Modeling the Thickness of Perennial Ice Covers on Stratified Lakes of the Taylor Valley, Antarctica

Science.gov (United States)

Obryk, M. K.; Doran, P. T.; Hicks, J. A.; McKay, C. P.; Priscu, J. C.

2016-01-01

A one-dimensional ice cover model was developed to predict and constrain drivers of long term ice thickness trends in chemically stratified lakes of Taylor Valley, Antarctica. The model is driven by surface radiative heat fluxes and heat fluxes from the underlying water column. The model successfully reproduced 16 years (between 1996 and 2012) of ice thickness changes for west lobe of Lake Bonney (average ice thickness = 3.53 m; RMSE = 0.09 m, n = 118) and Lake Fryxell (average ice thickness = 4.22 m; RMSE = 0.21 m, n = 128). Long-term ice thickness trends require coupling with the thermal structure of the water column. The heat stored within the temperature maximum of lakes exceeding a liquid water column depth of 20 m can either impede or facilitate ice thickness change depending on the predominant climatic trend (temperature cooling or warming). As such, shallow (< 20 m deep water columns) perennially ice-covered lakes without deep temperature maxima are more sensitive indicators of climate change. The long-term ice thickness trends are a result of surface energy flux and heat flux from the deep temperature maximum in the water column, the latter of which results from absorbed solar radiation.

Groundwater quality in the Bear Valley and Lake Arrowhead Watershed, California

Science.gov (United States)

Mathany, Timothy; Burton, Carmen; Fram, Miranda S.

2017-06-20

Groundwater provides more than 40 percent of California’s drinking water. To protect this vital resource, the State of California created the Groundwater Ambient Monitoring and Assessment (GAMA) Program. The Priority Basin Project of the GAMA Program provides a comprehensive assessment of the State’s groundwater quality and increases public access to groundwater-quality information. The Bear Valley and Lake Arrowhead Watershed study areas in southern California compose one of the study units being evaluated.

Geochemistry of waters in the Valley of Ten Thousand Smokes region, Alaska

Science.gov (United States)

Keith, T.E.C.; Thompson, J.M.; Hutchinson, R.A.; White, L.D.

1992-01-01

Meteoric waters from cold springs and streams outside of the 1912 eruptive deposits filling the Valley of Ten Thousand Smokes (VTTS) and in the upper parts of the two major rivers draining the 1912 deposits have similar chemical trends. Thermal springs issue in the mid-valley area along a 300-m lateral section of ash-flow tuff, and range in temperature from 21 to 29.8??C in early summer and from 15 to 17??C in mid-summer. Concentrations of major and minor chemical constituents in the thermal waters are nearly identical regardless of temperature. Waters in the downvalley parts of the rivers draining the 1912 deposits are mainly mixtures of cold meteoric waters and thermal waters of which the mid-valley thermal spring waters are representative. The weathering reactions of cold waters with the 1912 deposits appear to have stabilized and add only subordinate amounts of chemical constituents to the rivers relative to those contributed by the thermal waters. Isotopic data indicate that the mid-valley thermal spring waters are meteoric, but data is inconclusive regarding the heat source. The thermal waters could be either from a shallow part of a hydrothermal system beneath the 1912 vent region or from an incompletely cooled, welded tuff lens deep in the 1912 ash-flow sheet of the upper River Lethe area. Bicarbonate-sulfate waters resulting from interaction of near-surface waters and the cooling 1953-1968 southwest Trident plug issue from thermal springs south of Katmai Pass and near Mageik Creek, although the Mageik Creek spring waters are from a well-established, more deeply circulating hydrothermal system. Katmai caldera lake waters are a result of acid gases from vigorous drowned fumaroles dissolving in lake waters composed of snowmelt and precipitation. ?? 1992.

Water resources of Parowan Valley, Iron County, Utah

Science.gov (United States)

Marston, Thomas M.

2017-08-29

. Groundwater flows from the high-altitude recharge areas downward toward the basin-fill aquifer in Parowan Valley. Almost all groundwater discharge occurs as withdrawals from irrigation wells in the valley with a small amount of discharge from phreatophytic evapotranspiration. Subsurface groundwater discharge to Cedar Valley is likely minimal. Withdrawals from wells during 2013 were about 32,000 acre-ft. The estimated withdrawals from wells from 1994 to 2013 have ranged from 22,000 to 39,000 acre-ft per year. Declining water levels are an indication of the estimated average annual decrease in groundwater storage of 15,000 acre-ft from 1994 to 2013.Groundwater and surface-water samples were collected from 46 sites in Parowan Valley and Cedar Valley near the town of Enoch during June 2013. Groundwater samples from 34 wells were submitted for geochemical analysis. The total dissolved-solids concentration in water from these wells ranged from 142 to 886 milligrams per liter. Results of stable isotope analysis of oxygen and deuterium from groundwater and surface-water samples indicate that most of the groundwater in Parowan Valley and in Cedar Valley near Enoch is similar in isotopic composition to water from mountain streams, which reflects meteoric water recharged in high-altitude areas east of the valley. In addition, results of stable isotope analysis of a subset of samples from wells located near Little Salt Lake may indicate recharge of precipitation that occurred during cooler climatic conditions of the Pleistocene Epoch.

Water Budgets of the Walker River Basin and Walker Lake, California and Nevada

Science.gov (United States)

Lopes, Thomas J.; Allander, Kip K.

2009-01-01

The Walker River is the main source of inflow to Walker Lake, a closed-basin lake in west-central Nevada. The only outflow from Walker Lake is evaporation from the lake surface. Between 1882 and 2008, upstream agricultural diversions resulted in a lake-level decline of more than 150 feet and storage loss of 7,400,000 acre-feet. Evaporative concentration increased dissolved solids from 2,500 to 17,000 milligrams per liter. The increase in salinity threatens the survival of the Lahontan cutthroat trout, a native species listed as threatened under the Endangered Species Act. This report describes streamflow in the Walker River basin and an updated water budget of Walker Lake with emphasis on the lower Walker River basin downstream from Wabuska, Nevada. Water budgets are based on average annual flows for a 30-year period (1971-2000). Total surface-water inflow to the upper Walker River basin upstream from Wabuska was estimated to be 387,000 acre-feet per year (acre-ft/yr). About 223,000 acre-ft/yr (58 percent) is from the West Fork of the Walker River; 145,000 acre-ft/yr (37 percent) is from the East Fork of the Walker River; 17,000 acre-ft/yr (4 percent) is from the Sweetwater Range; and 2,000 acre-ft/yr (less than 1 percent) is from the Bodie Mountains, Pine Grove Hills, and western Wassuk Range. Outflow from the upper Walker River basin is 138,000 acre-ft/yr at Wabuska. About 249,000 acre-ft/yr (64 percent) of inflow is diverted for irrigation, transpired by riparian vegetation, evaporates from lakes and reservoirs, and recharges alluvial aquifers. Stream losses in Antelope, Smith, and Bridgeport Valleys are due to evaporation from reservoirs and agricultural diversions with negligible stream infiltration or riparian evapotranspiration. Diversion rates in Antelope and Smith Valleys were estimated to be 3.0 feet per year (ft/yr) in each valley. Irrigated fields receive an additional 0.8 ft of precipitation, groundwater pumpage, or both for a total applied-water rate

Limnology of the Green Lakes Valley: Phytoplankton ecology and dissolved organic matter biogeochemistry at a long-term ecological research site

Science.gov (United States)

Miller, Matthew P.; McKnight, Diane M.

