Site ground-water monitoring projects for the period January 1 to March 31, 1989. The work described in this document is conducted by the Pacific Northwest Laboratory under the management of Westinghouse Hanford Company for the US Department of Energy. Concentrations of ground-water constituents are compared to federal drinking water standards throughout this document for reference purposes. All drinking water supplied from the sampled aquifer meets regulatory standards for drinking water quality. 32 refs., 30 figs., 103 tabs.

  1. Palaeoclimatic and deforestation effect on the coastal fresh groundwater resources of SE Ivory Coast from isotopic and chemical evidence

    Science.gov (United States)

    Adiaffi, Bernard; Marlin, Christelle; Oga, Yéï Marie Solange; Massault, Marc; Noret, Aurelie; Biemi, Jean

    2009-05-01

    SummaryIn the South-east of the Ivory Coast, two aquifer systems have been studied in the sedimentary deposits at the South and in the fractured bedrock at the North of the study area (5-6°N, 2.40-4.40°W) : (1) the Continental Terminal (CT) and (2) the Paleoproterozoïc Bedrock (PB). In the studied area, the vegetation cover has undergone significant changes since 1955 in addition to climate change. Rainforests have gradually disappeared due to natural and anthropological deforestation. The impact of deforestation on groundwater of the PB and on the CT has been studied by a geochemical approach. Stable isotopes ( 18O, 2H and 13C) contents, radiocarbon ( 14C) contents and chemical data (major ions) have been measured on a set of 25 groundwater samples. The residence time of the groundwaters is estimated with the 14C using two models: (i) the model of well-mixed reservoir (WMR model) and (ii) the piston flow model (PF model). The range of the PB groundwater residence time (15,200-8300 to ˜300-100 a BP) for both models shows that the recharge has started at the beginning of the post-glacial period whereas the CT aquifer recharge is much more recent (from 300 a BP to today). The PB groundwater provides information about paleoclimatic conditions that occurred over the studied area during the late Pleistocene. The low contents indicate cold and/or more humid conditions of recharge. During that period, the low content of 13C is consistent with a vegetation cover dominated by rainforest (C 3 plants). After the 20th century, the progressive evolution of vegetation cover from forest to cultivated plants and grasses is shown by the enrichment of groundwater in 13C (C 3 plants to C 4 plants). The relatively high mineralization level (mean of 143.7 mg L -1) and high δ18O- δ2H values of modern PB groundwater reflect of a recharge process that is slowed by a thick layer (16.3-72.5 m) of weathered formations above the PB formations. Groundwaters of the CT aquifer are

  2. A technique for estimating ground-water levels at sites in Rhode Island from observation-well data

    Science.gov (United States)

    Socolow, Roy S.; Frimpter, Michael H.; Turtora, Michael; Bell, Richard W.

    1994-01-01

    Estimates of future high, median, and low ground- water levels are needed for engineering and architectural design decisions and for appropriate selection of land uses. For example, the failure of individual underground sewage-disposal systems due to high ground-water levels can be prevented if accurate water-level estimates are available. Estimates of extreme or average conditions are needed because short duration preconstruction obser- vations are unlikely to be adequately represen- tative. Water-level records for 40 U.S. Geological Survey observation wells in Rhode Island were used to describe and interpret water-level fluctuations. The maximum annual range of water levels average about 6 feet in sand and gravel and 11 feet in till. These data were used to develop equations for estimating future high, median, and low water levels on the basis of any one measurement at a site and records of water levels at observation wells used as indexes. The estimating technique relies on several assumptions about temporal and spatial variations: (1) Water levels will vary in the future as they have in the past, (2) Water levels fluctuate seasonally (3) Ground-water fluctuations are dependent on site geology, and (4) Water levels throughout Rhode Island are subject to similar precipitation and climate. Comparison of 6,697 estimates of high, median, and low water levels (depth to water level exceeded 95, 50, and 5 percent of the time, respectively) with the actual measured levels exceeded 95, 50, and 5 percent of the time at 14 sites unaffected by pumping and unknown reasons, yielded mean squared errors ranging from 0.34 to 1.53 square feet, 0.30 to 1.22 square feet, and 0.32 to 2.55 square feet, respectively. (USGS)

  3. Regional Groundwater Processes and Flow Dynamics from Age Tracer Data

    Science.gov (United States)

    Morgenstern, Uwe; Stewart, Mike K.; Matthews, Abby

    2016-04-01

    Age tracers are now used in New Zealand on regional scales for quantifying the impact and lag time of land use and climate change on the quantity and quality of available groundwater resources within the framework of the National Policy Statement for Freshwater Management 2014. Age tracers provide measurable information on the dynamics of groundwater systems and reaction rates (e.g. denitrification), essential for conceptualising the regional groundwater - surface water system and informing the development of land use and groundwater flow and transport models. In the Horizons Region of New Zealand, around 200 wells have tracer data available, including tritium, SF6, CFCs, 2H, 18O, Ar, N2, CH4 and radon. Well depths range from shallower wells in gravel aquifers in the Horowhenua and Tararua districts, and deeper wells in the aquifers between Palmerston North and Wanganui. Most of the groundwater samples around and north of the Manawatu River west of the Tararua ranges are extremely old (>100 years), even from relatively shallow wells, indicating that these groundwaters are relatively disconnected from fresh surface recharge. The groundwater wells in the Horowhenua tap into a considerably younger groundwater reservoir with groundwater mean residence time (MRT) of 10 - 40 years. Groundwater along the eastern side of the Tararua and Ruahine ranges is significantly younger, typically groundwater recharge rates, as deduced from groundwater depth and MRT, are extremely low in the central coastal area, consistent with confined groundwater systems, or with upwelling of old groundwater close to the coast. Very low vertical recharge rates along the Manawatu River west of the Manawatu Gorge indicate upwelling groundwater conditions in this area, implying groundwater discharge into the river is more likely here than loss of river water into the groundwater system. High recharge rates observed at several wells in the Horowhenua area and in the area east of the Tararua and

  4. Earth Resources Observation and Science (EROS) Center's Landsat State Mosaics Gallery

    Data.gov (United States)

    National Aeronautics and Space Administration — The Earth Resources Observation and Science (EROS) Center manages the this gallery of images of the 50 U.S. states plus Puerto Rico as derived by Landsat data.

  5. Earth Resources Observation and Science (EROS) Center's Earth as Art Image Gallery 2

    Data.gov (United States)

    National Aeronautics and Space Administration — The Earth Resources Observation and Science (EROS) Center manages this collection of forty-five new scenes developed for their aesthetic beauty, rather than for...

  6. Earth Resources Observation and Science (EROS) Center's Journey of Lewis and Clark Gallery

    Data.gov (United States)

    National Aeronautics and Space Administration — The Earth Resources Observation and Science (EROS) Center manages the this gallery of Landsat-derived images of one of the most remarkable and productive scientific...

  7. Earth Resources Observation and Science (EROS) Center's Earth as Art Image Gallery 3

    Data.gov (United States)

    National Aeronautics and Space Administration — The Earth Resources Observation and Science (EROS) Center manages the Earth as Art Three exhibit, which provides fresh and inspiring glimpses of different parts of...

  8. THE IMPACT OF HUMAN ACTIVITIES ON GROUNDWATER RESOURCES IN THE SOUTH EDGE OF TARIM BASIN,XINJIANG

    Institute of Scientific and Technical Information of China (English)

    MAJin-zhu; LAITian-wen; 等

    2002-01-01

    In the modern times ,the population growth,development of industrial and agricultural production and the petroleum exploitation,brought about the unceasing expansion of artificial oasis and abrupt increase of water demand .The artificial hydraulic irrigation engineering took the place of the natural river systerm,the reservoirs took the placeof natural lakds,which in turn enhanced the space-time redistribution of surface water based on the natural evolution,and so did groundwater.The groundwater recharge reduced 26.2% in 46 years from 1950 to 1995 in the southern piedmont fold plain of Tarim Basin due to mean yearly population increase rate of 27.7‰ and associated with the water use rate increasing from 24.6% to 58.4%.At the same time the artificial water system seepage give primary play to groundwater recharge,which is up to 57.6% whilst that of the natural system reduce to 33.7%.As a result,groundwater level drop 3-5m widespread except some irrigation area and surrounding of plain reservoir.Sping water discharge also reduce about 37.6% and discharge some continuously move away to the north with the value of 0.5-1.2km in the past 40 years.

  9. Coastal forests and groundwater: Using case studies to understand the effects of drivers and stressors for resource management

    Science.gov (United States)

    Timothy Callahan; Devendra Amatya; Peter Stone

    2017-01-01

    Forests are receiving more attention for the ecosystem goods and services they provide and the potential change agents that may affect forest health and productivity. Highlighting case examples from coastal forests in South Carolina, USA, we describe groundwater processes with respect to stressors and potential responses of a wetland-rich forested landscape,...

  10. Wet deposition of air pollution at southwest monsoon outbreak and its impact on groundwater resources of Greater Kochi region

    Digital Repository Service at National Institute of Oceanography (India)

    Joseph, T.; Nair, M.; Balachandran, K.K.; Nair, K.K.C.

    the industrial impact; the possibility of nutrient enriched rainwater peeping into groundwater seems to be a reality. The PO sub(4) and NH sub(4) levels remained high at refinery and fertilizer complex. The enriching effect of PO sub(4) by emissions declines...

  11. Understanding the past to interpret the future: comparison of simulated groundwater recharge in the upper Colorado River basin (USA) using observed and general-circulation-model historical climate data

    Science.gov (United States)

    Tillman, Fred D.; Gangopadhyay, Subhrendu; Pruitt, Tom

    2016-10-01

    In evaluating potential impacts of climate change on water resources, water managers seek to understand how future conditions may differ from the recent past. Studies of climate impacts on groundwater recharge often compare simulated recharge from future and historical time periods on an average monthly or overall average annual basis, or compare average recharge from future decades to that from a single recent decade. Baseline historical recharge estimates, which are compared with future conditions, are often from simulations using observed historical climate data. Comparison of average monthly results, average annual results, or even averaging over selected historical decades, may mask the true variability in historical results and lead to misinterpretation of future conditions. Comparison of future recharge results simulated using general circulation model (GCM) climate data to recharge results simulated using actual historical climate data may also result in an incomplete understanding of the likelihood of future changes. In this study, groundwater recharge is estimated in the upper Colorado River basin, USA, using a distributed-parameter soil-water balance groundwater recharge model for the period 1951-2010. Recharge simulations are performed using precipitation, maximum temperature, and minimum temperature data from observed climate data and from 97 CMIP5 (Coupled Model Intercomparison Project, phase 5) projections. Results indicate that average monthly and average annual simulated recharge are similar using observed and GCM climate data. However, 10-year moving-average recharge results show substantial differences between observed and simulated climate data, particularly during period 1970-2000, with much greater variability seen for results using observed climate data.

  12. Understanding the past to interpret the future: comparison of simulated groundwater recharge in the upper Colorado River basin (USA) using observed and general-circulation-model historical climate data

    Science.gov (United States)

    Tillman, Fred D.; Gangopadhyay, Subhrendu; Pruitt, Tom

    2017-03-01

    In evaluating potential impacts of climate change on water resources, water managers seek to understand how future conditions may differ from the recent past. Studies of climate impacts on groundwater recharge often compare simulated recharge from future and historical time periods on an average monthly or overall average annual basis, or compare average recharge from future decades to that from a single recent decade. Baseline historical recharge estimates, which are compared with future conditions, are often from simulations using observed historical climate data. Comparison of average monthly results, average annual results, or even averaging over selected historical decades, may mask the true variability in historical results and lead to misinterpretation of future conditions. Comparison of future recharge results simulated using general circulation model (GCM) climate data to recharge results simulated using actual historical climate data may also result in an incomplete understanding of the likelihood of future changes. In this study, groundwater recharge is estimated in the upper Colorado River basin, USA, using a distributed-parameter soil-water balance groundwater recharge model for the period 1951-2010. Recharge simulations are performed using precipitation, maximum temperature, and minimum temperature data from observed climate data and from 97 CMIP5 (Coupled Model Intercomparison Project, phase 5) projections. Results indicate that average monthly and average annual simulated recharge are similar using observed and GCM climate data. However, 10-year moving-average recharge results show substantial differences between observed and simulated climate data, particularly during period 1970-2000, with much greater variability seen for results using observed climate data.

  13. Groundwater and climate change: mitigating the global groundwater crisis and adapting to climate change model

    Science.gov (United States)

    To better understand the effects of climate change on global groundwater resources, the United Nations Educational, Scientific, and Cultural Organization (UNESCO) International Hydrological Programme (IHP) initiated the GRAPHIC (Groundwater Resources Assessment under the Pressures of Humanity and Cl...

  14. Evaluation of Groundwater Storage changes at Konya Closed Basin, Turkey using GRACE-based and in-situ measurements

    Science.gov (United States)

    Kamil Yilmaz, Koray; Saber, Mohamed; Tugrul Yilmaz, Mustafa

    2016-04-01

    The Konya Closed Basin (KCB) located in Central Anatolia, Turkey, is the primary grain producer in Turkey. The lack of sufficient surface water resources and recently changing crop patterns have led to over-exploitation of groundwater resources and resulted in significant drop in groundwater levels. For this reason monitoring of the groundwater storage change in this region is critical to understand the potential of the current water resources and to devise effective water management strategies to avoid further depletion of the groundwater resources. Therefore, the main objective of this study is to examine and assess the utility of the Gravity Recovery and Climate Experiment (GRACE) and the Global Land Data Assimilation System (GLDAS) to monitor and investigate the groundwater storage changes in the Konya Closed Basin. Groundwater storage changes are derived using GRACE and GLDAS data and then are compared with the groundwater changes derived from the observed groundwater levels. The initial results of the comparison indicate an acceptable agreement between declining trends in GRACE-based and observed groundwater storage change during the study time period (2002 to 2015). Additionally, the results indicated that the study region exhibited remarkable drought conditions during 2007-2008 period. This study shows that the GRACE/GLDAS datasets can be used to monitor the equivalent groundwater storage changes which is crucial for long-term effective water management strategies.

  15. The Influence of Pumping on Observed Bacterial Counts in Groundwater Samples: Implications for Sampling Protocol and Water Quality Interpretation

    Science.gov (United States)

    Kozuskanich, J.; Novakowski, K.; Anderson, B.

