Sample records for water recharge patterns

  1. A digital procedure for ground water recharge and discharge pattern recognition and rate estimation. (United States)

    Lin, Yu-Feng; Anderson, Mary P


    A digital procedure to estimate recharge/discharge rates that requires relatively short preparation time and uses readily available data was applied to a setting in central Wisconsin. The method requires only measurements of the water table, fluxes such as stream baseflows, bottom of the system, and hydraulic conductivity to delineate approximate recharge/discharge zones and to estimate rates. The method uses interpolation of the water table surface, recharge/discharge mapping, pattern recognition, and a parameter estimation model. The surface interpolator used is based on the theory of radial basis functions with thin-plate splines. The recharge/discharge mapping is based on a mass-balance calculation performed using MODFLOW. The results of the recharge/discharge mapping are critically dependent on the accuracy of the water table interpolation and the accuracy and number of water table measurements. The recharge pattern recognition is performed with the help of a graphical user interface (GUI) program based on several algorithms used in image processing. Pattern recognition is needed to identify the recharge/discharge zonations and zone the results of the mapping method. The parameter estimation program UCODE calculates the parameter values that provide a best fit between simulated heads and flows and calibration head-and-flow targets. A model of the Buena Vista Ground Water Basin in the Central Sand Plains of Wisconsin is used to demonstrate the procedure.

  2. The impact of a shallow biobarrier on water recharge patterns in a semi-arid environment

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    Laundre, J.W. [Idaho State Univ., Pocatello, ID (United States)


    This study attempted to measure the effect of a shallow biobarrier of gravel and cobble on water flow patterns during spring snow melt and recharge. The design consisted of 30 metal culverts 3 m in diameter and 1.6 m long, positioned on end. Test culverts contained 50-cm biobarrier of gravel or cobble and then an additional 50 cm of soil placed above the barrier layer. A neutron probe was used to measure soil moisture above and below the barrier. Measurements were made in the fall and again immediately after snow melt in the spring. During recharge, the biobarriers provided a capillary break which resulted in a pooling of water above the barrier layer. With sufficient snowmelt, the water can penetrate the break and possibly penetrate deeper than in the absence of the barrier layer.

  3. Recharge pattern of contemporary glass ionomer restoratives

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    Farahnaz Arbabzadeh-Zavareh


    Full Text Available Background: As glass ionomers have the ability to reload fluoride from outside sources, the aim was to compare the recharge pattern of six glass ionomer cements after exposure to fluoride. Materials and Methods: Fuji VII, Fuji IX, Riva Pink, Riva Bleach, Ketac Fil and Fuji IX Extra were investigated. The fluoride-containing materials used were tooth paste and mouth wash (Colgate. Specimens of each material (n=15 were immersed separately in deionized water for 59 days. Then the samples of each material were divided into three groups of five each. Two groups were recharged for 2, 20 and 60 min daily during three consecutive weekly intervals and then no treatment for one week. The third group was used as control. Fluoride release measurements (μg/cm 2 /day were made in every 24 h. One-way and repeated measures analysis of variance tests were used. Results: Tooth paste recharged materials showed higher level of recharge. On day 1, the difference of fluoride release from different treatment groups of different materials except for Fuji IX Extra were not significant (P>0.05. On days 7 and 14, the differences observed were significant (P<0.05 for all materials except for Fuji VII (tooth paste versus mouth wash and Trial Fuji IX (mouth wash versus control and on day 14 for Rvia Pink (mouth wash versus control. On days 21 and 28, the differences observed were significant for all the materials (P<0.05 except for Riva Pink (toothpaste versus mouth wash, Riva Bleach, Ketac Fil and Trial FujiI X (mouth wash versus control on day 28. Conclusion: A time tabled schedule of application of fluoride-containing materials could help to achieve high fluoride release.

  4. Artificial Ground Water Recharge with Surface Water (United States)

    Heviánková, Silvie; Marschalko, Marian; Chromíková, Jitka; Kyncl, Miroslav; Korabík, Michal


    With regard to the adverse manifestations of the recent climatic conditions, Europe as well as the world have been facing the problem of dry periods that reduce the possibility of drawing drinking water from the underground sources. The paper aims to describe artificial ground water recharge (infiltration) that may be used to restock underground sources with surface water from natural streams. Among many conditions, it aims to specify the boundary and operational conditions of the individual aspects of the artificial ground water recharge technology. The principle of artificial infiltration lies in the design of a technical system, by means of which it is possible to conduct surplus water from one place (in this case a natural stream) into another place (an infiltration basin in this case). This way, the water begins to infiltrate into the underground resources of drinking water, while the mixed water composition corresponds to the water parameters required for drinking water.

  5. Geophysical Methods for Investigating Ground-Water Recharge (United States)

    Ferre, Ty P.A.; Binley, Andrew M.; Blasch, Kyle W.; Callegary, James B.; Crawford, Steven M.; Fink, James B.; Flint, Alan L.; Flint, Lorraine E.; Hoffmann, John P.; Izbicki, John A.; Levitt, Marc T.; Pool, Donald R.; Scanlon, Bridget R.


    While numerical modeling has revolutionized our understanding of basin-scale hydrologic processes, such models rely almost exclusively on traditional measurements?rainfall, streamflow, and water-table elevations?for calibration and testing. Model calibration provides initial estimates of ground-water recharge. Calibrated models are important yet crude tools for addressing questions about the spatial and temporal distribution of recharge. An inverse approach to recharge estimation is taken of necessity, due to inherent difficulties in making direct measurements of flow across the water table. Difficulties arise because recharging fluxes are typically small, even in humid regions, and because the location of the water table changes with time. Deep water tables in arid and semiarid regions make recharge monitoring especially difficult. Nevertheless, recharge monitoring must advance in order to improve assessments of ground-water recharge. Improved characterization of basin-scale recharge is critical for informed water-resources management. Difficulties in directly measuring recharge have prompted many efforts to develop indirect methods. The mass-balance approach of estimating recharge as the residual of generally much larger terms has persisted despite the use of increasing complex and finely gridded large-scale hydrologic models. Geophysical data pertaining to recharge rates, timing, and patterns have the potential to substantially improve modeling efforts by providing information on boundary conditions, by constraining model inputs, by testing simplifying assumptions, and by identifying the spatial and temporal resolutions needed to predict recharge to a specified tolerance in space and in time. Moreover, under certain conditions, geophysical measurements can yield direct estimates of recharge rates or changes in water storage, largely eliminating the need for indirect measures of recharge. This appendix presents an overview of physically based, geophysical methods

  6. Ground water recharge and flow characterization using multiple isotopes. (United States)

    Chowdhury, Ali H; Uliana, Matthew; Wade, Shirley


    Stable isotopes of delta(18)O, delta(2)H, and (13)C, radiogenic isotopes of (14)C and (3)H, and ground water chemical compositions were used to distinguish ground water, recharge areas, and possible recharge processes in an arid zone, fault-bounded alluvial aquifer. Recharge mainly occurs through exposed stream channel beds as opposed to subsurface inflow along mountain fronts. This recharge distribution pattern may also occur in other fault-bounded aquifers, with important implications for conceptualization of ground water flow systems, development of ground water models, and ground water resource management. Ground water along the mountain front near the basin margins contains low delta(18)O, (14)C (percent modern carbon [pmC]), and (3)H (tritium units [TU]), suggesting older recharge. In addition, water levels lie at greater depths, and basin-bounding faults that locally act as a flow barrier may further reduce subsurface inflow into the aquifer along the mountain front. Chemical differences in ground water composition, attributed to varying aquifer mineralogy and recharge processes, further discriminate the basin-margin and the basin-center water. Direct recharge through the indurated sandstones and mudstones in the basin center is minimal. Modern recharge in the aquifer is mainly through the broad, exposed stream channel beds containing coarse sand and gravel where ground water contains higher delta(18)O, (14)C (pmC), and (3)H (TU). Spatial differences in delta(18)O, (14)C (pmC), and (3)H (TU) and occurrences of extensive mudstones in the basin center suggest sluggish ground water movement, including local compartmentalization of the flow system.

  7. Recharge estimation for transient ground water modeling. (United States)

    Jyrkama, Mikko I; Sykes, Jon F; Normani, Stefano D


    Reliable ground water models require both an accurate physical representation of the system and appropriate boundary conditions. While physical attributes are generally considered static, boundary conditions, such as ground water recharge rates, can be highly variable in both space and time. A practical methodology incorporating the hydrologic model HELP3 in conjunction with a geographic information system was developed to generate a physically based and highly detailed recharge boundary condition for ground water modeling. The approach uses daily precipitation and temperature records in addition to land use/land cover and soils data. The importance of the method in transient ground water modeling is demonstrated by applying it to a MODFLOW modeling study in New Jersey. In addition to improved model calibration, the results from the study clearly indicate the importance of using a physically based and highly detailed recharge boundary condition in ground water quality modeling, where the detailed knowledge of the evolution of the ground water flowpaths is imperative. The simulated water table is within 0.5 m of the observed values using the method, while the water levels can differ by as much as 2 m using uniform recharge conditions. The results also show that the combination of temperature and precipitation plays an important role in the amount and timing of recharge in cooler climates. A sensitivity analysis further reveals that increasing the leaf area index, the evaporative zone depth, or the curve number in the model will result in decreased recharge rates over time, with the curve number having the greatest impact.

  8. Artificial recharge of humic ground water. (United States)

    Alborzfar, M; Villumsen, A; Grøn, C


    The purpose of this study was to investigate the efficiency of soil in removing natural organic matter from humic ground waters using artificial recharge. The study site, in western Denmark, was a 10,000 ml football field of which 2,000 m2 served as an infiltration field. The impact of the artificial recharge was studied by monitoring the water level and the quality of the underlying shallow aquifer. The humic ground water contained mainly humic adds with an organic carbon (OC) concentration of 100 to 200 mg C L(-1). A total of 5,000 mS of humic ground water were sprinkled onto the infiltration field at an average rate of 4.25 mm h(-1). This resulted in a rise in the water table of the shallow aquifer. The organic matter concentration of the water in the shallow aquifer, however, remained below 2.7 mg C L(-1). The organic matter concentration of the pore water in the unsaturated zone was measured at the end of the experiment. The organic matter concentration of the pore water decreased from 105 mg C L(-1) at 0.5 m to 20 mg C L(-1) at 2.5 m under the infiltration field indicating that the soil removed the organic matter from the humic ground water. From these results we conclude that artificial recharge is a possible method for humic ground water treatment.

  9. Using MODFLOW 2000 to model ET and recharge for shallow ground water problems. (United States)

    Doble, Rebecca C; Simmons, Craig T; Walker, Glen R


    In environments with shallow ground water elevation, small changes in the water table can cause significant variations in recharge and evapotranspiration fluxes. Particularly, where ground water is close to the soil surface, both recharge and evapotranspiration are regulated by a thin unsaturated zone and, for accuracy, must be represented using nonconstant and often nonlinear relationships. The most commonly used ground water flow model today, MODFLOW, was originally designed with a modular structure with independent packages representing recharge and evaporation processes. Systems with shallow ground water, however, may be better represented using either a recharge function that varies with ground water depth or a continuous recharge and evapotranspiration function that is dependent on depth to water table. In situations where the boundaries between recharging and nonrecharging cells change with time, such as near a seepage zone, a continuous ground water flux relationship allows recharge rates to change with depth rather than having to calculate them at each stress period. This research article describes the modification of the MODFLOW 2000 recharge and segmented evapotranspiration packages into a continuous recharge-discharge function that allows ground water flux to be represented as a continuous process, dependent on head. The modifications were then used to model long-term recharge and evapotranspiration processes on a saline, semiarid floodplain in order to understand spatial patterns of salinization, and an overview of this process is given.

  10. Regional estimation of total recharge to ground water in Nebraska. (United States)

    Szilagyi, Jozsef; Harvey, F Edwin; Ayers, Jerry F


    Naturally occurring long-term mean annual recharge to ground water in Nebraska was estimated by a novel water-balance approach. This approach uses geographic information systems (GIS) layers of land cover, elevation of land and ground water surfaces, base recharge, and the recharge potential in combination with monthly climatic data. Long-term mean recharge > 140 mm per year was estimated in eastern Nebraska, having the highest annual precipitation rates within the state, along the Elkhorn, Platte, Missouri, and Big Nemaha River valleys where ground water is very close to the surface. Similarly high recharge values were obtained for the Sand Hills sections of the North and Middle Loup, as well as Cedar River and Beaver Creek valleys due to high infiltration rates of the sandy soil in the area. The westernmost and southwesternmost parts of the state were estimated to typically receive recharge a year.

  11. Monitoring of recharge water quality under woodland (United States)

    Krajenbrink, G. J. W.; Ronen, D.; Van Duijvenbooden, W.; Magaritz, M.; Wever, D.


    The study compares the quality of groundwater in the water table zone and soil moisture below the root zone, under woodland, with the quality of the regional precipitation. The water quality under forest shows evidence of the effect of atmospheric deposition of acidic components (e.g. SO 2) and ammonia volatilized from land and feed lots. Detailed chemical profiles of the upper meter of groundwater under different plots of forest, at varying distances from cultivated land, were obtained with a multilayer sampler, using the dialysis-cell method. Porous ceramic cups and a vacuum method were used to obtain soil moisture samples at 1.20 m depth under various types of trees, an open spot and arable land, for the period of a year. The investigation took place in the recharge area of a pumping station with mainly mixed forest, downwind of a vast agricultural area with high ammonia volatilization and underlain by an ice-deformed aquifer. Very high NO -3 concentrations were observed in soil moisture and groundwater (up to 21 mg Nl -1) under coniferous forest, especially in the border zone. This raises the question of the dilution capacity of recharge water under woodland in relation to the polluted groundwater under farming land. The buffering capacity of the unsaturated zone varies substantially and locally a low pH (4.5) was observed in groundwater. The large variability of leachate composition on different scales under a forest and the lesser but still significant concentration differences in the groundwater prove the importance of a monitoring system for the actual solute flux into the groundwater.

  12. A regression model to estimate regional ground water recharge. (United States)

    Lorenz, David L; Delin, Geoffrey N


    A regional regression model was developed to estimate the spatial distribution of ground water recharge in subhumid regions. The regional regression recharge (RRR) model was based on a regression of basin-wide estimates of recharge from surface water drainage basins, precipitation, growing degree days (GDD), and average basin specific yield (SY). Decadal average recharge, precipitation, and GDD were used in the RRR model. The RRR estimates were derived from analysis of stream base flow using a computer program that was based on the Rorabaugh method. As expected, there was a strong correlation between recharge and precipitation. The model was applied to statewide data in Minnesota. Where precipitation was least in the western and northwestern parts of the state (50 to 65 cm/year), recharge computed by the RRR model also was lowest (0 to 5 cm/year). A strong correlation also exists between recharge and SY. SY was least in areas where glacial lake clay occurs, primarily in the northwest part of the state; recharge estimates in these areas were in the 0- to 5-cm/year range. In sand-plain areas where SY is greatest, recharge estimates were in the 15- to 29-cm/year range on the basis of the RRR model. Recharge estimates that were based on the RRR model compared favorably with estimates made on the basis of other methods. The RRR model can be applied in other subhumid regions where region wide data sets of precipitation, streamflow, GDD, and soils data are available.

  13. [Effects of reclaimed water recharge on groundwater quality: a review]. (United States)

    Chen, Wei-Ping; Lü, Si-Dan; Wang, Mei-E; Jiao, Wen-Tao


    Reclaimed water recharge to groundwater is an effective way to relieve water resource crisis. However, reclaimed water contains some pollutants such as nitrate, heavy metals, and new type contaminants, and thus, there exists definite environmental risk in the reclaimed water recharge to groundwater. To promote the development of reclaimed water recharge to groundwater and the safe use of reclaimed water in China, this paper analyzed the relevant literatures and practical experiences around the world, and summarized the effects of different reclaimed water recharge modes on the groundwater quality. Surface recharge makes the salt and nitrate contents in groundwater increased but the risk of heavy metals pollution be smaller, whereas well recharge can induce the arsenic release from sedimentary aquifers, which needs to be paid more attention to. New type contaminants are the hotspots in current researches, and their real risks are unknown. Pathogens have less pollution risks on groundwater, but some virus with strong activity can have the risks. Some suggestions were put forward to reduce the risks associated with the reclaimed water recharge to groundwater in China.

  14. Natural water purification and water management by artificial groundwater recharge. (United States)

    Balke, Klaus-Dieter; Zhu, Yan


    Worldwide, several regions suffer from water scarcity and contamination. The infiltration and subsurface storage of rain and river water can reduce water stress. Artificial groundwater recharge, possibly combined with bank filtration, plant purification and/or the use of subsurface dams and artificial aquifers, is especially advantageous in areas where layers of gravel and sand exist below the earth's surface. Artificial infiltration of surface water into the uppermost aquifer has qualitative and quantitative advantages. The contamination of infiltrated river water will be reduced by natural attenuation. Clay minerals, iron hydroxide and humic matter as well as microorganisms located in the subsurface have high decontamination capacities. By this, a final water treatment, if necessary, becomes much easier and cheaper. The quantitative effect concerns the seasonally changing river discharge that influences the possibility of water extraction for drinking water purposes. Such changes can be equalised by seasonally adapted infiltration/extraction of water in/out of the aquifer according to the river discharge and the water need. This method enables a continuous water supply over the whole year. Generally, artificially recharged groundwater is better protected against pollution than surface water, and the delimitation of water protection zones makes it even more save.

  15. Natural water purification and water management by artificial groundwater recharge

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    Klaus-Dieter BALKE; Yan ZHU


    Worldwide, several regions suffer from water scarcity and contamination. The infiltration and subsurface storage of rain and fiver water can reduce water stress. Artificial groundwater recharge, possibly combined with bank filtration, plant puri- fication and/or the use of subsurface dams and artificial aquifers, is especially advantageous in areas where layers of gravel and sand exist below the earth's surface. Artificial infiltration of surface water into the uppermost aquifer has qualitative and quanti-tative advantages. The contamination of infiltrated fiver water will be reduced by natural attenuation. Clay minerals, iron hy-droxide and humic matter as well as microorganisms located in the subsurface have high decontamination capacities. By this, a final water treatment, if necessary, becomes much easier and cheaper. The quantitative effect concerns the seasonally changing fiver discharge that influences the possibility of water extraction for drinking water purposes. Such changes can be equalised by seasonally adapted infiltration/extraction of water in/out of the aquifer according to the fiver discharge and the water need. This method enables a continuous water supply over the whole year. Generally, artificially recharged groundwater is better protected against pollution than surface water, and the delimitation of water protection zones makes it even more save.

  16. Ground-Water Recharge in the Arid and Semiarid Southwestern United States (United States)

    Stonestrom, David A.; Constantz, Jim; Ferre, Ty P.A.; Leake, Stanley A.


    Ground-water recharge in the arid and semiarid southwestern United States results from the complex interplay of climate, geology, and vegetation across widely ranging spatial and temporal scales. Present-day recharge tends to be narrowly focused in time and space. Widespread water-table declines accompanied agricultural development during the twentieth century, demonstrating that sustainable ground-water supplies are not guaranteed when part of the extracted resource represents paleorecharge. Climatic controls on ground-water recharge range from seasonal cycles of summer monsoonal and winter frontal storms to multimillennial cycles of glacial and interglacial periods. Precipitation patterns reflect global-scale interactions among the oceans, atmosphere, and continents. Large-scale climatic influences associated with El Ni?o and Pacific Decadal Oscillations strongly, but irregularly, control weather in the study area, so that year-to-year variations in precipitation and ground-water recharge are large and difficult to predict. Proxy data indicate geologically recent periods of naturally occurring multidecadal droughts unlike any in the modern instrumental record. Any anthropogenically induced climate change will likely reduce ground-water recharge through diminished snowpack at higher elevations. Future changes in El Ni?o and monsoonal patterns, both crucial to precipitation in the study area, are highly uncertain in current models. Current land-use modifications influence ground-water recharge through vegetation, irrigation, and impermeable area. High mountain ranges bounding the study area?the San Bernadino Mountains and Sierra Nevada to the west, and the Wasatch and southern Colorado Rocky Mountains to the east?provide external geologic controls on ground-water recharge. Internal geologic controls stem from tectonic processes that led to numerous, variably connected alluvial-filled basins, exposure of extensive Paleozoic aquifers in mountainous recharge areas

  17. The character of organic carbon in recharge water and arsenic mobilization in Bangladesh aquifers (United States)

    Pracht, L. E.; Fussell, A. H.; Polizzotto, M.; Badruzzaman, A. M.; Ali, M. A.; Neumann, R. B.


    In Bangladesh, arsenic-contaminated groundwater, used for both drinking and irrigation supplies, negatively affects the health of millions of people. Past work at our site in Munshiganj suggests that current patterns of arsenic concentration in the aquifer are related to groundwater flow and recharge chemistry. Constructed ponds and groundwater-irrigated rice fields serve as the primary aquifer recharge sources, with pond recharge evolving into high-arsenic groundwater and rice field recharge evolving into low-arsenic groundwater. The composition of these water types vary in concentrations and character of dissolved organic carbon, a presumed key component in the mechanism of arsenic release from sediments. Here we present results from an experiment-based laboratory study that directly tests the role of organic carbon character and bioavailability on arsenic mobilization. Incubation experiments using sediment samples collected from Bangladesh and waters with different carbon sources (e.g., pond and rice field recharge water and artificial water with model carbon compounds) were conducted to show the phase transformations carbon undergoes during arsenic mobilization processes, to isolate the carbon components and characteristics most responsible for mobilization reactions, and to investigate the importance of secondary chemical constituents for completion of these physiochemical reactions. Water, gas, and sediment samples collected from the incubations were analyzed for nutrient, metal, anion, and carbon concentrations, as well as carbon character. The results clarify the chemical components most critical in arsenic mobilization and provide insight into the in situ chemical reactions occurring in the aquifer. Moreover, this better chemical understanding helps elucidate the potential impact of altered recharge patterns and recharge chemistry on arsenic concentrations of Bangladeshi groundwater supplies.

  18. Thermal Methods for Investigating Ground-Water Recharge (United States)

    Blasch, Kyle W.; Constantz, Jim; Stonestrom, David A.


    Recharge of aquifers within arid and semiarid environments is defined as the downward flux of water across the regional water table. The introduction of recharging water at the land surface can occur at discreet locations, such as in stream channels, or be distributed over the landscape, such as across broad interarroyo areas within an alluvial ground-water basin. The occurrence of recharge at discreet locations is referred to as focused recharge, whereas the occurrence of recharge over broad regions is referred to as diffuse recharge. The primary interest of this appendix is focused recharge, but regardless of the type of recharge, estimation of downward fluxes is essential to its quantification. Like chemical tracers, heat can come from natural sources or be intentionally introduced to infer transport properties and aquifer recharge. The admission and redistribution of heat from natural processes such as insolation, infiltration, and geothermal activity can be used to quantify subsurface flow regimes. Heat is well suited as a ground-water tracer because it provides a naturally present dynamic signal and is relatively harmless over a useful range of induced perturbations. Thermal methods have proven valuable for recharge investigations for several reasons. First, theoretical descriptions of coupled water-and-heat transport are available for the hydrologic processes most often encountered in practice. These include land-surface mechanisms such as radiant heating from the sun, radiant cooling into space, and evapotranspiration, in addition to the advective and conductive mechanisms that usually dominate at depth. Second, temperature is theoretically well defined and readily measured. Third, thermal methods for depths ranging from the land surface to depths of hundreds of meters are based on similar physical principles. Fourth, numerical codes for simulating heat and water transport have become increasingly reliable and widely available. Direct measurement of water

  19. Estimating ground water recharge from topography, hydrogeology, and land cover. (United States)

    Cherkauer, Douglas S; Ansari, Sajjad A


    Proper management of ground water resources requires knowledge of the rates and spatial distribution of recharge to aquifers. This information is needed at scales ranging from that of individual communities to regional. This paper presents a methodology to calculate recharge from readily available ground surface information without long-term monitoring. The method is viewed as providing a reasonable, but conservative, first approximation of recharge, which can then be fine-tuned with other methods as time permits. Stream baseflow was measured as a surrogate for recharge in small watersheds in southeastern Wisconsin. It is equated to recharge (R) and then normalized to observed annual precipitation (P). Regression analysis was constrained by requiring that the independent and dependent variables be dimensionally consistent. It shows that R/P is controlled by three dimensionless ratios: (1) infiltrating to overland water flux, (2) vertical to lateral distance water must travel, and (3) percentage of land cover in the natural state. The individual watershed properties that comprise these ratios are now commonly available in GIS data bases. The empirical relationship for predicting R/P developed for the study watersheds is shown to be statistically viable and is then tested outside the study area and against other methods of calculating recharge. The method produces values that agree with baseflow separation from streamflow hydrographs (to within 15% to 20%), ground water budget analysis (4%), well hydrograph analysis (12%), and a distributed-parameter watershed model calibrated to total streamflow (18%). It has also reproduced the temporal variation over 5 yr observed at a well site with an average error < 12%.

  20. Water quality management of aquifer recharge using advanced tools. (United States)

    Lazarova, Valentina; Emsellem, Yves; Paille, Julie; Glucina, Karl; Gislette, Philippe


    Managed aquifer recharge (MAR) with recycled water or other alternative resources is one of the most rapidly growing techniques that is viewed as a necessity in water-short areas. In order to better control health and environmental effects of MAR, this paper presents two case studies demonstrating how to improve water quality, enable reliable tracing of injected water and better control and manage MAR operation in the case of indirect and direct aquifer recharge. Two water quality management strategies are illustrated on two full-scale case studies, including the results of the combination of non conventional and advanced technologies for water quality improvement, comprehensive sampling and monitoring programs including emerging pollutants, tracer studies using boron isotopes and integrative aquifer 3D GIS hydraulic and hydrodispersive modelling.

  1. Trace organic chemicals contamination in ground water recharge. (United States)

    Díaz-Cruz, M Silvia; Barceló, Damià


    Population growth and unpredictable climate changes will pose high demands on water resources in the future. Even at present, surface water is certainly not enough to cope with the water requirement for agricultural, industrial, recreational and drinking purposes. In this context, the usage of ground water has become essential, therefore, their quality and quantity has to be carefully managed. Regarding quantity, artificial recharge can guarantee a sustainable level of ground water, whilst the strict quality control of the waters intended for recharge will minimize contamination of both the ground water and aquifer area. However, all water resources in the planet are threatened by multiple sources of contamination coming from the extended use of chemicals worldwide. In this respect, the environmental occurrence of organic micropollutants such as pesticides, pharmaceuticals, industrial chemicals and their metabolites has experienced fast growing interest. In this paper an overview of the priority and emerging organic micropollutants in the different source waters used for artificial aquifer recharge purposes and in the recovered water is presented. Besides, some considerations regarding fate and removal of such compounds are also addressed.

  2. Water Conservation and Artificial Recharge of Aquifers in India

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    Chandha, D. K.


    India has proud traditions and wisdom which have evolved over thousands of years for developing technologies for water conservation and groundwater recharge using surplus monsoon precipitation runoff. This is imperative as the average rainfall/precipitation period is about 27 days/year and with uneven distribution across the country. Groundwater development is now the mainstay for sustaining agricultural production and rural water supplies. As such, groundwater development is increasing at an exponential rate and the estimated draft is now 231 000 hm{sup 3} with the result that almost 15% of the groundwater development areas are showing a continuous decline of water levels. There is an anomalous situation whereby water levels are declining in 831 blocks (assessment units) out of a total of 5 723 blocks across the country, and availability of excessive 864 000 hm{sup 3} runoff in different river basins brings floods and creates water logging in some parts of the country. This non-utilizable water can be planned for creating small surface water storage and to create additional sub-surface storage through groundwater recharge. At present, total water available is estimated at 660 000 hm{sup 3} and the minimum estimated water demand will be 843 000 hm{sup 3} in 2025 and 973 000 hm{sup 3} in 2050. Therefore, if India wants sustainable food supplies and to meet domestic/industrial water requirements, there is no other option than to implement projects for water conservation/groundwater recharge. Although a number of forward looking steps have been planned by the government and other institutions, many lacunae have been observed which need to be addressed for the successful implementation of water conservation and recharge programmes. This paper discusses various practices from the pre-historic to the present day, with case studies showing technological intervention. (Author)

  3. California GAMA Special Study: Importance of River Water Recharge to Selected Groundwater Basins

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    Visser, Ate [Lawrence Livermore National Lab. (LLNL), Livermore, CA (United States); Moran, Jean E. [California State Univ. East Bay (CalState), Hayward, CA (United States); Singleton, Michael J. [Lawrence Livermore National Lab. (LLNL), Livermore, CA (United States); Esser, Bradley K. [Lawrence Livermore National Lab. (LLNL), Livermore, CA (United States)


    River recharge represents 63%, 86% and 46% of modern groundwater in the Mojave Desert, Owens Valley, and San Joaquin Valley, respectively. In pre-modern groundwater, river recharge represents a lower fraction: 36%, 46%, and 24% respectively. The importance of river water recharge in the San Joaquin valley has nearly doubled and is likely the result of a total increase of recharge of 40%, caused by river water irrigation return flows. This emphasizes the importance of recharge of river water via irrigation for renewal of groundwater resources. Mountain front recharge and local precipitation contribute to recharge of desert groundwater basins in part as the result of geological features focusing scarce precipitation promoting infiltration. River water recharges groundwater systems under lower temperatures and with larger water table fluctuations than local precipitation recharge. Surface storage is limited in time and volume, as evidenced by cold river recharge temperatures resulting from fast recharge, compared to the large capacity for subsurface storage. Groundwater banking of seasonal surface water flows therefore appears to be a natural and promising method for increasing the resilience of water supply systems. The distinct isotopic and noble gas signatures of river water recharge, compared to local precipitation recharge, reflecting the source and mechanism of recharge, are valuable constraints for numerical flow models.

  4. Soil Water Balance and Recharge Monitoring at the Hanford Site – FY 2010 Status Report

    Energy Technology Data Exchange (ETDEWEB)

    Fayer, Michael J.; Saunders, Danielle L.; Herrington, Ricky S.; Felmy, Diana


    This report summarizes the recharge data collected in FY 2010 at five locations on the Hanford Site in southeastern Washington State. Average monthly precipitation and temperature conditions in FY 2010 were near normal and did not present an opportunity for increased recharge. The recharge monitoring data confirmed those conditions, showing normal behavior in water content, matric head, and recharge rates. Also provided in this report is a strategy for recharge estimation for the next 5 years.

  5. Movement of water infiltrated from a recharge basin to wells. (United States)

    O'Leary, David R; Izbicki, John A; Moran, Jean E; Meeth, Tanya; Nakagawa, Brandon; Metzger, Loren; Bonds, Chris; Singleton, Michael J


    Local surface water and stormflow were infiltrated intermittently from a 40-ha basin between September 2003 and September 2007 to determine the feasibility of recharging alluvial aquifers pumped for public supply, near Stockton, California. Infiltration of water produced a pressure response that propagated through unconsolidated alluvial-fan deposits to 125 m below land surface (bls) in 5 d and through deeper, more consolidated alluvial deposits to 194 m bls in 25 d, resulting in increased water levels in nearby monitoring wells. The top of the saturated zone near the basin fluctuates seasonally from depths of about 15 to 20 m. Since the start of recharge, water infiltrated from the basin has reached depths as great as 165 m bls. On the basis of sulfur hexafluoride tracer test data, basin water moved downward through the saturated alluvial deposits until reaching more permeable zones about 110 m bls. Once reaching these permeable zones, water moved rapidly to nearby pumping wells at rates as high as 13 m/d. Flow to wells through highly permeable material was confirmed on the basis of flowmeter logging, and simulated numerically using a two-dimensional radial groundwater flow model. Arsenic concentrations increased slightly as a result of recharge from 2 to 6 µg/L immediately below the basin. Although few water-quality issues were identified during sample collection, high groundwater velocities and short travel times to nearby wells may have implications for groundwater management at this and at other sites in heterogeneous alluvial aquifers.

  6. The Use Of Permeable Concrete For Ground Water Recharge

    Directory of Open Access Journals (Sweden)

    Akshay Tejankar


    Full Text Available In order to develop Smart Cities in India, we need to develop smart technologies and smart construction materials. Permeable concrete an innovative material is environment friendly and a smart material which can be used for construction of several structures. In India, the ground water table is decreasing at a faster rate due to reduction in ground water recharge. These days, the vegetation cover is replaced by infrastructure hence the water gets very less opportunity to infiltrate itself into the soil. If the permeable concrete which has a high porosity is used for the construction of pavements, walking tracks, parking lots, well lining, etc. then it can reduce the runoff from the site and help in the ground water recharge. Such type of smart materials will play an important role for Indian conditions where government is putting lot of efforts to implement ground water recharging techniques. During the research work, the runoff for a particular storm was calculated for a bitumen pavement on a sloping ground. Later after studying the various topographical features, the traffic intensity and the rainfall for that particular area, the concrete was designed and tested for the different proportion and thus the mix design for the permeable concrete was finalized based upon its permeability and strength characteristics. Later by using this permeable concrete the infiltration and runoff for the same storm was compared and studied. The research paper will thus give an account of the properties of permeable concrete where it can be used over an existing road.

  7. Aquifer characteristics and groundwater recharge pattern in a typical ...

    African Journals Online (AJOL)


    IFO JUNCTION ... precipitation and secondarily through lateral flow from rivers and .... recharge and groundwater through flow (Wright, 1992). ..... T. IT. U. D. E. Scale(m). 0. 50 100 150 200. LONGITUDE. Figure 4a. Contour maps showing ...

  8. PRO-GRADE: GIS toolkits for ground water recharge and discharge estimation. (United States)

    Lin, Yu-Feng; Wang, Jihua; Valocchi, Albert J


    PRO-GRADE is an ESRI ArcGIS 9.2 plug-in package that consists of two separate toolkits: (1) the pattern recognition organizer for geographic information system (PRO-GIS) and (2) the ground water recharge and discharge estimator for GIS (GRADE-GIS). PRO-GIS is a collection of several existing image-processing algorithms into one user interface to offer the flexibility to extract spatial patterns according to the user's needs. GRADE-GIS is a ground water recharge and discharge estimation interface using a mass balance method that requires only hydraulic conductivity, water table, and bedrock elevation data for simulating two-dimensional steady-state unconfined aquifers. PRO-GRADE was developed to assist ongoing assessments of the water resources in Illinois and Wisconsin, and is being used to assist several ground water resource studies in several locations in the United States. The advantage of using PRO-GRADE is to enable fast production of initial recharge and discharge maps that can be further enhanced by using a follow-up ground water flow model with parameter estimation codes. PRO-GRADE leverages ArcGIS to provide a computer-assisted framework to support expert judgment in order to efficiently select alternative recharge and discharge maps that can be used as (1) guidelines for field study planning and decision making; (2) initial conditions for numerical simulation; and (3) screening for alternative model selection and prediction/parameter uncertainty evaluation. In addition, PRO-GRADE allows for more easy and rapid correlation of those maps with other hydrologically relevant geospatial data.

  9. Optimization of control bars patterns and fuel recharges of coupled form; Optimizacion de patrones de barras de control y recargas de combustible de forma acoplada

    Energy Technology Data Exchange (ETDEWEB)

    Mejia S, D.M.; Ortiz S, J.J. [ININ, 52750 Ocoyoacac, Estado de Mexico (Mexico)]. e-mail:


    In this work a system coupled for the optimization of fuel recharges and control bars patterns in boiling water reactors (BWR by its initials in English) is presented. It was used a multi state recurrent neural net like optimization technique. This type of neural net has been used in the solution of diverse problems, in particular the design of patterns of control bars and the design of the fuel recharge. However, these problems have been resolved in an independent way with different optimization techniques. The system was developed in FORTRAN 77 language, it calls OCORN (Optimization of Cycles of Operation using Neural Nets) and it solves both problems of combinatory optimization in a coupled way. OCORN begins creating a seed recharge by means of an optimization through the Haling principle. Later on a pattern of control bars for this recharge seed is proposed. Then a new fuel recharge is designed using the control bars patterns previously found. By this way an iterative process begins among the optimization of control bars patterns and the fuel recharge until a stop criteria it is completed. The stop criteria is completed when the fuel recharges and the control bars patterns don't vary in several successive iterations. The final result is an optimal fuel recharge and its respective control bars pattern. In this work the obtained results by this system for a cycle of balance of 18 months divided in 12 steps of burnt are presented. The obtained results are very encouraging, since the fuel recharge and the control bars pattern, its fulfill with the restrictions imposed in each one of the problems. (Author)

  10. Statistical study to identify the key factors governing ground water recharge in the watersheds of the arid Central Asia. (United States)

    Zhu, Binq-Qi; Wang, Yue-Ling


    Understanding the source and recharge of ground waters is of great significance to our knowledge in hydrological cycles in arid environments over the world. Northern Xinjiang in northwestern China is a significant repository of information relating to the hydrological evolution and climatic changes in central Asia. In this study, two multivariate statistical techniques, hierarchical cluster analysis (HCA) and principal component analysis (PCA), were used to assess the ground water recharge and its governing factors, with the principal idea of exploring the above techniques to utilize all available hydrogeochemical variables in the quality assessment, which are not considered in the conventional techniques like Stiff and Piper diagrams. Q-mode HCA and R-mode PCA were combined to partition the water samples into seven major water clusters (C1-C7) and three principal components (PC1-PC3, PC1 salinity, PC2 hydroclimate, PC3 contaminant). The water samples C1 + C4 were classified as recharge area waters (Ca-HCO3 water), C2 + C3 as transitional zone waters (Ca-Mg-HCO3-SO4 water), and C5 + C6 + C7 as discharge area waters (Na-SO4 water). Based on the Q-mode PCA scores, three groups of geochemical processes influencing recharge regimes were identified: geogenic (i.e., caused by natural geochemical processes), geomorphoclimatic (caused by topography and climate), and anthropogenic (caused by ground water contamination). It is proposed that differences in recharge mechanism and ground water evolution, and possible bedrock composition difference, are responsible for the chemical genesis of these waters. These will continue to influence the geochemistry of the northern Xinjiang drainage system for a long time due to its steady tectonics and arid climate. This study proved that the chemistry differentiation of ground water can effectively support the identification of ground water recharge and evolution patterns.

  11. Selected techniques for monitoring water movement through unsaturated alluvium during managed aquifer recharge (United States)

    Nawikas, Joseph M.; O'Leary, David R.; Izbicki, John A.; Burgess, Matthew K.


    Managed aquifer recharge is used to augment natural recharge to aquifers. It can be used to replenish aquifers depleted by pumping or to store water during wetter years for withdrawal during drier years. Infiltration from ponds is a commonly used, inexpensive approach for managed aquifer recharge.At some managed aquifer-recharge sites, the time when infiltrated water arrives at the water table is not always clearly shown by water-level data. As part of site characterization and operation, it can be desirable to track downward movement of infiltrated water through the unsaturated zone to identify when it arrives at the water table.

  12. Geochemical Signature of Natural Water Recharge in the Jungar Basin and Its Response to Climate. (United States)

    Zhu, Bingqi; Yu, Jingjie; Rioual, Patrick


    This paper analyzed the physico-chemical characteristics of natural waters in a drainage system of the Jungar Basin, northwestern China to identify chemical evolution and recharge mechanisms of natural waters in an arid environment. The waters studied are different in mineralization, but are typically carbonate rivers and alkaline in nature. No Cl-dominated water type occurs, indicating an early stage of water evolution. Regolith and geomorphological parameters controlling ground-surface temperature may play a large role in the geological evolution of the water. Three main morphological and hydrological units are reflected in water physico-chemistry. Climate influences the salinization of natural waters substantially. Direct recharge from seasonal snow and ice-melt water and infiltration of rain to the ground are significant recharge processes for natural waters, but recharge from potential deep groundwater may be less important. The enrichment of ions in lakes has been mainly caused by evaporation rather than through the quality change of the recharged water.

  13. Estimated ground-water recharge from streamflow in Fortymile Wash near Yucca Mountain, Nevada

    Energy Technology Data Exchange (ETDEWEB)

    Savard, C.S.


    The two purposes of this report are to qualitatively document ground-water recharge from stream-flow in Fortymile Wash during the period 1969--95 from previously unpublished ground-water levels in boreholes in Fortymile Canyon during 1982--91 and 1995, and to quantitatively estimate the long-term ground-water recharge rate from streamflow in Fortymile Wash for four reaches of Fortymile Wash (Fortymile Canyon, upper Jackass Flats, lower Jackass Flats, and Amargosa Desert). The long-term groundwater recharge rate was estimated from estimates of the volume of water available for infiltration, the volume of infiltration losses from streamflow, the ground-water recharge volume from infiltration losses, and an analysis of the different periods of data availability. The volume of water available for infiltration and ground-water recharge in the four reaches was estimated from known streamflow in ephemeral Fortymile Wash, which was measured at several gaging station locations. The volume of infiltration losses from streamflow for the four reaches was estimated from a streamflow volume loss factor applied to the estimated streamflows. the ground-water recharge volume was estimated from a linear relation between infiltration loss volume and ground-water recharge volume for each of the four reaches. Ground-water recharge rates were estimated for three different periods of data availability (1969--95, 1983--95, and 1992--95) and a long-term ground-water recharge rate estimated for each of the four reaches.

  14. Karst Aquifer Recharge: Comments on Somaratne, N. Characteristics of Point Recharge in Karst Aquifers. Water 2014, 6, 2782–2807

    Directory of Open Access Journals (Sweden)

    Adrian D. Werner


    Full Text Available The article “Characteristics of Point Recharge in Karst Aquifers, Water 6: 2782–2807” by N. Somaratne evaluates various recharge estimation techniques applied to four limestone aquifers in South Australia. Somaratne [1] concludes that methods based on watertable fluctuations, groundwater modelling and water budgets are independent of recharge processes, and are therefore superior to the chloride mass balance (CMB approach for karst aquifers. The current comment offers alternative interpretations from existing field measurements and previous literature, in particular for the Uley South aquifer, which is the focus of much of the article by Somaratne [1]. Conclusions regarding this system are revised, partly to account for the misrepresentation of previous studies. The aeolianite sediments of Uley South are mostly unconsolidated or poorly consolidated, and dissolution features in the calcrete capping provide point infiltration into a predominantly unconsolidated vadose zone, whereas Somaratne’s [1] findings require that the system comprises well-developed conduits in otherwise low-conductivity limestone. Somaratne’s [1] assertion that the basic premise of CMB is violated in Uley South is disputable, given strong evidence of relatively well-mixed groundwater arising from mostly diffuse recharge. The characterization of karst aquifer recharge should continue to rely on multiple techniques, including environmental tracers such as chloride.

  15. An overview of experiences of basin artificial recharge of ground water in Japan (United States)

    Hida, Noboru

    In this paper, the author reviews the present situation of basin artificial recharge of ground water (MAR: managed aquifer recharge) as of 2007 in Japan. Most of the artificial recharge of basin method is carried out using alluvial fans. The enhancing groundwater resources in the Rokugo alluvial aquifer has resulted in sustainability for the groundwater environment, especially in the distal fan. As a general judgment, the basin artificial recharge contributes to sustainable aquifer management in alluvium. As a result of this review, the basin artificial recharge will be utilized more in the future, not only in Japan, but in monsoon Asian countries as well.

  16. Policy and Economics of Managed Aquifer Recharge and Water Banking

    Directory of Open Access Journals (Sweden)

    Sharon B. Megdal


    Full Text Available Managed Aquifer Recharge (MAR and water banking are of increasing importance to water resources management. MAR can be used to buffer against drought and changing or variable climate, as well as provide water to meet demand growth, by making use of excess surface water supplies and recycled waters. Along with hydrologic and geologic considerations, economic and policy analyses are essential to a complete analysis of MAR and water banking opportunities. The papers included in this Special Issue fill a gap in the literature by revealing the range of economic and policy considerations relevant to the development and implementation of MAR programs. They illustrate novel techniques that can be used to select MAR locations and the importance and economic viability of MAR in semi-arid to arid environments. The studies explain how MAR can be utilized to meet municipal and agricultural water demands in water-scarce regions, as well as assist in the reuse of wastewater. Some papers demonstrate how stakeholder engagement, ranging from consideration of alternatives to monitoring, and multi-disciplinary analyses to support decision-making are of high value to development and implementation of MAR programs. The approaches discussed in this collection of papers, along with the complementary and necessary hydrologic and geologic analyses, provide important inputs to water resource managers.

  17. Ground-water recharge in Escambia and Santa Rosa Counties, Florida (United States)

    Grubbs, J.W.


    Ground water is a major component of Florida's water resources, accounting for 90 percent of all public-supply and self-supplied domestic water withdrawals, and 58 percent of self-supplied commercial-industrial and agricultural withdrawals of freshwater (Marella, 1992). Ground-water is also an important source of water for streams, lakes, and wetlands in Florida. Because of their importance, a good understanding of these resources is essential for their sound development, use, and protection. One area in which our understanding is lacking is in characterizing the rate at which ground water in aquifers is recharged, and how recharge rates vary geographically. Ground-water recharge (recharge) is the replenishment of ground water by downward infiltration of water from rainfall, streams, and other sources (American Society of Civil Engineers, 1987, p. 222). The recharge rates in many areas of Florida are unknown, of insufficient accuracy, or mapped at scales that are too coarse to be useful. Improved maps of recharge rates will result in improved capabilities for managing Florida's ground-water resources. In 1989, the U.S. Geological Survey, in cooperation with the Florida Department of Environmental Regulation, began a study to delineate high-rate recharge areas in several regions of Florida (Vecchioli and others, 1990). This study resulted in recharge maps that delineated areas of high (greater than 10 inches per year) and low (0 to 10 inches per year) recharge in three counties--Okaloosa, Pasco, and Volusia Counties--at a scale of 1:100,000. This report describes the results of a similar recharge mapping study for Escambia and Santa Rosa Counties (fig. 1), in which areas of high- and low-rates of recharge to the sand-and-gravel aquifer and Upper Floridan aquifer are delineated. The study was conducted in 1992 and 1993 by the U.S. Geological Survey in cooperation with the Florida Department of Environmental Protection.

  18. Water circulation and recharge pathways of coastal lakes along the southern Baltic Sea in northern Poland

    Directory of Open Access Journals (Sweden)

    Cieśliński Roman


    Full Text Available The purpose of this paper is to describe water circulation patterns for selected lakes found along the Baltic coast in northern Poland and to determine primary recharge mechanisms or pathways that produce an influx or loss of lake water. A secondary purpose of the paper is to determine the magnitude of recharge for each studied source of water – river water influx, surface runoff from direct catchments, forced influx from polders surrounding lakes, and periodic marine water intrusions from the nearby Baltic Sea. It is also important to determine the magnitude of water outflow from lakes to the sea via existing linkages as well as to compare horizontal influx and outflow data. The study area consisted of five lakes located along the Baltic Sea in northern Poland: Łebsko, Gardno, Bukowo, Kopań, Resko Przymorskie. The main driving force of the studied lakes are large rivers that drain lake catchment areas and periodic brackish water intrusions by the Baltic Sea.

  19. Dynamics of flood water infiltration and ground water recharge in hyperarid desert. (United States)

    Dahan, Ofer; Tatarsky, Boaz; Enzel, Yehouda; Kulls, Christoph; Seely, Mary; Benito, Gererdo


    A study on flood water infiltration and ground water recharge of a shallow alluvial aquifer was conducted in the hyperarid section of the Kuiseb River, Namibia. The study site was selected to represent a typical desert ephemeral river. An instrumental setup allowed, for the first time, continuous monitoring of infiltration during a flood event through the channel bed and the entire vadose zone. The monitoring system included flexible time domain reflectometry probes that were designed to measure the temporal variation in vadose zone water content and instruments to concurrently measure the levels of flood and ground water. A sequence of five individual floods was monitored during the rainy season in early summer 2006. These newly generated data served to elucidate the dynamics of flood water infiltration. Each flood initiated an infiltration event which was expressed in wetting of the vadose zone followed by a measurable rise in the water table. The data enabled a direct calculation of the infiltration fluxes by various independent methods. The floods varied in their stages, peaks, and initial water contents. However, all floods produced very similar flux rates, suggesting that the recharge rates are less affected by the flood stages but rather controlled by flow duration and available aquifer storage under it. Large floods flood the stream channel terraces and promote the larger transmission losses. These, however, make only a negligible contribution to the recharge of the ground water. It is the flood duration within the active streambed, which may increase with flood magnitude that is important to the recharge process.

  20. 3H and 14C as tracers of ground-water recharge (United States)

    Izbicki, John A.; Michel, Robert L.; Martin, Peter


    Surface spreading of water from the Santa Clara River is used to recharge aquifers underlying the Oxnard Plain. These aquifers are divided into an upper system about 400 feet thick, and a lower system more than 1,000 feet thick. In previous studies, it has been reported that surface spreading recharged aquifers in both the upper and lower systems. Water from most wells perforated in the upper system has tritium levels consistent with decay-corrected concentrations found in water recharged after 1952 when tritium levels increased as a result of atmospheric testing of nuclear weapons. Water from most wells in the lower system does not contain measurable tritium and must have been recharged prior to 1952. Carbon-14 ages estimated for water from wells in the lower system range from recent to about 25,000 years before present. These data show that the lower system is not effectively recharged by surface spreading.

  1. Soil Water Balance and Recharge Monitoring at the Hanford Site - FY09 Status Report

    Energy Technology Data Exchange (ETDEWEB)

    Rockhold, Mark L.; Saunders, Danielle L.; Strickland, Christopher E.; Waichler, Scott R.; Clayton, Ray E.


    Recharge provides the primary driving force for transporting contaminants from the vadose zone to underlying aquifer systems. Quantification of recharge rates is important for assessing contaminant transport and fate and for evaluating remediation alternatives. This report describes the status of soil water balance and recharge monitoring performed by Pacific Northwest National Laboratory at the Hanford Site for Fiscal Year 2009. Previously reported data for Fiscal Years 2004 - 2008 are updated with data collected in Fiscal Year 2009 and summarized.

  2. Portrayal of fuzzy recharge areas for water balance modelling - a case study in northern Oman (United States)

    Gerner, A.; Schütze, N.; Schmitz, G. H.


    The research project IWAS Oman aims at implementing integrated water resources management (IWRM) to a pilot area in Al Batinah, Oman. This requires - amongst others - a realistic assessment of groundwater recharge to the alluvial aquifer which obviously has to be based upon the extension of recharge areas. In this context, the subsequent investigation focuses on the role of vagueness as regards the portrayal of the areas that provide water for particular aquifers. For that purpose, concepts of fuzziness in spatial analysis are applied to describe possible extents of recharge areas. In general, any water assessment is based on clearly delineated boundaries. However, in many cases, aquifer recharge areas are not clearly defined due to the nature of the study area. Hence, surfaces indicating a gradual membership to the recharge area of a particular aquifer are used in this investigation. These surfaces, which are based on available qualitative information, visualise a potential range of spatial extension. With regard to water balance calculations, functional relationships in tabular form are derived as well. Based on a regionalisation approach providing spatially distributed recharge rates, the corresponding recharge volume is calculated. Hence, this methodology provides fuzzy input data for water balance calculations. Beyond the portrayal of one singular aquifer recharge area, this approach also supports the complementary consideration of adjacent areas.

  3. Ground-water recharge in Fortymile Wash near Yucca Mountain, Nevada, 1992--1993

    Energy Technology Data Exchange (ETDEWEB)

    Savard, C.S.


    Quantification of the ground-water recharge from streamflow in the Fortymile Wash watershed will contribute to regional ground-water studies. Regional ground-water studies are an important component in the studies evaluating the ground-water flow system as a barrier to the potential migration of radionuclides from the potential underground high-level nuclear waste repository. Knowledge gained in understanding the ground-water recharge mechanisms and pathways in the Pah Canyon area, which is 10 km to the northeast of Yucca Mountain, may transfer to Yucca site specific studies. The current data collection network in Fortymile Canyon does not permit quantification of ground-water recharge, however a qualitative understanding of ground-water recharge was developed from these data.

  4. Vadose zone-attenuated artificial recharge for input to a ground water model. (United States)

    Nichols, William E; Wurstner, Signe K; Eslinger, Paul W


    Accurate representation of artificial recharge is requisite to calibration of a ground water model of an unconfined aquifer for a semiarid or arid site with a vadose zone that imparts significant attenuation of liquid transmission and substantial anthropogenic liquid discharges. Under such circumstances, artificial recharge occurs in response to liquid disposal to the vadose zone in areas that are small relative to the ground water model domain. Natural recharge, in contrast, is spatially variable and occurs over the entire upper boundary of a typical unconfined ground water model. An improved technique for partitioning artificial recharge from simulated total recharge for inclusion in a ground water model is presented. The improved technique is applied using data from the semiarid Hanford Site. From 1944 until the late 1980s, when Hanford's mission was the production of nuclear materials, the quantities of liquid discharged from production facilities to the ground vastly exceeded natural recharge. Nearly all hydraulic head data available for use in calibrating a ground water model at this site were collected during this period or later, when the aquifer was under the diminishing influence of the massive water disposals. The vadose zone is typically 80 to 90 m thick at the Central Plateau where most production facilities were located at this semiarid site, and its attenuation of liquid transmission to the aquifer can be significant. The new technique is shown to improve the representation of artificial recharge and thereby contribute to improvement in the calibration of a site-wide ground water model.

  5. Spatial and temporal variability of ground water recharge in central Australia: a tracer approach. (United States)

    Harrington, Glenn A; Cook, Peter G; Herczeg, Andrew L


    Two environmental tracer methods are applied to the Ti-Tree Basin in central Australia to shed light on the importance of recharge from floodouts of ephemeral rivers in this arid environment. Ground water carbon-14 concentrations from boreholes are used to estimate the average recharge rate over the interval between where the ground water sample first entered the saturated zone and the bore. Environmental chloride concentrations in ground water samples provide estimates of the recharge rate at the exact point in the landscape where the sample entered the saturated zone. The results of the two tracer approaches indicate that recharge rates around one of the rivers and an extensive floodplain are generally higher than rates of diffuse recharge that occurs in areas of lower topographic relief. Ground water 2H/1H and 18O/16O compositions are all depleted in the heavier isotopes (delta2H = -67 per thousand to -50 per thousand; delta18O = -9.2 per thousand to -5.7%o) compared with the long-term, amount-weighted mean isotopic composition of rainfall in the area (delta2H = -33.8 per thousand; delta18O = -6.3 per thousand). This indicates that recharge throughout the basin occurs only after intense rainfall events of at least 150 to 200 mm/month. Finally, a recharge map is developed to highlight the spatial extent of the two recharge mechanisms. Floodout recharge to the freshest ground water (TDS recharge rate of approximately 0.2 mm/year to the remainder of the basin. These findings have important implications for management of the ground water resource.

  6. Quantifying ground water recharge at multiple scales using PRMS and GIS. (United States)

    Cherkauer, Douglas S


    Management of ground water resources requires a method to calculate demonstrably accurate recharge rates at local to regional scales using readily available information bases. Many methods are available to calculate recharge, but most are unable to satisfy all these conditions. A distributed parameter model is shown to meet the stated needs. Such models are input intensive, however, so a procedure to define most inputs from GIS and hydrogeological sources is presented. It simplifies the PRMS calibration observed streamflow hydrographs by reducing degrees of freedom from dozens to four. For seven watersheds (60 to 500 km2), the GIS-aided calibrations have average errors of 5% on recharge and 2% on total streamflow, verifying the accuracy of the process. Recharge is also calculated for 63 local-scale subwatersheds (average size 37 km2). For the study area, calculated recharges average 11 cm/yr. Soil and rock conductivity, porosity, and depth to the water table are shown to be the physical properties which dominate the spatial variability of recharge. The model has been extended to uncalibrated watersheds where GIS and climatic information are known. It reproduces total annual discharge and recharge to within 9% and 10%, respectively, indicating the process can also be used to calculate recharge in ungauged watersheds. It has not been tested outside the study area, however.

  7. Delineating ground water recharge from leaking irrigation canals using water chemistry and isotopes. (United States)

    Harvey, F E; Sibray, S S


    Across the Great Plains irrigation canals are used to transport water to cropland. Many of these canals are unlined, and leakage from them has been the focus of an ongoing legal, economic, and philosophical debate as to whether this lost water should be considered waste or be viewed as a beneficial and reasonable use since it contributes to regional ground water recharge. While historically there has been much speculation about the impact of canal leakage on local ground water, actual data are scarce. This study was launched to investigate the impact of leakage from the Interstate Canal, in the western panhandle of Nebraska, on the hydrology and water quality of the local aquifer using water chemistry and environmental isotopes. Numerous monitoring wells were installed in and around a small wetland area adjacent to the canal, and ground water levels were monitored from June 1992 until January 1995. Using the water level data, the seepage loss from the canal was estimated. In addition, the canal, the monitoring wells, and several nearby stock and irrigation wells were sampled for inorganic and environmental isotope analysis to assess water quality changes, and to determine the extent of recharge resulting from canal leakage. The results of water level monitoring within study wells indicates a rise in local ground water levels occurs seasonally as a result of leakage during periods when the canal is filled. This rise redirects local ground water flow and provides water to nearby wetland ecosystems during the summer months. Chemical and isotopic results were used to delineate canal, surface, and ground water and indicate that leaking canal water recharges both the surface alluvial aquifer and upper portions of the underlying Brule Aquifer. The results of this study indicate that lining the Interstate Canal could lower ground water levels adjacent to the canal, and could adversely impact the local aquifer.

  8. Estimated mean annual natural ground-water recharge in the conterminous United States (United States)

    U.S. Geological Survey, Department of the Interior — This 1-kilometer resolution raster (grid) dataset is an index of mean annual natural ground-water recharge. The dataset was created by multiplying a grid of...

  9. Arsenic mobilization and attenuation by mineral–water interactions: implications for managed aquifer recharge (United States)

    Managed aquifer recharge (MAR) has a potential for addressing deficits in water supplies worldwide. It is also widely used for preventing saltwater intrusion, maintaining the groundwater table, and augmenting ecological stream flows among many beneficial environmental application...

  10. Water reclamation for aquifer recharge at the eight case study sites: a cross case analysis

    CSIR Research Space (South Africa)

    Le Corre, K


    Full Text Available Reclamation Technologies for Safe Managed Aquifer Recharge Water reclamation for aquifer recharge at the eight case study sites: a cross case analysis Le Corre, Kristell, Aharoni, Avi, Cauwenberghs, Johan, Chavez, Alma, Cikurel, Haim,Ayuso Gabella..., Tredoux, Gideon, Wintgens, Thomas, Cheng Xuzhou, Yu, Liang and Zhao, Xuan Abstract: Water scarcity combined with the quality deterioration of freshwater due to the rapid augmentation of population and industrial development is a major concern...

  11. Nocturnal sap flow characteristics and stem water recharge of Acacia mangium

    Institute of Scientific and Technical Information of China (English)

    Hua WANG; Ping ZHAO; Quan WANG; Xian CAI; Ling MA; Xingquan RAO; Xiaoping ZENG


    In this paper,we studied the nocturnal stem water recharge of Acacia mangium. It is helpful to improve the precision of canopy transpiration estimation and canopy stomatal conductance, and to further understand the lag time of canopy transpiration to stem sap flow.In this study,the whole-tree sap flow in an A.mangium forest was measured by using Granier's thermal dissipation probe for over two years in the hilly land of South China. The environmental factors, including relative humidity (RH), precipitation, vapor pressure deficit (VPD), photo-synthetically active radiation (PAR),and air temperature (Ta) were recorded simultaneously. The stem water recharge of A. Mangium was analyzed on both daily and monthly scales. Sap flux density was lower at night than during the day. The time range of nighttime sap flux density was longer in the dry season than in the wet season. The water recharging mainly occurred from sunset to midnight.No significant differences were observed among inter-annual nighttime water recharges. Nighttime water recharge had no significant correlation with environmen-tal factors, but was welt correlated with the diameter at breast height, tree height, and crown size. In the dry season the contribution of nighttime water recharge to total transpiration had significant correlations with daytime transpiration, total transpiration, VPD, PAR and Ta, while in the wet season it was significantly correlated with daily transpiration and total transpiration.

  12. Modeling analysis of ground water recharge potential on alluvial fans using limited data. (United States)

    Munévar, A; Mariño, M A


    A modeling approach is developed to evaluate the potential for artificial recharge on alluvial fans in the Salinas Valley, California, using limited data of soil texture, soil hydraulic properties, and interwell stratigraphy. Promising areas for surface recharge are identified and mapped on a broad-scale using soil surveys, geologic investigations, permeability tests, and seasonal ground water response to rainfall and runoff. Two-dimensional representations of the vadose zone at selected sites are then constructed from drillers'logs and soil material types are estimated. Next, hydraulic properties are assigned to each soil material type by comparing them to laboratory-tested cores of similar soils taken from one site. Finally, water flow through the vadose zone is modeled in two dimensions at seven sites using a transient, finite-difference, variably saturated flow model. Average infiltration rates range from 0.84 to 1.54 cm/hr and recharge efficiency, the percentage of infiltrated water that reaches the water table, varies from 51% to 79%. Infiltration rates and recharge efficiency are found to be relatively insensitive to recharge basin ponding depth due to the thickness of the vadose zones modeled (31 to 84 m). The impact of artificial recharge on the Salinas Valley ground water basin is investigated by simulating the regional ground water response to surface spreading and streamflow augmentation with a recently calibrated, finite-element, ground water-surface water model for the basin. It was determined that a combined approach of surface recharge and streamflow augmentation significantly reduces the state of ground water overdraft and, to a lesser extent, reduces the rate of sea water intrusion.

  13. Environmental isotopes as indicators for ground water recharge to fractured granite. (United States)

    Ofterdinger, U S; Balderer, W; Loew, S; Renard, P


    To assess the contribution of accumulated winter precipitation and glacial meltwater to the recharge of deep ground water flow systems in fracture crystalline rocks, measurements of environmental isotope ratios, hydrochemical composition, and in situ parameters of ground water were performed in a deep tunnel. The measurements demonstrate the significance of these ground water recharge components for deep ground water flow systems in fractured granites of a high alpine catchment in the Central Alps, Switzerland. Hydrochemical and in situ parameters, as well as delta(18)O in ground water samples collected in the tunnel, show only small temporal variations. The precipitation record of delta(18)O shows seasonal variations of approximately 14% and a decrease of 0.23% +/- 0.03% per 100 m elevation gain. delta(2)H and delta(18)O in precipitation are well correlated and plot close to the meteoric water line, as well as delta(2)H and delta(18)O in ground water samples, reflecting the meteoric origin of the latter. The depletion of 18O in ground water compared to 18O content in precipitation during the ground water recharge period indicates significant contributions from accumulated depleted winter precipitation to ground water recharge. The hydrochemical composition of the encountered ground water, Na-Ca-HCO3-SO4(-F), reflects an evolution of the ground water along the flowpath through the granite body. Observed tritium concentrations in ground water range from 2.6 to 16.6 TU, with the lowest values associated with a local negative temperature anomaly and anomalous depleted 18O in ground water. This demonstrates the effect of local ground water recharge from meltwater of submodern glacial ice. Such localized recharge from glaciated areas occurs along preferential flowpaths within the granite body that are mainly controlled by observed hydraulic active shear fractures and cataclastic faults.

  14. A water-budget model and estimates of groundwater recharge for Guam (United States)

    Johnson, Adam G.


    On Guam, demand for groundwater tripled from the early 1970s to 2010. The demand for groundwater is anticipated to further increase in the near future because of population growth and a proposed military relocation to Guam. Uncertainty regarding the availability of groundwater resources to support the increased demand has prompted an investigation of groundwater recharge on Guam using the most current data and accepted methods. For this investigation, a daily water-budget model was developed and used to estimate mean recharge for various land-cover and rainfall conditions. Recharge was also estimated for part of the island using the chloride mass-balance method. Using the daily water-budget model, estimated mean annual recharge on Guam is 394.1 million gallons per day, which is 39 percent of mean annual rainfall (999.0 million gallons per day). Although minor in comparison to rainfall on the island, water inflows from water-main leakage, septic-system leachate, and stormwater runoff may be several times greater than rainfall at areas that receive these inflows. Recharge is highest in areas that are underlain by limestone, where recharge is typically between 40 and 60 percent of total water inflow. Recharge is relatively high in areas that receive stormwater runoff from storm-drain systems, but is relatively low in urbanized areas where stormwater runoff is routed to the ocean or to other areas. In most of the volcanic uplands in southern Guam where runoff is substantial, recharge is less than 30 percent of total water inflow. The water-budget model in this study differs from all previous water-budget investigations on Guam by directly accounting for canopy evaporation in forested areas, quantifying the evapotranspiration rate of each land-cover type, and accounting for evaporation from impervious areas. For the northern groundwater subbasins defined in Camp, Dresser & McKee Inc. (1982), mean annual baseline recharge computed in this study is 159.1 million gallons

  15. Policy Preferences about Managed Aquifer Recharge for Securing Sustainable Water Supply to Chennai City, India


    Norbert Brunner; Markus Starkl; Ponnusamy Sakthivel; Lakshmanan Elango; Subbaiah Amirthalingam; Chinniyampalayam E. Pratap; Munuswamy Thirunavukkarasu; Sundaram Parimalarenganayaki


    The objective of this study is to bring out the policy changes with respect to managed aquifer recharge (focusing on infiltration ponds), which in the view of relevant stakeholders may ease the problem of groundwater depletion in the context of Chennai City; Tamil Nadu; India. Groundwater is needed for the drinking water security of Chennai and overexploitation has resulted in depletion and seawater intrusion. Current policies at the municipal; state and national level all support recharge of...

  16. Effects of Soil and Water Conservation Measures on Groundwater Levels and Recharge

    Directory of Open Access Journals (Sweden)

    Hong Wang


    Full Text Available Measures of soil and water conservation (SWC could affect the hydrological process. The impacts of typical measures on groundwater recharge, levels and flow were analyzed based on simulated rainfall experiments and a groundwater model. The three-dimensional finite-difference groundwater flow model (MODFLOW was calibrated and verified for bare slope, grassland and straw mulching scenarios based on the experiments. The results of the verification in groundwater balance, levels, runoff and flow field all showed that MODFLOW could be applied to study the impact of SWC measures on groundwater. Meanwhile, the results showed the recharge rate (α and specific yield of the three soil layers (Sy1, Sy2 and Sy3 were the most sensitive parameters to the change in the underlying surface. Then, the impacts of the SWC measures’ construction and destruction on the groundwater regime were studied. The results indicated the measures could strengthen groundwater recharge. The amounts of groundwater recharge, runoff and level were on the order of straw mulching > grassland > bare slope. When the underlying surface was converted from grass and mulching to bare slope, the recharge decreased by 42.2% and 39.1%. It was concluded that SWC measure construction would increase groundwater recharge and the measure destruction would decrease recharge.

  17. Water balance-based estimation of groundwater recharge in the Lake Chad Basin (United States)

    Babamaaji, R. A.; Lee, J.