2015-01-01

Background: Surface waters are the lowest points in the landscape, and therefore serve as excellent integrators and indicators of changes taking place in the surrounding terrestrial and atmospheric environment.Aims: Here we synthesise the findings of limnological studies conducted during the past 15 years in streams and lakes in the Green Lakes Valley, which is part of the Niwot Ridge Long-term Ecological Research (LTER) Site.Methods: The importance of these studies is discussed in the context of aquatic ecosystems as indicators, integrators, and regulators of environmental change. Specifically, investigations into climatic, hydrologic, and nutrient controls on present-day phytoplankton, and historical diatom, community composition in the alpine lake, Green Lake 4, are reviewed. In addition, studies of spatial and temporal patterns in dissolved organic matter (DOM) biogeochemistry and reactive transport modelling that have taken place in the Green Lakes Valley are highlighted.Results and conclusions: The findings of these studies identify specific shifts in algal community composition and DOM biogeochemistry that are indicative of changing environmental conditions and provide a framework for detecting future environmental change in the Green Lakes Valley and in other alpine watersheds. Moreover, the studies summarised here demonstrate the importance of long-term monitoring programmes such as the LTER programme.

Factors affecting fish biodiversity in floodplain lakes of the Mississippi Alluvial Valley

Science.gov (United States)

Miranda, Leandro E.; Dembkowski, Daniel J.

2012-01-01

River-floodplain ecosystems offer some of the most diverse and dynamic environments in the world. Accordingly, floodplain habitats harbor diverse fish assemblages. Fish biodiversity in floodplain lakes may be influenced by multiple variables operating on disparate scales, and these variables may exhibit a hierarchical organization depending on whether one variable governs another. In this study, we examined the interaction between primary variables descriptive of floodplain lake large-scale features, suites of secondary variables descriptive of water quality and primary productivity, and a set of tertiary variables descriptive of fish biodiversity across a range of floodplain lakes in the Mississippi Alluvial Valley of Mississippi and Arkansas (USA). Lakes varied considerably in their representation of primary, secondary, and tertiary variables. Multivariate direct gradient analyses indicated that lake maximum depth and the percentage of agricultural land surrounding a lake were the most important factors controlling variation in suites of secondary and tertiary variables, followed to a lesser extent by lake surface area. Fish biodiversity was generally greatest in large, deep lakes with lower proportions of watershed agricultural land. Our results may help foster a holistic approach to floodplain lake management and suggest the framework for a feedback model wherein primary variables can be manipulated for conservation and restoration purposes and secondary and tertiary variables can be used to monitor the success of such efforts.

Late Pleistocene Hansel Valley basaltic ash, northern Lake Bonneville, Utah, USA

Science.gov (United States)

Miller, D.M.; Oviatt, Charles G.; Nash, B.P.

2008-01-01

The Hansel Valley ash bed lies within 5 cm of the base of deposits of Lake Bonneville (???28 ka) in the vicinity of Great Salt Lake and provides a useful stratigraphic marker for this area of the lake basin. However, it has not been matched to an eruptive edifice, presumably because such an edifice was eroded by waves of Lake Bonneville. We present data for the chemical composition of the tephra and for possible matching lavas and tephras of the region, as well as grain size data for the tephra in an attempt to identify the location of the eruption. Matches with other tephras are negative, but lavas near the coarsest ash deposits match well with the distinctive high values of TiO2 and P2O5 of the ash. Neither chemistry nor grain size data points uniquely to a source area, but an area near the northwest shore of Great Salt Lake and within Curlew Valley is most likely. The Hansel Valley ash is an example of an ash that has no direct numerical date from proximal deposits, despite considerable study, yet nonetheless is useful for stratigraphic studies by virtue of its known stratigraphic position and approximate age. Basaltic tephras commonly are not as widespread as their rhyolitic counterparts, and in some cases apparently are produced by eruptive sources that are short lived and whose edifices are not persistent. ?? 2007 Elsevier Ltd and INQUA.

Preliminary appraisal of ground water in and near the ancestral Missouri River Valley, northeastern Montana

Science.gov (United States)

Levings, G.W.

1986-01-01

A preliminary appraisal was conducted in and near the ancestral Missouri River valley in northeastern Montana to describe the groundwater resources and to establish a data base for the area. The data base then could be used for future evaluation of possible changes in water levels or water quality. In this area, consolidated aquifers are the Upper Cretaceous Fox Hills-lower Hell Creek aquifer and the overlying Paleocene Fort Union Formation. Unconsolidated aquifers are Pleistocene terrace gravel and glacial deposits and Holocene alluvial deposits. Aquifers are recharged by precipitation, infiltration of streamflow, and possibly leakage from lakes and potholes. Groundwater moves from topographically higher areas to the ancestral valley, then along the ancestral valley to the southwest. Water is discharged from aquifers by evapotranspiration, springs and seeps, movement directly into streams and lakes, and from pumping wells. Average well yields are greatest for irrigation wells completed in outwash gravel (886 gallons/min). Eighteen wells were completed in various aquifers to monitor potential long-term changes in water levels and water quality. Measured water levels declined about 2 ft. or less during the study (1982-85). Chemical analysis of groundwater samples indicated that concentrations of some dissolved constituents exceeded U.S. Environmental Protection Agency standards for drinking water. (USGS)

Integrated hazard assessment of Cirenmaco glacial lake in Zhangzangbo valley, Central Himalayas

Science.gov (United States)

Wang, Weicai; Gao, Yang; Iribarren Anacona, Pablo; Lei, Yanbin; Xiang, Yang; Zhang, Guoqing; Li, Shenghai; Lu, Anxin