    2008-12-01

    Drinking water quality has become an important issue in Ontario following the events in Walkerton in 2000. Many rural communities are reliant on private groundwater wells for drinking water, and it is the responsibility of the owner to have the water tested to make sure it is safe for human consumption. Homeowners can usually take a sample to the local health unit for total coliform and E. Coli analysis at no charge to determine if the water supply is being tainted by surface water or fecal matter, both of which could indicate the potential for negative impacts on human health. However, is the sample coming out of the tap representative of what is going on the aquifer? The goal of this study is to observe how bacterial counts may vary during the course of well pumping, and how those changing results influence the assessment of water quality. Multiple tests were conducted in bedrock monitoring wells to examine the influence of pumping rate and pumped volume on observed counts of total coliform, E. Coli, fecal streptococcus, fecal coliform and heterotrophic plate count. Bacterial samples were collected frequently during the course of continuous purging events lasting up to 8 hours. Typical field parameters (temperature, salinity, pH, dissolved oxygen and ORP) were also continuously monitored during the course of each test. Common practice in groundwater studies is to wait until these parameters have stabilized or three well volumes have been removed prior to sampling, to ensure the sample is taken from new water entering the well from the aquifer, rather than the original water stored in the borehole prior to the test. In general, most bacterial counts were low, but did go above the drinking water standard of 0 counts/100mL (total coliform and E. Coli) at times during the tests. Results show the greatest variability in the observed bacterial counts at the onset of pumping prior to the removal of three well volumes. Samples taken after the removal of three well

  16. Modelling small groundwater systems - the role of targeted field investigations and observational data in reducing model uncertainty

    Science.gov (United States)

    Abesser, Corinna; Hughes, Andrew; Boon, David

    2017-04-01

    Coastal dunes are delicate systems that are under threat from a variety of human and natural influences. Groundwater modelling can provide a better understanding of how these systems operate and can be a useful tool towards the effective management of a coastal dune system, e.g. through predicting impacts from climatic change, sea level rise and land use management. Because of their small size, typically 10 - 100 km2, models representing small dune aquifer systems are more sensitive to uncertainties in input data, model geometry and model parameterisation as well as to the availability of observational data. This study describes the development of a groundwater flow model for a small (8 km2) spit dune system, Braunton Burrows, on the Southwest coast of England, UK. The system has been extensively studied and its hydrology is thought to be well understood. However, model development revealed a high degree of uncertainty relating to model structure (definition of model boundary conditions) and parameterisation (e.g., transmissivity distributions within the model domain). An iterative approach was employed, integrating (1) sensitivity analyses, (2) targeted field investigations and (3) Monte Carlo simulations within a cycle of repeated interrogation of the model outputs, observed data and conceptual understanding. Assessment of "soft information" and targeted field investigations were an important part of this iterative modelling process. For example, a passive seismic survey (TROMINO®) provided valuable new data for the characterisation of concealed bedrock topography and thickness of superficial deposits. The data confirmed a generally inclined underlying wave cut rock shelf platform (as suggested by literature sources), revealed a buried valley, and led to a more detailed delineation of transmissivity zones within the model domain. Constructing models with increasingly more complex spatial distributions of transmissivity, resulted in considerable improvements in

  17. The Use Of Electromagnetic And Electrical Resistivity Methods In Assessing Groundwater Resource Potentials In Adoe Sunyani Ghana.

    Directory of Open Access Journals (Sweden)

    Alfred K. Bienibuor

    2015-08-01

    Full Text Available Electromagnetic and electrical resistivity geophysical methods were used to map out potential groundwater sites for boreholes drilling in the Adoe community in the Sunyani west district of Ghana. The electromagnetic data was taken with the Geonics EM-34 conductivity meter while the electrical resistivity data was taken with the ABEM SAS 1000 C Terrameter using the Schlumberger electrode configuration. Results from the measurements revealed four subsurface geological layers of the following resistivity and thickness ranges quartzitic sandstone with clay 42-118 amp937m 1-2.2 m sandy clay with silt 27-487 amp937m 9-12 m lateritic sandstone 13-728 amp937m 6-14 m and clayey shale 20-29 amp937m 6-14 m The overburden ranged in thickness from 14 m to 24 m. Sites selected for borehole drilling had a groundwater yield range of 0.94 -12 m3h.

  18. Simulating the impact of climate change on the groundwater resources of the Magdalen Islands, Québec, Canada

    Directory of Open Access Journals (Sweden)

    Jean-Michel Lemieux

    2015-03-01

    New hydrological insights for the region: The simulation results show that among the three impacts considered, the most important is sea-level rise, followed by decreasing groundwater recharge and coastal erosion. When combined, these impacts cause the saltwater–freshwater interface to migrate inland over a distance of 37 m and to rise by 6.5 m near the coast to 3.1 m further inland, over a 28-year period.

  19. Ground-water resources in the lower Milliken--Sarco--Tulucay Creeks area, southeastern Napa County, California, 2000-2002

    Science.gov (United States)

    Farrar, Christopher D.; Metzger, Loren F.

    2003-01-01

    Ground water obtained from individual private wells is the sole source of water for about 4,800 residents living in the lower Milliken-Sarco-Tulucay Creeks area of southeastern Napa County. Increases in population and in irrigated vineyards during the past few decades have increased water demand. Estimated ground-water pumpage in 2000 was 5,350 acre-feet per year, an increase of about 80 percent since 1975. Water for agricultural irrigation is the dominant use, accounting for about 45 percent of the total. This increase in ground-water extraction has resulted in the general decline of ground-water levels. The purpose of this report is to present selected hydrologic data collected from 1975 to 2002 and to quantify changes in the ground-water system during the past 25 years. The study area lies in one of several prominent northwest-trending structural valleys in the North Coast Ranges. The area is underlain by alluvial deposits and volcanic rocks that exceed 1,000 feet in thickness in some places. Alluvial deposits and tuff beds in the volcanic sequence are the principal source of water to wells. The ground-water system is recharged by precipitation that infiltrates, in minor amounts, directly on the valley floor but mostly by infiltration in the Howell Mountains. Ground water moves laterally from the Howell Mountains into the study area. Although the area receives abundant winter precipitation in most years, nearly half of the precipitation is lost as surface runoff to the Napa River. Evapotranspiration also is high, accounting for nearly one-half of the total precipitation received. Because of the uncertainties in the estimates of precipitation, runoff, and evapotranspiration, a precise estimate of potential ground-water recharge cannot be made. Large changes in ground-water levels occurred between 1975 and 2001. In much of the western part of the area, water levels increased; but in the central and eastern parts, water levels declined by 25 to 125 feet. Ground-water

  20. Redox Roll-Front Mobilization of Geogenic Uranium by Nitrate Input into Aquifers: Risks for Groundwater Resources.

    Science.gov (United States)

    van Berk, Wolfgang; Fu, Yunjiao

    2017-01-03

    Redox conditions are seen as the key to controlling aqueous uranium concentrations (cU(aq)). Groundwater data collected by a state-wide groundwater quality monitoring study in Mecklenburg-Western Pomerania (Germany) reveal peak cU(aq) up to 75 μg L(-1) but low background uranium concentrations (median cU(aq) aquifer depth and performed semigeneric 2D reactive mass transport modeling which is based on chemical thermodynamics. The combined interpretation of modeling results and measured data reveals that high cU(aq) and its depth-specific distribution depending on redox conditions is a result of a nitrate-triggered roll-front mobilization of geogenic uranium in the studied aquifers which are unaffected by nuclear activities. The modeling results show that groundwater recharge containing (fertilizer-derived) nitrate drives the redox shift from originally reducing toward oxidizing environments, when nitrate input has consumed the reducing capacity of the aquifers, which is present as pyrite, degradable organic carbon, and geogenic U(IV) minerals. This redox shift controls the uranium roll-front mobilization and results in high cU(aq) within the redoxcline. Moreover, the modeling results indicate that peak cU(aq) occurring at this redox front increase along with the temporal progress of such redox conversion within the aquifer.

  1. Water level observations from Unmanned Aerial Vehicles for improving estimates of surface water-groundwater interaction

    DEFF Research Database (Denmark)

    Bandini, Filippo; Butts, Michael; Vammen Jacobsen, Torsten

    2017-01-01

    . However, traditional river gauging stations are normally spaced too far apart to capture spatial patterns in the water surface, while spaceborne observations have limited spatial and temporal resolution. UAVs (Unmanned Aerial Vehicles) can retrieve river water level measurements, providing: i) high...

  2. TIGER-NET – enabling an Earth Observation capacity for Integrated Water Resource Management in Africa

    DEFF Research Database (Denmark)

    Walli, A.; Tøttrup, C.; Naeimi, V.

    -source Water Observation and Information Systems (WOIS) for monitoring, assessing and inventorying water resources in a cost-effective manner; 2. Capacity building and training of African water authorities and technical centers to fully exploit the increasing observation capacity offered by current...

  3. TIGER-NET – enabling an Earth Observation capacity for Integrated Water Resource Management in Africa

    DEFF Research Database (Denmark)

    Walli, A.; Tøttrup, C.; Naeimi, V.

    and upcoming generations of satellites, including the Sentinel missions. Dedicated application case studies have been developed and demonstrated covering all EO products required by and developed with the participating African water authorities for their water resource management tasks, such as water reservoir......As part of the TIGER initiative [1] the TIGER-NET project aims to support the assessment and monitoring of water resources from watershed to transboundary basin level delivering indispensable information for Integrated Water Resource Management in Africa through: 1. Development of an open......-source Water Observation and Information Systems (WOIS) for monitoring, assessing and inventorying water resources in a cost-effective manner; 2. Capacity building and training of African water authorities and technical centers to fully exploit the increasing observation capacity offered by current...

  4. Impacts of varying agricultural intensification on crop yield and groundwater resources: comparison of the North China Plain and US High Plains

    Science.gov (United States)

    Pei, Hongwei; Scanlon, Bridget R.; Shen, Yanjun; Reedy, Robert C.; Long, Di; Liu, Changming

    2015-04-01

    Agricultural intensification is often considered the primary approach to meet rising food demand. Here we compare impacts of intensive cultivation on crop yield in the North China Plain (NCP) with less intensive cultivation in the US High Plains (USHP) and associated effects on water resources using spatial datasets. Average crop yield during the past decade from intensive double cropping of wheat and corn in the NCP was only 15% higher than the yield from less intensive single cropping of corn in the USHP, although nitrogen fertilizer application and percent of cropland that was irrigated were both ˜2 times greater in the NCP than in the USHP. Irrigation and fertilization in both regions have depleted groundwater storage and resulted in widespread groundwater nitrate contamination. The limited response to intensive management in the NCP is attributed in part to the two month shorter growing season for corn to accommodate winter wheat than that for corn in the USHP. Previous field and modeling studies of crop yield in the NCP highlight over application of N and water resulting in low nitrogen and water use efficiencies and indicate that cultivars, plant densities, soil fertility and other factors had a much greater impact on crop yields over the past few decades. The NCP-USHP comparison along with previous field and modeling studies underscores the need to weigh the yield returns from intensive management relative to the negative impacts on water resources. Future crop management should consider the many factors that contribute to yield along with optimal fertilization and irrigation to further increase crop yields while reducing adverse impacts on water resources.

  5. The National Danish Water Resources Model - using an integrated groundwater - surface water model for decision support and WFD implementation in a changing climate

    Science.gov (United States)

    Lajer Hojberg, Anker; Hinsby, Klaus; Jørgen Henriksen, Hans; Troldborg, Lars

    2014-05-01

    Integrated and sustainable water resources management and development of river basin management plans according to the Water Framework Directive is getting increasingly complex especially when taking projected climate change into account. Furthermore, uncertainty in future developments and incomplete knowledge of the physical system introduces a high degree of uncertainty in the decision making process. Knowledge based decision making is therefore vital for formulation of robust management plans and to allow assessment of the inherent uncertainties. The Department of Hydrology at the Geological Survey of Denmark and Greenland started in 1996 to develop a mechanistically, transient and spatially distributed groundwater-surface water model - the DK-model - for the assessment of groundwater quantitative status accounting for interactions with surface water and anthropogenic changes, such as extraction strategies and land use, as well as climate change. The model has been subject to continuous update building on hydrogeological knowledge established by the regional water authorities and other national research institutes. With the on-going improvement of the DK-model it is now increasingly applied both by research projects and for decision support e.g. in implementation of the Water Framework Directive or to support other decisions related to protection of water resources (quantitative and chemical status), ecosystems and the built environment. At present, the DK-model constitutes the backbone of a strategic modelling project funded by the Danish Environmental Protection Agency, with the aim of developing a modelling complex that will provide the foundation of the implementation of the Water Framework Directive. Since 2003 the DK-model has been used in more than 25 scientific papers and even more public reports. In the poster and the related review paper we describe the most important applications in both science and policy, where the DK-model has been used either

  6. Investigating the impact of global climatic and landuse changes on groundwater resources in hard rock areas of South India

    Science.gov (United States)

    Ferrant, S.; Perrin, J.; Marechal, J.; Dewandel, B.; Aulong, S.; Ahmed, S.

    2010-12-01

    In most parts of India, and particularly in South India, groundwater levels are hazardously declining, while agricultural groundwater use is increasing. The current issue is to address the probable evolution of water table levels in relation with climate and agricultural changes. The aim of the SHIVA-ANR project (http://www.shiva-anr.org) is to provide some indicators of the water availability at the village scale to evaluate the vulnerability of farmers facing global changes. This study focuses on a particularly water stressed semi-arid area of South India characterized by hard rock geology with naturally low recharge capacity and limited surface water availability. The study catchment is located in the agricultural area of the Kudaliar river watershed (980km^2) located 50 km north of Hyderabad, India. It is composed of about 120 villages. Socio economic surveys have been carried out at the village scale to evaluate the present socio-economic situation of farmers. It also provides more details on various cultural and irrigation practices at this scale. The landuse has been evaluated by remote sensing with two satellite images, one after monsoon (October 2009), and the other during dry season (March 2010). Groundwater-irrigated rice paddies represent about 10% of the area, whereas rainfed crop (corn and cotton) represent about 45%. Numerous small tanks (reservoir) situated on the river network define a water harvesting system of 2% of the catchment area which captures surface runoff during monsoon. No discharges data are available at the outlet, as the river is dry most of the year. A hydro-geological survey has been carried out to provide a map of aquifer thickness and the general state of the groundwater level before and after monsoon. The Soil Water Assessment Tool model (SWAT) has been calibrated to assess the water budget of the agricultural catchment under present conditions. Soil parameters calibration is made first on seasonal groundwater recharge for

  7. Hydrochemical characterization of various surface water and groundwater resources available in Matahara areas, Fantalle Woreda of Oromiya region

    Directory of Open Access Journals (Sweden)

    Megersa Olumana Dinka

    2015-03-01

    New hydrological insights for the region: Overall, the study result elucidates that the chemical composition of different water bodies are due to natural processes and/or anthropogenic activities within the region. The local anthropogenic processes could be discharges from factory, domestic sewage and farming activities. Some of the water types are found to have relatively higher concentration of dissolved constituents. Irrigation waters have almost equal chemical compositions, indicating their hydrochemical sources are almost the same. Most of the concentrations are relatively high in Lake Basaka, groundwater and hot springs. It is easy to imagine the potential damaging effects of such quality waters on crop production, soil properties and environment of the region.