    Lake Chad Basin (LCB) has experienced drastic changes of land cover and poor water management practices during the last 50 years. The successive droughts in the 1970s and 1980s resulted in the shortage of surface water and groundwater resources. This problem of drought and shortage of water has a devastating implication on the natural resources of the Basin with great consequence on food security, poverty reduction and quality of life of the inhabitants in the LCB. Therefore, understanding the change of land use and its characteristics must be a first step to find how such changes disturb the water cycle especially the groundwater in the LCB. The abundance of groundwater is affected by the climate change through the interaction with surface water, such as lakes and rivers, and vertical recharge through an infiltration process. Quantifying the impact of climate change on the groundwater resource requires not only reliable forecasting of changes in the major climatic variables, but also accurate estimation of groundwater recharge. Spatial variations in the land use/land cover, soil texture, topographic slope, and meteorological conditions should be accounted for in the recharge estimation. In this study, we employed a spatially distributed water balance model WetSpass to simulate a long-term average change of groundwater recharge in the LCB of Africa. WetSpass is a water balance-based model to estimate seasonal average spatial distribution of surface runoff, evapotranspiration, and groundwater recharge. The model is especially suitable for studying the effect of land use/land cover change on the water regime in the LCB. The present study describes the concept of the model and its application to the development of recharge map of the LCB.

  18. Can basin-scale recharge be estimated reasonably with water-balance models? (United States)

    Faust, A.E.; Ferre, T. P. A.; Schaap, M.G.; Hinnell, A.C.; Brown, Gordon E.


    We examine in-place recharge as an example of the complex, basin-scale hydrologic processes that are being represented with simplified numerical models. The rate and distribution of recharge depend on local meteorological conditions and hydrogeologic properties. The pattern of recharge is defined predominantly by the distribution of net precipitation (precipitation less evapotranspiration), but different pedotransfer functions (PTFs) predict different fractions of precipitation that become in-place recharge at a given location. At any single location, these differences can often be explained on the basis of the PTF characteristics, but because of the complex averaging that occurs across a basin, the combined effects of meteorological variation and soil textural variation on the basin-wide recharge rates cannot be predicted on the basis of the characteristics of different PTFs. In fact, we show that the same basin-scale numerical model, using identical inputs and modeling options, can produce almost an order of magnitude variation in predicted basin total recharge depending on the choice of PTF. This suggests that sensitivity analyses should be performed on the choice of constitutive relationship (e.g., PTF) when assessing the predictive capability of basin-scale hydrologic models. ?? Soil Science Society of America.

  19. Nitrate reduction during ground-water recharge, Southern High Plains, Texas (United States)

    Fryar, Alan E.; Macko, Stephen A.; Mullican, William F., III; Romanak, Katherine D.; Bennett, Philip C.


    In arid and semi-arid environments, artificial recharge or reuse of wastewater may be desirable for water conservation, but NO 3- contamination of underlying aquifers can result. On the semi-arid Southern High Plains (USA), industrial wastewater, sewage, and feedlot runoff have been retained in dozens of playas, depressions that focus recharge to the regionally important High Plains (Ogallala) aquifer. Analyses of ground water, playa-basin core extracts, and soil gas in an 860-km 2 area of Texas suggest that reduction during recharge limits NO 3- loading to ground water. Tritium and Cl - concentrations in ground water corroborate prior findings of focused recharge through playas and ditches. Typical δ15N values in ground water (>12.5‰) and correlations between δ15N and ln CNO -3-N suggest denitrification, but O 2 concentrations ≥3.24 mg l -1 indicate that NO 3- reduction in ground water is unlikely. The presence of denitrifying and NO 3--respiring bacteria in cores, typical soil-gas δ15N values water can still exceed drinking-water standards, as observed in the vicinity of one playa that received wastewater. Therefore, continued ground-water monitoring in the vicinity of other such basins is warranted.

  20. Persistent Urban Impacts on Surface Water Quality Mediated by Stormwater Recharge (United States)

    Gabor, R. S.; Brooks, P. D.; Neilson, B. T.; Bowen, G. J.; Jameel, M. Y.; Hall, S. J.; Eiriksson, D.; Millington, M. R.; Gelderloos, A.


    rivers in the Wasatch Front and other alluvial systems, we can quantify how characteristics such as discharge patterns and land-use determine alluvial recharge controls on surface water quality.

  1. Rocks, Clays, Water, and Salts: Highly Durable, Infinitely Rechargeable, Eminently Controllable Thermal Batteries for Buildings

    Directory of Open Access Journals (Sweden)

    Alan W. Rempel


    Full Text Available Materials that store the energy of warm days, to return that heat during cool nights, have been fundamental to vernacular building since ancient times. Although building with thermally rechargeable materials became a niche pursuit with the advent of fossil fuel-based heating and cooling, energy and climate change concerns have sparked new enthusiasm for these substances of high heat capacity and moderate thermal conductivity: stone, adobe, rammed earth, brick, water, concrete, and more recently, phase-change materials. While broadly similar, these substances absorb and release heat in unique patterns characteristic of their mineralogies, densities, fluidities, emissivities, and latent heats of fusion. Current architectural practice, however, shows little awareness of these differences and the resulting potential to match materials to desired thermal performance. This investigation explores that potential, illustrating the correspondence between physical parameters and thermal storage-and-release patterns in direct-, indirect-, and isolated-gain passive solar configurations. Focusing on heating applications, results demonstrate the superiority of water walls for daytime warmth, the tunability of granite and concrete for evening warmth, and the exceptional ability of phase-change materials to sustain near-constant heat delivery throughout the night.

  2. Factors influencing ground-water recharge in the eastern United States (United States)

    Nolan, B.T.; Healy, R.W.; Taber, P.E.; Perkins, K.; Hitt, K.J.; Wolock, D.M.


    Ground-water recharge estimates for selected locations in the eastern half of the United States were obtained by Darcian and chloride-tracer methods and compared using statistical analyses. Recharge estimates derived from unsaturated-zone (RUZC) and saturated-zone (RSZC) chloride mass balance methods are less variable (interquartile ranges or IQRs are 9.5 and 16.1 cm/yr, respectively) and more strongly correlated with climatic, hydrologic, land use, and sediment variables than Darcian estimates (IQR = 22.8 cm/yr). The unit-gradient Darcian estimates are a nonlinear function of moisture content and also reflect the uncertainty of pedotransfer functions used to estimate hydraulic parameters. Significance level is 0.3. Estimates of RSZC were evaluated using analysis of variance, multiple comparison tests, and an exploratory nonlinear regression (NLR) model. Recharge generally is greater in coastal plain surficial aquifers, fractured crystalline rocks, and carbonate rocks, or in areas with high sand content. Westernmost portions of the study area have low recharge, receive somewhat less precipitation, and contain fine-grained sediment. The NLR model simulates water input to the land surface followed by transport to ground water, depending on factors that either promote or inhibit water infiltration. The model explains a moderate amount of variation in the data set (coefficient of determination = 0.61). Model sensitivity analysis indicates that mean annual runoff, air temperature, and precipitation, and an index of ground-water exfiltration potential most influence estimates of recharge at sampled sites in the region. Soil characteristics and land use have less influence on the recharge estimates, but nonetheless are significant in the NLR model. ?? 2006 Elsevier B.V. All rights reserved.

  3. Water Banks: Using Managed Aquifer Recharge to Meet Water Policy Objectives

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    Sharon B. Megdal


    Full Text Available Innovation born of necessity to secure water for the U.S. state of Arizona has yielded a model of water banking that serves as an international prototype for effective use of aquifers for drought and emergency supplies. If understood and adapted to local hydrogeological and water supply and demand conditions, this could provide a highly effective solution for water security elsewhere. Arizona is a semi-arid state in the southwestern United States that has growing water demands, significant groundwater overdraft, and surface water supplies with diminishing reliability. In response, Arizona has developed an institutional and regulatory framework that has allowed large-scale implementation of managed aquifer recharge in the state’s deep alluvial groundwater basins. The most ambitious recharge activities involve the storage of Colorado River water that is delivered through the Central Arizona Project (CAP. The CAP system delivers more than 1850 million cubic meters (MCM per year to Arizona’s two largest metropolitan areas, Phoenix and Tucson, along with agricultural users and sovereign Native American Nations, but the CAP supply has junior priority and is subject to reduction during declared shortages on the Colorado River. In the mid-1980s the State of Arizona established a framework for water storage and recovery; and in 1996 the Arizona Water Banking Authority was created to mitigate the impacts of Colorado River shortages; to create water management benefits; and to allow interstate storage. The Banking Authority has stored more than 4718 MCM of CAP water; including more than 740 MCM for the neighboring state of Nevada. The Nevada storage was made possible through a series of interrelated agreements involving regional water agencies and the federal government. The stored water will be recovered within Arizona; allowing Nevada to divert an equal amount of Colorado River water from Lake Mead; which is upstream of CAP’s point of diversion

  4. Solar-rechargeable battery based on photoelectrochemical water oxidation: Solar water battery (United States)

    Kim, Gonu; Oh, Misol; Park, Yiseul


    As an alternative to the photoelectrochemical water splitting for use in the fuel cells used to generate electrical power, this study set out to develop a solar energy rechargeable battery system based on photoelectrochemical water oxidation. We refer to this design as a “solar water battery”. The solar water battery integrates a photoelectrochemical cell and battery into a single device. It uses a water oxidation reaction to simultaneously convert and store solar energy. With the solar water battery, light striking the photoelectrode causes the water to be photo-oxidized, thus charging the battery. During the discharge process, the solar water battery reduces oxygen to water with a high coulombic efficiency (>90%) and a high average output voltage (0.6 V). Because the reduction potential of oxygen is more positive [E0 (O2/H2O) = 1.23 V vs. NHE] than common catholytes (e.g., iodide, sulfur), a high discharge voltage is produced. The solar water battery also exhibits a superior storage ability, maintaining 99% of its specific discharge capacitance after 10 h of storage, without any evidence of self-discharge. The optimization of the cell design and configuration, taking the presence of oxygen in the cell into account, was critical to achieving an efficient photocharge/discharge.

  5. Solar-rechargeable battery based on photoelectrochemical water oxidation: Solar water battery. (United States)

    Kim, Gonu; Oh, Misol; Park, Yiseul


    As an alternative to the photoelectrochemical water splitting for use in the fuel cells used to generate electrical power, this study set out to develop a solar energy rechargeable battery system based on photoelectrochemical water oxidation. We refer to this design as a "solar water battery". The solar water battery integrates a photoelectrochemical cell and battery into a single device. It uses a water oxidation reaction to simultaneously convert and store solar energy. With the solar water battery, light striking the photoelectrode causes the water to be photo-oxidized, thus charging the battery. During the discharge process, the solar water battery reduces oxygen to water with a high coulombic efficiency (>90%) and a high average output voltage (0.6 V). Because the reduction potential of oxygen is more positive [E(0) (O2/H2O) = 1.23 V vs. NHE] than common catholytes (e.g., iodide, sulfur), a high discharge voltage is produced. The solar water battery also exhibits a superior storage ability, maintaining 99% of its specific discharge capacitance after 10 h of storage, without any evidence of self-discharge. The optimization of the cell design and configuration, taking the presence of oxygen in the cell into account, was critical to achieving an efficient photocharge/discharge.

  6. Water Chemistry Impacts on Arsenic Mobilization from Arsenopyrite Dissolution and Secondary Mineral Precipitation: Implications for Managed Aquifer Recharge (United States)

    Managed Aquifer Recharge (MAR) is one water reuse technique with the potential to meet growing water demands. However, MAR sites have encountered arsenic remobilization resulting from recharge operations. To combat this challenge, it is important to identify the mechanism of arse...

  7. Distinguishing sources of ground water recharge by using delta2H and delta18O. (United States)

    Blasch, Kyle W; Bryson, Jeannie R


    Stable isotope values of hydrogen and oxygen from precipitation and ground water samples were compared by using a volumetrically based mixing equation and stable isotope gradient to estimate the season and location of recharge in four basins. Stable isotopes were sampled at 11 precipitation sites of differing elevation during a 2-year period to quantify seasonal stable isotope contributions as a function of elevation. Supplemental stable isotope data collected by the International Atomic Energy Association during a 14-year period were used to reduce annual variability of the mean seasonal stable isotope data. The stable isotope elevation relationships and local precipitation elevation relationships were combined by using a digital elevation model to calculate the total volumetric contribution of water and stable isotope values as a function of elevation within the basins. The results of these precipitation calculations were compared to measured ground water stable isotope values at the major discharge points near the terminus of the basins. Volumetric precipitation contributions to recharge were adjusted to isolate contributing elevations. This procedure provides an improved representation of recharge contributions within the basins over conventional stable isotope methods. Stable isotope values from wells and springs at the terminus of each basin were used to infer the elevations of precipitation important for recharge of the regional ground water flow system. Ancillary climatic, geologic, and stable isotope values were used to further constrain the location where precipitation is entering the ground water flow system.

  8. Effects of experimental passive artificial recharge of treated surface water on water quality in the Equus Beds Aquifer, 2009-2010 (United States)

    Garinger, Linda Pickett; King, Aaron S.; Ziegler, Andrew C.


    Declining water levels and concerns about the migration of a known saltwater plume upgradient from public supply wells prompted the City of Wichita to investigate the feasibility of using artificial recharge to replenish the water supply in the Equus Beds aquifer. After preliminary testing, the City of Wichita began Phase I of the Equus Beds Aquifer Storage and Recovery Project in 2006. In 2009, the City of Wichita installed an experimental passive gravity recharge well and trench system to increase artificial recharge at Recharge Basin 1, one of the six Phase ? recharge sites.

  9. Artificial groundwater recharge as integral part of a water resources system in a humid environment (United States)

    Kupfersberger, Hans; Stadler, Hermann


    In Graz, Austria, artificial groundwater recharge has been operated as an integral part of the drinking water supply system for more than thirty years. About 180 l/s of high quality water from pristine creeks (i.e. no pre-treatment necessary) are infiltrated via sand and lawn basins and infiltration trenches into two phreatic aquifers to sustain the extraction of approximately 400 l/s. The remaining third of drinking water for roughly 300.000 people is provided by a remote supply line from the East alpine karst region Hochschwab. By this threefold model the water supply system is less vulnerable to external conditions. In the early 1980's the infiltration devices were also designed as a hydraulic barrier against riverbank infiltration from the river Mur, which at that time showed seriously impaired water quality due to upstream paper mills. This resulted into high iron and manganese groundwater concentrations which lead to clogging of the pumping wells. These problems have been eliminated in the meantime due to the onsite purification of paper mill effluents and the construction of many waste water treatment plants. The recharge system has recently been thoroughly examined to optimize the operation of groundwater recharge and to provide a basis for further extension. The investigations included (i) field experiments and laboratory analyses to improve the trade off between infiltration rate and elimination capacities of the sand filter basins' top layer, (ii) numerical groundwater modelling to compute the recovery rate of the recharged water, the composition of the origin of the pumped water, emergency scenarios due to the failure of system parts, the transient capture zones of the withdrawal wells and the coordination of recharge and withdrawal and (iii) development of an online monitoring setup combined with a decision support system to guarantee reliable functioning of the entire structure. Additionally, the depreciation, maintenance and operation costs of the

  10. Policy Preferences about Managed Aquifer Recharge for Securing Sustainable Water Supply to Chennai City, India

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    Norbert Brunner


    Full Text Available The objective of this study is to bring out the policy changes with respect to managed aquifer recharge (focusing on infiltration ponds, which in the view of relevant stakeholders may ease the problem of groundwater depletion in the context of Chennai City; Tamil Nadu; India. Groundwater is needed for the drinking water security of Chennai and overexploitation has resulted in depletion and seawater intrusion. Current policies at the municipal; state and national level all support recharge of groundwater and rainwater harvesting to counter groundwater depletion. However, despite such favorable policies, the legal framework and the administrative praxis do not support systematic approaches towards managed aquifer recharge in the periphery of Chennai. The present study confirms this, considering the mandates of governmental key-actors and a survey of the preferences and motives of stakeholder representatives. There are about 25 stakeholder groups with interests in groundwater issues, but they lack a common vision. For example, conflicting interest of stakeholders may hinder implementation of certain types of managed aquifer recharge methods. To overcome this problem, most stakeholders support the idea to establish an authority in the state for licensing groundwater extraction and overseeing managed aquifer recharge.

  11. Multivariate indications between environment and ground water recharge in a sedimentary drainage basin in northwestern China (United States)

    Zhu, Bingqi; Wang, Xunming; Rioual, Patrick


    A paucity of studies on the interaction between environment and ground water recharge severely restricts the ability of people to assess future water resources under changing environment. In this study, an effort to explore the relationship between the arid environment and ground water recharge was carried out using multivariate statistical techniques in a sedimentary drainage basin (the Jungar) in northwestern China. Hierarchical cluster analysis (HCA) and principal components analysis (PCA) were performed based on hydrogeochemical data to assess the ground water recharge and its governing factors. Observation of the HCA and PCA analytical results revealed a division of seven clusters (C1 to C7) and three principal components (PC1 to PC3), which explained 59.6%, 16.6% and 10.9% of the variance, respectively, and thus, accounted for the majority of the total variance in the original dataset. Based on these Q-mode HCA clusters and R-mode PAC scores, dominant environmental processes influencing recharge regimes were identified, i.e., geogenic, geomorphoclimatic, and anthropogenic, which separated the recharge regimes into four zones (Zone I to Zone IV). Zones I and II (C4 + C1) were associated to ;elevated hydroclimate degree; coupled to ;low salinity;. Zone III (C2 + C3) was associated to ;moderately elevated salinity; and evidently ;elevated contamination; but coupled to ;low hydroclimate degree;. Zone IV (C5 + C6 + C7) was associated mainly to ;elevated salinity; coupled to ;low or inverse hydroclimate degree;. It revealed that the geogenic processes are more significant (60%) than the geomorphoclimatic (17%) and anthropogenic (11%) processes. As a result, the overall recharge process is rather heterogeneous and is strongly environment dominated in the Jungar drainage system. Compared with other watersheds in arid environment, a distinctive feature of the Jungar waters is that they are affected by a combination of natural and non-natural events, rather than

  12. Estimating ground water recharge using flow models of perched karstic aquifers. (United States)

    Weiss, Menachem; Gvirtzman, Haim


    The fraction of rain that is annually recharged to ground water is a function of the transient quantities of precipitation (wet vs. dry years) as well as other meteorological and geologic factors, and thus it is very difficult to estimate. In this study, we have used long records (20 to 30 years) of precipitation and spring discharge to reconstruct the transient character of yearly recharge. These data sets were used to calibrate numerical ground water flow models on the less than 3 km(2) scale for four separate perched karstic aquifers in the Judean and Samarian Mountains of Israel. The stratification and karstic character of the local carbonate rock aquifers cause ground water to flow through discrete dissolution channels and to discharge at isolated springs. An innovative, dual-porosity approach was used where a finite-difference solution simulates flow in the rock matrix, while the karstic channels are simulated using computationally simple drains. Perched conditions are also simulated innovatively using MODFLOW by treating the bottom unsaturated layer as if it is saturated, but by assuming zero pressure head throughout the "unsaturated" layer. Best fitting between measured and computed spring hydrograph data has allowed us to develop a set of empirical functions relating measured precipitation to recharge to the aquifer. The generic methodology presented gives insight into the suspected changes in aquifer recharge rates between particularly wet or dry years.

  13. Recharging California's Groundwater: Crop Suitability and Surface Water Availability for Agricultural Groundwater Banking (United States)

    Dahlke, H. E.; Kocis, T. N.; Brown, A.


    Groundwater banking, the intentional recharge of groundwater from surface water for storage and recovery, is an important conjunctive use strategy for water management in California (CA). A largely unexplored approach to groundwater banking, agricultural groundwater banking (ag-GB), utilizes flood flows and agricultural lands (alfalfa/pasture) for recharging groundwater. Understanding soil suitability for ag-GB, crop health and flooding tolerance, leaching of soil nitrate and salts, the availability of surface water for recharge, and the economic costs and benefits of ag-GB is fundamental to assessing the feasibility of local-scale implementation of ag-GB. The study presented here considers both the availability of excess streamflow (e.g., the magnitude, frequency, timing, and duration of winter flood flow) for ag-GB and the risks and benefits associated with using alfalfa fields as spreading grounds for ag-GB. The availability of surface water for winter (Nov to Apr) ag-GB were estimated based on daily streamflow records for 93 stream gauges within the Central Valley, CA. Analysis focused on high-magnitude (>90thpercentile) flows because most lower flows are likely legally allocated in CA. Results based >50 years of data indicate that an average winter/spring (Nov. - Apr.) in the Sacramento River Basin could provide 7 million acre-feet (AF) (8.6 km3) of water for ag-GB from flows above the 90th percentile. These flows originate from few storm events (5-7 events) and occur on average for 25-30 days between November and April. Wintertime on-farm recharge experiments were conducted on a 9-yr old, 15-acre alfalfa field in the Scott Valley, CA, where 135 AF and 107 AF of water were recharged during the winters of 2015 and 2016, respectively. Biomass data collected indicates that pulsed application of 6-10 ft of water on dormant alfalfa results in minimal yield loss (0.5 ton/acre reduction), short-duration saturated conditions in the root-zone, and high recharge

  14. Salinization of a fresh palaeo-ground water resource by enhanced recharge. (United States)

    Leaney, F W; Herczeg, A L; Walker, G R


    Deterioration of fresh ground water resources caused by salinization is a growing issue in many arid and semi-arid parts of the world. We discuss here the incipient salinization of a 10(4) km2 area of fresh ground water (Ground water 14C concentrations and unsaturated zone Cl soil water inventories indicate that the low salinity ground water originated mainly from palaeo-recharge during wet climatic periods more than 20,000 years ago. However, much of the soil water in the 20 to 60 m thick unsaturated zone throughout the area is generally saline (>15,000 mg/L) because of relatively high evapotranspiration during the predominantly semiarid climate of the last 20,000 years. Widespread clearing of native vegetation over the last 100 years and replacement with crops and pastures leads to enhancement of recharge rates that progressively displace the saline soil-water from the unsaturated zone into the ground water. To quantify the impact of this new hydrologic regime, a one-dimensional model that simulates projected ground water salinities as a function of depth to ground water, recharge rates, and soil water salt inventory was developed. Results from the model suggest that, in some areas, the ground water salinity within the top 10 m of the water table is likely to increase by a factor of 2 to 6 during the next 100 years. Ground water quality will therefore potentially degrade beyond the point of usefulness well before extraction of the ground water exhausts the resource.

  15. Application Of Water Table Fluctuation Method To Quantify Spatial Groundwater Recharge Witidn The Southern Slope Of Merapi Volcano, Indonesia

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    Tjahyo Nugroho Adji


    that results in groundwater recharge characteristic. The volcanic slope unit (above 600 m as! has the lowest water table fluctuation indicates the resistant comportment to the annual rainfall. Ihis unit is characterized by the relatively high magnitude of recharge of approximately 4270 mm/year.

  16. Water Supply Source Evaluation in Unmanaged Aquifer Recharge Zones: The Mezquital Valley (Mexico Case Study

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    Antonio Hernández-Espriú


    Full Text Available The Mezquital Valley (MV hosts the largest unmanaged aquifer recharge scheme in the world. The metropolitan area of Mexico City discharges ~60 m3/s of raw wastewater into the valley, a substantial share of which infiltrates into the regional aquifer. In this work, we aim to develop a comprehensive approach, adapted from oil and gas reservoir modeling frameworks, to assess water supply sources located downgradient from unmanaged aquifer recharge zones. The methodology is demonstrated through its application to the Mezquital Valley region. Geological, geoelectrical, petrophysical and hydraulic information is combined into a 3D subsurface model and used to evaluate downgradient supply sources. Although hydrogeochemical variables are yet to be assessed, outcomes suggest that the newly-found groundwater sources may provide a long-term solution for water supply. Piezometric analyses based on 25-year records suggest that the MV is close to steady-state conditions. Thus, unmanaged recharge seems to have been regulating the groundwater balance for the last decades. The transition from unmanaged to managed recharge is expected to provide benefits to the MV inhabitants. It will also be likely to generate new uncertainties in relation to aquifer dynamics and downgradient systems.

  17. Hydrologic conditions, recharge, and baseline water quality of the surficial aquifer system at Jekyll Island, Georgia, 2012-13 (United States)

    Gordon, Debbie W.; Torak, Lynn J.


    An increase of groundwater withdrawals from the surficial aquifer system on Jekyll Island, Georgia, prompted an investigation of hydrologic conditions and water quality by the U.S. Geological Survey during October 2012 through December 2013. The study demonstrated the importance of rainfall as the island’s main source of recharge to maintain freshwater resources by replenishing the water table from the effects of hydrologic stresses, primarily evapotranspiration and pumping. Groundwater-flow directions, recharge, and water quality of the water-table zone on the island were investigated by installing 26 shallow wells and three pond staff gages to monitor groundwater levels and water quality in the water-table zone. Climatic data from Brunswick, Georgia, were used to calculate potential maximum recharge to the water-table zone on Jekyll Island. A weather station located on the island provided only precipitation data. Additional meteorological data from the island would enhance potential evapotranspiration estimates for recharge calculations.

  18. Regional estimation of base recharge to ground water using water balance and a base-flow index. (United States)

    Szilagyi, Jozsef; Harvey, F Edwin; Ayers, Jerry F


    Naturally occurring long-term mean annual base recharge to ground water in Nebraska was estimated with the help of a water-balance approach and an objective automated technique for base-flow separation involving minimal parameter-optimization requirements. Base recharge is equal to total recharge minus the amount of evapotranspiration coming directly from ground water. The estimation of evapotranspiration in the water-balance equation avoids the need to specify a contributing drainage area for ground water, which in certain cases may be considerably different from the drainage area for surface runoff. Evapotranspiration was calculated by the WREVAP model at the Solar and Meteorological Surface Observation Network (SAMSON) sites. Long-term mean annual base recharge was derived by determining the product of estimated long-term mean annual runoff (the difference between precipitation and evapotranspiration) and the base-flow index (BFI). The BFI was calculated from discharge data obtained from the U.S. Geological Survey's gauging stations in Nebraska. Mapping was achieved by using geographic information systems (GIS) and geostatistics. This approach is best suited for regional-scale applications. It does not require complex hydrogeologic modeling nor detailed knowledge of soil characteristics, vegetation cover, or land-use practices. Long-term mean annual base recharge rates in excess of 110 mm/year resulted in the extreme eastern part of Nebraska. The western portion of the state expressed rates of only 15 to 20 mm annually, while the Sandhills region of north-central Nebraska was estimated to receive twice as much base recharge (40 to 50 mm/year) as areas south of it.

  19. Potential groundwater recharge for the State of Minnesota using the Soil-Water-Balance model, 1996-2010 (United States)

    Smith, Erik A.; Westenbroek, Stephen M.


    Groundwater recharge is one of the most difficult components of a water budget to ascertain, yet is an important boundary condition necessary for the quantification of water resources. In Minnesota, improved estimates of recharge are necessary because approximately 75 percent of drinking water and 90 percent of agricultural irrigation water in Minnesota are supplied from groundwater. The water that is withdrawn must be supplied by some combination of (1) increased recharge, (2) decreased discharge to streams, lakes, and other surface-water bodies, and (3) removal of water that was stored in the system. Recent pressure on groundwater resources has highlighted the need to provide more accurate recharge estimates for various tools that can assess the sustainability of long-term water use. As part of this effort, the U.S. Geological Survey, in cooperation with the Minnesota Pollution Control Agency, used the Soil-Water-Balance model to calculate gridded estimates of potential groundwater recharge across Minnesota for 1996‒2010 at a 1-kilometer (0.621-mile) resolution. The potential groundwater recharge estimates calculated for Minnesota from the Soil-Water Balance model included gridded values (1-kilometer resolution) of annual mean estimates (that is, the means for individual years from 1996 through 2010) and mean annual estimates (that is, the mean for the 15-year period 1996−2010).

  20. Annotated bibliography on artificial recharge of ground water, 1955-67 (United States)

    Signor, Donald C.; Growitz, Douglas J.; Kam, William


    Artificial ground-water recharge has become more important as water use by agriculture, industry, and municipalities increases. Water management agencies are increasingly interested in potential use of recharge for pollution abatement, waste-water disposal, and re-use and reclamation of locally available supplies. Research projects and theoretical analyses of operational recharge systems show increased scientific emphasis on the practice. Overall ground-water basin management systems generally now contain considerations of artificial recharge, whether by direct or indirect methods. Artificial ground-water recharge is a means of conserving surface runoff for future use in places where it would otherwise be lost, of protecting ground-water basins from salt-water encroachment along coastal areas, and of storing and distributing imported water. The biblio-graphy emphasizes technology; however, annotations of articles on waste-water reclamation, ground-water management and ground-water basin management are included. Subjects closely related to artificial recharge, including colloidal flow through porous media, field or laboratory instrumentation, and waste disposal by deep well injection are included where they specifically relate to potential recharge problems. Where almost the same material has been published in several journals, all references are included on the assumption that some publications may be more readily available to interested persons than others. Other publications, especially those of foreign literature, provided abstracts that were used freely as time limitations precluded obtaining and annotating all materials. Abstracts taken from published sources are noted. These are: "Abstracts of North American Geology," U.S. Department of the Interior, Geological Survey; "Abstracts of Recent Published Material on Foil and Water Conservation," ARS-41 series, Agricultural F.esearch Service, U.S. Department of Agriculture; "Water and1 Water

  1. Water quality of the Little Arkansas River and Equus Beds Aquifer before and concurrent with large-scale artificial recharge, south-central Kansas, 1995-2012 (United States)

    Tappa, Daniel J.; Lanning-Rush, Jennifer L.; Klager, Brian J.; Hansen, Cristi V.; Ziegler, Andrew C.


    The city of Wichita artificially recharged about 1 billion gallons of water into the Equus Beds aquifer during 2007–2012 as part of Phase I recharge of the Artificial Storage and Recovery project. This report, prepared in cooperation by the U.S. Geological Survey and the city of Wichita, Kansas, summarizes Little Arkansas River (source-water for artificial recharge) andEquus Beds aquifer water quality before (1995–2006) and during (2007–2012) Artificial Storage and Recovery Phase I recharge. Additionally, aquifer water-quality distribution maps are presented and water-quality changes associated with Phase I recharge timing are described.

  2. Freshwater lenses as archive of climate, groundwater recharge, and hydrochemical evolution: Insights from depth-specific water isotope analysis and age determination on the island of Langeoog, Germany (United States)

    Houben, Georg J.; Koeniger, Paul; Sültenfuß, Jürgen


    The age stratification of a freshwater lens on the island of Langeoog, Germany, was reconstructed through depth-specific sampling and groundwater dating using the tritium-helium method. The stratification is strongly affected by the land use and resulting differences in recharge rates. Infiltration at the dune tops is significantly lower than in the valleys, due to repellency of the dry sand. Dune valleys contribute up to four times more groundwater recharge per area than other areas. Housing development in dune areas might therefore significantly decrease the available fresh groundwater. The freshwater column shows a distinct increase of stable isotope values with decreasing depths. Hence, the freshwater lens contains a climate archive which reflects changing environmental conditions at the time of recharge. Combined with tritium-helium dating, this pattern could be matched to climate records which show an increase of the temperature at the time of recharge and rainfall rates during the last 50 years. The spatial and temporal developments of water chemistry during the passage through the lens follow a marked pattern from a sodium and chloride-dominated rainwater of low conductivity to a more mineralized sodium bicarbonate water type, caused by dissolution of carbonate shells close to the surface and subsequent ion exchange of calcium for sodium in the deeper parts.

  3. Determination of recharge fraction of injection water in combined abstraction-injection wells using continuous radon monitoring. (United States)

    Lee, Kil Yong; Kim, Yong-Chul; Cho, Soo Young; Kim, Seong Yun; Yoon, Yoon Yeol; Koh, Dong Chan; Ha, Kyucheol; Ko, Kyung-Seok


    The recharge fractions of injection water in combined abstraction-injection wells (AIW) were determined using continuous radon monitoring and radon mass balance model. The recharge system consists of three combined abstraction-injection wells, an observation well, a collection tank, an injection tank, and tubing for heating and transferring used groundwater. Groundwater was abstracted from an AIW and sprayed on the water-curtain heating facility and then the used groundwater was injected into the same AIW well by the recharge system. Radon concentrations of fresh groundwater in the AIWs and of used groundwater in the injection tank were measured continuously using a continuous radon monitoring system. Radon concentrations of fresh groundwater in the AIWs and used groundwater in the injection tank were in the ranges of 10,830-13,530 Bq/m(3) and 1500-5600 Bq/m(3), respectively. A simple radon mass balance model was developed to estimate the recharge fraction of used groundwater in the AIWs. The recharge fraction in the 3 AIWs was in the range of 0.595-0.798. The time series recharge fraction could be obtained using the continuous radon monitoring system with a simple radon mass balance model. The results revealed that the radon mass balance model using continuous radon monitoring was effective for determining the time series recharge fractions in AIWs as well as for characterizing the recharge system. Copyright © 2016 Elsevier Ltd. All rights reserved.

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

    Delin, Geoffrey N.; Risser, Dennis W.


    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.

  5. Evaluation of chloride mass balance of pore water as an indicator of groundwater recharge to the Monterrey Metropolitan Area, Mexico (United States)

    Rosales-Lagarde, Laura; Pasten, Ernesto; Mora, Abrahan; Mahlknecht, Jürgen


    Monterrey Metropolitan Area in Nuevo Leon, Mexico, is the third largest metropolitan area and one of the most important industrial sites of Mexico. Groundwater constitutes 40% of the water supply to this urban area. This supply is under constant stress due to the population increase. The unsaturated zone at six sites along two cross-sections was characterized to evaluate the potential of chloride concentration as an indicator of recharge. The selected sites include the range of topographic elevations, vegetation, and annual precipitation of the study area. In each site, boreholes up to 5 m deep were drilled and soil was sampled every 0.5 m. The grain size of each soil sample was determined and pore water extracted to determine the water content percentage, and the chloride, sulfate and nitrate concentration of the pore water. The undersaturated zone consists of alluvial deposits with an average gravel and sand content greater than 60% for all but one of the sampling sites. The pore water content varies from 0.4 to 25% by weight with a decreasing trend as depth increases in areas with agriculture. Sulfate has the highest anion concentration in the pore waters, ranging from 42 to 45,000 mg/L and no apparent distribution pattern along the soil profile columns. Chloride concentration ranges from 8 to 3600 mg/L with an increase in concentration below 1.5 m depth in all the profiles. Chloride and sulfate concentrations with depth are directly correlated suggesting a common input, possibly dissolution-precipitation of evaporite minerals from nearby outcrops or an anthropogenic input. Hence, it is unlikely that chloride behaves as a conservative ion. As a result, its concentration is not likely to be a good indicator of groundwater recharge. Finally; the nitrate concentration ranges from 2 to 96 mg/L nitrate, without a clear pattern along the soil profiles. Low concentration of nitrate in the soil profiles below agricultural areas may suggest denitrification as suggested

  6. Hydrologic effects of artificial-recharge experiments with reclaimed water at East Meadow, Long Island, New York (United States)

    Schneider, B.J.; Ku, H.F.; Oaksford, E.T.


    Artificial recharge experiments were conducted at East Meadow, Long Island, New York, from October 1982 through January 1984 to evaluate the degree of groundwater mounding and the chemical effects of artificially replenishing the groundwater system with tertiary-treated wastewater. More than 800 million gallons of treated effluent was returned to the upper glacial aquifer through recharge basins and injection wells in the 15-month period. Reclaimed water was provided by the Cedar Creek advanced wastewater treatment facility in Wantagh, 6 miles away. The chlorinated effluent was pumped to the recharge facility, where it was fed to basins by gravity flow and to injection wells by pumps. Observations during the recharge tests indicate that the two most significant factors in limiting the rate of infiltration through the basin floor were the recharge test duration and quality of reclaimed water. Head buildup in the aquifer beneath the basins ranged from 4.3 to 6.7 ft, depending on the quantity and duration of water application. Head buildup near the injection wells within the aquifer ranged from 0.3 to 1.2 ft. Recharge basins provided a more effective means of moving large quantities of reclaimed water into the aquifer than injection wells. Results of 3-day and 176-day ponding tests in two basins indicate that reclaimed water is relatively unchanged chemically by percolation through the unsaturated zone because: (1) the sand and gravel of the upper glacial aquifer is unreactive, (2) the water moves to the water table rapidly, and (3) the water is highly treated before recharge. The quality of water in the aquifer zones affected by recharge improved, on the whole. Groundwater concentrations of nitrate nitrogen and several low molecular weight hydrocarbons, decreased to well within drinking water standards as a direct result of recharge. Sodium and chloride concentrations increased above background levels as a result of recharge but remained well within drinking water

  7. Predicted water-level and water-quality effects of artificial recharge in the Upper Coachella Valley, California, using a finite-element digital model (United States)

    Swain, Lindsay A.


    From 1936 to 1974, water levels declined more than 100 feet in the Palm Springs area and 60 feet in the Palm Desert area of the upper Coachella Valley, Calif. Water from the Colorado River Aqueduct is presently being recharged to the basin. The dissolved-solids concentration of native ground water in the recharge area is about 210 mg/liter and that of recharge water ranges from 600 to 750 mg/liter. A finite-element model indicates that without recharge the 1974 water levels in the Palm Springs area will decline 200 feet by the year 2000 because of pumpage. If the aquifer is recharged at a rate from about 7 ,500 acre-feet per year in 1973 increasing to 61,200 acre-feet per year in 1990 and thereafter, the water level in the Palm Springs area will decline about 20 feet below the 1974 level by 1991 and recover to the 1974 level by 2000. The solute-transport finite-element model of the recharge area indicates that the artificial recharge plume (bounded by the 300-mg/liter line) will move about 1.1 miles downgradient of the recharge ponds by 1981 and about 4.5 miles from the ponds by 2000. (Woodard-USGS)

  8. Groundwater recharge in suburban areas of Hanoi, Vietnam: effect of decreasing surface-water bodies and land-use change (United States)

    Kuroda, Keisuke; Hayashi, Takeshi; Do, An Thuan; Canh, Vu Duc; Nga, Tran Thi Viet; Funabiki, Ayako; Takizawa, Satoshi


    Over-exploited groundwater is expected to remain the predominant source of domestic water in suburban areas of Hanoi, Vietnam. In order to evaluate the effect on groundwater recharge, of decreasing surface-water bodies and land-use change caused by urbanization, the relevant groundwater systems and recharge pathways must be characterized in detail. To this end, water levels and water quality were monitored for 3 years regarding groundwater and adjacent surface-water bodies, at two typical suburban sites in Hanoi. Stable isotope (δ18O, δD of water) analysis and hydrochemical analysis showed that the water from both aquifers and aquitards, including the groundwater obtained from both the monitoring wells and the neighboring household tubewells, was largely derived from evaporation-affected surface-water bodies (e.g., ponds, irrigated farmlands) rather than from rivers. The water-level monitoring results suggested distinct local-scale flow systems for both a Holocene unconfined aquifer (HUA) and Pleistocene confined aquifer (PCA). That is, in the case of the HUA, lateral recharge through the aquifer from neighboring ponds and/or irrigated farmlands appeared to be dominant, rather than recharge by vertical rainwater infiltration. In the case of the PCA, recharge by the above-lying HUA, through areas where the aquitard separating the two aquifers was relatively thin or nonexistent, was suggested. As the decrease in the local surface-water bodies will likely reduce the groundwater recharge, maintaining and enhancing this recharge (through preservation of the surface-water bodies) is considered as essential for the sustainable use of groundwater in the area.

  9. Accepting managed aquifer recharge of urban storm water reuse: The role of policy-related factors (United States)

    Mankad, Aditi; Walton, Andrea


    A between-groups experimental design examined public acceptance for managed aquifer recharge of storm water for indirect potable and nonpotable reuse; acceptance was based on five policy-related variables (fairness, effectiveness, trust, importance of safety assurances, and importance of communication activities). Results showed that public acceptance (N = 408) for managed aquifer recharge of storm water was higher for nonpotable applications, as was the importance of safety assurances. Analyses of variance also showed that perceptions of fairness and effectiveness were higher for a nonpotable scheme, but not trust. A three-step hierarchical regression (Step 1: age, gender, education, and income; Step 2: type of use; Step 3: fairness, effectiveness, trust, safety assurance, and communication activities) demonstrated that type of storm water use and the policy-related factors accounted for 73% of the variance in acceptance of storm water (R2 = 0.74, adjusted R2 = 0.74, F (10, 397) = 113.919, p related factors were also significant individual predictors of acceptance. The most important predictors were perceptions of trust in water authorities, perceptions of effectiveness, and perceptions of fairness. Interestingly, while safety assurance was important in attitudinal acceptance of managed aquifer recharge based on type of use, safety assurance was not found to be significant predictor of acceptance. This research suggests that policy-makers should look to address matters of greater public importance and drive such as fairness, trust, and effectiveness of storm water programs and advocate these at the forefront of their policies, rather than solely on education campaigns.

  10. Influence of Locally Derived Recharge on the Water Quality and Temperature of Springs in Hot Springs National Park, Arkansas (United States)

    Bell, Richard W.; Hays, Phillip D.


    The hot springs of Hot Springs National Park consist of a mixture of water from two recharge components: a primary hot-water component and a secondary cold-water component. Widespread distribution of fractures enables mixing of the hot- and cold-water components of flow near the discharge area for the springs. Urbanization in the area near the hot springs of Hot Springs National Park has increased the potential for degradation of the quality of surface-water runoff and locally derived ground-water recharge to the hot springs. Previous studies by the U.S. Geological Survey have indicated that water from some cold-water springs and wells in the vicinity of Hot Springs, Arkansas, showed evidence of contamination and that water from locally derived cold-water recharge might contribute 25 percent of the total flow to the hot springs after storms. Water samples were collected during base-flow conditions at nine hot springs and two cold-water springs in September 2000. Nine hot springs and one cold-water spring were resampled in October 2001 after a storm that resulted in a measurable decrease in water temperature in selected hot springs. Water samples were analyzed for a variety of dissolved chemical constituents (nutrients, major ions, trace elements, pesticides, semivolatile compounds, isotopes, and radiochemicals), physical properties, field measurements, and bacteria. Comparison of analyses of samples collected during base-flow conditions from the springs in 2000 and during a storm event in 2001 with the results from earlier studies dating back to the late 1800's indicates that little change in major, minor, and trace constituent chemistry has occurred and that the water continues to be of excellent quality. Water-quality data show distinguishable differences in water chemistry of the springs during base-flow and stormflow conditions, indicating changing input of cold-water recharge relative to hot-water recharge. Silica, total dissolved solids, strontium, barium

  11. Geochemical Information Indicating the Water Recharge to Lakes and Immovable Megadunes in the Badain Jaran Desert

    Institute of Scientific and Technical Information of China (English)

    CHEN Jiansheng; ZHAO Xia; SHENG Xuefeng; WANG Jiyang; GU Weizu; CHEN Liang


    Calc-sinters distributed in the middle of lakes and rhizoconcretions scattered at the slopes of sand dunes were observed during three explorations to the Badain Jaran Desert in the past two years.Wet sands were also found underneath the dry surface sand layers of about 20-50 cm in thickness.The geochemical parameters were measured on minerals and water samples collected from the Badain Jaran Desert and neighboring areas.The results show that the water system in the desert may be recharged from the groundwater originating from the precipitation of the Qilian Mountains and/or the Tibetan Plateau rather than the local rainfalls.

  12. Application of a risk management framework to a drinking water supply augmented by stormwater recharge. (United States)

    Vanderzalm, J L; Page, D W; Dillon, P J


    The Blue Lake is an important water resource for the city of Mount Gambier and the surrounding region, primarily as the drinking water supply source, but also as a tourist attraction. Mount Gambier's stormwater is discharged directly via drainage wells into the unconfined, karstic Gambier Limestone aquifer, which in turn provides the majority of recharge to Blue Lake. Discharge of urban runoff to the aquifer commenced in the 1800s as a means of stormwater management, but is now recognised as contributing to the drinking water supply in Blue Lake. Recently, guidelines for managing the risks associated with water recycling and augmenting drinking water supplies have been developed. This paper examines the organic chemical hazards associated with a stormwater to potable recycling scheme as an example of the current risk management framework.

  13. Aquifer recharge with reclaimed water in the Llobregat Delta. Laboratory batch experiments and field test site. (United States)

    Tobella, J.


    Summary Spain, as most other Mediterranean countries, faces near future water shortages, generalized pollution and loss of water dependent ecosystems. Aquifer recharge represents a promising option to become a source for indirect potable reuse purposes but presence of pathogens as well as organic and inorganic pollutants should be avoided. To this end, understanding the processes of biogeochemical degradation occurring within the aquifer during infiltration is capital. A set of laboratory batch experiments has been assembled in order to assess the behaviour of selected pesticides, drugs, estrogens, surfactant degradation products, biocides and phthalates under different redox conditions. Data collected during laboratory experiments and monitoring activities at the Sant Vicenç dels Horts test site will be used to build and calibrate a numerical model (i) of the physical-chemical-biochemical processes occurring in the batches and (ii) of multicomponent reactive transport in the unsaturated/saturated zone at the test site. Keywords Aquifer recharge, batch experiments, emerging micropollutants, infiltration, numerical model, reclaimed water, redox conditions, Soil Aquifer Treatment (SAT). 1. Introduction In Spain, the Llobregat River and aquifers, which supply water to Barcelona, have been overexploited for years and therefore, suffer from serious damages: the river dries up on summer, riparian vegetation has disappeared and seawater has intruded the aquifer. In a global context, solutions to water stress problems are urgently needed yet must be sustainable, economical and safe. Recent developments of analytical techniques detect the presence of the so-called "emerging" organic micropollutants in water and soils. Such compounds may affect living organisms when occurring in the environment at very low concentrations (microg/l or ng/l). In wastewater and drinking water treatment plants, a remarkable removal of these chemicals from water can be obtained only using

  14. Groundwater surface water interactions and the role of phreatophytes in identifying recharge zones

    Directory of Open Access Journals (Sweden)

    T. S. Ahring


    Full Text Available Groundwater and surface water interactions within riparian corridors impact the distribution of phreatophytes that tap into groundwater stores. The changes in canopy area of phreatophytes over time is related to changes in depth to groundwater, distance from a stream or river, and hydrologic soil group. Remote sensing was used to determine the location of trees with pre-development and post-development aerial photography over the Ogallala Aquifer in the central plains of the United States. It was found that once the depth to groundwater becomes greater than about 3 m, tree populations decrease as depth to water increases. This subsequently limited the extent of phreatophytes to within 700 m of the river. It was also found that phreatophytes have a higher likelihood of growing on hydrologic soil groups with higher saturated hydraulic conductivity. Phreatophytes exist along portions of the Arkansas River corridor where significant decreases in groundwater occurred as long as alluvium exists to create perched conditions where trees survive dry periods. Significant decreases (more that 50% in canopy cover exists along river segments where groundwater declined by more than 10 m, indicating areas with good hydraulic connectivity between surface water and groundwater. Thus, interpretation of changes in phreatophyte distribution using historical and recent aerial photography is important in delineating zones of enhanced recharge where aquifers might be effectively recharged through diversion of surface water runoff.

  15. Groundwater surface water interactions through streambeds and the role of phreatophytes in identifying important recharge zones

    Directory of Open Access Journals (Sweden)

    T. S. Ahring


    Full Text Available Groundwater and surface water interactions within riparian corridors impact the distribution of phreatophytes that tap into groundwater stores. The changes in canopy area of phreatophytes over time is related to changes in depth to groundwater, distance from a stream or river, and hydrologic soil group. Remote sensing was used to determine the location of trees with predevelopment and post-development aerial photography over the Ogallala Aquifer in the central plains of the United States. It was found that once the depth to groundwater becomes greater than about 3 m, tree populations decrease as depth to water increases. This subsequently limited the extent of phreatophytes to within 700 m of the river. It was also found that phreatophytes have a higher likelihood of growing on hydrologic soil groups with higher saturated hydraulic conductivity. Phreatophytes exist along portions of the Arkansas River corridor where significant decreases in groundwater occurred as long as alluvium exists to create perched conditions where trees survive dry periods. Significant decreases (more that 50% in canopy cover exists along river segments where groundwater declined by more than 10 m, indicating areas with good hydraulic connectivity between surface water and groundwater. Thus, interpretation of changes in phreatophyte distribution using historical and recent aerial photophaphy is important in delineating zones of enhanced recharge where aquifers might be effectively recharged through diversion of surface water runoff.

  16. Comparative study of irrigation water use and groundwater recharge under various irrigation schemes in an agricultural region, central Taiwan (United States)

    Chen, Shih-Kai; Jang, Cheng-Shin; Tsai, Cheng-Bin


    The risk of rice production has increased notably due to climate change in Taiwan. To respond to growing agricultural water shortage without affecting normal food production in the future, the application of water-saving irrigation will be a substantial resolution. However, the adoption of water-saving irrigation may result in the reducing of groundwater recharge because continuous flooding in the paddy fields could be regarded as an important source for groundwater recharge. The aim of this study was to evaluate the irrigation water-saving benefit and groundwater recharge deficit when adopting the System of Rice Intensification, known as SRI methodology, in the Choushui River alluvial fan (the largest groundwater pumping and the most important rice-cropping region in central Taiwan). The three-dimensional finite element groundwater model, FEMWATER, was applied to simulate the infiltration process and groundwater recharge under SRI methodology and traditional irrigation schemes including continuous irrigation, and rotational irrigation in two rice-crop periods with hydro-climatic data of 2013. The irrigation water use was then calculated by water balance. The results showed that groundwater recharge amount of SRI methodology was slightly lower than those of traditional irrigation schemes, reduced 3.6% and 1.6% in the first crop period, and reduced 3.2% and 1.6% in the second crop period, compared with continuous irrigation and rotational irrigation, respectively. However, the SRI methodology achieved notably water-saving benefit compared to the disadvantage of reducing the groundwater recharge amount. The field irrigation requirement amount of SRI methodology was significantly lower than those of traditional irrigation schemes, saving 37% and 20% of irrigation water in the first crop period, and saving 53% and 35% in the second crop period, compared with continuous irrigation and rotational irrigation, respectively. Therefore, the amount of groundwater pumping for

  17. Restoration of wadi aquifers by artificial recharge with treated waste water. (United States)

    Missimer, Thomas M; Drewes, Jörg E; Amy, Gary; Maliva, Robert G; Keller, Stephanie


    Fresh water resources within the Kingdom of Saudi Arabia are a rare and precious commodity that must be managed within a context of integrated water management. Wadi aquifers contain a high percentage of the naturally occurring fresh groundwater in the Kingdom. This resource is currently overused and has become depleted or contaminated at many locations. One resource that could be used to restore or enhance the fresh water resources within wadi aquifers is treated municipal waste water (reclaimed water). Each year about 80 percent of the country's treated municipal waste water is discharged to waste without any beneficial use. These discharges not only represent a lost water resource, but also create a number of adverse environmental impacts, such as damage to sensitive nearshore marine environments and creation of high-salinity interior surface water areas. An investigation of the hydrogeology of wadi aquifers in Saudi Arabia revealed that these aquifers can be used to develop aquifer recharge and recovery (ARR) systems that will be able to treat the impaired-quality water, store it until needed, and allow recovery of the water for transmittal to areas in demand. Full-engineered ARR systems can be designed at high capacities within wadi aquifer systems that can operate in concert with the natural role of wadis, while providing the required functions of additional treatment, storage and recovery of reclaimed water, while reducing the need to develop additional, energy-intensive desalination to meet new water supply demands.

  18. Seasonal recharge and mean residence times of soil and epikarst water in a small karst catchment of southwest China. (United States)

    Hu, Ke; Chen, Hongsong; Nie, Yunpeng; Wang, Kelin


    Soil and epikarst play an important role in the hydrological cycle in karst regions. This paper focuses on investigating the seasonal recharge and mean residence time (MRT) of soil water and epikarst water in a small karst catchment of southwest China. The deuterium contents in precipitation, creek, soil baseflow (direct recharge of the saturated soil water to the stream), epikarst spring, and soil waters were monitored weekly for two years, and MRT was calculated by an exponential model (EM) and a dispersion model (DM). The obvious seasonal variation of deuterium in rainfall was buffered in epikarst water, indicating sufficient water mixing. Soil baseflow contained less rainy-season rainwater than epikarst spring discharge, reflecting the retarded effect of soil thickness on rainwater recharge. MRTs of all water bodies were 41-71 weeks, and soils in the depression extended those of shallow groundwater. This demonstrated that the deep soil layer played an important role in karst hydrological processes in the study catchment. The creek was recharged mostly by rainfall through epikarst, indicating its crucial role in water circulation. These results showed epikarst had a strong water-holding capacity and also delayed water contact time with dolomite.

  19. Impacts on groundwater recharge areas of megacity pumping: analysis of potential contamination of Kolkata, India, water supply (United States)

    Sahu, Paulami; Michael, Holly A.; Voss, Clifford I.; Sikdar, Pradip K.


    Water supply to the world's megacities is a problem of quantity and quality that will be a priority in the coming decades. Heavy pumping of groundwater beneath these urban centres, particularly in regions with low natural topographic gradients, such as deltas and floodplains, can fundamentally alter the hydrological system. These changes affect recharge area locations, which may shift closer to the city centre than before development, thereby increasing the potential for contamination. Hydrogeological simulation analysis allows evaluation of the impact on past, present and future pumping for the region of Kolkata, India, on recharge area locations in an aquifer that supplies water to over 13 million people. Relocated recharge areas are compared with known surface contamination sources, with a focus on sustainable management of this urban groundwater resource. The study highlights the impacts of pumping on water sources for long-term development of stressed city aquifers and for future water supply in deltaic and floodplain regions of the world.

  20. Sources of groundwater and characteristics of surface-water recharge at Bell, White, and Suwannee Springs, Florida, 2012–13 (United States)

    Stamm, John F.; McBride, W. Scott


    Discharge from springs in Florida is sourced from aquifers, such as the Upper Floridan aquifer, which is overlain by an upper confining unit that locally can have properties of an aquifer. Water levels in aquifers are affected by several factors, such as precipitation, recharge, and groundwater withdrawals, which in turn can affect discharge from springs. Therefore, identifying groundwater sources and recharge characteristics can be important in assessing how these factors might affect flows and water levels in springs and can be informative in broader applications such as groundwater modeling. Recharge characteristics include the residence time of water at the surface, apparent age of recharge, and recharge water temperature.The groundwater sources and recharge characteristics of three springs that discharge from the banks of the Suwannee River in northern Florida were assessed for this study: Bell Springs, White Springs, and Suwannee Springs. Sources of groundwater were also assessed for a 150-foot-deep well finished within the Upper Floridan aquifer, hereafter referred to as the UFA well. Water samples were collected for geochemical analyses in November 2012 and October 2013 from the three springs and the UFA well. Samples were analyzed for a suite of major ions, dissolved gases, and isotopes of sulfur, strontium, oxygen, and hydrogen. Daily means of water level and specific conductance at White Springs were continuously recorded from October 2012 through December 2013 by the Suwannee River Water Management District. Suwannee River stage at White Springs was computed on the basis of stage at a U.S. Geological Survey streamgage about 2.4 miles upstream. Water levels in two wells, located about 2.5 miles northwest and 13 miles southeast of White Springs, were also used in the analyses.Major ion concentrations were used to differentiate water from the springs and Upper Floridan aquifer into three groups: Bell Springs, UFA well, and White and Suwannee Springs. When

  1. Water infiltration in an aquifer recharge basin affected by temperature and air entrapment

    Directory of Open Access Journals (Sweden)

    Loizeau Sébastien


    Full Text Available Artificial basins are used to recharge groundwater and protect water pumping fields. In these basins, infiltration rates are monitored to detect any decrease in water infiltration in relation with clogging. However, miss-estimations of infiltration rate may result from neglecting the effects of water temperature change and air-entrapment. This study aims to investigate the effect of temperature and air entrapment on water infiltration at the basin scale by conducting successive infiltration cycles in an experimental basin of 11869 m2 in a pumping field at Crepieux-Charmy (Lyon, France. A first experiment, conducted in summer 2011, showed a strong increase in infiltration rate; which was linked to a potential increase in ground water temperature or a potential dissolution of air entrapped at the beginning of the infiltration. A second experiment was conducted in summer, to inject cold water instead of warm water, and also revealed an increase in infiltration rate. This increase was linked to air dissolution in the soil. A final experiment was conducted in spring with no temperature contrast and no entrapped air (soil initially water-saturated, revealing a constant infiltration rate. Modeling and analysis of experiments revealed that air entrapment and cold water temperature in the soil could substantially reduce infiltration rate over the first infiltration cycles, with respective effects of similar magnitude. Clearly, both water temperature change and air entrapment must be considered for an accurate assessment of the infiltration rate in basins.

  2. Comparing potential recharge estimates from three Land Surface Models across the western US (United States)

    Niraula, Rewati; Meixner, Thomas; Ajami, Hoori; Rodell, Matthew; Gochis, David; Castro, Christopher L.


    Groundwater is a major source of water in the western US. However, there are limited recharge estimates in this region due to the complexity of recharge processes and the challenge of direct observations. Land surface Models (LSMs) could be a valuable tool for estimating current recharge and projecting changes due to future climate change. In this study, simulations of three LSMs (Noah, Mosaic and VIC) obtained from the North American Land Data Assimilation System (NLDAS-2) are used to estimate potential recharge in the western US. Modeled recharge was compared with published recharge estimates for several aquifers in the region. Annual recharge to precipitation ratios across the study basins varied from 0.01% to 15% for Mosaic, 3.2% to 42% for Noah, and 6.7% to 31.8% for VIC simulations. Mosaic consistently underestimates recharge across all basins. Noah captures recharge reasonably well in wetter basins, but overestimates it in drier basins. VIC slightly overestimates recharge in drier basins and slightly underestimates it for wetter basins. While the average annual recharge values vary among the models, the models were consistent in identifying high and low recharge areas in the region. Models agree in seasonality of recharge occurring dominantly during the spring across the region. Overall, our results highlight that LSMs have the potential to capture the spatial and temporal patterns as well as seasonality of recharge at large scales. Therefore, LSMs (specifically VIC and Noah) can be used as a tool for estimating future recharge in data limited regions.

  3. Water Use, Ground-Water Recharge and Availability, and Quality of Water in the Greenwich Area, Fairfield County, Connecticut and Westchester County, New York, 2000-2002 (United States)

    Mullaney, John R.


    Ground-water budgets were developed for 32 small basin-based zones in the Greenwich area of southwestern Connecticut, where crystalline-bedrock aquifers supply private wells, to determine the status of residential ground-water consumption relative to rates of ground-water recharge and discharge. Estimated residential ground-water withdrawals for small basins (averaging 1.7 square miles (mi2) ranged from 0 to 0.16 million gallons per day per square mile (Mgal/d/mi2). To develop these budgets, residential ground-water withdrawals were estimated using multiple-linear regression models that relate water use from public water supply to data on residential property characteristics. Average daily water use of households with public water supply ranged from 219 to 1,082 gallons per day (gal/d). A steady-state finite-difference ground-water-flow model was developed to track water budgets, and to estimate optimal values for hydraulic conductivity of the bedrock (0.05 feet per day) and recharge to the overlying till deposits (6.9 inches) using nonlinear regression. Estimated recharge rates to the small basins ranged from 3.6 to 7.5 inches per year (in/yr) and relate to the percentage of the basin underlain by coarse-grained glacial stratified deposits. Recharge was not applied to impervious areas to account for the effects of urbanization. Net residential ground-water consumption was estimated as ground-water withdrawals increased during the growing season, and ranged from 0 to 0.9 in/yr. Long-term average stream base flows simulated by the ground-water-flow model were compared to calculated values of average base flow and low flow to determine if base flow was substantially reduced in any of the basins studied. Three of the 32 basins studied had simulated base flows less than 3 in/yr, as a result of either ground-water withdrawals or reduced recharge due to urbanization. A water-availability criteria of the difference between the 30-day 2-year low flow and the recharge rate

  4. Analysis of confidence in continental-scale groundwater recharge estimates for Africa using a distributed water balance model (United States)

    Mackay, Jonathan; Mansour, Majdi; Bonsor, Helen; Pachocka, Magdalena; Wang, Lei; MacDonald, Alan; Macdonald, David; Bloomfield, John


    There is a growing need for improved access to reliable water in Africa as population and food production increases. Currently approximately 300 million people do not have access to a secure source of safe drinking water. To meet these current and future demands, groundwater will need to be increasingly abstracted; groundwater is more reliable than surface water sources due to its relatively long response time to meteorological stresses and therefore is likely to be a more secure water resource in a more variable climate. Recent studies also quantified the volumes of groundwater potentially available which suggest that, if exploited, groundwater could help to meet the demand for fresh water. However, there is still considerable uncertainty as to how these resources may respond in the future due to changes in groundwater recharge and abstraction. Understanding and quantifying groundwater recharge is vital as it forms a primary indicator of the sustainability of underlying groundwater resources. Computational hydrological models provide a means to do this, but the complexity of recharge processes in Africa mean that these simulations are often highly uncertain. This study aims to evaluate our confidence in simulating groundwater recharge over Africa based on a sensitivity analysis using a distributed hydrological model developed by the British Geological Survey, ZOODRM. The model includes land surface, canopy, river, soil and groundwater components. Each component is able to exchange water and as such, forms a distributed water balance of Africa. The components have been parameterised using available spatial datasets of African vegetation, land-use, soil and hydrogeology while the remaining parameters have been estimated by calibrating the model to available river flow data. Continental-scale gridded precipitation and potential evapotranspiration datasets, based on remotely sensed and ground observations, have been used to force the model. Following calibration, the

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

    NARCIS (Netherlands)

    Nyagwambo, N.L.


    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

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

    NARCIS (Netherlands)

    Nyagwambo, N.L.


    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

  7. MARSOL: Demonstrating Managed Aquifer Recharge as a Solution to Water Scarcity and Drought (United States)

    Schueth, Christoph


    Southern Europe and the Mediterranean region are facing the challenge of managing its water resources under conditions of increasing scarcity and concerns about water quality. Already, the availability of fresh water in sufficient quality and quantity is one of the major factors limiting socio economic development. Innovative water management strategies such as the storage of reclaimed water or excess water from different sources in Managed Aquifer Recharge (MAR) schemes can greatly increase water availability and therefore improve water security. Main objective of the proposed project MARSOL is to demonstrate that MAR is a sound, safe and sustainable strategy that can be applied with great confidence and therefore offering a key approach for tackling water scarcity in Southern Europe. For this, eight field sites were selected that will demonstrate the applicability of MAR using various water sources, ranging from treated wastewater to desalinated seawater, and a variety of technical solutions. Targets are the alleviation of the effect of climate change on water resources, the mitigation of droughts, to countermeasure temporal and spatial misfit of water availability, to sustain agricultural water supply and rural socio-economic development, to combat agricultural related pollutants, to sustain future urban and industrial water supply and to limit seawater intrusion in coastal aquifers. Results of the demonstration sites will be used to develop guidelines for MAR site selection, technical realization, monitoring strategies, and modeling approaches, to offer stakeholders a comprehensive, state of the art and proven toolbox for MAR implementation. Further, the economic and legal aspects of MAR will be analyzed to enable and accelerate market penetration. The MARSOL consortium combines the expertise of consultancies, water suppliers, research institutions, and public authorities, ensuring high practical relevance and market intimacy.

  8. Ground-water recharge in Fortymile Wash near Yucca Mountain, Nevada, 1992-93

    Energy Technology Data Exchange (ETDEWEB)

    Savard, C.S. [Geological Survey, Mercury, NV (United States)


    Ground-water recharge occurred after five separate streamflow event periods in the Pah Canyon area of Fortymile Wash approximately 10 kilometers from Yucca Mountain, Nevada during 1992-93. Ground-water levels rose in two wells, UE-29 a No.1 and UE-29 a No.2, and one neutron-access borehole, UE-29 UZN-91, after each streamflow event period. A maximum rise of 2.9 meters occurred at UE-29 a No.1 thirteen days after the largest streamflow event where depth to water changed from 27.3 to 24.4 meters. Water levels fluctuated 3.89 meters in UE-29 a No.1, 2.92 meters in UE-29 a No.2, and 2.10 meters in UE-29 UZN-91 during the period January, 1992 to September, 1993. During two of the streamflow event periods, one in 1992 and one in 1993, there was flow around the neutron-access borehole located in the Fortymile Wash channel. Three other streamflow event periods were documented in Pah Canyon Wash but the streamflow infiltrated prior to reaching the neutron-access borehole location. Volumetric-water-content profiles were measured periodically in the neutron-access borehole. After the 1992 streamflow event period, water content increased in the upper six meters of the unsaturated zone. After the 1993 streamflow event period, water content increased in the entire unsaturated section, approximately 16 meters thick at the neutron-access borehole. Water levels in the neutron-access borehole rose even when there was no apparent water movement through the unsaturated zone as inferred by changes in the volumetric-water contents. This rise is attributed to ground-water recharge from nearby infiltration of Pah Canyon Wash streamflow. A groundwater mound probably formed beneath Pah Canyon Wash and spread laterally as evidence by larger rises in water levels in UE-29 a No.1 and UE-29 a No.2, which are closer to Pah Canyon Wash than UE-29 UZN-91.

  9. Spatially variable water table recharge and the hillslope hydrologic response: Analytical solutions to the linearized hillslope Boussinesq equation (United States)

    Dralle, David N.; Boisramé, Gabrielle F. S.; Thompson, Sally E.


    The linearized hillslope Boussinesq equation, introduced by Brutsaert (1994), describes the dynamics of saturated, subsurface flow from hillslopes with shallow, unconfined aquifers. In this paper, we use a new analytical technique to solve the linearized hillslope Boussinesq equation to predict water table dynamics and hillslope discharge to channels. The new solutions extend previous analytical treatments of the linearized hillslope Boussinesq equation to account for the impact of spatiotemporal heterogeneity in water table recharge. The results indicate that the spatial character of recharge may significantly alter both steady state subsurface storage characteristics and the transient hillslope hydrologic response, depending strongly on similarity measures of controls on the subsurface flow dynamics. Additionally, we derive new analytical solutions for the linearized hillslope-storage Boussinesq equation and explore the interaction effects of recharge structure and hillslope morphology on water storage and base flow recession characteristics. A theoretical recession analysis, for example, demonstrates that decreasing the relative amount of downslope recharge has a similar effect as increasing hillslope convergence. In general, the theory suggests that recharge heterogeneity can serve to diminish or enhance the hydrologic impacts of hillslope morphology.

  10. Restoration of Wadi Aquifers by Artificial Recharge with Treated Waste Water

    KAUST Repository

    Missimer, Thomas M.