2018-04-01

Glacial lake outburst floods (GLOFs) have recently become one of the primary natural hazards in the Himalayas. There is therefore an urgent need to assess GLOF hazards in the region. Cirenmaco, a moraine-dammed lake located in the upstream portion of Zhangzangbo valley, Central Himalayas, has received public attention after its damaging 1981 outburst flood. Here, by combining remote sensing methods, bathymetric survey and 2D hydraulic modeling, we assessed the hazard posed by Cirenmaco in its current status. Inter-annual variation of Cirenmaco lake area indicates a rapid lake expansion from 0.10 ± 0.08 km2 in 1988 to 0.39 ± 0.04 km2 in 2013. Bathymetric survey shows the maximum water depth of the lake in 2012 was 115 ± 2 m and the lake volume was calculated to be 1.8 × 107 m3. Field geomorphic analysis shows that Cirenmaco glacial lake is prone to GLOFs as mass movements and ice and snow avalanches can impact the lake and the melting of the dead ice in the moraine can lower the dam level. HEC-RAS 2D model was then used to simulate moraine dam failure of the Cirenmaco and assess GLOF impacts downstream. Reconstruction of Cirenmaco 1981 GLOF shows that HEC-RAS can produce reasonable flood extent and water depth, thus demonstrate its ability to effectively model complex GLOFs. GLOF modeling results presented can be used as a basis for the implementation of disaster prevention and mitigation measures. As a case study, this work shows how we can integrate different methods to GLOF hazard assessment.

Hydrological Controls on Ecosystem Dynamics in Lake Fryxell, Antarctica.

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Radu Herbei

Full Text Available The McMurdo Dry Valleys constitute the largest ice free area of Antarctica. The area is a polar desert with an annual precipitation of ∼ 3 cm water equivalent, but contains several lakes fed by glacial melt water streams that flow from four to twelve weeks of the year. Over the past ∼20 years, data have been collected on the lakes located in Taylor Valley, Antarctica as part of the McMurdo Dry Valley Long-Term Ecological Research program (MCM-LTER. This work aims to understand the impact of climate variations on the biological processes in all the ecosystem types within Taylor Valley, including the lakes. These lakes are stratified, closed-basin systems and are perennially covered with ice. Each lake contains a variety of planktonic and benthic algae that require nutrients for photosynthesis and growth. The work presented here focuses on Lake Fryxell, one of the three main lakes of Taylor Valley; it is fed by thirteen melt-water streams. We use a functional regression approach to link the physical, chemical, and biological processes within the stream-lake system to evaluate the input of water and nutrients on the biological processes in the lakes. The technique has been shown previously to provide important insights into these Antarctic lacustrine systems where data acquisition is not temporally coherent. We use data on primary production (PPR and chlorophyll-A (CHLfrom Lake Fryxell as well as discharge observations from two streams flowing into the lake. Our findings show an association between both PPR, CHL and stream input.

Ground-water flow and quality, and geochemical processes, in Indian Wells Valley, Kern, Inyo, and San Bernardino counties, California, 1987-88

Science.gov (United States)

Berenbrock, Charles; Schroeder, R.A.

1994-01-01

An existing water-quality data base for the 300- square-mile Indian Wells Valley was updated by means of chemical and isotopic analysis of ground water. The wide range in measured concentrations of major ions and of minor constituents such as fluoride, borate, nitrate, manganese, and iron is attributed to geochemical reactions within lacustrine deposits of the valley floor. These reactions include sulfate reduction accompanied by generation of alkalinity, precipitation of carbonates, exchange of aqueous alkaline-earth ions for sodium on clays, and dissolution of evaporite minerals. Differences in timing and location of recharge, which originates primarily in the Sierra Nevada to the west, and evapotranspiration from a shallow water table on the valley floor result in a wide range in ratios of stable hydrogen and oxygen isotopes. As ground water moves from alluvium into lustrine deposits of the ancestral China Lake, dissolved-solids concen- trations increase from about 200 to more than 1,000 milligrams per liter; further large increases to several thousand milligrams per liter occur beneath the China Lake playa. Historical data show an increase during the past 20 years in dissolved- solids concentration in several wells in the principal pumping areas at Ridgecrest and between Ridgecrest and Inyokern. The increase apparently is caused by induced flow of saline ground water from nearby China, Mirror, and Satellite Lakes. A simplified advective-transport model calculates ground-water travel times between parts of the valley of at least several thousand years, indi- cating the presence of old ground water. A local ground-water line and an evaporation line estimated using isotopic data from the China Lake area inter- sect at a delta-deuterium value of about -125 permil. This indicates that late Pleistocene recharge was 15 to 35 permil more negative than current recharge.

Evaporation estimation of rift valley lakes: comparison of models.

Science.gov (United States)

Melesse, Assefa M; Abtew, Wossenu; Dessalegne, Tibebe

2009-01-01

Evapotranspiration (ET) accounts for a substantial amount of the water flux in the arid and semi-arid regions of the World. Accurate estimation of ET has been a challenge for hydrologists, mainly because of the spatiotemporal variability of the environmental and physical parameters governing the latent heat flux. In addition, most available ET models depend on intensive meteorological information for ET estimation. Such data are not available at the desired spatial and temporal scales in less developed and remote parts of the world. This limitation has necessitated the development of simple models that are less data intensive and provide ET estimates with acceptable level of accuracy. Remote sensing approach can also be applied to large areas where meteorological data are not available and field scale data collection is costly, time consuming and difficult. In areas like the Rift Valley regions of Ethiopia, the applicability of the Simple Method (Abtew Method) of lake evaporation estimation and surface energy balance approach using remote sensing was studied. The Simple Method and a remote sensing-based lake evaporation estimates were compared to the Penman, Energy balance, Pan, Radiation and Complementary Relationship Lake Evaporation (CRLE) methods applied in the region. Results indicate a good correspondence of the models outputs to that of the above methods. Comparison of the 1986 and 2000 monthly lake ET from the Landsat images to the Simple and Penman Methods show that the remote sensing and surface energy balance approach is promising for large scale applications to understand the spatial variation of the latent heat flux.

Evaporation Estimation of Rift Valley Lakes: Comparison of Models

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Tibebe Dessalegne

2009-12-01

Full Text Available Evapotranspiration (ET accounts for a substantial amount of the water flux in the arid and semi-arid regions of the World. Accurate estimation of ET has been a challenge for hydrologists, mainly because of the spatiotemporal variability of the environmental and physical parameters governing the latent heat flux. In addition, most available ET models depend on intensive meteorological information for ET estimation. Such data are not available at the desired spatial and temporal scales in less developed and remote parts of the world. This limitation has necessitated the development of simple models that are less data intensive and provide ET estimates with acceptable level of accuracy. Remote sensing approach can also be applied to large areas where meteorological data are not available and field scale data collection is costly, time consuming and difficult. In areas like the Rift Valley regions of Ethiopia, the applicability of the Simple Method (Abtew Method of lake evaporation estimation and surface energy balance approach using remote sensing was studied. The Simple Method and a remote sensing-based lake evaporation estimates were compared to the Penman, Energy balance, Pan, Radiation and Complementary Relationship Lake Evaporation (CRLE methods applied in the region. Results indicate a good correspondence of the models outputs to that of the above methods. Comparison of the 1986 and 2000 monthly lake ET from the Landsat images to the Simple and Penman Methods show that the remote sensing and surface energy balance approach is promising for large scale applications to understand the spatial variation of the latent heat flux.