  8. Groundwater geochemistry observations in littoral caves of Mallorca (western Mediterranean: implications for deposition of phreatic overgrowths on speleothems

    Directory of Open Access Journals (Sweden)

    Bogdan P. Onac

    2014-05-01

    Full Text Available Phreatic overgrowths on speleothems (POS precipitate at the air-water interface in the littoral caves of Mallorca, Spain. Mainly composed of calcite, aragonite POS are also observed in specific locations. To characterize the geochemical environment of the brackish upper water column, water samples and salinity values were collected from water profiles (0-2.9 m in April 2012 and March 2013 near aragonite POS in Cova des Pas de Vallgornera and calcite POS in Coves del Drac (hereafter, Vallgornera and Drac. Degassing of CO2 from the water was evidenced by the existence of lower dissolved inorganic carbon (DIC concentration and enriched δ13CDIC values in a thin surface layer (the uppermost 0.4 m, which was observed in both profiles from Drac. This process is facilitated by the efficient exchange of cave air with the atmosphere, creating a CO2 partial pressure (pCO2 disparity between the cave water and air, resulting in the precipitation of calcite POS as CO2 degasses from the water. The degassed upper layer was not observed in either profile from Vallgornera, suggesting that less efficient cave ventilation restricts outgassing of CO2, which also results in accumulation of CO2 in the cave atmosphere. The presence of an existing uncorroded POS horizon, as well as higher concentrations and large amplitude fluctuations of cave air pCO2, may indicate that aragonite POS deposition is currently episodic in Vallgornera. Ion concentration data from monthly water samples collected in each cave between October 2012 and March 2013 indicate higher Mg:Ca, Sr:Ca, Ba:Ca and Sr:Mg ratios in Vallgornera. Salinity alone does not appear to be a viable proxy for ions that may promote aragonite precipitation or inhibit calcite precipitation. Instead, these ions may be contributed by more intense bedrock weathering or deep groundwater flow.

  9. Groundwater Waters

    Directory of Open Access Journals (Sweden)

    Ramón Llamas

    1999-10-01

    Full Text Available The groundwaters released through springs constituted a basic element for the survival and progressive development of human beings. Man came to learn how to take better advantage of these waters by digging wells, irrigation channels, and galleries. Nevertheless, these activities do not require cooperation nor the collective agreement of relatively large groups of people, as in the case of creating the necessary structures to take advantage of the resources of surfacewaters. The construction and operation of these structures was a powerful factor in the birth of an urban or civil society – the designated water civilizations. The difference between people taking advantage of groundwater, quasi-individually, and those of surface water, where people work in a group, has continued to the present day. Whereas earlier, this difference did not bring about any special problems, the technological advances of this century, especially theturbine pump, have led to a spectacular increase in the use of roundwater. This advance has significantly contributed to reducing hunger in the world and has provided potable water in developing countries. However, the almost generalized lack of planning and control in the exploitation of these groundwaters reflects that they are little or badly understood by the managers of water policy in almost every country. As such, problems have occurred which have often become exaggerated, giving rise to water-myths. These problems, though, should be addressed if the aim is the sustainable usage of surface water as well as groundwater. To counter any misconceptions and to seek solutions to the problems, distinct plans of action can be highlighted: educating the public; fomenting a system of participative management and decisive support for the communities of users of subterranean waters; integrating a sufficient number of experts in hydrology in the various water management organizations;and assuring transparency of the data on

  10. SEASONAL VARIATIONS IN GROUNDWATER QUALITY OF VALSAD DISTRICT OF SOUTH GUJARAT (INDIA

    Directory of Open Access Journals (Sweden)

    P. Shroff

    2015-05-01

    Full Text Available Groundwater is an important precious natural resource. For optimum utilization of water resources, it is necessary to know both the quality as well as quantity of water. The present investigation is focused on seasonal variation in groundwater quality of Valsad district of south Gujarat (India. Groundwater samples from fifteen sampling stations were collected for two year i.e. from Aug 2007 to July 2009 and analyzed for pH, Colour, Total Hardness (TH, Calcium (Ca, Magnesium (Mg, Total Alkalinity (TA, Chloride and Sodium. Marginally higher level was observed in almost all parameters in summer season. No significant change observed in pH, Colour and Calcium.

  11. Groundwater and Terrestrial Water Storage

    Science.gov (United States)

    Rodell, Matthew; Chambers, Don P.; Famiglietti, James S.

    2011-01-01

    Most people think of groundwater as a resource, but it is also a useful indicator of climate variability and human impacts on the environment. Groundwater storage varies slowly relative to other non-frozen components of the water cycle, encapsulating long period variations and trends in surface meteorology. On seasonal to interannual timescales, groundwater is as dynamic as soil moisture, and it has been shown that groundwater storage changes have contributed to sea level variations. Groundwater monitoring well measurements are too sporadic and poorly assembled outside of the United States and a few other nations to permit direct global assessment of groundwater variability. However, observational estimates of terrestrial water storage (TWS) variations from the GRACE satellites largely represent groundwater storage variations on an interannual basis, save for high latitude/altitude (dominated by snow and ice) and wet tropical (surface water) regions. A figure maps changes in mean annual TWS from 2009 to 2010, based on GRACE, reflecting hydroclimatic conditions in 2010. Severe droughts impacted Russia and the Amazon, and drier than normal weather also affected the Indochinese peninsula, parts of central and southern Africa, and western Australia. Groundwater depletion continued in northern India, while heavy rains in California helped to replenish aquifers that have been depleted by drought and withdrawals for irrigation, though they are still below normal levels. Droughts in northern Argentina and western China similarly abated. Wet weather raised aquifer levels broadly across western Europe. Rains in eastern Australia caused flooding to the north and helped to mitigate a decade long drought in the south. Significant reductions in TWS seen in the coast of Alaska and the Patagonian Andes represent ongoing glacier melt, not groundwater depletion. Figures plot time series of zonal mean and global GRACE derived non-seasonal TWS anomalies (deviation from the mean of

  12. Groundwater: Illinois' Buried Treasure. Education Activity Guide.

    Science.gov (United States)

    Environmental Education Association of Illinois, Chicago.

    Groundwater is an extremely valuable resource that many feel has been too long neglected and taken for granted. There is growing recognition in Illinois and throughout the United States that comprehensive groundwater protection measures are vital. Illinois embarked on a course in protecting groundwater resources with the passage of the Illinois…

  13. Groundwater: Illinois' Buried Treasure. Education Activity Guide.

    Science.gov (United States)

    Environmental Education Association of Illinois, Chicago.

    Groundwater is an extremely valuable resource that many feel has been too long neglected and taken for granted. There is growing recognition in Illinois and throughout the United States that comprehensive groundwater protection measures are vital. Illinois embarked on a course in protecting groundwater resources with the passage of the Illinois…

  14. A numerical model to evaluate potential impacts of sea-level rise on groundwater resources in the Delaware coastal plain

    Science.gov (United States)

    He, C.; McKenna, T. E.; Wang, L.

    2013-12-01

    Sea level rise on the U.S. East Coast has accelerated much faster than in other parts of the world. In Delaware, the estimated sea level could rise as high as 1.5 meters by the year 2100 based on the information in IPCC (2007) and CCSP (2009). In this study, we used a 3-D variable-density groundwater flow model to study the movement of the fresh-water/salt-water interface and water table changes due to sea-level rise. Rather than developing a site-specific model, we analyzed the geospatial features of a serious of sub-watersheds along the coastline of the Delaware Estuary in Delaware using ArcGIS and constructed a representative model to capture the generalized flow patterns and saltwater intrusion rates that occur in typical area. Different scenarios with varying parameters were simulated. The simulation results were then applied to the Delaware River region to evaluate potential impacts of groundwater level changes on the potential land lose.

  15. Limits to global groundwater consumption

    Science.gov (United States)

    de Graaf, I.; Van Beek, L. P.; Sutanudjaja, E.; Wada, Y.; Bierkens, M. F.

    2016-12-01

    Groundwater is the largest accessible freshwater resource worldwide and is of critical importance for irrigation, and so for global food security. For many regions of the world where groundwater abstraction exceeds groundwater recharge, persistent groundwater depletion occurs. A direct consequence of depletion is falling groundwater levels, reducing baseflows to rivers, harming ecosystems. Also, pumping costs increase, wells dry up and land subsidence can occur. Water demands are expected to increase further due to growing population, economic development and climate change, posing the urgent question how sustainable current water abstractions are worldwide and where and when these abstractions approach conceivable limits with all the associated problems. Here, we estimated past and future trends (1960-2050) in groundwater levels resulting from changes in abstractions and climate and predicted when limits of groundwater consumption are reached. We explored these limits by predicting where and when groundwater levels drop that low that groundwater becomes unattainable for abstractions and how river flows are affected. Water availabilities, abstractions, and lateral groundwater flows are simulated (5 arcmin. resolution) using a coupled version of the global hydrological model PCR-GLOBWB and a groundwater model based on MODFLOW. The groundwater model includes a parameterization of the worlds confined and unconfined aquifer systems, needed for a realistic simulation of groundwater head dynamics. Results show that, next to the existing regions experiencing groundwater depletion (like India, Pakistan, Central Valley) new regions will develop, e.g. Southern Europe, the Middle East, and Africa. Using a limit that reflects present-day feasibility of groundwater abstraction, we estimate that in 2050 groundwater becomes unattainable for 20% of the global population, mainly in the developing countries and pumping cost will increase significantly. Largest impacts are found

  16. Shaping the contours of groundwater governance in India

    OpenAIRE

    Kulkarni, Himanshu; Shah, Mihir; P.S. Vijay Shankar

    2015-01-01

    Study region: India. Study focus: India's groundwater dependence and the crises of depletion and contamination of groundwater resources require the development of a robust groundwater dependence framework. Understanding the challenges of developing a groundwater governance framework for regions of extensive groundwater development versus relatively less-developed areas of groundwater development is important. The groundwater typology is a function of both, the hydrogeological aspects of gr...

  17. Improving the representation of river-groundwater interactions in land surface modeling at the regional scale: Observational evidence and parameterization applied in the Community Land Model

    KAUST Repository

    Zampieri, Matteo

    2012-02-01

    Groundwater is an important component of the hydrological cycle, included in many land surface models to provide a lower boundary condition for soil moisture, which in turn plays a key role in the land-vegetation-atmosphere interactions and the ecosystem dynamics. In regional-scale climate applications land surface models (LSMs) are commonly coupled to atmospheric models to close the surface energy, mass and carbon balance. LSMs in these applications are used to resolve the momentum, heat, water and carbon vertical fluxes, accounting for the effect of vegetation, soil type and other surface parameters, while lack of adequate resolution prevents using them to resolve horizontal sub-grid processes. Specifically, LSMs resolve the large-scale runoff production associated with infiltration excess and sub-grid groundwater convergence, but they neglect the effect from loosing streams to groundwater. Through the analysis of observed data of soil moisture obtained from the Oklahoma Mesoscale Network stations and land surface temperature derived from MODIS we provide evidence that the regional scale soil moisture and surface temperature patterns are affected by the rivers. This is demonstrated on the basis of simulations from a land surface model (i.e., Community Land Model - CLM, version 3.5). We show that the model cannot reproduce the features of the observed soil moisture and temperature spatial patterns that are related to the underlying mechanism of reinfiltration of river water to groundwater. Therefore, we implement a simple parameterization of this process in CLM showing the ability to reproduce the soil moisture and surface temperature spatial variabilities that relate to the river distribution at regional scale. The CLM with this new parameterization is used to evaluate impacts of the improved representation of river-groundwater interactions on the simulated water cycle parameters and the surface energy budget at the regional scale. © 2011 Elsevier B.V.

  18. Groundwater availability of the Mississippi embayment

    Science.gov (United States)

    Clark, Brian R.; Hart, Rheannon M.; Gurdak, Jason J.

    2011-01-01

    Groundwater is an important resource for agricultural and municipal uses in the Mississippi embayment. Arkansas ranks first in the Nation for rice and third for cotton production, with both crops dependent on groundwater as a major source of irrigation requirements. Multiple municipalities rely on the groundwater resources to provide water for industrial and public use, which includes the city of Memphis, Tennessee. The demand for the groundwater resource has resulted in groundwater availability issues in the Mississippi embayment including: (1) declining groundwater levels of 50 feet or more in the Mississippi River Valley alluvial aquifer in parts of eastern Arkansas from agricultural pumping, (2) declining groundwater levels of over 360 feet over the last 90 years in the confined middle Claiborne aquifer in southern Arkansas and northern Louisiana from municipal pumping, and (3) litigation between the State of Mississippi and a Memphis water utility over water rights in the middle Claiborne aquifer. To provide information to stakeholders addressing the groundwater-availability issues, the U.S. Geological Survey Groundwater Resources Program supported a detailed assessment of groundwater availability through the Mississippi Embayment Regional Aquifer Study (MERAS). This assessment included (1) an evaluation of how these resources have changed over time through the use of groundwater budgets, (2) development of a numerical modeling tool to assess system responses to stresses from future human uses and climate trends, and (3) application of statistical tools to evaluate the importance of individual observations within a groundwater-monitoring network. An estimated 12 million acre-feet per year (11 billion gallons per day) of groundwater was pumped in 2005 from aquifers in the Mississippi embayment. Irrigation constitutes the largest groundwater use, accounting for approximately 10 million acre-feet per year (9 billion gallons per day) in 2000 from the Mississippi

  19. Review of Groundwater Protection and Management in China

    Institute of Scientific and Technical Information of China (English)

    LIU Dan; ZHANG Ai-ping

    2008-01-01

    This review begins with an introduction of groundwater resources in China and their distribution characteristic, followed by an elaboration of the exploitation and utilization of groundwater and the negative environmental effects from groundwater overexploitation, and a description of the existing groundwater protection and management measures. At last, the existing problems in groundwater protection and management, with some suggestions, are presented.

  20. Groundwater surface mapping informs sources of catchment baseflow

    OpenAIRE

    J. F. Costelloe; T. J. Peterson; K. Halbert; A. W. Western; J. J. McDonnell

    2014-01-01

    Groundwater discharge is a major contributor to stream baseflow. Quantifying this flux is difficult, despite its considerable importance to water resource management and evaluation of the effects of groundwater extraction on streamflow. It is important to be able to differentiate between contributions to streamflow from regional groundwater discharge (more susceptible to groundwater extraction) compared to interflow processes (arguably less susceptible to groundwater ...

  1. Integrated approach for the assessment and development of groundwater resources in arid lands: Applications in the Quetta Valley, Pakistan

    Science.gov (United States)

    Sagintayev, Zhanay (Jay Sagin)

    The lack of adequate field measurements (e.g., precipitation and stream flow) and difficulty in obtaining them often hampers the construction and calibration of rainfall-runoff models over many of the world's watersheds, leaving key elements of the hydrologic cycle unconstrained. I adopted methodologies that rely heavily on readily available remote sensing datasets as viable alternatives and useful tools for assessing, managing, and modeling the water resources of such remote and inadequately gauged regions. The Soil and Water Assessment Tool was selected for continuous (1998--2005) rainfall-runoff modeling of the northeast part of the Pishin Lora basin (NEPL), a politically unstable area that lacks adequate rain gauge and stream flow data. To account for the paucity of rain gauge and stream flow gauge data, input to the model included satellite-based Tropical Rainfall Measuring Mission TRMM precipitation data. Modeled runoff was calibrated against satellite-based observations including: (1) monthly estimates of the water volumes impounded by the Khushdil Khan (latitude 30° 40'N, longitude 67° 40'E) and the Kara Lora (latitude 30° 34'N, longitude 66° 52'E) reservoirs, and (2) inferred wet versus dry conditions in streams across the NEPL throughout this period. Calibrations were also conducted against observed flow reported from the Burj Aziz Khan station at the NEPL outlet (latitude 30°20'N; longitude 66°35'E). Model simulations indicate that (1) average annual precipitation (1998--2005), surface runoff, and net recharge are 1,300 x 106 m3, 148 x 106 m3, and 361 x 106 m3, respectively; (2) within the NEPL watershed, precipitation and runoff are high for the northeast (precipitation: 194 mm/year; runoff: 38 x 106 m 3/year) and northwest (134 mm/year; 26 x 106 m3/y) basins compared to the southern basin (124 mm/year; 8 x 106 m3/year); and (3) construction of delay action dams in the northeast and northwest basins of the NEPL could increase recharge from 361 x

  2. Valuing groundwater: A practical approach for integrating ...

    African Journals Online (AJOL)

    groundwater economic values into decision making ... The methodology incorporates a 2-tiered valuation approach. .... groundwater systems in Botswana (SADC, 2010). .... tion) can be investigated to support water resource management.