    Fresh water resources within the Kingdom of Saudi Arabia are a rare and precious commodity that must be managed within a context of integrated water management. Wadi aquifers contain a high percentage of the naturally occurring fresh groundwater in the Kingdom. This resource is currently overused and has become depleted or contaminated at many locations. One resource that could be used to restore or enhance the fresh water resources within wadi aquifers is treated municipal waste water (reclaimed water). Each year about 80 percent of the country\\'s treated municipal waste water is discharged to waste without any beneficial use. These discharges not only represent a lost water resource, but also create a number of adverse environmental impacts, such as damage to sensitive nearshore marine environments and creation of high-salinity interior surface water areas. An investigation of the hydrogeology of wadi aquifers in Saudi Arabia revealed that these aquifers can be used to develop aquifer recharge and recovery (ARR) systems that will be able to treat the impaired-quality water, store it until needed, and allow recovery of the water for transmittal to areas in demand. Full-engineered ARR systems can be designed at high capacities within wadi aquifer systems that can operate in concert with the natural role of wadis, while providing the required functions of additional treatment, storage and recovery of reclaimed water, while reducing the need to develop additional, energy-intensive desalination to meet new water supply demands. © 2012, The Author(s). Ground Water © 2012, National Ground Water Association.

  11. Regression Method for Estimating Long-Term Mean Annual Ground-Water Recharge Rates from Base Flow in Pennsylvania (United States)

    Risser, Dennis W.; Thompson, Ronald E.; Stuckey, Marla H.


    A method was developed for making estimates of long-term, mean annual ground-water recharge from streamflow data at 80 streamflow-gaging stations in Pennsylvania. The method relates mean annual base-flow yield derived from the streamflow data (as a proxy for recharge) to the climatic, geologic, hydrologic, and physiographic characteristics of the basins (basin characteristics) by use of a regression equation. Base-flow yield is the base flow of a stream divided by the drainage area of the basin, expressed in inches of water basinwide. Mean annual base-flow yield was computed for the period of available streamflow record at continuous streamflow-gaging stations by use of the computer program PART, which separates base flow from direct runoff on the streamflow hydrograph. Base flow provides a reasonable estimate of recharge for basins where streamflow is mostly unaffected by upstream regulation, diversion, or mining. Twenty-eight basin characteristics were included in the exploratory regression analysis as possible predictors of base-flow yield. Basin characteristics found to be statistically significant predictors of mean annual base-flow yield during 1971-2000 at the 95-percent confidence level were (1) mean annual precipitation, (2) average maximum daily temperature, (3) percentage of sand in the soil, (4) percentage of carbonate bedrock in the basin, and (5) stream channel slope. The equation for predicting recharge was developed using ordinary least-squares regression. The standard error of prediction for the equation on log-transformed data was 9.7 percent, and the coefficient of determination was 0.80. The equation can be used to predict long-term, mean annual recharge rates for ungaged basins, providing that the explanatory basin characteristics can be determined and that the underlying assumption is accepted that base-flow yield derived from PART is a reasonable estimate of ground-water recharge rates. For example, application of the equation for 370

  12. Estimation of natural ground water recharge for the performance assessment of a low-level waste disposal facility at the Hanford Site

    Energy Technology Data Exchange (ETDEWEB)

    Rockhold, M.L.; Fayer, M.J.; Kincaid, C.T.; Gee, G.W.


    In 1994, the Pacific Northwest Laboratory (PNL) initiated the Recharge Task, under the PNL Vitrification Technology Development (PVTD) project, to assist Westinghouse Hanford Company (WHC) in designing and assessing the performance of a low-level waste (LLW) disposal facility for the US Department of Energy (DOE). The Recharge Task was established to address the issue of ground water recharge in and around the LLW facility and throughout the Hanford Site as it affects the unconfined aquifer under the facility. The objectives of this report are to summarize the current knowledge of natural ground water recharge at the Hanford Site and to outline the work that must be completed in order to provide defensible estimates of recharge for use in the performance assessment of this LLW disposal facility. Recharge studies at the Hanford Site indicate that recharge rates are highly variable, ranging from nearly zero to greater than 100 mm/yr depending on precipitation, vegetative cover, and soil types. Coarse-textured soils without plants yielded the greatest recharge. Finer-textured soils, with or without plants, yielded the least. Lysimeters provided accurate, short-term measurements of recharge as well as water-balance data for the soil-atmosphere interface and root zone. Tracers provided estimates of longer-term average recharge rates in undisturbed settings. Numerical models demonstrated the sensitivity of recharge rates to different processes and forecast recharge rates for different conditions. All of these tools (lysimetry, tracers, and numerical models) are considered vital to the development of defensible estimates of natural ground water recharge rates for the performance assessment of a LLW disposal facility at the Hanford Site.

  13. Assessment of water-recharging based on ecological features of riparian forest in the lower reaches of Tarim River

    Institute of Scientific and Technical Information of China (English)

    ZHAO Zhenyong; WANG Ranghui; SUN Hongbo; ZHANG Huizhi


    The occurrence and development of riparian forests which are mainly dominated by mesophytes species relate closely with surface water.Since there is no water discharge to the lower reaches of Tarim River in past 5 decade years, the riparian forests degrade severely. Based on the analyses of the monitored data of Yingsu, Argan and Luobuzhuang in 2002 and 2003, the effect of water-recharging is discussed. The water-recharging project neglects the fact that that it is flooding that controls the process of Populus euphratica colonizing on the bare surface, but focuses on groundwater influence on vegetation. The flooding control deviates inherent laws of riparian forests development, so the natural regeneration of riparian forests is checked.The responsescope of riparian plants on groundwater uplift is extremely narrow, and most riparian communities have not been optimized. No seedlings of dominant species are found in flooding areas because their physio-ecological characteristics are ignored. The vegetation changes in vicinities of stream only reflect the demand of mesophytes species on the shallow groundwater, however, the water-recharging fails to provide suitable habitats for the seedlings establishment of riparian plants. The present water-recharging scheme is difficult to realize vegetation restoration.

  14. Recharge in northern clime calcareous sandy soils: soil water chemical and carbon-14 evolution (United States)

    Reardon, E. J.; Mozeto, A. A.; Fritz, P.


    Chemical analyses were performed on soil water extracted from two cores taken from a sandy calcareous soil near Delhi, Ontario. Calcite saturation is attained within the unsaturated zone over short distances and short periods of time, whereas dolomite undersaturation persists to the groundwater table. The progressive dissolution of dolomite by soil water, within the unsaturated zone, after calcite saturation is reached results in calcite supersaturation. Deposition of iron and manganese oxyhydroxide phases occurs at the carbonate leached/unleached zone boundary. This is a result of soil water neutralization due to carbonate dissolution during infiltration but may also reflect the increased rate of oxidation of dissolved ferrous and manganous ions at higher pH's. The role of bacteria in this process has not been investigated. The depth of the carbonate leached/unleached zone boundary in a calcareous soil has important implications for 14C groundwater dating. The depth of this interface at the study site (-2 m) does not appear to limit 14C diffusion from the root zone to the depth at which carbonate dissolution occurs. Thus, soil water achieves open system isotopic equilibrium with the soil CO 2 gas phase. It is calculated that in soils with similar physical properties to the study soil but with depths of leaching of 5 m or more, complete 14C isotopic equilibration of soil water with soil gas would not occur. Soil water, under these conditions would recharge to the groundwater exhibiting some degree of closed system 14C isotopic evolution.

  15. Characterization of recharge and flow behaviour of different water sources in Gunung Kidul and its impact on water quality based on hydrochemical and physico-chemical monitoring (United States)

    Eiche, Elisabeth; Hochschild, Maren; Haryono, Eko; Neumann, Thomas


    Karst aquifers are important water resources but highly vulnerable due to their heterogeneous and complex characteristics. Various hydrological aspects (recharge, flow behaviour) have to be known in detail to develop a sustainable concept for water collection, distribution and treatment. In the karst area of Gunung Sewu (Java, Indonesia) such a concept was to be implemented within a German-Indonesian joint IWRM project. The basic hydrogeological conditions and water quality aspects were characterized on a regional scale through hydrochemical monitoring of springs, wells, subsurface and surface rivers. More detailed information about the recharge, flow and storage behaviour was obtained from high resolution monitoring of T, EC and discharge in one large underground river system. The water quality is well below any guideline values with regard to inorganic pollutants during dry season. During rainy season, dissolved Al concentrations are frequently above the Indonesian guideline value. Slow matrix flow is the most important recharge component during dry season, thus assuring the year-round water availability in the subsurface karst. During rainy season, quick infiltration of the surface water is a dominant recharge component. Rapid response of discharge, T and EC to heavy rain suggests the presence of point recharge that feeds a highly karstfied conduit system with fast conduit flow and short transit time of water. The strong variations in discharge and hydrochemistry are particularly challenging for technical water usage and treatment facilities. Piston flow is indicated to be the third important flow component and is induced by heavy rainfall.

  16. Recharge contribution to the Guarani Aquifer System estimated from the water balance method in a representative watershed

    Directory of Open Access Journals (Sweden)

    Edson Wendland


    Full Text Available The contribution of recharge to regional groundwater flow systems is essential information required to establish sustainable water resources management. The objective of this work was to determine the groundwater outflow in the Ribeirão da Onça Basin using a water balance model of the saturated soil zone. The basin is located in the outcrop region of the Guarani Aquifer System (GAS. The water balance method involved the determination of direct recharge values, groundwater storage variation and base flow. The direct recharge was determined by the water table fluctuation method (WTF. The base flow was calculated by the hydrograph separation method, which was generated by a rain-flow model supported by biweekly streamflow measurements in the control section. Undisturbed soil samples were collected at depths corresponding to the variation zone of the groundwater level to determine the specific yield of the soil (drainable porosity. Water balances were performed in the saturated zone for the hydrological years from February 2004 to January 2007. The direct recharge ranged from 14.0% to 38.0%, and groundwater outflow from 0.4% to 2.4% of the respective rainfall during the same period.

  17. Precipitation patterns and moisture fluxes in a sandy, tropical environment with a shallow water table (United States)

    Minihane, M. R.; Freyberg, D. L.


    Identifying the dominant mechanisms controlling recharge in shallow sandy soils in tropical climates has received relatively little attention. Given the expansion of coastal fill using marine sands and the growth of coastal populations throughout the tropics, there is a need to better understand the nature of water balances in these settings. We use time series of field observations at a coastal landfill in Singapore coupled with numerical modeling using the Richards' equation to examine the impact of precipitation patterns on soil moisture dynamics, including percolation past the root zone and recharge, in such an environment. A threshold in total precipitation event depth, much more so than peak precipitation intensity, is the strongest event control on recharge. However, shallow antecedent moisture, and therefore the timing between events along with the seasonal depth to water table, also play significant roles in determining recharge amounts. For example, at our field site, precipitation events of less than 3 mm per event yield little to no direct recharge, but for larger events, moisture content changes below the root zone are linearly correlated to the product of the average antecedent moisture content and the total event precipitation. Therefore, water resources planners need to consider identifying threshold precipitation volumes, along with the multiple time scales that capture variability in event antecedent conditions and storm frequency in assessing the role of recharge in coastal water balances in tropical settings.

  18. Effect of urban stormwater runoff on ground water beneath recharge basins on Long Island, New York (United States)

    Ku, H.F.; Simmons, D.L.


    Urban stormwater runoff was monitored during 1980-82 to investigate the source, type, quantity, and fate of contaminants routed to the more than 3,000 recharge basins on Long Island and to determine whether this runoff might be a significant source of contamination to the groundwater reservoir. Forty-six storms were monitored at five recharge basins in representative land use areas (strip commercial, shopping-mall parking lot, major highway, low-density residential, and medium-density residential). Runoff:precipitation ratios indicate that all storm runoff is derived from precipitation on impervious surfaces in the drainage area, except during storms of high intensity or long duration, when additional runoff can be derived from precipitation on permeable surfaces. Lead was present in highway runoff in concentrations up to 3300 micrograms/L, and chloride was found in parking lot runoff concentrations up to 1,100 mg/L during winter, when salt is used for deicing. In the five composite stormwater samples and nine groundwater grab samples that were analyzed for 113 EPA-designated ' priority pollutants, ' four constituents were detected in concentrations exceeding New York State guidelines of 50 micrograms/L for an individual organic compound in drinking water: p-chloro-m-cresol (79 micrograms/L); 2 ,4-dimethylphenol (96 micrograms/L); 4-nitrophenol (58 micrograms/L); and methylene chloride (230 micrograms/L in either groundwater or stormwater at the highway basin). One stormwater sample and two groundwater samples exceeded New York State guidelines for total organic compounds in drinking water (100 micrograms/L). The presence of these constituents is attributed to contamination from point sources rather than to the quality of runoff from urban areas. The median number of indicator bacteria in stormwater ranged from 0.1 to 10 billion MPN/100 ml. Fecal coliforms and fecal streptococci increased by 1 to 2 orders of magnitude during the warm season. The use of recharge

  19. Characterizing Field Biodegradation of N-nitrosodimethylamine (NDMA) in Groundwater with Active Reclaimed Water Recharge (United States)

    McCraven, S.; Zhou, Q.; Garcia, J.; Gasca, M.; Johnson, T.


    N-Nitrosodimethylamine (NDMA) is an emerging contaminant in groundwater, because of its aqueous miscibility, exceptional animal toxicity, and human carcinogenicity. NDMA detections in groundwater have been tracked to either decomposition of unsymmetrical dimethylhydrazine (UDMH) used in rocket fuel facilities or chlorine disinfection in wastewater reclamation plants. Laboratory experiments on both unsaturated and saturated soil samples have demonstrated that NDMA can be biodegraded by microbial activity, under both aerobic and anaerobic conditions. However, very limited direct evidence for its biodegradation has been found from the field in saturated groundwater. Our research aimed to evaluate photolysis and biodegradation of NDMA occurring along the full travel path - from wastewater reclamation plant effluent, through rivers and spreading grounds, to groundwater. For this evaluation, we established an extensive monitoring network to characterize NDMA concentrations at effluent discharge points, surface water stations, and groundwater monitoring and production wells, during the operation of the Montebello Forebay Groundwater Recharge facilities in Los Angeles County, California. Field monitoring for NDMA has been conducted for more than six years, including 32 months of relatively lower NDMA concentrations in effluent, 43 months of elevated NDMA effluent concentrations, and 7 months with significantly reduced NDMA effluent concentrations. The NDMA effluent concentration increase and significant concentration decrease were caused by changes in treatment processes. The NDMA sampling data imply that significant biodegradation occurred in groundwater, accounting for a 90% mass reduction of NDMA over the six-year monitoring period. In addition, the occurrence of a discrete well monitored effluent release during the study period allowed critical analysis of the fate of NDMA in a well- characterized, localized groundwater flow subsystem. The data indicate that 80% of the

  20. Experimental and numerical investigations of soil water balance at the hinterland of the Badain Jaran Desert for groundwater recharge estimation (United States)

    Hou, Lizhu; Wang, Xu-Sheng; Hu, Bill X.; Shang, Jie; Wan, Li


    Quantification of groundwater recharge from precipitation in the huge sand dunes is an issue in accounting for regional water balance in the Badain Jaran Desert (BJD) where about 100 lakes exist between dunes. In this study, field observations were conducted on a sand dune near a large saline lake in the BJD to investigate soil water movement through a thick vadose zone for groundwater estimation. The hydraulic properties of the soils at the site were determined using in situ experiments and laboratory measurements. A HYDRUS-1D model was built up for simulating the coupling processes of vertical water-vapor movement and heat transport in the desert soil. The model was well calibrated and validated using the site measurements of the soil water and temperature at various depths. Then, the model was applied to simulate the vertical flow across a 3-m-depth soil during a 53-year period under variable climate conditions. The simulated flow rate at the depth is an approximate estimation of groundwater recharge from the precipitation in the desert. It was found that the annual groundwater recharge would be 11-30 mm during 1983-2012, while the annual precipitation varied from 68 to 172 mm in the same period. The recharge rates are significantly higher than those estimated from the previous studies using chemical information. The modeling results highlight the role of the local precipitation as an essential source of groundwater in the BJD.

  1. Groundwater recharge: Accurately representing evapotranspiration

    CSIR Research Space (South Africa)

    Bugan, Richard DH


    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...

  2. Arsenic mobilization and attenuation by mineral-water interactions: implications for managed aquifer recharge. (United States)

    Neil, Chelsea W; Yang, Y Jeffrey; Jun, Young-Shin


    Managed aquifer recharge (MAR) has potential for addressing deficits in water supplies worldwide. It is also widely used for preventing saltwater intrusion, maintaining the groundwater table, and augmenting ecological stream flows, among many other beneficial environmental applications. However, field MAR sites have experienced arsenic mobilization from aquifer formation minerals due to induced changes in groundwater chemistry. To address this environmental concern, it is crucial to understand the potential sources and sinks impacting arsenic mobilization. This paper outlines important mineral-water interactions that can occur at MAR sites. Detailed information on minerals of concern, physiochemical processes for arsenic mobilization or attenuation, and the potential impact of microbial activity and hydrology on these processes is provided. Based on these mineral-water interactions, guidelines for predicting arsenic mobility are presented, and recommendations are made concerning MAR site monitoring. The review emphasizes important aspects in correlating interfacial reactions to reactive transport modeling and elucidating future challenges, a first step toward developing safer and more sustainable MAR operations.

  3. Sustainable Hydro Assessment and Groundwater Recharge Projects (SHARP) in Germany - Water Balance Models (United States)

    Niemand, C.; Kuhn, K.; Schwarze, R.


    SHARP is a European INTERREG IVc Program. It focuses on the exchange of innovative technologies to protect groundwater resources for future generations by considering the climate change and the different geological and geographical conditions. Regions involved are Austria, United Kingdom, Poland, Italy, Macedonia, Malta, Greece and Germany. They will exchange practical know-how and also determine know-how demands concerning SHARP’s key contents: general groundwater management tools, artificial groundwater recharge technologies, groundwater monitoring systems, strategic use of groundwater resources for drinking water, irrigation and industry, techniques to save water quality and quantity, drinking water safety plans, risk management tools and water balance models. SHARP Outputs & results will influence the regional policy in the frame of sustainable groundwater management to save and improve the quality and quantity of groundwater reservoirs for future generations. The main focus of the Saxon State Office for Environment, Agriculture and Landscape in this project is the enhancement and purposive use of water balance models. Already since 1992 scientists compare different existing water balance models on different scales and coupled with groundwater models. For example in the KLIWEP (Assessment of Impacts of Climate Change Projections on Water and Matter Balance for the Catchment of River Parthe in Saxony) project the coupled model WaSiM-ETH - PCGEOFIM® has been used to study the impact of climate change on water balance and water supplies. The project KliWES (Assessment of the Impacts of Climate Change Projections on Water and Matter Balance for Catchment Areas in Saxony) still running, comprises studies of fundamental effects of climate change on catchments in Saxony. Project objective is to assess Saxon catchments according to the vulnerability of their water resources towards climate change projections in order to derive region-specific recommendations for

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

    NARCIS (Netherlands)

    Nyagwambo, N.L.


    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

  5. Atlantis Water Supply Scheme (AWSS) artificial recharge scientific and operational support

    CSIR Research Space (South Africa)

    Jovanovic, Nebojsa


    Full Text Available , Stellenbosch, South Africa 2City of Cape Town, South Africa CSIR, PO Box 395, Pretoria, South Africa, 0001 Email: ? WHAT IS MANAGED AQUIFER RECHARGE? Managed Aquifer Recharge (MAR) is defined by the transfer of surface...

  6. Hydro-geochemical characterization of Treated Domestic Waste Water for possible use in homestead irrigation and managed aquifer recharge in the coastal city of Khulna, Bangladesh (United States)

    Hamid, T.; Ahmed, K. M.


    Bangladesh is among the most densely populated countries in the world. Rapid and unplanned urbanization in Bangladesh has resulted in heterogeneous land use pattern and larger demands for municipal water. To meet the ever-increasing demand of water for such population, the usage of treated domestic waste water (DWW) has become a viable option that can serve specific purposes, i.e. homestead irrigation, managed aquifer recharge (MAR) in major cities like Khulna, the largest city in the southwest coastal region. It is an attractive solution to minimize the deficit between the demand and supply of water in the study area where, in specific parts, city-dwellers suffer year round shortage of potable water due to high salinity in shallow depths. However, certain degree of treatment is mandatory for DWW in order to ensure the compliance of the output water with a set of standards and regulations for the DWW reuse. At present, the DWW is being treated through Constructed Wetlands but the treated water is not used and discharged into the sewer system. Wastewater that has been treated through a constructed wetland is a resource that can be used for productive uses in homestead garden irrigation, artificial aquifer recharge, and other non-potable uses. The study addresses the effectiveness of constructed wetlands in improving the quality of wastewater through on the hydro-geochemical characterization of both raw and treated DWW as well as baseline water quality analysis of surface and ground water in and around the treatment plant with consideration of seasonal variations. The study aims at sustainable development through conservation of water, satisfaction of demands, reliability of water supply, contribution to urban food supply, sustenance of livelihood and replenishment of the depleting aquifer by assessing the suitability of the treated DWW for various non-potable uses and also to provide guidelines for possible uses of treated DWW without adverse impact on environment

  7. Spatial Distribution of Ground-Water Recharge Estimated with a Water-Budget Method for the Jordan Creek Watershed, Lehigh County, Pennsylvania (United States)

    Risser, Dennis W.


    This report presents the results of a study by the U.S. Geological Survey, in cooperation with the Pennsylvania Geological Survey, to illustrate a water-budget method for mapping the spatial distribution of ground-water recharge for a 76-square-mile part of the Jordan Creek watershed, northwest of Allentown, in Lehigh County, Pennsylvania. Recharge was estimated by using the Hydrological Evaluation of Landfill Performance (HELP) water-budget model for 577 landscape units in Jordan Creek watershed, delineated on the basis of their soils, land use/land cover, and mean annual precipitation during 1951-2000. The water-budget model routes precipitation falling on each landscape unit to components of evapotranspiration, surface runoff, storage, and vertical percolation (recharge) for a five-layer soil column on a daily basis. The spatial distribution of mean annual recharge during 1951-2000 for each landscape unit was mapped by the use of a geographic information system. Recharge simulated by the water-budget model in Jordan Creek watershed during 1951-2000 averaged 12.3 inches per year and ranged by landscape unit from 0.11 to 17.05 inches per year. Mean annual recharge during 1951-2000 simulated by the water-budget model was most sensitive to changes to input values for precipitation and runoff-curve number. Mean annual recharge values for the crop, forest, pasture, and low-density urban land-use/land-cover classes were similar (11.2 to 12.2 inches per year) but were substantially less for high-density urban (6.8 inches per year), herbaceous wetlands (2.5 inches per year), and forested wetlands (1.3 inches per year). Recharge rates simulated for the crop, forest, pasture, and low-density urban land-cover classes were similar because those land-use/land-cover classes are represented in the model with parameter values that either did not significantly affect simulated recharge or tended to have offsetting effects on recharge. For example, for landscapes with forest land

  8. Geochemical Effects of Induced Stream-Water and Artificial Recharge on the Equus Beds Aquifer, South-Central Kansas, 1995-2004 (United States)

    Schmidt, Heather C. Ross; Ziegler, Andrew C.; Parkhurst, David L.


    Artificial recharge of the Equus Beds aquifer is part of a strategy implemented by the city of Wichita, Kansas, to preserve future water supply and address declining water levels in the aquifer of as much as 30 feet caused by withdrawals for water supply and irrigation since the 1940s. Water-level declines represent a diminished water supply and also may accelerate migration of saltwater from the Burrton oil field to the northwest and the Arkansas River to the southwest into the freshwater of the Equus Beds aquifer. Artificial recharge, as a part of the Equus Beds Ground-Water Recharge Project, involves capturing flows larger than base flow from the Little Arkansas River and recharging the water to the Equus Beds aquifer by means of infiltration or injection. The geochemical effects on the Equus Beds aquifer of induced stream-water and artificial recharge at the Halstead and Sedgwick sites were determined through collection and analysis of hydrologic and water-quality data and the application of statistical, mixing, flow and solute-transport, and geochemical model simulations. Chloride and atrazine concentrations in the Little Arkansas River and arsenic concentrations in ground water at the Halstead recharge site frequently exceeded regulatory criteria. During 30 percent of the time from 1999 through 2004, continuous estimated chloride concentrations in the Little Arkansas River at Highway 50 near Halstead exceeded the Secondary Drinking-Water Regulation of 250 milligrams per liter established by the U.S. Environmental Protection Agency. Chloride concentrations in shallow monitoring wells located adjacent to the stream exceeded the drinking-water criterion five times from 1995 through 2004. Atrazine concentrations in water sampled from the Little Arkansas River had large variability and were at or near the drinking-water Maximum Contaminant Level of 3.0 micrograms per liter as an annual average established by the U.S. Environmental Protection Agency. Atrazine

  9. Precipitation, Ground-water Hydrology, and Recharge Along the Eastern Slopes of the Sandia Mountains, Bernalillo County, New Mexico (United States)

    McCoy, Kurt J.; Blanchard, Paul J.


    The spatial and temporal distribution of recharge to carbonate and clastic aquifers along the eastern slopes of the Sandia Mountains was investigated by using precipitation, water-level, dissolved chloride, and specific-conductance data. The U.S. Geological Survey (USGS), in cooperation with the Bernalillo County Public Works Division, conducted a study to assess ground-water conditions and provide technical data that could be used as a basis for management and future planning of eastern Bernalillo County water resources. The intent of the investigation was to improve the current understanding of subsurface mechanisms controlling recharge dynamics in a geologically complex aquifer system. In the Sandia Mountains, precipitation events are generally limited to snowfalls in winter months and monsoon rainfall in late summer. Monthly meteorological data from weather stations in the study area indicate that monsoon rainfall during July and August constitutes close to one-third of annual precipitation totals. Following precipitation and snowmelt events, daily ground-water level data show low-amplitude, long-duration peaks in hydrographs of wells north and west of the Tijeras Fault. Hydrographs of monthly and biannual water-level data from across the study area show seasonal variation and water-level fluctuations in excess of 30 ft during a period of below-average precipitation. Water level observations in 67 percent of wells showing drought-induced water-level declines rebounded to at or near predrought conditions within 6 months of return to normal climate conditions. Cross-correlation of annual hydrologic data shows aquifer response to periods of monsoon recharge to persist from 1 to 6 months following events. The lag time between precipitation input and response of water levels or solute concentrations was largest near the Tijeras and Gutierrez Faults. These results indicate regional faults hydrologically isolate the Tijeras Graben from groundwater recharge originating

  10. Hydrologic and geochemical dynamics of vadose zone recharge in a mantled karst aquifer: Results of monitoring drip waters in Mystery Cave, Minnesota (United States)

    Doctor, Daniel H.; Alexander, E. Calvin; Jameson, Roy A.; Alexander, Scott C.


    Caves provide direct access to flows through the vadose zone that recharge karst aquifers. Although many recent studies have documented the highly dynamic processes associated with vadose zone flows in karst settings, few have been conducted in mantled karst settings, such as that of southeastern Minnesota. Here we present some results of a long-term program of cave drip monitoring conducted within Mystery Cave, Minnesota. In this study, two perennial ceiling drip sites were monitored between 1997 and 2001. The sites were located about 90 m (300 ft) apart along the same cave passage approximately 18 m (60 ft) below the surface; 7 to 9 m (20 to 30 ft) of loess and 12 m (40 ft) of flat-lying carbonate bedrock strata overlie the cave. Records of drip rate, electrical conductivity, and water temperature were obtained at 15 minute intervals, and supplemented with periodic sampling for major ion chemistry and water stable isotopes. Patterns in flow and geochemistry emerged at each of the two drip sites that were repeated year after year. Although one site responded relatively quickly (within 2-7 hours) to surface recharge events while the other responded more slowly (within 2-5 days), thresholds of antecedent moisture needed to be overcome in order to produce a discharge response at both sites. The greatest amount of flow was observed at both sites during the spring snowmelt period. Rainfall events less than 10 mm (0.4 in) during the summer months generally did not produce a drip discharge response, yet rapid drip responses were observed following intense storm events after periods of prolonged rainfall. The chemical data from both sites indicate that reservoirs of vadose zone water with distinct chemical signatures mixed during recharge events, and drip chemistry returned to a baseline composition during low flow periods. A reservoir with elevated chloride and sulfate concentrations impacts the slow-response drip site with each recharge event, but does not similarly

  11. Hydrochemistry of the Mahomet Bedrock Valley Aquifer, East-Central Illinois: indicators of recharge and ground-water flow (United States)

    Panno, S.V.; Hackley, Keith C.; Cartwright, K.; Liu, Chao-Li


    A conceptual model of the ground-water flow and recharge to the Mahomet Bedrock Valley Aquifer (MVA), east-central Illinois, was developed using major ion chemistry and isotope geochemistry. The MVA is a 'basal' fill in the east-west trending buried bedrock valley composed of clean, permeable sand and gravel to thicknesses of up to 61 m. It is covered by a thick sequence of glacial till containing thinner bodies of interbedded sand and gravel. Ground water from the MVA was found to be characterized by clearly defined geochemical regions with three distinct ground-water types. A fourth ground-water type was found at the confluence of the MVA and the Mackinaw Bedrock Valley Aquifer (MAK) to the west. Ground water in the Onarga Valley, a northeastern tributary of the MVA, is of two types, a mixed cation-SO42- type and a mixed cation-HCO3- type. The ground water is enriched in Na+, Ca2+, Mg2+, and SO42- which appears to be the result of an upward hydraulic gradient and interaction of deeper ground water with oxidized pyritic coals and shale. We suggest that recharge to the Onarga Valley and overlying aquifers is 100% from bedrock (leakage) and lateral flow from the MVA to the south. The central MVA (south of the Onarga Valley) is composed of relatively dilute ground water of a mixed cation-HCO3- type, with low total dissolved solids, and very low concentrations of Cl- and SO42-. Stratigraphic relationships of overlying aquifers and ground-water chemistry of these and the MVA suggest recharge to this region of the MVA (predominantly in Champaign County) is relatively rapid and primarily from the surface. Midway along the westerly flow path of the MVA (western MVA), ground water is a mixed cation-HCO3- type with relatively high Cl-, where Cl- increases abruptly by one to ??? two orders of magnitude. Data suggest that the increase in Cl- is the result of leakage of saline ground water from bedrock into the MVA. Mass-balance calculations indicate that approximately 9.5% of

  12. Integrating soil water and tracer balances, numerical modelling and GIS tools to estimate regional groundwater recharge: Application to the Alcadozo Aquifer System (SE Spain). (United States)

    Hornero, Jorge; Manzano, Marisol; Ortega, Lucía; Custodio, Emilio


    Groundwater recharge is one of the key variables for aquifer management and also one of the most difficult to be evaluated with acceptable accuracy. This is especially relevant in semiarid areas, where the processes involved in recharge are widely variable. Uncertainty should be estimated to know how reliable recharge estimations are. Groundwater recharge has been calculated in the Alcadozo Aquifer System, under steady state conditions, at regional (aquifer) and sub-regional (spring catchment) scales applying different methods. The regional distribution of long-term average recharge values has been estimated with the chloride mass balance method using data from four rain stations and 40 groundwater samples covering almost the whole aquifer surface. A remarkable spatial variability has been found. Average annual recharge rates ranges from 20 to 243mmyear(-1) across the aquifer, with an estimated coefficient of variation between 0.16 and 0.38. The average recharge/precipitation ratio decreases from 34% in the NW to 6% in the SE, following the topographic slope. At spring-catchment scale, recharge has been estimated by modelling the soil water balance with the code Visual Balan 2.0. The results, calibrated with discharge data of the two main springs Liétor and Ayna, are 35.5 and 50mmyear(-1) respectively, with estimated coefficients of variation of 0.49 and 0.36. A sensitivity analysis showed that soil parameters influence the most the uncertainty of recharge estimations. Recharge values estimated with both methods and at two temporal and spatial scales are consistent, considering the regional variability obtained with the chloride method and the respective confidence intervals. Evaluating the uncertainties of each method eased to compare their relative results and to check their agreement, which provided confidence to the values obtained. Thus, the use of independent methods together with their uncertainties is strongly recommended to constrain the magnitude and to

  13. Evaluation of geohydrologic framework, recharge estimates and ground-water flow of the Joshua Tree area, San Bernardino County, California (United States)

    Nishikawa, Tracy; Izbicki, John A.; Hevesi, Joseph A.; Stamos, Christina L.; Martin, Peter


    Ground water historically has been the sole source of water supply for the community of Joshua Tree in the Joshua Tree ground-water subbasin of the Morongo ground-water basin in the southern Mojave Desert. The Joshua Basin Water District (JBWD) supplies water to the community from the underlying Joshua Tree ground-water subbasin. The JBWD is concerned with the long-term sustainability of the underlying aquifer. To help meet future demands, the JBWD plans to construct production wells in the adjacent Copper Mountain ground-water subbasin. As growth continues in the desert, there may be a need to import water to supplement the available ground-water resources. In order to manage the ground-water resources and to identify future mitigating measures, a thorough understanding of the ground-water system is needed. The purpose of this study was threefold: (1) improve the understanding of the geohydrologic framework of the Joshua Tree and Copper Mountain ground-water subbasins, (2) determine the distribution and quantity of recharge using field and numerical techniques, and (3) develop a ground-water flow model that can be used to help manage the water resources of the region. The geohydrologic framework was refined by collecting and interpreting water-level and water-quality data, geologic and electric logs, and gravity data. The water-bearing deposits in the Joshua Tree and Copper Mountain ground-water subbasins are Quarternary alluvial deposits and Tertiary sedimentary and volcanic deposits. The Quarternary alluvial deposits were divided into two aquifers (referred to as the 'upper' and the 'middle' alluvial aquifers), which are about 600 feet (ft) thick, and the Tertiary sedimentary and volcanic deposits were assigned to a single aquifer (referred to as the 'lower' aquifer), which is as thick as 1,500 ft. The ground-water quality of the Joshua Tree and Copper Mountain ground-water subbasins was defined by collecting 53 ground-water samples from 15 wells (10 in the

  14. Reclaimed water quality during simulated ozone-managed aquifer recharge hybrid

    KAUST Repository

    Yoon, Min


    A synergistic hybrid of two treatment processes, managed aquifer recharge (MAR) combined with ozonation, was proposed for wastewater reclamation and water reuse applications. Batch reactor and soil-column experiments were performed to evaluate reclaimed water quality using various chemical and bacterial analyses. The ozone process was optimized at low ozone dose (0.5 mg O3/mg DOC) based on the control of N-nitrosodimethylamine (<5 ng L-1) and bromate (<10 μg L-1), and applied prior to (i.e., O3-MAR) and after MAR (i.e., MAR-O3). This work demonstrates that effluent organic matter (EfOM) and trace organic contaminants (TOrCs) are effectively removed during the hybrid process of MAR combined ozonation, compared to MAR only. Based on fluorescence excitation-emission matrices analyses, both MAR and ozonation reduce soluble microbial (protein-like) products while only ozonation contributes in reducing humic and fulvic substances. Even at low ozone dose of 0.5 mg O3/mg DOC, the O3-MAR hybrid significantly reduced UV absorbance by ≥2 m-1, BDOC by ≥64 %, and total (Σ) TOrC concentrations by ≥70 % in the effluent water quality. However, no significant improvement (<10 %) in the removal of Σ16 TOrC concentrations was observed for the increased ozone dose at 1.0 mg O3/mg DOC during MAR combined ozonation processes. Overall, O3-MAR was effective by 10-30 % in treating effluent water than MAR based on DOC, UV254 nm EfOM, TOrC and bacterial analyses. In addition, MAR-O3 was better than O3-MAR for the reduction of fluorescence (close MQ), TOrCs (≥74 %) and total bacteria cell concentrations (>3 log reduction). Therefore, implementing MAR prior to ozonation appears to remove the bio-amenable compounds that react rapidly with ozone, thereby reducing oxidant demand and treatment efficiency. © 2014 Springer-Verlag Berlin Heidelberg.

  15. Impact of Land-use Patterns on Distributed Groundwater Recharge and Discharge——A Case Study of Western Jilin, China

    Institute of Scientific and Technical Information of China (English)

    Moiwo Juana PAUL


    The impact of land-use on distributed groundwater recharge and discharge in the western Jilin (WJ) was analyzed in this study. WJ is a transitional, semi-arid zone with a fragile, hydrological closed ecosystem in the Songhua River Basin (SRB). The research tool includes a seamlessly linked MODFLOW, WetSpass, the Seepage packages, and ArcGIS. The model calibration showed good agreement between simulated water table elevation and measured water table depths, while predicted groundwater discharge zones showed strong correlations with field occurrences of drainage systems and wetlands. Simulated averages for distributed recharge, water table elevation and groundwater drawdown were 377.42mm/yr, 194.43m, and 0.18m respectively. Forest vegetation showed the highest recharge, followed by agricultural farmlands, while open-water and other drainage systems constituted groundwater exit zones. When present land-use conditions were compared with the hypothetical natural pre-development scenario, an overall loss of groundwater recharge (24.09mm/yr) was observed, which for the project area is 18.05 × 108m3. Groundwater abstraction seemed to be the cause of water table drawdown, especially in the immediate vicinities of the supply wells. An important issue of the findings was the ability of the hypothetical forest vegetation to protect, and hence sustain aquifer reserves and dependent ecosystems. The profound data capture capability of ArcGIS makes it particularly useful in spatio-temporal hydroecological modeling.

  16. Artificial recharge of groundwater (United States)

    The Task Committee on Guidelines for Artificial Recharge of Groundwater, of the American Society of Civil Engineers' (ASCE) Irrigation and Drainage Division, sponsored an International Symposium on Artificial Recharge of Groundwater at the Inn-at-the-Park Hotel in Anaheim, Calif., August 23-27, 1988. Cosponsors were the U.S. Geological Survey, California Department of Water Resources, University of California Water Resources Center, Metropolitan Water District of Southern California, with cooperation from the U.S. Bureau of Reclamation, International Association of Hydrological Sciences, American Water Resources Association, U.S. Agency for International Development, World Bank, United Nations Department of Technical Cooperation for Development, and a number of local and state organizations.Because of the worldwide interest in artificial recharge and the need to develop efficient recharge facilities, the Anaheim symposium brought together an interdisciplinary group of engineers and scientists to provide a forum for many professional disciplines to exchange experiences and findings related to various types of artificial recharge; learn from both successful and unsuccessful case histories; promote technology transfer between the various disciplines; provide an education resource for communication with those who are not water scientists, such as planners, lawyers, regulators, and the public in general; and indicate directions by which cities or other entities can save funds by having reasonable technical guidelines for implementation of a recharge project.

  17. Vulnerability of shallow ground water and drinking-water wells to nitrate in the United States: Model of predicted nitrate concentration in shallow, recently recharged ground water -- Model output data set (gwava-s_out) (United States)

    U.S. Geological Survey, Department of the Interior — This data set represents predicted nitrate concentration in shallow, recently recharged ground water, in milligrams per liter, in the conterminous United States, and...

  18. Comparison of methods for estimating ground-water recharge and base flow at a small watershed underlain by fractured bedrock in the Eastern United States (United States)

    Risser, Dennis W.; Gburek, William J.; Folmar, Gordon J.


    This study by the U.S. Geological Survey (USGS), in cooperation with the Agricultural Research Service (ARS), U.S. Department of Agriculture, compared multiple methods for estimating ground-water recharge and base flow (as a proxy for recharge) at sites in east-central Pennsylvania underlain by fractured bedrock and representative of a humid-continental climate. This study was one of several within the USGS Ground-Water Resources Program designed to provide an improved understanding of methods for estimating recharge in the eastern United States. Recharge was estimated on a monthly and annual basis using four methods?(1) unsaturated-zone drainage collected in gravity lysimeters, (2) daily water balance, (3) water-table fluctuations in wells, and (4) equations of Rorabaugh. Base flow was estimated by streamflow-hydrograph separation using the computer programs PART and HYSEP. Estimates of recharge and base flow were compared for an 8-year period (1994-2001) coinciding with operation of the gravity lysimeters at an experimental recharge site (Masser Recharge Site) and a longer 34-year period (1968-2001), for which climate and streamflow data were available on a 2.8-square-mile watershed (WE-38 watershed). Estimates of mean-annual recharge at the Masser Recharge Site and WE-38 watershed for 1994-2001 ranged from 9.9 to 14.0 inches (24 to 33 percent of precipitation). Recharge, in inches, from the various methods was: unsaturated-zone drainage, 12.2; daily water balance, 12.3; Rorabaugh equations with PULSE, 10.2, or RORA, 14.0; and water-table fluctuations, 9.9. Mean-annual base flow from streamflow-hydrograph separation ranged from 9.0 to 11.6 inches (21-28 percent of precipitation). Base flow, in inches, from the various methods was: PART, 10.7; HYSEP Local Minimum, 9.0; HYSEP Sliding Interval, 11.5; and HYSEP Fixed Interval, 11.6. Estimating recharge from multiple methods is useful, but the inherent differences of the methods must be considered when comparing

  19. Contributing recharge areas to water-supply wells at Wright-Patterson Air Force Base, Ohio (United States)

    Sheets, R.A.


    Wright-Patterson Air Force Base, in southwestern Ohio, has operated three well fields--Area B, Skeel Road, and the East Well Fields--to supply potable water for consumption and use for base activities. To protect these well fields from contamination and to comply with the Ohio Wellhead Protection Plan, the Base is developing a wellhead-protection program for the well fields. A three-dimensional, steady-state ground-water-flow model was developed in 1993 to simulate heads in (1) the buried-valley aquifer system that is tapped by the two active well fields, and in (2) an upland bedrock aquifer that may supply water to the wells. An advective particle-tracking algorithm that requires estimated porosities and simulated heads was used to estimate ground-water-flow pathlines and traveltimes to the active well fields. Contributing recharge areas (CRA's)--areas on the water table that contribute water to a well or well field--were generated for 1-, 5-, and 10-year traveltimes. Results from the simulation and subsequent particle tracking indicate that the CRA's for the Skeel Road Well Fields are oval and extend north- ward, toward the Mad River, as pumping at the well field increases. The sizes of the 1-, 5-, and 10-year CRA's of Skeel Road Well Field, under maximum pumping conditions, are approximately 0.5, 1.5 and 3.2 square miles, respectively. The CRA's for the Area B Well Field extend to the north, up the Mad River Valley; as pumping increases at the well field, the CRA's extend up the Mad River Valley under Huffman Dam. The sizes of the 1-, 5-, and 10-year CRA's of Area B Well Field, under maximum pumping conditions, are approximately 0.1, 0.5, and 0.9 square miles, respectively. The CRA's for the East Well Field are affected by nearby streams under average pumping conditions. The sizes of the 1-, 5-, and 10-year CRA's of the East Well Field, under maximum pumping conditions, are approximately 0.2, 1.2, and 2.4 square miles, respectively. However, as pumping increases

  20. The effects of artificial recharge on groundwater levels and water quality in the west hydrogeologic unit of the Warren subbasin, San Bernardino County, California (United States)

    Stamos, Christina L.; Martin, Peter; Everett, Rhett; Izbicki, John A.


    Between the late 1940s and 1994, groundwater levels in the Warren subbasin, California, declined by as much as 300 feet because pumping exceeded sparse natural recharge. In response, the local water district, Hi-Desert Water District, implemented an artificial-recharge program in early 1995 using imported water from the California State Water Project. Subsequently, the water table rose by as much as 250 feet; however, a study done by the U.S. Geological Survey found that the rising water table entrained high-nitrate septic effluent, which caused nitrate (as nitrogen) concentrations in some wells to increase to more than the U.S. Environmental Protection Agency maximum contaminant level of 10 milligrams per liter.. A new artificial-recharge site (site 3) was constructed in 2006 and this study, which started in 2004, was done to address concerns about the possible migration of nitrates in the unsaturated zone. The objectives of this study were to: (1) characterize the hydraulic, chemical, and microbiological properties of the unsaturated zone; (2) monitor changes in water levels and water quality in response to the artificial-recharge program at site 3; (3) determine if nitrates from septic effluent infiltrated through the unsaturated zone to the water table; (4) determine the potential for nitrates within the unsaturated zone to mobilize and contaminate the groundwater as the water table rises in response to artificial recharge; and (5) determine the presence and amount of dissolved organic carbon because of its potential to react with disinfection byproducts during the treatment of water for public use. Two monitoring sites were installed and instrumented with heat-dissipation probes, advanced tensiometers, suction-cup lysimeters, and wells so that the arrival and effects of recharging water from the State Water Project through the 250 to 425 foot-thick unsaturated zone and groundwater system could be closely observed. Monitoring site YVUZ-1 was located between two

  1. Uncertainty in Climatology-Based Estimates of Shallow Ground Water Recharge (United States)

    The groundwater recharge (GR) estimates for flow and transport projections are often evaluated as a fixed percentage of average annual precipitation. The chemical transport in variably saturated heterogeneous porous media is not linearly related to the average velocity. The objective of this study w...

  2. Investigating the Energy-Water Usage Efficiency of the Reuse of Treated Municipal Wastewater for Artificial Groundwater Recharge. (United States)

    Fournier, Eric D; Keller, Arturo A; Geyer, Roland; Frew, James


    This project investigates the energy-water usage efficiency of large scale civil infrastructure projects involving the artificial recharge of subsurface groundwater aquifers via the reuse of treated municipal wastewater. A modeling framework is introduced which explores the various ways in which spatially heterogeneous variables such as topography, landuse, and subsurface infiltration capacity combine to determine the physical layout of proposed reuse system components and their associated process energy-water demands. This framework is applied to the planning and evaluation of the energy-water usage efficiency of hypothetical reuse systems in five case study regions within the State of California. Findings from these case study analyses suggest that, in certain geographic contexts, the water requirements attributable to the process energy consumption of a reuse system can exceed the volume of water that it is able to recover by as much as an order of magnitude.

  3. Evaluating storm-scale groundwater recharge dynamics with coupled weather radar data and unsaturated zone modeling (United States)

    Nasta, P.; Gates, J. B.; Lock, N.; Houston, A. L.


    Groundwater recharge rates through the unsaturated zone emerge from complex interactions within the soil-vegetation-atmosphere system that derive from nonlinear relationships amongst atmospheric boundary conditions, plant water use and soil hydraulic properties. While it is widely recognized that hydrologic models must capture soil water dynamics in order to provide reliable recharge estimates, information on episodic recharge generation remains uncommon, and links between storm-scale weather patterns and their influence on recharge is largely unexplored. In this study, the water balance of a heterogeneous one-dimensional soil domain (3 m deep) beneath a typical rainfed corn agro-ecosystem in eastern Nebraska was numerically simulated in HYDRUS-1D for 12 years (2001-2012) on hourly time steps in order to assess the relationships between weather events and episodic recharge generation. WSR-88D weather radar reflectivity data provided both rainfall forcing data (after estimating rain rates using the z/r ratio method) and a means of storm classification on a scale from convective to stratiform using storm boundary characteristics. Individual storm event importance to cumulative recharge generation was assessed through iterative scenario modeling (773 total simulations). Annual cumulative recharge had a mean value of 9.19 cm/yr (about 12 % of cumulative rainfall) with coefficient of variation of 73%. Simulated recharge generation events occurred only in late winter and spring, with a peak in May (about 35% of total annual recharge). Recharge generation is observed primarily in late spring and early summer because of the combination of high residual soil moisture following a winter replenishment period, heavy convective storms, and low to moderate potential evapotranspiration rates. During the growing season, high rates of root water uptake cause rapid soil water depletion, and the concurrent high potential evapotranspiration and low soil moisture prevented recharge

  4. Identifying hydrological pathways in the north basin of Lake Kivu using stable isotope ratios of meteoric recharge and surface water (United States)

    Balagizi, Charles M.; Kasereka, Marcellin M.; Terzerand, Stefan; Cuoco, Emilio; Liotta, Marcello


    A rain-gauge network of 12 stations was installed at different altitudes at Nyiragongo volcano (DR Congo) and surroundings and sampled on monthly basis between December 2013 and June 2015 to evaluate the isotopic signature of the meteoric recharge. Additional samples were collected on monthly basis from 5 rivers, 7 springs, 3 profiles in Kabuno bay and 2 others in the Main Basin of Lake Kivu to determine their water isotope compositions (δ18O and δ2H). The precipitation, surface and groundwater δ18O and δ2H values were thereafter used to estimate the groundwater recharge area, surface and groundwater inflow level to Lake Kivu, and for modeling water circulation in the north basin of Lake Kivu. The monthly precipitation isotope composition varied in a large range, whereas mean precipitation-weighed values ranged between -12.39‰ and 6.52‰ for δ2H, and from -4.02‰ to -0.91‰ for δ18O. Monthly values allowed to define a Local Meteoric Water Line of equation δ2H=7.96δ18O + 16.96. Our dataset, the first time series in the Virunga, implies that the δ18O and δ2H of precipitation are predominantly determined by the recycled moisture source area, while their clearly defined seasonality is driven by wind direction and precipitation amount changes. The δ18O, δ2H and deuterium-excess values revealed a convergence zone around Nyiragongo where the N-NE and S-SW trade winds come together. Moisture from the Nile River basin brought by the N-NE originating winds yielded depleted precipitation at local highlands, while that from the Congo River basin brought by the S-SW wind yielded enriched precipitation at lowlands. Rivers and springs monthly are included in the range of monthly precipitation values, and are thus indicative of lack of significant evaporation during aquifer recharge. The mean rivers and springs δ2H and δ18O, and the mean precipitation-weighed values revealed the presence of shallow groundwater recharged between 2100 and 2700m a.s.l., and deep

  5. Applicability of Artificial Recharge of Groundwater in the Yongding River Alluvial Fan in Beijing through Numerical Simulation

    Institute of Scientific and Technical Information of China (English)

    Qichen Hao; Jingli Shao; Yali Cui; Zhenhua Xie


    A groundwater transient flow model was developed to evaluate the applicability and ef-fectiveness of artificial recharge scenarios in the middle-upper part of the Yongding River alluvial fan in Beijing. These scenarios were designed by taking into account different types of recharge facilities and their infiltration rate with the Middle Route Project for South-to-North Water Transfer (MRP) as the recharge water source. The simulation results suggest that: (1) the maximum amount of artificial recharge water, for scenario I, would be 127.42×106 m3 with surface infiltration facilities;and would be 243.48×106 m3 for scenario II with surface infiltration and recharge wells under the constraint of the upper limit of groundwater;(2) with preferred pattern of recharge facilities, groundwater levels in both optimized recharge scenarios would not exceed the upper limit within the given recharge period;and (3) implementation of the recharge scenarios would efficiently increase the aquifer replenishment and the groundwater budget will change from-54.11×106 to 70.89×104 and 183.36×104 m3, respectively. In addi-tion, under these two scenarios groundwater level would rise up to 30 and 34 m, respectively, without increasing the amount of evaporation. The simulation results indicate that the proposed recharge sce-narios are practically feasible, and artificial recharge can also contribute to an efficient recovery of groundwater storage in Beijing.

  6. A simple daily soil-water balance model for estimating the spatial and temporal distribution of groundwater recharge in temperate humid areas (United States)

    Dripps, W.R.; Bradbury, K.R.


    Quantifying the spatial and temporal distribution of natural groundwater recharge is usually a prerequisite for effective groundwater modeling and management. As flow models become increasingly utilized for management decisions, there is an increased need for simple, practical methods to delineate recharge zones and quantify recharge rates. Existing models for estimating recharge distributions are data intensive, require extensive parameterization, and take a significant investment of time in order to establish. The Wisconsin Geological and Natural History Survey (WGNHS) has developed a simple daily soil-water balance (SWB) model that uses readily available soil, land cover, topographic, and climatic data in conjunction with a geographic information system (GIS) to estimate the temporal and spatial distribution of groundwater recharge at the watershed scale for temperate humid areas. To demonstrate the methodology and the applicability and performance of the model, two case studies are presented: one for the forested Trout Lake watershed of north central Wisconsin, USA and the other for the urban-agricultural Pheasant Branch Creek watershed of south central Wisconsin, USA. Overall, the SWB model performs well and presents modelers and planners with a practical tool for providing recharge estimates for modeling and water resource planning purposes in humid areas. ?? Springer-Verlag 2007.

  7. Documentation of input datasets for the soil-water balance groundwater recharge model of the Upper Colorado River Basin (United States)

    Tillman, Fred D


    The Colorado River and its tributaries supply water to more than 35 million people in the United States and 3 million people in Mexico, irrigating more than 4.5 million acres of farmland, and generating about 12 billion kilowatt hours of hydroelectric power annually. The Upper Colorado River Basin, encompassing more than 110,000 square miles (mi2), contains the headwaters of the Colorado River (also known as the River) and is an important source of snowmelt runoff to the River. Groundwater discharge also is an important source of water in the River and its tributaries, with estimates ranging from 21 to 58 percent of streamflow in the upper basin. Planning for the sustainable management of the Colorado River in future climates requires an understanding of the Upper Colorado River Basin groundwater system. This report documents input datasets for a Soil-Water Balance groundwater recharge model that was developed for the Upper Colorado River Basin.

  8. Comparative review and synthesis of ground-water recharge estimates for the Great Bend Prairie aquifer of Kansas (United States)

    US Fish and Wildlife Service, Department of the Interior — In this report I briefly outline the importance of and difficulties involved in estimating aquifer recharge and compare reported recharge estimates for the Great...

  9. Rechargeable Biofilm-Controlling Tubing Materials for Use in Dental Unit Water Lines


    Luo, Jie; Porteous, Nuala; Sun, Yuyu


    A simple and practical surface grafting approach was developed to introduce rechargeable N-halamine-based antimicrobial functionality onto the inner surfaces of continuous small-bore polyurethane (PU) dental unit waterline (DUWL) tubing. In this approach, tetrahydrofuran (THF) solution of a free-radical initiator, dicumyl peroxide (DCP), flowed through the PU tubing (inner diameter of 1/16 inch, or 1.6 mm) to diffuse DCP into the tube’s inner walls, which was used as initiator in the subseque...

  10. Does localized recharge occur at a discharge area within the ground-water flow system of Yucca Mountain, Nevada?

    Energy Technology Data Exchange (ETDEWEB)

    Czarnecki, J.B. [Geological Survey, Denver, CO (United States); Kroitoru, L. [Roy F. Weston, Inc., Washington, DC (United States); Ronen, D. [Weizmann Inst. of Science, Rehovot (Israel)]|[Hydrological Service, Jerusalem (Israel); Magaritz, M. [Weizmann Inst. of Science, Rehovot (Israel)


    Studies done in 1984, at a central site on Franklin Lake playa (also known as Alkali Flat, a major discharge area of the ground-water flow system that includes Yucca Mountain, Nevada, the potential site of a high-level nuclear-waste repository) yield limited hydraulic-head and hydrochemical data from a 3-piezometer nest which indicated a slightly downward hydraulic gradient ({minus}0.02) and decreasing concentration of dissolved solids with increasing depth. Hydraulic-head measurements in June, 1989 made at the piezometer nest showed a substantially larger downward gradient ({minus}0.10) and a 0. 83{minus}meter higher water level in the shallowest piezometer (3.29 meters deep), indicating the possibility of localized recharge. during the period of September-November, 1989, a multilevel sampler was used to obtain detailed hydrochemical profiles of the uppermost 1. 5 m of the saturated zone.

  11. Present-day groundwater recharge estimation in parts of the Indian Sub-Continent (United States)

    Bhanja, S. N.; Mukherjee, A.; Wada, Y.; Scanlon, B. R.; Taylor, R. G.; Rodell, M.; Malakar, P.


    Large part of global population has been dependent on groundwater as a source of fresh water. The demand would further increase with increasing population and stress associated with climate change. We tried to provide regional-scale groundwater recharge estimates in a large part of Indian Sub-Continent. A combination of ground-based, satellite-based and numerical model simulated recharge estimates were presented in the densely populated region. Three different methods: an intense network of observational wells (n>13,000 wells), a satellite (TRMM) and global land-surface model (CLM) outputs, and a global-scale hydrological model (PCR GLOBWB) were employed to calculate recharge estimates. Groundwater recharge values exhibit large spatial variations over the entire region on the basis of aquifer hydrogeology, precipitation and groundwater withdrawal patterns. Groundwater recharge estimates from all three estimation techniques were found to be higher (>300 mm/year) in fertile planes of Indus-Ganges-Brahmaputra (IGB) river basins. A combination of favorable hydrogeologic conditions (porosity, permeability etc.), comparatively higher rates of precipitation, and return flow from rapidly withdrawn irrigation water might influence occurrence of high recharge rates. However, central and southern study area experiences lower recharge rates (recharge estimates show good matches in some of the areas. Recharge estimates indicate dynamic nature of groundwater recharge as a function of precipitation, land use pattern, and hydrogeologic parameters. On a first hand basis, the estimates will help policy makers to understand groundwater recharge process over the densely populated region and finally would facilitate to implement sustainable policy for securing water security.

  12. Managed Aquifer Recharge Using Treated Wastewater: An Option to Manage a Coastal Aquifer In Oman For Better Domestic Water Supply (United States)

    Al-Maktoumi, Ali; Zekri, Slim; ElRawy, Mustafa


    Arid countries, such as the Sultanate of Oman, are facing challenges of water shortages threatening economic development and social stability. Most of those countries are vulnerable to the potential adverse impacts of climate change, the most significant of which are increased average temperatures, less and more erratic precipitation, sea level rise, and desertification. The combined effect of existing adverse conditions and likely impacts of future climate change will make water management even more difficult than what it is today. Tremendous efforts have been devoted to augment the water resources. Managed Aquifer Recharge (MAR) is practiced widely to store water during periods of surpluses and withdraw during deficits from an aquifer. In Muscat, there will be a surplus of >100,000 m3/day of TWW during winter months in the coming few years. The aquifer along the northern coast of Oman (Al-Khawd Aquifer) is conducive for MAR. Data show that TWW volumes will increase from 7.6 Mm3 in 2003 to 70.9 Mm3 in 2035 in Muscat city only. This study assesses, using MODFLOW 2005 numerical code, the impact of MAR using TWW on better management of the Al-Khawd unconfined coastal aquifer for better urban water supply. Specifically, aiming to maximize withdrawals from the domestic wells with minimize adverse effect of seawater intrusion. The model operates under a number of constrains that minimize the loss to the sea and the injected TWW must not migrates upstream (due to developed mound) and reach the wellfields used for domestic supply. The hypothetical injection wells are located downstream the domestic wellfield zone. The results of different managerial scenarios show that MAR produces a hydraulic barrier that decelerates the seawater intrusion which allows higher abstraction of pristine water from the upstream part of the aquifer. MAR along with redistribution/relocation of public wells allows abstraction of 2 times the current abstraction rate (around 6 Mm3/year to 12 Mm3

  13. Accounting for intracell flow in models with emphasis on water table recharge and stream-aquifer interaction. 1. Problems and concepts (United States)

    Jorgensen, D.G.; Signor, D.C.; Imes, J.L.


    One method of modeling multiple sources and sinks is to determine the net recharge per cell. For example, for a model cell containing both a sink and recharge through the water table, the amount of recharge should be reduced by the ratio of the area of influence of the sink within the cell to the area of the cell. The reduction is the intercepted portion of the recharge. In a multilayer model this amount is further reduced by a proportion factor, which is a function of the depth of the flow lines from the water table boundary to the internal sink. A gaining section of a stream is a typical sink. The aquifer contribution to a gaining stream can be conceptualized as having two parts; the first part is the intercepted lateral flow from the water table and the second is the flow across the streambed due to differences in head between the water level in the stream and the aquifer below. The amount intercepted is a function of the geometry of the cell, but the amount due to difference in head across the stream bed is largely independent of cell geometry. -from Authors

  14. A subsurface runoff parameterization with water storage and recharge based on the Boussinesq-Storage Equation for a Land Surface Model

    Institute of Scientific and Technical Information of China (English)

    TIAN; Xiangjun; XIE; Zhenghui; ZHANG; Shenglei


    Subsurface runoff in a land surface model is usually parameterized as a single-valued function of total storage in a basin aquifer reservoir. This kind of parameterization is often single-valued function of storage-discharge under a steady or "quasi-steady" state, which cannot represent the influence of aquifer recharge on subsurface runoff generation. In this paper, a new subsurface runoff parameterization with water storage and recharge based on the Boussinesq-storage equation is developed. This model is validated by a subsurface flow separation algorithm for an example river basin, which shows that the new model can simulate the subsurface flow reasonably.

  15. Organic micropollutant removal from wastewater effluent-impacted drinking water sources during bank filtration and artificial recharge. (United States)

    Maeng, Sung Kyu; Ameda, Emmanuel; Sharma, Saroj K; Grützmacher, Gesche; Amy, Gary L


    Natural treatment systems such as bank filtration (BF) and artificial recharge (via an infiltration basin) are a robust barrier for many organic micropollutants (OMPs) and may represent a low-cost alternative compared to advanced drinking water treatment systems. This study analyzes a comprehensive database of OMPs at BF and artificial recharge (AR) sites located near Lake Tegel in Berlin (Germany). The focus of the study was on the derivation of correlations between the removal efficiencies of OMPs and key factors influencing the performance of BF and AR. At the BF site, shallow monitoring wells located close to the Lake Tegel source exhibited oxic conditions followed by prolonged anoxic conditions in deep monitoring wells and a production well. At the AR site, oxic conditions prevailed from the recharge pond along monitoring wells to the production well. Long residence times of up to 4.5 months at the BF site reduced the temperature variation during soil passage between summer and winter. The temperature variations were greater at the AR site as a consequence of shorter residence times. Deep monitoring wells and the production well located at the BF site were under the influence of ambient groundwater and old bank filtrate (up to several years of age). Thus, it is important to account for mixing with native groundwater and other sources (e.g., old bank filtrate) when estimating the performance of BF with respect to removal of OMPs. Principal component analysis (PCA) was used to investigate correlations between OMP removals and hydrogeochemical conditions with spatial and temporal parameters (e.g., well distance, residence time and depth) from both sites. Principal component-1 (PC1) embodied redox conditions (oxidation-reduction potential and dissolved oxygen), and principal component-2 (PC2) embodied degradation potential (e.g., total organic carbon and dissolved organic carbon) with the calcium carbonate dissolution potential (Ca(2+) and HCO(3)(-)) for the BF

  16. Organic micropollutant removal from wastewater effluent-impacted drinking water sources during bank filtration and artificial recharge

    KAUST Repository

    Maeng, Sungkyu


    Natural treatment systems such as bank filtration (BF) and artificial recharge (via an infiltration basin) are a robust barrier for many organic micropollutants (OMPs) and may represent a low-cost alternative compared to advanced drinking water treatment systems. This study analyzes a comprehensive database of OMPs at BF and artificial recharge (AR) sites located near Lake Tegel in Berlin (Germany). The focus of the study was on the derivation of correlations between the removal efficiencies of OMPs and key factors influencing the performance of BF and AR. At the BF site, shallow monitoring wells located close to the Lake Tegel source exhibited oxic conditions followed by prolonged anoxic conditions in deep monitoring wells and a production well. At the AR site, oxic conditions prevailed from the recharge pond along monitoring wells to the production well. Long residence times of up to 4.5 months at the BF site reduced the temperature variation during soil passage between summer and winter. The temperature variations were greater at the AR site as a consequence of shorter residence times. Deep monitoring wells and the production well located at the BF site were under the influence of ambient groundwater and old bank filtrate (up to several years of age). Thus, it is important to account for mixing with native groundwater and other sources (e.g., old bank filtrate) when estimating the performance of BF with respect to removal of OMPs. Principal component analysis (PCA) was used to investigate correlations between OMP removals and hydrogeochemical conditions with spatial and temporal parameters (e.g., well distance, residence time and depth) from both sites. Principal component-1 (PC1) embodied redox conditions (oxidation-reduction potential and dissolved oxygen), and principal component-2 (PC2) embodied degradation potential (e.g., total organic carbon and dissolved organic carbon) with the calcium carbonate dissolution potential (Ca2+ and HCO3 -) for the BF site

  17. A computer program for predicting recharge with a master recession curve (United States)

    Heppner, Christopher S.; Nimmo, John R.


    Water-table fluctuations occur in unconfined aquifers owing to ground-water recharge following precipitation and infiltration, and ground-water discharge to streams between storm events. Ground-water recharge can be estimated from well hydrograph data using the water-table fluctuation (WTF) principle, which states that recharge is equal to the product of the water-table rise and the specific yield of the subsurface porous medium. The water-table rise, however, must be expressed relative to the water level that would have occurred in the absence of recharge. This requires a means for estimating the recession pattern of the water-table at the site. For a given site there is often a characteristic relation between the water-table elevation and the water-table decline rate following a recharge event. A computer program was written which extracts the relation between decline rate and water-table elevation from well hydrograph data and uses it to construct a master recession curve (MRC). The MRC is a characteristic water-table recession hydrograph, representing the average behavior for a declining water-table at that site. The program then calculates recharge using the WTF method by comparing the measured well hydrograph with the hydrograph predicted by the MRC and multiplying the difference at each time step by the specific yield. This approach can be used to estimate recharge in a continuous fashion from long-term well records. Presented here is a description of the code including the WTF theory and instructions for running it to estimate recharge with continuous well hydrograph data.

  18. Contamination risk and drinking water protection for a large-scale managed aquifer recharge site in a semi-arid karst region, Jordan (United States)

    Xanke, Julian; Liesch, Tanja; Goeppert, Nadine; Klinger, Jochen; Gassen, Niklas; Goldscheider, Nico


    Karst aquifers in semi-arid regions are particularly threatened by surface contamination, especially during winter seasons when extremely variable rainfall of high intensities prevails. An additional challenge is posed when managed recharge of storm water is applied, since karst aquifers display a high spatial variability of hydraulic properties. In these cases, adapted protection concepts are required to address the interaction of surface water and groundwater. In this study a combined protection approach for the surface catchment of the managed aquifer recharge site at the Wala reservoir in Jordan and the downstream Hidan wellfield, which are both subject to frequent bacteriological contamination, is developed. The variability of groundwater quality was evaluated by correlating contamination events to rainfall, and to recharge from the reservoir. Both trigger increased wadi flow downstream of the reservoir by surface runoff generation and groundwater seepage, respectively. A tracer test verified the major pathway of the surface flow into the underground by infiltrating from pools along Wadi Wala. An intrinsic karst vulnerability and risk map was adapted to the regional characteristics and developed to account for the catchment separation by the Wala Dam and the interaction of surface water and groundwater. Implementation of the proposed protection zones for the wellfield and the reservoir is highly recommended, since the results suggest an extreme contamination risk resulting from livestock farming, arable agriculture and human occupation along the wadi. The applied methods can be transferred to other managed aquifer recharge sites in similar karstic environments of semi-arid regions.

  19. Contamination risk and drinking water protection for a large-scale managed aquifer recharge site in a semi-arid karst region, Jordan (United States)

    Xanke, Julian; Liesch, Tanja; Goeppert, Nadine; Klinger, Jochen; Gassen, Niklas; Goldscheider, Nico


    Karst aquifers in semi-arid regions are particularly threatened by surface contamination, especially during winter seasons when extremely variable rainfall of high intensities prevails. An additional challenge is posed when managed recharge of storm water is applied, since karst aquifers display a high spatial variability of hydraulic properties. In these cases, adapted protection concepts are required to address the interaction of surface water and groundwater. In this study a combined protection approach for the surface catchment of the managed aquifer recharge site at the Wala reservoir in Jordan and the downstream Hidan wellfield, which are both subject to frequent bacteriological contamination, is developed. The variability of groundwater quality was evaluated by correlating contamination events to rainfall, and to recharge from the reservoir. Both trigger increased wadi flow downstream of the reservoir by surface runoff generation and groundwater seepage, respectively. A tracer test verified the major pathway of the surface flow into the underground by infiltrating from pools along Wadi Wala. An intrinsic karst vulnerability and risk map was adapted to the regional characteristics and developed to account for the catchment separation by the Wala Dam and the interaction of surface water and groundwater. Implementation of the proposed protection zones for the wellfield and the reservoir is highly recommended, since the results suggest an extreme contamination risk resulting from livestock farming, arable agriculture and human occupation along the wadi. The applied methods can be transferred to other managed aquifer recharge sites in similar karstic environments of semi-arid regions.