Hierarchy in factors affecting fish biodiversity in floodplain lakes of the Mississippi Alluvial Valley

Science.gov (United States)

Dembkowski, D.J.; Miranda, L.E.

2012-01-01

River-floodplain ecosystems offer some of the most diverse and dynamic environments in the world. Accordingly, floodplain habitats harbor diverse fish assemblages. Fish biodiversity in floodplain lakes may be influenced by multiple variables operating on disparate scales, and these variables may exhibit a hierarchical organization depending on whether one variable governs another. In this study, we examined the interaction between primary variables descriptive of floodplain lake large-scale features, suites of secondary variables descriptive of water quality and primary productivity, and a set of tertiary variables descriptive of fish biodiversity across a range of floodplain lakes in the Mississippi Alluvial Valley of Mississippi and Arkansas (USA). Lakes varied considerably in their representation of primary, secondary, and tertiary variables. Multivariate direct gradient analyses indicated that lake maximum depth and the percentage of agricultural land surrounding a lake were the most important factors controlling variation in suites of secondary and tertiary variables, followed to a lesser extent by lake surface area. Fish biodiversity was generally greatest in large, deep lakes with lower proportions of watershed agricultural land. Our results may help foster a holistic approach to floodplain lake management and suggest the framework for a feedback model wherein primary variables can be manipulated for conservation and restoration purposes and secondary and tertiary variables can be used to monitor the success of such efforts. ?? 2011 Springer Science+Business Media B.V.

Ground water in Dale Valley, New York

Science.gov (United States)

Randall, Allan D.

1979-01-01

Dale Valley is a broad valley segment, enlarged by glacial erosion, at the headwaters of Little Tonawanda Creek near Warsaw , New York. A thin, shallow alluvial aquifer immediately underlies the valley floor but is little used. A deeper gravel aquifer, buried beneath many feet of lake deposits, is tapped by several industrial wells. A finite-difference digital model treated the deep aquifer as two-dimensional with recharge and discharge through a confining layer. It was calibrated by simulating (1) natural conditions, (2) an 18-day aquifer test, and (3) 91 days of well-field operation. Streamflow records and model simulations suggest that in moderately wet years such as 1974, a demand of 750 gallons per minute could be met by withdrawal from the creek and from the aquifer without excessive drawdown at production wells or existing domestic wells. With reasonable but unverified model adjustments to simulate an unusually dry year, the model predicts that a demand of 600 gallons per minute could be met from the same sources. Water high in chloride has migrated from bedrock into parts of the deep aquifer. Industrial pumpage, faults in the bedrock, and the natural flow system may be responsible. (Woodard-USGS)

Spatial relationships of the Preajba Valley Lakes evolution reflected on cartographic documents

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Marga AVRAM

2015-12-01

Full Text Available The Preajba-Facai lacustrine system is located in the southern part of Craiova municipality and it is distinguished by a high level of originality conferred by both its hydro-geomorphological and biological features. The construction of this series of lakes along the Preajba river began during the Communist times (in the 1970s with the declared aim of serving as a recreational space for the inhabitants of this municipality. The river springs near Cârcea locality at an altitude of 192 metres and it flows into Craiova channel after 9.6 km, with a source-mouth level difference of 121.1 metres. Chronologically, the number of lakes situated along the Preajba river may vary, according to the analysed cartographic document, from 3 lakes (Military Topographic Maps to 11 lakes (Topographic Map, 1:25,000. With the development of the area covered by water, the human pressure has increased as a consequence of the intensive development of the surrounding area. This phenomenon gradually led to an involution of the lake surface (25.34 ha in 2014, Google Earth PRO. The aim of this research is to highlight the relational dynamic appearance-evolution-involution suffered by the lakes situated along the Preajba Valley, in correlation with the processes that occurred at the level of the constructed surface and in terms of respecting the status of this protected area of aqua-faunistic interest (The Lacustrine System of Preajba-Facai.

Use of ground-water reservoirs for storage of surface water in the San Joaquin Valley, California

Science.gov (United States)

Davis, G.H.; Lofgren, B.E.; Mack, Seymour

1964-01-01

The San Joaquin Valley includes roughly the southern two-thirds of the Central Valley of California, extending 250 miles from Stockton on the north to Grapevine at the foot of the Tehachapi Mountains. The valley floor ranges in width from 25 miles near Bakersfield to about 55 miles near Visalia; it has a surface area of about 10,000 square miles. More than one-quarter of all the ground water pumped for irrigation in the United States is used in this highly productive valley. Withdrawal of ground water from storage by heavy pumping not only provides a needed irrigation water supply, but it also lowers the ground-water level and makes storage space available in which to conserve excess water during periods of heavy runoff. A storage capacity estimated to be 93 million acre-feet to a depth of 200 feet is available in this ground-water reservoir. This is about nine times the combined capacity of the existing and proposed surface-water reservoirs in the San Joaquin Valley under the California Water Plan. The landforms of the San Joaquin Valley include dissected uplands, low plains and fans, river flood plains and channels, and overflow lands and lake bottoms. Below the land surface, unconsolidated sediments derived from the surrounding mountain highlands extend downward for hundreds of feet. These unconsolidated deposits, consisting chiefly of alluvial deposits, but including some widespread lacustrine sediments, are the principal source of ground water in the valley. Ground water occurs under confined and unconfined conditions in the San Joaquin Valley. In much of the western, central, and southeastern parts of the valley, three distinct ground-water reservoirs are present. In downward succession these are 1) a body of unconfined and semiconfined fresh water in alluvial deposits of Recent, Pleistocene, and possibly later Pliocene age, overlying the Corcoran clay member of the Tulare formation; 2) a body of fresh water confined beneath the Corcoran clay member, which

Design and results of the Mariano Lake-Lake Valley drilling project, Northwestern New Mexico

International Nuclear Information System (INIS)

Kirk, A.R.; Huffman, A.C. Jr.; Zech, R.S.