  3. Reconnaissance of ground-water resources in the vicinity of Gunnison and Crested Butte, West-central Colorado

    Science.gov (United States)

    Giles, T.F.

    1980-01-01

    Hydrologic data was collected in the Gunnison-Crested Butte area , Colo., to determine the availability and chemical quality of groundwater. Parts of the area have undergone rapid population growth in recent years due to an increase of winter sports activities. This rapid growth has resulted in a demand for additional domestic, recreational, and municipal water supplies. Maximum yields of 100 gallons per minute are available from wells completed in the alluvial aquifers while as much as 60 gallons per minute may be obtained from wells completed in the Dakota and Entrada Sandstones. Yields from other aquifers generally are less than 25 gallons per minute. Calcium magnesium bicarbonate water is the predominant water type in the study area. Dissolved solids concentrations ranged from 30 to 829 milligrams per liter and hardness ranged from 18 to 400 milligrams per liter. (USGS)

  4. Groundwater depletion embedded in international food trade

    Science.gov (United States)

    Dalin, Carole; Wada, Yoshihide; Kastner, Thomas; Puma, Michael J.

    2017-03-01

    Recent hydrological modelling and Earth observations have located and quantified alarming rates of groundwater depletion worldwide. This depletion is primarily due to water withdrawals for irrigation, but its connection with the main driver of irrigation, global food consumption, has not yet been explored. Here we show that approximately eleven per cent of non-renewable groundwater use for irrigation is embedded in international food trade, of which two-thirds are exported by Pakistan, the USA and India alone. Our quantification of groundwater depletion embedded in the world’s food trade is based on a combination of global, crop-specific estimates of non-renewable groundwater abstraction and international food trade data. A vast majority of the world’s population lives in countries sourcing nearly all their staple crop imports from partners who deplete groundwater to produce these crops, highlighting risks for global food and water security. Some countries, such as the USA, Mexico, Iran and China, are particularly exposed to these risks because they both produce and import food irrigated from rapidly depleting aquifers. Our results could help to improve the sustainability of global food production and groundwater resource management by identifying priority regions and agricultural products at risk as well as the end consumers of these products.

  5. Impacts of an ethanol-blended fuel release on groundwater and fate of produced methane: simulation of field observations

    Science.gov (United States)

    Rasa, Ehsan; Bekins, Barbara A.; Mackay, Douglas M.; de Sieyes, Nicholas R.; Wilson, John T.; Feris, Kevin P.; Wood, Isaac A.; Scow, Kate M.

    2013-01-01

    In a field experiment at Vandenberg Air Force Base (VAFB) designed to mimic the impact of a small-volume release of E10 (10% ethanol and 90% conventional gasoline), two plumes were created by injecting extracted groundwater spiked with benzene, toluene, and o-xylene, abbreviated BToX (No-Ethanol Lane) and BToX plus ethanol (With-Ethanol Lane) for 283 days. We developed a reactive transport model to understand processes controlling the fate of ethanol and BToX. The model was calibrated to the extensive field dataset and accounted for concentrations of sulfate, iron, acetate, and methane along with iron-reducing bacteria, sulfate-reducing bacteria, fermentative bacteria, and methanogenic archaea. The benzene plume was about 4.5 times longer in the With-Ethanol Lane than in the No-Ethanol Lane. Matching this different behavior in the two lanes required inhibiting benzene degradation in the presence of ethanol. Inclusion of iron reduction with negligible growth of iron-reducers was required to reproduce the observed constant degradation rate of benzene. Modeling suggested that vertical dispersion and diffusion of sulfate from an adjacent aquitard were important sources of sulfate in the aquifer. Matching of methane data required incorporating initial fermentation of ethanol to acetate, methane loss by outgassing, and methane oxidation coupled to sulfate and iron reduction. Simulation of microbial growth using dual Monod kinetics, and including inhibition by more favorable electron acceptors, generally resulted in reasonable yields for microbial growth of 0.01-0.05.

  6. Impacts of an ethanol-blended fuel release on groundwater and fate of produced methane: Simulation of field observations

    Science.gov (United States)

    Rasa, Ehsan; Bekins, Barbara A.; Mackay, Douglas M.; Sieyes, Nicholas R.; Wilson, John T.; Feris, Kevin P.; Wood, Isaac A.; Scow, Kate M.

    2013-08-01

    In a field experiment at Vandenberg Air Force Base (VAFB) designed to mimic the impact of a small-volume release of E10 (10% ethanol and 90% conventional gasoline), two plumes were created by injecting extracted groundwater spiked with benzene, toluene, and o-xylene, abbreviated BToX (no-ethanol lane) and BToX plus ethanol (with-ethanol lane) for 283 days. We developed a reactive transport model to understand processes controlling the fate of ethanol and BToX. The model was calibrated to the extensive field data set and accounted for concentrations of sulfate, iron, acetate, and methane along with iron-reducing bacteria, sulfate-reducing bacteria, fermentative bacteria, and methanogenic archaea. The benzene plume was about 4.5 times longer in the with-ethanol lane than in the no-ethanol lane. Matching this different behavior in the two lanes required inhibiting benzene degradation in the presence of ethanol. Inclusion of iron reduction with negligible growth of iron reducers was required to reproduce the observed constant degradation rate of benzene. Modeling suggested that vertical dispersion and diffusion of sulfate from an adjacent aquitard were important sources of sulfate in the aquifer. Matching of methane data required incorporating initial fermentation of ethanol to acetate, methane loss by outgassing, and methane oxidation coupled to sulfate and iron reduction. Simulation of microbial growth using dual Monod kinetics, and including inhibition by more favorable electron acceptors, generally resulted in reasonable yields for microbial growth of 0.01-0.05.

  7. Analyses of infrequent (quasi-decadal) large groundwater recharge events in the northern Great Basin: Their importance for groundwater availability, use, and management

    Science.gov (United States)

    Masbruch, Melissa D.; Rumsey, Christine; Gangopadhyay, Subhrendu; Susong, David D.; Pruitt, Tom

    2016-01-01

    There has been a considerable amount of research linking climatic variability to hydrologic responses in the western United States. Although much effort has been spent to assess and predict changes in surface water resources, little has been done to understand how climatic events and changes affect groundwater resources. This study focuses on characterizing and quantifying the effects of large, multiyear, quasi-decadal groundwater recharge events in the northern Utah portion of the Great Basin for the period 1960–2013. Annual groundwater level data were analyzed with climatic data to characterize climatic conditions and frequency of these large recharge events. Using observed water-level changes and multivariate analysis, five large groundwater recharge events were identified with a frequency of about 11–13 years. These events were generally characterized as having above-average annual precipitation and snow water equivalent and below-average seasonal temperatures, especially during the spring (April through June). Existing groundwater flow models for several basins within the study area were used to quantify changes in groundwater storage from these events. Simulated groundwater storage increases per basin from a single recharge event ranged from about 115 to 205 Mm3. Extrapolating these amounts over the entire northern Great Basin indicates that a single large quasi-decadal recharge event could result in billions of cubic meters of groundwater storage. Understanding the role of these large quasi-decadal recharge events in replenishing aquifers and sustaining water supplies is crucial for long-term groundwater management.

  8. Analyses of infrequent (quasi-decadal) large groundwater recharge events in the northern Great Basin: Their importance for groundwater availability, use, and management

    Science.gov (United States)

    Gangopadhyay, Subhrendu; Masbruch, Melissa D.; Pruitt, Tom; Rumsey, Christine; Susong, David D.

    2016-01-01

    There has been a considerable amount of research linking climatic variability to hydrologic responses in the western United States. Although much effort has been spent to assess and predict changes in surface water resources, little has been done to understand how climatic events and changes affect groundwater resources. This study focuses on characterizing and quantifying the effects of large, multiyear, quasi-decadal groundwater recharge events in the northern Utah portion of the Great Basin for the period 1960–2013. Annual groundwater level data were analyzed with climatic data to characterize climatic conditions and frequency of these large recharge events. Using observed water-level changes and multivariate analysis, five large groundwater recharge events were identified with a frequency of about 11–13 years. These events were generally characterized as having above-average annual precipitation and snow water equivalent and below-average seasonal temperatures, especially during the spring (April through June). Existing groundwater flow models for several basins within the study area were used to quantify changes in groundwater storage from these events. Simulated groundwater storage increases per basin from a single recharge event ranged from about 115 to 205 million cubic meters. Extrapolating these amounts over the entire northern Great Basin indicates that a single large quasi-decadal recharge event could result in billions of cubic meters of groundwater storage. Understanding the role of these large quasi-decadal recharge events in replenishing aquifers and sustaining water supplies is crucial for long-term groundwater management.

  9. Analyses of infrequent (quasi-decadal) large groundwater recharge events in the northern Great Basin: Their importance for groundwater availability, use, and management

    Science.gov (United States)

    Masbruch, Melissa D.; Rumsey, Christine A.; Gangopadhyay, Subhrendu; Susong, David D.; Pruitt, Tom

    2016-10-01

    There has been a considerable amount of research linking climatic variability to hydrologic responses in the western United States. Although much effort has been spent to assess and predict changes in surface water resources, little has been done to understand how climatic events and changes affect groundwater resources. This study focuses on characterizing and quantifying the effects of large, multiyear, quasi-decadal groundwater recharge events in the northern Utah portion of the Great Basin for the period 1960-2013. Annual groundwater level data were analyzed with climatic data to characterize climatic conditions and frequency of these large recharge events. Using observed water-level changes and multivariate analysis, five large groundwater recharge events were identified with a frequency of about 11-13 years. These events were generally characterized as having above-average annual precipitation and snow water equivalent and below-average seasonal temperatures, especially during the spring (April through June). Existing groundwater flow models for several basins within the study area were used to quantify changes in groundwater storage from these events. Simulated groundwater storage increases per basin from a single recharge event ranged from about 115 to 205 Mm3. Extrapolating these amounts over the entire northern Great Basin indicates that a single large quasi-decadal recharge event could result in billions of cubic meters of groundwater storage. Understanding the role of these large quasi-decadal recharge events in replenishing aquifers and sustaining water supplies is crucial for long-term groundwater management.

  10. Groundwater storage changes from GRACE satellite in the Southern Gobi Region of Mongolia

    Science.gov (United States)

    Nemer, B.; Yanping, C.; Bayanzul, B. B.; Altangerel, E. E.

    2014-12-01

    Groundwater is an important resource in the Southern Gobi Region of Mongolia because rainfall and surface water availability are severely limited and the demands are expected to increase rapidly with the development of mining and new population centers. Groundwater systems are more complex and yet its distribution and quantity are poorly known. The purpose of the research is to evaluate the potential utility of GRACE (Gravity Recovery and Climate Experiment) satellites to monitor groundwater storage in the arid area. Regional groundwater storage changes in SGR are estimated using monthly GRACE total water storage change data. Groundwater storage change estimates are compared to groundwater level measurements of 66 shallow dug wells and 72 deep boreholes for the period 2004-2012. Groundwater storage decreases during the cold season and increases during the warm season. Seasonal groundwater change calculated from GRACE total water storage is highly correlated to groundwater level measurements in shallow aquifers. There is no correlation between groundwater storage changes derived from GRACE and deep aquifer. The result indicates that GRACE can be used to monitor large area where groundwater observation is limited, especially unconfined shallow aquifers.

  11. Preliminary hydrogeologic assessment and study plan for a regional ground-water resource investigation of the Blue Ridge and Piedmont provinces of North Carolina

    Science.gov (United States)

    Daniel, Charles C.; Dahlen, Paul R.

    2002-01-01

    Prolonged drought, allocation of surface-water flow, and increased demands on ground-water supplies resulting from population growth are focuses for the need to evaluate ground-water resources in the Blue Ridge and Piedmont Provinces of North Carolina. Urbanization and certain aspects of agricultural production also have caused increased concerns about protecting the quality of ground water in this region. More than 75 percent of the State's population resides in the Blue Ridge and Piedmont Provinces in an area that covers 30,544 square miles and 65 counties. Between 1940 and 2000, the population in the Piedmont and Blue Ridge Provinces increased from 2.66 to 6.11 million; most of this increase occurred in the Piedmont. Of the total population, an estimated 1.97 million people, or 32.3 percent (based on the 1990 census), relied on ground water for a variety of uses, including commercial, industrial, and most importantly, potable supplies. Ground water in the Blue Ridge and Piedmont traditionally has not been considered as a source for large supplies, primarily because of readily available and seemingly limitless surface-water supplies, and the perception that ground water in the Blue Ridge and Piedmont Provinces occurs in a complex, generally heterogeneous geologic environment. Some reluctance to use ground water for large supplies derives from the reputation of aquifers in these provinces for producing low yields to wells, and the few high-yield wells that are drilled seem to be scattered in areas distant from where they are needed. Because the aquifers in these provinces are shallow, they also are susceptible to contamination by activities on the land surface. In response to these issues, the North Carolina Legislature supported the creation of a Resource Evaluation Program to ensure the long-term availability, sustainability, and quality of ground water in the State. As part of the Resource Evaluation Program, the North Carolina Division of Water Quality

  12. Groundwater contamination in Japan

    Energy Technology Data Exchange (ETDEWEB)

    Tase, Norio [Univ. of Tsukuba, Ibaraki (Japan)

    1992-07-01

    Problems on groundwater contamination in Japan are briefly summarized in this paper. Although normal physical conditions in Japan restrict the possibilities of groundwater contamination, human activities are threatening groundwater resources. A survey by the Environment Agency of Japan showed nationwide spreading of organic substances, such as trichloroethylene as well as nitrogen compounds. Synthetic detergents have also been detected even in rural areas and in deep confined aquifers, although their concentrations are not as high. Public awareness of agrichemical or pesticides abuse, especially from golf courses, is apparent. Other problems such as nitrate-nitrogen, leachate from landfills, and the leaking of underground storage tanks are also discussed. 9 refs., 3 figs., 4 tabs.