  20. Integrated frameworks for assessing and managing health risks in the context of managed aquifer recharge with river water. (United States)

    Assmuth, Timo; Simola, Antti; Pitkänen, Tarja; Lyytimäki, Jari; Huttula, Timo


    Integrated assessment and management of water resources for the supply of potable water is increasingly important in light of projected water scarcity in many parts of the world. This article develops frameworks for regional-level waterborne human health risk assessment of chemical and microbiological contamination to aid water management, incorporating economic aspects of health risks. Managed aquifer recharge with surface water from a river in Southern Finland is used as an illustrative case. With a starting point in watershed governance, stakeholder concerns, and value-at-risk concepts, we merge common methods for integrative health risk analysis of contaminants to describe risks and impacts dynamically and broadly. This involves structuring analyses along the risk chain: sources-releases-environmental transport and fate-exposures-health effects-socio-economic impacts-management responses. Risks attributed to contaminants are embedded in other risks, such as contaminants from other sources, and related to benefits from improved water quality. A set of models along this risk chain in the case is presented. Fundamental issues in the assessment are identified, including 1) framing of risks, scenarios, and choices; 2) interaction of models and empirical information; 3) time dimension; 4) distributions of risks and benefits; and 5) uncertainties about risks and controls. We find that all these combine objective and subjective aspects, and involve value judgments and policy choices. We conclude with proposals for overcoming conceptual and functional divides and lock-ins to improve modeling, assessment, and management of complex water supply schemes, especially by reflective solution-oriented interdisciplinary and multi-actor deliberation.

  1. Spatiotemporal variation of the surface water effect on the groundwater recharge in a low-precipitation region: Application of the multi-tracer approach to the Taihang Mountains, North China (United States)

    Sakakibara, Koichi; Tsujimura, Maki; Song, Xianfang; Zhang, Jie


    Groundwater recharge variations in time and space are crucial for effective water management, especially in low-precipitation regions. To determine comprehensive groundwater recharge processes in a catchment with large seasonal hydrological variations, intensive field surveys were conducted in the Wangkuai Reservoir watershed located in the Taihang Mountains, North China, during three different times of the year: beginning of the rainy season (June 2011), mid-rainy season (August 2012), and dry season (November 2012). Oxygen and hydrogen isotope and chemical analyses were conducted on the groundwater, spring water, stream water, and reservoir water of the Wangkuai Reservoir watershed. The results were processed using endmember mixing analysis to determine the amount of contribution of the groundwater recharging processes. Similar isotopic and chemical signatures between the surface water and groundwater in the target area indicate that the surface water in the mountain-plain transitional area and the Wangkuai Reservoir are the principal groundwater recharge sources, which result from the highly permeable geological structure of the target area and perennial large-scale surface water, respectively. Additionally, the widespread and significant effect of the diffuse groundwater recharge on the Wangkuai Reservoir was confirmed with the deuterium (d) excess indicator and the high contribution throughout the year, calculated using endmember mixing analysis. Conversely, the contribution of the stream water to the groundwater recharge in the mountain-plain transitional area clearly decreases from the beginning of the rainy season to the mid-rainy season, whereas that of the precipitation increases. This suggests that the main groundwater recharge source shifts from stream water to episodic/continuous heavy precipitation in the mid-rainy season. In other words, the surface water and precipitation commonly affect the groundwater recharge in the rainy season, whereas the

  2. Uneven moisture patterns in water repellent soils

    NARCIS (Netherlands)

    Dekker, L.W.; Ritsema, C.J.


    In the Netherlands, water-repellent soils are widespread and they often show irregular moisture patterns, which cause accelerated transport of water and solutes to the groundwater and surface water. Under grass cover, spatial variability in soil moisture content is high owing to fingered flow; in ar

  3. Characterization of Organic Carbon and Its Bioavailability in Recharge Waters and Aquifer Sediments: Implications for Groundwater Arsenic Contamination in Bangladesh (United States)

    Pracht, L. E.; Ardissono, R. J.; Polizzotto, M.; Badruzzaman, A. B. M.; Ali, M. A.; Paša-Tolić, L.; Neumann, R. B.


    Arsenic contamination of groundwater in Bangladesh affects millions of people, as groundwater is the primary source of both drinking and irrigation water in the country. The arsenic is of geologic origin, naturally-occurring in the aquifer sediment. However, the source of organic carbon that fuels the microbial reactions responsible for mobilizing arsenic off the sediment and into the groundwater has been debated for over a decade. The outstanding question is whether this organic carbon is sedimentary carbon that was co-deposited when the aquifers were formed, or surface-derived organic carbon transported into the subsurface along with recharge water. The answer to this question has implications for managing the contamination problem. Here we present results of recent laboratory incubations of aquifer sediment with recharge waters collected from our field site in Bangladesh. The incubations revealed a hitherto undocumented pool of biodegradable sedimentary organic carbon. Despite the carbon being old (thousands of years), it was rapidly utilized by the native microbial population. The results imply that within the aquifer this pool of sedimentary organic carbon is largely unavailable to the microbial community, but that chemical and/or physical perturbations to the subsurface, induced, for example, by large-scale groundwater pumping or microbial activity, could mobilize this bioavailable organic carbon off the sediment. Currently, we are using Fourier Transform Ion Cyclotron Resonance Mass Spectrometry and spectroscopic techniques to understand the initial character of the mobilized organic carbon in our incubation experiments, and to track how its composition changes over time as it is degraded by microbes. These efforts will help clarify the in situ processes that could destabilize the sedimentary organic carbon and identify the components that make the carbon biologically available. Collectively, our data suggest a possible role for both surface-derived and

  4. Implications of projected climate change for groundwater recharge in the western United States (United States)

    Meixner, Thomas; Manning, Andrew H.; Stonestrom, David A.; Allen, Diana M.; Ajami, Hoori; Blasch, Kyle W.; Brookfield, Andrea E.; Castro, Christopher L.; Clark, Jordan F.; Gochis, David J.; Flint, Alan L.; Neff, Kirstin L.; Niraula, Rewati; Rodell, Matthew; Scanlon, Bridget R.; Singha, Kamini; Walvoord, Michelle A.


    Existing studies on the impacts of climate change on groundwater recharge are either global or basin/location-specific. The global studies lack the specificity to inform decision making, while the local studies do little to clarify potential changes over large regions (major river basins, states, or groups of states), a scale often important in the development of water policy. An analysis of the potential impact of climate change on groundwater recharge across the western United States (west of 100° longitude) is presented synthesizing existing studies and applying current knowledge of recharge processes and amounts. Eight representative aquifers located across the region were evaluated. For each aquifer published recharge budget components were converted into four standard recharge mechanisms: diffuse, focused, irrigation, and mountain-systems recharge. Future changes in individual recharge mechanisms and total recharge were then estimated for each aquifer. Model-based studies of projected climate-change effects on recharge were available and utilized for half of the aquifers. For the remainder, forecasted changes in temperature and precipitation were logically propagated through each recharge mechanism producing qualitative estimates of direction of changes in recharge only (not magnitude). Several key patterns emerge from the analysis. First, the available estimates indicate average declines of 10-20% in total recharge across the southern aquifers, but with a wide range of uncertainty that includes no change. Second, the northern set of aquifers will likely incur little change to slight increases in total recharge. Third, mountain system recharge is expected to decline across much of the region due to decreased snowpack, with that impact lessening with higher elevation and latitude. Factors contributing the greatest uncertainty in the estimates include: (1) limited studies quantitatively coupling climate projections to recharge estimation methods using detailed

  5. Hydrology of the Poverty Bay flats aquifers, New Zealand: recharge mechanisms, evolution of the isotopic composition of dissolved inorganic carbon, and ground-water ages (United States)

    Taylor, C. B.


    With the exception of water-bearing remnants of earlier fluvial gravels overlying basement, the sediments of the Poverty Bay flats have accumulated during the postglacial period of the past 14 000 years, and have been tilted and deformed by recent tectonism. A sequence of gravel aquifers, separated by poorly permeable silt layers, lies between surface and basement, which is at depths varying between 50 and 200 m. A shallow sand/silt aquifer is situated near the coast. This study applies evidence of chemical and isotopic properties of river and ground water to clarify the recharge mechanisms, chemical evolution and age of the ground water in the aquifers. Particular attention is paid to the evolution of dissolved inorganic carbon content, applying carbon-14 data measured by accelerator mass spectrometry. Most of the ground water is recharged from the Waipaoa River, which flows across the flats and discharges into Poverty Bay. The two deepest aquifers (Matokitoki and Makauri) are both tritium-free; the deeper Matokitoki Gravels yield water of age about 4300 years since recharge (possibly up to 1300 years greater), but the Makauri water is no older than 100-200 years, discharging slowly through overlying aquitards near the limit of closest approach to the present coast.

  6. The artificial recharge as a tool for the water resources management: case of the aquifer recharge system of Geneva (Switzerland); La recarga artificial de acuifero como ayuda a la gestion de los recursos hidricos; el ejemplo del sistema de Ginebra (Suiza)

    Energy Technology Data Exchange (ETDEWEB)

    Cobos, G. de los


    The drinking water supply for the Geneva area comes partly (80%) from the lake Geneva and partly (20%) from a large transboundary aquifer called Genevois aquifer. During the 70's, over pumping lowered the groundwater level by more than 7m. Artificial recharge has been carried out from the Arve river into the Genevois aquifer in order to maintain the groundwater level and enable water resources management. Located near the Arve river, this artificial recharge plant started its activity in 1980. For the last almost 30 years the artificial recharge system of Geneva has brought over 230 hm{sup 3} of treated water into the Genevois aquifer. The impacts of the recharge on the Genevois aquifer and on the aquifer management are described in this paper. (Author) 20 refs.

  7. Water Quality in the Equus Beds Aquifer and the Little Arkansas River Before Implementation of Large-Scale Artificial Recharge, South-Central Kansas, 1995-2005 (United States)

    Ziegler, Andrew C.; Hansen, Cristi V.; Finn, Daniel A.


    Artificial recharge of the Equus Beds aquifer using runoff from the Little Arkansas River in south-central Kansas was first proposed in 1956 and was one of many options considered by the city of Wichita to preserve its water supply. Declining aquifer water levels of as much as 50 feet exacerbated concerns about future water availability and enhanced migration of saltwater into the aquifer from past oil and gas activities near Burrton and from the Arkansas River. Because Wichita changed water-management strategies and decreased pumping from the Equus Beds aquifer in 1992, water storage in the aquifer recovered by about 50 percent. This recovery is the result of increased reliance on Cheney Reservoir for Wichita water supply, decreased aquifer pumping, and larger than normal precipitation. Accompanying the water-level recovery, the average water-level gradient in the aquifer decreased from about 12 feet per mile in 1992 to about 8 feet per mile in January 2006. An important component of artificial recharge is the water quality of the receiving aquifer and the water being recharged (source water). Water quality within the Little Arkansas River was defined using data from two real-time surface-water-quality sites and discrete samples. Water quality in the Equus Beds aquifer was defined using sample analyses collected at 38 index sites, each with a well completed in the shallow and deep parts of the Equus Beds aquifer. In addition, data were collected at diversion well sites, recharge sites, background wells, and prototype wells for the aquifer storage and recovery project. Samples were analyzed for major ions, nutrients, trace metals, radionuclides, organic compounds, and bacterial and viral indicators. Water-quality constituents of concern for artificial recharge are those constituents that frequently (more than 5 percent of samples) may exceed Federal [U.S. Environmental Protection Agency (USEPA)] and State drinking-water criteria in water samples from the receiving

  8. Contributing recharge areas, groundwater travel time, and groundwater water quality of the Missouri River alluvial aquifer near the City of Independence, Missouri, well field, 1997-2008 (United States)

    Kelly, Brian P.


    The City of Independence, Missouri, operates a well field in the Missouri River alluvial aquifer. Contributing recharge areas (CRA) were last determined for the well field in 1996. Since that time, eight supply wells have been installed in the area north of the Missouri River and well pumpage has changed for the older supply wells. The change in pumping has altered groundwater flow and substantially changed the character of the CRA and groundwater travel times to the supply wells. The U.S Geological Survey, in a cooperative study with the City of Independence, Missouri, simulated steady-state groundwater flow for 2007 well pumpage, average annual river stage, and average annual recharge. Particle-tracking analysis was used to determine the CRA for supply wells and monitoring wells, and the travel time from recharge areas to supply wells, recharge areas to monitoring wells, and monitoring wells to supply wells. The simulated CRA for the well field is elongated in the upstream direction and extends to both sides of the Missouri River. Groundwater flow paths and recharge areas estimated for monitoring wells indicate the origin of water to each monitoring well, the travel time of that water from the recharge area, the flow path from the vicinity of each monitoring well to a supply well, and the travel time from the monitoring well to the supply well. Monitoring wells 14a and 14b have the shortest groundwater travel time from their contributing recharge area of 0.30 years and monitoring well 29a has the longest maximum groundwater travel time from its contributing recharge area of 1,701 years. Monitoring well 22a has the shortest groundwater travel time of 0.5 day to supply well 44 and monitoring well 3b has the longest maximum travel time of 31.91 years to supply well 10. Water-quality samples from the Independence groundwater monitoring well network were collected from 1997 to 2008 by USGS personnel during ongoing annual sampling within the 10-year contributing

  9. Multiple-methods investigation of recharge at a humid-region fractured rock site, Pennsylvania, USA (United States)

    Heppner, C.S.; Nimmo, J.R.; Folmar, G.J.; Gburek, W.J.; Risser, D.W.


    Lysimeter-percolate and well-hydrograph analyses were combined to evaluate recharge for the Masser Recharge Site (central Pennsylvania, USA). In humid regions, aquifer recharge through an unconfined low-porosity fractured-rock aquifer can cause large magnitude water-table fluctuations over short time scales. The unsaturated hydraulic characteristics of the subsurface porous media control the magnitude and timing of these fluctuations. Data from multiple sets of lysimeters at the site show a highly seasonal pattern of percolate and exhibit variability due to both installation factors and hydraulic property heterogeneity. Individual event analysis of well hydrograph data reveals the primary influences on water-table response, namely rainfall depth, rainfall intensity, and initial water-table depth. Spatial and seasonal variability in well response is also evident. A new approach for calculating recharge from continuous water-table elevation records using a master recession curve (MRC) is demonstrated. The recharge estimated by the MRC approach when assuming a constant specific yield is seasonal to a lesser degree than the recharge estimate resulting from the lysimeter analysis. Partial reconciliation of the two recharge estimates is achieved by considering a conceptual model of flow processes in the highly-heterogeneous underlying fractured porous medium. ?? Springer-Verlag 2007.

  10. Probability of nitrate contamination of recently recharged ground waters in the conterminous United States (United States)

    U.S. Geological Survey, Department of the Interior — This data set is a national map of predicted probability of nitrate contamination of shallow ground waters based on a logistic regression (LR) model. The LR model...

  11. The future of Managed Aquifer Recharge in Italy: the European FPVII MARSOL Project and the European Innovation Partnership on Water Mar to Market

    Directory of Open Access Journals (Sweden)

    Rudy Rossetto


    Full Text Available Water scarcity, especially in the Mediterranean rim, poses the relevant issue of water saving in human activities and of finding new sources of water, also for agro-ecosystem maintenance. Managed Aquifer Recharge (MAR techniques constitute a promising solution to the above-mentioned issue. In this contribution, we discuss the state of MAR application in Italy also in relation to some projects co-funded by the European Union. Some ideas for the large scale application of these techniques for non-conventional water use are presented.

  12. Sources of water for the outflow channels on Mars: Implications of the Late Noachian "icy highlands" model for melting and groundwater recharge on the Tharsis rise (United States)

    Cassanelli, James P.; Head, James W.; Fastook, James L.


    From the Late Noachian period, through the Hesperian, and into the Amazonian periods on Mars, large outflow channels were formed. Many are interpreted to have originated through the catastrophic discharge of groundwater from martian aquifers, involving the release of up to millions of cubic-kilometers of water. Such a mechanism for outflow channel formation requires that martian aquifers were supplied with significant quantities of water some time prior to the discharge events. Typical groundwater recharge occurs due to the infiltration of surficial waters through a permeable substrate down into aquifers. However, some climate models predict an early martian climate dominated by generally "cold and icy" conditions. In this scenario, a globally continuous, impermeable cryosphere prevents infiltration of liquid water (that might be generated at the surface through anomalous heating conditions), leaving the martian aquifers without an apparent source of recharge to supply later outflow channel formation by groundwater discharge. More recent global climate modeling of an early, thicker CO2 martian atmosphere predicts that, when coupled with a full water cycle, the atmosphere of Mars will behave adiabatically causing temperatures to decrease with elevation. The high standing areas of Mars, such as the southern highlands and the Tharsis region, then act as cold traps. This leads to the preferential accumulation of snow and ice, resulting in the formation of regional ice sheets throughout the highlands that characterize the Late Noachian "icy highlands" early Mars climate model (LNIH). We make the initial assumption that the LNIH model is representative of the early Mars climate, and seek to test the model against the presence of the Hesperian and Amazonian outflow channels to determine if it can be consistent. In order to reconcile the LNIH early Mars climate model with the presence of the later outflow channels a groundwater recharge mechanism that can operate under the

  13. Groundwater recharge in Pleistocene sediments overlying basalt aquifers in the Palouse Basin, USA: modeling of distributed recharge potential and identification of water pathways

    NARCIS (Netherlands)

    Dijksma, R.; Brooks, E.S.; Boll, J.


    Groundwater levels in basalt aquifers around the world have been declining for many years. Understanding water pathways is needed for solutions like artificial drainage. Water supply in the Palouse Basin, Washington and Idaho, USA, primarily relies on basalt aquifers. This study presents a combinati

  14. Potential development and recharge of ground water in Mill Creek Valley, Butler and Hamilton Counties, Ohio, based on analog model analysis (United States)

    Fidler, Richard E.


    Mill Creek valley is part of the greater Cincinnati industrial area in southwestern Ohio. In 1964, nearly 30 percent of the water supply in the study area of about 27 square miles was obtained from wells in the glacial-outwash aquifer underlying the valley. Ground-water demand has increased steadily since the late 1800's, and excessive pumpage during the years of World War II caused water levels to decline to critical levels. Natural recharge to the aquifer, from precipitation, is about 8.5 mgd (million gallons per day). In 1964, the total water use was about 30 mgd, of which 8.1 mgd was obtained from wells in Mill Creek valley, and the remainder was imported from outside the basin. With rapid industrial expansion and population growth, demand for ground water is continuing to increase. By the year 2000 ground-water pumpage is expected to exceed 25 mgd. At a public hearing before the Ohio Water Commission in 1961, artificial recharge of the aquifer through injection wells was proposed as a possible solution to the Mill Creek valley water-supply problem. The present study attempts to determine the feasibility of injection-well recharge systems in the Mill Creek valley. Although basically simple, the hydrologic system in Mill Creek valley is complex in detail and is difficult to evaluate using conventional quantitative methods. Because of this complexity, an electric analog model was used to test specific development plans. Three hypothetical pumping plans were developed by projecting past pumpage data to the years 1980 and 2000. Various combinations of injection wells were tested on the model under different hypothetical conditions of pumpage. Based on analog model analysis, from three to eight inject-ion wells, with an approximate input of 2 mgd each, would reverse the trend in declining groundwater levels and provide adequate water to meet anticipated future demands.

  15. Considerations for Use of the Rora Program to Estimate Ground-Water Recharge From Streamflow Records (United States)


    inch per year (in/yr) 25.4 millimeter per year foot (ft) 0.3048 meter square mile (mi2) 2.590 square kilometer cubic foot per second (ft3...designates those parts of the record that represent ground-water discharge. In extremely flat areas, the time period of surface runoff may not several hydrologists (Gerhart, 1986; Hall and Risser , 1993; Meinzer and Stearns, 1929; Rasmussen and Andreasen, 1959). To isolate the rise caused

  16. On the treatment of evapotranspiration, soil moisture accounting, and aquifer recharge in monthly water balance models. (United States)

    Alley, W.M.


    Several two- to six-parameter regional water balance models are examined by using 50-year records of monthly streamflow at 10 sites in New Jersey. These models include variants of the Thornthwaite-Mather model, the Palmer model, and the more recent Thomas abcd model. Prediction errors are relatively similar among the models. However, simulated values of state variables such as soil moisture storage differ substantially among the models, and fitted parameter values for different models sometimes indicated an entirely different type of basin response to precipitation.-from Author

  17. Study on Recharge Ability of Ground Water Heat Pump System%地下水源热泵系统中回灌能力分析

    Institute of Scientific and Technical Information of China (English)



    近年,地下水源热泵技术在我国被广泛应用,并在节能、环保等方面取得了一定效益.但是,回灌问题仍是困扰我国地下水源热泵发展的瓶颈.以唐山市丰润区乡居假日住宅区A4区地下水源热泵系统的应用为例,从区域水文地质条件方面,对水源热泵系统中地下水回灌能力进行了分析,指出开展地下水源热泵项目时,掌握热源井所在区域水文地质条件的重要性.探讨了影响地下水回灌能力的关键因素,其中包括区域水文地质条件、热源井成井工艺、回灌井阻塞以及地下水回灌方式.%In recent years, ground water beat pump technology has been widely applied in China and has made certain benefits in energy saving and environmental protection. However, groundwater recharge is still the main difficulty. This paper studied on the recharge of ground water heat pump according to the local hydrogeologic conditions at A4 area in the Fengrun countryside holiday block in Tangshan City, pointed out that the local hydrogeological condition is very important, and discussed the key factors impacting the recharge ability of ground water heat pump, including local hydrogeologic conditions,heat source well completion technology, clogging problem of disposal well and groundwater recharge mode.

  18. Integrating urban recharge uncertainty into standard groundwater modeling practice: A case study on water main break predictions for the Barton Springs segment of the Edwards Aquifer, Austin, Texas (United States)

    Sinner, K.; Teasley, R. L.


    Groundwater models serve as integral tools for understanding flow processes and informing stakeholders and policy makers in management decisions. Historically, these models tended towards a deterministic nature, relying on historical data to predict and inform future decisions based on model outputs. This research works towards developing a stochastic method of modeling recharge inputs from pipe main break predictions in an existing groundwater model, which subsequently generates desired outputs incorporating future uncertainty rather than deterministic data. The case study for this research is the Barton Springs segment of the Edwards Aquifer near Austin, Texas. Researchers and water resource professionals have modeled the Edwards Aquifer for decades due to its high water quality, fragile ecosystem, and stakeholder interest. The original case study and model that this research is built upon was developed as a co-design problem with regional stakeholders and the model outcomes are generated specifically for communication with policy makers and managers. Recently, research in the Barton Springs segment demonstrated a significant contribution of urban, or anthropogenic, recharge to the aquifer, particularly during dry period, using deterministic data sets. Due to social and ecological importance of urban water loss to recharge, this study develops an evaluation method to help predicted pipe breaks and their related recharge contribution within the Barton Springs segment of the Edwards Aquifer. To benefit groundwater management decision processes, the performance measures captured in the model results, such as springflow, head levels, storage, and others, were determined by previous work in elicitation of problem framing to determine stakeholder interests and concerns. The results of the previous deterministic model and the stochastic model are compared to determine gains to stakeholder knowledge through the additional modeling

  19. Identification of key factors governing chemistry in groundwater near the water course recharged by reclaimed water at Miyun County, Northern China

    Institute of Scientific and Technical Information of China (English)

    Yilei Yu; Xianfang Song; Yinghua Zhang; Fandong Zheng; Ji Liang; Dongmei Han; Ying Ma


    Reclaimed water was successfully used to recover the dry Chaobai River in Northern China,but groundwater may be polluted.To ensure groundwater protection,it is therefore critical to identify the governing factors of groundwater chemistry.Samples of reclaimed water,river and groundwater were collected monthly at Chaobai River from January to September in 2010.Fifteen water parameters were analyzed.Two kinds of reclaimed water were different in type (Na-Ca-Mg-C1-HCO3 or Na-Ca-Cl-HCO3) and concentration of nitrogen.The ionic concentration and type in river were similar to reclaimed water.Some shallow wells near the river bed had the same type (Na-Ca-Mg-Cl-HCO3) and high concentration as reclaimed water,but others were consistent with the deep wells (Ca-Mg-HCO3).Using cluster analysis,the 9 months were divided into two periods (dry and wet seasons),and all samples were grouped into several spatial clusters,indicating different controlling mechanisms.Principal component analysis and conventional ionic plots showed that calcium,magnesium and bicarbonate were controlled by water-rock interaction in all deep and some shallow wells.This included the dissolution of calcite and carbonate weathering.Sodium,potassium,chloride and sulfate in river and some shallow wells recharged by river were governed by evaporation crystallization and mixing of reclaimed water.But groundwater chemistry was not controlled by precipitation.During the infiltration of reclaimed water,cation exchange took place between (sodium,potassium) and (calcium,magnesium).Nitrification and denitrification both happened in most shallow groundwater,but only denitrification in deep groundwater.

  20. Effect of ground-water recharge on configuration of the water table beneath sand dunes and on seepage in lakes in the sandhills of Nebraska, U.S.A. (United States)

    Winter, T.C.


    Analysis of water-level fluctuations in about 30 observation wells and 5 lakes in the Crescent Lake National Wildlife Refuge in the sandhills of Nebraska indicates water-table configuration beneath sand dunes in this area varies considerably, depending on the configuration of the topography of the dunes. If the topography of an interlake dunal area is hummocky, ground-water recharge is focused at topographic lows causing formation of water-table mounds. These mounds prevent ground-water movement from topographically high lakes to adjacent lower lakes. If a dune ridge is sharp, the opportunity for focused recharge does not exist, resulting in water-table troughs between lakes. Lakes aligned in descending altitudes, parallel to the principal direction of regional ground-water movement, generally have seepage from higher lakes toward lower lakes. ?? 1986.

  1. Evaluating prediction uncertainty of areas contributing recharge to well fields of multiple water suppliers in the Hunt-Annaquatucket-Pettaquamscutt River Basins, Rhode Island (United States)

    Friesz, Paul J.


    Three river basins in central Rhode Island-the Hunt River, the Annaquatucket River, and the Pettaquamscutt River-contain 15 production wells clustered in 4 pumping centers from which drinking water is withdrawn. These high-capacity production wells, operated by three water suppliers, are screened in coarse-grained deposits of glacial origin. The risk of contaminating water withdrawn by these well centers may be reduced if the areas contributing recharge to the well centers are delineated and these areas protected from land uses that may affect the water quality. The U.S. Geological Survey, in cooperation with the Rhode Island Department of Health, began an investigation in 2009 to improve the understanding of groundwater flow and delineate areas contributing recharge to the well centers as part of an effort to protect the source of water to these well centers. A groundwater-flow model was calibrated by inverse modeling using nonlinear regression to obtain the optimal set of parameter values, which provide a single, best representation of the area contributing recharge to a well center. Summary statistics from the calibrated model were used to evaluate the uncertainty associated with the predicted areas contributing recharge to the well centers. This uncertainty analysis was done so that the contributing areas to the well centers would not be underestimated, thereby leaving the well centers inadequately protected. The analysis led to contributing areas expressed as a probability distribution (probabilistic contributing areas) that differ from a single or deterministic contributing area. Groundwater flow was simulated in the surficial deposits and the underlying bedrock in the 47-square-mile study area. Observations (165 groundwater levels and 7 base flows) provided sufficient information to estimate parameters representing recharge and horizontal hydraulic conductivity of the glacial deposits and hydraulic conductance of streambeds. The calibrated value for recharge

  2. Flood water storage as a resource for agriculture and groundwater recharge: the empting of artificial leaking ponds (United States)

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


    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

  3. Silt and gas accumulation beneath an artificial recharge spreading basin, Southwestern Utah, U.S.A. (United States)

    Heilweil, V.M.; Solomon, D.K.; Ortiz, G.


    Sand Hollow Reservoir in southwestern Utah, USA, is operated for both surface-water storage and artificial recharge to the underlying Navajo Sandstone. The total volume of estimated artificial recharge between 2002 and 2007 is 85 million cubic meters (69,000 acre-feet). Since 2002, artificial recharge rates have generally been declining and are inversely correlated with the increasing surface area of the reservoir. Permeability testing of core samples retrieved from beneath the reservoir indicates that this decline may not be due to silt accumulation. Artificial recharge rates also show much seasonal variability. Calculations of apparent intrinsic permeability show that these variations can only partly be explained by variation in water viscosity associated with seasonal changes in water temperature. Sporadic seasonal trends in recharge rates and intrinsic permeability during 2002-2004 could be associated with the large fluctuations in reservoir elevation and wetted area. From 2005 through 2007, the reservoir was mostly full and there has been a more consistent seasonal pattern of minimum recharge rates during the summer and maximum rates during the autumn. Total dissolved-gas pressure measurements indicate the presence of biogenic gas bubbles in the shallow sediments beneath the shallower parts of Sand Hollow Reservoir when the water is warmer. Permeability reduction associated with this gas clogging may contribute to the decrease in artificial recharge rates during the spring and summer, with a subsequently increasing recharge rates in the autumn associated with a decline in volume of gas bubbles. Other possible causes for seasonal variation in artificial recharge rates require further investigation.

  4. Water-budgets and recharge-area simulations for the Spring Creek and Nittany Creek Basins and parts of the Spruce Creek Basin, Centre and Huntingdon Counties, Pennsylvania, Water Years 2000–06 (United States)

    Fulton, John W.; Risser, Dennis W.; Regan, Robert S.; Walker, John F.; Hunt, Randall J.; Niswonger, Richard G.; Hoffman, Scott A.; Markstrom, Steven


    This report describes the results of a study by the U.S. Geological Survey in cooperation with ClearWater Conservancy and the Pennsylvania Department of Environmental Protection to develop a hydrologic model to simulate a water budget and identify areas of greater than average recharge for the Spring Creek Basin in central Pennsylvania. The model was developed to help policy makers, natural resource managers, and the public better understand and manage the water resources in the region. The Groundwater and Surface-water FLOW model (GSFLOW), which is an integration of the Precipitation-Runoff Modeling System (PRMS) and the Modular Groundwater Flow Model (MODFLOW-NWT), was used to simulate surface water and groundwater in the Spring Creek Basin for water years 2000–06. Because the groundwater and surface-water divides for the Spring Creek Basin do not coincide, the study area includes the Nittany Creek Basin and headwaters of the Spruce Creek Basin. The hydrologic model was developed by the use of a stepwise process: (1) develop and calibrate a PRMS model and steady-state MODFLOW-NWT model; (2) re-calibrate the steady-state MODFLOW-NWT model using potential recharge estimates simulated from the PRMS model, and (3) integrate the PRMS and MODFLOW-NWT models into GSFLOW. The individually calibrated PRMS and MODFLOW-NWT models were used as a starting point for the calibration of the fully coupled GSFLOW model. The GSFLOW model calibration was done by comparing observations and corresponding simulated values of streamflow from 11 streamgages and groundwater levels from 16 wells. The cumulative water budget and individual water budgets for water years 2000–06 were simulated by using GSFLOW. The largest source and sink terms are represented by precipitation and evapotranspiration, respectively. For the period simulated, a net surplus in the water budget was computed where inflows exceeded outflows by about 1.7 billion cubic feet (0.47 inches per year over the basin area

  5. Precipitation isotopes link regional climate patterns to water supply in a tropical mountain forest, eastern Puerto Rico (United States)

    Scholl, Martha A.; Murphy, Sheila F.


    Like many mountainous areas in the tropics, watersheds in the Luquillo Mountains of eastern Puerto Rico have abundant rainfall and stream discharge and provide much of the water supply for the densely populated metropolitan areas nearby. Projected changes in regional temperature and atmospheric dynamics as a result of global warming suggest that water availability will be affected by changes in rainfall patterns. It is essential to understand the relative importance of different weather systems to water supply to determine how changes in rainfall patterns, interacting with geology and vegetation, will affect the water balance. To help determine the links between climate and water availability, stable isotope signatures of precipitation from different weather systems were established to identify those that are most important in maintaining streamflow and groundwater recharge. Precipitation stable isotope values in the Luquillo Mountains had a large range, from fog/cloud water with δ2H, δ18O values as high as +12 ‰, −0.73 ‰ to tropical storm rain with values as low as −127 ‰, −16.8 ‰. Temporal isotope values exhibit a reverse seasonality from those observed in higher latitude continental watersheds, with higher isotopic values in the winter and lower values in the summer. Despite the higher volume of convective and low-pressure system rainfall, stable isotope analyses indicated that under the current rainfall regime, frequent trade -wind orographic showers contribute much of the groundwater recharge and stream base flow. Analysis of rain events using 20 years of 15 -minute resolution data at a mountain station (643 m) showed an increasing trend in rainfall amount, in agreement with increased precipitable water in the atmosphere, but differing from climate model projections of drying in the region. The mean intensity of rain events also showed an increasing trend. The determination of recharge sources from stable isotope tracers indicates that water

  6. An approach to delineate groundwater recharge potential sites in Ambalantota, Sri Lanka using GIS techniques

    Directory of Open Access Journals (Sweden)

    I.P. Senanayake


    Full Text Available The demand for fresh water in Hambantota District, Sri Lanka is rapidly increasing with the enormous amount of ongoing development projects in the region. Nevertheless, the district experiences periodic water stress conditions due to seasonal precipitation patterns and scarcity of surface water resources. Therefore, management of available groundwater resources is critical, to fulfil potable water requirements in the area. However, exploitation of groundwater should be carried out together with artificial recharging in order to maintain the long term sustainability of water resources. In this study, a GIS approach was used to delineate potential artificial recharge sites in Ambalantota area within Hambantota. Influential thematic layers such as rainfall, lineament, slope, drainage, land use/land cover, lithology, geomorphology and soil characteristics were integrated by using a weighted linear combination method. Results of the study reveal high to moderate groundwater recharge potential in approximately 49% of Ambalantota area.

  7. An approach to delineate groundwater recharge potential sites in Ambalantota, Sri Lanka using GIS techniques

    Institute of Scientific and Technical Information of China (English)

    I.P. Senanayake; D.M.D.O.K. Dissanayake; B.B. Mayadunna; W.L. Weerasekera


    The demand for fresh water in Hambantota District, Sri Lanka is rapidly increasing with the enormous amount of ongoing development projects in the region. Nevertheless, the district experiences periodic water stress conditions due to seasonal precipitation patterns and scarcity of surface water resources. Therefore, management of available groundwater resources is critical, to fulfil potable water re-quirements in the area. However, exploitation of groundwater should be carried out together with artificial recharging in order to maintain the long term sustainability of water resources. In this study, a GIS approach was used to delineate potential artificial recharge sites in Ambalantota area within Ham-bantota. Influential thematic layers such as rainfall, lineament, slope, drainage, land use/land cover, li-thology, geomorphology and soil characteristics were integrated by using a weighted linear combination method. Results of the study reveal high to moderate groundwater recharge potential in approximately 49%of Ambalantota area.

  8. Morphology-Controllable Synthesis of Zn-Co-Mixed Sulfide Nanostructures on Carbon Fiber Paper Toward Efficient Rechargeable Zinc-Air Batteries and Water Electrolysis. (United States)

    Wu, Xiaoyu; Han, Xiaopeng; Ma, Xiaoya; Zhang, Wei; Deng, Yida; Zhong, Cheng; Hu, Wenbin


    It remains an ongoing challenge to develop cheap, highly active, and stable electrocatalysts to promote the sluggish electrocatalytic oxygen evolution, oxygen reduction, and hydrogen evolution reactions for rechargeable metal-air batteries and water-splitting systems. In this work, we report the morphology-controllable synthesis of zinc cobalt mixed sulfide (Zn-Co-S) nanoarchitectures, including nanosheets, nanoplates, and nanoneedles, grown on conductive carbon fiber paper (CFP) and the micronanostructure dependent electrochemical efficacy for catalyzing hydrogen and oxygen in zinc-air batteries and water electrolysis. The formation of different Zn-Co-S morphologies was attributed to the synergistic effect of decomposed urea products and the corrosion of NH4F. Among synthesized Zn-Co-S nanostructures, the nanoneedle arrays supported on CFP exhibit superior trifunctional activity for oxygen reduction, oxygen evolution, and hydrogen evolution reactions than its nanosheet and nanoplate counterparts through half reaction testing. It also exhibited better catalytic durability than Pt/C and RuO2. Furthermore, the Zn-Co-S nanoneedle/CFP electrode enables rechargeable Zn-air batteries with low overpotential (0.85 V), high efficiency (58.1%), and long cycling lifetimes (200 cycles) at 10 mA cm(-2) as well as considerable performance for water splitting. The superior performance is contributed to the integrated nanoneedle/CFP nanostructure, which not only provides enhanced electrochemical active area, but also facilitates ion and gas transfer between the catalyst surface and electrolyte, thus maintaining an effective solid-liquid-gas interface necessary for electrocatalysis. These results indicate that the Zn-Co-S nanoneedle/CFP system is a low cost, highly active, and durable electrode for highly efficient rechargeable zinc-air batteries and water electrolysis in alkaline solution.

  9. Migration of recharge waters downgradient from the Santa Catalina Mountains into the Tucson basin aquifer, Arizona, USA (United States)

    Cunningham, Erin E. B.; Long, Austin; Eastoe, Chris; Bassett, R. L.

    Aquifers in the arid alluvial basins of the southwestern U.S. are recharged predominantly by infiltration from streams and playas within the basins and by water entering along the margins of the basins. The Tucson basin of southeastern Arizona is such a basin. The Santa Catalina Mountains form the northern boundary of this basin and receive more than twice as much precipitation (ca. 700mm/year) as does the basin itself (ca. 300mm/year). In this study environmental isotopes were employed to investigate the migration of precipitation basinward through shallow joints and fractures. Water samples were obtained from springs and runoff in the Santa Catalina Mountains and from wells in the foothills of the Santa Catalina Mountains. Stable isotopes (δD and δ18O) and thermonuclear-bomb-produced tritium enabled qualitative characterization of flow paths and flow velocities. Stable-isotope measurements show no direct altitude effect. Tritium values indicate that although a few springs and wells discharge pre-bomb water, most springs discharge waters from the 1960s or later. Résumé La recharge des aquifères des bassins alluviaux arides du sud-ouest des États-Unis est assurée surtout à partir des lits des cours d'eau et des playas dans les bassins, ainsi que par l'eau entrant à la bordure de ces bassins. Le bassin du Tucson, dans le sud-est de l'Arizona, est l'un de ceux-ci. La chaîne montagneuse de Santa Catalina constitue la limite nord de ce bassin et reçoit plus de deux fois plus de précipitations (environ 700mm/an) que le bassin (environ 300mm/an). Dans cette étude, les isotopes du milieu ont été utilisés pour analyser le déplacement de l'eau de pluie vers le bassin au travers des fissures et des fractures proches de la surface. Des échantillons d'eau ont été prélevés dans les sources et dans l'écoulement de surface de la chaîne montagneuse et dans des puits au pied de la chaîne. Les isotopes stables (δD et δ18O) et le tritium d

  10. Quantification of groundwater recharge in urban environments. (United States)

    Tubau, Isabel; Vázquez-Suñé, Enric; Carrera, Jesús; Valhondo, Cristina; Criollo, Rotman


    Groundwater management in urban areas requires a detailed knowledge of the hydrogeological system as well as the adequate tools for predicting the amount of groundwater and water quality evolution. In that context, a key difference between urban and natural areas lies in recharge evaluation. A large number of studies have been published since the 1990s that evaluate recharge in urban areas, with no specific methodology. Most of these methods show that there are generally higher rates of recharge in urban settings than in natural settings. Methods such as mixing ratios or groundwater modeling can be used to better estimate the relative importance of different sources of recharge and may prove to be a good tool for total recharge evaluation. However, accurate evaluation of this input is difficult. The objective is to present a methodology to help overcome those difficulties, and which will allow us to quantify the variability in space and time of the recharge into aquifers in urban areas. Recharge calculations have been initially performed by defining and applying some analytical equations, and validation has been assessed based on groundwater flow and solute transport modeling. This methodology is applicable to complex systems by considering temporal variability of all water sources. This allows managers of urban groundwater to evaluate the relative contribution of different recharge sources at a city scale by considering quantity and quality factors. The methodology is applied to the assessment of recharge sources in the Barcelona city aquifers. Copyright © 2017 Elsevier B.V. All rights reserved.

  11. Biodegradation of natural organic matter in long-term, continuous-flow experiments simulating artificial ground water recharge for drinking water production. (United States)

    Kolehmainen, Reija E; Kortelainen, Nina M; Langwaldt, Jörg H; Puhakka, Jaakko A


    The role of biodegradation in the attenuation of natural organic matter (NOM) was investigated in long-term experiments that simulate artificial ground water recharge (AGR) for drinking water production. Lake water containing 5.8 mg L(-1) total organic carbon (TOC) was continuously fed into an 18.5-m-long sand column. During the 941 d of operation, on average 76 and 81% of TOC was removed within the first 0.6 m and the entire column length, respectively. Large molecular size fractions (approximately 1800-2200 Da) of NOM were removed more efficiently than smaller ones (approximately 250-1400 Da). The biodegradation of dissolved organic carbon (DOC) within the first 0.6 m, measured by the stable inorganic carbon isotope (delta13C) method, depended on temperature and hydraulic load: The extent of mineralization was 32% at 6 degrees C (Day 442) and 38% at 23 degrees C (Day 708) with a 0.3 m3 (m2d)(-1) hydraulic load and 52% at 5.5 degrees C (Day 883) with a 3.1 m3 (m2d) (-1) hydraulic load. The rest of the DOC removal was likely due to entrapment or sorption onto the sand particles. Decreases in DOC and the total cell counts in the water along the column were positively correlated (r = 0.99; P = 0.001). The accumulation of biomass was minor, with the highest concentration amounting to 7.2 mg g(-1) dw of sand. In summary, this study demonstrated that biodegradation has a key role in NOM removal in AGR and is dependent on temperature.


    The existing knowledge base regarding the presence and significance of chemicals foreign to the subsurface environment is large and growing -the papers in this volume serving as recent testament. But complex questions with few answers surround the unknowns regarding the potential for environmental or human health effects from trace levels of xenobiotics in groundwater, especially groundwater augmented with treated wastewater. Public acceptance for direct or indirect groundwater recharge using treated municipal wastewater ( especially sewage) spans the spectrum from unquestioned embrace to outright rejection. In this article, I detour around the issues most commonly discussed for groundwater recharge and instead focus on some of the less-recognized issues- those that emanate from the mysteries created at the many literal and virtual interfaces involved with the subsurface world. My major objective is to catalyze discussion that advances our understanding of the barriers to public acceptance of wastewater reuse -with its ultimate culmination in direct reuse for drinking. I pose what could be a key question as to whether much of the public's frustration or ambivalence in its decision making process for accepting or rejecting water reuse (for various purposes including personal use) emanates from fundamental inaccuracies, misrepresentation, or oversimplification of what water 'is' and how it functions in the environment -just what exactly is the 'water cyc

  13. Regional water quality patterns in an alluvial aquifer: direct and indirect influences of rivers. (United States)

    Baillieux, A; Campisi, D; Jammet, N; Bucher, S; Hunkeler, D


    The influence of rivers on the groundwater quality in alluvial aquifers can be twofold: direct and indirect. Rivers can have a direct influence via recharge and an indirect one by controlling the distribution of fine-grained, organic-carbon rich flood deposits that induce reducing conditions. These direct and indirect influences were quantified for a large alluvial aquifer on the Swiss Plateau (50km(2)) in interaction with an Alpine river using nitrate as an example. The hydrochemistry and stable isotope composition of water were characterized using a network of 115 piezometers and pumping stations covering the entire aquifer. Aquifer properties, land use and recharge zones were evaluated as well. This information provided detailed insight into the factors that control the spatial variability of groundwater quality. Three main factors were identified: (1) diffuse agricultural pollution sources; (2) dilution processes resulting from river water infiltrations, revealed by the δ(18)OH2O and δ(2)HH2O contents of groundwater; and (3) denitrification processes, controlled by the spatial variability of flood deposits governed by fluvial depositional processes. It was possible to quantify the dependence of the nitrate concentration on these three factors at any sampling point of the aquifer using an end-member mixing model, where the average nitrate concentration in recharge from the agricultural area was evaluated at 52mg/L, and the nitrate concentration of infiltrating river at approximately 6mg/L. The study shows the importance of considering the indirect and direct impacts of rivers on alluvial aquifers and provides a methodological framework to evaluate aquifer scale water quality patterns.

  14. On the interpretation of recharge estimates from steady-state model calibrations. (United States)

    Anderson, William P; Evans, David G


    Ground water recharge is often estimated through the calibration of ground water flow models. We examine the nature of calibration errors by considering some simple mathematical and numerical calculations. From these calculations, we conclude that calibrating a steady-state ground water flow model to water level extremes yields estimates of recharge that have the same value as the time-varying recharge at the time the water levels are measured. These recharge values, however, are a subdued version of the actual transient recharge signal. In addition, calibrating a steady-state ground water flow model to data collected during periods of rising water levels will produce recharge values that underestimate the actual transient recharge. Similarly, calibrating during periods of falling water levels will overestimate the actual transient recharge. We also demonstrate that average water levels can be used to estimate the actual average recharge rate provided that water level data have been collected for a sufficient amount of time.

  15. Basic aspects of the Cerro Prieto reservoir water recharge; Aspectos basicos de la recarga de agua al reservorio de Cerro Prieto

    Energy Technology Data Exchange (ETDEWEB)

    Mercado, Sergio [Instituto de Investigaciones Electricas, Cuernavaca (Mexico)


    The Cerro Prieto geothermal field, located 30 km South of Mexicali City, Baja California, has at present an installed capacity of 620 MW in geothermal power plants, that operating with endogenous steam, make use of the underground energy by means of deep wells, from which about 80 million cubic meters per year of high enthalpy water and steam mixture are extracted. During the exploitation physical an chemical changes in the hydrothermal fluids discharged by the wells have been detected, which shows, among other things, an elevated water recharge, located towards the West area of the field and a low recharge in the part of the east zone area. For this reason the hot brine waste re-injection is recommended, (previously treated to eliminate the silica excess) to thermally an hydraulically recharge the reservoir in that part of the field. [Espanol] El campo geotermico de Cerro Prieto, situado a 30 km al sur de la ciudad de Mexicali, Baja California, cuenta actualmente, despues de 18 anos en explotacion, con 620 MW de capacidad instalada en plantas geotermoelectricas que, operando con vapor endogeno, aprovechan la energia del subsuelo mediante pozos profundos de los que se extraen alrededor de 80 millones de metros cubicos por ano de una mezcla de agua vapor de elevada entalpia. Durante la explotacion se han percibido cambios fisicos y quimicos en los fluidos hidrotermales descargados por los pozos, lo que indica, entre otras cosas, una recarga elevada de agua localizada hacia el poniente del campo y una recarga baja en una zona de la parte oriental. Por ello se recomienda la reinyeccion de salmuera geotermica caliente de desecho (previamente tratada para eliminar el exceso de silice) para recargar termica e hidraulicamente el reservorio en esa parte del campo.

  16. Automating Recession Curve Displacement Recharge Estimation. (United States)

    Smith, Brennan; Schwartz, Stuart


    Recharge estimation is an important and challenging element of groundwater management and resource sustainability. Many recharge estimation methods have been developed with varying data requirements, applicable to different spatial and temporal scales. The variability and inherent uncertainty in recharge estimation motivates the recommended use of multiple methods to estimate and bound regional recharge estimates. Despite the inherent limitations of using daily gauged streamflow, recession curve displacement methods provide a convenient first-order estimate as part of a multimethod hierarchical approach to estimate watershed-scale annual recharge. The implementation of recession curve displacement recharge estimation in the United States Geologic Survey (USGS) RORA program relies on the subjective, operator-specific selection of baseflow recession events to estimate a gauge-specific recession index. This paper presents a parametric algorithm that objectively automates this tedious, subjective process, parameterizing and automating the implementation of recession curve displacement. Results using the algorithm reproduce regional estimates of groundwater recharge from the USGS Appalachian Valley and Piedmont Regional Aquifer-System Analysis, with an average absolute error of less than 2%. The algorithm facilitates consistent, completely automated estimation of annual recharge that complements more rigorous data-intensive techniques for recharge estimation. © 2016, National Ground Water Association.

  17. Characteristics of groundwater recharge on the North China Plain. (United States)

    Tan, Xiu-Cui; Wu, Jing-Wei; Cai, Shu-Ying; Yang, Jin-Zhong


    Groundwater recharge is an important component of the groundwater system. On the North China Plain (NCP), groundwater is the main water supply. Because of large-scale overexploitation, the water table has declined, which has produced severe adverse effects on the environment and ecosystem. In this article, tracer experiment and watershed model were used to calculate and analyze NCP groundwater recharge. In the tracer experiment, average recharge was 108 mm/year and recharge coefficient 0.16. With its improved irrigation, vegetation coverage and evapotranspiration modules, the INFIL3.0 model was used for calculation of groundwater recharge. Regional modeling results showed an average recharge of 102 mm/year and recharge coefficient 0.14, for 2001-2009. These values are very similar to those from the field tracer experiment. Influences in the two methods were analyzed. The results can provide an important reference for NCP groundwater recharge.

  18. Groundwater recharge assessment at local and episodic scale in a soil mantled perched karst aquifer in southern Italy (United States)

    Allocca, V.; De Vita, P.; Manna, F.; Nimmo, J. R.


    Groundwater recharge assessment of karst aquifers, at various spatial and temporal scales, is a major scientific topic of current importance, since these aquifers play an essential role for both socio-economic development and fluvial ecosystems. In this study, groundwater recharge was estimated at local and episodic scales in a representative perched karst aquifer in a region of southern Italy with a Mediterranean climate. The research utilized measurements of precipitation, air temperature, soil water content, and water-table depth, obtained in 2008 at the Acqua della Madonna test area (Terminio Mount karst aquifer, Campania region). At this location the aquifer is overlain by ash-fall pyroclastic soils. The Episodic Master Recession (EMR) method, an improved version of the Water Table Fluctuation (WTF) method, was applied to estimate the amount of recharge generated episodically by individual rainfall events. The method also quantifies the amount of precipitation generating each recharge episode, thus permitting calculation of the Recharge to the Precipitation Ratio (RPR) on a storm-by-storm basis. Depending on the seasonally varying air temperature, evapotranspiration, and precipitation patterns, calculated values of RPR varied between 35% and 97% among the individual episodes. A multiple linear correlation of the RPR with both the average intensity of recharging rainfall events and the antecedent soil water content was calculated. Given the relatively easy measurability of precipitation and soil water content, such an empirical model would have great hydrogeological and practical utility. It would facilitate short-term forecasting of recharge in karst aquifers of the Mediterranean region and other aquifers with similar hydrogeological characteristics. By establishing relationships between the RPR and climate-dependent variables such as average storm intensity, it would facilitate prediction of climate-change effects on groundwater recharge. The EMR methodology

  19. Availability of Surface Water of Wadi Rajil as a Source of Groundwater Artificial Recharge: A Case Study of Eastern Badia /Jordan

    Directory of Open Access Journals (Sweden)

    Rakad A. Ta'any


    Full Text Available Wadi Rajil catchment area is considered as one of the major wadis entering the Azraq Basin from the north. It is ungauged wadi and covers an area of about 3910km2. The annual average rainfall on Wadi Rajil catchment area is about 126.6mm. Heavy thunderstorms occur in April and May, causing significant floods covering the area. The flood waters are not utilized, and a small portion infiltrates into the ground, where the great portion of these waters remain over Qaa’ Azraqfew months before evaporation. Due to the absence of the hydrometric stream flow station, no data are available about surface water runoff in Wadi Rajil catchment area. Therefore, the first part of this study calculates the surface water potential of Wadi Rajil to be utilized for groundwater artificial recharge, applying the SCS curvilinear synthetic unit hydrograph method. The synthesis unit hydrograph of Wadi Rajil catchment is characterized by a peak value of 1146 m3/s (4047 cfs per one inch of rainfall excess. Flood hydrographs for 10,25,50, and 100 years return periods were derived and their peak flow are found to be 10,8,186,412, and 680 m3/s, respectively and the corresponding flood volumes are 0.95, 16.53, 36.89, and 61.5 MCM, respectively.Groundwater artificial recharge conditions are suitably prevailing in the most northern and central part of the catchment area, whereas, geological, Hydrogeological, and water quality characteristics of the floodwater encourage artificial replenishment of the exploited aquifer in the study area.

  20. 北京市深井人工回灌现状调查与前景分析%Current situation investigation and prospect analysis of artificaial recharge of ground water in Beijing city

    Institute of Scientific and Technical Information of China (English)

    孙颖; 苗礼文


    北京市地下水人工回灌研究始于1965年。1981年开始生产性深井人工回灌。由于种种原因,至1999年底实际回灌单位由64个缩减至13个。其间累计回灌量为10734.37×104t。据调查,停灌原因主要有:回灌单位停产、转产、回灌井被占,回灌井阻塞,泵改调频,单位搬迁和改换制冷设备等。本文通过对北京市三十几年来地下水人工回灌工作的总结,分析了人工回灌在近年来发展停滞的原因,并对其在城市可持续发展建设中的节水潜力和今后的发展前景作出了论述。%The study of artificial recharge of ground water in Beijing City started in 1965,and the productive well recharge began in 1981.Due to various reasons,by the end of 1999,the number of artificial recharge units decreased to 13 from 64 at the beginning.The total recharge adds up to 107,343,700 over the period.Investigation result indicates that the main reasons for the stagnation are:Some recharge units stopped production,or switched to other production;Some recharge wells were blocked or taken over for other purposes;Change of location or reconstruction of the refrigeration facilities of the recharge units.This article concluded the artificial recharge of ground water of Beijing City over the past more than thirty years,and analyzed the reason why the development of artifiial recharge has been stagnated in recent years.The water saving potential of artificial recharge during the sustainable development and construction of the city and the prospect of development in the future are expounded.

  1. Vanadium Pentoxide-Based Composite Synthesized Using Microwave Water Plasma for Cathode Material in Rechargeable Magnesium Batteries

    Directory of Open Access Journals (Sweden)

    Tatsuhiko Yajima


    Full Text Available Multivalent cation rechargeable batteries are expected to perform well as high-capacity storage devices. Rechargeable magnesium batteries have an advantage in terms of resource utilization and safety. Here, we report on sulfur-doped vanadium pentoxide (S-V2O5 as a potential material for the cathodes of such a battery; S-V2O5 showed a specific capacity of 300 mAh·g−1. S-V2O5 was prepared by a method using a low-temperature plasma generated by carbon felt and a 2.45 GHz microwave generator. This study investigates the ability of S-V2O5 to achieve high capacity when added to metal oxide. The highest recorded capacity (420 mAh·g−1 was reached with MnO2 added to composite SMn-V2O5, which has a higher proportion of included sulfur than found in S-V2O5. Results from transmission electron microscopy, energy-dispersive X-ray spectroscopy, Micro-Raman spectroscopy, and X-ray photoelectron spectroscopy show that the bulk of the SMn-V2O5 was the orthorhombic V2O5 structure; the surface was a xerogel-like V2O5 and a solid solution of MnO2 and sulfur.

  2. Lepini Mountains Carbonatic Ridge: try of springs recharge areas verification and water exchange quantification with Pontina Plain by use of a numerical model (Central Italy

    Directory of Open Access Journals (Sweden)

    Pamela Teoli


    Full Text Available The study area of this work is represented by the Lepini Mountains carbonatic ridge and by the Pontina Plain foothills area, on which in the past, within quantitative hydrogeological characterizations, models were developed for calculating the groundwater flow, but only referred to the ridge. The most recent studies (Teoli, 2012 have done their best, instead, to represent the underground water exchanges between the ridge and the Pontina Plain foothill area. The new model (developed using computer code MODFLOW 2005 has been implemented to simulate steady-state underground flow using equivalent porous media approach even for the ridge; attention has been particularly directed to the proper tectonic ridge schematic, which the authors had previously defined, together with others (Alimonti et al., 2010, on detailed structural-geological survey basis, integrated by hydrogeological analysis. So, it’s been possible to determine partitioning effects on groundwater flowpaths and on springs recharge areas extent, whose total average discharge is about 10m3/s. Model calibration main goal has been the recharge areas permeability definition, posing the correspondence of calculated flows with measured springs’ flows; as a consequence, it’s been possible to improve the model reliability (uncertainty reduction quantifying the flow residuals’ standard deviation offset.

  3. Quantifying the Effect of Thinning Vegetation on Evapotranspiration in a Mountainous Watershed through Remote Sensing: Improving Water Balance Estimates for Managed Aquifer Recharge (United States)

    Revelle, P.; Hendrickx, J. M. H.


    A long-term water balance study in an experimental watershed of the Sacramento Mountains in New Mexico monitors the impact of thinning vegetation on groundwater recharge. The study objective is to evaluate if thinning forest vegetation will increase groundwater recharge in the mountains to provide larger regional flows to aquifers in surrounding basins. In the semi-arid Southwest, evapotranspiration (ET) makes up 75 to 95% or more of the total water budget. The variability of daily vegetation transpiration and solar radiation with time of year and the effects of complex terrain create a seasonal and spatial variability of ET that is not well quantified in mountainous regions. Through applying the remote sensing model METRIC (Mapping Evapotranspiration with High Resolution and Internalized Calibration) to satellite imagery from the LANDSAT satellite, we calculate high-resolution maps of ET for the Sacramento Mountains watershed area to quantify spatially-distributed estimates of ET before and after thinning to provide improved estimates for determining the water balance and the effect on recharge. METRIC calculates ET through applying an energy balance spatially across an image to estimate ET for each pixel (30m x 30m). Differences in ET are calculated between thinned and control plots in the watershed before and after thinning with the net impact of thinning on ET for an image determined with standard statistical tests following a Before-After Control-Impact (BACI) approach commonly used in environmental impact assessment studies. Estimates of ET from METRIC indicate a net decrease in ET in the first year after thinning for all of the thinned plots but show significant variability (~2 - 12 %) between areas with different terrain characteristics. The impact of surface parameters such as slope, aspect, or albedo among others are currently being examined using multivariate statistical analysis methods to improve the understanding of the spatial and temporal

  4. Oxygen and Hydrogen Isotopes of Waters in the Ordos Basin,China: Implications for Recharge of Groundwater in the North of Cretaceous Groundwater Basin

    Institute of Scientific and Technical Information of China (English)

    YANG Yuncheng; SHEN Zhaoli; WENG Dongguang; HOU Guangcai; ZHAO Zhenhong; WANG Dong; PANG Zhonghe


    Hundreds of precipitation samples collected from meteorological stations in the Ordos Basin from January 1988 to December 2005 were used to set up a local meteoric water line and to calculate weighted average isotopic compositions of modern precipitation.Oxygen and hydrogen isotopes, with and gradually decrease in summer and fall,illustrating that the seasonal effect is considerable.They also show that the isotopic difference between south portion and north portion of the Ordos Basin are not obvious.and the isotope in the middle portion iS normally depleted.The isotope compositions of 32 samples collected from shallow groundwater(less than a depth of 150 m)in desert plateau range from for JD.Most of them are identical with modern precipitation.The isotope compositions of 22 middle and deep groundwaters(greater than a depth of 275 m)fall in ranges from-11.6‰to-8.8‰with an average of-10.2‰ for £18O and from-89‰ to-63‰ with an average of-76‰ for £D.The average values are significantly less than those of modern precipitation,illustrating that the middle and deep groundwaters were recharged at comparatively lower air temperatures.Primary analysis of 14C shows that the recharge of the middle and deep groundwaters started at late Pleistocene.The isotopes of 13 lake water samples collected from eight lakes define a local evaporation trend,with a relatively flat slope of 3.77,and show that the lake waters were mainly fed by modern precipitation and shallow groundwater.

  5. Rechargeable calcium phosphate orthodontic cement with sustained ion release and re-release (United States)

    Zhang, Ling; Weir, Michael D.; Chow, Laurence C.; Reynolds, Mark A.; Xu, Hockin H. K.


    White spot lesions (WSL) due to enamel demineralization are major complications for orthodontic treatments. Calcium phosphate (CaP) dental resins with Ca and P ion releases are promising for remineralization. However, previous Ca and P releases lasted for only weeks. Experimental orthodontic cements were developed using pyromellitic glycerol dimethacrylate (PMGDM) and ethoxylated bisphenol A dimethacrylate (EBPADMA) at mass ratio of 1:1 (PE); and PE plus 10% of 2-hydroxyethyl methacrylate (HEMA) and 5% of bisphenol A glycidyl dimethacrylate (BisGMA) (PEHB). Particles of amorphous calcium phosphate (ACP) were incorporated into PE and PEHB at 40% filler level. Specimens were tested for bracket-enamel shear bond strength, water sorption, CaP release, and ion recharge and re-release. PEHB+40ACP had higher bracket-enamel bond strength and ion release and rechargeability than PE+40ACP. ACP incorporation into the novel orthodontic cement did not adversely affect the bracket-enamel bond strength. Ion release and re-release from the novel ACP orthodontic cement indicated favorable release and re-release patterns. The recharged orthodontic cement could release CaP ions continuously for four weeks without further recharge. Novel rechargeable orthodontic cement containing ACP was developed with a high bracket-enamel bond strength and the ability to be repeatedly recharged to maintain long-term high levels of CaP ion releases.

  6. Quality of surface-water runoff in selected streams in the San Antonio segment of the Edwards aquifer recharge zone, Bexar County, Texas, 1997-2012 (United States)

    Opsahl, Stephen P.


    During 1997–2012, the U.S. Geological Survey, in cooperation with the San Antonio Water System, collected and analyzed water-quality constituents in surface-water runoff from five ephemeral stream sites near San Antonio in northern Bexar County, Texas. The data were collected to assess the quality of surface water that recharges the Edwards aquifer. Samples were collected from four stream basins that had small amounts of developed land at the onset of the study but were predicted to undergo substantial development over a period of several decades. Water-quality samples also were collected from a fifth stream basin located on land protected from development to provide reference data by representing undeveloped land cover. Water-quality data included pH, specific conductance, chemical oxygen demand, dissolved solids (filtered residue on evaporation in milligrams per liter, dried at 180 degrees Celsius), suspended solids, major ions, nutrients, trace metals, and pesticides. Trace metal concentration data were compared to the Texas Commission on Environmental Quality established surface water quality standards for human health protection (water and fish). Among all constituents in all samples for which criteria were available for comparison, only one sample had one constituent which exceeded the surface water criteria on one occasion. A single lead concentration (2.76 micrograms per liter) measured in a filtered water sample exceeded the surface water criteria of 1.15 micrograms per liter. The average number of pesticide detections per sample in stream basins undergoing development ranged from 1.8 to 6.0. In contrast, the average number of pesticide detections per sample in the reference stream basin was 0.6. Among all constituents examined in this study, pesticides, dissolved orthophosphate phosphorus, and dissolved total phosphorus demonstrated the largest differences between the four stream basins undergoing development and the reference stream basin with

  7. Macroscopic Thermal Energy Balance on Montane Valley Aquifers and Groundwater Recharge Source Identification (United States)

    Trask, J. C.; Fogg, G. E.


    Several recent publications have highlighted the need to improve definition of groundwater flow patterns in montane regions, presenting case studies with several field investigative approaches. Determination of the depth of upland bedrock groundwater circulation and identification of valley aquifer recharge sources in montane areas is needed for improved characterization of montane groundwater flow patterns and for aquifer source protection planning. In most upland bedrock regions, wells and boreholes are scarce, adding to the challenges inherent to investigating groundwater flow in fractured rock systems. Approaches using natural environmental tracers have previously been shown to be effective in quantifying subsurface recharge into valley aquifers from groundwater flow within adjoining mountain-front and mountain-block areas. Thermal tracing of montane groundwater flow is easy and inexpensive relative to other environmental tracer and geophysical techniques, and can complement other approaches (e.g. Manning and Solomon, 2005). We present a heat flow tracer approach to identification of montane valley aquifer recharge sources. A novel application of a macroscopic thermal energy balance is introduced and used in recharge source analysis for two mountain-front bounding basin-fill aquifers located in the Sierra Nevada, USA. We show that robust upper and lower bounds on total heat flow and sources of recharge into montane valley aquifers may be determined without numerical modeling by using a macroscopic thermal energy balance. Several factors tend to enhance focusing of geothermal conductive heat flow from depth toward montane valley margins. Analytic bracketing techniques, applicable to domains with irregular boundary geometry and non-uniform thermal boundary conditions, are used together with thermal data to obtain quantitative bounds on conductive heat flow across aquifer domain boundaries. Thermal data required include: (i) a rough estimate of regional geothermal

  8. Artificial recharge of groundwater: hydrogeology and engineering (United States)

    Bouwer, Herman


    Artificial recharge of groundwater is achieved by putting surface water in basins, furrows, ditches, or other facilities where it infiltrates into the soil and moves downward to recharge aquifers. Artificial recharge is increasingly used for short- or long-term underground storage, where it has several advantages over surface storage, and in water reuse. Artificial recharge requires permeable surface soils. Where these are not available, trenches or shafts in the unsaturated zone can be used, or water can be directly injected into aquifers through wells. To design a system for artificial recharge of groundwater, infiltration rates of the soil must be determined and the unsaturated zone between land surface and the aquifer must be checked for adequate permeability and absence of polluted areas. The aquifer should be sufficiently transmissive to avoid excessive buildup of groundwater mounds. Knowledge of these conditions requires field investigations and, if no fatal flaws are detected, test basins to predict system performance. Water-quality issues must be evaluated, especially with respect to formation of clogging layers on basin bottoms or other infiltration surfaces, and to geochemical reactions in the aquifer. Clogging layers are managed by desilting or other pretreatment of the water, and by remedial techniques in the infiltration system, such as drying, scraping, disking, ripping, or other tillage. Recharge wells should be pumped periodically to backwash clogging layers. Electronic supplementary material to this paper can be obtained by using the Springer LINK server located at

  9. Enhanced recharge rates and altered recharge sensitivity to climate variability through subsurface heterogeneity (United States)

    Hartmann, Andreas; Gleeson, Tom; Wada, Yoshihide; Wagener, Thorsten


    Karst aquifers in Europe are an important source of fresh water contributing up to half of the total drinking water supply in some countries. Karstic groundwater recharge is one of the most important components of the water balance of karst systems as it feeds the karst aquifers. Presently available large-scale hydrological models do not consider karst heterogeneity adequately. Projections of current and potential future groundwater recharge of Europe's karst aquifers are therefore unclear. In this study we compare simulations of present (1991-2010) and future (2080-2099) recharge using two different models to simulate groundwater recharge processes. One model includes karst processes (subsurface heterogeneity, lateral flow and concentrated recharge), while the other is based on the conceptual understanding of common hydrological systems (homogeneous subsurface, saturation excess overland flow). Both models are driven by the bias-corrected 5 GCMs of the ISI-MIP project (RCP8.5). To further assess sensitivity of groundwater recharge to climate variability, we calculate the elasticity of recharge rates to annual precipitation, temperature and average intensity of rainfall events, which is the median change of recharge that corresponds to the median change of these climate variables within the present and future time period, respectively. Our model comparison shows that karst regions over Europe have enhanced recharge rates with greater inter-annual variability compared to those with more homogenous subsurface properties. Furthermore, the heterogeneous representation shows stronger elasticity concerning climate variability than the homogeneous subsurface representation. This difference tends to increase towards the future. Our results suggest that water management in regions with heterogeneous subsurface can expect a higher water availability than estimated by most of the current large-scale simulations, while measures should be taken to prepare for increasingly

  10. Rechargeable batteries applications handbook

    CERN Document Server


    Represents the first widely available compendium of the information needed by those design professionals responsible for using rechargeable batteries. This handbook introduces the most common forms of rechargeable batteries, including their history, the basic chemistry that governs their operation, and common design approaches. The introduction also exposes reader to common battery design terms and concepts.Two sections of the handbook provide performance information on two principal types of rechargeable batteries commonly found in consumer and industrial products: sealed nickel-cad

  11. Natural vs. artificial groundwater recharge, quantification through inverse modeling

    Directory of Open Access Journals (Sweden)

    H. Hashemi


    Full Text Available Estimating the change in groundwater recharge from an introduced artificial recharge system is important in order to evaluate future water availability. This paper presents an inverse modeling approach to quantify the recharge contribution from both an ephemeral river channel and an introduced artificial recharge system based on floodwater spreading in arid Iran. The study used the MODFLOW-2000 to estimate recharge for both steady- and unsteady-state conditions. The model was calibrated and verified based on the observed hydraulic head in observation wells and model precision, uncertainty, and model sensitivity were analyzed in all modeling steps. The results showed that in a normal year without extreme events, the floodwater spreading system is the main contributor to recharge with 80% and the ephemeral river channel with 20% of total recharge in the studied area. Uncertainty analysis revealed that the river channel recharge estimation represents relatively more uncertainty in comparison to the artificial recharge zones. The model is also less sensitive to the river channel. The results show that by expanding the artificial recharge system, the recharge volume can be increased even for small flood events, while the recharge through the river channel increases only for major flood events.