1986-01-01

This drilling project included 12 holes along a north-south-trending line from Mariano Lake to Lake Valley, New Mexico, near the southern margin of the San Juan basin. Of a total 33,075 ft (10,088m) drilled, 4,550 ft (1,388m) were cored in the stratigraphic interval that included the basal part of the Dakota Sandstone, the Brushy Basin and Westwater Canyon Members of the Morrison Formation, and the upper part of the Recapture Member of the Morrison Formation. The project objectives were (1) to provide cores and geophysical logs for study of the sedimentology, petrography, geochemistry, and mineralization in the uranium-bearing Westwater Canyon Member; (2) to provide control for a detailed seismic study of Morrison stratigraphy and basement structures; (3) to define and correlate the stratigraphy of Cretaceous coal-bearing units; (4) to supply background data for studies of ground-water flow pattern and ground-water quality; and (5) to provide data to aid resource assessment or uranium and coal. The project design included selection of (1) drill-hole locations to cross known ore and depositional trends in the Morrison Formation; (2) a coring interval to include the uranium-bearing unit and adjacent units; geophysical logs for lithologic correlations, quantitative evaluation of uranium mineralization, qualitative detection of coal beds, preparation of synthetic seismograms, and magnetic susceptibility studies of alteration in the Morrison; and (3) a high-salinity mud program to enhance core recovery

Middle Pleistocene infill of Hinkley Valley by Mojave River sediment and associated lake sediment: Depositional architecture and deformation by strike-slip faults

Science.gov (United States)

Miller, David; Haddon, Elizabeth; Langenheim, Victoria; Cyr, Andrew J.; Wan, Elmira; Walkup, Laura; Starratt, Scott W.

2018-01-01

Hinkley Valley in the Mojave Desert, near Barstow about 140 km northeast of Los Angeles and midway between Victorville Valley and the Lake Manix basin, contains a thick sedimentary sequence delivered by the Mojave River. Our study of sediment cores drilled in the valley indicates that Hinkley Valley was probably a closed playa basin with stream inflow from four directions prior to Mojave River inflow. The Mojave River deposited thick and laterally extensive clastic wedges originating from the southern valley that rapidly filled much of Hinkley Valley. Sedimentary facies representing braided stream, wetland, delta, and lacustrine depositional environments all are found in the basin fill; in some places, the sequence is greater than 74 m (245 ft) thick. The sediment is dated in part by the presence of the ~631 ka Lava Creek B ash bed low in the section, and thus represents sediment deposition after Victorville basin was overtopped by sediment and before the Manix basin began to be filled. Evidently, upstream Victorville basin filled with sediment by about 650 ka, causing the ancestral Mojave River to spill to the Harper and Hinkley basins, and later to Manix basin.Initial river sediment overran wetland deposits in many places in southern Hinkley Valley, indicating a rapidly encroaching river system. These sediments were succeeded by a widespread lake (“blue” clay) that includes the Lava Creek B ash bed. Above the lake sediment lies a thick section of interlayered stream sediment, delta and nearshore lake sediment, mudflat and/or playa sediment, and minor lake sediment. This stratigraphic architecture is found throughout the valley, and positions of lake sediment layers indicate a successive northward progression in the closed basin. A thin overlapping sequence at the north end of the valley contains evidence for a younger late Pleistocene lake episode. This late lake episode, and bracketing braided stream deposits of the Mojave River, indicate that the river

Crop intensification options and trade-offs with the water balance in the Central Rift Valley of Ethiopia

NARCIS (Netherlands)

Debas, Mezegebu

2016-01-01

The Central Rift Valley (CRV) of Ethiopia is a closed basin for which claims on land and water have strongly increased over the past decade resulting in over-exploitation of the resources. A clear symptom is the declining trend in the water level of the terminal Lake Abyata. The actual

Sulphate balance of lakes and shallow groundwater in the Vasavere buried valley, Northeast Estonia

International Nuclear Information System (INIS)

Erg, K.

2003-01-01

Groundwater is an important component of many water resource systems supplying water for domestic use, industry, and agriculture. In recent years the attention has been focused on groundwater contamination by mine water. Decline in mining activities and introduction of new technologies together with economic measures has improved the situation but much should be done during coming years. Oil shale mining brings about changes in the groundwater regime and chemical composition. The correlation between the natural (meteorological and hydrological) and technogenic (mining-technological, hydrogeological, hydrochemical) factors caused by the oil shale mining in the Vasavere valley during 1970-2000 has been studied. As a result of extensive drainage of mining shafts and water consumption, the groundwater table has noticeably lowered in the area and sulphate content in lakes and groundwater is especially high

Source Water Assessment for the Las Vegas Valley Surface Waters

Science.gov (United States)

Albuquerque, S. P.; Piechota, T. C.

2003-12-01

The 1996 amendment to the Safe Drinking Water Act of 1974 created the Source Water Assessment Program (SWAP) with an objective to evaluate potential sources of contamination to drinking water intakes. The development of a Source Water Assessment Plan for Las Vegas Valley surface water runoff into Lake Mead is important since it will guide future work on source water protection of the main source of water. The first step was the identification of the watershed boundary and source water protection area. Two protection zones were delineated. Zone A extends 500 ft around water bodies, and Zone B extends 3000 ft from the boundaries of Zone A. These Zones extend upstream to the limits of dry weather flows in the storm channels within the Las Vegas Valley. After the protection areas were identified, the potential sources of contamination in the protection area were inventoried. Field work was conducted to identify possible sources of contamination. A GIS coverage obtained from local data sources was used to identify the septic tank locations. Finally, the National Pollutant Discharge Elimination System (NPDES) Permits were obtained from the State of Nevada, and included in the inventory. After the inventory was completed, a level of risk was assigned to each potential contaminating activity (PCA). The contaminants of concern were grouped into five categories: volatile organic compounds (VOCs), synthetic organic compounds (SOCs), inorganic compounds (IOCs), microbiological, and radionuclides. The vulnerability of the water intake to each of the PCAs was assigned based on these five categories, and also on three other factors: the physical barrier effectiveness, the risk potential, and the time of travel. The vulnerability analysis shows that the PCAs with the highest vulnerability rating include septic systems, golf courses/parks, storm channels, gas stations, auto repair shops, construction, and the wastewater treatment plant discharges. Based on the current water quality

The carbon stable isotope biogeochemistry of streams, Taylor Valley, Antarctica

International Nuclear Information System (INIS)

Lyons, W.B.; Leslie, D.L.; Harmon, R.S.; Neumann, K.; Welch, K.A.; Bisson, K.M.; McKnight, D.M.