  13. Groundwater contamination in Japan

    Science.gov (United States)

    Tase, Norio

    1992-07-01

    Problems on groundwater contamination in Japan are briefly summarized in this paper. Although normal physical conditions in Japan restrict the possibilities of groundwater contamination, human activities are threatening groundwater resources. A survey by the Environment Agency of Japan showed nationwide spreading of organic substances, such as trichloroethylene as well as nitrogen compounds. Synthetic detergents have also been detected even in rural areas and in deep confined aquifers, although their concentrations are not as high. Public awareness of agrichemical or pesticides abuse, especially from golf courses, is apparent. Other problems such as nitrate-nitrogen, leachate from landfills, and the leaking of underground storage tanks are also discussed.

  14. California's Central Valley Groundwater Study: A Powerful New Tool to Assess Water Resources in California's Central Valley

    Science.gov (United States)

    Faunt, Claudia C.; Hanson, Randall T.; Belitz, Kenneth; Rogers, Laurel

    2009-01-01

    Competition for water resources is growing throughout California, particularly in the Central Valley. Since 1980, the Central Valley's population has nearly doubled to 3.8 million people. It is expected to increase to 6 million by 2020. Statewide population growth, anticipated reductions in Colorado River water deliveries, drought, and the ecological crisis in the Sacramento-San Joaquin Delta have created an intense demand for water. Tools and information can be used to help manage the Central Valley aquifer system, an important State and national resource.

  15. Regional groundwater flow modeling of the Geba basin, northern Ethiopia

    Science.gov (United States)

    Gebreyohannes, Tesfamichael; De Smedt, Florimond; Walraevens, Kristine; Gebresilassie, Solomon; Hussien, Abdelwassie; Hagos, Miruts; Amare, Kassa; Deckers, Jozef; Gebrehiwot, Kindeya

    2017-01-01

    The Geba basin is one of the most food-insecure areas of the Tigray regional state in northern Ethiopia due to recurrent drought resulting from erratic distribution of rainfall. Since the beginning of the 1990s, rain-fed agriculture has been supported through small-scale irrigation schemes mainly by surface-water harvesting, but success has been limited. Hence, use of groundwater for irrigation purposes has gained considerable attention. The main purpose of this study is to assess groundwater resources in the Geba basin by means of a MODFLOW modeling approach. The model is calibrated using observed groundwater levels, yielding a clear insight into the groundwater flow systems and reserves. Results show that none of the hydrogeological formations can be considered as aquifers that can be exploited for large-scale groundwater exploitation. However, aquitards can be identified that can support small-scale groundwater abstraction for irrigation needs in regions that are either designated as groundwater discharge areas or where groundwater levels are shallow and can be tapped by hand-dug wells or shallow boreholes.

  16. Regional groundwater flow modeling of the Geba basin, northern Ethiopia

    Science.gov (United States)

    Gebreyohannes, Tesfamichael; De Smedt, Florimond; Walraevens, Kristine; Gebresilassie, Solomon; Hussien, Abdelwassie; Hagos, Miruts; Amare, Kassa; Deckers, Jozef; Gebrehiwot, Kindeya

    2017-05-01

    The Geba basin is one of the most food-insecure areas of the Tigray regional state in northern Ethiopia due to recurrent drought resulting from erratic distribution of rainfall. Since the beginning of the 1990s, rain-fed agriculture has been supported through small-scale irrigation schemes mainly by surface-water harvesting, but success has been limited. Hence, use of groundwater for irrigation purposes has gained considerable attention. The main purpose of this study is to assess groundwater resources in the Geba basin by means of a MODFLOW modeling approach. The model is calibrated using observed groundwater levels, yielding a clear insight into the groundwater flow systems and reserves. Results show that none of the hydrogeological formations can be considered as aquifers that can be exploited for large-scale groundwater exploitation. However, aquitards can be identified that can support small-scale groundwater abstraction for irrigation needs in regions that are either designated as groundwater discharge areas or where groundwater levels are shallow and can be tapped by hand-dug wells or shallow boreholes.

  17. Impacts of an ethanol-blended fuel release on groundwater and fate of produced methane: Simulation of field observations

    Science.gov (United States)

    In a field experiment at Vandenberg Air Force Base (VAFB) designed to mimic the impact of a small-volume release of E10, two plumes were created by injecting extracted groundwater spiked with benzene, toluene, and o-xylene, abbreviated BToX (No-Ethanol Lane) and BToX plus ethanol...

  18. Impacts of an ethanol-blended fuel release on groundwater and fate of produced methane: Simulation of field observations

    Science.gov (United States)

    In a field experiment at Vandenberg Air Force Base (VAFB) designed to mimic the impact of a small-volume release of E10, two plumes were created by injecting extracted groundwater spiked with benzene, toluene, and o-xylene, abbreviated BToX (No-Ethanol Lane) and BToX plus ethanol...

  19. Groundwater systems of the Indian Sub-Continent

    Directory of Open Access Journals (Sweden)

    Abhijit Mukherjee

    2015-09-01

    Full Text Available The Indian Sub-Continent is one of the most densely populated regions of the world, hosting ∼23% of the global population within only ∼3% of the world's land area. It encompasses some of the world's largest fluvial systems in the world (River Brahmaputra, Ganges and Indus Basins, which hosts some of the highest yielding aquifers in the world. The distribution of usable groundwater in the region varies considerably and the continued availability of safe water from many of these aquifers (e.g. Bengal Basin is constrained by the presence of natural contaminants. Further, the trans-boundary nature of the aquifers in the Indian Sub-Continent makes groundwater resource a potentially politically sensitive issue, particularly since this region is the largest user of groundwater resources in the world. Indeed, there is considerable concern regarding dwindling well yield and declining groundwater levels, even for the highly productive aquifers. Though irrigation already accounts for >85% of the total ground water extraction of the region, there is a mounting pressure on aquifers for food security of the region. Highly variable precipitation, hydrogeological conditions and predicted, impending climate change effects provide substantial challenges to groundwater management. The observed presence of natural groundwater contaminants together with the growing demand for irrigated food production and predicted climate change further complicate the development of strategies for using groundwater resources sustainably. We provide an introduction and overview of 11 articles, collated in this special issue, which describe the current condition of vulnerable groundwater resources across the Indian Sub-Continent.

  20. Ground-water resources of the South Platte River Basin in western Adams and southwestern Weld Counties, Colorado

    Science.gov (United States)

    Smith, Rex O.; Schneider, P.A.; Petri, Lester R.

    1964-01-01

    ground water for irrigation, municipal, and industrial use are obtained in the principal stream valleys from wells tapping valley-fill deposits beneath the flood plain and bordering terraces. Many domestic and stock wells obtain water from the unconsolidated deposits both on the uplands and in the valleys. The ground water in the valley-fill deposits generally is unconfined but in a few places is under slight artesian pressure. The bedrock formations yield small to moderate supplies of water to municipal, industrial, domestic, and stock wells, but the yields are not sufficient for irrigation. Ground water in the South Platte River valley moves downstream and toward the river and is discharged into the river. The direction of ground-water movement in Beebe Draw and Box Elder Creek valley is nearly parallel to the streams. Beebe Seep, the stream in Beebe Draw, gains water from the groundwater reservoir in some reaches and loses water in others, but Box Elder Creek loses water to the ground-water reservoir throughout its course especially during floods. The shape and slope of the water table are affected chiefly by the permeability of the valley-fill deposits, the location and altitude of the areas of recharge and discharge, and the configuration of the underlying bedrock floor. The depth to water in the South Platte River valley ranges from less than 1 foot beneath the flood plain to as much as 80 feet beneath the terraces. In Beebe Draw the depth to water ranges from less than 1 foot to about 60 feet and in Box Elder Creek valley from about 5 feet to about 40 feet. During the period of record the annual fluctuation of water levels in wells in the area has ranged from 2 to 13 feet. Precipitation within the area and infiltrating water from irrigated tracts, reservoirs, canals, and streams are the principal sources of recharge to the ground-water reservoir; some recharge results from underflow from outside the area. Ground water is discharged by evapotranspiratio

  1. Ground-water resources of the glacial outwash along the White River, Johnson and Morgan counties, Indiana

    Science.gov (United States)

    Bailey, Z.C.; Imbrigiotta, T.E.

    1982-01-01

    An 88-square-mile segment of the White River valley contains an unconfined sand and gravel aquifer ranging-from a featheredge zero, to 120 feet in saturated thickness. Hydraulic conductivity is 340 feet per day, and transmissivity is as much as 35,000 square feet per day. The aquifer, recharged primarily by precipitation, gains same recharge through interbedded till and outwash boundaries and through losing streams. A two-dimensional digital model was used to simulate the steady-state ground-water flow system. Sensitivity analyses tested the reaction of the model to adjustments in hydraulic conductivity, steam bed leakance, and recharge. Simulated pumpage of 20-, 66-, and 122-million gallons per day reduced streamflow by 5, 15, and 30% , respectively. A real drawdown did not exceed 25 feet. Ground water was a calcium bicarbonate type having a median pH of 7.1, a mean alkalinity of 240 milligrams per liter, a mean hardness of 280 milligrams per liter, a mean dissolved oxygen concentration of 2.2 milligrams per liter, a mean redox potential of +347 millivolts, and a mean dissolved-solids concentration of 366 milligrams per liter. Iron and manganese concentrations exceeded National Drinking Water Regulations in 15 and 49% of the analyses, respectively. Temperature and concentration of dissolved organic carbon varied seasonally. Dissolved carbon and manganese varied with seasonally. Dissolved carbon and manganese varied with differing boundary material, till and bedrock. (USGS)

  2. Ground-Water Resource Assessment in the Rio Grande de Manati Alluvial Plain, Rio Arriba Saliente Area, Puerto Rico

    Science.gov (United States)

    Torres-Gonzalez, Sigfredo; Gómez-Gómez, Fernando; Warne, Andrew G.

    2002-01-01

    The alluvial aquifer within a 160-acre area of the Rio Grande de Manati alluvial plain was investigated to evaluate its potential as a water-supply source for the Barrios Rio Arriba Saliente and Pugnado Afuera, municipio of Manati, Puerto Rico. Analysis of well boring samples and the results of electric resistivity surveys indicate that the average thickness of the unconsolidated alluvial deposits in the study area is about 100 to 110 feet. The alluvium is a mixture of sand and gravel, which generally has a porosity of 0.2 to 0.35. Short-duration pump tests in small-diameter piezometers indicate that the alluvial aquifer has a hydraulic conductivity of about 200 feet per day and a transmissivity of about 7,900 feet squared per day. Analyses of water levels in piezometers, combined with stage measurements at a series of surveyed reference points along the Rio Grande de Manati channel, indicate that the water-table gradient in the alluvial aquifer is about 0.001, and that ground-water flow is generally from south to north, in the general direction of river flow. The water-table data indicate that the Rio Grande de Manati is the principal source of ground-water recharge to the alluvial aquifer in the study area. Because base flow for the Rio Grande de Manati is usually greater than 44 cubic feet per second, a continuous withdrawal rate of 0.5 to 1.0 cubic foot per second (225 to 450 gallons per minute) from a production well is possible. Chemical analysis of a ground-water sample indicates that the alluvial aquifer water meets U.S. Environmental Protection Agency secondary standards for selected constituents. Bacteriological analysis of ground-water samples indicates that the ground water contains little or no fecal coliform or fecal streptococcus bacteria. Although long-term data from upstream of the study area indicate high levels of fecal coliform and fecal streptococcus prior to 1996, bacteriological analyses of Rio Grande de Manati water samples obtained during

  3. The Effects of Wheat Guarantee Price on the Economic Value of Groundwater Resources; the Case Study of Orzoiye Region, Kerman

    Directory of Open Access Journals (Sweden)

    S.H. Mosavi

    2016-03-01

    Full Text Available Introduction: Agriculture as one of main axis of development in Iran is heavily depend on irrigation water. on the other hand, water resources have been under heavy pressure due to rising demand with different uses. Hence, water resources management and optimal water allocation have become increasingly important Undoubtedly, one of the most important tools for optimal allocation of water resources, is the economic valuation of the long-term development strategy of the country. However, the main question is whether the various agricultural policies of the government are to achieve self-sufficiency in the production decisions, in line with the management of water resources? Materials and Methods: To develop an analytical context for responding to above question, in this study, the effect of guaranteed purchase policy of wheat as one of the most supporting government policies, on the economic value of water resources in Orzoiyeh plain of Kerman province was studied. In order to achieve our goals, a dynamic mathematical programming model was used. A number of key questions are involved with the modeling of dynamic situations. Fundamentally, one must ask whether an explicit multiple time period representation is necessary. If so, a number of other questions are relevant. First, the length of the total time period and the starting date must be determined. Second, the length of the time intervals explicitly represented within the total time period must be determined. Third, initial and final inventory conditions must be specified. Fourth, one must decide on activity life, i.e., when a particular activity is begun and how long it lasts. Fifth, the rate of time preference must be determined, i.e., one needs the discount rate at which future returns are considered when compared with current returns. Sixth and finally, one must decide whether to include uncertainty. The sections below present discussion on each of these topics. Dynamic situations may not

  4. Multi-Objective Groundwater Quantity Management. A Stochastic Approach

    NARCIS (Netherlands)

    Ndambuki, J.M.

    2001-01-01

    The question of managing groundwater resources is one of implementing institutions that regulate the use of the resource so as to harvest maximum benefits without imparting undesirable consequences on the system. Traditionally, regional groundwater management problems have been solved deterministica

  5. Numerical modeling of geothermal groundwater flow in karst aquifer system in eastern Weibei, Shaanxi Province, China

    Institute of Scientific and Technical Information of China (English)

    LI Ming; LI GuoMin; YANG Liao; DANG XueYa; ZHAO ChunHu; HOU GuangCai; ZHANG MaoSheng

    2007-01-01

    The quantitative assessment of geothermal water resources is important to the exploitation and utilization of geothermal resources. In the geothermal water systems the density of groundwater changes with the temperature, therefore the variations in hydraulic heads and temperatures are very complicated. A three-dimensional density-dependent model coupling the groundwater flow and heat transport is established and used to simulate the geothermal water flow in the karst aquifers in eastern Weibei,Shaanxi Province, China. The multilayered karst aquifer system in the study area is cut by some major faults which control the regional groundwater flow. In order to calibrate and simulate the effect of the major faults, each fault is discretized as a belt of elements with special hydrological parameters in the numerical model. The groundwater dating data are used to be integrated with the groundwater flow pattern and calibrate the model. Simulation results show that the calculated hydraulic heads and temperature fit with the observed data well.

  6. Investigating patterns and controls of groundwater up-welling in a lowland river by combining fibre-optic distributed temperature sensing with observations of vertical head gradients

    Directory of Open Access Journals (Sweden)

    S. Krause

    2012-01-01

    Full Text Available This paper investigates the patterns and controls of aquifer-river exchange in a fast-flowing lowland river by the conjunctive use of streambed temperature anomalies identified with Fibre-optic Distributed Temperature Sensed (FO-DTS and observations of vertical hydraulic gradients (VHG.