  12. Tongue pressure patterns during water swallowing. (United States)

    Kennedy, Daniel; Kieser, Jules; Bolter, Chris; Swain, Michael; Singh, Bhavia; Waddell, J Neil


    Bolus propulsion during the normal oral phase of swallowing is thought to be characterised by the sequential elevation of the front, middle, and posterior regions of the dorsum of the tongue. However, the coordinated orchestration of lingual movement is still poorly understood. This study examined how pressures generated by the tongue against the hard palate differed between three points along the midline of the tongue. Specifically, we tested three hypotheses: (1) that there are defined individual patterns of pressure change within the mouth during liquid swallowing; (2) that there are significant negative pressures generated at defined moments during normal swallowing; and, (3) that liquid swallowing is governed by the interplay of pressures generated in an anteroposterior direction in the mouth. Using a metal appliance described previously, we measured absolute pressures during water swallows in six healthy volunteers (4 male, 2 female) with an age range of 25-35 years. Participants performed three 10-ml water swallows from a small cup on five separate days, thus providing data for a total of 15 separate water swallows. There was a distinct pattern to the each of the pressure signals, and this pattern was preserved in the mean obtained when the data were pooled. Furthermore, raw signals from the same subjects presented consistent patterns at each of the five testing sessions. In all subjects, pressure at the anterior and hind palate tended to be negative relative to the preswallow value; at mid-palate, however, pressure changes were less consistent between individuals. When the pressure differences between the sites were calculated, we found that during the swallow a net negative pressure difference developed between anterior and mid-palate and a net positive pressure difference developed between mid-palate and hind palate. Large, rapid fluctuations in pressure occurred at all sites and these varied several-fold between subjects. When the brief sharp reduction

  13. Borehole environmental tracers for evaluating net infiltration and recharge through desert bedrock (United States)

    Heilweil, V.M.; Solomon, D.K.; Gardner, P.M.


    Permeable bedrock aquifers in arid regions are being increasingly developed as water supplies, yet little is generally known about recharge processes and spatial and temporal variability. Environmental tracers from boreholes were used in this study to investigate net infiltration and recharge to the fractured Navajo Sandstone aquifer. Vadose zone tracer profiles at the Sand Hollow study site in southwestern Utah look similar to those of desert soils at other sites, indicating the predominance of matrix flow. However, recharge rates are generally higher in the Navajo Sandstone than in unconsolidated soils in similar climates because the sandstone matrix allows water movement but not root penetration. Water enters the vadose zone either as direct infiltration of precipitation through exposed sandstone and sandy soils or as focused infiltration of runoff. Net infiltration and recharge exhibit extreme spatial variability. High-recharge borehole sites generally have large amounts of vadose zone tritium, low chloride concentrations, and small vadose zone oxygen-18 evaporative shifts. Annual net-infiltration and recharge rates at different locations range from about 1 to 60 mm as determined using vadose zone tritium, 0 to 15 mm using vadose zone chloride, and 3 to 60 mm using groundwater chloride. Environmental tracers indicate a cyclical net-infiltration and recharge pattern, with higher rates earlier in the Holocene and lower rates during the late Holocene, and a return to higher rates during recent decades associated with anomalously high precipitation during the latter part of the 20th century. The slightly enriched stable isotopic composition of modern groundwater indicates this recent increase in precipitation may be caused by a stronger summer monsoon or winter southern Pacific El Nin??o storm track. ?? Soil Science Society of America.

  14. Simulating Groundwater Recharge Across the Southern High Plains (United States)

    Smidt, S. J.; Haacker, E. M.; Kendall, A. D.; Hyndman, D. W.


    Quantifying recharge and water availability across the Southern High Plains is a difficult, but necessary, challenge for future groundwater and agricultural projections. Overland flow is not common due to limited precipitation, dry soils, and high evapotranspiration. The majority of runoff is temporarily stored in playa lakes, leading to the bulk of recharge across the region occurring in localized infiltration zones beneath these lakes. Despite the importance of regional recharge estimates, limited information exists that integrates complex characteristics of the land, climate, and hydrology in order to quantify recharge across the entire Southern High Plains aquifer. This study applies the Landscape Hydrology Model (LHM) to capture these characteristics and simulate surface water flow and groundwater recharge. This model simulates the complete water cycle across large regions, including irrigation estimates, establishing a framework to estimate recharge and groundwater availability in the Southern High Plains region. Results from this study can be used to predict the likely impacts of climate change and improve water management strategies.

  15. The Role of Science in Managed Aquifer Recharge--the Equus Beds aquifer near Wichita, Kansas Andrew Ziegler, Director Brian Kelly, Office Chief Michael Jacobs, Manager of Water Planning and Production Debra Ary, Engineer, Water Systems Planning (Invited) (United States)

    Ziegler, A. C.; Jacobs, M.; Ary, D.; Kelly, B.


    Data collection and interpretation using statistical, geochemical, and numerical simulation tools are essential parts of a long-term cooperative study between the city of Wichita, U.S. Geological Survey, and others to describe water quantity and quality conditions in a 165 square-mile part of the Equus Beds aquifer and Arkansas and Little Arkansas Rivers. The Equus Beds aquifer, eastern part of the High Plains Aquifer in south-central Kansas, is a vital water resource for agriculture and city of Wichita. Withdrawals for public supply began in the 1940s and agricultural irrigation began in the 1950-60s. These withdrawals led to water-level declines of up to 40 feet (historic low in 1993), a storage loss of 250,000 acre feet compared to predevelopment, and may enhance movement of chloride contamination from a past oilfield disposal area near Burrton and from natural chloride along the Arkansas River. Monitoring data and modeling show chloride near Burrton moved about 3 miles in 45 years, is about 1 mile away from the nearest public supply wells, and will continue to move for decades to centuries making the water unusable for irrigation or water supply without treatment. These concerns led to development of Wichita's 1993 integrated local water-supply plan that increased use of Cheney Reservoir and implemented aquifer storage and recovery (ASR) within the aquifer using high flows from the Little Arkansas River. ASR benefits include replacing depleted storage and slowing chloride movement. Decreased withdrawals, increased precipitation, and artificial recharge increased water levels and added 100,000 acre feet of storage through 2010, but drought since 2011 has increased withdrawals. A calibrated model will be used to simulate transport of chloride under several withdrawal scenarios using MODFLOW coupled with SEAWAT. Since 1995, water-quality data collection for more than 400 organic and inorganic compounds in surface water, treated source water for artificial recharge

  16. Patterns of local and nonlocal water resource use across the western U.S. determined via stable isotope intercomparisons (United States)

    Good, Stephen P.; Kennedy, Casey D.; Stalker, Jeremy C.; Chesson, Lesley A.; Valenzuela, Luciano O.; Beasley, Melanie M.; Ehleringer, James R.; Bowen, Gabriel. J.


    In the western U.S., the mismatch between public water demands and natural water availability necessitates large interbasin transfers of water as well as groundwater mining of fossil aquifers. Here we identify probable situations of nonlocal water use in both space and time based on isotopic comparisons between tap waters and potential water resources within hydrologic basins. Our approach, which considers evaporative enrichment of heavy isotopes during storage and distribution, is used to determine the likelihood of local origin for 612 tap water samples collected from across the western U.S. We find that 64% of samples are isotopically distinct from precipitation falling within the local hydrologic basin, a proxy for groundwater with modern recharge, and 31% of samples are isotopically distinct from estimated surface water found within the local basin. Those samples inconsistent with local water sources, which we suggest are likely derived from water imported from other basins or extracted from fossil aquifers, are primarily clustered in southern California, the San Francisco Bay area, and central Arizona. Our isotope-based estimates of nonlocal water use are correlated with both hydrogeomorphic and socioeconomic properties of basins, suggesting that these factors exert a predictable influence on the likelihood that nonlocal waters are used to supply tap water. We use these basin properties to develop a regional model of nonlocal water resource use that predicts (r2 = 0.64) isotopically inferred patterns and allows assessment of total interbasin transfer and/or fossil aquifer extraction volumes across the western U.S.

  17. The fate of H2O2 during managed aquifer recharge: A residual from advanced oxidation processes for drinking water production. (United States)

    Wang, F; van Halem, D; van der Hoek, J P


    The fate of H2O2 residual from advanced oxidation process (AOP) preceding managed aquifer recharge (MAR) is of concern because H2O2 could lead to undesired effects on organisms in the MAR aquatic and soil ecosystem. The objective of this study was to distinguish between factors affecting H2O2 decomposition in MAR systems, simulated in batch reactors with synthetic MAR water and slow sand filter sand. The results showed that pure sand and soil organic matter had no considerable effect on H2O2 decomposition, whereas naturally occurring inorganic substances on the surface of sand grains and microbial biomass are the two main factors accelerating H2O2 decomposition in MAR systems. Additionally, the results showed that the H2O2 decompositions with different initial concentrations fitted first-order kinetics in 2-6 h in a mixture of slow sand filter sand (as a substitute for sand from a MAR system) and synthetic MAR water with high bacterial population. An estimation indicated that low concentrations of H2O2 (water containing high microbial biomass 38 ng ATP/mL. Copyright © 2016 Elsevier Ltd. All rights reserved.

  18. Evaluation of Groundwater Recharge Estimates in a Partially Metamorphosed Sedimentary Basin in a Tropical Environment: Application of Natural Tracers (United States)

    Oteng Mensah, Felix; Alo, Clement


    This study tests the representativeness of groundwater recharge estimates through the chloride mass balance (CMB) method in a tropical environment. The representativeness of recharge estimates using this methodology is tested using evaporation estimates from isotope data, the general spatial distribution of the potential field, and the topographical variations in the area. This study suggests that annual groundwater recharge rates in the area ranges between 0.9% and 21% of annual precipitation. These estimates are consistent with evaporation rates computed from stable isotope data of groundwater and surface water in the Voltaian Basin. Moreover, estimates of groundwater recharge through numerical model calibration in other parts of the terrain appear to be consistent with the current data in this study. A spatial distribution of groundwater recharge in the area based on the estimated data takes a pattern akin to the spatial pattern of distribution of the hydraulic head, the local topography, and geology of the terrain. This suggests that the estimates at least qualitatively predicts the local recharge and discharge locations in the terrain. PMID:24772021

  19. Using isotopes of dissolved inorganic carbon species and water to separate sources of recharge in a cave spring, northwestern Arkansas, USA Blowing Spring Cave (United States)

    Knierim, Katherine Joy; Pollock, Erik; Hays, Phillip D.


    Blowing Spring Cave in northwestern Arkansas is representative of cave systems in the karst of the Ozark Plateaus, and stable isotopes of water (δ18O and δ2H) and inorganic carbon (δ13C) were used to quantify soil-water, bedrock-matrix water, and precipitation contributions to cave-spring flow during storm events to understand controls on cave water quality. Water samples from recharge-zone soils and the cave were collected from March to May 2012 to implement a multicomponent hydrograph separation approach using δ18O and δ2H of water and dissolved inorganic carbon (δ13C–DIC). During baseflow, median δ2H and δ18O compositions were –41.6‰ and –6.2‰ for soil water and were –37.2‰ and –5.9‰ for cave water, respectively. Median DIC concentrations for soil and cave waters were 1.8 mg/L and 25.0 mg/L, respectively, and median δ13C–DIC compositions were –19.9‰ and –14.3‰, respectively. During a March storm event, 12.2 cm of precipitation fell over 82 h and discharge increased from 0.01 to 0.59 m3/s. The isotopic composition of precipitation varied throughout the storm event because of rainout, a change of 50‰ and 10‰ for δ2H and δ18O was observed, respectively. Although, at the spring, δ2H and δ18O only changed by approximately 3‰ and 1‰, respectively. The isotopic compositions of precipitation and pre-event (i.e., soil and bedrock matrix) water were isotopically similar and the two-component hydrograph separation was inaccurate, either overestimating (>100%) or underestimating (<0%) the precipitation contribution to the spring. During the storm event, spring DIC and δ13C–DIC decreased to a minimum of 8.6 mg/L and –16.2‰, respectively. If the contribution from precipitation was assumed to be zero, soil water was found to contribute between 23 to 72% of the total volume of discharge. Although the assumption of negligible contributions from precipitation is unrealistic, especially in karst systems where rapid flow

  20. The effect of hydrogeological conditions on variability and dynamic of groundwater recharge in a carbonate aquifer at local scale (United States)

    Dvory, Noam Zach; Livshitz, Yakov; Kuznetsov, Michael; Adar, Eilon; Yakirevich, Alexander


    Groundwater recharge in fractured karstic aquifers is particularly difficult to quantify due to the rock mass's heterogeneity and complexity that include preferential flow paths along karst conduits. The present study's major goals were to assess how the changes in lithology, as well as the fractured karst systems, influence the flow mechanism in the unsaturated zone, and to define the spatial variation of the groundwater recharge at local scale. The study area is located within the fractured carbonate Western Mountain aquifer (Yarkon-Taninim), west of the city of Jerusalem at the Ein Karem (EK) production well field. Field monitoring included groundwater level observations in nine locations in the study area during years 1990-2014. The measured groundwater level series were analyzed with the aid of one-dimensional, dual permeability numerical model of water flow in variably saturated fractured-porous media, which was calibrated and used to estimate groundwater recharge at nine locations. The recharge values exhibit significant spatial and temporal variation with mean and standard deviation values of 216 and 113 mm/year, respectively. Based on simulations, relationships were established between precipitation and groundwater recharge in each of the nine studied sites and compared with similar ones obtained in earlier regional studies. Simulations show that fast and slow flow paths conditions also influence annual cumulative groundwater recharge dynamic. In areas where fast flow paths exist, most of the groundwater recharge occurs during the rainy season (60-80% from the total recharge for the tested years), while in locations with slow flow path conditions the recharge rate stays relatively constant with a close to linear pattern and continues during summer.

  1. Groundwater recharge and agricultural contamination (United States)

    Böhlke, J.K.


    Agriculture has had direct and indirect effects on the rates and compositions of groundwater recharge and aquifer biogeochemistry. Direct effects include dissolution and transport of excess quantities of fertilizers and associated materials and hydrologic alterations related to irrigation and drainage. Some indirect effects include changes in water-rock reactions in soils and aquifers caused by increased concentrations of dissolved oxidants, protons, and major ions. Agrilcultural activities have directly or indirectly affected the concentrations of a large number of inorganic chemicals in groundwater, for example NO3-, N2, Cl, SO42-, H+, P, C, K, Mg, Ca, Sr, Ba, Ra, and As, as well a wide variety of pesticides and other organic compounds. For reactive contaminants like NO3-, a combination of chemical, isotopic, and environmental-tracer analytical approaches might be required to resolve changing inputs from subsequent alterations as causes of concentration gradients in groundwater. Groundwater records derived from multi-component hydrostratigraphic data can be used to quantify recharge rates and residence times of water and dissolved contaminants, document past variations in recharging contaminant loads, and identify natural contaminant-remediation processes. These data indicate that many of the world's surficial aquifers contain transient records of changing agricultural contamination from the last half of the 20th century. The transient agricultural groundwater signal has important implications for long-term trends and spatial heterogeneity in discharge.

  2. Modelling the effects of climate and land cover change on groundwater recharge in south-west Western Australia (United States)

    Dawes, W.; Ali, R.; Varma, S.; Emelyanova, I.; Hodgson, G.; McFarlane, D.


    The groundwater resource contained within the sandy aquifers of the Swan Coastal Plain, south west Western Australia, provides approximately 60% of the drinking water for the metropolitan population of Perth. Rainfall decline over the past three decades coupled with increasing water demand from a growing population has resulted in falling dam storage and groundwater levels. Projected future changes in climate across south-west Western Australia consistently show a decline in annual rainfall of between 5 and 15%. There is expected to be a continuing reduction of diffuse recharge across the Swan Coastal Plain. This study aims to quantify the change in groundwater recharge in response to a range of future climate and land cover patterns across south-west Western Australia. Modelling the impact on the groundwater resource of potential climate change was achieved with a dynamically linked unsaturated/saturated groundwater model. A Vertical Flux Manager was used in the unsaturated zone to estimate groundwater recharge using a variety of simple and complex models based on land cover type (e.g. native trees, plantation, cropping, urban, wetland), soil type, and taking into account the groundwater depth. These recharge estimates were accumulated on a daily basis for both observed and projected climate scenarios and used in a MODFLOW simulation with monthly stress periods. In the area centred on the city of Perth, Western Australia, the patterns of recharge change and groundwater level change are not consistent spatially, or consistently downward. In the Dandaragan Plateau to the north-east of Perth there has been groundwater level rise since the 1970s associated with land clearing, and with rainfall projected to reduce the least in this area the groundwater levels are estimated to continue to rise. Along the coastal zone north of Perth there is an interaction between projected rainfall decline and legislated removal to pine forests. This results in areas of increasing

  3. Modelling the effects of climate and land cover change on groundwater recharge in south-west Western Australia

    Directory of Open Access Journals (Sweden)

    W. Dawes


    Full Text Available The groundwater resource contained within the sandy aquifers of the Swan Coastal Plain, south west Western Australia, provides approximately 60% of the drinking water for the metropolitan population of Perth. Rainfall decline over the past three decades coupled with increasing water demand from a growing population has resulted in falling dam storage and groundwater levels. Projected future changes in climate across south-west Western Australia consistently show a decline in annual rainfall of between 5 and 15%. There is expected to be a continuing reduction of diffuse recharge across the Swan Coastal Plain. This study aims to quantify the change in groundwater recharge in response to a range of future climate and land cover patterns across south-west Western Australia.

    Modelling the impact on the groundwater resource of potential climate change was achieved with a dynamically linked unsaturated/saturated groundwater model. A Vertical Flux Manager was used in the unsaturated zone to estimate groundwater recharge using a variety of simple and complex models based on land cover type (e.g. native trees, plantation, cropping, urban, wetland, soil type, and taking into account the groundwater depth. These recharge estimates were accumulated on a daily basis for both observed and projected climate scenarios and used in a MODFLOW simulation with monthly stress periods.

    In the area centred on the city of Perth, Western Australia, the patterns of recharge change and groundwater level change are not consistent spatially, or consistently downward. In the Dandaragan Plateau to the north-east of Perth there has been groundwater level rise since the 1970s associated with land clearing, and with rainfall projected to reduce the least in this area the groundwater levels are estimated to continue to rise. Along the coastal zone north of Perth there is an interaction between projected rainfall decline and legislated removal to pine forests. This

  4. Basin-scale recharge in the Southwestern United States (United States)

    Hogan, J. F.; Duffy, C.; Eastoe, C.; Ferre, T. P. A.; Goodrich, D.; Hendrickx, J.; Hibbs, B.; Phillips, F.; Small, E.; Wilson, J.


    The major domestic water source in the arid southwestern United States is groundwater from alluvial basin aquifers. Accurate estimates of basin-scale groundwater recharge rates are a critical need for developing sustainable or "safe yield" groundwater pumping. Basin-scale recharge rates are typically estimated using inverse hydrologic modeling or geochemical tracers (e.g. chloride mass balance). These methods, while useful, have a high level of uncertainty and provide no information about the mechanisms of groundwater recharge. SAHRA - an NSF Science and Technology Center focused on the Sustainability of semi-Arid Hydrology and Riparian Areas - has developed an integrated research plan to address this problem. Our approach is two-fold. First we are investigating the "input" components that comprise basin-scale recharge: basin floor recharge, alluvial channel recharge, mountain front recharge, and mountain block recharge. Each component has unique spatial and temporal scales and thus requires distinct methods. Our research is aimed at understanding the factors (e.g. vegetation type, bedrock lithology, soil structure) that control recharge rates in each of these locations. With such an understanding one could then scale from point measurements to the basin-scale using remote sensing data. Our second approach is to employ isotopic tracers to determine water sources, groundwater ages and residence times of the groundwater and surface water "outputs"; these values can then be used to better calibrate recharge rates in groundwater models. By focusing our studies on two basins, the San Pedro River Basin in Arizona and the Rio Grande in New Mexico, we hope to develop a better understanding of the importance of different recharge pathways for basin-scale recharge and which methods are best suited for estimating basin-scale recharge.

  5. A comparison of groundwater recharge estimation methods in a semi-arid, coastal avocado and citrus orchard (Ventura County, California) (United States)

    Grismer, Mark E.; Bachman, S.; Powers, T.


    We assess the relative merits of application of the most commonly used field methods (soil-water balance (SWB), chloride mass balance (CMB) and soil moisture monitoring (NP)) to determine recharge rates in micro-irrigated and non-irrigated areas of a semi-arid coastal orchard located in a relatively complex geological environment.Application of the CMB method to estimate recharge rates was difficult owing to the unusually high, variable soil-water chloride concentrations. In addition, contrary to that expected, the chloride concentration distribution at depths below the root zone in the non-irrigated soil profiles was greater than that in the irrigated profiles. The CMB method severely underestimated recharge rates in the non-irrigated areas when compared with the other methods, although the CMB method estimated recharge rates for the irrigated areas, that were similar to those from the other methods, ranging from 42 to 141 mm/year.The SWB method, constructed for a 15-year period, provided insight into the recharge process being driven by winter rains rather than summer irrigation and indicated an average rate of 75 mm/year and 164 mm/year for the 1984 - 98 and 1996 - 98 periods, respectively. Assuming similar soil-water holding capacity, these recharge rates applied to both irrigated and non-irrigated areas. Use of the long period of record was important because it encompassed both drought and heavy rainfall years. Successful application of the SWB method, however, required considerable additional field measurements of orchard ETc, soil-water holding capacity and estimation of rainfall interception - runoff losses.Continuous soil moisture monitoring (NP) was necessary to identify both daily and seasonal seepage processes to corroborate the other recharge estimates. Measured recharge rates during the 1996 - 1998 period in both the orchards and non-irrigated site averaged 180 mm/year. The pattern of soil profile drying during the summer irrigation season, followed

  6. Quantifying macropore recharge: Examples from a semi-arid area (United States)

    Wood, W.W.; Rainwater, K.A.; Thompson, D.B.


    The purpose of this paper is to illustrate the significantly increased resolution of determining macropore recharge by combining physical, chemical, and isotopic methods of analysis. Techniques for quantifying macropore recharge were developed for both small-scale (1 to 10 km2) and regional-scale areas in and semi-arid areas. The Southern High Plains region of Texas and New Mexico was used as a representative field site to test these methods. Macropore recharge in small-scale areas is considered to be the difference between total recharge through floors of topographically dosed basins and interstitial recharge through the same area. On the regional scale, macropore recharge was considered to be the difference between regional average annual recharge and interstitial recharge measured in the unsaturated zone. Stable isotopic composition of ground water and precipitation was used us an independent estimate of macropore recharge on the regional scale. Results of this analysis suggest that in the Southern High Plains recharge flux through macropores is between 60 and 80 percent of the total 11 mm/y. Between 15 and 35 percent of the recharge occurs by interstitial recharge through the basin floors. Approximately 5 percent of the total recharge occurs as either interstitial or matrix recharge between the basin floors, representing approximately 95 percent of the area. The approach is applicable to other arid and semi-arid areas that focus rainfall into depressions or valleys.The purpose of this paper is to illustrate the significantly increased resolution of determining macropore recharge by combining physical, chemical, and isotopic methods of analysis. Techniques for quantifying macropore recharge were developed for both small-scale (1 to 10 km2) and regional-scale areas in arid and semi-arid areas. The Southern High Plains region of Texas and New Mexico was used as a representative field site to test these methods. Macropore recharge in small-scale areas is considered

  7. Focus on CSIR research in water resources: Managed aquifer recharge on the west coast north of Cape Town, South Africa

    CSIR Research Space (South Africa)

    Colvin, C


    Full Text Available The Atlantis Water Resource Management Scheme (AWRMS) located some 40 km north of Cape Town shows how insightful planning and management can expand the groundwater supply potential of a primary aquifer for bulk urban water supply. The AWRMS...

  8. Artificial recharge of the water-table aquifer in the latian volcano in Rome province; Ricarica artificiale dalla falda acquifera presente nel vulcano laziale in Provincia di Roma

    Energy Technology Data Exchange (ETDEWEB)

    Bersani, P.; Piotti, A. [Ambito Territoriale Ottimale, Lazio Centrale, Rome (Italy)


    The zone of the Latian Volcano extends in an area of about 1.500 km{sup 2} in the south-est of Rome. This area is thickly peopled, owing to the presence of many towns (Velletri, Frascati, Albano, etc.) in the central share of the volcanic edifice. Actually the volcanic edifice of Alban Hills shows in the central and higher area, a large caldera (Tuscolana-Artemisia). This caldera has a sub-circular form wide 10 km in diameter and 75 km{sup 2} in area. The excessive groundwater drawing by wells caused the depauperation of underground resources so to produce a real crisis since 1984. To restore of water balance of the aquifer of the Latian Volcano, an important contribution could be given by the artificial recharge of the higher aquifer. This recharge could be done by allowing to meteoric water to inflitrate as much as possible in the underground by realization of an artificial lake; otherwise by making a series of little infiltration-basins together with infiltration-wells. Besides the realization of the artificial lake could give back to the landscape a characteristic component present in the past centuries until very recent times. [Italian] L'area del Vulcano Laziale si estende su una superficie di circa 1500 km{sup 2} a sud-est di Roma in un'area densamente popolata per la presenza di numerosi centri urbani (Velletri, Frascati, Albano, ecc.), ubicati nella parte centrale dell'ufficio vulcanico. Attualmente l'edificio vulcanico dei Colli Albani presenta in posizione centrale un'ampia caldera sommitale con forma subcircolare, con diametro medio di circa 10 km ed estensione di circa 75 km{sup 2}. Gli eccessivi prelievi di acqua sotterranea hanno condotto ad un impoverimento della risorsa idrica fino a determinare una vera e propria crisi manifestatasi a partire dal 1984. Per riequilibrare il bilancio idrico dell'acquifero del Vulcano Laziale, un contributo significativo potrebbe provenire dalla ricarica artificiale dell

  9. The recharge process in alluvial strip aquifers in arid Namibia and implication for artificial recharge (United States)

    Sarma, Diganta; Xu, Yongxin


    Alluvial strip aquifers associated with ephemeral rivers are important groundwater supply sources that sustain numerous settlements and ecological systems in arid Namibia. More than 70 % of the population in the nation's western and southern regions depend on alluvial aquifers associated with ephemeral rivers. Under natural conditions, recharge occurs through infiltration during flood events. Due to the characteristic spatial and temporal variability of rainfall in arid regions, recharge is irregular making the aquifers challenging to manage sustainably and they are often overexploited. This condition is likely to become more acute with increasing water demand and climate change, and artificial recharge has been projected as the apparent means of increasing reliability of supply. The article explores, through a case study and numerical simulation, the processes controlling infiltration, significance of surface water and groundwater losses, and possible artificial recharge options. It is concluded that recharge processes in arid alluvial aquifers differ significantly from those processes in subhumid systems and viability of artificial recharge requires assessment through an understanding of the natural recharge process and losses from the aquifer. It is also established that in arid-region catchments, infiltration through the streambed occurs at rates dependent on factors such as antecedent conditions, flow rate, flow duration, channel morphology, and sediment texture and composition. The study provides an important reference for sustainable management of alluvial aquifer systems in similar regions.

  10. Comparing the impacts of mature spruce forests and grasslands on snow melt, water resource recharge, and run-off in the northern boreal environment

    Directory of Open Access Journals (Sweden)

    Jiří Kremsa


    Full Text Available Snow-melt runoff is an important factor in control of flooding and soil erosion in higher and cold regions of the world. In 1992–2008–2008, processes of snow accumulation and melting were monitored at two adjacent sites of the Paljakka environmental research centre (Finland. The forest stand of mature spruce (Picea abies has been compared with adjacent, local, and open grassland. In the forest, snowpack duration fluctuated for 180–245 days, with a maximum depth of 78–152 cm and snow–water content of 167–406 mm, while in the open grassland this occurred for some 20 days less, with maximum depth 65–122 cm, and snow–water content 143–288 mm. The snow–water captured in the canopy reached a maximum 27% of that registered on the ground; the loss of intercepted snow by sublimation was approximately 26% of the annual snowfall. During the high melt period (April–May, the degree-day factor in the forest stand achieved 60% of values observed in the grassland (2.3–3.5 against 3.8–6.0 mm °C−1 day−1. The hydrological model BROOK 90 was employed to analyse potential water resources recharge, and flood risk at Paljakka. Considering the normal climate season, snow-melt runoff from the forest exceeded the grassland by 22% (225 against 185 mm. In extreme situations, the maximum daily runoff from snow-melt in the grasslands (57 mm day−1 exceeded 2.6 times the values in spruce forest (22 mm day−1.

  11. Climate variability and vadose zone controls on damping of transient recharge (United States)

    Corona, Claudia R.; Gurdak, Jason J.; Dickinson, Jesse; Ferré, T.P.A.; Maurer, Edwin P.


    Increasing demand on groundwater resources motivates understanding of the controls on recharge dynamics so model predictions under current and future climate may improve. Here we address questions about the nonlinear behavior of flux variability in the vadose zone that may explain previously reported teleconnections between global-scale climate variability and fluctuations in groundwater levels. We use hundreds of HYDRUS-1D simulations in a sensitivity analysis approach to evaluate the damping depth of transient recharge over a range of periodic boundary conditions and vadose zone geometries and hydraulic parameters that are representative of aquifer systems of the conterminous United States (U.S). Although the models were parameterized based on U.S. aquifers, findings from this study are applicable elsewhere that have mean recharge rates between 3.65 and 730 mm yr–1. We find that mean infiltration flux, period of time varying infiltration, and hydraulic conductivity are statistically significant predictors of damping depth. The resulting framework explains why some periodic infiltration fluxes associated with climate variability dampen with depth in the vadose zone, resulting in steady-state recharge, while other periodic surface fluxes do not dampen with depth, resulting in transient recharge. We find that transient recharge in response to the climate variability patterns could be detected at the depths of water levels in most U.S. aquifers. Our findings indicate that the damping behavior of transient infiltration fluxes is linear across soil layers for a range of texture combinations. The implications are that relatively simple, homogeneous models of the vadose zone may provide reasonable estimates of the damping depth of climate-varying transient recharge in some complex, layered vadose zone profiles.

  12. Input Digital Datasets for the Soil-Water Balance Groundwater Recharge Model of the Upper Colorado River Basin (United States)

    U.S. Geological Survey, Department of the Interior — The Colorado River and its tributaries supply water to more than 35 million people in the United States and 3 million people in Mexico, irrigating more than 4.5...

  13. Biofouling potential and material reactivity in a simulated water distribution network supplied with stormwater recycled via managed aquifer recharge. (United States)

    Gonzalez, Dennis; Tjandraatmadja, Grace; Barry, Karen; Vanderzalm, Joanne; Kaksonen, Anna H; Dillon, Peter; Puzon, Geoff J; Sidhu, Jatinder; Wylie, Jason; Goodman, Nigel; Low, Jason


    The injection of stormwater into aquifers for storage and recovery during high water demand periods is a promising technology for augmenting conventional water reserves. Limited information exists regarding the potential impact of aquifer treated stormwater in distribution system infrastructure. This study describes a one year pilot distribution pipe network trial to determine the biofouling potential for cement, copper and polyvinyl chloride pipe materials exposed to stormwater stored in a limestone aquifer compared to an identical drinking water rig. Median alkalinity (123 mg/L) and colour (12 HU) in stormwater was significantly higher than in drinking water (82 mg/L and 1 HU) and pipe discolouration was more evident for stormwater samples. X-ray Diffraction and Fluorescence analyses confirmed this was driven by the presence of iron rich amorphous compounds in more thickly deposited sediments also consistent with significantly higher median levels of iron (∼0.56 mg/L) in stormwater compared to drinking water (∼0.17 mg/L). Water type did not influence biofilm development as determined by microbial density but faecal indicators were significantly higher for polyvinyl chloride and cement exposed to stormwater. Treatment to remove iron through aeration and filtration would reduce the potential for sediment accumulation. Operational and verification monitoring parameters to manage scaling, corrosion, colour, turbidity and microbial growth in recycled stormwater distribution networks are discussed.

  14. Water-Isotopes (2H, 3H, 18O) to trace the source and timing of recharge in a fractured granite aquifer in Western Kenya, Africa (United States)

    Kralik, Martin; Whylidal, Stefan; Asunah, Francis; Sültenfuß, Jürgen


    seasons are significantly lower (-3 to -4 o) than in the mean precipitation during the rest of the year (-2.5 to -1.9 o; Mwango, 2003) one can conclude that the main spring 'Anzaya' and the well in the Naboka Secondary School are recharged from deeper faults with water supplied more during the rainy season. The slightly higher d-excess of 13.4-14.2 ocompared to 11.7-12.6 oin the rest of the samples, indicates a somewhat higher recharge area of this two sites with water vapor recycled in the precipitation around the Liailhunuu peak (ca. 1675m). This effect is also supported by spring-water measurements at the Kilimanjaro (d-excess 13.4-6.6 o) 400 km SE. Similarily, the tritium content of 1.42 - 1.62 TU indicate that compared to a mean tritium content of 2 TU in the rain of this area (Mwango, 2003) the mean residence time can be in the range of recent to few years only.

  15. An ontology design pattern for surface water features (United States)

    Sinha, Gaurav; Mark, David; Kolas, Dave; Varanka, Dalia; Romero, Boleslo E.; Feng, Chen-Chieh; Usery, E. Lynn; Liebermann, Joshua; Sorokine, Alexandre


    Surface water is a primary concept of human experience but concepts are captured in cultures and languages in many different ways. Still, many commonalities exist due to the physical basis of many of the properties and categories. An abstract ontology of surface water features based only on those physical properties of landscape features has the best potential for serving as a foundational domain ontology for other more context-dependent ontologies. The Surface Water ontology design pattern was developed both for domain knowledge distillation and to serve as a conceptual building-block for more complex or specialized surface water ontologies. A fundamental distinction is made in this ontology between landscape features that act as containers (e.g., stream channels, basins) and the bodies of water (e.g., rivers, lakes) that occupy those containers. Concave (container) landforms semantics are specified in a Dry module and the semantics of contained bodies of water in a Wet module. The pattern is implemented in OWL, but Description Logic axioms and a detailed explanation is provided in this paper. The OWL ontology will be an important contribution to Semantic Web vocabulary for annotating surface water feature datasets. Also provided is a discussion of why there is a need to complement the pattern with other ontologies, especially the previously developed Surface Network pattern. Finally, the practical value of the pattern in semantic querying of surface water datasets is illustrated through an annotated geospatial dataset and sample queries using the classes of the Surface Water pattern.

  16. Water use patterns and conservation in households of Wei River Basin, China

    NARCIS (Netherlands)

    Fan, L.; Liu, G.; Wang, F.; Geissen, V.; Ritsema, C.J.


    Fully understanding patterns of water use and water conservation among different consumer groups will help in implementing more effective water conservation programs worldwide. Consequently, we investigated water use patterns, water conservation practices, attitudes, and hindrances to water conserva

  17. 咸阳地压地热流体补给的环境同位素证据%Environmental isotope evidences of recharge of geopressured geothermal waters in Xianyang

    Institute of Scientific and Technical Information of China (English)

    李婷; 胡伟伟; 马致远; 豆惠萍


    By systematically illustrating the recharge source, direction and period of geopressured geothermal waters in Xianyang by studying environmental isotope, the result shows that the main recharge source originates from mospheric water pre-Holocene Epoch, which is from the west and northwest of study area. Its updating ablility is poor except partial deep fault slightly recharge from modern mospheric water.%通过对咸阳地压地热流体的环境同位素研究,系统论证了咸阳地压地热流体的补给来源、补给方向及补给年代。研究表明:咸阳地压地热流体的补给来源主要为全新世前古大气降水,其补给方向主要来自研究区西部及西北部,除局部深大断裂附近有少量现代降水补给外,其可更新能力较差。

  18. Spatial and temporal infiltration dynamics during managed aquifer recharge. (United States)

    Racz, Andrew J; Fisher, Andrew T; Schmidt, Calla M; Lockwood, Brian S; Los Huertos, Marc


    Natural groundwater recharge is inherently difficult to quantify and predict, largely because it comprises a series of processes that are spatially distributed and temporally variable. Infiltration ponds used for managed aquifer recharge (MAR) provide an opportunity to quantify recharge processes across multiple scales under semi-controlled conditions. We instrumented a 3-ha MAR infiltration pond to measure and compare infiltration patterns determined using whole-pond and point-specific methods. Whole-pond infiltration was determined by closing a transient water budget (accounting for inputs, outputs, and changes in storage), whereas point-specific infiltration rates were determined using heat as a tracer and time series analysis at eight locations in the base of the pond. Whole-pond infiltration, normalized for wetted area, rose rapidly to more than 1.0 m/d at the start of MAR operations (increasing as pond stage rose), was sustained at high rates for the next 40 d, and then decreased to less than 0.1 m/d by the end of the recharge season. Point-specific infiltration rates indicated high spatial and temporal variability, with the mean of measured values generally being lower than rates indicated by whole-pond calculations. Colocated measurements of head gradients within saturated soils below the pond were combined with infiltration rates to calculate soil hydraulic conductivity. Observations indicate a brief period of increasing saturated hydraulic conductivity, followed by a decrease of one to two orders of magnitude during the next 50 to 75 d. Locations indicating the most rapid infiltration shifted laterally during MAR operation, and we suggest that infiltration may function as a "variable source area" processes, conceptually similar to catchment runoff.

  19. An approach to identify urban groundwater recharge

    Directory of Open Access Journals (Sweden)

    E. Vázquez-Suñé


    Full Text Available Evaluating the proportion in which waters from different origins are mixed in a given water sample is relevant for many hydrogeological problems, such as quantifying total recharge, assessing groundwater pollution risks, or managing water resources. Our work is motivated by urban hydrogeology, where waters with different chemical signature can be identified (losses from water supply and sewage networks, infiltration from surface runoff and other water bodies, lateral aquifers inflows, .... The relative contribution of different sources to total recharge can be quantified by means of solute mass balances, but application is hindered by the large number of potential origins. Hence, the need to incorporate data from a large number of conservative species, the uncertainty in sources concentrations and measurement errors. We present a methodology to compute mixing ratios and end-members composition, which consists of (i Identification of potential recharge sources, (ii Selection of tracers, (iii Characterization of the hydrochemical composition of potential recharge sources and mixed water samples, and (iv Computation of mixing ratios and reevaluation of end-members. The analysis performed in a data set from samples of the Barcelona city aquifers suggests that the main contributors to total recharge are the water supply network losses (22%, the sewage network losses (30%, rainfall, concentrated in the non-urbanized areas (17%, from runoff infiltration (20%, and the Besòs River (11%. Regarding species, halogens (chloride, fluoride and bromide, sulfate, total nitrogen, and stable isotopes (18O, 2H, and 34S behaved quite conservatively. Boron, residual alkalinity, EDTA and Zn did not. Yet, including these species in the computations did not affect significantly the proportion estimations.

  20. An approach to identify urban groundwater recharge

    Directory of Open Access Journals (Sweden)

    E. Vázquez-Suñé


    Full Text Available Evaluating the proportion in which waters from different origins are mixed in a given water sample is relevant for many hydrogeological problems, such as quantifying total recharge, assessing groundwater pollution risks, or managing water resources. Our work is motivated by urban hydrogeology, where waters with different chemical signature can be identified (losses from water supply and sewage networks, infiltration from surface runoff and other water bodies, lateral aquifers inflows, .... The relative contribution of different sources to total recharge can be quantified by means of solute mass balances, but application is hindered by the large number of potential origins. Hence, the need to incorporate data from a large number of conservative species, the uncertainty in sources concentrations and measurement errors. We present a methodology to compute mixing ratios and end-members composition, which consists of (i Identification of potential recharge sources, (ii Selection of tracers, (iii Characterization of the hydrochemical composition of potential recharge sources and mixed water samples, and (iv Computation of mixing ratios and reevaluation of end-members. The analysis performed in a data set from samples of the Barcelona city aquifers suggests that the main contributors to total recharge are the water supply network losses (22%, the sewage network losses (30%, rainfall, concentrated in the non-urbanized areas (17%, from runoff infiltration (20%, and the Besòs River (11%. Regarding species, halogens (chloride, fluoride and bromide, sulfate, total nitrogen, and stable isotopes (18O2H, and 34S behaved quite conservatively. Boron, residual alkalinity, EDTA and Zn did not. Yet, including these species in the computations did not affect significantly the proportion estimations.

  1. Global-scale modeling of groundwater recharge (United States)

    Döll, P.; Fiedler, K.


    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


    Energy Technology Data Exchange (ETDEWEB)

    Lutz, Jim; Melody, Moya


    There is significant variation in hot water use and draw patterns among households. This report describes typical hot water use patterns in single-family residences in North America. We found that daily hot water use is highly variable both among residences and within the same residence. We compared the results of our analysis of the field data to the conditions and draw patterns established in the current U.S. Department of Energy (DOE) test procedure for residential water heaters. The results show a higher number of smaller draws at lower flow rates than used in the test procedure. The data from which the draw patterns were developed were obtained from 12 separate field studies. This report describes the ways in which we managed, cleaned, and analyzed the data and the results of our data analysis. After preparing the data, we used the complete data set to analyze inlet and outlet water temperatures. Then we divided the data into three clusters reflecting house configurations that demonstrated small, medium, or large median daily hot water use. We developed the three clusters partly to reflect efforts of the ASHRAE standard project committee (SPC) 118.2 to revise the test procedure for residential water heaters to incorporate a range of draw patterns. ASHRAE SPC 118.2 has identified the need to separately evaluate at least three, and perhaps as many as five, different water heater capacities. We analyzed the daily hot water use data within each cluster in terms of volume and number of hot water draws. The daily draw patterns in each cluster were characterized using distributions for volume of draws, duration of draws, time since previous draw, and flow rates.

  3. Stable H and O isotope variations reveal sources of recharge in Dhofar, Sultanate of Oman. (United States)

    Strauch, Gerhard; Al-Mashaikhi, Khalid S; Bawain, Abdullah; Knöller, Kay; Friesen, Jan; Müller, Thomas


    Due to the ability of stable water isotopes to characterize the origin of water and connected processes of groundwater recharge, we used the isotope variations of hydrogen and oxygen in different water sources for assessing the recharge process in the Dhofar region. δ(18)O and δ(2)H of precipitation, spring water, and groundwater cover a range from -10 to +2 and from -70 to +7 ‰ (vs Vienna Standard Mean Ocean Water), respectively, and correlate in a linear relationship close to the Global Meteoric Water Line. No obvious evaporation processes are detected. A clear signal of the recent precipitation is given by the annual monsoon. The monsoon signal is confirmed by several springs existing in the south at the foot of the Dhofar mountains and sources at Gogub above 450 m and Tawi Atir at 650 m above sea level. They occur here first in the form of water intercepted by trees as stemflow and throughflow. The isotope signature of groundwater in the Dhofar mountains reflects the climatic conditions at the time of recharge and the lithological features of the limestone matrix. To the north, the isotope patterns of the groundwater are continuously depleted from the monsoon signal along the outcropping aquifer D (Lower Umm Er Radhuma). Here, a more negative signature towards the wells in the Najd desert region was observed. Cyclone water that flooded wadis in the Dhofar region occasionally, as observed in November 2011, falls isotopically into the same range as we observed in the fossil groundwater. Taking into account the different sources of precipitation and groundwater and thus a clear distinction of the isotopic composition of the water sources, we conclude a recharge process divided into a southward and a northward component in the Dhofar region.

  4. Wireless rechargeable sensor networks

    CERN Document Server

    Yang, Yuanyuan


    This SpringerBrief provides a concise guide to applying wireless energy transfer techniques in traditional battery-powered sensor networks. It examines the benefits and challenges of wireless power including efficiency and reliability. The authors build a wireless rechargeable sensor networks from scratch and aim to provide perpetual network operation. Chapters cover a wide range of topics from the collection of energy information and recharge scheduling to joint design with typical sensing applications such as data gathering. Problems are approached using a natural combination of probability

  5. Soil moisture data as a constraint for groundwater recharge estimation (United States)

    Mathias, Simon A.; Sorensen, James P. R.; Butler, Adrian P.


    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.

  6. Raw Water Quality and Pretreatment in Managed  Aquifer Recharge for Drinking Water Production in Finland

    Directory of Open Access Journals (Sweden)

    Petri Jokela


    Full Text Available The main objective of managed aquifer recharge (MAR in Finland is the removal of natural organic matter (NOM from surface waters. A typical MAR procedure consists of the infiltration of surface water into a Quaternary glaciofluvial esker with subsequent withdrawal of the MAR treated water from wells a few hundred meters downstream. The infiltrated water should have a residence time of at least approximately one month before withdrawal to provide sufficient time for the subsurface processes needed to break down or remove humic substances. Most of the Finnish MAR plants do not have pretreatment and raw water is infiltrated directly into the soil. The objectives of this paper are to present MAR experiences and to discuss the need for and choice of pretreatment. Data from basin, sprinkling, and well infiltration processes are presented. Total organic carbon (TOC concentrations of the raw waters presented here varied from 6.5 to 11 mg/L and after MAR the TOC concentrations of the abstracted waters were approximately 2 mg/L. The overall reduction of organic matter in the treatment (with or without pretreatment was 70%-85%. Mechanical pretreatment can be used for clogging prevention. Turbidity of the Finnish lakes used as raw water does not necessitate pretreatment in basin and sprinkling infiltration, however, pretreatment in well infiltration needs to be judged separately. River waters may have high turbidity requiring pretreatment. Biodegradation of NOM in the saturated groundwater zone consumes dissolved oxygen. Thus, a high NOM concentration may create conditions for dissolution of iron and manganese from the soil. These conditions may be avoided by the addition of chemical pretreatment. Raw waters with TOC content up to at least approximately 8 mg/L were infiltrated without any considerations of chemical pretreatment, which should be evaluated based on local conditions.

  7. Quantifying Potential Groundwater Recharge In South Texas (United States)

    Basant, S.; Zhou, Y.; Leite, P. A.; Wilcox, B. P.


    Groundwater in South Texas is heavily relied on for human consumption and irrigation for food crops. Like most of the south west US, woody encroachment has altered the grassland ecosystems here too. While brush removal has been widely implemented in Texas with the objective of increasing groundwater recharge, the linkage between vegetation and groundwater recharge in South Texas is still unclear. Studies have been conducted to understand plant-root-water dynamics at the scale of plants. However, little work has been done to quantify the changes in soil water and deep percolation at the landscape scale. Modeling water flow through soil profiles can provide an estimate of the total water flowing into deep percolation. These models are especially powerful with parameterized and calibrated with long term soil water data. In this study we parameterize the HYDRUS soil water model using long term soil water data collected in Jim Wells County in South Texas. Soil water was measured at every 20 cm intervals up to a depth of 200 cm. The parameterized model will be used to simulate soil water dynamics under a variety of precipitation regimes ranging from well above normal to severe drought conditions. The results from the model will be compared with the changes in soil moisture profile observed in response to vegetation cover and treatments from a study in a similar. Comparative studies like this can be used to build new and strengthen existing hypotheses regarding deep percolation and the role of soil texture and vegetation in groundwater recharge.

  8. Rechargeable power supply

    NARCIS (Netherlands)

    Den Uijl, S.; Bouman, C.; Smit, W.


    The invention relates to a rechargeable power supply suitable to be used in a battery-operated device comprising at least one supercapacitor and at least a first and a second DC-DC converter connected in series, wherein the supercapacitor is connectable to an entry of the first DC-DC converter and t

  9. Drinking water consumption patterns in Canadian communities (2001-2007). (United States)

    Roche, S M; Jones, A Q; Majowicz, S E; McEwen, S A; Pintar, K D M


    A pooled analysis of seven cross-sectional studies from Newfoundland and Labrador, Waterloo and Hamilton Regions, Ontario and Vancouver, East Kootenay and Northern Interior Regions, British Columbia (2001 to 2007) was performed to investigate the drinking water consumption patterns of Canadians and to identify factors associated with the volume of tap water consumed. The mean volume of tap water consumed was 1.2 L/day, with a large range (0.03 to 9.0 L/day). In-home water treatment and interactions between age and gender and age and bottled water use were significantly associated with the volume of tap water consumed in multivariable analyses. Approximately 25% (2,221/8,916) of participants were classified as bottled water users, meaning that 75% or more of their total daily drinking water intake was bottled. Approximately 48.6% (4,307/8,799) of participants used an in-home treatment method to treat their tap water for drinking purposes. This study provides a broader geographic perspective and more current estimates of Canadian water consumption patterns than previous studies. The identified factors associated with daily water consumption could be beneficial for risk assessors to identify individuals who may be at greater risk of waterborne illness.

  10. Groundwater recharge from point to catchment scale (United States)

    Leterme, Bertrand; Di Ciacca, Antoine; Laloy, Eric; Jacques, Diederik


    Accurate estimation of groundwater recharge is a challenging task as only a few devices (if any) can measure it directly. In this study, we discuss how groundwater recharge can be calculated at different temporal and spatial scales in the Kleine Nete catchment (Belgium). A small monitoring network is being installed, that is aimed to monitor the changes in dominant processes and to address data availability as one goes from the point to the catchment scale. At the point scale, groundwater recharge is estimated using inversion of soil moisture and/or water potential data and stable isotope concentrations (Koeniger et al. 2015). At the plot scale, it is proposed to monitor the discharge of a small drainage ditch in order to calculate the field groundwater recharge. Electrical conductivity measurements are necessary to separate shallow from deeper groundwater contribution to the ditch discharge (see Di Ciacca et al. poster in session HS8.3.4). At this scale, two or three-dimensional process-based vadose zone models will be used to model subsurface flow. At the catchment scale though, using a mechanistic, process-based model to estimate groundwater recharge is debatable (because of, e.g., the presence of numerous drainage ditches, mixed land use pixels, etc.). We therefore investigate to which extent various types of surrogate models can be used to make the necessary upscaling from the plot scale to the scale of the whole Kleine Nete catchment. Ref. Koeniger P, Gaj M, Beyer M, Himmelsbach T (2015) Review on soil water isotope based groundwater recharge estimations. Hydrological Processes, DOI: 10.1002/hyp.10775

  11. Geochemical quantification of semiarid mountain recharge. (United States)

    Wahi, Arun K; Hogan, James F; Ekwurzel, Brenda; Baillie, Matthew N; Eastoe, Christopher J


    Analysis of a typical semiarid mountain system recharge (MSR) setting demonstrates that geochemical tracers help resolve the location, rate, and seasonality of recharge as well as ground water flowpaths and residence times. MSR is defined as the recharge at the mountain front that dominates many semiarid basins plus the often-overlooked recharge through the mountain block that may be a significant ground water resource; thus, geochemical measurements that integrate signals from all flowpaths are advantageous. Ground water fluxes determined from carbon-14 ((14)C) age gradients imply MSR rates between 2 x 10(6) and 9 x 10(6) m(3)/year in the Upper San Pedro Basin, Arizona, USA. This estimated range is within an order of magnitude of, but lower than, prior independent estimates. Stable isotopic signatures indicate that MSR has a 65% +/- 25% contribution from winter precipitation and a 35% +/- 25% contribution from summer precipitation. Chloride and stable isotope results confirm that transpiration is the dominant component of evapotranspiration (ET) in the basin with typical loss of more than 90% of precipitation-less runoff to ET. Such geochemical constraints can be used to further refine hydrogeologic models in similar high-elevation relief basins and can provide practical first estimates of MSR rates for basins lacking extensive prior hydrogeologic measurements.

  12. Climate variability effects on urban recharge beneath low impact development (United States)

    Newcomer, M. E.; Gurdak, J. J.


    Groundwater resources in urban and coastal environments are highly vulnerable to human pressures and climate variability and change, and many communities face water shortages and need to find alternative water supplies. Therefore, understanding how low impact development (LID) site planning and integrated/best management practices (BMPs) affect recharge rates and volumes is important because of the increasing use of LID and BMP to reduce stormwater runoff and improve surface-water quality. Often considered a secondary management benefit, many BMPs may also enhance recharge to local aquifers; however these hypothesized benefits have not been thoroughly tested or quantified. In this study, we quantify stormwater capture and recharge enhancement beneath a BMP infiltration trench of the LID research network at San Francisco State University, San Francisco, California. Stormwater capture and retention was analyzed using the SCS TR-55 curve number method and in-situ infiltration rates to assess LID storage. Recharge was quantified using vadose zone monitoring equipment, a detailed water budget analysis, and a Hydrus-2D model. Additionally, the effects of historical and predicted future precipitation on recharge rates were examined using precipitation from the Geophysical Fluid Dynamic Laboratory (GFDL) A1F1 climate scenario. Observed recharge rates beneath the infiltration trench range from 1,600 to 3,700 mm/year and are an order of magnitude greater than recharge beneath an irrigated grass lawn and a natural setting. The Hydrus-2D model results indicate increased recharge under the GFDL A1F1 scenario compared with historical and GFDL modeled 20th century rates because of the higher frequency of large precipitation events that induce runoff into the infiltration trench. However, under a simulated A1F1 El Niño year, recharge calculated by a water budget does not increase compared with current El Niño recharge rates. In comparison, simulated recharge rates were

  13. Environmental Isotope Evidence of Geothermal Water Recharge in Xi’an Southern Sag%西安凹陷中南部地下热水补给的环境同位素证据

    Institute of Scientific and Technical Information of China (English)

    张雪莲; 马致远; 徐国芳


    The supply of Xi’ an depression southern abdominal deep and shallow under-ground hot water was studied with environment isotope method ,the results showed that Xi’an depression abdominal shallow geothermal water points were mainly distributed near the line of atmospheric precipitation ,only two points had diverged ,meaning that they were accepted from modern precipitation and ancient precipitationin the north of Qinling Mountains ,while the deep geothermal water with the tritium content was less than 1 TU and the average value of 14C dating was more than twenty thousand ,meaning that it was ac-cepted from ancient precipitation recharge before Holocene in the north of Qinling Mountains .The result showed that the deep and shallow underground hot water inflowed from the southwest direction .The range of the recharge height was 839 m-1 746 m .The annual average temperature was 0 .69 ℃ when the deep and shallow underground hot water received recharge .The recharge environment was the pore and fracture type underground hot water system .%应用环境同位素方法对西安凹陷中南部深层和浅层地下热水补给进行研究,结果显示,西安凹陷中南部浅层地热水样点主要分布在大气降水线附近,个别点发生δ18 O漂移,表明其接受来自秦岭北麓现代降水和古降水的混合补给,深层地热水氚含量小于1 TU ,14C测年平均在两万年以上,表明其接受秦岭北麓全新世前古降水补给;深、浅层地下热水接受补给的方向为西南方向,补给高程为839~1746 m ;深层(热水埋深为1000~4000 m )、浅层(热水埋深小于1000 m )地下热水接受补给时的年平均温度为0.69℃,补给环境为孔隙裂隙型地下热水系统。

  14. An Ontology Design Pattern for Surface Water Features

    Energy Technology Data Exchange (ETDEWEB)

    Sinha, Gaurav [Ohio University; Mark, David [University at Buffalo (SUNY); Kolas, Dave [Raytheon BBN Technologies; Varanka, Dalia [U.S. Geological Survey, Rolla, MO; Romero, Boleslo E [University of California, Santa Barbara; Feng, Chen-Chieh [National University of Singapore; Usery, Lynn [U.S. Geological Survey, Rolla, MO; Liebermann, Joshua [Tumbling Walls, LLC; Sorokine, Alexandre [ORNL


    Surface water is a primary concept of human experience but concepts are captured in cultures and languages in many different ways. Still, many commonalities can be found due to the physical basis of many of the properties and categories. An abstract ontology of surface water features based only on those physical properties of landscape features has the best potential for serving as a foundational domain ontology. It can then be used to systematically incor-porate concepts that are specific to a culture, language, or scientific domain. The Surface Water ontology design pattern was developed both for domain knowledge distillation and to serve as a conceptual building-block for more complex surface water ontologies. A fundamental distinction is made in this on-tology between landscape features that act as containers (e.g., stream channels, basins) and the bodies of water (e.g., rivers, lakes) that occupy those containers. Concave (container) landforms semantics are specified in a Dry module and the semantics of contained bodies of water in a Wet module. The pattern is imple-mented in OWL, but Description Logic axioms and a detailed explanation is provided. The OWL ontology will be an important contribution to Semantic Web vocabulary for annotating surface water feature datasets. A discussion about why there is a need to complement the pattern with other ontologies, es-pecially the previously developed Surface Network pattern is also provided. Fi-nally, the practical value of the pattern in semantic querying of surface water datasets is illustrated through a few queries and annotated geospatial datasets.

  15. Vegetation pattern formation of a water-biomass model (United States)

    Wang, Xiaoli; Wang, Wendi; Zhang, Guohong


    In this paper, a mathematical model with diffusion and cross-diffusion is proposed to describe the interaction between the vegetation and the soil water. Based on the view of Turing pattern, we discuss the conditions of the diffusion-induced instability and the cross-diffusion-induced instability of a homogenous uniform steady state. We find that either a fast diffusion speed of water or a great hydraulic diffusivity due to the suction of roots may drive the instability of the homogenous steady state. Furthermore, we find that both the rain-fall rate and the infiltration feedback parameter can induce the transitions among the vegetation state, pattern formation and bare soil state. It is also found that the "terrain slope" may cause the instability of the homogenous steady state and drive the formation of periodic stripe pattern. Consequently, the diversity of dryland vegetation in reality can be explained as a result of pattern solutions of the model.


    Directory of Open Access Journals (Sweden)

    Ionut Minea


    Full Text Available ABSTRACT. – Patterns utilized in the simulation of underground water flow and the transportation of pollutants in the Bahlui drainage basin. In the actual context of accelerate economic development, the excessive exploatation of water resources from the underground and the contamination of these with different water pollutants has become a major problem which has enetered the attention of many researchers. For the evaluation of an underground water flow and pollutants transport sistem we have chosen the package of programs MODFLOW which includes a whole series of applications,such as MOC3D, MT3D, MT3DMS, PEST, UCODE, PMPATH, which allow simulations and multiple recalibrations of the capacity of recharging of the aquifers, the flowing of the water towards wells and drillings the transport of a pollutant agent in the underground or the evaluation of the exchange of water between the hidrographic network and aquifers. The sistem targets both the evaluation of the modelation of the underground flowing and the simulation of a punctual polluation of the canvas of groundwater scenery, in the meadow of the river Bahlui, west from Letcani village.

  17. Estimation of groundwater recharge in arid and semi-arid areas based on water cycle simulation%基于水循环模拟的干旱半干旱地区地下水补给评价

    Institute of Scientific and Technical Information of China (English)

    陆垂裕; 孙青言; 李慧; 盖燕如


    干旱半干旱地区的地下水补给评价在地下水的开发利用和保护中起着基础性的重要作用。本文从全区域水循环整体的角度出发,以水循环模拟与地下水数值模拟紧密耦合的综合性水文模型 MODCYCLE为工具,以处于半干旱地区的通辽市平原区为例,探索地下水在“自然-社会”二元水循环过程中的补给规律。结果表明:通辽市平原区地下水的主要补给来源为降水入渗,占总补给量的65.2%;降水入渗补给量与降水量的变化趋势基本一致,但受众多因素影响,并不呈线性关系;年均降水入渗补给量农田区107.3 mm,非农田生态区29.1 mm,且前者较后者稳定;地下水从人口分布较少的平原坨沼区向社会经济活动频繁的中部平原区侧向净流动,年均净流量为6570万m3,呈逐年下降趋势。模型反映的地下水补给规律基本符合研究区域的客观情况,可以为当地地下水管理提供参考。该评价方法为类似地区的地下水研究提供一种可以选择的方式。%Groundwater recharge evaluation in arid and semi-arid areas plays a foundational role in the ex⁃ploitation and protection of the groundwater. In this study, from the perspective of water cycle for the whole region, the law of groundwater recharge is explored in the artificial-natural dual water cycle. The in⁃tegrated hydrology model named MODCYCLE is used, which is formed by the tightly-coupling of the water cycle model and the groundwater numerical simulation. The groundwater of the plain area in Tongliao, a typical semi-arid region, is evaluated as an example. The analytical results show that (1) the precipitation recharge, 65.2 % of the total recharge, is the main supply source of groundwater;(2) the variation trends of precipitation recharge and precipitation are basically consistent, but influenced by many factors, not a linear relationship;(3) the average annual amount of

  18. Global synthesis of groundwater recharge in semiarid and arid regions (United States)

    Scanlon, Bridget R.; Keese, Kelley E.; Flint, Alan L.; Flint, Lorraine E.; Gaye, Cheikh B.; Edmunds, W. Michael; Simmers, Ian


    Global synthesis of the findings from 140 recharge study areas in semiarid and arid regions provides important information on recharge rates, controls, and processes, which are critical for sustainable water development. Water resource evaluation, dryland salinity assessment (Australia), and radioactive waste disposal (US) are among the primary goals of many of these recharge studies. The chloride mass balance (CMB) technique is widely used to estimate recharge. Average recharge rates estimated over large areas (40-374 000 km2) range from 0.2 to 35 mm year-1, representing 0.1-5% of long-term average annual precipitation. Extreme local variability in recharge, with rates up to 720 m year-1, results from focussed recharge beneath ephemeral streams and lakes and preferential flow mostly in fractured systems. System response to climate variability and land use/land cover (LU/LC) changes is archived in unsaturated zone tracer profiles and in groundwater level fluctuations. Inter-annual climate variability related to El Niño Southern Oscillation (ENSO) results in up to three times higher recharge in regions within the SW US during periods of frequent El Niños (1977-1998) relative to periods dominated by La Niñas (1941-1957). Enhanced recharge related to ENSO is also documented in Argentina. Climate variability at decadal to century scales recorded in chloride profiles in Africa results in recharge rates of 30 mm year-1 during the Sahel drought (1970-1986) to 150 mm year-1 during non-drought periods. Variations in climate at millennial scales in the SW US changed systems from recharge during the Pleistocene glacial period (10 000 years ago) to discharge during the Holocene semiarid period. LU/LC changes such as deforestation in Australia increased recharge up to about 2 orders of magnitude. Changes from natural grassland and shrublands to dryland (rain-fed) agriculture altered systems from discharge (evapotranspiration, ET) to recharge in the SW US. The impact of LU

  19. Global synthesis of groundwater recharge in semiarid and arid regions (United States)

    Scanlon, B.R.; Keese, K.E.; Flint, A.L.; Flint, L.E.; Gaye, C.B.; Edmunds, W.M.; Simmers, I.


    Global synthesis of the findings from ???140 recharge study areas in semiarid and arid regions provides important information on recharge rates, controls, and processes, which are critical for sustainable water development. Water resource evaluation, dryland salinity assessment (Australia), and radioactive waste disposal (US) are among the primary goals of many of these recharge studies. The chloride mass balance (CMB) technique is widely used to estimate recharge. Average recharge rates estimated over large areas (40-374000 km2) range from 0.2 to 35 mm year-1, representing 0.1-5% of long-term average annual precipitation. Extreme local variability in recharge, with rates up to ???720 m year-1, results from focussed recharge beneath ephemeral streams and lakes and preferential flow mostly in fractured systems. System response to climate variability and land use/land cover (LU/LC) changes is archived in unsaturated zone tracer profiles and in groundwater level fluctuations. Inter-annual climate variability related to El Nin??o Southern Oscillation (ENSO) results in up to three times higher recharge in regions within the SW US during periods of frequent El Nin??os (1977-1998) relative to periods dominated by La Nin??as (1941-1957). Enhanced recharge related to ENSO is also documented in Argentina. Climate variability at decadal to century scales recorded in chloride profiles in Africa results in recharge rates of 30 mm year-1 during the Sahel drought (1970-1986) to 150 mm year-1 during non-drought periods. Variations in climate at millennial scales in the SW US changed systems from recharge during the Pleistocene glacial period (??? 10 000 years ago) to discharge during the Holocene semiarid period. LU/LC changes such as deforestation in Australia increased recharge up to about 2 orders of magnitude. Changes from natural grassland and shrublands to dryland (rain-fed) agriculture altered systems from discharge (evapotranspiration, ET) to recharge in the SW US. The

  20. Pattern Recognition for Reliability Assessment of Water Distribution Networks

    NARCIS (Netherlands)

    Trifunović, N.