2013-01-01

Highlights: ► δ 13 C-DIC reported from McMurdo Dry Valleys, Antarctica, streams. ► Stream water δ 13 C PDB values range −9.4‰ to +5.1‰, largely inorganic in character. ► Atmospheric exchange is the dominant control on δ 13 C-DIC. - Abstract: The McMurdo Dry Valleys region of Antarctica is the largest ice-free region on the continent. This study reports the first C stable isotope measurements for dissolved inorganic C present in ephemeral streams in four dry valleys that flow for four to twelve weeks during the austral summer. One of these valleys, Taylor Valley, has been the focus of the McMurdo Dry Valleys Long-Term Ecological Research (MCM-LTER) program since 1993. Within Taylor Valley, numerous ephemeral streams deliver water to three perennially ice-covered, closed-basin lakes: Lake Fryxell, Lake Hoare, and Lake Bonney. The Onyx River in the Wright Valley, the longest river in Antarctica, flows for 40 km from the Wright Lower Glacier and Lake Brownworth at the foot of the glacier to Lake Vanda. Streamflow in the McMurdo Dry Valley streams is produced primarily from glacial melt, as there is no overland flow. However, hyporheic zone exchange can be a major hydrogeochemical process in these streams. Depending on landscape position, these streams vary in gradient, channel substrate, biomass abundance, and hyporheic zone extent. This study sampled streams from Taylor, Wright, Garwood, and Miers Valleys and conducted diurnal sampling of two streams of different character in Taylor Valley. In addition, transect sampling was undertaken of the Onyx River in Wright Valley. The δ 13 C PDB values from these streams span a range of greater than 14‰, from −9.4‰ to +5.1‰, with the majority of samples falling between −3‰ and +2‰, suggesting that the C stable isotope composition of dissolved C in McMurdo Dry Valley streams is largely inorganic in character. Because there are no vascular plants on this landscape and no groundwater input to these

Water quality and fish dynamics in forested wetlands associated with an oxbow lake

Science.gov (United States)

Andrews, Caroline S.; Miranda, Leandro E.; Kroger, Robert

2015-01-01

Forested wetlands represent some of the most distinct environments in the Lower Mississippi Alluvial Valley. Depending on season, water in forested wetlands can be warm, stagnant, and oxygen-depleted, yet may support high fish diversity. Fish assemblages in forested wetlands are not well studied because of difficulties in sampling heavily structured environments. During the April–July period, we surveyed and compared the water quality and assemblages of small fish in a margin wetland (forested fringe along a lake shore), contiguous wetland (forested wetland adjacent to a lake), and the open water of an oxbow lake. Dissolved-oxygen levels measured hourly 0.5 m below the surface were higher in the open water than in either of the forested wetlands. Despite reduced water quality, fish-species richness and catch rates estimated with light traps were greater in the forested wetlands than in the open water. The forested wetlands supported large numbers of fish and unique fish assemblages that included some rare species, likely because of their structural complexity. Programs developed to refine agricultural practices, preserve riparian zones, and restore lakes should include guidance to protect and reestablish forested wetlands.

Water-quality and lake-stage data for Wisconsin lakes, water year 2014

Science.gov (United States)

Manteufel, S. Bridgett; Robertson, Dale M.

2017-05-25

IntroductionThe U.S. Geological Survey (USGS), in cooperation with local and other agencies, collects data at selected lakes throughout Wisconsin. These data, accumulated over many years, provide a database for developing an improved understanding of the water quality of lakes. To make these data available to interested parties outside the USGS, the data are published annually in this report series. The locations of water-quality and lake-stage stations in Wisconsin for water year 2014 are shown in figure 1. A water year is the 12-month period from October 1 through September 30. It is designated by the calendar year in which it ends. Thus, the periodOctober 1, 2013, through September 30, 2014, is called “water year 2014.”The purpose of this report is to provide information about the chemical and physical characteristics of Wisconsin lakes. Data that have been collected at specific lakes, and information to aid in the interpretation of those data, are included in this report. Data collected include measurements of in-lake water quality and lake stage. Time series of Secchi depths, surface total phosphorus, and chlorophyll a concentrations collected during nonfrozen periods are included for many lakes. Graphs of vertical profiles of temperature, dissolved oxygen, pH, and specific conductance are included for sites where these parameters were measured. Descriptive information for each lake includes the location of the lake, area of the lake’s watershed, period for which data are available, revisions to previously published records, and pertinent remarks. Additional data, such as streamflow and water quality in tributary and outlet streams of some of the lakes, are published online at http://nwis.waterdata.usgs.gov/wi/nwis.Water-resources data, including stage and discharge data at most streamflow-gaging stations, are available online. The Wisconsin Water Science Center’s home page is at https://www.usgs.gov/centers/wisconsin-water-science-center. Information

Micro-hole and multigrain quartz luminescence dating of Paleodeltas at Lake Fryxell, McMurdo Dry Valleys (Antarctica), and relevance for lake history

DEFF Research Database (Denmark)

Berger, G.W.; Doran, P.T.; Thomsen, Kristina Jørkov

2013-01-01

Relict (perched) lacustrine deltas around the perennially ice-covered lakes in the Taylor Valley, Antarctica, imply that these lakes were up to 40 times larger in area than at present since the last glacial maximum (LGM). These deltas have been used to constrain ice-margin positions in Taylor Val...

Brief description as of April, 1968, of the geology and hydrology of the Lake Minnequa area, Pueblo, Colorado, and suggested solutions for trouble caused by a high water table

Science.gov (United States)

Scott, Glenn R.

1972-01-01

Lake Minnequa lies in a poorly drained broad upland buried valley west of the valley of Salt Creek. Immediately north of Lake Minnequa the buried valley is sharply constricted in sees. 11 and 12, T. 21 S., R. 65 W., where it is entrenched in a buried ridge of bedrock (see geologic map).  The bedrock throughout the buried valley is composed of calcareous shale, limestone, and chalk of the Smoky Hill Shale Member of the Niobrara Formation.  These beds are relatively impermeable to the flow of ground water, but contribute large quantities of sodium sulfate to both the surface and ground water.

Application of environmental isotopes to determine the cause of rising water levels in Lake Beseka, Ethiopia

International Nuclear Information System (INIS)

Zemedagegnehu, E.; Travi, Y.; Aggarwal, P.