    FO-DTS temperature traces along this lowland river reach reveal discrete patterns with "cold spots" indicating groundwater up-welling. In contrast to previous studies using FO-DTS for investigation of groundwater-surface water exchange, the fibre-optic cable in this study was buried in the streambed sediments, ensuring clear signals despite fast flow and high discharges. During the observed summer baseflow period, streambed temperatures in groundwater up-welling locations were found to be up to 1.5 °C lower than ambient streambed temperatures. Due to the high river flows the cold spots were sharp and distinctly localized without measurable impact on downstream surface water temperature.

    VHG patterns along the stream reach were highly variable in space, revealing strong differences even at small scales. VHG patterns alone are indicators of both, structural heterogeneity of the stream bed as well as of the spatial heterogeneity of the groundwater-surface water exchange fluxes and are thus not conclusive in their interpretation. However, in combination with the high spatial resolution DTS data we were able to separate these two influences and clearly identify locations of enhanced exchange, while also obtaining information on the complex small-scale streambed transmissivity patterns responsible for the very discrete exchange patterns.

  7. Science to support the understanding of south Texas surface-water and groundwater resources in a changing landscape

    Science.gov (United States)

    Ockerman, Darwin J.; Garcia, Travis J.; Opsahl, Stephen P.

    2012-01-01

    Against a backdrop of constant cycles of extreme hydrologic conditions ranging from oppressive droughts to life-threatening floods, the water-resource landscape of south Texas is undergoing constant change. Demands on water resources are increasing because of changes related to population growth, energy demands, agricultural practices, and other human-related activities. In south Texas, the Nueces, San Antonio, and Guadalupe River Basins cover approximately 50,000 square miles and include all or part of 45 counties. These stream systems transect the faulted and fractured carbonate rocks of the Edwards aquifer recharge zone and provide the largest sources of recharge to the aquifer. As the streams make their way to the Gulf of Mexico, they provide water for communities and ecosystems in south Texas and deliver water, sediment, and nutrients to the south Texas bays and estuaries.

  8. Ground-water resources and contamination at Kwajalein Island, Republic of the Marshall Islands, 1990-91

    Science.gov (United States)

    Hunt, Charles D.

    1996-01-01

    Kwajalein Island is the largest of the many low, sandy islets that form Kwajalein Atoll in the western North Pacific Ocean. Salinity and water-level surveys at exploratory monitoring wells in 1990 and 1991 delineated a freshwater lens nearly 40 feet thick floating on saltwater within the carbonate sand and gravel aquifer. A transition zone of mixture between the freshwater and saltwater is as thick as 90 feet. Maximum water-table height is only 1.5 feet above sea level. The freshwater lens thinned and thickened by 5 feet during the year-long field study in response to seasonal rainfall and pumping. Freshwater is produced by airstrip rain catchments and shallow, horizontal wells up to 1,400 feet long. Catchment and ground-water yields are roughly equal on average, but catchment is the principal source during the wet season, whereas the dry season requires sustained pumping. The salinity of pumped water has remained below drinking-water standards since wells were installed in 1971, except during the drought of 1983-84, the most severe drought in the rainfall record dating back to 1945. Wet-season rains at the end of the drought reduced salinity to low levels in just a few months. The operating history of the combined catchment/well water supply indicates that it is capable of producing at least 300,000 gallons per day in all but the driest years, and more in wet years. Several sites are contaminated by fuels, solvents, or metals, but most are at the periphery of the freshwater flow system where contaminants are carried toward the shore. However, three interior sites have greater potential to contaminate nearby water-supply wells.

  9. 关于河北平原区深层地下水资源属性的探讨%Discussions on the property of deep-lying groundwater resources in Hebei Plain

    Institute of Scientific and Technical Information of China (English)

    王欣宝; 张树刚; 谷明旭; 李玉龙

    2012-01-01

    以河北平原为例,采用同位素、地下水资源评价和地下水水位动态3种思路分析了深层地下水资源属性。根据实测地面沉降量反求深层地下水储存资源量的构成,确定了在以往的深层地下水资源计算时储存资源量少计算了32.77%,弹性释放系数比以往的数据大;根据深层地下水动态特征,分析认为深层地下水资源在同一水文年内可以得到部分恢复,在深层地下水降落漏斗区地下水循环速率将加大,并根据沉积学的观点,认为河北平原含水层在各期古河道带交叉重叠部位或在重叠部位附近可能是连通的,浅层地下水可以沿着各期古河道带沉积的砂性土构成的含水层向下补给深层地下水,其补给量远大于通过巨厚的黏性土层向深层地下水的越流补给。%Taking Hebei Plain as an example,the authors adopt isotope geology,groundwater resources evaluation and groundwater level dynamic method to analyze the property of deep-lying groundwater resources.The constitution of deep-lying groundwater exploitation is derived on the basis of the measured land subsidence data.It is determined that the previously calculated storage resource is 32.77% underestimated,and the data of elastic release coefficient at present is larger than the original data.According to the dynamic characteristics of deep-lying groundwater,it is proposed that the deep groundwater resources in the same hydrological year can be partially restored.In deep-lying groundwater funnel area,the groundwater circulation rate will increase,and according to the view point of sedimentology,the aquifer of the overlapping part of the ancient river and its vicinity is probably run-through.Shallow groundwater could pass downward along the aquifer of the ancient river sedimentary sand beds to recharge the deep-lying groundwater,and the amount of supply may be much greater than those recharges passing through the thick clay layer to the deep

  10. Reliable groundwater levels: failures and lessons learned from modeling and monitoring studies

    Science.gov (United States)

    Van Lanen, Henny A. J.

    2017-04-01

    Adequate management of groundwater resources requires an a priori assessment of impacts of intended groundwater abstractions. Usually, groundwater flow modeling is used to simulate the influence of the planned abstraction on groundwater levels. Model performance is tested by using observed groundwater levels. Where a multi-aquifer system occurs, groundwater levels in the different aquifers have to be monitored through observation wells with filters at different depths, i.e. above the impermeable clay layer (phreatic water level) and beneath (artesian aquifer level). A reliable artesian level can only be measured if the space between the outer wall of the borehole (vertical narrow shaft) and the observation well is refilled with impermeable material at the correct depth (post-drilling phase) to prevent a vertical hydraulic connection between the artesian and phreatic aquifer. We were involved in improper refilling, which led to impossibility to monitor reliable artesian aquifer levels. At the location of the artesian observation well, a freely overflowing spring was seen, which implied water leakage from the artesian aquifer affected the artesian groundwater level. Careful checking of the monitoring sites in a study area is a prerequisite to use observations for model performance assessment. After model testing the groundwater model is forced with proposed groundwater abstractions (sites, extraction rates). The abstracted groundwater volume is compensated by a reduction of groundwater flow to the drainage network and the model simulates associated groundwater tables. The drawdown of groundwater level is calculated by comparing the simulated groundwater level with and without groundwater abstraction. In lowland areas, such as vast areas of the Netherlands, the groundwater model has to consider a variable drainage network, which means that small streams only carry water during the wet winter season, and run dry during the summer. The main streams drain groundwater

  11. Understanding similarity of groundwater systems with empirical copulas

    Science.gov (United States)

    Haaf, Ezra; Kumar, Rohini; Samaniego, Luis; Barthel, Roland

    2016-04-01

    Within the classification framework for groundwater systems that aims for identifying similarity of hydrogeological systems and transferring information from a well-observed to an ungauged system (Haaf and Barthel, 2015; Haaf and Barthel, 2016), we propose a copula-based method for describing groundwater-systems similarity. Copulas are an emerging method in hydrological sciences that make it possible to model the dependence structure of two groundwater level time series, independently of the effects of their marginal distributions. This study is based on Samaniego et al. (2010), which described an approach calculating dissimilarity measures from bivariate empirical copula densities of streamflow time series. Subsequently, streamflow is predicted in ungauged basins by transferring properties from similar catchments. The proposed approach is innovative because copula-based similarity has not yet been applied to groundwater systems. Here we estimate the pairwise dependence structure of 600 wells in Southern Germany using 10 years of weekly groundwater level observations. Based on these empirical copulas, dissimilarity measures are estimated, such as the copula's lower- and upper corner cumulated probability, copula-based Spearman's rank correlation - as proposed by Samaniego et al. (2010). For the characterization of groundwater systems, copula-based metrics are compared with dissimilarities obtained from precipitation signals corresponding to the presumed area of influence of each groundwater well. This promising approach provides a new tool for advancing similarity-based classification of groundwater system dynamics. Haaf, E., Barthel, R., 2015. Methods for assessing hydrogeological similarity and for classification of groundwater systems on the regional scale, EGU General Assembly 2015, Vienna, Austria. Haaf, E., Barthel, R., 2016. An approach for classification of hydrogeological systems at the regional scale based on groundwater hydrographs EGU General Assembly

  12. GEOCAB Portal: A gateway for discovering and accessing capacity building resources in Earth Observation

    Science.gov (United States)

    Desconnets, Jean-Christophe; Giuliani, Gregory; Guigoz, Yaniss; Lacroix, Pierre; Mlisa, Andiswa; Noort, Mark; Ray, Nicolas; Searby, Nancy D.

    2017-02-01

    The discovery of and access to capacity building resources are often essential to conduct environmental projects based on Earth Observation (EO) resources, whether they are Earth Observation products, methodological tools, techniques, organizations that impart training in these techniques or even projects that have shown practical achievements. Recognizing this opportunity and need, the European Commission through two FP7 projects jointly with the Group on Earth Observations (GEO) teamed up with the Committee on Earth observation Satellites (CEOS). The Global Earth Observation CApacity Building (GEOCAB) portal aims at compiling all current capacity building efforts on the use of EO data for societal benefits into an easily updateable and user-friendly portal. GEOCAB offers a faceted search to improve user discovery experience with a fully interactive world map with all inventoried projects and activities. This paper focuses on the conceptual framework used to implement the underlying platform. An ISO19115 metadata model associated with a terminological repository are the core elements that provide a semantic search application and an interoperable discovery service. The organization and the contribution of different user communities to ensure the management and the update of the content of GEOCAB are addressed.

  13. Locations, values, and uncertainties of hydraulic-head observations for the transient ground-water flow model, Death Valley regional ground-water flow system, Nevada and California

    Data.gov (United States)

    U.S. Geological Survey, Department of the Interior — This digital geospatial data set contains the locations, values, and uncertainties of hydraulic-head observations used in the calibration of the transient model of...

  14. Locations, values, and uncertainties of hydraulic-head observations for the transient ground-water flow model, Death Valley regional ground-water flow system, Nevada and California

    Data.gov (United States)

    U.S. Geological Survey, Department of the Interior — This digital geospatial data set contains the locations, values, and uncertainties of hydraulic-head observations used in the calibration of the transient model of...

  15. Soil moisture data as a constraint for groundwater recharge estimation

    Science.gov (United States)

    Mathias, Simon A.; Sorensen, James P. R.; Butler, Adrian P.

    2017-09-01

    Estimating groundwater recharge rates is important for water resource management studies. Modeling approaches to forecast groundwater recharge typically require observed historic data to assist calibration. It is generally not possible to observe groundwater recharge rates directly. Therefore, in the past, much effort has been invested to record soil moisture content (SMC) data, which can be used in a water balance calculation to estimate groundwater recharge. In this context, SMC data is measured at different depths and then typically integrated with respect to depth to obtain a single set of aggregated SMC values, which are used as an estimate of the total water stored within a given soil profile. This article seeks to investigate the value of such aggregated SMC data for conditioning groundwater recharge models in this respect. A simple modeling approach is adopted, which utilizes an emulation of Richards' equation in conjunction with a soil texture pedotransfer function. The only unknown parameters are soil texture. Monte Carlo simulation is performed for four different SMC monitoring sites. The model is used to estimate both aggregated SMC and groundwater recharge. The impact of conditioning the model to the aggregated SMC data is then explored in terms of its ability to reduce the uncertainty associated with recharge estimation. Whilst uncertainty in soil texture can lead to significant uncertainty in groundwater recharge estimation, it is found that aggregated SMC is virtually insensitive to soil texture.

  16. Reconnaissance of ground-water quality in the Papio-Missouri River Natural Resources District, eastern Nebraska, July through September 1992

    Science.gov (United States)

    Verstraeten, Ingrid M.; Ellis, M.J.

    1995-01-01

    A reconnaissance of ground-water quality was conducted in the Papio-Missouri River Natural Resources District of eastern Nebraska. Sixty-one irrigation, municipal, domestic, and industrial wells completed in the principal aquifers--the unconfined Elkhorn, Missouri, and Platte River Valley alluvial aquifers, the upland area alluvial aquifers, and the Dakota aquifer--were selected for water-quality sampling during July, August, and September 1992. Analyses of water samples from the wells included determination of dissolved nitrate as nitrogen and triazine and acetanilide herbicides. Waterquality analyses of a subset of 42 water samples included dissolved solids, major ions, metals, trace elements, and radionuclides. Concentrations of dissolved nitrate as nitrogen in water samples from 2 of 13 wells completed in the upland area alluvial aquifers exceeded the U.S. Environmental Protection Agency Maximum Contaminant Level for drinking water of 10 milligrams per liter. Thirty-nine percent of the dissolved nitrate-as-nitrogen concentrations were less than the detection level of 0.05 milligram per liter. The largest median dissolved nitrate-as-nitrogen concentrations were in water from the upland area alluvial aquifers and the Dakota aquifer. Water from all principal aquifers, except the Dakota aquifer, had detectable concentrations of herbicides. Herbicides detected included alachlor (1 detection), atrazine (13 detections), cyanazine (5 detections), deisopropylatrazine (6 detections), deethylatrazine (9 detections), metolachlor (6 detections), metribuzin (1 detection), prometon (6 detections), and simazine (2 detections). Herbicide concentrations did not exceed U.S. Environmental Protection Agency Maximum Contaminant Levels for drinking water. In areas where the hydraulic gradient favors loss of surface water to ground water, the detection of herbicides in water from wells along the banks of the Platte River indicates that the river could act as a line source of

  17. The challenges facing sustainable and adaptive groundwater ...

    African Journals Online (AJOL)

    The challenges facing sustainable and adaptive groundwater management ... provide the capacity to assure effective and sustainable resource regulation and allocation. ... of alternative strategies needed to achieve sustainable management.

  18. Application of Time-Series Model to Predict Groundwater Dynamic in Sanjiang Plain,Northeast China

    Institute of Scientific and Technical Information of China (English)

    LUAN Zhaoqing; LIU Guihua; YAN Baixing

    2011-01-01

    To study the groundwater dynamic in the typical region of Sanjiang Plain,long-term groundwater level observation data in the Honghe State Farm were collected and analyzed in this paper.The seasonal and long-term groundwater dynamic was explored.From 1996 to 2008,groundwater level kept declining due to intensive exploitation of groundwater resources for rice irrigation.A decline of nearly 5 m was found for almost all the monitoring wells.A time-series method was established to model the groundwater dynamic.Modeled results by time-series model showed that the groundwater level in this region would keep declining according to the current exploitation intensity.A total dropdown of 1.07 m would occur from 2009 to 2012.Time-series model can be used to model and forecast the groundwater dynamic with high accuracy.Measures including control on groundwater exploitation amount and application of water saving irrigation technique should be taken to prevent the continuing declining of groundwater in the Sanjiang Plain.