    The study presented in this manuscript investigates the patterns that describe reliability of water distribution networks focusing to the node connectivity, energy balance, and economics of construction, operation and maintenance. A number of measures to evaluate the network resilience has been deve

  1. Determination of groundwater recharge mechanism in the deep loessial unsaturated zone by environmental tracers. (United States)

    Li, Zhi; Chen, Xi; Liu, Wenzhao; Si, Bingcheng


    Studying the groundwater recharge mechanism in regions with thick unsaturated zone can greatly improve our understanding of hydrological processes since these regions have complex groundwater processes. This study attempted to discuss the groundwater recharge in a region covered by loess over 130m deep in China's Loess Plateau. The water stable isotope, tritium and chloride in precipitation, groundwater and soil water were determined and used as inputs of mass balance methods. The tracer technique is found to be applicable and effective this region with thick unsaturated zone. The groundwater originates from rapid precipitation infiltration through some fast flow paths. The total recharge is likely to be 107±55mmyr(-1) accounting for 19±10% of average annual precipitation, while the recharge from preferential flow accounts for 87±4% of the total recharge. The identified recharge mechanism has important implication to groundwater management and recharge modeling for regions covered by thick loess.

  2. Using atmospheric tracers to reduce uncertainty in groundwater recharge areas. (United States)

    Starn, J Jeffrey; Bagtzoglou, Amvrossios C; Robbins, Gary A


    A Monte Carlo-based approach to assess uncertainty in recharge areas shows that incorporation of atmospheric tracer observations (in this case, tritium concentration) and prior information on model parameters leads to more precise predictions of recharge areas. Variance-covariance matrices, from model calibration and calculation of sensitivities, were used to generate parameter sets that account for parameter correlation and uncertainty. Constraining parameter sets to those that met acceptance criteria, which included a standard error criterion, did not appear to bias model results. Although the addition of atmospheric tracer observations and prior information produced similar changes in the extent of predicted recharge areas, prior information had the effect of increasing probabilities within the recharge area to a greater extent than atmospheric tracer observations. Uncertainty in the recharge area propagates into predictions that directly affect water quality, such as land cover in the recharge area associated with a well and the residence time associated with the well. Assessments of well vulnerability that depend on these factors should include an assessment of model parameter uncertainty. A formal simulation of parameter uncertainty can be used to delineate probabilistic recharge areas, and the results can be expressed in ways that can be useful to water-resource managers. Although no one model is the correct model, the results of multiple models can be evaluated in terms of the decision being made and the probability of a given outcome from each model.

  3. Using noble gas tracers to constrain a groundwater flow model with recharge elevations: A novel approach for mountainous terrain (United States)

    Doyle, Jessica M.; Gleeson, Tom; Manning, Andrew H.; Mayer, K. Ulrich


    Environmental tracers provide information on groundwater age, recharge conditions, and flow processes which can be helpful for evaluating groundwater sustainability and vulnerability. Dissolved noble gas data have proven particularly useful in mountainous terrain because they can be used to determine recharge elevation. However, tracer-derived recharge elevations have not been utilized as calibration targets for numerical groundwater flow models. Herein, we constrain and calibrate a regional groundwater flow model with noble-gas-derived recharge elevations for the first time. Tritium and noble gas tracer results improved the site conceptual model by identifying a previously uncertain contribution of mountain block recharge from the Coast Mountains to an alluvial coastal aquifer in humid southwestern British Columbia. The revised conceptual model was integrated into a three-dimensional numerical groundwater flow model and calibrated to hydraulic head data in addition to recharge elevations estimated from noble gas recharge temperatures. Recharge elevations proved to be imperative for constraining hydraulic conductivity, recharge location, and bedrock geometry, and thus minimizing model nonuniqueness. Results indicate that 45% of recharge to the aquifer is mountain block recharge. A similar match between measured and modeled heads was achieved in a second numerical model that excludes the mountain block (no mountain block recharge), demonstrating that hydraulic head data alone are incapable of quantifying mountain block recharge. This result has significant implications for understanding and managing source water protection in recharge areas, potential effects of climate change, the overall water budget, and ultimately ensuring groundwater sustainability.

  4. Improved Recharge Estimation from Portable, Low-Cost Weather Stations. (United States)

    Holländer, Hartmut M; Wang, Zijian; Assefa, Kibreab A; Woodbury, Allan D


    Groundwater recharge estimation is a critical quantity for sustainable groundwater management. The feasibility and robustness of recharge estimation was evaluated using physical-based modeling procedures, and data from a low-cost weather station with remote sensor techniques in Southern Abbotsford, British Columbia, Canada. Recharge was determined using the Richards-based vadose zone hydrological model, HYDRUS-1D. The required meteorological data were recorded with a HOBO(TM) weather station for a short observation period (about 1 year) and an existing weather station (Abbotsford A) for long-term study purpose (27 years). Undisturbed soil cores were taken at two locations in the vicinity of the HOBO(TM) weather station. The derived soil hydraulic parameters were used to characterize the soil in the numerical model. Model performance was evaluated using observed soil moisture and soil temperature data obtained from subsurface remote sensors. A rigorous sensitivity analysis was used to test the robustness of the model. Recharge during the short observation period was estimated at 863 and 816 mm. The mean annual recharge was estimated at 848 and 859 mm/year based on a time series of 27 years. The relative ratio of annual recharge-precipitation varied from 43% to 69%. From a monthly recharge perspective, the majority (80%) of recharge due to precipitation occurred during the hydrologic winter period. The comparison of the recharge estimates with other studies indicates a good agreement. Furthermore, this method is able to predict transient recharge estimates, and can provide a reasonable tool for estimates on nutrient leaching that is often controlled by strong precipitation events and rapid infiltration of water and nitrate into the soil.

  5. Economics of Managed Aquifer Recharge

    Directory of Open Access Journals (Sweden)

    Robert G. Maliva


    Full Text Available Managed aquifer recharge (MAR technologies can provide a variety of water resources management benefits by increasing the volume of stored water and improving water quality through natural aquifer treatment processes. Implementation of MAR is often hampered by the absence of a clear economic case for the investment to construct and operate the systems. Economic feasibility can be evaluated using cost benefit analysis (CBA, with the challenge of monetizing benefits. The value of water stored or treated by MAR systems can be evaluated by direct and indirect measures of willingness to pay including market price, alternative cost, value marginal product, damage cost avoided, and contingent value methods. CBAs need to incorporate potential risks and uncertainties, such as failure to meet performance objectives. MAR projects involving high value uses, such as potable supply, tend to be economically feasible provided that local hydrogeologic conditions are favorable. They need to have low construction and operational costs for lesser value uses, such as some irrigation. Such systems should therefore be financed by project beneficiaries, but dichotomies may exist between beneficiaries and payers. Hence, MAR projects in developing countries may be economically viable, but external support is often required because of limited local financial resources.

  6. 时变补给条件下河渠间潜水的一维非稳定运动%Water Table Fluctuation Between Two Parallel Ditches Induced by Time-varying Recharge

    Institute of Scientific and Technical Information of China (English)

    夏强; 许模; 邓英尔; 李晓


    Taking account of exponentially and periodically time-varying recharge,water table fluctuation be-tween two parallel ditches was studied.The analytical solution was derived based on the first linearization method of Boussinesq equation,and Duhamel principle.This paper analyzed the characteristics of phreatic water move-ment by using three kinds of recharge rate functions including exponent-increase,exponent-decay,and sine func-tion.In the first case,water table rises monotonously with the increasing recharge rate;and watershed between the two ditches moves from the higher level side towards the other sides,but will never cross the middle line of the aquifer.In the exponent-decay case,water table goes up at the beginning,then falls after reaching a peak value;watershed firstly moves towards the middle of the aquifer,then turns back to the higher level side due to the decli-ning recharge rate.In the last case,water table periodically fluctuates corresponding to the sine function recharge;and there is a significant time lag between the stimulator and the respond;watershed sways back and forth between the higher level ditch and the middle of the aquifer.The results can be a clue to study the response of groundwater system to climate change,in addition to the transition rule between surface and ground water.%针对河渠间潜水的一维非稳定运动,考虑了补给强度的时变性,根据Boussinesq方程的第一线性化方法,应用Duhamel原理得到了方程的解析解,进一步得出补给强度为指数函数和三角函数的潜水位计算公式。通过算例分析补给强度指数增加、指数衰减和正弦函数变化条件下潜水面的变化特征,指数增加条件下潜水位单调增加,分水岭从高水位一侧向河间地块中部移动;指数衰减条件下潜水位先增大,后减小,具有一个峰值,分水岭先从高水位一侧向河间地块中部移动,之后随补给强度减弱返回到高水位河渠;

  7. Water Use Patterns in Vietnamese Hotels: Modeling Toilet and Shower Usage

    National Research Council Canada - National Science Library

    Kanako Toyosada; Takayuki Otani; Yasutoshi Shimizu


    .... This study investigated water-use patterns in a hotel in Ho Chi Minh City in Vietnam. It aimed to quantify the efficiency of water-saving devices through modeling toilet and shower usage patterns, including water consumption...

  8. Impact of Large-scale Geological Architectures On Recharge (United States)

    Troldborg, L.; Refsgaard, J. C.; Engesgaard, P.; Jensen, K. H.

    Geological and hydrogeological data constitutes the basis for assessment of ground- water flow pattern and recharge zones. The accessibility and applicability of hard ge- ological data is often a major obstacle in deriving plausible conceptual models. Nev- ertheless focus is often on parameter uncertainty caused by the effect of geological heterogeneity due to lack of hard geological data, thus neglecting the possibility of alternative conceptualizations of the large-scale geological architecture. For a catchment in the eastern part of Denmark we have constructed different geologi- cal models based on different conceptualization of the major geological trends and fa- cies architecture. The geological models are equally plausible in a conceptually sense and they are all calibrated to well head and river flow measurements. Comparison of differences in recharge zones and subsequently well protection zones emphasize the importance of assessing large-scale geological architecture in hydrological modeling on regional scale in a non-deterministic way. Geostatistical modeling carried out in a transitional probability framework shows the possibility of assessing multiple re- alizations of large-scale geological architecture from a combination of soft and hard geological information.

  9. Modeling patterns of hot water use in households

    Energy Technology Data Exchange (ETDEWEB)

    Lutz, J.D.; Liu, Xiaomin; McMahon, J.E. [and others


    This report presents a detailed model of hot water use patterns in individual household. The model improves upon an existing model by including the effects of four conditions that were previously unaccounted for: the absence of a clothes washer; the absence of a dishwasher; a household consisting of seniors only; and a household that does not pay for its own hot water use. Although these four conditions can significantly affect residential hot water use, and have been noted in other studies, this is the first time that they have been incorporated into a detailed model. This model allows detailed evaluation of the impact of potential efficiency standards for water heaters and other market transformation policies. 21 refs., 3 figs., 10 tabs.

  10. Modeling patterns of hot water use in households

    Energy Technology Data Exchange (ETDEWEB)

    Lutz, James D.; Liu, Xiaomin; McMahon, James E.; Dunham, Camilla; Shown, Leslie J.; McCure, Quandra T.


    This report presents a detailed model of hot water use patterns in individual households. The model improves upon an existing model by including the effects of four conditions that were previously unaccounted for: the absence of a clothes washer; the absence of a dishwasher; a household consisting of seniors only; and a household that does not pay for its own hot water use. Although these four conditions can significantly affect residential hot water use, and have been noted in other studies, this is the first time that they have been incorporated into a detailed model. This model allows detailed evaluation of the impact of potential efficiency standards for water heaters and other market transformation policies.

  11. Temporal and spatial patterns of micropollutants in urban receiving waters

    Energy Technology Data Exchange (ETDEWEB)

    Musolff, Andreas, E-mail: andreas.musolff@ufz.d [UFZ - Helmholtz Centre for Environmental Research, Department of Hydrogeology, Permoserstr. 15, 04318 Leipzig (Germany); Leschik, Sebastian, E-mail: sebastian.leschik@ufz.d [UFZ - Helmholtz Centre for Environmental Research, Department of Hydrogeology, Permoserstr. 15, 04318 Leipzig (Germany); Moeder, Monika, E-mail: monika.moeder@ufz.d [UFZ - Helmholtz Centre for Environmental Research, Department of Analytical Chemistry, Permoserstr. 15, 04318 Leipzig (Germany); Strauch, Gerhard, E-mail: gerhard.strauch@ufz.d [UFZ - Helmholtz Centre for Environmental Research, Department of Hydrogeology, Permoserstr. 15, 04318 Leipzig (Germany); Reinstorf, Frido, E-mail: frido.reinstorf@hs-magdeburg.d [University of Applied Sciences Magdeburg-Stendal, Department of Water and Waste Management, Breitscheidstr. 2, 39114 Magdeburg (Germany); Schirmer, Mario, E-mail: mario.schirmer@eawag.c [Eawag, The Swiss Federal Institute of Aquatic Science and Technology, Department of Water Resources and Drinking Water, Ueberlandstr. 133, 8600 Duebendorf (Switzerland)


    Based on a monitoring program over the course of a year, we characterize the temporal and spatial distribution of selected micropollutants in an urban watershed within the city of Leipzig, Germany. Micropollutants revealed a ubiquitous presence in untreated and treated wastewater, surface water and groundwater. The loads of 4-nonylphenol in the effluents of the municipal wastewater treatment plant followed a seasonal trend, whereas the loads of all other micropollutants were highly variable and not correlated to seasons. In the surface water, load seasonality of caffeine, galaxolide and tonalide resulted from a rapid removal with increased water temperature. The loads of 4-nonylphenol and of caffeine in the colder months increased when rainfall occurred. In the groundwater, complex spatial and temporal patterns were apparent and were related to varying input, retardation and removal processes. As a consequence, an assessment of micropollutants in urban waters should consider different micropollutants' temporal and spatial variability. - Micropollutants in urban receiving waters are characterized by variable temporal and spatial concentration and load patterns that have to be considered in risk assessments.

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

    Leake, Stanley A.; Pool, Donald R.


    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.

  13. 库姆塔格沙漠东北缘浅层地下水补给来源%Phreatic Water Recharged Source on the Northeast of Kumtag Desert

    Institute of Scientific and Technical Information of China (English)

    李文赞; 严平; 刘永刚; 丁连刚; 俄有浩


    Recharge sources of the phreatic and surface water in the Sule River Valley have been investigated with hydrological,geochemical and isotopic techniques.Stable isotope compositions of shallow groundwater and surface water in the valley evolve from a starting composition which is more depleted.Waters in the valley and surface water in adjacent areas appear unconnected based on chemical composition and radiocarbon activities.Hydrogeological evidence points toward the Qilian Mountain as a recharge zone,which is consistent with the tracer results.The concentration of Tritium is very low,indicating that the age of the shallow groundwater is very old.The results also reveal that the water resources are very sensitive to the environment,which is relevant for the resources management in this ecologically sensitive area.%依据库姆塔格沙漠东北缘地表水和地下水水文、水化学和同位素相关数据,分析探讨了沙漠东北缘地下水的主要补给来源。结果表明,水体与周边流域地表水并无直接联系,主要受到南部山区贫重同位素水体的补给,但补给过程缓慢,因此,对周边地区水资源的开发非常敏感。根据地势条件和水文地质条件,祁连山沿党河洪积扇到谷地冲湖积平原可能存在一条地下水补给路径,冰雪融水和降水渗透到地下,沿党河洪积扇最终补给到疏勒河谷地。

  14. Reflector modelization in neutronic and optimization methods applied to fuel loading pattern; Modelisation du reflecteur en neutronique et methodes d`optimisation appliquees aux plans de rechargement

    Energy Technology Data Exchange (ETDEWEB)

    Argaud, J.P.


    I Physical description of P.W.R nuclear core can be handled by multigroup neutronic diffusion model. We are interested in two problems, using the same approach for the optimization aspect. To deal with some differences between calculations and measurements, the question of their reduction is then introduced. A reflector parameters identification from core measurements is then purposed, the reflector being at the present time the less known part of core diffusion model. This approach conducts to study the reflector model, in particular by an analysis of its transport origin. It leads finally to a new model of reflector described by boundary operators using an integral formulation on the core/reflector interface. That is on this new model that a parameter identification formulation of calculations-measurements differences reduction is given, using an adjoint state formulation to minimize errors by a gradient method. Furthermore, nuclear fuel reload of P.W.R core needs an optimal distribution of fuel assemblies, namely a loading pattern. This combinatorial optimization problem is then expressed as a cost function minimization, the cost function describing the power spatial distribution. Various methods (linear programming, simulated annealing,...), used to solve this problem, are detailed, given in particular a practical search example. A new approach is then proposed, using the gradient of the cost function to direct the search in the patterns discrete space. Final results of complete patterns search trials are presented, and compared to those obtained by other methods. In particular the results are obtained very quickly. (author). 81 refs., 55 figs., 5 appends.

  15. A New Qualitative Typology to Classify Treading Water Movement Patterns

    Directory of Open Access Journals (Sweden)

    Christophe Schnitzler, Chris Button, James L. Croft, Ludovic Seifert


    Full Text Available This study proposes a new qualitative typology that can be used to classify learners treading water into different skill-based categories. To establish the typology, 38 participants were videotaped while treading water and their movement patterns were qualitatively analyzed by two experienced biomechanists. 13 sport science students were then asked to classify eight of the original participants after watching a brief tutorial video about how to use the typology. To examine intra-rater consistency, each participant was presented in a random order three times. Generalizability (G and Decision (D studies were performed to estimate the importance variance due to rater, occasion, video and the interactions between them, and to determine the reliability of the raters’ answers. A typology of five general classes of coordination was defined amongst the original 38 participants. The G-study showed an accurate and reliable assessment of different pattern type, with a percentage of correct classification of 80.1%, an overall Fleiss’ Kappa coefficient K = 0.6, and an overall generalizability φ coefficient of 0.99. This study showed that the new typology proposed to characterize the behaviour of individuals treading water was both accurate and highly reliable. Movement pattern classification using the typology might help practitioners distinguish between different skill-based behaviours and potentially guide instruction of key aquatic survival skills.

  16. Impacts of Future Climate Change and Baltic Sea Level Rise on Groundwater Recharge, Groundwater Levels, and Surface Leakage in the Hanko Aquifer in Southern Finland

    Directory of Open Access Journals (Sweden)

    Samrit Luoma


    Full Text Available The impact of climate change and Baltic Sea level rise on groundwater resources in a shallow, unconfined, low-lying coastal aquifer in Hanko, southern Finland, was assessed using the UZF1 model package coupled with the three-dimensional groundwater flow model MODFLOW to simulate flow from the unsaturated zone through the aquifer. The snow and PET models were used to calculate the surface water availability for infiltration from the precipitation data used in UZF1. Infiltration rate, flow in the unsaturated zone and groundwater recharge were then simulated using UZF1. The simulation data from climate and sea level rise scenarios were compared with present data. The results indicated changes in recharge pattern during 2071–2100, with recharge occurring earlier in winter and early spring. The seasonal impacts of climate change on groundwater recharge were more significant, with surface overflow resulting in flooding during winter and early spring and drought during summer. Rising sea level would cause some parts of the aquifer to be under sea level, compromising groundwater quality due to intrusion of sea water. This, together with increased groundwater recharge, would raise groundwater levels and consequently contribute more surface leakage and potential flooding in the low-lying aquifer.

  17. Ground-water flow related to streamflow and water quality (United States)

    Van Voast, W. A.; Novitzki, R.P.


    A ground-water flow system in southwestern Minnesota illustrates water movement between geologic units and between the land surface and the subsurface. The flow patterns indicate numerous zones of ground-water recharge and discharge controlled by topography, varying thicknesses of geologic units, variation in permeabilities, and the configuration of the basement rock surface. Variations in streamflow along a reach of the Yellow Medicine River agree with the subsurface flow system. Increases and decreases in runoff per square mile correspond, apparently, to ground-water discharge and recharge zones. Ground-water quality variations between calcium sulfate waters typical of the Quaternary drift and sodium chloride waters typical of the Cretaceous rocks are caused by mixing of the two water types. The zones of mixing are in agreement with ground-water flow patterns along the hydrologic section.

  18. Groundwater Modelling For Recharge Estimation Using Satellite Based Evapotranspiration (United States)

    Soheili, Mahmoud; (Tom) Rientjes, T. H. M.; (Christiaan) van der Tol, C.


    Groundwater movement is influenced by several factors and processes in the hydrological cycle, from which, recharge is of high relevance. Since the amount of aquifer extractable water directly relates to the recharge amount, estimation of recharge is a perquisite of groundwater resources management. Recharge is highly affected by water loss mechanisms the major of which is actual evapotranspiration (ETa). It is, therefore, essential to have detailed assessment of ETa impact on groundwater recharge. The objective of this study was to evaluate how recharge was affected when satellite-based evapotranspiration was used instead of in-situ based ETa in the Salland area, the Netherlands. The Methodology for Interactive Planning for Water Management (MIPWA) model setup which includes a groundwater model for the northern part of the Netherlands was used for recharge estimation. The Surface Energy Balance Algorithm for Land (SEBAL) based actual evapotranspiration maps from Waterschap Groot Salland were also used. Comparison of SEBAL based ETa estimates with in-situ abased estimates in the Netherlands showed that these SEBAL estimates were not reliable. As such results could not serve for calibrating root zone parameters in the CAPSIM model. The annual cumulative ETa map produced by the model showed that the maximum amount of evapotranspiration occurs in mixed forest areas in the northeast and a portion of central parts. Estimates ranged from 579 mm to a minimum of 0 mm in the highest elevated areas with woody vegetation in the southeast of the region. Variations in mean seasonal hydraulic head and groundwater level for each layer showed that the hydraulic gradient follows elevation in the Salland area from southeast (maximum) to northwest (minimum) of the region which depicts the groundwater flow direction. The mean seasonal water balance in CAPSIM part was evaluated to represent recharge estimation in the first layer. The highest recharge estimated flux was for autumn

  19. 乌梁素海及其周边地区水源补给关系同位素研究%Isotope study of recharge relationships of water sources in Wuliangsuhai Lake and its surrounding areas

    Institute of Scientific and Technical Information of China (English)


      野外采集乌梁素海及其周边区域的水样和土壤样品,测定样品的δD、δ18 O和ρ(TDS),并以采自南京燕子矶的黄土为样本进行室内降水入渗试验,测试每个土壤样品的含水率和ρ(TDS)。根据试验结果,对乌梁素海以北的色尔腾山地区的降水入渗情况进行分析,对乌梁素海湖水补给来源进行同位素分析,对乌梁素海湖泊周围地下水进行TDS分析。结果表明,乌梁素海以北的色尔腾山地区的大气降水在入渗的过程中大量蒸发,无法有效入渗补给地下水,降水并不是当地地下水的主要补给源,而比当地降水中的氘氧同位素值更负的稳定外部补给源是当地地下水的主要补给源;泉水、井水的δD和δ18 O值比当地降水明显贫化,也表明大气降水并非是地下水的补给源;地下水是乌梁素海的主要补给源,河套灌区排水渠中的水的主要来源是深循环地下水,狼山—日喀则隐伏断裂带中可能存在渗漏通道,西藏内流区的渗漏水通过该通道补给到了内蒙古高原。%Water and soil samples were collected in the field at Wuliangsuhai Lake and its surrounding areas .TheδD,δ18 O, andρ(TDS) of these samples were measured, and an indoor rainfall infiltration test was conducted with loess collected from Yanziji in Nanjing City .The moisture content and ρ(TDS) of each soil profile were tested. Based on the experimental results , the infiltration of precipitation in the Seerteng Hill areas on the north side of Wuliangsuhai Lake was analyzed , and an isotope analysis of the sources of Wuliangsuhai Lake water and theρ(TDS) analysis of surrounding groundwater of Wuliangsuhai Lake were conducted .The results show that the meteoric water of the Seerteng Hill areas evaporates greatly and cannot effectively recharge groundwater ;precipitation is not the main recharge source of the local groundwater; the main source of the local

  20. Using global analysis models of water resources as an initial measure in management proposals concerning the artificial recharge of aquifers; Empleo de modelos de analisis global de recursos hidricos como primera actuacion a emprender en propuestas de gestion que contemplen operaciones de recarga artificial de acuiferos

    Energy Technology Data Exchange (ETDEWEB)

    Murillo, J. M.; Navarro, J. A.


    This paper discusses artificial recharge not as an individual component disconnected from the other elements that make up a system of water resources, but as an integrated part of such a system, one that is interrelated with all the others, such that any action affecting a given element may affect the recharge operation, and vice versa. The methodology applied throughout this study is based on the technique of systems analysis, and makes use of the AQUATOOL software package with respect to assessing guarantees, water availability for the artificial recharge operation and the suitability of the host aquifer. The results obtained show that it is necessary, in the first place, to draw up a global model of water resources, incorporating all the elements that constitute the system; then, taking into account the results obtained, a viability analysis should be made of the artificial recharge operation, by means of a numerical model of the relevant parameters for the aquifer(s) in question. This model should specify in detail the infiltration operation proposed. If deemed appropriate, and either before or after drawing up the parameter model, a pilot artificial recharge plant can be constructed, so that a small-scale assay may be made of specific aspects of the artificial recharge; in any case, such a pilot plant should always be constructed after obtaining the global analysis model of water resources. The practical application described in this paper refers to the Quiebrajano-Viboras water exploitation system, which is located in the province of Jaen (Spain). (Author) 43 refs.

  1. Vegetation effects on event water dynamics - Insights from in-situ stable isotope observations and dye patterns (United States)

    Volkmann, Till; Haberer, Kristine; Gessler, Arthur; Weiler, Markus


    The predicted changes of climate and land-use could have drastic effects on the water balance of ecosystems, particularly under frequent drought and subsequent rewetting conditions. Yet, inference of these effects and related consequences for the structure and functioning of ecosystems, groundwater recharge, leaching of nutrients and pollutants, drinking water availability, and the water cycle is currently impeded by gaps in our understanding of the manifold interactions between vegetation and soil water dynamics. While plants require water and nutrients, they also exert, for instance, important below-ground controls on the distribution and movement of water and chemicals in the rooted soil horizons via uptake and redistribution of water, modification of soil hydraulic properties, and formation of conduits for rapid preferential water flow. This work aims to contribute to fill existing gaps by assessing the effects of different plant types and their rooting systems on the soil water dynamics. Therefore, we conducted artificial drought and subsequent rewetting experiments using isotopically and dye (Brilliant Blue FCF) labeled water on plots of various surface cover (bare soil, grass, beech, oak, vine) established on relatively homogeneous luvisol on loess in southwestern Germany. Detailed insight into the short-term dynamics of event water infiltration and root uptake during the field experiments was facilitated by the application of novel techniques for high-frequency in-situ monitoring of stable isotope signatures in pore and transpiration water using commercial laser-based spectrometers, augmenting conventional observations of soil physicochemical states (soil water content, matric potential, electrical conductivity). The temporal point information is complemented by dye staining profiles, providing a detailed picture of spatial infiltration patterns, and by root density observations. The results of the experiments allow for a comprehensive spatiotemporal

  2. Determining Changes in Groundwater Quality during Managed Aquifer Recharge (United States)

    Gambhir, T.; Houlihan, M.; Fakhreddine, S.; Dadakis, J.; Fendorf, S. E.


    Managed aquifer recharge (MAR) is becoming an increasingly prevalent technology for improving the sustainability of freshwater supply. However, recharge water can alter the geochemical conditions of the aquifer, mobilizing contaminants native to the aquifer sediments. Geochemical alterations on deep (>300 m) injection of highly treated recycled wastewater for MAR has received limited attention. We aim to determine how residual disinfectants used in water treatment processes, specifically the strong oxidants chloramine and hydrogen peroxide, affect metal mobilization within deep injection wells of the Orange County Water District. Furthermore, as the treated recharge water has very low ionic strength (44.6 mg L-1 total dissolved solids), we tested how differing concentrations of magnesium chloride and calcium chloride affected metal mobilization within deep aquifers. Continuous flow experiments were conducted on columns dry packed with sediments from a deep injection MAR site in Orange County, CA. The effluent was analyzed for shifts in water quality, including aqueous concentrations of arsenic, uranium, and chromium. Interaction between the sediment and oxic recharge solution causes naturally-occurring arsenopyrite to repartition onto iron oxides. The stability of arsenic on the newly precipitated iron oxides is dependent on pH changes during recharge.

  3. Analysis of subsurface temperature data to quantify groundwater recharge rates in a closed Altiplano basin, northern Chile (United States)

    Kikuchi, C. P.; Ferré, T. P. A.


    Quantifying groundwater recharge is a fundamental part of groundwater resource assessment and management, and is requisite to determining the safe yield of an aquifer. Natural groundwater recharge in arid and semi-arid regions comprises several mechanisms: in-place, mountain-front, and mountain-block recharge. A field study was undertaken in a high-plain basin in the Altiplano region of northern Chile to quantify the magnitude of in-place and mountain-front recharge. Water fluxes corresponding to both recharge mechanisms were calculated using heat as a natural tracer. To quantify in-place recharge, time-series temperature data in cased boreholes were collected, and the annual fluctuation at multiple depths analyzed to infer the water flux through the unsaturated zone. To quantify mountain-front recharge, time-series temperature data were collected in perennial and ephemeral stream channels. Streambed thermographs were analyzed to determine the onset and duration of flow in ephemeral channels, and the vertical water fluxes into both perennial and ephemeral channels. The point flux estimates in streambeds and the unsaturated zone were upscaled to channel and basin-floor areas to provide comparative estimates of the range of volumetric recharge rates corresponding to each recharge mechanism. The results of this study show that mountain-front recharge is substantially more important than in-place recharge in this basin. The results further demonstrate the worth of time-series subsurface temperature data to characterize both in-place and mountain-front recharge processes.

  4. Forest Transpiration: Resolving Species-Specific Root Water Uptake Patterns (United States)

    Blume, T.; Heidbuechel, I.; Simard, S.; Guntner, A.; Weiler, M.; Stewart, R. D.


    Transpiration and its spatio-temporal variability are still not fully understood, despite their importance for the global water cycle. This is in part due to our inability to measure transpiration comprehensively. Transpiration is usually either estimated with empirical equations based on climatic variables and crop factors, by measuring sap velocities, estimating sap wood area and scaling up to the forest stand based on a number of assumptions or by measuring the integral signal across a footprint with eddy flux towers. All these methods are focused on the cumulated loss of water to the atmosphere and do not provide information on where this water is coming from. In this study, spatio-temporal variability of root water uptake was investigated in a forest in the northeastern German lowlands. The soils are sandy and the depth of the unsaturated zone ranges from 1 to 30 m. We estimated root water uptake from different soil depths, from 0.1 m down to 2 m, based on diurnal fluctuations in soil moisture content during rain-free days. The 15 field sites cover different topographic positions and forest stands: 4 pure stands of both mature and young beech and pine and 9 mixed stands. The resulting daily data set of root water uptake shows that the forest stands differ in total amounts as well as in uptake depth distributions. Temporal dynamics of signal strength within the profile suggest a locally shifting spatial distribution of uptake that changes with water availability. The relationship of these depth-resolved uptake rates to overall soil water availability varies considerably between tree species. Using the physically-based soil hydrological model HYDRUS we investigated to what extent the observed patterns in uptake can be related to soil physical relationships alone and where tree species-specific aspects come into play. We furthermore used the model to test assumptions and estimate uncertainties of this soil moisture based estimation of plant water uptake. The

  5. Using EARTH Model to Estimate Groundwater Recharge at Five Representative Zones in the Hebei Plain, China

    Institute of Scientific and Technical Information of China (English)

    Bingguo Wang; Menggui Jin; Xing Liang


    Accurate estimation of groundwater recharge is essential for efficient and sustainable groundwater management in many semi-arid regions. In this paper, a lumped parameter model (EARTH) was established to simulate the recharge rate and recharge process in typical areas by the ob-servation datum of weather, soil water and groundwater synthetically, and the spatial and temporal variation law of groundwater recharge in the Hebei Plain was revealed. The mean annual recharge rates at LQ, LC, HS, DZ and CZ representative zones are 220.1, 196.7, 34.1, 141.0 and 188.0 mm/a and the recharge coefficients are 26.5%, 22.3%, 7.2%, 20.4%, and 22.0%, respectively. Recharge rate and re-charge coefficient are gradually reduced from piedmont plain to coastal plain. Groundwater recharge appears as only yearly waves, with higher frequency components of the input series filtered by the deep complicated unsaturated zone (such as LC). While at other zones, groundwater recharge series strongly dependent on the daily rainfall and irrigation because of the shallow water table or coarse lithology.

  6. Vegetation induced diel signal and its meaning in recharge and discharge regions (United States)

    Gribovszki, Zoltán; Tóth, Tibor; Csáfordi, Péter; Szabó, András; Móricz, Norbert; Kalicz, Péter


    Afforestation, promoted by the European Union is planned in Hungary in the next decades. One of the most important region for afforestation is the Hungarian Great Plain where the precipitation is far below potential ET so forests can not survive without significant water uptake from shallow groundwater. Diel fluctuations of hydrological variables (e.g., soil moisture, shallow groundwater level, streamflow rate) are rarely investigated in the hydrologic literature although these short-term fluctuations may incorporate useful information (like groundwater uptake) about hydro-ecological systems in shallow groundwater areas. Vegetation induced diel fluctuations are rarely compared under varying hydrologic conditions (such as recharge and discharge zones). In this study, the data of soil moisture and shallow groundwater monitoring under different surface covers (forest and neighboring agricultural plots) in discharge and recharge regions were analyzed to gain a better understanding of the vegetation hydrological impact or water uptake in changing climate. The pilot areas of the study are located in Hungarian Great Plain and in Western Hungary. The water table under the forest displayed a typical night-time recovery in the discharge region, indicating a significant groundwater supply. Certainly, the root system of the forest was able to tap the groundwater in depths measuring a few metres, while the shallower roots of the herbaceous vegetation generally did not reach the groundwater reservoir at these depths. In the recharge zone the water table under the forest showed step-like diel pattern that refer to a lack of additional groundwater supply from below. The low groundwater evapotranspiration of the forest in the recharge zone was due to the lack of the groundwater supply in the recharge area. Similar patterns can be detected in the soil moisture of recharge and discharge zones as well. Our results suggest that local estimations of groundwater evapotranspiration from

  7. 屋面雨水回灌裂隙岩溶水水岩作用实验研究%Laboratory experiment on water-rock interaction of the karst fracture water after recharged with roof rainwater

    Institute of Scientific and Technical Information of China (English)

    朱中竹; 王维平; 蒋颖魁; 周亚群


    Simulation experiment is carried out to test the corrosive interaction between the Ordovician system limestone samples taken from the west campus of the Jinan University with the mixed water of different groundwater to rainwater ratio. The water-rock interaction among the original groundwater, aquifer media and rainwater being recharged is analyzed by means of determination of pH and electrical conductivity as well as several convention ions and using hydro-geochemical modeling software PHREEQC. The results show that ,(1) after the groundwater and rainwater being mixed with each other, the CO2 pressure in the mixed water gradually decreases under the influence of temperature increase and decarbonation along with the oscillation; (2) Ca2+ concentration slightly decreases when mixing ratios of groundwater and rainwater are 9 : 1, 7 : 3 and 5 : 5 respectively, while other ions concentration does not change obviously; (3) saturation indexes of calcite, dolomite and gypsum decrease along with reaction time, and saturation indexes of calcite and dolomite decrease obviously along with the increases of recharging rainwater amount, from 0. 23 -- 0. 39and 0. 05~-0. 97 when the ratio of groundwater to rainwater being 9 : 1 and from -0. 34~-0. 62 and -1. 59~-2. 57 when the ratio of groundwater to rainwater being 1:9 respectively, which indicating that the rainwater is able to increase the corrosion to calcite and dolomite or even the whole aquifer and that the more the rainwater amount, the more obvious and stronger the corrosive effect; (4) rainwater recharge can only lead limited corrosion amount, so it won't cause obvious impact on the stability of the aquifers a-round the well.%在济南大学西校中采集奥陶系灰岩岩样,并设置不同的地下水、雨水混合比例进行室内溶蚀模拟实验.通过pH、电导率及几种常规离子的测定,并利用水文地球化学模拟软件PHREEQC等方法,分析雨水回灌含水层后与原有的地下水以

  8. Identifying Seasonal Groundwater Recharge Using Environmental Stable Isotopes

    Directory of Open Access Journals (Sweden)

    Hsin-Fu Yeh


    Full Text Available In this study, the stable isotope values of oxygen and hydrogen were used to identify the seasonal contribution ratios of precipitation to groundwater recharge in the Hualien River basin of eastern Taiwan. The differences and correlations of isotopes in various water bodies were examined to evaluate the groundwater recharge sources for the Hualian River basin and the interrelations between groundwater and surface water. Proportions of recharge sources were calculated based on the results of the mass balance analysis of the isotope composition of hydrogen and oxygen in the basin. Mountain river water accounted for 83% and plain rainfall accounted for 17% of the groundwater recharge in the Huanlian River basin. Using the mean d-values, a comparison of d-values of precipitation and groundwater indicates the groundwater consists of 75.5% wet seasonal sources and 24.5% dry seasonal sources, representing a distinct seasonal variation of groundwater recharge in the study area. Comparisons between hydrogen and oxygen isotopes in rainwater showed that differences in the amount of rainfall resulted in depleted oxygen and hydrogen isotopes for precipitation in wet seasons as compared to dry seasons. The river water contained more depleted hydrogen and oxygen isotopes than was the case for precipitation, implying that the river water mainly came from the upstream catchment. In addition, the hydrogen and oxygen isotopes in the groundwater slightly deviated from the hydrogen and oxygen isotopic meteoric water line in Huanlian. Therefore, the groundwater in this basin might be a mixture of river water and precipitation, resulting in the effect of the river water recharge being greater than that of rainfall infiltration.

  9. Identification of potential artificial groundwater recharge zones in Northwestern Saudi Arabia using GIS and Boolean logic (United States)

    Zaidi, Faisal K.; Nazzal, Yousef; Ahmed, Izrar; Naeem, Muhammad; Jafri, Muhammad Kamran


    Identifying potential groundwater recharge zones is a pre-requisite for any artificial recharge project. The present study focuses on identifying the potential zones of Artificial Groundwater Recharge (AGR) in Northwestern Saudi Arabia. Parameters including slope, soil texture, vadose zone thickness, groundwater quality (TDS) and type of water bearing formation were integrated in a GIS environment using Boolean logic. The results showed that 17.90% of the total studied area is suitable for AGR. The identified zones were integrated with the land use/land cover map to avoid agricultural and inhabited lands which reduced the total potential area to 14.24%. Geomorphologically the wadi beds are the most suitable sites for recharge. On the basis of the potential AGR zones closeness to the available recharge water supply (rain water, desalinated sea water and treated waste water) the potential zones were classified as Category A (high priority) and Category B (low priority).

  10. Developing empirical monthly groundwater recharge equations based on modeling and remote sensing data - Modeling future groundwater recharge to predict potential climate change impacts (United States)

    Gemitzi, Alexandra; Ajami, Hoori; Richnow, Hans-Hermann


    Groundwater recharge is one of main components of the water budget that is difficult to quantify due to complexity of recharge processes and limited observations. In the present work a simple regression equation for monthly groundwater recharge estimation is developed by relating simulated recharge from a calibrated Soil and Water Assessment tool (SWAT) model to effective precipitation. Monthly groundwater recharge and actual evapotranspiration (AET) were computed by applying a calibrated (SWAT) model for a ten year period (2005-2015) in Vosvozis river basin in NE Greece. SWAT actual evapotranspiration (AET) results were compared to remotely sensed AET values from the MODerate Resolution Imaging Spectroradiometer (MODIS), indicating the integrity of the modeling process. Water isotopes of 2H and 18O, originally presented herein, were used to infer recharge resources in the basin and provided additional evidence of the applicability of the developed formula. Results showed that the developed recharge estimation method can be effectively applied using MODIS evapotranspiration data, without having to adhere to numerical modeling which is many times constrained by the lack of available data especially in poorly gauged basins. Future trends of groundwater recharge up to 2100 using an ensemble of five downscaled climate change projections indicated that annual recharge will increase up to the middle of the present century and gradually decrease thereafter. However, the predicted magnitude is highly variable depending on the Global Climate Model (GCM) used. While winter recharge will likely increase in the future, summer recharge is expected to decrease as a result of temperature rise in the future.

  11. Rechargeable Lithium Metal Cell Project (United States)

    National Aeronautics and Space Administration — PSI proposes to develop a rechargeable lithium metal cell with energy density >400Wh/kg. This represents a >70% increase as compared to similarly constructed...

  12. Patterns and properties of polarized light in air and water. (United States)

    Cronin, Thomas W; Marshall, Justin


    Natural sources of light are at best weakly polarized, but polarization of light is common in natural scenes in the atmosphere, on the surface of the Earth, and underwater. We review the current state of knowledge concerning how polarization and polarization patterns are formed in nature, emphasizing linearly polarized light. Scattering of sunlight or moonlight in the sky often forms a strongly polarized, stable and predictable pattern used by many animals for orientation and navigation throughout the day, at twilight, and on moonlit nights. By contrast, polarization of light in water, while visible in most directions of view, is generally much weaker. In air, the surfaces of natural objects often reflect partially polarized light, but such reflections are rarer underwater, and multiple-path scattering degrades such polarization within metres. Because polarization in both air and water is produced by scattering, visibility through such media can be enhanced using straightforward polarization-based methods of image recovery, and some living visual systems may use similar methods to improve vision in haze or underwater. Although circularly polarized light is rare in nature, it is produced by the surfaces of some animals, where it may be used in specialized systems of communication.

  13. Water Use in Los Angeles, California: Consumption Patterns, Ecosystem Response and Impact on Regional Water Budgets (United States)

    Hogue, T. S.


    The City of Los Angeles relies heavily on external water sources, primarily the Eastern Sierra, Northern California and the Colorado River, and approximately 90% of the City's water supply is snowpack dependent. In recent years, water conservation measures have been implemented in response to regional drought, which include a tiered pricing structure and watering restrictions. As a result of implemented conservation policies, Los Angeles reported the lowest water consumption per capita per day in 2011 among cities over 1 million people in the U.S. This presentation will highlight our ongoing work to better understand the coupling between humans, ecosystems and water across the City of Los Angeles, especially during the recent drought period. Our work is unique in that we integrate social, ecological, and hydrologic data, including ten years of residential water consumption data for the entire city of Los Angeles, extensive groundwater well data, socio-economic information and remote sensing to evaluate relationships as well as spatial and temporal patterns. Developed statistical models demonstrated that Single-Family Residential (SFR) water use across the City is primarily driven by household income, landscape greenness, water rates and water volume allocation,, with higher consumption rates in the northern, warmer and more affluent parts, and lower consumption rates in the less affluent neighborhoods near Downtown. Landscape use also varies greatly across the city, averaging 50% of total SFR. Our evaluation of conservation efforts shows that the combination of mandatory watering restrictions and price increase led to a water reduction of 23%, while voluntary restrictions led to only a 6% reduction in water use. Relationships of water use to ecosystems (greenness) and groundwater variability were also evaluated and will be highlighted. Our ultimate goal is to improve predictions of human-water interactions in order to drive policy change and guide future demand

  14. Enhancement of wadi recharge using dams coupled with aquifer storage and recovery wells

    KAUST Repository

    Missimer, Thomas M. M.


    Wadi channel recharge to the underlying alluvial aquifer is naturally limited by the flashy nature of flood events, evapotranspiration losses of water from the vadose zone, and aquifer heterogeneity, particularly low vertical hydraulic conductivity. Anthropogenic lowering of the water table in many wadi aquifers has also reduced the potential recharge by increasing the thickness of the vadose zone, causing interflow water loss from surface emergence and evaporation. A method to enhance recharge is to slow the flow within wadi channels by placement of dam structures, thereby ponding water and increasing the vertical head gradient to create a more rapid rate of infiltration and percolation. Effectiveness of wadi dams to enhance aquifer recharge reduces over time due to mud deposition within the reservoir caused by storm events. Up to 80 % of the water in old wadi reservoirs is lost to free-surface evaporation before infiltration and recharge can occur. One method to maintain or increase the rate of recharge is to convey clean water by gravity flow from the reservoir down-gradient to artificially recharge the aquifer using existing wells. This type of system is a low-cost and low-energy recharge method which could greatly enhance groundwater storage in wadi aquifers. Modeling results show that existing wells could store up to 1,000 m3/day under gravity-feed conditions and up to 3,900 m3/day with the shut-in of the well to produce a pressurized system. © 2014 Springer-Verlag Berlin Heidelberg.

  15. Aquifer response to recharge-discharge phenomenon: inference from well hydrographs for genetic classification (United States)

    Mukherjee, Arunangshu; Gupta, Anita; Ray, Ranjan Kumar; Tewari, Dinesh


    The continuous groundwater level data emanating from a high-frequency automatic water level recorder installed in a purpose-built piezometer provides a true hydrograph. Analyses of such hydrographs fairly reflect the aquifer character and can be used to draw inference for genetic classification of hard rock aquifers. The signature shape of annual water level fluctuation curve (annual cycle) of a piezometer is due to the specific character of the aquifer and the way it responds to the recharge-discharge phenomenon. The pattern of annual cycle remains identical year after year, although its magnitude may vary with the annual quantum of recharge-discharge. Lithology of the aquifer does not control the shape of the curve. Based on the crest and trough shape, the hard rock aquifers of Peninsular India, where the monsoonal pattern of rainfall occurs, have been classified into genetic groups. It is also found that the nature of the aquifer can be determined by visual comparison of apparent line thickness of the hydrograph, where thin lines denote unconfined aquifer and the apparently thicker lines correspond to confining condition. The response of an aquifer to a pumping event can be identified and separated by its pattern. Thus, the aquifer classification can be automated by adopting the proposed classification scheme.

  16. Groundwater recharge at five representative sites in the Hebei Plain, China. (United States)

    Lu, Xiaohui; Jin, Menggui; van Genuchten, Martinus Th; Wang, Bingguo


    Accurate estimates of groundwater recharge are essential for effective management of groundwater, especially when supplies are limited such as in many arid and semiarid areas. In the Hebei Plain, China, water shortage is increasingly restricting socioeconomic development, especially for agriculture, which heavily relies on groundwater. Human activities have greatly changed groundwater recharge there during the past several decades. To obtain better estimates of recharge in the plain, five representative sites were selected to investigate the effects of irrigation and water table depth on groundwater recharge. At each site, a one-dimensional unsaturated flow model (Hydrus-1D) was calibrated using field data of climate, soil moisture, and groundwater levels. A sensitivity analysis of evapotranspirative fluxes and various soil hydraulic parameters confirmed that fine-textured surface soils generally generate less recharge. Model calculations showed that recharge on average is about 175 mm/year in the piedmont plain to the west, and 133 mm/year in both the central alluvial and lacustrine plains and the coastal plain to the east. Temporal and spatial variations in the recharge processes were significant in response to rainfall and irrigation. Peak time-lags between infiltration (rainfall plus irrigation) and recharge were 18 to 35 days in the piedmont plain and 3 to 5 days in the central alluvial and lacustrine plains, but only 1 or 2 days in the coastal plain. This implies that different time-lags corresponding to different water table depths must be considered when estimating or modeling groundwater recharge.

  17. Vulnerability of shallow ground water and drinking-water wells to nitrate in the United States: Model of predicted nitrate concentration in shallow, recently recharged ground water -- Input data set for fresh surface water withdrawal (gwava-s_swus) (United States)

    U.S. Geological Survey, Department of the Interior — This data set represents the amount of fresh surface water withdrawal for irrigation, in megaliters per day, in the conterminous United States. The data set was used...

  18. Vulnerability of shallow ground water and drinking-water wells to nitrate in the United States: Model of predicted nitrate concentration in shallow, recently recharged ground water -- Input data set for water input (gwava-s_wtin) (United States)

    U.S. Geological Survey, Department of the Interior — This data set represents "water input," the ratio of the total area of irrigated land to precipitation, in square kilometers per centimeter, in the conterminous...

  19. Labile Organic Carbon in Recharge and its Impact on Groundwater Arsenic Concentrations in Bangladesh (United States)

    Neumann, R. B.; Ashfaque, K. N.; Badruzzaman, A. M.; Ali, M.; Shoemaker, J. K.; Harvey, C. F.


    Researchers have puzzled over the origin of dissolved arsenic in the aquifers of the Ganges Delta since widespread arsenic poisoning from groundwater was publicized two decades ago. Previous work has concluded that biological oxidation of organic carbon drives geochemical transformations that mobilize arsenic from sediments; however, the source of the organic carbon that fuels these processes remains controversial. A combined hydrologic and biogeochemical analysis of a typical site in Bangladesh, where constructed ponds and groundwater-irrigated rice fields are the main sources of recharge, shows that only recharge through pond sediments provides the biologically degradable organic carbon that can drive arsenic mobilization. Numerical groundwater simulations as well as chemical and isotopic indicators suggest that contaminated groundwater originates from excavated ponds and that water originating from rice fields is low in arsenic. In fact, rice fields act as an arsenic sink. Irrigation moves arsenic-rich groundwater from the aquifers and deposits it on the rice fields. Most of the deposited arsenic does not return to the aquifers; it is sorbed by the field’s surface soil and bunds, and is swept away in the monsoon floods. The findings indicate that patterns of arsenic contamination in the shallow aquifer are due to recharge-source variation and complex three-dimensional flow.

  20. Chloride-mass-balance for predicting increased recharge after land-use change

    Energy Technology Data Exchange (ETDEWEB)

    Gee, G.W.; Zhang, Z.F.; Tyler, S.W.; Albright, W.H.; Singleton, M.J.


    The chloride-mass-balance (CMB) method has been used extensively to estimate recharge in arid and semi-arid environments. Required data include estimates of annual precipitation, total chloride input (from dry fallout and precipitation), and pore-water chloride concentrations. Typically, CMB has been used to estimate ancient recharge but recharge from recent land-use change has also been documented. Recharge rates below a few mm/yr are reliably detected with CMB; however, estimates above a few mm/yr appear to be less reliable. We tested the CMB method against 26 years of drainage from a 7.6-m-deep lysimeter at a simulated waste-burial ground, located on the Department of Energy s Hanford Site in southeastern Washington State, USA where land-use change has increased recharge rates. Measured drainage from the lysimeter for the past 26 years averaged 62 mm/yr. Precipitation averaged 190 mm/yr with an estimated chloride input of 0.225 mg/L. Initial pore-water chloride concentration was 88 mg/L and decreased to about 6 mg/L after 26 years, while the drainage water decreased to less than 1 mg/L. A recharge estimate made using chloride concentrations in drain water was within 20 percent of the measured drainage rate. In contrast, recharge estimates using 1:1 (water: soil) extracts were lower than actual by factors ranging from 2 to 8 or more. The results suggest that when recharge is above a few mm/yr, soil water extracts can lead to unreliable estimates of recharge. For conditions of elevated recharge, direct sampling of pore water is the preferred method, because chloride concentrations are often 20 to 50 times higher in directly-sampled pore water than in pore-water extracts.

  1. Groundwater recharge measurements in gravel sandy sediments with monolith lysimeter (United States)

    Bracic Zeleznik, Branka; Souvent, Petra; Cencur Curk, Barbara; Zupanc, Vesna


    Ljubljana field aquifer is recharging through precipitation and the river Sava, which has the snow-rain flow regime. The sediments of the aquifer have high permeability and create fast flow as well as high regeneration of the dynamic reserves of the Ljubljana field groundwater resource. Groundwater recharge is vulnerable to climate change and it is very important for drinking water supply management. Water stored in the soil and less permeable layers is important for water availability under extreme weather conditions. Measurements of water percolation through the vadose zone provide important input for groundwater recharge assessment and estimation of contaminant migration from land surface to the groundwater. Knowledge of the processes governing groundwater recharge in the vadose zone is critical to understanding the overall hydrological cycle and quantifying the links between land uses and groundwater quantity and quality. To improve the knowledge on water balance for Ljubljana field aquifer we establish a lysimeter for measurements of processes in unsaturated zone in well field Kleče. The type of lysimeter is a scientific lysimeter designed to solve the water balance equation by measuring the mass of the lysimeter monolith as well as that of outflow tank with high accuracy and high temporal resolution. We evaluated short period data, however the chosen month demonstrates weather extremes of the local climate - relatively dry periods, followed by high precipitation amount. In time of high water usage of vegetation only subsequent substantial precipitation events directly results in water flow towards lower layers. At the same time, gravely layers of the deeper parts of the unsaturated zone have little or no capacity for water retention, and in the event that water line leaves top soil, water flow moves downwards fairly quickly. On one hand this confirms high recharge capacity of Ljubljana field aquifer from precipitation on green areas; on the other hand it

  2. Assessing the recharge of a coastal aquifer using physical observations, tritium, groundwater chemistry and modelling. (United States)

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


    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.

  3. Analyzing and Improving the Water-Table Fluctuation Method of Estimating Groundwater Recharge: Field Considerations Patros, T.B. and Parkin, G.W., School of Environmental Sciences, University of Guelph, Guelph, Ontario, Canada (United States)

    Patros, T.; Parkin, G. W.


    The focus of the project is on measuring and quantifying groundwater recharge (GWR) using the water-table fluctuation (WTF) method. This method requires measuring the change in water-table (WT) height (Δh) during recharge (R) events and volumetric soil specific yield water content (θsy), (&/or) perhaps more correctly volumetric soil fillable water content (θf). The rise in WT can also result from other non-precipitation-related WTF causes (e.g., Lisse effect, temperature variations, barometric, lateral flow, Reverse Wieringermeer effect, encapsulated air, pumping), which must be counted for. The measurement of the storativity (S) terms (θsy) and/or θf) is, indeed, not clear-cut and often they are taken as being constant with depth, time, WT movement (Drying-Wetting & Freezing-Thawing) history and heterogeneity. In fact, these two terms (θsy & θf) are controversial in their definition, thus in their use, in the literature and may either overestimate the R, when using θsy, or underestimate it, when using θf. To resolve some of these questions, a novel-automated method is under development, at the University of Guelph's Elora Research Station (ERS) and Arboretum, along with a novel multi-event time series model. The long-term expected outcomes and significance of this study are; 1. Establishing accuracy in defining and evaluating the θsy and θf and using them accordingly in estimating GWR with the WTF method in order to overcome some of the existing substantial gaps in our knowledge of groundwater (GW) storage variation. 2. Obtaining GWR measurements at the local scale on a year-round basis, which are currently scarce or even completely lacking for many regions of Ontario and thus would provide a valuable database for guiding development of any policy requiring GWR. 3. Using this database to calibrate and test estimates of the spatial and temporal variability in regional-scale (watershed scale) GWR from approximate statistical techniques or deterministic

  4. Recharge from a subsidence crater at the Nevada test site (United States)

    Wilson, G. V.; Ely, D.M.; Hokett, S. L.; Gillespie, D. R.


    Current recharge through the alluvial fans of the Nevada Test Site (NTS) is considered to be negligible, but the impact of more than 400 nuclear subsidence craters on recharge is uncertain. Many of the craters contain a playa region, but the impact of these playas has not been addressed. It was hypothesized that a crater playa would focus infiltration through the surrounding coarser-grained material, thereby increasing recharge. Crater U5a was selected because it represented a worst case for runoff into craters. A borehole was instrumented for neutron logging beneath the playa center and immediately outside the crater. Physical and hydraulic properties were measured along a transect in the crater and outside the crater. Particle-size analysis of the 14.6 m of sediment in the crater and morphological features of the crater suggest that a large ponding event of ≈63000 m3 had occurred since crater formation. Water flow simulations with HYDRUS-2D, which were corroborated by the measured water contents, suggest that the wetting front advanced initially by as much as 30 m yr−1 with a recharge rate 32 yr after the event of 2.5 m yr−1Simulations based on the measured properties of the sediments suggest that infiltration will occur preferentially around the playa perimeter. However, these sediments were shown to effectively restrict future recharge by storing water until removal by evapotranspiration (ET). This work demonstrated that subsidence craters may be self-healing.

  5. Chemical Characteristics, Water Sources and Pathways, and Age Distribution of Ground Water in the Contributing Recharge Area of a Public-Supply Well near Tampa, Florida, 2002-05 (United States)

    Katz, Brian G.; Crandall, Christy A.; Metz, Patricia A.; McBride, William S.; Berndt, Marian P.


    In 2001, the National Water-Quality Assessment (NAWQA) Program of the U.S. Geological Survey began a series of studies on the transport of anthropogenic and natural contaminants (TANC) to public-supply wells. The main goal of the TANC program was to better understand the source, transport, and receptor factors that control contaminant movement to public-supply wells in representative aquifers of the United States. Studies were first conducted at regional scales at four of the eight TANC study areas during 2002-03 and at small (local) scales during 2003-05 in California, Nebraska, Connecticut, and Florida. In the Temple Terrace study area near Tampa, Florida, multiple chemical indicators and geochemical and ground-water flow modeling techniques were used to assess the vulnerability of a public-supply well in the karstic Upper Floridan aquifer to contamination from anthropogenic and naturally occurring contaminants. During 2003-05, water samples were collected from the public-supply well and 13 surrounding monitoring wells that all tap the Upper Floridan aquifer, and from 15 monitoring wells in the overlying surficial aquifer system and the intermediate confining unit that are located within the modeled ground-water contributing recharge area of the public-supply well. Six volatile organic compounds and four pesticides were detected in trace concentrations (well below drinking-water standards) in water from the public-supply well, which had an open interval from 36 to 53 meters below land surface. These contaminants were detected more frequently in water samples from monitoring wells in the overlying clastic surficial aquifer system than in water from monitoring wells in the Upper Floridan aquifer in the study area. Likewise, nitrate-N concentrations in the public-supply well (0.72-1.4 milligrams per liter) were more similar to median concentrations in the oxic surficial aquifer system (2.1 milligrams per liter) than to median nitrate-N concentrations in the anoxic

  6. Groundwater recharge variation under climatic variability in Ajlun area and the recharge zone of Wadi Arab well field - Jordan (United States)

    Raggad, Marwan Al; Alqadi, Mohammad; Magri, Fabien; Disse, Markus; Chiogna, Gabriele


    Pumping of 75 MCM/yr from Ajlun area and Wadi Arab well field has led to diminished groundwater levels in North Jordan and dramatically affects ecosystem services. Climate change compounds these issues by reducing recharge and increasing the ecosystem's hydrological demand. This paper investigates groundwater recharge response to climatic changes in North Jordan by modeling climatic parameters for the time frame 2015 - 2050. Water budget components were modeled through the J2000 hydrological model considering a groundwater recharge of 47 MCM/yr. Statistical downscaling of global circulation models indicated a decline in precipitation of around 30% by the year 2050 with 2.5 and 2 °C increases in maximum and minimum temperature, respectively. Recharge for the year 2050 was recalculated based on the downscaling results to be 27% less than current recharge. Continuous over-pumping with recharge reduction will cause a 30-70% reduction in saturated thickness by the same year. Modeling groundwater resilience under the new conditions showed a severe impact on the study area especially in the central parts which are expected to comprise a semi dry aquifer by 2050.

  7. Quantifying Groundwater Recharge Uncertainty: A Multiple-Model Framework and Case Study (United States)

    Kikuchi, C.; Ferré, T. P. A.


    In practice, it is difficult to estimate groundwater recharge accurately. Despite this challenge, most recharge investigations produce a single, best estimate of recharge. However, there is growing recognition that quantification of natural recharge uncertainty is critical for groundwater management. We present a multiple-model framework for estimating recharge uncertainty. In addition, we show how direct water flux measurements can be used to reduce the uncertainty of estimates of total basin recharge for an arid, closed hydrologic basin in the Atacama Desert, Chile. We first formulated multiple hydrogeologic conceptual models of the basin based on existing data, and implemented each conceptual model for the purpose of conducting numerical simulations. For each conceptual model, groundwater recharge was inversely estimated; then, Null-Space Monte Carlo techniques were used to quantify the uncertainty on the initial estimate of total basin recharge. Second, natural recharge components - including both deep percolation and streambed infiltration - were estimated from field data. Specifically, vertical temperature profiles were measured in monitoring wells and streambeds, and water fluxes were estimated from thermograph analysis. Third, calculated water fluxes were incorporated as prior information to the model calibration and Null-Space Monte Carlo procedures, yielding revised estimates of both total basin recharge and associated uncertainty. The fourth and final component of this study uses value of information analyses to identify potentially informative locations for additional water flux measurements. The uncertainty quantification framework presented here is broadly transferable; furthermore, this research provides an applied example of the extent to which water flux measurements may serve to reduce groundwater recharge uncertainty at the basin scale.

  8. Water supply patterns over Germany under climate change conditions

    Directory of Open Access Journals (Sweden)

    M. H. Tölle


    Full Text Available A large ensemble of 24 bias-corrected and uncorrected regional climate model (RCM simulations is used to investigate climate change impacts on water supply patterns over Germany using the seasonal winter and summer Standardized Precipitation Index (SPI based on 6-month precipitation sums. The climate change signal is studied comparing SPI characteristics for the reference period 1971–2000 with those of the "near" (2036–2065 and the "far" (2071–2100 future. The spread of the climate change signal within the simulation ensemble of bias-corrected versus non-corrected data is discussed. Ensemble scenarios are evaluated against available observation-based data over the reference period 1971–2000. After correcting the model biases, the model ensemble underestimates the variability of the precipitation climatology in the reference period, but replicates the mean characteristics. Projections of water supply patterns based on the SPI for the time periods 2036–2065 and 2071–2100 show wetter winter months during both future time periods. As a result soil drying may be delayed to late spring extending into the summer period, which could have an important effect on sensible heat fluxes. While projections indicate wetting in summer during 2036–2065, drier summers are estimated towards the south-west of Germany for the end of the 21st century. The use of the bias correction intensifies the signal to wetter conditions for both seasons and time periods. The spread in the projection of future water supply patterns between the ensemble members is explored, resulting in high spatial differences that suggest a higher uncertainty of the climate change signal in the southern part of Germany. It is shown that the spread of the climate change signals between SPIs based on single ensemble members is twice as large as the difference between the mean climate change signal of SPIs based on bias-corrected and uncorrected precipitation. This implies that the

  9. Changes in groundwater recharge under projected climate in the upper Colorado River basin (United States)

    Tillman, Fred D.; Gangopadhyay, Subhrendu; Pruitt, Tom


    Understanding groundwater-budget components, particularly groundwater recharge, is important to sustainably manage both groundwater and surface water supplies in the Colorado River basin now and in the future. This study quantifies projected changes in upper Colorado River basin (UCRB) groundwater recharge from recent historical (1950-2015) through future (2016-2099) time periods, using a distributed-parameter groundwater recharge model with downscaled climate data from 97 Coupled Model Intercomparison Project Phase 5 climate projections. Simulated future groundwater recharge in the UCRB is generally expected to be greater than the historical average in most decades. Increases in groundwater recharge in the UCRB are a consequence of projected increases in precipitation, offsetting reductions in recharge that would result from projected increased temperatures.

  10. Changes in groundwater recharge under projected climate in the upper Colorado River basin (United States)

    Tillman, Fred; Gangopadhyay, Subhrendu; Pruitt, Tom


    Understanding groundwater-budget components, particularly groundwater recharge, is important to sustainably manage both groundwater and surface water supplies in the Colorado River basin now and in the future. This study quantifies projected changes in upper Colorado River basin (UCRB) groundwater recharge from recent historical (1950–2015) through future (2016–2099) time periods, using a distributed-parameter groundwater recharge model with downscaled climate data from 97 Coupled Model Intercomparison Project Phase 5 climate projections. Simulated future groundwater recharge in the UCRB is generally expected to be greater than the historical average in most decades. Increases in groundwater recharge in the UCRB are a consequence of projected increases in precipitation, offsetting reductions in recharge that would result from projected increased temperatures.

  11. Water Use Patterns in Vietnamese Hotels: Modeling Toilet and Shower Usage


    Kanako Toyosada; Takayuki Otani; Yasutoshi Shimizu


    Water saving is a key issue in rapidly developing countries, such as Vietnam, that face various water resource management challenges. This study investigated water-use patterns in a hotel in Ho Chi Minh City in Vietnam. It aimed to quantify the efficiency of water-saving devices through modeling toilet and shower usage patterns, including water consumption. The shift in hourly consumption of cold and hot water was also identified. Analysis revealed that, on average, a full toilet flush occurs...

  12. Isotope investigation on groundwater recharge and dynamics in shallow and deep alluvial aquifers of southwest Punjab. (United States)

    Keesari, Tirumalesh; Sharma, Diana A; Rishi, Madhuri S; Pant, Diksha; Mohokar, Hemant V; Jaryal, Ajay Kumar; Sinha, U K


    Groundwater samples collected from the alluvial aquifers of southwest Punjab, both shallow and deep zones were measured for environmental tritium ((3)H) and stable isotopes ((2)H and (18)O) to evaluate the source of recharge and aquifer dynamics. The shallow groundwater shows wide variation in isotopic signature (δ(18)O: -11.3 to -5.0‰) reflecting multiple sources of recharge. The average isotopic signature of shallow groundwaters (δ(18)O: -6.73 ± 1.03‰) is similar to that of local precipitation (-6.98 ± 1.66‰) indicating local precipitation contributes to a large extent compared to other sources. Other sources have isotopically distinct signatures due to either high altitude recharge (canal sources) or evaporative enrichment (irrigation return flow). Deep groundwater shows relatively depleted isotopic signature (δ(18)O: -8.6‰) and doesn't show any evaporation effect as compared to shallow zone indicating recharge from precipitation occurring at relatively higher altitudes. Environmental tritium indicates that both shallow ((3)H: 5 - 10 T.U.) and deeper zone ((3)H: 1.5 - 2.5 T.U.) groundwaters are modern. In general the inter-aquifer connections seem to be unlikely except a few places. Environmental isotope data suggests that shallow groundwater is dynamic, local and prone to changes in land use patterns while deep zone water is derived from distant sources, less dynamic and not impacted by surface manifestations. A conceptual groundwater flow diagram is presented. Copyright © 2017 Elsevier Ltd. All rights reserved.

  13. Simulated effects of ground-water withdrawals and artificial recharge on discharge to streams, springs, and riparian vegetation in the Sierra Vista Subwatershed of the Upper San Pedro Basin, southeastern Arizona (United States)

    Leake, Stanley A.; Pool, Donald R.; Leenhouts, James M.


    In the context of ground-water resources, “capture” or “streamflow depletion” refers to withdrawal-induced changes in inflow to or outflow from an aquifer. These concepts are helpful in understanding the effects of long-term development of ground-water resources. For the Upper San Pedro Basin in Arizona, USA and Sonora, Mexico, a recently developed ground-water flow model is available to help quantify capture of water from the river and riparian system. A common method of analysis is to compute curves of capture and aquifer-storage change for a range of time at select points of interest. This study, however, presents results of a method to show spatial distributions of total change in inflow and outflow from withdrawal or injection for select times of interest. The mapped areal distributions show the effect of a single well in terms of the ratio of the change in boundary flow rate to rate of withdrawal or injection by the well. To the extent that the system responds linearly to ground-water withdrawal or injection, fractional responses in the mapped distributions can be used to quantify response for any withdrawal or injection rate. Capture distributions calculated using the Upper San Pedro model include response to (1) withdrawal in the lower basin-fill aquifer for times of 10 and 50 years following the initiation of pumping from predevelopment conditions and (2) artificial recharge to the water table in the area underlain by the lower basin-fill aquifer after 10 and 50 years. The mapped distributions show that response to withdrawals and injections is greatest near the river/riparian system. Presence of clay layers in the vertical interval between withdrawal locations and the river/riparian system, however, can delay the response.