1999-01-01

Water level in Lake Beskea, located in the Ethiopian Rift Valley, has been rising continuously for the last about 30 years. The surface area of the lake has increased from about 6 Km 2 to the present 40 Km 2 and has posed serious problems for environmental management, including inundation of grazing and cultivated lands and, potentially, railway tracks. Historically, the lake received recharge from precipitation, surface runoff in the catchment, groundwater discharge, surface runoff from nearby thermal springs. As the lake levels have risen, the thermal springs are now submerged. An increase in the discharge form these thermal springs may be the original cause of lake water rise, or they may have been submerged as a result of the rising water level. An initial study conducted in the 1970s attributed the rising lake levels to increased runoff from adjoining irrigated areas. However, stricter controls on irrigation runoff failed to check the rising lake levels. A multi-disciplinary study, including geophysical, hydrological, geochemical, isotopic, and modeling techniques was then initiated to determine the cause(s) of lake level rise. Results of piezometric and geophysical surveys indicate that the principal cause of rising water levels may be the increased inflow from submerged springs in the southwestern portion of the lake

Groundwater quality in the Owens Valley, California

Science.gov (United States)

Dawson, Barbara J. Milby; Belitz, Kenneth

2012-01-01

Groundwater provides more than 40 percent of California’s drinking water. To protect this vital resource, the State of California created the Groundwater Ambient Monitoring and Assessment (GAMA) Program. The Priority Basin Project of the GAMA Program provides a comprehensive assessment of the State’s groundwater quality and increases public access to groundwater-quality information. Owens Valley is one of the study areas being evaluated. The Owens study area is approximately 1,030 square miles (2,668 square kilometers) and includes the Owens Valley groundwater basin (California Department of Water Resources, 2003). Owens Valley has a semiarid to arid climate, with average annual rainfall of about 6 inches (15 centimeters). The study area has internal drainage, with runoff primarily from the Sierra Nevada draining east to the Owens River, which flows south to Owens Lake dry lakebed at the southern end of the valley. Beginning in the early 1900s, the City of Los Angeles began diverting the flow of the Owens River to the Los Angeles Aqueduct, resulting in the evaporation of Owens Lake and the formation of the current Owens Lake dry lakebed. Land use in the study area is approximately 94 percent (%) natural, 5% agricultural, and 1% urban. The primary natural land cover is shrubland. The largest urban area is the city of Bishop (2010 population of 4,000). Groundwater in this basin is used for public and domestic water supply and for irrigation. The main water-bearing units are gravel, sand, silt, and clay derived from surrounding mountains. Recharge to the groundwater system is primarily runoff from the Sierra Nevada, and by direct infiltration of irrigation. The primary sources of discharge are pumping wells, evapotranspiration, and underflow to the Owens Lake dry lakebed. The primary aquifers in Owens Valley are defined as those parts of the aquifers corresponding to the perforated intervals of wells listed in the California Department of Public Health database

Water-quality and lake-stage data for Wisconsin lakes, water years 2012–2013

Science.gov (United States)

Manteufel, S. Bridgett; Robertson, Dale M.

2017-05-25

IntroductionThe U.S. Geological Survey (USGS), in cooperation with local and other agencies, collects data at selected lakes throughout Wisconsin. These data, accumulated over many years, provide a data base for developing an improved understanding of the water quality of lakes. To make these data available to interested parties outside the USGS, the data are published annually in this report series. The locations of water-quality and lake-stage stations in Wisconsin for water year 2012 are shown in figure 1. A water year is the 12-month period from October 1 through September 30. It is designated by the calendar year in which it ends. Thus, the period October 1, 2011 through September 30, 2012, is called “water year 2012.”The purpose of this report is to provide information about the chemical and physical characteristics of Wisconsin lakes. Data that have been collected at specific lakes, and information to aid in the interpretation of those data, are included in this report. Data collected include measurements of in-lake water quality and lake stage. Time series of Secchi depths, surface total phosphorus and chlorophyll a concentrations collected during non-frozen periods are included for all lakes. Graphs of vertical profiles of temperature, dissolved oxygen, pH, and specific conductance are included for sites where these parameters were measured. Descriptive information for each lake includes: location of the lake, area of the lake’s watershed, period for which data are available, revisions to previously published records, and pertinent remarks. Additional data, such as streamflow and water quality in tributary and outlet streams of some of the lakes, are published online at http://nwis.waterdata.usgs.gov/wi/nwis.Water-resources data, including stage and discharge data at most streamflow-gaging stations, are available online. The Wisconsin Water Science Center’s home page is at https://www.usgs.gov/centers/wisconsin-water-science-center. Information on

Speciation of selected trace elements in three Ethiopian Rift Valley Lakes (Koka, Ziway, and Awassa) and their major inflows

International Nuclear Information System (INIS)

Masresha, Alemayehu E.; Skipperud, Lindis; Rosseland, Bjorn Olav; Zinabu, G.M.; Meland, Sondre; Teien, Hans-Christian; Salbu, Brit

2011-01-01

The Ethiopian Rift Valley Lakes (ERVLs) are water resources which have considerable environmental, economic and cultural importance. However, there is an increasing concern that increasing human activities around these lakes and their main inflows can result in increased contamination of these water bodies. Information on total concentrations of some trace elements is available for these lakes and their inflows; however, data on the trace element speciation is lacking. Therefore, the objective of this study was to determine the low molecular mass (LMM) trace element species and also, evaluate the influence of flooding episodes on the LMM trace element fractions. At-site size and charge fractionation system was used for sampling of water from the lakes Koka, Ziway and Awassa and their main inflows during the dry and wet seasons. The results showed that chromium (Cr), manganese (Mn), cobalt (Co), nickel (Ni), copper (Cu), zinc (Zn), and lead (Pb) in Lake Koka and its inflows as well as in Lake Ziway were predominantly present as HMM (high molecular mass, i.e., > 10 kDa) forms, while arsenic (As), selenium (Se), cadmium (Cd) were more mobile during the dry season. In Lake Awassa, all except Cr and Mn were predominantly found as LMM species (low molecular mass, i.e. < 10 kDa) which can be attributed to the high concentrations of LMM DOC (dissolved organic carbon). During the wet season, results from the Lake Koka and its inflows showed that all trace elements were predominantly associated with HMM forms such as colloids and particles, demonstrating that the mobility of elements was reduced during the wet season. The colloidal fraction of elements such as Cr, Ni, and Cd was also correlated with dissolved Fe. As the concentration of LMM trace element species are very low, the mobility, biological uptake and the potential environmental impact should be low.

Characterize the hydrogeological properties and probe the stress field in Salt Lake Valley, Utah using SAR imagery

Science.gov (United States)

Hu, X.; Lu, Z.; Barbot, S.; Wang, T.

2017-12-01

Aquifer skeletons deform actively in response to the groundwater redistribution and hydraulic head changes with varied time scales of delay and sensitivity, that can also, in some instances, trigger earthquakes. However, determining the key hydrogeological properties and understanding the interactions between aquifer and seismicity generally requires the analysis of dense water level data combined with expensive drilling data (borehole breakouts). Here we investigate the spatiotemporal correlation among ground motions, hydrological changes, earthquakes, and faults in Salt Lake Valley, Utah, based on InSAR observations from ENVISAT ASAR (2004-2010) and Sentinel-1A (2015-2016). InSAR results show a clear seasonal and long-term correlation between surface uplift/subsidence and groundwater recharge/discharge, with evidence for an average net uplift of 15 mm/yr for a period of 7 years. The long-term uplift, remarkably bounded by faults, reflects a net increase in pore pressure associated with prolonged water recharge probably decades ago. InSAR-derived ground deformation and its correlation with head variations allow us to quantify hydrogeological properties - decay coefficient, storage coefficient, and bulk compressibility. We also model the long-term deformation using a shallow vertical shearing reservoir to constrain its thickness and strain rate. InSAR-derived deformation help reveal the coupled hydrological and tectonic processes in Salt Lake Valley: the embedded faults disrupt the groundwater flow and partition the hydrological units, and the pore pressure changes rearrange the aquifer skeleton and modulate the stress field, which may affect the basin-wide seismicity.