  19. TYPES OF TOURISM ASSOCIATED WITH GROUND-WATER RESOURCES IN THE ADJOINING COUNTIES OF SATU MARE AND SZABOLCS-SZATMÁR-BEREG

    Directory of Open Access Journals (Sweden)

    BÂTEA (BOTA CĂTĂLINA MARIA

    2015-03-01

    Full Text Available Bearing a long and unceasing history based on harnessing the healing effects of thermal and mineral springs, curative tourism represents one of the earliest forms of travel. Due to its multiple facets of medical, social and economic nature, this form has been aligned on a global upward trend, marking thus a shift towards health tourism. At present, the spectrum of health tourism comprises both the medical and wellness dimensions reuniting several specific types (surgical, therapeutic, medical wellness, leisure and holistic, however the practice of such activities strongly depends on the destination components (natural assets, general and tourism infrastructure. In the case of Satu Mare and Szabolcs-Szatmár-Bereg counties, spas and localities endowed with therapeutic factors (mineral and thermal springs completed with the bioclimatic component tardily undertake this trend in an attempt to reorganise their touristic offer. Within this context, the present paper aims to explore the prespectives for health tourism development through ground-water resources by emphasising the touristic potential of thermal and mineral springs from the two neighbouring counties. Furthermore, the study has revealed that therapeutic and wellness tourism represent viable directions to generate revenue and revitalise the economy of the area.

  20. Evolution of the groundwater system under the impacts of human activities in middle reaches of Heihe River Basin (Northwest China) from 1985 to 2013

    Science.gov (United States)

    Mi, Lina; Xiao, Honglang; Zhang, Jianming; Yin, Zhenliang; Shen, Yongping

    2016-06-01

    Investigation of the evolution of the groundwater system and its mechanisms is critical to the sustainable management of water in river basins. Temporal and spatial distributions and characteristics of groundwater have undergone a tremendous change with the intensity of human activities in the middle reaches of the Heihe River Basin (HRB), the second largest arid inland river basin in northwestern China. Based on groundwater observation data, hydrogeological data, meteorological data and irrigation statistical data, combined with geostatistical analyses and groundwater storage estimation, the basin-scaled evolution of the groundwater levels and storage (from 1985 to 2013) were investigated. The results showed that the unbalanced allocation of water sources and expanded cropland by policy-based human activities resulted in the over-abstraction of groundwater, which induced a general decrease in the water table and groundwater storage. The groundwater level has generally fallen from 4.92 to 11.49 m from 1985 to 2013, especially in the upper and middle parts of the alluvial fan (zone I), and reached a maximum depth of 17.41 m. The total groundwater storage decreased by 177.52 × 108 m3; zone I accounted for about 94.7 % of the total decrease. The groundwater balance was disrupted and the groundwater system was in a severe negative balance; it was noted that the groundwater/surface-water interaction was also deeply affected. It is essential to develop a rational plan for integration and management of surface water and groundwater resources in the HRB.

  1. Response of groundwater level and surface-water/groundwater interaction to climate variability: Clarence-Moreton Basin, Australia

    Science.gov (United States)

    Cui, Tao; Raiber, Matthias; Pagendam, Dan; Gilfedder, Mat; Rassam, David

    2017-08-01

    Understanding the response of groundwater levels in alluvial and sedimentary basin aquifers to climatic variability and human water-resource developments is a key step in many hydrogeological investigations. This study presents an analysis of groundwater response to climate variability from 2000 to 2012 in the Queensland part of the sedimentary Clarence-Moreton Basin, Australia. It contributes to the baseline hydrogeological understanding by identifying the primary groundwater flow pattern, water-level response to climate extremes, and the resulting dynamics of surface-water/groundwater interaction. Groundwater-level measurements from thousands of bores over several decades were analysed using Kriging and nonparametric trend analysis, together with a newly developed three-dimensional geological model. Groundwater-level contours suggest that groundwater flow in the shallow aquifers shows local variations in the close vicinity of streams, notwithstanding general conformance with topographic relief. The trend analysis reveals that climate variability can be quickly reflected in the shallow aquifers of the Clarence-Moreton Basin although the alluvial aquifers have a quicker rainfall response than the sedimentary bedrock formations. The Lockyer Valley alluvium represents the most sensitively responding alluvium in the area, with the highest declining (-0.7 m/year) and ascending (2.1 m/year) Sen's slope rates during and after the drought period, respectively. Different surface-water/groundwater interaction characteristics were observed in different catchments by studying groundwater-level fluctuations along hydrogeologic cross-sections. The findings of this study lay a foundation for future water-resource management in the study area.

  2. Groundwater and geothermal: urban district heating applications

    Energy Technology Data Exchange (ETDEWEB)

    Mounts, R.; Frazier, A.; Wood, E.; Pyles, O.

    1982-01-01

    This report describes how several cities use groundwater and geothermal energy in district heating systems. It begins with groundwater, introducing the basic technology and techniques of development, and describing two case studies of cities with groundwater-based district heating systems. The second half of the report consists of three case studies of cities with district heating systems using higher temperature geothermal resources.

  3. Water resources data for Texas, water year 1997. Volume 4. Ground-water data. Water-data report (Annual), 1 October 1996-30 September 1997

    Energy Technology Data Exchange (ETDEWEB)

    Gandara, S.C.; Jones, R.E.; Barbie, D.L.

    1997-12-03

    Water-resources data for the 1997 water year for Texas consists of records of stage, discharge, and water quality of streams; stage and contents in lakes and reservoirs; and water levels and water quality in wells. Volume 4 contains water levels for 790 observation wells and 245 water-quality data for monitoring wells.

  4. Water resources data for Texas, water year 1996. Volume 4. Ground-water data. Water-data report (Annual), 1 October 1995-30 September 1996

    Energy Technology Data Exchange (ETDEWEB)

    Gandara, S.C.; Jones, R.E.; Barbie, D.L.

    1996-11-22

    Water-resources data for the 1996 water year for Texas consists of records of stage, discharge, and water quality of streams; stage and contents in lakes and reservoirs; and water levels and water quality in wells. Volume 4 contains water levels for 845 observation wells and 187 water-quality data for monitoring wells.

  5. The role of the Spanish Committee of the International Association of Hydrogeologists in the management and protection of Spain's groundwater resources

    Science.gov (United States)

    Custodio, Emilio; Llamas, M.-Ramón; Villarroya, Fermín

    Spain is a relatively large European country (ca. 500,000km2) with extensive semiarid areas in which there exists a large number of good aquifers. In some areas, these aquifers are intensively developed and are the most important sources of fresh water. Nevertheless, groundwater development and protection has rarely been duly considered by the Spanish Water Administration, despite the pressure to remedy this situation by various groups of experts, some of them members of the Water Administration. The Spanish Committee of the International Association of Hydrogeologists (IAH) has been very active during the last decade in promoting activities to spread groundwater science, technology, and management in Spain and outside, mostly in Latin America, and in trying to orient water policy toward issues of groundwater. These activities include mainly the organization of technical and scientific meetings on current topics such as groundwater in the new Water Act, overexploitation, groundwater in water-resources planning, groundwater pollution, natural-recharge estimation and others. The impact of these activities on the recent water policy of Spain seems significant, and the experience gained may be applicable to other countries. Résumé L'Espagne est un pays européen assez étendu (500,000km2 environ), où existent des zones semi-arides possédant de nombreux aquifères intéressants. Dans certaines régions, ces aquifères sont intensivement exploités et constituent les sources essentielles d'eau douce. Cependant, l'exploitation et la protection des eaux souterraines ont rarement été prises en compte de façon correcte par l'Administration Espagnole de l'Eau, malgré les pressions exercées pour remédier à la situation par différents groupes d'experts, dont certains sont membres de l'Administration de l'Eau. Le Comité Espagnol de l'Association Internationale des Hydrogéologues (AIH) a été particulièrement actif au cours de ces dix dernières années pour

  6. 亚洲地下水资源与环境地质系列图及GIS系统结构%Groundwater Resources and Environmental Geology Serial Maps of Asia and the GIS System Structure

    Institute of Scientific and Technical Information of China (English)

    董华; 张健康; 程彦培; 倪增石; 张发旺; 黄志兴; 田廷山; 赵继昌; 高昀; 刘坤

    2011-01-01

    “亚洲地下水资源及环境地质系列图件”(1∶800万)属于洲际尺度图件,包括亚洲水文地质图、亚洲地下水资源图、亚洲地热图和亚洲地下水环境背景图等.针对全球变化,能源危机、资源短缺、环境恶化地质灾害频发的状况,特别是水资源安全保障与地质环境优劣更是直接影响亚洲地区可持续发展,编制上述图件,意义十分重大.亚洲地下水资源及环境地质系列图件,是在亚洲地下水资源及环境地质综合研究基础上,全面分析了国际国内近年来地下水资源与环境地质方面的编图模式,用编制系列图的系统理念,研究制订适合亚洲特点的编图内容及编图方法.应用GIS信息平台,构建亚洲地下水资源与环境GIS系统结构下的数据库,以反映亚洲地下水资源及环境地质时空特征分布规律,为亚洲各国和跨国的自然资源开发利用,水资源规划和地质环境保护防灾减灾,提供科学依据.%"Serial maps of groundwater resource and environmental geology of Asia"(at scale of 1∶8 000 000), including Hydrogeological Map of Asia, Groundwater Resources Map of Asia, Geothermal Map of Asia and Groundwater Environment Background Map of Asia, has been completed based on the research of groundwater resource and environmental geology and overall analysis of mapping pattern of groundwater resource and environmental geology in recent years at home and abroad. The compilation of series maps is of great significance at present for issues over global climate change, energy crisis, resource shortage and environment deterioration and frequent geological hazards we are facing, especially under the condition that water resource safe guarantee and geological environment directly affect the sustainable development in Asia. The mapping content and method suitable for Asia has been developed in consideration of systematical concept of compiling serial maps. The serial maps reflect spatio

  7. Groundwater Resources Evolution and Agricultural Ecological Security in Jinghui Canal Irrigation Area%泾惠渠灌区地下水资源演变与农田生态安全

    Institute of Scientific and Technical Information of China (English)

    刘燕; 张盼盼; 王建莹; 郭曼

    2014-01-01

    通过对泾惠渠灌区地下水形成机理及其演变态势的分析,认为气候条件变化、地质条件变化以及人类活动的负面影响是导致灌区地下水资源量衰减的主要原因,其中人类活动(地表水引水灌溉、地下水开采等)的影响作用最为突出。同时也指出了灌区水资源衰减所引发的农田生态安全问题,地下水资源的衰减已经影响到灌区的可持续发展。从灌溉水量的大小、时间分配以及地下水开采量几个方面讨论了灌区水资源调控方式,指出只有合理联合使用地表水和地下水、涵养地下水源,才能实现灌区水资源的可持续开发利用,确保灌区农业供水安全,维护灌区农田生态环境良性循环。%Based on the recharge mechanism and development trends of the groundwater in Jinghui Canal irrigation area,it was pointed out that cli-mate changes,geological condition changes and the negative impacts of human activities had caused the reduction of groundwater resources,espe-cially irrigation diversion and groundwater exploitation. In the meantime,it also pointed out the agricultural ecological security problems caused by groundwater resources reduction,which had threatened the sustainable development of irrigation area. Aimed at these issues,measures to adjust and control water resources were discussed which included irrigation water quantity,distribution of irrigation time and groundwater exploitation. Fi-nally,it pointed out that the combination use of surface water and groundwater were the effective way to realize the sustainability of groundwater re-sources,water supply safety and thus keeping the virtuous cycle of agricultural eco-environment in Jinghui Canal irrigation area.

  8. Installation of groundwater observation tubes OL-PVP36-38 and drilling of shallow drillholes OL-PP70-71 at Olkiluoto in Eurajoki 2011

    Energy Technology Data Exchange (ETDEWEB)

    Toropainen, V. [Suomen Malmi Oy, Espoo (Finland)

    2012-05-15

    In order to widen the groundwater monitoring network at Olkiluoto, Posiva Oy contracted Suomen Malmi Oy (Smoy) to install new groundwater observation tubes to three locations and to drill two shallow drillholes with standpipes. The identification numbers of the groundwater observation tubes are OL-PVP36, OL-PVP37A, 37B, 37C, OL-PVP38A, 38B, 38C and 38D, and the shallow drillholes are named OL-PP70 and OL-PP71. The observation tubes were installed and the shallow holes drilled between September 22nd and October 12th in 2011. The drilling rig used in the installation work was a GM-200 rig. Drilling equipment consisted of casing tubes (90/77 mm) with drilling bit, 55 mm geo rods and 64 mm drilling bits and T76-equipment for drilling the shallow holes. Monitoring pipes (PVC, 60/52 mm) were lowered into the holes inside the casings. The monitoring pipes consist of a lower section of riser pipe, a middle section of screen pipe and an upper section of riser pipe. The screen pipe slot size is 0.3 mm and the length of the screen section is two metres. Protective stainless steel covers with lock-up caps were installed around the monitoring tubes and the shallow drillholes. In addition to the installation of the tubes, the work included water level measurements after installation. The core samples of the shallow drillholes were logged and reported by geologist. Geological logging included the following parameters: lithology, foliation, fracture parameters, fractured zones, core loss, weathering, fracture frequency, RQD and rock quality. (orig.)

  9. Summary and statistical analysis of precipitation and groundwater data for Brunswick County, North Carolina, Water Year 2008

    Science.gov (United States)

    McSwain, Kristen Bukowski; Strickland, A.G.

    2010-01-01

    Groundwater conditions in Brunswick County, North Carolina, have been monitored continuously since 2000 through the operation and maintenance of groundwater-level observation wells in the surficial, Castle Hayne, and Peedee aquifers of the North Atlantic Coastal Plain aquifer system. Groundwater-resource conditions for the Brunswick County area were evaluated by relating the normal range (25th to 75th percentile) monthly mean groundwater-level and precipitation data for water years 2001 to 2008 to median monthly mean groundwater levels and monthly sum of daily precipitation for water year 2008. Summaries of precipitation and groundwater conditions for the Brunswick County area and hydrographs and statistics of continuous groundwater levels collected during the 2008 water year are presented in this report. Groundwater levels varied by aquifer and geographic location within Brunswick County, but were influenced by drought conditions and groundwater withdrawals. Water levels were normal in two of the eight observation wells and below normal in the remaining six wells. Seasonal Kendall trend analysis performed on more than 9 years of monthly mean groundwater-level data collected in an observation well located within the Brunswick County well field indicated there is a strong downward trend, with water levels declining at a rate of about 2.2 feet per year.

  10. Hydrogeology and ground-water resources of Kahlap Island, Mwoakilloa Atoll, State of Pohnpei, Federated States of Micronesia

    Science.gov (United States)

    Anthony, S.S.