  14. Recharge sources and hydrogeochemical evolution of groundwater in semiarid and karstic environments: A field study in the Granada Basin (Southern Spain)

    Energy Technology Data Exchange (ETDEWEB)

    Kohfahl, Claus [Freie Universitaet Berlin, Institute of Geological Sciences, Malteserstr. 74-100, D-12249 Berlin (Germany)], E-mail:; Sprenger, Christoph [Freie Universitaet Berlin, Institute of Geological Sciences, Malteserstr. 74-100, D-12249 Berlin (Germany); Herrera, Jose Benavente [Instituto del Agua de la Universidad de Granada, Ramon y Cajal, 4, 18071 Granada (Spain); Meyer, Hanno [Isotope Laboratory of the Alfred Wegener Institute for Polar and Marine Research, Research Unit Potsdam, Telegrafenberg A 43, 14473 Potsdam (Germany); Chacon, Franzisca Fernandez [Dpto. Hidrogeologia y Aguas Subterraneas, Instituto Geologico y Minero de Espana, Oficina de Proyectos, Urb. Alcazar del Genil 4, Edificio Zulema bajo, 18006 Granada (Spain); Pekdeger, Asaf [Freie Universitaet Berlin, Institute of Geological Sciences, Malteserstr. 74-100, D-12249 Berlin (Germany)


    The objective of this study is to refine the understanding of recharge processes in watersheds representative for karstic semiarid areas by means of stable isotope analysis and hydrogeochemistry. The study focuses on the Granada aquifer system which is located in an intramontane basin bounded by high mountain ranges providing elevation differences of almost 2900 m. These altitude gradients lead to important temperature and precipitation gradients and provide excellent conditions for the application of stable isotopes of water whose composition depends mainly on temperature. Samples of rain, snow, surface water and groundwater were collected at 154 locations for stable isotope studies ({delta}{sup 18}O, D) and, in the case of ground- and surface waters, also for major and minor ion analysis. Thirty-seven springs were sampled between 2 and 5 times from October 2004 to March 2005 along an altitudinal gradient from 552 masl in the Granada basin to 2156 masl in Sierra Nevada. Nine groundwater samples were taken from the discharge of operating wells in the Granada basin which are all located between 540 and 728 masl. The two main rivers were monitored every 2-3 weeks at three different altitudes. Rainfall being scarce during the sampling period, precipitation could only be sampled during four rainfall events. Calculated recharge altitudes of springs showed that source areas of mainly snowmelt recharge are generally located between 1600 and 2000 masl. The isotope compositions of spring water indicate water sources from the western Mediterranean as well as from the Atlantic without indicating a seasonal trend. The isotope pattern of the Quaternary aquifer reflects the spatial separation of different sources of recharge which occur mainly by bankfiltration of the main rivers. Isotopic signatures in the southeastern part of the aquifer indicate a considerable recharge contribution by subsurface flow discharged from the adjacent carbonate aquifer. No evaporation effects due

  15. Fate of human viruses in groundwater recharge systems

    Energy Technology Data Exchange (ETDEWEB)

    Vaughn, J.M.; Landry, E.F.


    The overall objective of this research program was to determine the ability of a well-managed tertiary effluent-recharge system to return virologically acceptable water to the groundwater aquifer. The study assessed the quality of waters renovated by indigenous recharge operations and investigated a number of virus-soil interrelationships. The elucidation of the interactions led to the establishment of basin operating criteria for optimizing virus removal. Raw influents, chlorinated tertiary effluents, and renovated wastewater from the aquifer directly beneath a uniquely designed recharge test basin were assayed on a weekly basis for the presence of human enteroviruses and coliform bacteria. High concentrations of viruses were routinely isolated from influents but were isolated only on four occasions from tertiary-treated sewage effluents. In spite of the high quality effluent being recharged, viruses were isolated from the groundwater observation well, indicating their ability to penetrate the unsaturated zone. Results of poliovirus seeding experiments carried out in the test basin clearly indicated the need to operate recharge basins at low (e.g. 1 cm/h) infiltration rates in areas having soil types similar to those found at the study site. The method selected for reducing the test basin infiltration rate involved clogging the basin surface with settled organic material from highly turbid effluent. Alternative methods for slowing infiltration rates are discussed in the text.

  16. Field experiments and numerical simulations of confined aquifer response to multi-cycle recharge-recovery process through a well (United States)

    Wang, Jianxiu; Wu, Yuanbin; Zhang, Xingsheng; Liu, Yan; Yang, Tianliang; Feng, Bo


    SummaryShanghai is one of the cities suffering from land subsidence in China. Land subsidence has caused serious financial losses. Thus, artificial recharge measures have been adopted to compensate the drawdown in shallow, confined aquifers and thereby control land subsidence. In this study, a multi-cycle recharge-recovery field experiment was performed to investigate the response of a shallow, confined aquifer to artificial recharge through a well. In the experiment, a series of recharge-recovery cycles with different recharge volumes and durations, with and without artificial pressure, were performed. The water levels monitored in the recharge and observation wells indicated the response of the aquifer to the multi-cycle recharge-recovery process. Meanwhile, a finite-difference method (FDM) numerical model was established, and its parameters were obtained via a reversed numerical analysis on the experimental data. The responses of the shallow, confined aquifer to the multi-cycle recharge-recovery process were simulated in detail using the model. The calculation results showed that the water level dropped significantly when the recharge ended. Moreover, the efficiency of a multi-cycle recharge was found to be higher than that of a concentrated one under the same recharge volume and time. The relationship between recharge frequency and efficiency, expressed as H = 0.29498 f0.40163 and R2 = 0.97264, respectively, was obtained through the FDM numerical simulation. In the recharge intervals, the optimal recharge efficiency was achieved when the water level rose to 40% of the peak.

  17. Numerical assessment of ASR recharge using small-diameter wells and surface basins (United States)

    Händel, Falk; Liu, Gaisheng; Dietrich, Peter; Liedl, Rudolf; Butler, James J.


    Aquifer storage and recovery (ASR) methods are increasingly used to overcome the temporal imbalance between water demand and availability. Common ASR recharge methods utilize large-diameter injection wells or surface infiltration basins and trenches, and can be costly to implement. A new low-cost ASR recharge method is currently being developed. This approach is based on recharge via gravity in small-diameter wells installed with direct-push (DP) technology. Numerical modeling is used here to assess the potential of this new approach under conditions commonly faced in field settings. The primary objective is to investigate if a battery of small-diameter DP wells can serve as a viable alternative to a surface basin under typical field conditions, while the secondary objective is to assess which subsurface parameters have the greatest control on DP well performance. Simulation results indicate that gravity recharge via small-diameter wells appears to have a distinct advantage over recharge via surface infiltration basins. For example, two 0.05-m shallow vadose-zone wells with 9-m screens can recharge water at a greater rate than a 60 m2 basin. Also, results reveal that, contrary to an infiltration basin, the recharge rate in a DP well has a much stronger dependence on the horizontal component of hydraulic conductivity than on the vertical component. Moreover, near-surface layers of low hydraulic conductivity, which can significantly reduce the recharge capacity of a surface basin, have a relatively small impact on the recharge capacity of a well as long as a significant portion of the well screen is installed below those layers. Given that installation and operation costs can be low in comparison to common ASR recharge methods, this new approach appears to have great potential for recharging good quality water in shallow unconsolidated aquifers. A field investigation has recently been initiated to follow up the findings of this simulation assessment.

  18. Recharge Response Functions

    Directory of Open Access Journals (Sweden)

    A. Calver


    Full Text Available This paper explores the establishment of transfer functions for describing the annual oscillation of unconfined aquifer water levels in response to effective precipitation. A simple saturated zone representation is developed to accompany the unsaturated zone mechanism. Practical examples are drawn from a sample of sites from the chalk and the Permo-Triassic sandstones of England and Wales. Modelled water levels are in many cases good. The technique is most appropriate within the usual range of fluctuation of aquifer water level, with no great change in influence of abstractions, and when it is acceptable to approximate the complexity of unsaturated zone processes in practical analysis.

  19. Food consumption patterns and their effect on water requirement in China

    NARCIS (Netherlands)

    Liu, J.; Savenije, H.H.G.


    It is widely recognized that food consumption patterns significantly impact water requirements. The aim of this paper is to quantify how food consumption patterns influence water requirements in China. The findings show that per capita water requirement for food (CWRF) has increased from 255 m3 cap-

  20. Seasonality of Groundwater Recharge in the Basin and Range Province, Western North America (United States)

    Neff, K. L.; Meixner, T.; Ajami, H.; De La Cruz, L.


    For water-scarce communities in the western U.S., it is critical to understand groundwater recharge regimes and how those regimes might shift in the face of climate change and impact groundwater resources. Watersheds in the Basin and Range Geological Province are characterized by a variable precipitation regime of wet winters and variable summer precipitation. The relative contributions to groundwater recharge by summer and winter precipitation vary throughout the province, with winter precipitation recharge dominant in the northern parts of the region, and recharge from summer monsoonal precipitation playing a more significant role in the south, where the North American Monsoon (NAM) extends its influence. Stable water isotope data of groundwater and seasonal precipitation from sites in Sonora, Mexico and the U.S. states of California, Nevada, Utah, Arizona, Colorado, New Mexico, and Texas were examined to estimate and compare groundwater recharge seasonality throughout the region. Contributions of winter precipitation to annual recharge vary from 69% ± 41% in the southernmost Río San Miguel Basin in Sonora, Mexico, to 100% ± 36% in the westernmost Mojave Desert of California. The Normalized Seasonal Wetness Index (NSWI), a simple water budget method for estimating recharge seasonality from climatic data, was shown to approximate recharge seasonality well in several winter precipitation-dominated systems, but less well in basins with significant summer precipitation.

  1. Isotope Characteristics of Groundwater and Its Recharge Water in Zhangye Basin%张掖盆地地下水及其补给水源的同位素特征

    Institute of Scientific and Technical Information of China (English)

    连英立; 张光辉; 聂振龙; 刘春华


    为了进一步查明干旱区张掖盆地地下水资源可利用性,在大量野外调查采样和同位素测试资料基础上,结合当地水文地质条件和地下水埋藏状况,应用环境同位素方法,研究了张掖盆地山前单一含水层分布区(戈壁带)潜水及其溢出带以下多层含水层分布区(细土平原)潜水和承压水的同位素特征和补给来源.研究结果表明,在祁连山前的单层结构含水层分布区的潜水氢氧同位素特征与上游山区河水近同,表明该区潜水主要来自出山河水补给,源于祁连山区现代降水和冰雪融水补给,更新较快;细土平原潜水的补给主要来自戈壁带潜水通过泉水溢出和灌溉水补给的河水,受蒸发影响比较显著,所以明显不同于戈壁带潜水同位素特征,其3H含量较低、δ18O和δD较轻.该盆地承压水的3H和14C含量更低,δ18O和δD更轻,反映地下水形成时间较早,更新较慢,源于比较寒冷或高海拔环境水源的较早期补给.因此,充分利用祁连山前戈壁带巨厚卵砾石层的强渗透性和地下水调蓄功能,与地表水优化联合调蓄和合理利用,将有利于张掖盆地地下水资源可持续利用.%In order to further identify the availability of groundwater in the arid area of Zhangye basin, based on the groundwater investigation samplings and isotope testing data, combined with hydrogeological conditions and groundwater buried conditions, using environmental isotope methods, the shallow groundwater and confined groundwater's isotope characteristics and its recharge water in different aquifer distributions are studied. The results show that, the single-layer structure aquifer in the front of Qilian mountain piedmont area, the shallow groundwater and upstream river water have the same hydrogen and oxygen isotope characteristics. This indicates that the shallow groundwater in this area is mainly recharged by mountainous runoff, and the groundwater's renewable rate

  2. Impacts of thickening unsaturated zone on groundwater recharge in the North China Plain (United States)

    Cao, Guoliang; Scanlon, Bridget R.; Han, Dongmei; Zheng, Chunmiao


    Unsustainable groundwater development shown by rapid groundwater depletion in the North China Plain (NCP) underscores the need to quantify spatiotemporal variability in groundwater recharge for improved management of the resource. The objective of this study was to assess spatiotemporal variability in recharge in response to thickening of the unsaturated zone in the NCP. Recharge was estimated by linking a soil water balance (SWB) model, on the basis of monthly meteorological data, irrigation applications, and soil moisture monitoring data (1993-2008), to the water table using a deep unsaturated zone flow model. The dynamic bottom boundary (water table) position was provided by the saturated zone flow component, which simulates regional pumping. The model results clearly indicate the effects of unsaturated zone thickening on both temporal distribution and magnitude of recharge: smoothing temporal variability in recharge, and increasing unsaturated storage and lag time between percolation and recharge. The thickening unsaturated zone can result in average recharge reduction of up to ∼70% in loam soils with water table declines ⩾30 m. Declining groundwater levels with irrigation sourced by groundwater converts percolation to unsaturated zone storage, averaging 14 mm equivalent water depth per year in mostly loam soil over the study period, accounting for ∼30% of the saturated groundwater storage depletion. This study demonstrates that, in thickening unsaturated zones, modeling approaches that directly equate deep drainage with recharge will overestimate the amount and underestimate the time lag between percolation and recharge, emphasizing the importance of more realistic simulation of the continuity of unsaturated and saturated storage to provide more reliable estimates of spatiotemporal variability in recharge.

  3. Flow pattern and related chemical quality of ground water in the "500-foot" sand in the Memphis area, Tennessee (United States)

    Bell, Edwin Allen; Nyman, Dale J.


    The '500-foot' sand is the major source of water supply for the Memphis area. Thick layers of impervious clay above and below the sand confine the water in the aquifer under artesian pressure and also protect the aquifer from contamination. Recharge from rainfall enters the '500-foot' sand in the outcrop, or intake area south and east of Memphis. Recharge from other aquifers enters the sand wherever the confining beds are breached or absent. Some of the recharge that enters the '500-foot' sand in eastern Arkansas moves down the gradients created by pumping in the Memphis area. All discharge from the '500-foot' sand in the Memphis area results from well pumping. Since 1886 continuous withdrawals at gradually increasing rates of pumping have lowered water levels and altered hydraulic gradients in the area. These withdrawals have resulted in changes in direction and velocity of movement of water through the '500-foot' sand. Water in the sand in the southeaster n part of the Memphis area normally moves from the (outcrop area east and south of Memphis northwestward toward points of withdrawal. In the northwestern part of the area, water moves southeastward toward points of withdrawal. A flow-net analysis of the aquifer shows that the rate of water movement through the '500-foot' sand in 1964, toward the major cones of depression in the Memphis area, was about 350 feet per year, or 1 mile in 15 years. A flow-net analysis projected for the year 1975 indicates the rate will increase by about 20 percent in the 12-year period 1964-75. Water in the '500-foot' sand in the Memphis area is generally a calcium magnesium sodium bicarbonate type. It is soft, low in dissolved solids, high in concentrations of iron and carbon dioxide, and slightly to moderately corrosive. The softest and least mineralized water occurs in the southeastern part of the area, and the water becomes slightly harder and more mineralized as it moves downdip toward Memphis. The hardest and most mineralized

  4. Monitoring and modeling infiltration–recharge dynamics of managed aquifer recharge with desalinated seawater

    Directory of Open Access Journals (Sweden)

    Y. Ganot


    Full Text Available We study the relation between surface infiltration and groundwater recharge during managed aquifer recharge (MAR with desalinated seawater in an infiltration pond, at the Menashe site that overlies the northern part of the Israeli Coastal Aquifer. We monitor infiltration dynamics at multiple scales (up to the scale of the entire pond by measuring the ponding depth, sediment water content and groundwater levels, using pressure sensors, single-ring infiltrometers, soil sensors, and observation wells. During a month (January 2015 of continuous intensive MAR (2.45  ×  106 m3 discharged to a 10.7 ha area, groundwater level has risen by 17 m attaining full connection with the pond, while average infiltration rates declined by almost 2 orders of magnitude (from  ∼  11 to  ∼  0.4 m d−1. This reduction can be explained solely by the lithology of the unsaturated zone that includes relatively low-permeability sediments. Clogging processes at the pond-surface – abundant in many MAR operations – are negated by the high-quality desalinated seawater (turbidity  ∼  0.2 NTU, total dissolved solids  ∼  120 mg L−1 or negligible compared to the low-permeability layers. Recharge during infiltration was estimated reasonably well by simple analytical models, whereas a numerical model was used for estimating groundwater recharge after the end of infiltration. It was found that a calibrated numerical model with a one-dimensional representative sediment profile is able to capture MAR dynamics, including temporal reduction of infiltration rates, drainage and groundwater recharge. Measured infiltration rates of an independent MAR event (January 2016 fitted well to those calculated by the calibrated numerical model, showing the model validity. The successful quantification methodologies of the temporal groundwater recharge are useful for MAR practitioners and can serve as an input for groundwater flow models.

  5. Urban Network Implications On Groundwater Recharge (United States)

    Duque, J.; Chambel, A.

    Urbanisation has had a major impact on groundwater beneath Évora city (South Portu- gal). Évora is an ancient city and the growth of impermeable areas due to urbanisation has lead to a reduction in groundwater recharge. The specific type of residential land use has a major influence on the permeability of the recharge area. The use of ground- water inside the city of Évora is largely for particular gardening and small farming supplies. In the oldest part of the city (inside of the city walls) there is little use of groundwater, while in the part of the city outside the city walls usage is more effec- tive. This study provides evidence that the municipality or particular people can use groundwater to irrigate the majority gardens, instead of using cleaned water from the Monte Novo Dam. This will also provide a solution to the control of pollution that occurs due to losses from the sewerage system of the city.

  6. Groundwater recharge mechanisms inferred from isoscapes in a complex tropical mountainous region (United States)

    Sánchez-Murillo, Ricardo; Birkel, Christian


    Stable isotope variations and groundwater recharge mechanisms remain poorly understood across the tropics, particularly in Central America. Here stable isotopes (δ18O and δ2H) in groundwater, surface water, and rainfall are used to produce high-resolution (100 m2 grid) isoscapes for Costa Rica, from which an isotope ratio of precipitation to groundwater (P/GW) is estimated to elucidate the dominant groundwater recharge processes. Spatially, groundwater and surface water isotope ratios depict the strong orographic separation into the Caribbean and Pacific slopes induced by moisture transport directly from the Caribbean Sea and the eastern tropical Pacific Ocean. P/GW isotope ratios reveal that groundwater recharge is biased toward intensive and more depleted monthly rainfall across the Pacific slope with clear evidence of secondary evaporation indicating slower soil matrix recharge processes. On the other hand, P/GW isotope ratios indicate a weak influence of secondary evaporation across the Caribbean slope suggesting rapid recharge via preferential flow paths.

  7. Groundwater suitability recharge zones modelling - A GIS application (United States)

    Dabral, S.; Bhatt, B.; Joshi, J. P.; Sharma, N.


    Groundwater quality in Gujarat state is highly variable and due to multiplicity of factors viz. influenced by direct sea water encroachment, inherent sediment salinity, water logging, overexploitation leading to overall deterioration in ground water quality, coupled with domestic and industrial pollution etc. The groundwater scenario in the state is not very encouraging due to imbalance between recharge and groundwater exploitation. Further, the demand for water has increased manifold owing to agricultural, industrial and domestic requirement and this has led to water scarcity in many parts of the state, which is likely to become more severe in coming future due to both natural and manmade factors. Therefore, sustainable development of groundwater resource requires precise quantitative assessment based on reasonably valid scientific principles. Hence, delineation of groundwater potential zones (GWPZ), has acquired great significance. The present study focuses on the integrated Geospatial and Multi-Criteria Decision Making (MCDM) techniques to determine the most important contributing factors that affect the groundwater resources and also to delineate the potential zones for groundwater recharge. The multiple thematic layers of influencing parameters viz. geology, geomorphology, soil, slope, drainage density and land use, weightages were assigned to the each factor according to their relative importance as per subject experts opinion owing to the natural setup of the region. The Analytical Hierarchy Process (AHP) was applied to these factors and potential recharge zones were identified. The study area for the assessment of groundwater recharge potential zones is Mahi-Narmada inter-stream region of Gujarat state. The study shows that around 28 % region has the excellent suitability of the ground water recharge.

  8. Distinguishing and estimating recharge to karst springs in snow and glacier dominated mountainous basins of the western Himalaya, India (United States)

    Jeelani, Ghulam; Shah, Rouf A.; Deshpande, Rajendrakumar D.; Fryar, Alan E.; Perrin, Jerome; Mukherjee, Abhijit


    Recharge assessment is a challenge in snow and glacier dominated Himalayan basins. Quantification of recharge to karst springs in these complex geological environments is important both for hydrologic understanding and for effective water resource management. We used spring hydrographs and environmental tracers (isotopes and solutes) to distinguish and estimate the sources of spring water and to identify the flow paths of the recharging waters in three mountainous basins of the western Himalaya. The karst springs are perennial with high discharge amplitudes. The results indicate that ambient temperature has a strong influence on the hydrological behavior of the springs. Although the spring flow is dominantly controlled by the melting of snow and/or glaciers, rain events produce sharp spikes in spring hydrographs. The facies patterns in springs within the Bringi basin (Ca-HCO3) and the Liddar basin (Ca-HCO3 and Ca-Mg-HCO3) suggest flow dominantly through limestone and dolomite. Higher concentrations of SO42- and Na+ in warm springs of the Kuthar basin indicate flow through carbonate, silicate and other rocks. The isotopic composition (δ18O, δ2H) of precipitation, snowpacks, glacier melt and karst springs show wide variation both in space and time, and are strongly influenced by the basin relief and meteorology. The tracer-based two- and three-component mixing models suggest that the snowmelt dominantly contributes to the spring flow (55-96%), followed by glacier melt (5-36%) and rain (4-34%). Based on tracer tests with good recovery rates, springs are dominantly recharged through point sources rather than by diffuse infiltration. Changes in the timing, form, and amount of winter precipitation substantially affect the timing and magnitude of spring discharge during the rest of the year.

  9. Evaluation of Recharge Potential at Crater U5a (WISHBONE)

    Energy Technology Data Exchange (ETDEWEB)

    Richard H. French; Samuel L. Hokett


    Radionuclides are present both below and above the water table at the Nevada Test Site (NTS), as the result of underground nuclear testing. Mobilization and transport of radionuclides from the vadose zone is a complex process that is influenced by the solubility and sorption characteristics of the individual radionuclides, as well as the soil water flux. On the NTS, subsidence craters resulting from testing underground nuclear weapons are numerous, and many intercept surface water flows. Because craters collect surface water above the sub-surface point of device detonation, these craters may provide a mechanism for surface water to recharge the groundwater aquifer system underlying the NTS. Given this situation, there is a potential for the captured water to introduce contaminants into the groundwater system. Crater U5a (WISHBONE), located in Frenchman Flat, was selected for study because of its potentially large drainage area, and significant erosional features, which suggested that it has captured more runoff than other craters in the Frenchman Flat area. Recharge conditions were studied in subsidence crater U5a by first drilling boreholes and analyzing the collected soil cores to determine the soil properties and moisture conditions. This information, coupled with a 32-year precipitation record, was used to conduct surface and vaodse zone modeling. Surface water modeling predicted that approximately 13 ponding events had occurred during the life of the crater. Vadose zone modeling indicated that since the crater's formation approximately 5,900 m3 of water were captured by the crater. Of this total, approximately 5,200 m3 of potential recahrge may have occurred, and the best estimates of annual average potential recharge rates lie between 36 and 188 cm of water per year. The term potential is used here to indicate that the water is not technically recharged because it has not yet reached the water table.

  10. Reusable Energy and Power Sources: Rechargeable Batteries (United States)

    Hsiung, Steve C.; Ritz, John M.


    Rechargeable batteries are very popular within consumer electronics. If one uses a cell phone or portable electric tool, she/he understands the need to have a reliable product and the need to remember to use the recharging systems that follow a cycle of charge/discharge. Rechargeable batteries are being called "green" energy sources. They are a…

  11. Managed Aquifer Recharge in Italy: present and prospects. (United States)

    Rossetto, Rudy


    On October the 3rd 2014, a one-day Workshop on Managed Aquifer Recharge (MAR) experiences in Italy took place at the GEOFLUID fair in Piacenza. It was organized within the framework of the EIP AG 128 - MAR Solutions - Managed Aquifer Recharge Strategies and Actions and the EU FPVII MARSOL. The event aimed at showcasing present experiences on MAR in Italy while at the same time starting a network among all the Institutions involved. In this contribution, we discuss the state of MAR application in Italy and summarize the outcomes of that event. In Italy aquifer recharge is traditionally applied unintentionally, by increasing riverbank filtration or because of excess irrigation. A certain interest for artificial recharge of aquifers arose at the end of the '70s and the beginning of the '80s and tests have been carried out in Tuscany, Veneto and Friuli Venezia Giulia. During the last years some projects on aquifer recharge were co-financed by the European Commission mainly through the LIFE program. Nearly all of them use the terminology of artificial recharge instead of MAR. They are: - TRUST (Tool for regional - scale assessment of groundwater storage improvement in adaptation to climate change, LIFE07 ENV/IT/000475; Marsala 2014); - AQUOR (Implementation of a water saving and artificial recharging participated strategy for the quantitative groundwater layer rebalance of the upper Vicenza's plain - LIFE 2010 ENV/IT/380; Mezzalira et al. 2014); - WARBO (Water re-born - artificial recharge: innovative technologies for the sustainable management of water resources, LIFE10 ENV/IT/000394; 2014). While the TRUST project dealt in general with aquifer recharge, AQUOR and WARBO focused essentially on small scale demonstration plants. Within the EU FPVII-ENV-2013 MARSOL project (Demonstrating Managed Aquifer Recharge as a Solution to Water Scarcity and Drought; 2014), a dedicated monitoring and decision support system is under development to manage recharge at a large scale

  12. Land cover controls on depression-focused recharge: an example from southern Ontario (United States)

    Buttle, J. M.; Greenwood, W. J.


    The Oak Ridges Moraine (ORM) is a critical hydrogeologic feature in southern Ontario. Although previous research has highlighted the implications of spatially-focused recharge in closed topographic depressions for regional groundwater resources, such depression-focused recharge (DFR) has not been empirically demonstrated on the ORM. Permeable surficial sands and gravels mantling much of the ORM imply that water fluxes will largely be vertical recharge rather than lateral downslope transfer into depressions. Nevertheless, lateral fluxes may occur in winter and spring, when concrete frost development encourages surface runoff of rainfall and snowmelt. The potential for DFR was examined under forest and agricultural land cover with similar soils and surficial geology. Soil water contents, soil temperatures and ground frost thickness were measured at the crest and base of closed depressions in two agricultural fields and two forest stands on permeable ORM outcrops. Recharge from late-fall to the end of spring snowmelt was estimated via 1-d water balances and surface-applied bromide tracing. Both forest and agricultural sites experienced soil freezing; however, greater soil water contents prior to freeze-up at the latter led to concrete soil frost development. This resulted in lateral movement of snowmelt and rainfall into topographic depressions and surface ponding, which did not occur in forest depressions. Water balance recharge exceeded estimates from the bromide tracer approach at all locations; nevertheless, both methods indicated DRF exceeded recharge at the depression crest in agricultural areas with little difference in forest areas. Water balance estimates suggest winter-spring DFR (1300 - 2000 mm) is 3-5× recharge on level agricultural sites. Differences in the potential for DFR between agricultural and forest land covers have important implications for the spatial variability of recharge fluxes and the quality of recharging water on the ORM.

  13. Alkaline solid polymer electrolytes and their application to rechargeable batteries; Electrolytes solides polymeres alcalins application aux generateurs electrochimiques rechargeables

    Energy Technology Data Exchange (ETDEWEB)

    Guinot, S.


    A new family of solid polymer electrolytes (SPE) based on polyoxyethylene (POE), KOH and water is investigated in view of its use in rechargeable batteries. After a short review on rechargeable batteries, the preparation of various electrolyte compositions is described. Their characterization by differential scanning calorimetry (DSC), thermogravimetric analysis, X-ray diffraction and microscopy confirm a multi-phasic structure. Conductivity measurements give values up to 10 sup -3 S cm sup -1 at room temperature. Their use in cells with nickel as negative electrode and cadmium or zinc as positive electrode has been tested; cycling possibility has been shown to be satisfactory. (C.B.) 113 refs.

  14. Judgement of mine water recharge source using stable isotope A case study of 1st mine of Pingyu%利用稳定同位素判断矿井水补给来源——以平禹一矿为例

    Institute of Scientific and Technical Information of China (English)

    潘国营; 张坤; 王佩璐; 刘江明


    用环境同位素技术研究地下水的补给是当前国内外较为新颖有效的方法之一.本文对研究区93个水样的稳定同位素180值和D值进行了分析和计算.研究结果表明:矿区的岩溶水(包括矿井水)主要是来源于山区大气降水的补给;平禹一矿岩溶水主要来自于矿区北部和西北部山区岩溶水的侧向径流,直接水源为白沙水库地区的地下水;白沙水库一带地下水主要补给来源是当地大气降水.研究结果为该矿区采取有效的防治水措施提供了科学依据.%The environmental isotopic technique is one of the new and effective ways to research the groundwater recharge at home and abroad. The paper analysed and calculated the 18O and D of 93 water samples from study area. The results showed that the recharge source to the karst water (including mine water), in mining area is atmospheric precipitation in mountainous area, and the karsr water in 1st mine of Pingyu come from the sidewise runoff at north and northwest the direct recharge source is the groundwater at Baisha Reservior area, and the atmospheric precipitation is the main recharge source to the ground-water of Baisha reservoir area. This research results can provide scientific basis for flood control of Pingyu mining area.

  15. Recharge Rates and Chemistry Beneath Playas of the High Plains Aquifer - A Literature Review and Synthesis (United States)

    Gurdak, Jason J.; Roe, Cassia D.


    Playas are ephemeral, closed-basin wetlands that are important zones of recharge to the High Plains (or Ogallala) aquifer and critical habitat for birds and other wildlife in the otherwise semiarid, shortgrass prairie and agricultural landscape. The ephemeral nature of playas, low regional recharge rates, and a strong reliance on ground water from the High Plains aquifer has prompted many questions regarding the contribution of recharge from playas to the regional aquifer. To address these questions and concerns, the U.S. Geological Survey, in cooperation with the Playa Lakes Joint Venture, present a review and synthesis of the more than 175 publications about recharge rates and chemistry beneath playas and interplaya settings. Although a number of questions remain regarding the controls on recharge rates and chemistry beneath playas, the results from most published studies indicate that recharge rates beneath playas are substantially (1 to 2 orders of magnitude) higher than recharge rates beneath interplaya settings. The synthesis presented here supports the conceptual model that playas are important zones of recharge to the High Plains aquifer and are not strictly evaporative pans. The major findings of this synthesis yield science-based implications for the protection and management of playas and ground-water resources of the High Plains aquifer and directions for future research.

  16. 某水源热泵抽灌试验及建筑物沉降影响分析%Pumpwater & Recharge Experimental of a Water-source Heat Pump and Analysis of Building Settlement Influence

    Institute of Scientific and Technical Information of China (English)



    水源热泵在一些项目中应用时,存在缺乏前期论证、过度开采等问题。文中结合某水源热泵项目开展试验研究工作,通过抽灌试验数据,对场地管井的布置、土壤的渗透系数、影响半径、建筑物的沉降影响进行了分析计算。%The application of ground source heat pump in some projects, there is a lack of pre feasibility studies, overexploiting problems. This paper combined with the experimental research work of a ground source heat pump project, Which analyses the arrangement of the site well、the permeability coefficient of soil、 radius of influence and building settle-ment according to the pumping and recharging water test data.

  17. Basic study of groundwater recharge which aim at preservation of water resources. Study of bio-filter; Suishitsugen no hozen wo mezashita chikasui jinko kan'yo no kiso kenkyu. Bio filter ni kansuru kenkyu

    Energy Technology Data Exchange (ETDEWEB)

    Umemiya, H. [Yamagata University, Yamagata (Japan). Faculty of Engineering; Suzuki, A. [Yamagata University, Yamagata (Japan)


    An experimental study has been made on the effect of bio-filter in a packed bed. By using a packed bed of glass beads in stead of aquifer, groundwater recharge was reappeared. Measurements were made on microorganism number density, COD, turbidity, iron concentration, and pH. Emphasis was placed on the removal effect of COD. The conclusions were as follows. 1) Bio-filter is formed at the upstream end of the packed bed. It is composed of general microorganism and iron bacteria. The number densities of microorganism and iron bacteria are increased with the passage of time and bio-filter is thickly formed. 2) Bio-filter is very useful to COD removal, because organism is consumed by oxidation with iron bacteria and iron, 3) Iron is removed by the physical filter effect of bio-filter and oxidation with iron bacteria. 4) Turbidity is removed by the physical filter effect of bin-filter. 5) Light is an effective system for COD removal. 6) Environmental temperature is usefulness to bio-filter formation and water purification. (author)

  18. Multi-scale experimental programs for estimating groundwater recharge in hydrologically changing basins (United States)

    McIntyre, Neil; Larsen, Josh; Reading, Lucy; Bulovic, Nevenka; Jarihani, Abdollah; Finch, Warren


    Groundwater recharge estimates are required to evaluate sustainable groundwater abstractions and to support groundwater impacts assessments associated with minerals and energy extraction. Increasingly, recharge estimates are also needed for regional and global scale water cycle modelling. This is especially the case in the great arid and semi-arid basins of the world due to increased water scarcity and dependence of ecosystems and livelihoods on their water supplies, and the considerable potential influence of groundwater on the hydrological cycle. Groundwater resources in the semi-arid Surat Basin of south-east Queensland, Australia, support extensive groundwater-dependent ecosystems and have historically been utilised for regional agriculture and urban water-use. Large volumes of water are currently being produced and will continue to do so as a part of coal seam gas extraction. There is considerable uncertainty about the impacts of gas extraction on water resources and the hydrological cycle, and much of this uncertainty stems from our limited knowledge about recharge processes and how to upscale them. Particular questions are about the role of storm events in controlling annual recharge, the relative contributions of local 'recharge zones' versus diffuse recharge and the translation of (relatively easily quantified) shallow drainage estimates to groundwater recharge. A multi-scale recharge research program is addressing these questions, using multiple approaches in estimating groundwater recharge, including plot and catchment scale monitoring, use of remote sensed data and simulation models. Results during the first year of the program have resulted in development of process hypotheses and experimental designs at three field sites representing key gaps in knowledge. The presentation will overview the process of designing the experimental program; how the results from these sites will be integrated with existing knowledge; and how results will be used to advance

  19. Estimating the recharge properties of the deep ocean using noble gases and helium isotopes (United States)

    Loose, Brice; Jenkins, William J.; Moriarty, Roisin; Brown, Peter; Jullion, Loic; Naveira Garabato, Alberto C.; Torres Valdes, Sinhue; Hoppema, Mario; Ballentine, Chris; Meredith, Michael P.


    The distribution of noble gases and helium isotopes in the dense shelf waters of Antarctica reflects the boundary conditions near the ocean surface: air-sea exchange, sea ice formation, and subsurface ice melt. We use a nonlinear least squares solution to determine the value of the recharge temperature and salinity, as well as the excess air injection and glacial meltwater content throughout the water column and in the precursor to Antarctic Bottom Water. The noble gas-derived recharge temperature and salinity in the Weddell Gyre are -1.95°C and 34.95 psu near 5500 m; these cold, salty recharge values are a result of surface cooling as well as brine rejection during sea ice formation in Antarctic polynyas. In comparison, the global value for deep water recharge temperature is -0.44°C at 5500 m, which is 1.5°C warmer than the southern hemisphere deep water recharge temperature, reflecting a distinct contribution from the north Atlantic. The contrast between northern and southern hemisphere recharge properties highlights the impact of sea ice formation on setting the gas properties in southern sourced deep water. Below 1000 m, glacial meltwater averages 3.5‰ by volume and represents greater than 50% of the excess neon and argon found in the water column. These results indicate glacial melt has a nonnegligible impact on the atmospheric gas content of Antarctic Bottom Water.

  20. Temporal and spatial variability of groundwater recharge on Jeju Island, Korea (United States)

    Mair, Alan; Hagedorn, Benjamin; Tillery, Suzanne; El-Kadi, Aly I.; Westenbroek, Stephen; Ha, Kyoochul; Koh, Gi-Won


    Estimates of groundwater recharge spatial and temporal variability are essential inputs to groundwater flow models that are used to test groundwater availability under different management and climate conditions. In this study, a soil water balance analysis was conducted to estimate groundwater recharge on the island of Jeju, Korea, for baseline, drought, and climate-land use change scenarios. The Soil Water Balance (SWB) computer code was used to compute groundwater recharge and other water balance components at a daily time step using a 100 m grid cell size for an 18-year baseline scenario (1992-2009). A 10-year drought scenario was selected from historical precipitation trends (1961-2009), while the climate-land use change scenario was developed using late 21st century climate projections and a change in urban land use. Mean annual recharge under the baseline, drought, and climate-land use scenarios was estimated at 884, 591, and 788 mm, respectively. Under the baseline scenario, mean annual recharge was within the range of previous estimates (825-959 mm) and only slightly lower than the mean of 902 mm. As a fraction of mean annual rainfall, mean annual recharge was computed as only 42% and less than previous estimates of 44-48%. The maximum historical reported annual pumping rate of 241 × 106 m3 equates to 15% of baseline recharge, which is within the range of 14-16% computed from earlier studies. The model does not include a mechanism to account for additional sources of groundwater recharge, such as fog drip, irrigation, and artificial recharge, and may also overestimate evapotranspiration losses. Consequently, the results presented in this study represent a conservative estimate of total recharge.

  1. Removal of Organic Pollutants in Municipal Wastewater for Artificial Groundwater Recharge

    Institute of Scientific and Technical Information of China (English)


    In order to construct a demonstration artificial groundwater recharge system for wastewater reuse in China, three years of laboratory work has been conducted on advanced treatment technologies in combination with soil aquifer treatment of secondary effluent from sewage treatment plants. An effective and inexpensive process was selected, which uses DGB adsorption, PAC coagulation, sedimentation, sand filtration, ozone disinfection, and soil aquifer treatment. The effluent meets the recommended water quality criteria for groundwater recharge. Ozonation is effective for disinfection as well as for water quality improvement. Results showed that the total N in the SAT system remained constant thus the secondary effluent must have a low NH3-N concentration for groundwater recharge.

  2. Response to recharge variation of thin rainwater lenses and their mixing zone with underlying saline groundwater

    Directory of Open Access Journals (Sweden)

    S. Eeman


    Full Text Available In coastal zones with saline groundwater, fresh groundwater lenses may form due to infiltration of rain water. The thickness of both the lens and the mixing zone, determines fresh water availability for plant growth. Due to recharge variation, the thickness of the lens and the mixing zone are not constant, which may adversely affect agricultural and natural vegetation if saline water reaches the root zone during the growing season. In this paper, we study the response of thin lenses and their mixing zone to variation of recharge. The recharge is varied using sinusoids with a range of amplitudes and frequencies. We vary lens characteristics by varying the Rayleigh number and Mass flux ratio of saline and fresh water, as these dominantly influence the thickness of thin lenses and their mixing zone. Numerical results show a linear relation between the normalised lens volume and the main lens and recharge characteristics, enabling an empirical approximation of the variation of lens thickness. Increase of the recharge amplitude causes increase and the increase of recharge frequency causes a decrease in the variation of lens thickness. The average lens thickness is not significantly influenced by these variations in recharge, contrary to the mixing zone thickness. The mixing zone thickness is compared to that of a Fickian mixing regime. A simple relation between the travelled distance of the centre of the mixing zone position due to variations in recharge and the mixing zone thickness is shown to be valid for both a sinusoidal recharge variation and actual records of daily recharge data. Starting from a step response function, convolution can be used to determine the effect of variable recharge in time. For a sinusoidal curve, we can determine delay of lens movement compared to the recharge curve as well as the lens amplitude, derived from the convolution integral. Together the proposed equations provide us with a first order approximation of lens

  3. Response to recharge variation of thin lenses and their mixing zone with underlying saline groundwater

    Directory of Open Access Journals (Sweden)

    S. Eeman


    Full Text Available In coastal zones with saline groundwater, fresh groundwater lenses may form due to infiltration of rain water. The thickness of both the lens and the mixing zone, determines fresh water availability for plant growth. Due to recharge variation, the thickness of the lens and the mixing zone are not constant, which may adversely affect agricultural and natural vegetation if saline water reaches the root zone during the growing season. In this paper, we study the response of thin lenses and their mixing zone to variation of recharge. The recharge is varied using sinusoids with a range of amplitudes and frequencies. We vary lens characteristics by varying the Rayleigh number and Mass flux ratio of saline and fresh water, as these dominantly influence the thickness of thin lenses and their mixing zone. Numerical results show a linear relation between the normalized lens volume and the main lens and recharge characteristics, enabling an analytical approximation of the variation of lens thickness. Increase of the recharge amplitude causes increase, and increase of recharge frequency causes decrease in the variation of lens thickness. The average lens thickness is not significantly influenced by these variations in recharge, contrary to the mixing zone thickness. The mixing zone thickness is compared to that of a Fickian mixing regime. A simple relation between the travelled distance of the center of the mixing zone position due to variations in recharge and the mixing zone thickness is shown to be valid for both a sinusoidal recharge variation and actual records of daily recharge data. Starting from a step response function, convolution can be used to determine the effect of variable recharge in time. For a sinusoidal curve, we can determine delay of lens movement compared to the recharge curve as well as the lens amplitude, derived from the convolution integral. Together the proposed equations provide us with a first order approximation of lens

  4. Vertical distribution patterns of zooplanktivorous fish in a shallow, eutrophic lake, mediated by water transparency

    NARCIS (Netherlands)

    Mous, P.J.; Densen, van W.L.T.; Machiels, M.A.M.


    The vertical distribution pattern (VDP) of fish at shallow sites in eutrophic lake - Lake IJssel, the Netherlands - as affected by water transparency, was examined. The pattern was assessed by pair trawling at three depths and by hydroacoustics from June to August. Water transparency was estimated b

  5. Establishment patterns of water-elm at Catahoula Lake, Louisiana (United States)

    Karen S. Doerr; Sanjeev Joshi; Richard F. Keim


    At Catahoula Lake in central Louisiana, an internationally important lake for water fowl, hydrologic alterations to the surrounding rivers and the lake itself have led to an expansion of water-elm (Planera aquatic J.F. Gmel.) into the lake bed. In this study, we used dendrochronology and aerial photography to quantify the expansion of water-elm in the lake and identify...

  6. Patterns of Tamarix water use during a record drought (United States)

    Nippert, J.B.; Butler, J.J.; Kluitenberg, G.J.; Whittemore, D.O.; Arnold, D.; Spal, S.E.; Ward, J.K.


    During a record drought (2006) in southwest Kansas, USA, we assessed groundwater dynamics in a shallow, unconfined aquifer, along with plant water sources and physiological responses of the invasive riparian shrub Tamarix ramosissima. In early May, diel water table fluctuations indicated evapotranspirative consumption of groundwater by vegetation. During the summer drought, the water table elevation dropped past the lowest position previously recorded. Concurrent with this drop, water table fluctuations abruptly diminished at all wells at which they had previously been observed despite increasing evapotranspirative demand. Following reductions in groundwater fluctuations, volumetric water content declined corresponding to the well-specific depths of the capillary fringe in early May, suggesting a switch from primary dependence on groundwater to vadose-zone water. In at least one well, the fluctuations appear to re-intensify in August, suggesting increased groundwater uptake by Tamarix or other non-senesced species from a deeper water table later in the growing season. Our data suggest that Tamarix can rapidly shift water sources in response to declines in the water table. The use of multiple water sources by Tamarix minimized leaf-level water stress during drought periods. This study illustrates the importance of the previous hydrologic conditions experienced by site vegetation for controlling root establishment at depth and demonstrates the utility of data from high-frequency hydrologic monitoring in the interpretation of plant water sources using isotopic methods. ?? Springer-Verlag 2009.

  7. Static contact angle versus volume of distilled water drop on micro patterned surfaces


    Batichsheva Kseniya; Feoktistov Dmitriy; Ovchinikov Vladimir; Misyura Sergey


    Static contact angle was determined experimentally in the condition of wetting of polished and laser patterned surfaces of stainless steel substrates by distilled water drops with different volumes. In contrast with polished surface, the contact angle was found to depend on drop volume on micro patterned surfaces. In addition, the enhancement of both hydrophilic and hydrophobic properties was observed on laser patterned surfaces.

  8. Echo Meadows Project Winter Artificial Recharge.

    Energy Technology Data Exchange (ETDEWEB)

    Ziari, Fred


    This report discusses the findings of the Echo Meadows Project (BPA Project 2001-015-00). The main purpose of this project is to artificially recharge an alluvial aquifer, WITH water from Umatilla River during the winter high flow period. In turn, this recharged aquifer will discharge an increased flow of cool groundwater back to the river, thereby improving Umatilla River water quality and temperature. A considerable side benefit is that the Umatilla River should improve as a habitat for migration, spanning, and rearing of anadromous and resident fish. The scope of this project is to provide critical baseline information about the Echo Meadows and the associated reach of the Umatilla River. Key elements of information that has been gathered include: (1) Annual and seasonal groundwater levels in the aquifer with an emphasis on the irrigation season, (2) Groundwater hydraulic properties, particularly hydraulic conductivity and specific yield, and (3) Groundwater and Umatilla River water quality including temperature, nutrients and other indicator parameters. One of the major purposes of this data gathering was to develop input to a groundwater model of the area. The purpose of the model is to estimate our ability to recharge this aquifer using water that is only available outside of the irrigation season (December through the end of February) and to estimate the timing of groundwater return flow back to the river. We have found through the data collection and modeling efforts that this reach of the river had historically returned as much as 45 cubic feet per second (cfs) of water to the Umatilla River during the summer and early fall. However, this return flow was reduced to as low as 10 cfs primarily due to reduced quantities of irrigation application, gain in irrigation efficiencies and increased groundwater pumping. Our modeling indicated that it is possible to restore these critical return flows using applied water outside of the irrigation season. We further

  9. Echo Meadows Project Winter Artificial Recharge.

    Energy Technology Data Exchange (ETDEWEB)

    Ziari, Fred


    This report discusses the findings of the Echo Meadows Project (BPA Project 2001-015-00). The main purpose of this project is to artificially recharge an alluvial aquifer, WITH water from Umatilla River during the winter high flow period. In turn, this recharged aquifer will discharge an increased flow of cool groundwater back to the river, thereby improving Umatilla River water quality and temperature. A considerable side benefit is that the Umatilla River should improve as a habitat for migration, spanning, and rearing of anadromous and resident fish. The scope of this project is to provide critical baseline information about the Echo Meadows and the associated reach of the Umatilla River. Key elements of information that has been gathered include: (1) Annual and seasonal groundwater levels in the aquifer with an emphasis on the irrigation season, (2) Groundwater hydraulic properties, particularly hydraulic conductivity and specific yield, and (3) Groundwater and Umatilla River water quality including temperature, nutrients and other indicator parameters. One of the major purposes of this data gathering was to develop input to a groundwater model of the area. The purpose of the model is to estimate our ability to recharge this aquifer using water that is only available outside of the irrigation season (December through the end of February) and to estimate the timing of groundwater return flow back to the river. We have found through the data collection and modeling efforts that this reach of the river had historically returned as much as 45 cubic feet per second (cfs) of water to the Umatilla River during the summer and early fall. However, this return flow was reduced to as low as 10 cfs primarily due to reduced quantities of irrigation application, gain in irrigation efficiencies and increased groundwater pumping. Our modeling indicated that it is possible to restore these critical return flows using applied water outside of the irrigation season. We further

  10. Using Tracer Tests to Estimate Vertical Recharge and Evaluate Influencing Factors for Irrigated Agricultural Systems (United States)

    Lin, D.; Jin, M.; Brusseau, M.; Ma, B.; Liu, Y.


    irrigation experiments showed that recharge increased as irrigation quantity increased. Overall, recharge was lower for the fields with the rotation cultivation of winter wheat and summer maize compared to the aged apple orchard. In general, the irrigation quantity applied was larger than the requirement of the crops. Thus, managing the irrigation regime to insure that irrigation matches crop requirements would be helpful to better preserve groundwater resources and prevent water-table decline. The recharge rates obtained in this study will be used as input in a mathematical modeling effort designed to simulate the regional groundwater system in the North China Plain.

  11. Effects of recharge wells and flow barriers on seawater intrusion. (United States)

    Luyun, Roger; Momii, Kazuro; Nakagawa, Kei


    The installation of recharge wells and subsurface flow barriers are among several strategies proposed to control seawater intrusion on coastal groundwater systems. In this study, we performed laboratory-scale experiments and numerical simulations to determine the effects of the location and application of recharge wells, and of the location and penetration depth of flow barriers, on controlling seawater intrusion in unconfined coastal aquifers. We also compared the experimental results with existing analytical solutions. Our results showed that more effective saltwater repulsion is achieved when the recharge water is injected at the toe of the saltwater wedge. Point injection yields about the same repulsion compared with line injection from a screened well for the same recharge rate. Results for flow barriers showed that more effective saltwater repulsion is achieved with deeper barrier penetration and with barriers located closer to the coast. When the flow barrier is installed inland from the original toe position however, saltwater intrusion increases with deeper barrier penetration. Saltwater repulsion due to flow barrier installation was found to be linearly related to horizontal barrier location and a polynomial function of the barrier penetration depth. Copyright © 2010 The Author(s). Journal compilation © 2010 National Ground Water Association.

  12. Iron-Air Rechargeable Battery (United States)

    Narayan, Sri R. (Inventor); Prakash, G.K. Surya (Inventor); Kindler, Andrew (Inventor)


    Embodiments include an iron-air rechargeable battery having a composite electrode including an iron electrode and a hydrogen electrode integrated therewith. An air electrode is spaced from the iron electrode and an electrolyte is provided in contact with the air electrode and the iron electrodes. Various additives and catalysts are disclosed with respect to the iron electrode, air electrode, and electrolyte for increasing battery efficiency and cycle life.

  13. Impact of artificial recharge on dissolved noble gases in groundwater in California. (United States)

    Cey, Bradley D; Hudson, G Bryant; Moran, Jean E; Scanlon, Bridget R


    Dissolved noble gas concentrations in groundwater can provide valuable information on recharge temperatures and enable 3H-3He age-dating with the use of physically based interpretive models. This study presents a large (905 samples) data set of dissolved noble gas concentrations from drinking water supply wells throughout California, representing a range of physiographic, climatic, and water management conditions. Three common interpretive models (unfractionated air, UA; partial re-equilibration, PR; and closed system equilibrium, CE) produce systematically different recharge temperatures or ages; however, the ability of the different models to fit measured data within measurement uncertainty indicates that goodness-of-fit is not a robust indicator for model appropriateness. Therefore caution is necessary when interpreting model results. Samples from multiple locations contained significantly higher Ne and excess air concentrations than reported in the literature, with maximum excess air tending toward 0.05 cm3 STP g(-1) (deltaNe approximately 400%). Artificial recharge is the most plausible cause of the high excess air concentrations. The ability of artificial recharge to dissolve greater amounts of atmospheric gases has important implications for oxidation-reduction dependent chemical reactions. Measured gas concentration ratios suggest that diffusive degassing may have occurred. Understanding the physical processes controlling gas dissolution during groundwater recharge is critical for optimal management of artificial recharge and for predicting changes in water quality that can occur following artificial recharge.

  14. Groundwater recharge estimation under semi arid climate: Case of Northern Gafsa watershed, Tunisia (United States)

    Melki, Achraf; Abdollahi, Khodayar; Fatahi, Rouhallah; Abida, Habib


    Natural groundwater recharge under semi arid climate, like rainfall, is subjected to large variations in both time and space and is therefore very difficult to predict. Nevertheless, in order to set up any strategy for water resources management in such regions, understanding the groundwater recharge variability is essential. This work is interested in examining the impact of rainfall on the aquifer system recharge in the Northern Gafsa Plain in Tunisia. The study is composed of two main parts. The first is interested in the analysis of rainfall spatial and temporal variability in the study basin while the second is devoted to the simulation of groundwater recharge. Rainfall analysis was performed based on annual precipitation data recorded in 6 rainfall stations over a period of 56 years (1960-2015). Potential evapotranspiration data were also collected from 1960 to 2011 (52 years). The hydrologic distributed model WetSpass was used for the estimation of groundwater recharge. Model calibration was performed based on an assessment of the agreement between the sum of recharge and runoff values estimated by the WetSpass hydrological model and those obtained by the climatic method. This latter is based on the difference calculated between rainfall and potential evapotranspiration recorded at each rainy day. Groundwater recharge estimation, on monthly scale, showed that average annual precipitation (183.3 mm/year) was partitioned to 5, 15.3, 36.8, and 42.8% for interception, runoff, actual evapotranspiration and recharge respectively.

  15. Nutrients, Toxins, and Water in Terrestrial and Aquatic Ecosystems Treated with Sewage Plant Effluents. Final Report of the Upland Recharge Program

    Energy Technology Data Exchange (ETDEWEB)

    Woodwell, G. M.; Ballard, J. T.; Clinton, J.; Pecan, E. V.


    The objective of this work was to appraise the capacity of terrestrial and aquatic plant communities for absorbing and retaining nutrients and organic matter in sewage and for releasing ''clean'' water. Experimental systems included a sere representative of the Eastern Deciduous Forest, a timothy field, two Phalaris arundinacea meadows, a freshwater marsh, a pond, and a marsh-pond complex. Sewage of two qualities was applied at the rate of 5 cm per week; one treatment was equivalent to the release from a primary treatment sewage plant, the second to that from a secondary treatment plant. Under normal circumstances, without the addition of water or nutrients in sewage, the flux of nutrients into the groundwater was greatest under the agricultural communities and least under the late successional forest communities. All the terrestrial communities were net sources of most elements. Because the agricultural communities were fertilized and a substantial fraction of the fertilizer applied remained after the first year, the agricultural communities appeared to be net sinks during the first year of the experiment. The highest concentrations of nutrients in the percolate of the untreated communities commonly occurred in the earliest stages of succession. This relationship was especially conspicuous for nitrogen. Phosphorus and iron appeared to be held tightly within most ecosystems.

  16. Groundwater recharge dynamics in unsaturated fractured chalk: a case study (United States)

    Cherubini, Claudia; Pastore, Nicola; Giasi, Concetta I.; Allegretti, Nicolaetta M.


    The heterogeneity of the unsaturated zone controls its hydraulic response to rainfall and the extent to which pollutants are delayed or attenuated before reaching groundwater. It plays therefore a very important role in the recharge of aquifers and the transfer of pollutants because of the presence of temporary storage zones and preferential flows. A better knowledge of the physical processes in the unsaturated zone would allow an improved assessment of the natural recharge in a heterogeneous aquifer and of its vulnerability to surface-applied pollution. The case study regards the role of the thick unsaturated zone of the Cretaceous chalk aquifer in Picardy (North of France) that controls the hydraulic response to rainfall. In the North Paris Basin, much of the recharge must pass through a regional chalk bed that is composed of a porous matrix with embedded fractures. Different types of conceptual models have been formulated to explain infiltration and recharge processes in the unsaturated fractured rock. The present study analyses the episodic recharge in fractured Chalk aquifer using the kinematic diffusion theory to predict water table fluctuation in response to rainfall. From an analysis of the data, there is the evidence of 1) a seasonal behavior characterized by a constant increase in the water level during the winter/spring period and a recession period, 2) a series of episodic behaviors during the summer/autumn. Kinematic diffusion models are useful for predict preferential fluxes and dynamic conditions. The presented approach conceptualizes the unsaturated flow as a combination of 1) diffusive flow refers to the idealized portion of the pore space of the medium within the flow rate is driven essentially by local gradient of potential; 2) preferential flow by which water moves across macroscopic distances through conduits of macropore length.

  17. Monitoring induced denitrification in an artificial aquifer recharge system. (United States)

    Grau-Martinez, Alba; Torrentó, Clara; Folch, Albert; Domènech, Cristina; Otero, Neus; Soler, Albert


    As demands on groundwater increase, artificial recharge is becoming a common method for enhancing groundwater supply. The Llobregat River is a strategic water supply resource to the Barcelona metropolitan area (Catalonia, NE Spain). Aquifer overexploitation has leaded to both a decrease of groundwater level and seawater intrusion, with the consequent deterioration of water quality. In the middle section of the aquifer, in Sant Vicenç del Horts, decantation and infiltration ponds recharged by water from the Llobregat River (highly affected from wastewater treatment plant effluents), were installed in 2007, in the framework of the ENSAT Life+ project. At the bottom of the infiltration pond, a vegetal compost layer was installed to promote the growth of bacteria, to induce denitrification and to create favourable conditions for contaminant biodegradation. This layer consists on a mixture of compost, aquifer material, clay and iron oxide. Understanding the fate of contaminants, such as nitrate, during artificial aquifer recharge is required to evaluate the impact of artificial recharge in groundwater quality. In order to distinguish the source of nitrate and to evaluate the capability of the organic reactive layer to induce denitrification, a multi-isotopic approach coupled with hydrogeochemical data was performed. Groundwater samples, as well as river samples, were sampled during artificial and natural recharge periods. The isotopic analysis included: δ15N and δ18O of dissolved nitrate, δ34S and δ18O of dissolved sulphate, δ13C of dissolved inorganic carbon, and δ2H and δ18O of water. Dissolved nitrate isotopic composition (δ15NNO3 from +9 to +21 o and δ18ONO3 from +3 to +16 ) demonstrated that heterotrophic denitrification induced by the reactive layer was taking place during the artificial recharge periods. An approximation to the extent of nitrate attenuation was calculated, showing a range between 95 and 99% or between 35 and 45%, by using the extreme

  18. Numerical long-term assessment of managed aquifer recharge from a reservoir into a karst aquifer in Jordan (United States)

    Xanke, Julian; Jourde, Hervé; Liesch, Tanja; Goldscheider, Nico


    In semi-arid regions with high seasonal variability of water availability, adaptive management strategies and technical measures are required to ensure the sustainable use of water resources. In this study, managed recharge of storm water into a karst aquifer and the water level fluctuations related to pumping in a nearby wellfield were simulated at Wadi Wala, Jordan. We used a numerical equivalent porous medium (EPM) approach with specific adaptations to account for the heterogeneity and anisotropy of the karst aquifer. The model domain was vertically projected along the wadi course, resulting in a 2-dimensional model, and subdivided into hydraulic zones representing the karst-specific flow pattern of fast flow and slow depletion. Results show satisfying agreement of measured and simulated groundwater tables from 2002 to 2012 and predict a lowering of the average groundwater table until 2022 of around 2.7 m in the immediate surroundings of the reservoir and an increased depletion towards the wellfield, mainly caused by sedimentation in the reservoir and an associated decrease in infiltration. Abstraction at the wellfield changed considerably over the regarded time period and strongly influences the groundwater fluctuations, which shows the need of improved pumping management and monitoring. The results can serve as a basis for decision makers regarding an optimization of water management at the reservoir and wellfield. Furthermore, the presented numerical approach can be transferred to karst regions with similar physio-geographical conditions to assess managed aquifer recharge.

  19. Estimation of the water volume to be managed in the infrastructure of phase II of the artificial recharge plant in the El Carracillo region, Segovia (western area); Determinacion de los volumenes de agua a gestionar en las infraestructuras de la fase II del proyecto de recarga artificial del acuifero cuaternario de la comarca de El Carracillo, Segovia (sector occidental)

    Energy Technology Data Exchange (ETDEWEB)

    Macias Antequera, C.; Martinez Gamo, R.; Martinez Rubio, J.


    The first hydrogeological investigation for the definition of the Carracillo aquifer (Segovia) was carried out in order to plan the best possible artificial recharge works provided for within the framework of the Royal Decree- Law 9/1998 El Carracillo Aquifer Recharge. Intake and Pipeline Work, Infiltration and Irrigation Adequacy (Segovia) These studies revealed the existence of two regions hydro geologically favourable for water storage from flows derived from the river Cega: the first known as the paleo-landform site located within the irrigation area, and the second area called the storage area located in the eastern sector of the district. In order to exactly estimate the minimum and maximum volume of water that has to be managed in the paleo-landform site over a period of five years, the Tragsa Group has carried out, at the request of the Ministry of Agriculture Fisheries and Food, some of the hydrogeological work, which included the exhaustive follow up of the piezometric behaviour of the aquifer and the detailed analysis of each of the external actions that have a direct influence upon it, such as the useful rain, the artificial recharge, the extraction by pumping, and the overland flow, amongst others. (Author)

  20. A multitracer approach to estimate groundwater residence time distributions at a managed aquifer recharge site (United States)

    Popp, Andrea; Kipfer, Rolf


    Managed aquifer recharge (MAR) has become a common water management tool and serves various purposes such as improving the quality of groundwater (GW). At the study site, the Hardwald in Muttenz (Switzerland), MAR has been implemented in the mid-1950s to overcome increasing water demands. GW is artificially recharged with water from the river Rhine through a system of channels and ponds. The area is surrounded by potential contamination sites such as chemical industry, former landfills, a highway and a freight depot. Furthermore, the area shows a complex hydrogeologic setting with several fault zones and two main aquifers, the Quaternary Rhine gravel aquifer overlying a karstified Upper Muschelkalk limestone aquifer. Water from the deeper limestone aquifer is suspected to contain contaminants originating from the landfills. The fractures might serve as a hydraulic connection between the upper and lower aquifer. Further, groundwater pumping might enhance the mixing of recently infiltrated water with older water from the lower aquifer. Hence, the proximity to potential contamination sites and the complex geologic setting both pose risks for GW pollution and challenge the drinking water production in this area. To guarantee a safe drinking water supply, it is crucial to know the mixing patterns of young and old GW abstracted from the pumping wells. With this study we aim to determine the spatial variability of GW residence time distributions to differentiate between recently infiltrated river water and older groundwater. To reach our objectives, we use a combination of the following tracers to cover a wide range of possible GW ages: (1) radiogenic 222Rn (young water := product 3He (old water := 0.5-50 years); and (3) radiogenic 4He (very old water := 100-1000 years). Additionally, we analysed other dissolved (noble) gases (O2, N2, Ar, Kr) to estimate the amount of excess air and to derive the equilibration temperature. We also sampled for physico-chemical parameters

  1. Nitrogen transformations in wetlands: Effects of water flow patterns

    Energy Technology Data Exchange (ETDEWEB)

    Davidsson, T.


    In this thesis, I have studied nitrogen turnover processes in water meadows. A water meadow is a wetland where water infiltrates through the soil of a grassland field. It is hypothesized that infiltration of water through the soil matrix promotes nutrient transformations compared to surface flow of water, by increasing the contact between water, nutrients, soil organic matter and bacteria. I have studied how the balance between nitrogen removal (denitrification, assimilative uptake, adsorption) and release (mineralization, desorption) processes are affected by water flow characteristics. Mass balance studies and direct denitrification measurements at two field sites showed that, although denitrification was high, net nitrogen removal in the water meadows was poor. This was due to release of ammonium and dissolved organic nitrogen (DON) from the soils. In laboratory studies, using {sup 15}N isotope techniques, I have shown that nitrogen turnover is considerably affected by hydrological conditions and by soil type. Infiltration increased virtually all the nitrogen processes, due to deeper penetration of nitrate and oxygen, and extended zones of turnover processes. On the contrary, soils and sediments with surface water flow, diffusion is the main transfer mechanism. The relation between release and removal processes sometimes resulted in shifts towards net nitrogen production. This occurred in infiltration treatments when ammonium efflux was high in relation to denitrification. It was concluded that ammonium and DON was of soil origin and hence not a product of dissimilatory nitrate reduction to ammonium. Both denitrification potential and mineralization rates were higher in peaty than in sandy soil. Vertical or horizontal subsurface flow is substantial in many wetland types, such as riparian zones, tidal salt marshes, fens, root-zone systems and water meadows. Moreover, any environment where aquatic and terrestrial ecosystems meet, and where water level fluctuates

  2. Water Use Patterns in Vietnamese Hotels: Modeling Toilet and Shower Usage

    Directory of Open Access Journals (Sweden)

    Kanako Toyosada


    Full Text Available Water saving is a key issue in rapidly developing countries, such as Vietnam, that face various water resource management challenges. This study investigated water-use patterns in a hotel in Ho Chi Minh City in Vietnam. It aimed to quantify the efficiency of water-saving devices through modeling toilet and shower usage patterns, including water consumption. The shift in hourly consumption of cold and hot water was also identified. Analysis revealed that, on average, a full toilet flush occurs 3.3 times/day, a half flush 3.0 times/day, water consumption due to shower usage is 48.1 L/day, showering time is 7.3 min/day and the shower water temperature is 37.7 °C. Shifting levels of hot and cold water use revealed high activity in the morning time and that there are two peaks, occurring in the morning and at night.

  3. The effect of different irrigation patterns on rice yield and water consumption

    Institute of Scientific and Technical Information of China (English)

    CHENGuolin; WANGRenmin


    The ecological and physiological water requirement of rice and rice yield was studied under three irrigation patterns, which were A: moist irrigation, remains 70-90% of saturated soil water content except 3-4cm deep water layer in tillering stage in paddy : B : flood irrigation,

  4. Cost-Benefit Analysis of the Managed Aquifer Recharge System for Irrigation under Climate Change Conditions in Southern Spain

    National Research Council Canada - National Science Library

    Carmen Ruperez-Moreno; Julio Perez-Sanchez; Javier Senent-Aparicio; Pilar Flores-Asenjo; Carmen Paz-Aparicio


    .... In the integrated water resource management (IWRM), managed aquifer recharge (MAR) offers efficient solutions to protect, conserve, and ensure survival of aquifers and associated ecosystems, as the Water Framework Directive requires...

  5. Quantity and location of groundwater recharge in the Sacramento Mountains, south-central New Mexico (USA), and their relation to the adjacent Roswell Artesian Basin (United States)

    Rawling, Geoffrey C.; Newton, B. Talon


    The Sacramento Mountains and the adjacent Roswell Artesian Basin, in south-central New Mexico (USA), comprise a regional hydrologic system, wherein recharge in the mountains ultimately supplies water to the confined basin aquifer. Geologic, hydrologic, geochemical, and climatologic data were used to delineate the area of recharge in the southern Sacramento Mountains. The water-table fluctuation and chloride mass-balance methods were used to quantify recharge over a range of spatial and temporal scales. Extrapolation of the quantitative recharge estimates to the entire Sacramento Mountains region allowed comparison with previous recharge estimates for the northern Sacramento Mountains and the Roswell Artesian Basin. Recharge in the Sacramento Mountains is estimated to range from 159.86 × 106 to 209.42 × 106 m3/year. Both the location of recharge and range in estimates is consistent with previous work that suggests that ~75 % of the recharge to the confined aquifer in the Roswell Artesian Basin has moved downgradient through the Yeso Formation from distal recharge areas in the Sacramento Mountains. A smaller recharge component is derived from infiltration of streamflow beneath the major drainages that cross the Pecos Slope, but in the southern Sacramento Mountains much of this water is ultimately derived from spring discharge. Direct recharge across the Pecos Slope between the mountains and the confined basin aquifer is much smaller than either of the other two components.