    1996-01-01

    The lens of fresh ground water on Kahlap Island contains about 21.3 million gallons of potable water. Recharge to the freshwater lens is estimated to be 125,000 gallons per day on the basis of a mean annual rainfall of 120 inches. The long-term average sustainable yield is estimated to be about 17,300 gallons per day. The estimated demand for water is about 13,500 gallons per day. Shallow-vertical-tube wells or horizontal- infiltration wells could be used to develop the freshwater lens. The effect of development on the lens can be determined by monitoring the chloride concentration of water from a network of shallow- water-table and deep driven wells. The ground- water resource on Kahlap can be used in conjunc- tion with individual rainwater-catchment systems: rainwater can be used for drinking and cooking, and ground water can be used for sanitary uses. When rainwater-catchment systems fail during extended dry periods, ground water would be available to meet the total demand.

  11. Water resources management in the Ganges Basin: a comparison of three strategies for conjunctive use of groundwater and surface water

    Science.gov (United States)

    Khan, Mahfuzur R.; Voss, Clifford I.; Yu, Winston; Michael, Holly A.

    2014-01-01

    The most difficult water resources management challenge in the Ganges Basin is the imbalance between water demand and seasonal availability. More than 80 % of the annual flow in the Ganges River occurs during the 4-month monsoon, resulting in widespread flooding. During the rest of the year, irrigation, navigation, and ecosystems suffer because of water scarcity. Storage of monsoonal flow for utilization during the dry season is one approach to mitigating these problems. Three conjunctive use management strategies involving subsurface water storage are evaluated in this study: Ganges Water Machine (GWM), Pumping Along Canals (PAC), and Distributed Pumping and Recharge (DPR). Numerical models are used to determine the efficacy of these strategies. Results for the Indian State of Uttar Pradesh (UP) indicate that these strategies create seasonal subsurface storage from 6 to 37 % of the yearly average monsoonal flow in the Ganges exiting UP over the considered range of conditions. This has clear implications for flood reduction, and each strategy has the potential to provide irrigation water and to reduce soil waterlogging. However, GWM and PAC require significant public investment in infrastructure and management, as well as major shifts in existing water use practices; these also involve spatially-concentrated pumping, which may induce land subsidence. DPR also requires investment and management, but the distributed pumping is less costly and can be more easily implemented via adaptation of existing water use practices in the basin.

  12. Evaluation of the Water Quality Pollution Indices for Groundwater Resources of Ghahavand Plain, Hamadan Province, Western Iran

    Directory of Open Access Journals (Sweden)

    Soheil Sobhanardakani

    2016-04-01

    Full Text Available Background: Due to the increasing pollution of water resources, this study was carried out for evaluation of water quality pollution indices for monitoring of heavy metals (As, Zn, Pb and Cu contamination in Ghahavand Plain, Hamadan Province, Western Iran during spring and summer 2012. Methods: Totally, 20 ground water wells were chosen randomly. The samples were filtered (0.45 μm and maintained cool in polyethylene bottles. Samples were taken for the analysis of metals, the former was acidified with HNO3 to pH lower than 2. Metal concentrations were determined using ICP-OES. Results: The mean values of Contamination index (Cd, Heavy metal pollution index (HPI and Heavy metal evaluation index (HEI in samples for spring season were -2.27, 9.01 and 1.73 respectively and in samples for summer season were -1.95, 8.69 and 2.04 respectively. It indicates low contamination levels. Comparing the mean concentrations of the evaluated metals with WHO permissible limits showed a significant difference (P<0.05. Conclusion: The mean concentrations of the metals were significantly lower than the permissible limits. Although the heavy metal pollution of the ground water in Ghahavand Plain is lower than WHO permissible limits, but severe precautions consideration such as manage the use of agricultural inputs, prevention of use of wastewater and sewage sludge in agriculture, control of overuse of organic fertilizers and establishment of pollutant industries are recommended in this area.

  13. Geologic influence on groundwater salinity drives large seawater circulation through the continental shelf

    Science.gov (United States)

    Michael, Holly A.; Scott, Kaileigh C.; Koneshloo, Mohammad; Yu, Xuan; Khan, Mahfuzur R.; Li, Katie

    2016-10-01

    Observations of offshore freshened groundwater and saline groundwater discharge along continental shelves have important implications for water resources, ecosystem function, and the composition of the ocean, but they cannot be explained by basic theory. We show that these independent observations are linked and result from processes that drive variable-density groundwater flow through the spatial heterogeneity that is ubiquitous in geologic formations. We use lithologic data to develop geostatistical models that mimic the architecture of coastal aquifers. Simulation of groundwater flow and salt transport through these random realizations shows that heterogeneity produces spatially complex subsurface salinity distributions that extend tens of kilometers offshore, even at steady state. The associated density gradients drive high saline groundwater circulation rates that cannot be predicted by equivalent homogeneous models. Results suggest that these phenomena may be common along continental shelves, potentially altering estimates of ocean chemical budgets and impacting coastal water management for future generations.

  14. Groundwater withdrawal rates from the Ozark Plateaus aquifer system, 1900 to 2010

    Science.gov (United States)

    Knierim, Katherine J.; Nottmeier, Anna M.; Worland, Scott C.; Westerman, Drew A.; Clark, Brian R.

    2016-01-01

    Groundwater is an often overlooked freshwater resource compared to surface water, but groundwater is used widely across the United States, especially during periods of drought. If groundwater models can successfully simulate past conditions, they may be used to evaluate potential future pumping scenarios or climate conditions, thus providing a valuable planning tool for water-resource managers. Quantifying the groundwater-use component for a groundwater model is a vital but often challenging endeavor. This dataset includes groundwater withdrawal rates modeled for the Ozark Plateaus aquifer system (Ozark system) from 1900 to 2010 by groundwater model cell (2.6 square kilometers) for five water-use divisions—agriculture (including irrigation and aquaculture), livestock, public supply (including municipal and rural water districts), and non-agriculture (including thermoelectric power generation, mining, commercial, and industrial)—and by country for domestic (self-supplied) use. Two child items are included with the dataset: “Domestic groundwater withdrawal rates from the Ozark Plateaus aquifer system, 1900 to 2010” and “Public supply, non-agriculture, livestock, and agriculture groundwater withdrawal rates from the Ozark Plateaus aquifer system, 1900 to 2010”. The Ozark system is located in the central United States and is composed of interbedded Cambrian to Pennsylvanian clastic and carbonate lithologies. In stratigraphic order, the Ozark system includes the Basement confining unit, St. Francois aquifer, St. Francois confining unit, Ozark aquifer, Ozark confining unit, Springfield Plateau aquifer, and Western Interior Plains confining system. Generally, the lower portion of the Ozark aquifer is the primary source of groundwater across much of Missouri and the Springfield Plateau aquifer is used across northern Arkansas. A full description of the methods used to model groundwater withdrawal rates from the Ozark system are available in Knierim et al., IN

  15. Groundwater and climate change research scoping study

    OpenAIRE

    Jackson, C. R.; Cheetham, M.; Guha, P

    2006-01-01

    This scoping study has reviewed much of the published literature in the field of climate change and groundwater research. Whilst it is not exhaustive with regard to groundwater quality issues, most of the published literature relating to climate change and groundwater resources, particularly in the UK, is covered. Further work is required to identify current research needs relating to the effects of climate change on groundwater quality. The study of the effects of climate chan...

  16. Implementing earth observation and advanced satellite based atmospheric sounders for water resource and climate modelling

    DEFF Research Database (Denmark)

    Boegh, E.; Dellwik, Ebba; Hahmann, Andrea N.;

    This paper discusses preliminary remote sensing (MODIS) based hydrological modelling results for the Danish island Sjælland (7330 km2) in relation to project objectives and methodologies of a new research project “Implementing Earth observation and advanced satellite based atmospheric sounders...... for effective land surface representation in water resource modeling” (2009- 2012). The purpose of the new research project is to develop remote sensing based model tools capable of quantifying the relative effects of site-specific land use change and climate variability at different spatial scales....... For this purpose, a) internal catchment processes will be studied using a Distributed Temperature Sensing (DTS) system, b) Earth observations will be used to upscale from field to regional scales, and c) at the largest scale, satellite based atmospheric sounders and meso-scale climate modelling will be used...

  17. Response of Groundwater table to Eucalyptus Plantations in a Tropical Monsoon Climate, Lake Tana Basin, Ethiopia

    Science.gov (United States)

    Enku, Temesgen; Melesse, Assefa; Ayana, Essaya; Tilahun, Seifu; Abate, Mengiste; Steenhuis, Tammo

    2017-04-01

    Given the increasing demand for water resources and the need for better management of regional water resources, it is essential to quantify the groundwater use by phreatophytes in tropical monsoon climates. Phreatophytes, like eucalyptus plantations are reported to be a groundwater sink and it could significantly affect the regional groundwater resources. In our study, the consumptive groundwater use of a closed eucalyptus plantation was calculated based on the diurnal water table fluctuations observed in monitoring wells for two dry monsoon phases in the Fogera plain, northwest of Ethiopia. Automated recorders were installed to monitor the hourly groundwater table fluctuations. The groundwater table fluctuates from maximum at early in the morning to minimum in the evening daily and generally declined linearly during the dry phase averaging 3.1 cm/day during the two year period under the eucalyptus plantations. The hourly eucalypts transpiration rate over the daylight hours follows the daily solar irradiance curve for clear sky days. It is minimal during the night and reaches maximum of 1.65mm/hour at mid-day. The evapotranspiration from the groundwater by eucalyptus plantations during the dry phases was estimated at about 2300mm from October 1 to 31 May, in 2015 compared to about 900mm without eucalyptus trees. The average daily evapotranspiration was 9.6mm. This is almost twice of the reference evapotranspiration in the area and 2.5 times the actual rate under fallow agricultural fields. Thus, water resources planning and management in the region needs to consider the effect of eucalyptus plantations on the availability of groundwater resources in the highlands of Ethiopia. Key words: Eucalyptus, Evapotranspiration, Groundwater, Ethiopia, Lake Tana

  18. The Influence of Land Subsidence, Quarrying, Drainage, Irrigation and Forest Fire on Groundwater Resources and Biodiversity Along the Southern Po Plain Coastal Zone (Italy)

    Science.gov (United States)

    Antonellini, M. A.; Mollema, P. N.

    2014-12-01

    The coastal zone of the southern Po plain is characterized by low lying land, which is reclaimed to permit settlements and agriculture. The history, tourism resorts and peculiar coastal environments make this territory attractive and valuable. Natural and fluid-extraction-induced land subsidence along with coastal erosion are major problems. Touristic development has strongly modified the landscape; coastal dunes have been in part removed to make room for hotels and quarrying has caused the formation of gravel pit lakes close to the shoreline. Protected natural areas include a belt of coastal dunes, wetlands, and the internal historical forests of San Vitale and Classe. The dunes have largely lost their original vegetation ecosystem, because years ago they have been colonized with pine trees to protect the adjacent farmland from sea spray. These pine forests are currently a fire hazard. Land reclamation drainage keeps the water table artificially low. Results of these anthropogenic disturbances on the hydrology include a decrease in infiltration rates, loss of freshwater surface bodies, encroachment of saltwater inland from the river estuaries, salinization of the aquifer, wetlands and soil with a loss in plant and aquatic species biodiversity. Feedback mechanisms are complex: as land subsidence continues, drainage increases at the same pace promoting sea-water intrusion. The salinity of the groundwater does not allow for plant species richness nor for the survival of large pine trees. Farmland irrigation and fires in the pine forests, on the other hand, allow for increased infiltration and freshening of the aquifer and at the same time promote plant species diversity. Our work shows that the characteristics of the southern Po coastal zone require integrated management of economic activities, natural areas, and resources. This approach is different from the ad hoc measures taken so far, because it requires long term planning and setting a priority of objectives.

  19. A Contamination Vulnerability Assessment for the Sacramento Area Groundwater Basin

    Energy Technology Data Exchange (ETDEWEB)

    Moran, J E; Hudson, G B; Eaton, G F; Leif, R

    2004-03-10

    In response to concerns expressed by the California Legislature and the citizenry of the State of California, the State Water Resources Control Board (SWRCB), implemented a program to assess groundwater quality, and provide a predictive capability for identifying areas that are vulnerable to contamination. The program was initiated in response to concern over public supply well closures due to contamination by chemicals such as MtBE from gasoline, and solvents from industrial operations. As a result of this increased awareness regarding groundwater quality, the Supplemental Report of the 1999 Budget Act mandated the SWRCB to develop a comprehensive ambient groundwater-monitoring plan, and led to the initiation of the Ambient Groundwater Monitoring and Assessment (GAMA) Program. The primary objective of the GAMA Program is to assess the water quality and to predict the relative susceptibility to contamination of groundwater resources throughout the state of California. Under the GAMA program, scientists from Lawrence Livermore National Laboratory (LLNL) collaborate with the SWRCB, the U.S. Geological Survey, the California Department of Health Services (DHS), and the California Department of Water Resources (DWR) to implement the groundwater assessment program in cooperation with local water purveyors. In 2001 and 2002, LLNL carried out this vulnerability study in the groundwater basin of Sacramento suburban area, located to the north of the American River and to the east of the Sacramento River. The goal of the study is to provide a probabilistic assessment of the relative vulnerability of groundwater used for the public water supply to contamination from surface sources. This assessment of relative contamination vulnerability is made based on the results of two types of analyses that are not routinely carried out at public water supply wells: ultra low-level measurement of volatile organic compounds (VOCs), and groundwater age dating (using the tritium-helium-3

  20. Disturbance observer based active and adaptive synchronization of energy resource chaotic system.

    Science.gov (United States)

    Wei, Wei; Wang, Meng; Li, Donghai; Zuo, Min; Wang, Xiaoyi

    2016-11-01

    In this paper, synchronization of a three-dimensional energy resource chaotic system is considered. For the sake of achieving the synchronization between the drive and response systems, two different nonlinear control approaches, i.e. active control with known parameters and adaptive control with unknown parameters, have been designed. In order to guarantee the transient performance, finite-time boundedness (FTB) and finite-time stability (FTS) are introduced in the design of active control and adaptive control, respectively. Simultaneously, in view of the existence of disturbances, a new disturbance observer is proposed to estimate the disturbance. The conditions of the asymptotic stability for the closed-loop system are obtained. Numerical simulations are provided to illustrate the proposed approaches.

  1. The Texas Water Observatory: Utilizing Advanced Observing System Design for Understanding Water Resources Sustainability Across Climatic and Geologic Gradients of Texas

    Science.gov (United States)

    Mohanty, B.; Moore, G. W.; Miller, G. R.; Quiring, S. M.; Everett, M. E.; Morgan, C.

    2015-12-01

    The Texas Water Observatory (TWO) is a new distributed network of field observatories for better understanding of the hydrologic flow in the critical zone (encompassing groundwater, soil water, surface water, and atmospheric water) at various space and time scales. Core sites in the network will begin in Brazos River corridor and expand from there westward. Using many advanced observational platforms and real-time / near-real time sensors, this observatory will monitor high frequency data of water stores and fluxes, critical for understanding and modeling the in the state of Texas and Southern USA. Once implemented, TWO will be positioned to support high-impact water science that is highly relevant to societal needs and serve as a regional resource for better understanding and/or managing agriculture, water resources, ecosystems, biodiversity, disasters, health, energy, and weather/climate. TWO infrastructure will span land uses (cultiva