  6. Patterns, structures and regulations of domestic water cycle systems in China (United States)

    Chu, Junying; Wang, Hao; Wang, Jianhua; Qin, Dayong


    Domestic water cycle systems serving as one critical component of artificial water cycle at the catchment's scale, is so closely related to public healthy, human rights and social-economic development, and has gained the highest priority in strategic water resource and municipal infrastructure planning. In this paper, three basic patterns of domestic water cycle systems are identified and analyzed, including rural domestic water system (i.e. primary level), urban domestic water system (i.e. intermediate level) and metropolitan domestic water system (i.e. senior level), with different "abstract-transport-consume-discharge" mechanisms and micro-components of water consumption (such as drinking, cooking, toilet flushing, showering or cleaning). The rural domestic water system is general simple with three basic "abstract-consume-discharge" mechanisms and micro-components of basic water consumption such as drinking, cooking, washing and sanitation. The urban domestic water system has relative complex mechanisms of "abstract-supply-consume-treatment-discharge" and more micro-components of water consumption such as bath, dishwashing or car washing. The metropolitan domestic water system (i.e. senior level) has the most complex mechanisms by considering internal water reuse, external wastewater reclamation, and nutrient recycling processes. The detailed structures for different water cycle pattern are presented from the aspects of water quantity, wastewater quality and nutrients flow. With the speed up of urbanization and development of social-economy in China, those three basic patterns are interacting, transforming and upgrading. According to the past experiences and current situations, urban domestic water system (i.e. intermediate level) is the dominant pattern based on indicator of system number or system scale. The metropolitan domestic water system (i.e. senior level) is the idealized model for the future development and management. Current domestic water system

  7. An innovative artificial recharge system to enhance groundwater storage in basaltic terrain: example from Maharashtra, India (United States)

    Bhusari, Vijay; Katpatal, Y. B.; Kundal, Pradeep


    The management of groundwater poses challenges in basaltic terrain as its availability is not uniform due to the absence of primary porosity. Indiscriminate excessive withdrawal from shallow as well as deep aquifers for meeting increased demand can be higher than natural recharge, causing imbalance in demand and supply and leading to a scarcity condition. An innovative artificial recharge system has been conceived and implemented to augment the groundwater sources at the villages of Saoli and Sastabad in Wardha district of Maharashtra, India. The scheme involves resectioning of a stream bed to achieve a reverse gradient, building a subsurface dam to arrest subsurface flow, and installation of recharge shafts to recharge the deeper aquifers. The paper focuses on analysis of hydrogeological parameters like porosity, specific yield and transmissivity, and on temporal groundwater status. Results indicate that after the construction of the artificial recharge system, a rise of 0.8-2.8 m was recorded in the pre- and post-monsoon groundwater levels in 12 dug wells in the study area; an increase in the yield was also noticed which solved the drinking water and irrigation problems. Spatial analysis was performed using a geographic information system to demarcate the area of influence of the recharge system due to increase in yields of the wells. The study demonstrates efficacy, technical viability and applicability of an innovative artificial recharge system constructed in an area of basaltic terrain prone to water scarcity.

  8. Ceophysical Surveys over Karst Recharge Features,Illinois,USA

    Institute of Scientific and Technical Information of China (English)


    Karst aquifers supply a significant fraction of the world's drinking water. These types of aquifers are also highly susceptible to pollution from the surface with recharge usually occurring through fractures and solution openings at the bedrock surface. Thickness of the protective soil cover, macropores and openings within the soil cover, and the nature of the weathered bedrock surface all influence infiltration. Recharge openings at the bedrock surface, however, are often covered by unconsolidated sediments, resulting in the inadvertent placement of landfills, unregulated dump sites, tailing piles, waste lagoons and septic systems over recharge zones. In these settings surface geophysical surveys, calibrated by a few soil cores, could be employed to identify these recharge openings, and qualitatively assess the protection afforded by the soil cover. In a test of this hypothesis, geophysical measurements accurately predicted the thickness of unconsolidated deposits overlying karstic dolomite at a site about 100 km south of Chicago, Illinois. Zones of elevated electrical conductivity and high ground-penetrating radar (GPR) attenuation within the sediments coincided with subcropping solutionally-enlarged hydraulically active bedrock fractures. These fractures extend to over 12-m depth, as shown by 2-D inverted resistivity sections and soil coring. Anomalous electromagnetic (EM) conductivity and GPR response may be due to higher soil moisture above these enlarged fractures. An epikarstal conduit at 2.5-m depth was directly identified through a GPR survey. These results suggest that surface geophysical surveys are a viable tool for assessing the susceptibility of shallow karst aquifers to contamination.``

  9. Water footprint of individuals with different diet patterns

    Directory of Open Access Journals (Sweden)

    João Hugo Baracuy da Cunha Campos


    Full Text Available The “water footprint” (WF concept has been recently introduced as an important indicator of human water consumption. WF is defined as the total volume of water used during the production and consumption of goods and services as well as of direct water consumption by humans. The objective of this work was to use the WF concept to analyze vegetarian and non-vegetarian consumers with different levels of family income. A case study was conducted with residents of Caicó city (Brazil in order to estimate total amount of water consumed or polluted while producing the goods and services utilized by these consumers. The results indicated that, on average, the WF of the vegetarian consumer represents 58% of non- vegetarian consumers. The WF of the non-vegetarian female consumer was 10-13% smaller than that of the male consumer while for vegetarian consumers the female’s WF was only 5.8% less than the male’s. The WF of the consumer increases linearly with the family income. A population’s water footprint increases as a function of family income and decreases according to eating habits.

  10. Historical patterns and drivers of global crop water demand. (United States)

    Urban, D.; Lobell, D. B.; Sheffield, J.


    With climate change expected to subject staple crops in major growing regions to increased heat exposure, a critical question for agriculture and global food security is the degree to which crop water demand is also likely to change. Recent work has explored the relationship between extreme temperatures and crop water demand, finding that vapor pressure deficit (VPD), through its dependence on both temperature and humidity, provides a very good meteorological predictor of water stress. However, assessing crop water demand solely through atmospheric conditions ignores the roles of radiation and transpiration efficiency, which are increased through elevated CO2. We provide a 60-year global assessment of crop water demand in the world's major growing areas, comparing trends and drivers across key growing regions. We find that an atmospheric-based demand measure can differ significantly from that of a crop-specific sink-based approach that incorporates radiation and CO2 effects, sometimes enough to reverse the sign of historical trends. We also find that these changes differ significantly by region, and that multi-decadal trends can mask large decadal swings. To our knowledge, our work is the first to use global meteorological datasets in a global analysis of crop water demand, and should serve as a valuable reference for future work examining the interaction of hydrological, temperature, and CO2 changes on crop yields.

  11. Fingerlike wetting patterns in two water-repellent loam soils

    NARCIS (Netherlands)

    Dekker, L.W.; Ritsema, C.J.


    In soils with fingered flow, surface-applied solutes can reach the groundwater more rapidly than in the case of homogeneous wetting. This study was undertaken to demonstrate the occurrence of finger-like wetting patterns in a silt loam soil and a silty clay loam soil, and to investigate the

  12. Groundwater recharge and sustainability in the High Plains aquifer in Kansas, USA (United States)

    Sophocleous, M.


    Sustainable use of groundwater must ensure not only that the future resource is not threatened by overuse, but also that natural environments that depend on the resource, such as stream baseflows, riparian vegetation, aquatic ecosystems, and wetlands are protected. To properly manage groundwater resources, accurate information about the inputs (recharge) and outputs (pumpage and natural discharge) within each groundwater basin is needed so that the long-term behavior of the aquifer and its sustainable yield can be estimated or reassessed. As a first step towards this effort, this work highlights some key groundwater recharge studies in the Kansas High Plains at different scales, such as regional soil-water budget and groundwater modeling studies, county-scale groundwater recharge studies, as well as field-experimental local studies, including some original new findings, with an emphasis on assumptions and limitations as well as on environmental factors affecting recharge processes. The general impact of irrigation and cultivation on recharge is to appreciably increase the amount of recharge, and in many cases to exceed precipitation as the predominant source of recharge. The imbalance between the water input (recharge) to the High Plains aquifer and the output (pumpage and stream baseflows primarily) is shown to be severe, and responses to stabilize the system by reducing water use, increasing irrigation efficiency, adopting water-saving land-use practices, and other measures are outlined. Finally, the basic steps necessary to move towards sustainable use of groundwater in the High Plains are delineated, such as improving the knowledge base, reporting and providing access to information, furthering public education, as well as promoting better understanding of the public's attitudinal motivations; adopting the ecosystem and adaptive management approaches to managing groundwater; further improving water efficiency; exploiting the full potential of dryland and

  13. Managed aquifer recharge with low impact development under a changing climate (Invited) (United States)

    Gurdak, J. J.; Newcomer, M. E.; Sklar, L. S.; Nanus, L.


    Groundwater resources in urban environments are highly vulnerable to human pressures and climate variability and change, and many communities face water shortages and need to find alternative water supplies. Therefore, understanding how low impact development (LID) planning and best management practices (BMPs) affect recharge rates and volumes is important because of the increasing use of LID and BMPs to reduce stormwater runoff and improve surface-water quality. Some BMPs may also enhance recharge, which has often been considered a secondary management benefit. Enhancing the capacity for managed aquifer recharge with stormwater beneath LID is an important step toward the sustainable and conjunctive use of surface and groundwater resources in urban environments. This field and modeling study quantifies urban recharge rates, volumes, and efficiency beneath a BMP infiltration trench and irrigated lawn considering historical El Niño/Southern Oscillation (ENSO) variability and future climate change using simulated precipitation from the Geophysical Fluid Dynamic Laboratory (GFDL) A1F1 climate scenario. Using results from a suite of methods to measure and model recharge beneath a recently installed (2009) BMP infiltration trench, this study addresses three main questions: (1) What are the benefits of measuring recharge using in-situ methods compared to model-based and other simple estimates of recharge beneath a LID BMP? (2) What are recharge rates and volumes beneath the infiltration trench, how do they compare to an irrigated lawn that represents a non-LID source of urban recharge, and what are the important factors controlling recharge beneath the two sites? (3) How effective is the LID BMP in capturing and recharging urban stormwater considering historical ENSO variability and future climate change? We find that in-situ and modeling methods are complementary, particularly for simulating historical and future recharge scenarios, and the in-situ data are critical for

  14. Assessing recharge using remotely sensed data in the Guarani Aquifer System outcrop zone (United States)

    Lucas, M. C.; Oliveira, P. T. S.; Melo, D. D.; Wendland, E.


    Groundwater recharge is an essential hydrology component for sustainable water withdrawal from an aquifer. The Guarani Aquifer System (GAS) is the largest (~1.2 million km2) transboundary groundwater reservoir in South America, supplying freshwater to four countries: Brazil, Argentina, Paraguay and Uruguay. However, recharge in the GAS outcrop zones is one of the least known hydrological variables, in part because studies from hydrological data are scarce or nonexistent. We assess recharge using the water-budget as the difference of precipitation (P) and evapotranspiration (ET). Data is derived from remotely sensed estimates of P (TRMM 3B42 V7) and ET (MOD16) in the Onça Creek watershed over the 2004­-12 period. This is an upland-flat watershed (slope steepness < 1%) dominated by sand soils and representative of the GAS outcrop zones. We compared the remote sensing approach against Water Table Fluctuation (WTF) method and another water-budget using ground-based measurements. Uncertainty propagation analysis were also performed. On monthly basis, TRMM P exhibited a great agreement with ground-based P data (R2 = 0.86 and RMSE = 41 mm). Historical (2004-12) mean(±sd) satellite-based recharge (Rsat) was 537(±224) mm y-1, while ground-based recharge using water-budget (Rgr) and WTF (Rwtf) method was 469 mm y-1 and 311(±150) mm y-1, respectively. We found that ~440 mm y-1 is a reasonable historical mean (between Rsat, Rgr and Rwtf) recharge for the study area over 2004-2012 period. The latter mean recharge estimate is about 29% of the mean historical P (1,514 mm y-1). Our results provide the first insight about an intercomparison of water budget from remote sensing and measured data to estimate recharge in the GAS outcrop zone. These results should be useful for future studies on assessing recharge in the GAS outcrop zones. Since accurate and precise recharge estimation still is a gap, our recharge satellite-based is considered acceptable for the Onça Creek

  15. Valuing quality of vegetation in recharge area of Seruk Spring, Pesanggrahan Valley, Batu City, East Java

    Directory of Open Access Journals (Sweden)



    Full Text Available Yulistyarini T, Sofiah S (2011 Valuing quality of vegetation in recharge area of Seruk Spring, Pesanggrahan Valley, Batu City, East Java. Biodiversitas 12: 229-234. A Seruk spring is one of the springs in Batu city which has water debit less than 1 liter per second. Land use changes of Seruk spring recharge area was occured in 2001. Recharge area of Seruk Spring consists of anthropogenic forest, eucalypts plantation, bamboo forest, pines plantation, horticulture and housing. The aim of this research was to valuing the quality of vegetation which supported ground water recharge in Seruk spring. Quality of vegetation were determined by vegetation structure, diversity, the thickness of litter and C-stock of each land use systems. Forests, eucalypts plantation and bamboo forests had almost same quality of vegetation.

  16. Water quality assessment for Ulansuhai Lake using fuzzy clustering and pattern recognition

    Institute of Scientific and Technical Information of China (English)


    Water quality assessment of lakes is important to determine functional zones of water use. Considering the fuzziness during the partitioning process for lake water quality in an arid area, a multiplex model of fuzzy clustering with pattern recognition was developed by integrating transitive closure method, ISODATA algorithm in fuzzy clustering and fuzzy pattern recognition. The model was applied to partition the Ulansuhai Lake, a typical shallow lake in arid climate zone in the west part of Inner Mongolia, China and grade the condition of water quality divisions. The results showed that the partition well matched the real conditions of the lake, and the method has been proved accurate in the application.

  17. A comparison of recharge rates in aquifers of the United States based on groundwater-age data (United States)

    McMahon, P.B.; Plummer, L.N.; Böhlke, J.K.; Shapiro, S.D.; Hinkle, S.R.


    An overview is presented of existing groundwater-age data and their implications for assessing rates and timescales of recharge in selected unconfined aquifer systems of the United States. Apparent age distributions in aquifers determined from chlorofluorocarbon, sulfur hexafluoride, tritium/helium-3, and radiocarbon measurements from 565 wells in 45 networks were used to calculate groundwater recharge rates. Timescales of recharge were defined by 1,873 distributed tritium measurements and 102 radiocarbon measurements from 27 well networks. Recharge rates ranged from tracers of young groundwater exhibited a significant inverse correlation with mean annual air temperature and a significant positive correlation with mean annual precipitation. Comparison of recharge derived from groundwater ages with recharge derived from stream base-flow evaluation showed similar overall patterns but substantial local differences. Results from this compilation demonstrate that age-based recharge estimates can provide useful insights into spatial and temporal variability in recharge at a national scale and factors controlling that variability. Local age-based recharge estimates provide empirical data and process information that are needed for testing and improving more spatially complete model-based methods.

  18. Surface-Water and Ground-Water Interactions in the Central Everglades, Florida (United States)

    Harvey, Judson W.; Newlin, Jessica T.; Krest, James M.; Choi, Jungyill; Nemeth, Eric A.; Krupa, Steven L.


    Everglades restoration. A century of water management for flood control and water storage in the Everglades resulted in the creation of the Water Conservation Areas (WCAs). Construction of the major canals began in the 1910s and the systems of levees that enclose the basins and structures that move water between basins were largely completed by the 1950s. The abandoned wetlands that remained outside of the Water Conservation areas tended to dry out and subside by 10 feet or more, which created abrupt transitions in land-surface elevations and water levels across the levees. The increases in topographic and hydraulic gradients near the margins of the WCAs, along with rapid pumping of water between basins to achieve management objectives, have together altered the patterns of recharge and discharge in the Everglades. The most evident change is the increase in the magnitude of recharge (on the upgradient side) and discharge (on the downgradient side) of levees separating WCA-2A from other basins or areas outside. Recharge and discharge in the vast interior of WCA-2A also likely have increased, but fluxes in the interior wetlands are more subtle and more difficult to quantify compared with areas close to the levees. Surface-water and ground-water interactions differ in fundamental ways between wetlands near WCA-2A's boundaries and wetlands in the basin's interior. The levees that form the WCA's boundaries have introduced step functions in the topographic and hydraulic gradients that are important as a force to drive water flow across the wetland ground surface. The resulting recharge and discharge fluxes tend to be unidirectional (connecting points of recharge on the upgradient side of the levee with points of discharge on the downgradient side), and fluxes are also relatively steady in magnitude compared with fluxes in the interior. Recharge flow paths are also relatively deep in their extent near levees, with fluxes passing entirely through the 1-m peat layer and inte

  19. Recharge and Aquifer Response: Manukan Island’s Aquifer, Sabah, Malaysia

    Directory of Open Access Journals (Sweden)

    Sarva Mangala Praveena


    Full Text Available Manukan Island is a small island located in North-West of Sabah, Malaysia was used as a case study area for numerical modeling of an aquifer response to recharge and pumping rates. The results in this study present the variations of recharge into the aquifer under the prediction simulations. The recharge rate increases the water level as indicated by hydraulic heads. This shows that it can alter groundwater of Manukan Island which has been suffering from an overexploration in its unconfined the aquifer. The increase in recharge rate (from 600 mm/year to 750 mm/year increases the water level indicated by hydraulic heads. A reduction in pumping rate (from 0.072 m3/day to 0.058 m3/day not only increases the amount of water levels in aquifer but also reduces the supply hence a deficit in supply. The increase in hydraulic heads depends on the percentage reduction of pumping and recharges rates. The well water has 1978.3 mg/L chloride with current pumping (0.072 m3/day and recharge rates (600 mm/year. However, with an increased of recharge rate and current pumping rate it has decreased about 1.13%. In addition, reduction in pumping rate made the chloride concentration decreased about 2.8%. In general, a reduction in pumping with an increase in recharge rate leads to a decreased in chloride concentrations within the vicinity of cone of depression. Next, to further develop the numerical model, the model should focus on climate change variables such as consequences of climate change are increase in air temperature, increase in sea surface temperature, and more extreme weather conditions. These parameters are considered critical parameters for climate change impact modeling in aquifers. The behavior of the aquifer and its sustainable pumping rate can be done by applying a computer modeling component.

  20. Groundwater recharge in different physiognomies of the Brazilian Cerrado (United States)

    Oliveira, P. T. S.; Leite, M.; Mattos, T.; Wendland, E.; Nearing, M. A.


    Since 2014, several cities of southeastern Brazil have grappled with their worst drought in nearly 80 years. To improve water availability in this region, the Brazilian government has studied the possibility of increasing groundwater use, mainly in the Guarani Aquifer System (GAS), the largest (~1.2 million km2) transnational boundary groundwater reservoir in South America. Approximately one half of the outcrop areas of the GAS are located in the Cerrado biome, the main agricultural expansion region in Brazil. Large areas of Cerrado vegetation have been converted into farmland in recent years; however, little attention has been paid to the consequences of this land cover and land use change on groundwater recharge. In this study we assessed groundwater recharge in different physiognomies of the Cerrado located in an outcrop area of the GAS. Water table fluctuations were measured from October 2011 through August 2013, by 64 monitoring wells distributed on five physiognomies of the undisturbed Cerrado. We used 20 (2.2±0.3 m), 20 (4.3±1.4 m), 14 (4.7±1.9 m), 9 (6.2±0.7 m), and 1 (42 m) monitoring wells (and average depth of wells) for "campo limpo" (cerrado grassland), "campo sujo" (shrub cerrado), "campo cerrado" (shrub cerrado), "cerrado sensu stricto" (wooded cerrado), and "cerrado sensu stricto denso" (cerrado woodland), respectively. Recharge was computed for each well using the Water Table Fluctuation method. The measured precipitation for hydrological years 2011-12 and 2012-13 were 1247 mm and 1194 mm, respectively. We found values of average annual recharge of 363 mm, 354 mm, 324 mm, and 315 mm for "campo limpo", "campo sujo","campo cerrado", and "cerrado sensu stricto", respectively. We did not find changes in the water table level in the one well located in the "cerrado sensu stricto denso". The water table in this well was 35 m deep; therefore, the amount of water that eventually reached the saturated zone was not enough to cause a rapid change in the

  1. Groundwater recharge and time lag measurement through Vertosols using impulse response functions (United States)

    Hocking, Mark; Kelly, Bryce F. J.


    Throughout the world there are many stressed aquifers used to support irrigated agriculture. The Condamine River catchment (southern Queensland, Australia) is one example of a globally significant agricultural region where groundwater use has exceeded recharge over the last 50 years. There is a high dependence on groundwater in this catchment, because yearly rainfall is highly variable, and actual evapotranspiration often exceeds rainfall. To better manage the aquifer there is a need to correctly conceptualise the primary inputs and outputs of the system, and characterise the lags in system response to all forcings. In catchment models it is particularly important to correctly proportion diffuse (areal) rainfall recharge and to account for the lag between rainfall and recharge at the water table. Throughout large portions of the Condamine Catchment, groundwater levels are now 20 or more metres below the ground surface. This study aimed to better quantify the lag between rainfall and recharge at the water table using the predefined impulse response function in continuous time method (PIRFICT; von Asmuth et al., 2002; von Asmuth, 2012). The PIRFICT method was applied to 255 multi-decadal groundwater level data sets throughout the catchment. Inputs into the modelling include rainfall, irrigation deep drainage, stream water level, evapotranspiration, and groundwater extractions. As an independent check the PIRFICT model derived diffuse recharge estimates are compared to point lysimeter and geochemical recharge estimates in the Vertosol soils within this catchment. It is estimated using the PIRFICT method that in the Condamine Catchment between 1990 and 2012, the mean rain-derived groundwater recharge is 4.4 mm/year. Mean groundwater response from rainfall was determined to be 5.3 years: range 188 days to 48 years. The recharge estimates are consistent with both geochemical and lysimeter point measurements of recharge. It is concluded that where extensive groundwater


    Prior to urbanization, ground water recharge resulted from infiltration of precipitation through pervious surfaces, including grasslands and woods. This infiltration water was relatively uncontaminated. With urbanization, the permeable soil surface area through which recharge by...

  3. Static contact angle versus volume of distilled water drop on micro patterned surfaces

    Directory of Open Access Journals (Sweden)

    Batichsheva Kseniya


    Full Text Available Static contact angle was determined experimentally in the condition of wetting of polished and laser patterned surfaces of stainless steel substrates by distilled water drops with different volumes. In contrast with polished surface, the contact angle was found to depend on drop volume on micro patterned surfaces. In addition, the enhancement of both hydrophilic and hydrophobic properties was observed on laser patterned surfaces.

  4. Water footprints of nations: water use by people as a function of their consumption pattern

    NARCIS (Netherlands)

    Hoekstra, A.Y.; Chapagain, A.K.


    The water footprint shows the extent of water use in relation to consumption of people. The water footprint of a country is defined as the volume of water needed for the production of the goods and services consumed by the inhabitants of the country. The internal water footprint is the volume of wat

  5. Water footprints of nations: water use by people as a function of their consumption pattern

    NARCIS (Netherlands)

    Hoekstra, Arjen Ysbert; Chapagain, Ashok


    The water footprint shows the extent of water use in relation to consumption of people. The water footprint of a country is defined as the volume of water needed for the production of the goods and services consumed by the inhabitants of the country. The internal water footprint is the volume of

  6. Water footprints of nations: water use by people as a function of their consumption pattern

    NARCIS (Netherlands)

    Hoekstra, Arjen Ysbert; Chapagain, Ashok


    The water footprint shows the extent of water use in relation to consumption of people. The water footprint of a country is defined as the volume of water needed for the production of the goods and services consumed by the inhabitants of the country. The internal water footprint is the volume of wat

  7. Piped water consumption in Ghana: A case study of temporal and spatial patterns of clean water demand relative to alternative water sources in rural small towns. (United States)

    Kulinkina, Alexandra V; Kosinski, Karen C; Liss, Alexander; Adjei, Michael N; Ayamgah, Gilbert A; Webb, Patrick; Gute, David M; Plummer, Jeanine D; Naumova, Elena N


    Continuous access to adequate quantities of safe water is essential for human health and socioeconomic development. Piped water systems (PWSs) are an increasingly common type of water supply in rural African small towns. We assessed temporal and spatial patterns in water consumption from public standpipes of four PWSs in Ghana in order to assess clean water demand relative to other available water sources. Low water consumption was evident in all study towns, which manifested temporally and spatially. Temporal variability in water consumption that is negatively correlated with rainfall is an indicator of rainwater preference when it is available. Furthermore, our findings show that standpipes in close proximity to alternative water sources such as streams and hand-dug wells suffer further reductions in water consumption. Qualitative data suggest that consumer demand in the study towns appears to be driven more by water quantity, accessibility, and perceived aesthetic water quality, as compared to microbiological water quality or price. In settings with chronic under-utilization of improved water sources, increasing water demand through household connections, improving water quality with respect to taste and appropriateness for laundry, and educating residents about health benefits of using piped water should be prioritized. Continued consumer demand and sufficient revenue generation are important attributes of a water service that ensure its function over time. Our findings suggest that analyzing water consumption of existing metered PWSs in combination with qualitative approaches may enable more efficient planning of community-based water supplies and support sustainable development.

  8. Groundwater Recharge, Evapotranspiration and Surface Runoff ...

    African Journals Online (AJOL)


    Department of Earth Science, CNCS, P.O. Box 231, Mekelle University, ... The mean annual groundwater recharge, evapotranspiration and runoff were ... Accordingly, recharge accounts for 12% of the precipitation .... So, to apply the WetSpass for Illala catchment, input of the meteorological grid map ..... Review of Australian.

  9. A rechargeable carbon-oxygen battery

    DEFF Research Database (Denmark)


    The invention relates to a rechargeable battery and a method to operate a rechargeable battery having high efficiency and high energy density for storing energy. The battery stores electrical energy in the bonds of carbon and oxygen atoms by converting carbon dioxide into solid carbon and oxygen....

  10. Transient,spatially-varied recharge for groundwater modeling (United States)

    Assefa, Kibreab; Woodbury, Allan


    and other parts of Canada by using the HELP code. However, HELP has known limitations related with boundary conditions as well as spatial and temporal discretization options, and thus cannot simulate highly variable fluxes near boundaries. The limitations are even more pronounced in semi-arid areas like the Okanagan Basin where upward fluxes can be high, because HELP assumes that water below evaporative zone simply drains to the base of a soil column without accounting for upward fluxes. In addition to these limitations, previous studies that used HELP for recharge estimation, [Towes and Allen, 2009; Jyrkama and Sykes, 2007], did not attempt to verify model performance in their study area. The study here presents an integrated procedure that can help address some of these often neglected modelling challenges. The significance of the method in transient groundwater modeling is demonstrated by applying the spatially and temporally varying recharge boundary condition to a saturated zone groundwater model, MIKESHE [DHI, 2009a]. The water table simulated using this method is found to be within 0.6 m of the observed values, whereas the water levels estimated using uniform recharge boundary condition can fluctuate by as much as 1.6 m. Root mean square errors were estimated at 0.3 and 0.94 respectively.

  11. Groundwater recharge in a semi-arid environment under high climatic variability and over-pumping: Ajlun Highlands example, Jordan. (United States)

    Raggad, Marwan; Salameh, Elias; Magri, Fabien; Siebert, Christian; Roediger, Tino; Moller, Peter


    Jordan's ground water resources are being exploited up to 190% of the safe yield while rainfall rates are decreasing and highly variable, thereby affecting recharge volumes of the aquifers. The Ajlun highlands, forming the northwestern edge of Jordan are characterized by annual rainfall rates exceeding 500 mm, the highest in the country, which leads to accordingly high replenishment of almost the entire groundwater system in northern Jordan. The high recharge and the NW-wards dipping strata lead to a groundwater flow towards the north and northwest, areas which host the vital aquifers of the region. Limited and degraded groundwater recharge combined with growing over-pumping are the main issues that regard the northern groundwater basins, such as Wadi Arab, Yarmouk and the Jordan Valley side basins. To evaluate the groundwater potential under high recharge variability, groundwater recharge was modeled and compared to different Global Circulation Models (GCMs). Groundwater recharge was calculated based on climatic data covering the time period from 1965 to 2014. Recharge modeling was conducted by applying the J2000 water budget model. The simulation of hydrologic processes uses independent parameters that are calculated prior to simulate the recharge flow. The simulations estimate recharge of 47.6 MCM, which is 12% less than the values given by the Jordanian authorities. The low calculated recharge is likely due to an overestimation of the evapotranspiration in areas with high topographic slopes. To examine the variability of groundwater recharge under current climatic conditions, statistical downscaling of global circulation models was conducted for the time period 1965 - 2000. Data for the time period 2001 - 2014 was used for the model validation. Results indicated a decline of 18.7% in precipitation by the year 2050 with an increase of 1.7 and 2.2 degrees in maximum and minimum temperatures respectively. Accordingly recharge for the year 2050 is 27% less than

  12. Urban recharge beneath low impact development and effects of climate variability and change (United States)

    Newcomer, Michelle E.; Gurdak, Jason J.; Sklar, Leonard S.; Nanus, Leora


    low impact development (LID) planning and best management practices (BMPs) effects on recharge is important because of the increasing use of LID BMPs to reduce storm water runoff and improve surface-water quality. LID BMPs are microscale, decentralized management techniques such as vegetated systems, pervious pavement, and infiltration trenches to capture, reduce, filter, and slow storm water runoff. Some BMPs may enhance recharge, which has often been considered a secondary management benefit. Here we report results of a field and HYDRUS-2D modeling study in San Francisco, California, USA to quantify urban recharge rates, volumes, and efficiency beneath a LID BMP infiltration trench and irrigated lawn considering historical El Niño/Southern Oscillation (ENSO) variability and future climate change using simulated precipitation from the Geophysical Fluid Dynamic Laboratory (GFDL) A1F1 climate scenario. We find that in situ and modeling methods are complementary, particularly for simulating historical and future recharge scenarios, and the in situ data are critical for accurately estimating recharge under current conditions. Observed (2011-2012) and future (2099-2100) recharge rates beneath the infiltration trench (1750-3710 mm yr-1) were an order of magnitude greater than beneath the irrigated lawn (130-730 mm yr-1). Beneath the infiltration trench, recharge rates ranged from 1390 to 5840 mm yr-1 and averaged 3410 mm yr-1 for El Niño years (1954-2012) and from 1540 to 3330 mm yr-1 and averaged 2430 mm yr-1 for La Niña years. We demonstrate a clear benefit for recharge and local groundwater resources using LID BMPs.

  13. Recharge of an Unconfined Pumice Aquifer: Winter Rainfall Versus Snow Pack, South-central Oregon (United States)

    Cummings, M. L.; Weatherford, J. M.; Eibert, D.


    Walker Rim study area, an uplifted fault block east of the Cascade Range, south-central Oregon, exceeds 1580 m elevation and includes Round Meadow-Sellers Marsh closed basin, and headwaters of Upper Klamath Basin, Deschutes Basin, and Christmas Lake Valley in the Great Basin. The water-bearing unit is 2.8 to 3.0 m thick Plinian pumice fall from the Holocene eruption of Mount Mazama, Cascade Range. The perched pumice aquifer is underlain by low permeability regolith and bedrock. Disruption of the internal continuity of the Plinian pumice fall by fluvial and lacustrine processes resulted in hydrogeologic environments that include fens, wet meadows, and areas of shallow water table. Slopes are low and surface and groundwater pathways follow patterns inherited from the pre-eruption landscape. Discharge for streams and springs and depth to water table measured in open-ended piezometers slotted in the pumice aquifer have been measured between March and October, WY 2011 through WY2015. Yearly occupation on same date has been conducted for middle April, June 1st, and end of October. WY2011 and WY2012 received more precipitation than the 30 year average while WY2014 was the third driest year in 30 years of record. WY2014 and WY2015 provide an interesting contrast. Drought conditions dominated WY2014 while WY2015 was distinct in that the normal cold-season snow pack was replaced by rainfall. Cumulative precipitation exceeded the 30-year average between October and March. The pumice aquifer of wet meadows and areas of shallow water table experienced little recharge in WY2015. Persistence of widespread diffuse discharge from fens declined by middle summer as potentiometric surfaces lowered into confining peat layers or in some settings into the pumice aquifer. Recharge of the perched pumice aquifer in rain-dominated WY2015 was similar to or less than in the snow-dominated drought of WY2014. Rain falling on frozen ground drove runoff rather than aquifer recharge.

  14. Field Investigation of a New Recharge Approach for ASR Projects in Near-Surface Aquifers. (United States)

    Liu, Gaisheng; Knobbe, Steven; Reboulet, Edward C; Whittemore, Donald O; Händel, Falk; Butler, James J


    Aquifer storage and recovery (ASR) is the artificial recharge and temporary storage of water in an aquifer when water is abundant, and recovery of all or a portion of that water when it is needed. One key limiting factor that still hinders the effectiveness of ASR is the high costs of constructing, maintaining, and operating the artificial recharge systems. Here we investigate a new recharge method for ASR in near-surface unconsolidated aquifers that uses small-diameter, low-cost wells installed with direct-push (DP) technology. The effectiveness of a DP well for ASR recharge is compared with that of a surface infiltration basin at a field site in north-central Kansas. The performance of the surface basin was poor at the site due to the presence of a shallow continuous clay layer, identified with DP profiling methods, that constrained the downward movement of infiltrated water and significantly reduced the basin recharge capacity. The DP well penetrated through this clay layer and was able to recharge water by gravity alone at a much higher rate. Most importantly, the costs of the DP well, including both the construction and land costs, were only a small fraction of those for the infiltration basin. This low-cost approach could significantly expand the applicability of ASR as a water resources management tool to entities with limited fiscal resources, such as many small municipalities and rural communities. The results of this investigation demonstrate the great potential of DP wells as a new recharge option for ASR projects in near-surface unconsolidated aquifers.


    Institute of Scientific and Technical Information of China (English)


    Flow patterns of liquid-gas two-phase flow were experimentally investigated. The experiments were carried out in both vertical and horizontal capillary tubes having inner diameters of 1.60 mm. The working liquid was the mixture of water and Sodium Dodecyl Benzoyl Sulfate (SDBS). The working gas was Nitrogen. For the water/SDBS mixture-gas flow in the vertical capillary tube, flow-pattern transitions occurred at lower flow velocities than those for the water-gas flow in the same tube. For the water/SDBS mixture-gas flow in the horizontal capillary tube, surface tension had little effect on the bubbly-intermittent transition and had only slight effect on the plug-slug and slug-annular transitions. However, surface tension had significant effect on the wavy stratified flow regime. The wavy stratified flow regime of water/SDBS mixture-gas flow expanded compared with that of water-gas.

  16. Comparative study of climate-change scenarios on groundwater recharge, southwestern Mississippi and southeastern Louisiana, USA (United States)

    Beigi, Ehsan; Tsai, Frank T.-C.


    A geographic information system (GIS)-based water-budget framework has been developed to study the climate-change impact on regional groundwater recharge, and it was applied to the Southern Hills aquifer system of southwestern Mississippi and southeastern Louisiana, USA. The framework links historical climate variables and future emission scenarios of climate models to a hydrologic model, HELP3, to quantify spatiotemporal potential recharge variations from 1950 to 2099. The framework includes parallel programming to divide a large amount of HELP3 simulations among multiple cores of a supercomputer, to expedite computation. The results show that a wide range of projected potential recharge for the Southern Hills aquifer system resulted from the divergent projections of precipitation, temperature and solar radiation using three scenarios (B1, A2 and A1FI) of the National Center for Atmospheric Research's Parallel Climate Model 1 (PCM) and the National Oceanic and Atmospheric Administration Geophysical Fluid Dynamics Lab's (GFDL) model. The PCM model projects recharge change ranging from -33.7 to +19.1 % for the 21st century. The GFDL model projects less recharge than the PCM, with recharge change ranging from -58.1 to +7.1 %. Potential recharge is likely to increase in 2010-2039, but likely to decrease in 2070-2099. Projected recharge is more sensitive to the changes in the projected precipitation than the projected solar radiation and temperature. Uncertainty analysis confirms that the uncertainty in projected precipitation yields more changes in the potential recharge than in the projected temperature for the study area.

  17. Artificial groundwater recharge zones mapping using remote sensing and GIS: a case study in Indian Punjab. (United States)

    Singh, Amanpreet; Panda, S N; Kumar, K S; Sharma, Chandra Shekhar


    Artificial groundwater recharge plays a vital role in sustainable management of groundwater resources. The present study was carried out to identify the artificial groundwater recharge zones in Bist Doab basin of Indian Punjab using remote sensing and geographical information system (GIS) for augmenting groundwater resources. The study area has been facing severe water scarcity due to intensive agriculture for the past few years. The thematic layers considered in the present study are: geomorphology (2004), geology (2004), land use/land cover (2008), drainage density, slope, soil texture (2000), aquifer transmissivity, and specific yield. Different themes and related features were assigned proper weights based on their relative contribution to groundwater recharge. Normalized weights were computed using the Saaty's analytic hierarchy process. Thematic layers were integrated in ArcGIS for delineation of artificial groundwater recharge zones. The recharge map thus obtained was divided into four zones (poor, moderate, good, and very good) based on their influence to groundwater recharge. Results indicate that 15, 18, 37, and 30 % of the study area falls under "poor," "moderate," "good," and "very good" groundwater recharge zones, respectively. The highest recharge potential area is located towards western and parts of middle region because of high infiltration rates caused due to the distribution of flood plains, alluvial plain, and agricultural land. The least effective recharge potential is in the eastern and middle parts of the study area due to low infiltration rate. The results of the study can be used to formulate an efficient groundwater management plan for sustainable utilization of limited groundwater resources.

  18. The Pattern Across the Continental United States of Evapotranspiration Variability Associated with Water Availability (United States)

    Koster, Randal D.; Salvucci, Guido D.; Rigden, Angela J.; Jung, Martin; Collatz, G. James; Schubert, Siegfried D.


    The spatial pattern across the continental United States of the interannual variance of warm season water-dependent evapotranspiration, a pattern of relevance to land-atmosphere feedback, cannot be measured directly. Alternative and indirect approaches to estimating the pattern, however, do exist, and given the uncertainty of each, we use several such approaches here. We first quantify the water dependent evapotranspiration variance pattern inherent in two derived evapotranspiration datasets available from the literature. We then search for the pattern in proxy geophysical variables (air temperature, stream flow, and NDVI) known to have strong ties to evapotranspiration. The variances inherent in all of the different (and mostly independent) data sources show some differences but are generally strongly consistent they all show a large variance signal down the center of the U.S., with lower variances toward the east and (for the most part) toward the west. The robustness of the pattern across the datasets suggests that it indeed represents the pattern operating in nature. Using Budykos hydroclimatic framework, we show that the pattern can largely be explained by the relative strength of water and energy controls on evapotranspiration across the continent.

  19. Source Water Flow Pathways In Forested, Mountain, Headwater Streams: A Link Between Sediment Movement Patterns And Stream Water Chemistry. (United States)

    Martin, S.; Conklin, M. H.; Liu, F.


    Three years of continuous and discrete sediment and water quality data, from four forested, mountain, headwater catchments in the Sierra Nevada, is used to identify water sources, determine the importance of sub-surface flow pathways, detect any changes in source waters due to seasonal variation or drought, and link flow pathways with observed patterns of in-channel sediment movement within the study watersheds. Patterns in stream chemistry and turbidity point to infiltration as the dominant flow pathway within these catchments. Data support a flow pathway conceptual model in which precipitation water infiltrates into the shallow or deeper subsurface, increasing the hydraulic head of the water table and pushing pre-event water into the stream ahead of event water. Study catchments contain perennial streams and are characterized by a Mediterranean climate with a distinct wet and dry season. Sites are located in the rain-snow transition zone with snow making up 40 to 60 percent of average annual precipitation. Barring human disturbances such as logging/grazing (compaction) or fire (hydrophobicity), catchment soils have high infiltration capacities. Springs and seeps maintain baseflow during the summer low-flow season, and shifting chemical signals within the streams indicate the increased importance of sub-surface water sources during drought years. End-member mixing analysis was conducted to identify possible water end members. Turbidity hysteresis patterns described by previous studies show in-channel sources are dominant for discharge events year round, and there is no difference in fine sediment delivery to streams with or without a soil protecting layer of snow on the land surface. The dominance of sub-surface water sources and evidence for infiltration flow fits with turbidity data, as little material is reaching the stream due to erosive overland flow. An understanding of flow pathways provides a foundation for sustainable land use management in forested

  20. Food consumption patterns and their effect on water requirement in China (United States)

    Liu, J.; Savenije, H. H. G.


    It is widely recognized that food consumption patterns significantly impact water requirements. The aim of this paper is to quantify how food consumption patterns influence water requirements in China. The findings show that per capita water requirement for food (CWRF) has increased from 255 m3 cap-1y-1 in 1961 to 860 m3 cap-1 y-1 in 2003, largely due to an increase in the consumption of animal products in recent decades. Although steadily increasing, the CWRF of China is still much lower than that of many developed countries. The total water requirement for food (TWRF) has been determined as 1127 km3 y-1 in 2003. Three scenarios are proposed to project future TWRF, representing low, medium, and high levels of modernization (S1, S2, and S3, respectively). Analysis of these three scenarios indicates that TWRF will likely continue to increase in the next three decades. An additional amount of water ranging between 407 and 515 km3 y-1 will be required in 2030 compared to the TWRF in 2003. This will undoubtedly put high pressure on China's already scarce water resources. We conclude that the effect of the food consumption patterns on China's water resources is substantial both in the recent past and in the near future. China will need to strengthen "green water" management and to take advantage of "virtual water" import to meet the additional TWRF.

  1. Soil-water dynamics and tree water uptake in the Sacramento Mountains of New Mexico (USA): a stable isotope study (United States)

    Gierke, Casey; Newton, B. Talon; Phillips, Fred M.


    In the southwestern United States, precipitation in the high mountains is a primary source of groundwater recharge. Precipitation patterns, soil properties and vegetation largely control the rate and timing of groundwater recharge. The interactions between climate, soil and mountain vegetation thus have important implications for the groundwater supply. This study took place in the Sacramento Mountains, which is the recharge area for multiple regional aquifers in southern New Mexico. The stable isotopes of oxygen and hydrogen were used to determine whether infiltration of precipitation is homogeneously distributed in the soil or whether it is partitioned among soil-water `compartments', from which trees extract water for transpiration as a function of the season. The results indicate that "immobile" or "slow" soil water, which is derived primarily from snowmelt, infiltrates soils in a relatively uniform fashion, filling small pores in the shallow soils. "Mobile" or "fast" soil water, which is mostly associated with summer thunderstorms, infiltrates very quickly through macropores and along preferential flow paths, evading evaporative loss. It was found that throughout the entire year, trees principally use immobile water derived from snowmelt mixed to differing degrees with seasonally available mobile-water sources. The replenishment of these different water pools in soils appears to depend on initial soil-water content, the manner in which the water was introduced to the soil (snowmelt versus intense thunderstorms), and the seasonal variability of the precipitation and evapotranspiration. These results have important implications for the effect of climate change on recharge mechanisms in the Sacramento Mountains.

  2. Estimation of Groundwater Recharge Using Tracers and Numerical Modeling in the North China Plain

    Directory of Open Access Journals (Sweden)

    Qinghua Wu


    Full Text Available Water resource shortage has been a serious problem since the 1980s in the North China Plain (NCP, resulting in plenty of environmental problems. Estimating the groundwater recharge rate accurately is vital for managing groundwater effectively. This study applied several methods, including chloride mass-balance, tracers (bromide and tritium and numerical modeling (Hydrus-1D, to estimate groundwater recharge at three representative sites of the NCP: Zhengding (ZD, Luancheng (LC and Hengshui (HS. The chloride concentration of the soil profile in the ZD site showed that the mean recharge was 3.84 mm/year with the residence time of 105 years for soil water transferring through the vadose area of 45.0 m in depth in the preferential flow model mainly. Considering the influence of preferential flow on the soil water movement in the field scale, the traditional methods (e.g., peak method of bromide and tritium tracers based on piston flow described in the literature could be unsuitable to estimate groundwater recharge in the LC and HS sites, especially in areas with low recharge rates. Therefore, multi-region and mass balance methods were applied in this study. The results of this investigation showed that the mean values of recharge were 124.3 and 18.0 mm/year in the LC and HS sites, respectively, in 2010. Owing to complexity and uncertainty on the surface resulting from the measuring of evapotranspiration, the upper boundary of 1.4 m (under the ground where most of the plant roots did not reach was chosen for the numerical modeling of Hydrus-1D, and the result showed that the mean recharge was 225 mm/year from 2003 to 2007, consistent with the result of tracers in the previous literature. The result also showed that the positive relation of groundwater recharge and the sum of irrigation and rainfall was presented in the spatial and temporal scale. Additionally, human activities promoted the recharge rate, and recharge rates increased with greater

  3. Quantifying depression-focused recharge in a seasonally frozen, semi-arid landscape (United States)

    Cey, Edwin; Noorduijn, Saskia; Mohammed, Aaron; Pavlovskii, Igor; Bentley, Laurence; Hayashi, Masaki


    Groundwater recharge in the northern prairie region is influenced by seasonal accumulation of snowmelt runoff in numerous closed topographic depressions (tens to 100's of meters in size) that dot the landscape. Estimating recharge is difficult due to the number and complexity of processes at play, including snow redistribution, runoff, infiltration, evapotranspiration, lateral water redistribution, and recharge, which take place on clay-rich, macroporous sediments that are seasonally frozen. A multi-faceted study, referred to as the Groundwater Recharge in the Prairies (GRIP) project, was undertaken on the Canadian prairies in order to better understand the key hydrologic processes and to generate reliable basin-scale estimates of groundwater recharge that are necessary for sustainable groundwater management. Detailed monitoring of hydrological fluxes across individual depression-midslope-upland complexes was undertaken at three field sites located in different ecoregions, yielding valuable insights into the hydrologic processes and feedbacks within these individual micro-catchments. This process understanding was incorporated into a relatively simple one-dimensional (1D) water budget model, to which a new upscaling scheme was applied to estimate recharge over a watershed or multiple watersheds. The 1D model links upland and depression processes for an individual micro-catchment, and then upscales to a larger model grid cell based on a categorization of depressions based on their surface area and density within the grid cell. This approach enables explicit incorporation of relevant recharge processes, thus producing realistic recharge estimates, while limiting computational demand. The model has been calibrated and tested against a long-term data set from one of the field sites. Results demonstrate complex relationships between upland-depression water transfers and catchment geometry, resulting in maximal groundwater recharge in catchments with intermediate ratios

  4. Classification of Thermal Patterns at Karst Springs and Cave Streams (United States)

    Luhmann, A.J.; Covington, M.D.; Peters, Albert J.; Alexander, S.C.; Anger, C.T.; Green, J.A.; Runkel, Anthony C.; Alexander, E.C.


    Thermal patterns of karst springs and cave streams provide potentially useful information concerning aquifer geometry and recharge. Temperature monitoring at 25 springs and cave streams in southeastern Minnesota has shown four distinct thermal patterns. These patterns can be divided into two types: those produced by flow paths with ineffective heat exchange, such as conduits, and those produced by flow paths with effective heat exchange, such as small fractures and pore space. Thermally ineffective patterns result when water flows through the aquifer before it can equilibrate to the rock temperature. Thermally ineffective patterns can be either event-scale, as produced by rainfall or snowmelt events, or seasonal scale, as produced by input from a perennial surface stream. Thermally effective patterns result when water equilibrates to rock temperature, and the patterns displayed depend on whether the aquifer temperature is changing over time. Shallow aquifers with seasonally varying temperatures display a phase-shifted seasonal signal, whereas deeper aquifers with constant temperatures display a stable temperature pattern. An individual aquifer may display more than one of these patterns. Since karst aquifers typically contain both thermally effective and ineffective routes, we argue that the thermal response is strongly influenced by recharge mode. ?? 2010 The Author(s). Journal compilation ?? 2010 National Ground Water Association.

  5. Parameterization and quantification of recharge in crystalline fractured bedrocks in Galicia-Costa (NW Spain

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    J. R. Raposo


    Full Text Available Quantifying groundwater recharge in crystalline rocks presents great difficulties due to the high heterogeneity of the underground medium (mainly, due to heterogeneity in fracture network, which determines hydraulic parameters of the bedrock like hydraulic conductivity or effective porosity. Traditionally these rocks have been considered to have very low permeability, and their groundwater resources have usually been neglected; however, they can be of local importance when the bedrock presents a net of well-developed fractures. The current European Water Framework Directive requires an efficient management of all groundwater resources; this begins with a proper knowledge of the aquifer and accurate recharge estimation. In this study, an assessment of groundwater resources in the Spanish hydrologic district of Galicia-Costa, dominated by granitic and metasedimentary rocks, was carried out. A water-balance modeling approach was used for estimating recharge rates in nine pilot catchments representatives of both geologic materials. These results were cross-validated with an independent technique, i.e. the chloride mass balance (CMB. A relation among groundwater recharge and annual precipitation according to two different logistic curves was found for both granites and metasedimentary rocks, thus allowing the parameterization of recharge by means of only a few hydrogeological parameters. Total groundwater resources in Galicia-Costa were estimated to be 4427 hm3 yr−1. An analysis of spatial and temporal variability of recharge was also carried out.

  6. Sensitivity of groundwater recharge using climatic analogues and HYDRUS-1D (United States)

    Leterme, B.; Mallants, D.; Jacques, D.


    The sensitivity of groundwater recharge to different climate conditions was simulated using the approach of climatic analogue stations, i.e. stations presently experiencing climatic conditions corresponding to a possible future climate state. The study was conducted in the context of a safety assessment of a future near-surface disposal facility for low and intermediate level short-lived radioactive waste in Belgium; this includes estimation of groundwater recharge for the next millennia. Groundwater recharge was simulated using the Richards based soil water balance model HYDRUS-1D and meteorological time series from analogue stations. This study used four analogue stations for a warmer subtropical climate with changes of average annual precipitation and potential evapotranspiration from -42% to +5% and from +8% to +82%, respectively, compared to the present-day climate. Resulting water balance calculations yielded a change in groundwater recharge ranging from a decrease of 72% to an increase of 3% for the four different analogue stations. The Gijon analogue station (Northern Spain), considered as the most representative for the near future climate state in the study area, shows an increase of 3% of groundwater recharge for a 5% increase of annual precipitation. Calculations for a colder (tundra) climate showed a change in groundwater recharge ranging from a decrease of 97% to an increase of 32% for four different analogue stations, with an annual precipitation change from -69% to -14% compared to the present-day climate.

  7. Analysis of vadose zone inhomogeneity toward distinguishing recharge rates: Solving the nonlinear interface problem with Newton method (United States)

    Steward, David R.


    Recharge from surface to groundwater is an important component of the hydrological cycle, yet its rate is difficult to quantify. Percolation through two-dimensional circular inhomogeneities in the vadose zone is studied where one soil type is embedded within a uniform background, and nonlinear interface conditions in the quasilinear formulation are solved using Newton's method with the Analytic Element Method. This numerical laboratory identifies detectable variations in pathline and pressure head distributions that manifest due to a shift in recharge rate through in a heterogeneous media. Pathlines either diverge about or converge through coarser and finer grained materials with inverse patterns forming across lower and upper elevations; however, pathline geometry is not significantly altered by recharge. Analysis of pressure head in lower regions near groundwater identifies a new phenomenon: its distribution is not significantly impacted by an inhomogeneity soil type, nor by its placement nor by recharge rate. Another revelation is that pressure head for coarser grained inhomogeneities in upper regions is completely controlled by geometry and conductivity contrasts; a shift in recharge generates a difference Δp that becomes an additive constant with the same value throughout this region. In contrast, shifts in recharge for finer grained inhomogeneities reveal patterns with abrupt variations across their interfaces. Consequently, measurements aimed at detecting shifts in recharge in a heterogeneous vadose zone by deciphering the corresponding patterns of change in pressure head should focus on finer grained inclusions well above a groundwater table.

  8. Simulation of the ground-water-flow system in the Kalamazoo County area, Michigan (United States)

    Luukkonen, Carol L.; Blumer, Stephen P.; Weaver, T.L.; Jean, Julie


    A ground-water-flow model was developed to investigate the ground-water resources of Kalamazoo County. Ground water is widely used as a source of water for drinking and industry in Kalamazoo County and the surrounding area. Additionally, lakes and streams are valued for their recreational and aesthetic uses. Stresses on the ground-water system, both natural and human-induced, have raised concerns about the long-term availability of ground water for people to use and for replenishment of lakes and streams. Potential changes in these stresses, including withdrawals and recharge, were simulated using a ground-water-flow model. Simulations included steady-state conditions (in which stresses remained constant and changes in storage were not included) and transient conditions (in which stresses changed in seasonal and monthly time scales and storage within the system was included). Steady-state simulations were used to investigate the long-term effects on water levels and streamflow of a reduction in recharge or an increase in pumping to projected 2010 withdrawal rates, withdrawal and application of water for irrigation, and a reduction in recharge in urban areas caused by impervious surfaces. Transient simulations were used to investigate changes in withdrawals to match seasonal and monthly patterns under various recharge conditions, and the potential effects of the use of water for irrigation over the summer months. With a reduction in recharge, simulated water levels declined over most of the model area in Kalamazoo County; with an increase in pumping, water levels declined primarily near pumping centers. Because withdrawals by wells intercept water that would have discharged possibly to a stream or lake, model simulations indicated that streamflow was reduced with increased withdrawals. With withdrawal and consumption of water for irrigation, simulated water levels declined. Assuming a reduction in recharge due to urbanization, water levels declined and flow to

  9. Effect of irrigation return flow on groundwater recharge in an overexploited aquifer in Bangladesh (United States)

    Touhidul Mustafa, Syed Md.; Shamsudduha, Mohammad; Huysmans, Marijke


    Irrigated agriculture has an important role in the food production to ensure food security of Bangladesh that is home to over 150 million people. However, overexploitation of groundwater for irrigation, particularly during the dry season, causes groundwater-level decline in areas where abstraction is high and surface geology inhibits direct recharge to underlying shallow aquifer. This is causing a number of potential adverse socio-economic, hydrogeological, and environmental problems in Bangladesh. Alluvial aquifers are primarily recharged during monsoon season from rainfall and surface sources. However, return flow from groundwater-fed irrigation can recharge during the dry months. Quantification of the effect of return flow from irrigation in the groundwater system is currently unclear but thought to be important to ensure sustainable management of the overexploited aquifer. The objective of the study is to investigate the effect of irrigation return flow on groundwater recharge in the north-western part of Bangladesh, also known as Barind Tract. A semi-physically based distributed water balance model (WetSpass-M) is used to simulate spatially distributed monthly groundwater recharge. Results show that, groundwater abstraction for irrigation in the study area has increased steadily over the last 29 years. During the monsoon season, local precipitation is the controlling factor of groundwater recharge; however, there is no trend in groundwater recharge during that period. During the dry season, however, irrigation return-flow plays a major role in recharging the aquifer in the irrigated area compared to local precipitation. Therefore, during the dry season, mean seasonal groundwater recharge has increased and almost doubled over the last 29 years as a result of increased abstraction for irrigation. The increase in groundwater recharge during dry season has however no significant effect in the improvement of groundwater levels. The relation between groundwater

  10. Arsenic release during managed aquifer recharge (MAR) (United States)

    Pichler, T.; Lazareva, O.; Druschel, G.


    The mobilization and addition of geogenic trace metals to groundwater is typically caused by anthropogenic perturbations of the physicochemical conditions in the aquifer. This can add dangerously high levels of toxins to groundwater, thus compromising its use as a source of drinking water. In several regions world-wide, aquifer storage and recovery (ASR), a form of managed aquifer recharge (MAR), faces the problem of arsenic release due to the injection of oxygenated storage water. To better understand this process we coupled geochemical reactive transport modeling to bench-scale leaching experiments to investigate and verify the mobilization of geogenic arsenic (As) under a range of redox conditions from an arsenic-rich pyrite bearing limestone aquifer in Central Florida. Modeling and experimental observations showed similar results and confirmed the following: (1) native groundwater and aquifer matrix, including pyrite, were in chemical equilibrium, thus preventing the release of As due to pyrite dissolution under ambient conditions; (2) mixing of oxygen-rich surface water with oxygen-depleted native groundwater changed the redox conditions and promoted the dissolution of pyrite, and (3) the behavior of As along a flow path was controlled by a complex series of interconnected reactions. This included the oxidative dissolution of pyrite and simultaneous sorption of As onto neo-formed hydrous ferric oxides (HFO), followed by the reductive dissolution of HFO and secondary release of adsorbed As under reducing conditions. Arsenic contamination of drinking water in these systems is thus controlled by the re-equilibration of the system to more reducing conditions rather than a purely oxidative process.

  11. Pattern of Water Use and Seed Yield under Terminal Drought in Chickpea Genotypes

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    Jiayin Pang


    Full Text Available Drought, particularly terminal drought, reduces the yield of chickpea (Cicer arietinum L.. Terminal drought tolerance and water use patterns were evaluated under controlled conditions in 10 genotypes of desi chickpea. Withholding water from early podding reduced vegetative growth, reproductive growth, seed yield, and water use efficiency for seed yield in all genotypes. The genotype Neelam, which produced the highest seed yield when water was withheld, used the least water when well-watered; however, its aboveground biomass at maturity did not differ significantly from six of the nine other genotypes. Indeed, the water-stressed Neelam had the lowest daily transpiration rate during the early stages of water stress and the highest during the later stages, thereby maintaining the highest soil water content in the first 16 days after water was withheld, which enabled higher pod production, lower pod abortion, and better seed filling. Genotypes differed in the threshold value of the fraction of transpirable soil water when flowering and seed set ceased in the water-stress treatment. We conclude that a conservative water use strategy benefits seed yield of chickpea exposed to water shortage during early podding.

  12. Changes in projected spatial and seasonal groundwater recharge in the upper Colorado River Basin (United States)

    Tillman, Fred; Gangopadhyay, Subhrendu; Pruitt, Tom


    The Colorado River is an important source of water in the western United States, supplying the needs of more than 38 million people in the United States and Mexico. Groundwater discharge to streams has been shown to be a critical component of streamflow in the Upper Colorado River Basin (UCRB), particularly during low-flow periods. Understanding impacts on groundwater in the basin from projected climate change will assist water managers in the region in planning for potential changes in the river and groundwater system. A previous study on changes in basin-wide groundwater recharge in the UCRB under projected climate change found substantial increases in temperature, moderate increases in precipitation, and mostly periods of stable or slight increases in simulated groundwater recharge through 2099. This study quantifies projected spatial and seasonal changes in groundwater recharge within the UCRB from recent historical (1950 to 2015) through future (2016 to 2099) time periods, using a distributed-parameter groundwater recharge model with downscaled climate data from 97 Coupled Model Intercomparison Project Phase 5 (CMIP5) climate projections. Simulation results indicate that projected increases in basin-wide recharge of up to 15% are not distributed uniformly within the basin or throughout the year. Northernmost subregions within the UCRB are projected an increase in groundwater recharge, while recharge in other mainly southern subregions will decline. Seasonal changes in recharge also are projected within the UCRB, with decreases of 50% or more in summer months and increases of 50% or more in winter months for all subregions, and increases of 10% or more in spring months for many subregions.

  13. The Studies of Regional Water Circulation Patterns in the Yerqiang River Basin

    Institute of Scientific and Technical Information of China (English)

    REN Jiaguo; WU Qianqian; ZHENG Xilai; XU Mo


    Based on the characteristic of ‘one river one oasis' in the arid areas, the Yerqiang River Basin, which is the largest irrigated area of Xinjiang, is taken as an example in this paper, and the regional water circulation pattern is investigated through the analysis of 60 groups of isotope data in the basin. From the phreatic evaporation data analysis of different soils, we study the law of phreatic evaporation, complete the research of the main consumption path of the groundwater,and improve the assessment precision of water resources. The transformation mount of regional water resources are predicted by calculation, which provides a scientific basis for water resources assessment and allocation in arid regions, and offers a new method for the study of regional water circulation patterns.

  14. Enhancement of Water Evaporation on Solid Surfaces with Nanoscale Hydrophobic-Hydrophilic Patterns. (United States)

    Wan, Rongzheng; Wang, Chunlei; Lei, Xiaoling; Zhou, Guoquan; Fang, Haiping


    Using molecular dynamics simulations, we show that the evaporation of nanoscale water on hydrophobic-hydrophilic patterned surfaces is unexpectedly faster than that on any surfaces with uniform wettability. The key to this phenomenon is that, on the patterned surface, the evaporation rate from the hydrophilic region only slightly decreases due to the correspondingly increased water thickness; meanwhile, a considerable number of water molecules evaporate from the hydrophobic region despite the lack of water film. Most of the evaporated water from the hydrophobic region originates from the hydrophilic region by diffusing across the contact lines. Further analysis shows that the evaporation rate from the hydrophobic region is approximately proportional to the total length of the contact lines.

  15. Areas Contributing Recharge to Wells in the Tafuna-Leone Plain, Tutuila, American Samoa (United States)

    Izuka, Scot K.; Perreault, Jeff A.; Presley, Todd K.


    To address the concerns about the potential for contamination of drinking-water wells in the Tafuna-Leone Plain, Tutuila, American Samoa, a numerical ground-water flow model was developed and used to delineate areas contributing recharge to the wells (ACRWs). Surveys and analyses were conducted to obtain or compile certain essential hydrogeologic information needed for the model, such as groundwater production statistics, ground-water levels under current production, and an assessment of the distribution of groundwater recharge. The ground-water surveys indicate that total production from all wells in the Tafuna-Leone Plain between 1985 and 2005 averaged 6.1 Mgal/d and showed a gradual increase. A synoptic survey indicates that current water levels in the Tafuna-Leone Plain are highest near its inland boundary, decrease toward the coast, and are slightly depressed in high-production well fields. Ground-water levels showed little effect from the increased production because hydraulic conductivites are high and withdrawal is small relative to recharge. Analysis of ground-water recharge using a soil water-budget analysis indicates that the Tafuna-Leone Plain and adjacent areas receive about 280 Mgal/d of water from rainfall, of which 24 percent runs off to the ocean, 26 percent is removed by evapotranspiration, and 50 percent goes to ground-water recharge. Ground-water recharge per unit area is generally higher at the mountain crests than at the coast, but the highest recharge per unit area is in the mountain-front recharge zone at the juncture between the Tafuna-Leone Plain and the adjacent mountains. Surface water from the mountains also contributes to ground-water recharge in the eastern Tafuna-Leone Plain, in a process analogous to mountain-front recharge described in arid areas. Analysis of stream-gage data indicates that in the mountains of Tutuila, ground water discharges and contributes substantially to the total flow of the streams. In contrast, multiple

  16. Pilot Test of Advanced Treatments Combination of Wastewater for Groundwater Recharge

    Institute of Scientific and Technical Information of China (English)

    成徐洲; 杨磊; 吴天宝; 甘一苹; 胡俊


    To solve the water shortage problem, an artificial groundwater recharge system will be constructed in Beijing for wastewater reuse as a demonstration and training center. Design and operating experience for the demonstration plant was gained through pilot tests of advanced treatment technologies with soil infiltration of well treated secondary effluent. The test results showed that the selected treatment technology meets the recommended water quality criteria for groundwater recharge and the gas chromatography-mass spectrometer (GC/MS) analysis results showed significantly improved water quality.

  17. A Tropical Ocean Recharge Mechanism for Climate Variability. Part II: A Unified Theory for Decadal and ENSO Modes. (United States)

    Wang, Xiaochun; Jin, Fei-Fei; Wang, Yuqing


    Decadal to interdecadal timescale variability in the Pacific region, commonly referred to as the Pacific decadal oscillation (PDO), is studied in this research using analytical and numerical models. A coupled analytical model is formulated to analyze the physical mechanism of both the PDO and ENSO. It has the equatorial β-plane dynamics of a reduced-gravity model coupled with the wind stress of fixed spatial patterns. The amplitude of the latter is proportional to the sea surface temperature (SST) anomaly in the eastern equatorial Pacific. The SST anomaly is governed by a simple thermal dynamic equation used for ENSO modeling. It is found that when a warm SST is coupled with cyclonic wind stress patterns in the eastern subtropical Pacific, an oscillation with a timescale of around 10 15 yr could be generated. In contrast, when a warm SST is coupled with only a westerly wind stress in the central equatorial Pacific, an ENSO-like oscillation could be generated with a timescale of around 3 5 yr. Thus the present research is potentially relevant to aspects of the PDO and the mechanism of the PDO may be understood as a weakly coupled decadal recharge oscillator similar to the recharge oscillator dynamics of ENSO. The sensitivity of these two kinds of coupled modes to different parameters is tested. Numerical integrations with the reduced-gravity shallow-water model in a rectangular basin and a similar coupled framework confirm the results of the analytical model.

  18. Analysing water use patterns for demand management: the case of the city of Masvingo, Zimbabwe (United States)

    Dube, Emmanuel; van der Zaag, Pieter

    Water use in urban centres is dynamic, fluctuates, differs between high and low-income users, and tends to increase over time. Supply infrastructure can often hardly keep pace with increased water consumption. Given (a) the high cost of infrastructure development, (b) the recent emphasis on demand management, and (c) the social obligation to provide water services to the poor, urban water providers are faced with an important choice: whether to go the demand management route, or to continue constructing new infrastructure. This paper sheds light on some of the possibilities and constraints of both choices by providing a case study of the city of Masvingo in Zimbabwe. The paper analyses water use patterns in this city with a population of 70,000, located in a drought prone region of average rainfall of 600 mm/a. Water consumption has reached the limits of the water supply capacity. The paper first looks at the long-term water use pattern of the city as a whole and the factors that have caused the observed pattern using multiple linear regression. The paper then analyses the patterns of water use of rich and poor households, and attempts to assess the (im)possibilities of influencing these by means of an appropriate tariff structure. In projecting future demand, the paper then considers a number of interventions that could influence demand, which include leakage control, pressure management, awareness campaigns, free technical advice to water users, as well as a new tariff structure. It also discusses when new supply infrastructure should be available, depending on the various demand management measures taken.

  19. Local Circulation Maintains the Coexistence of Lake-dune Pattern in the Badain Jaran Desert (United States)

    Zhang, Kecun; Cai, Diwen; Ao, Yinhuan; An, Zhishan; Guo, Zichen


    Previous studies proposed various hypotheses to the formation of the mega-dunes and water recharge of the lakes in the Badain Jaran Desert but left the coexistence of lake-dune pattern unsolved. This research found that the local circulation, generated from the differences of thermodynamic properties and the unique landscape settings between lakes and mega-dunes, can be applied to interpret the pattern.

  20. Use of Ground-water Temperature Patterns to Determine the Hydraulic Conductance of the Streambed Along the M