Surficial geologic map of the Red Rock Lakes area, southwest Montana

Science.gov (United States)

Pierce, Kenneth L.; Chesley-Preston, Tara L.; Sojda, Richard L.

2014-01-01

The Centennial Valley and Centennial Range continue to be formed by ongoing displacement on the Centennial fault. The dominant fault movement is downward, creating space in the valley for lakes and the deposition of sediment. The Centennial Valley originally drained to the northeast through a canyon now represented by a chain of lakes starting with Elk Lake. Subsequently, large landslides blocked and dammed the drainage, which created Lake Centennial, in the Centennial Valley. Sediments deposited in this late Pleistocene lake underlie much of the valley floor and rest on permeable sand and gravel deposited when the valley drained to the northeast. Cold Pleistocene climates enhanced colluvial supply of gravelly sediment to mountain streams and high peak flows carried gravelly sediment into the valley. There, the lower gradient of the streams resulted in deposition of alluvial fans peripheral to Lake Centennial as the lake lowered through time to the level of the two present lakes. Pleistocene glaciers formed in the high Centennial Range, built glacial moraines, and also supplied glacial outwash to the alluvial fans. Winds from the west and south blew sand to the northeast side of the valley building up high dunes. The central part of the map area is flat, sloping to the west by only 0.6 meters in 13 kilometers (2 feet in 8 miles) to form a watery lowland. This lowland contains Upper and Lower Red Rock Lakes, many ponds, and peat lands inside the “water plane,” above which are somewhat steeper slopes. The permeable sands and gravels beneath Lake Centennial sediments provide a path for groundwater recharged from the adjacent uplands. This groundwater leaks upward through Lake Centennial sediments and sustains wetland vegetation into late summer. Upper and Lower Red Rock Lakes are formed by alluvial-fan dams. Alluvial fans converge from both the south and the north to form outlet thresholds that dam the two shallow lakes upstream. The surficial geology aids in

Chemical quality of surface waters in Devils Lake basin, North Dakota

Science.gov (United States)

Swenson, Herbert; Colby, Bruce R.

1955-01-01

Devils Lake basin, a closed basin in northeastern North Dakota, covers about 3,900 square miles of land, the topography of which is morainal and of glacial origin. In this basin lies a chain of waterways, which begins with the Sweetwater group and extends successively through Mauvais Coulee, Devils Lake, East Bay Devils Lake, and East Devils Lake, to Stump Lake. In former years when lake levels were high, Mauvais Coulee drained the Sweetwater group and discharged considerable water into Devils Lake. Converging coulees also transported excess water to Stump Lake. For at least 70 years prior to 1941, Mauvais Coulee flowed only intermittently, and the levels of major lakes in this region gradually declined. Devils Lake, for example, covered an area of about 90,000 acres in 1867 but had shrunk to approximately 6,500 acres by 1941. Plans to restore the recreational appeal of Devils Lake propose the dilution and eventual displacement of the brackish lake water by fresh water that would be diverted from the Missouri River. Freshening of the lake water would permit restocking Devils Lake with fish. Devils and Stump Lake have irregular outlines and numerous windings and have been described as lying in the valley of a preglacial river, the main stem and tributaries of which are partly filled with drift. Prominent morainal hills along the south shore of Devils Lake contrast sharply with level farmland to the north. The mean annual temperature of Devils Lake basin ranges between 36 ? and 42 ? F. Summer temperatures above 100 ? F and winter temperatures below -30 ? Fare not uncommon. The annual precipitation for 77 years at the city of Devils Lake averaged 17.5 inches. Usually, from 75 to 80 percent of the precipitation in the basin falls during the growing season, April to September. From 1867 to 1941 the net fall of the water surface of Devils Lake was about 38 feet. By 1951 the surface had risen fully 14 feet from its lowest altitude, 1,400.9 feet. Since 1951, the level has

Estimation of lake water - groundwater interactions in meromictic mining lakes by modelling isotope signatures of lake water.

Science.gov (United States)

Seebach, Anne; Dietz, Severine; Lessmann, Dieter; Knoeller, Kay

2008-03-01

A method is presented to assess lake water-groundwater interactions by modelling isotope signatures of lake water using meteorological parameters and field data. The modelling of delta(18)O and deltaD variations offers information about the groundwater influx into a meromictic Lusatian mining lake. Therefore, a water balance model is combined with an isotope water balance model to estimate analogies between simulated and measured isotope signatures within the lake water body. The model is operated with different evaporation rates to predict delta(18)O and deltaD values in a lake that is only controlled by weather conditions with neither groundwater inflow nor outflow. Comparisons between modelled and measured isotope values show whether the lake is fed by the groundwater or not. Furthermore, our investigations show that an adaptation of the Craig and Gordon model [H. Craig, L.I. Gordon. Deuterium and oxygen-18 variations in the ocean and the marine atmosphere. In Stable Isotopes in Oceanographic Studies and Paleotemperature, Spoleto, E. Tongiorgi (Ed.), pp. 9-130, Consiglio Nazionale delle Ricerche, Laboratorio di Geologia Nucleare, Pisa (1965).] to specific conditions in temperate regions seems necessary.

New structural/tectonical model and its implication on hydrological thinking and groundwater management - the Lake Tiberias, Jordan Rift Valley

Science.gov (United States)

Inbar, Nimrod; Magri, Fabien; Yellin-Dror, Annat; Rosenthal, Eliahu; Möller, Peter; Siebert, Christian; Guttman, Josef

2014-05-01

Lake Tiberias is a fresh water lake located at the Kinneret basin which is approximately 30 km long and 10 km wide. It comprises a link in the chain of pull-apart basins that characterizes the structure of the conspicuous Jordan Rift Valley (JRV). The basin surface is about 200 m below mean sea level (msl) and basin-fill attains a thickness of up to 8 km. Until recently, studies focused mainly on the upper strata of basin fill. Consequently, a complete three dimensional geological model, including clear view of the tectonic framework at the Kinneret Basin was incomplete. This situation imposes great difficulty in understanding the local hydrological system and as consequence enforce constrains on groundwater management of the regional aquifers that flows towards the lake. A recently proposed structural/tectonical model (Inbar, 2012) enables revaluation of several geohydrological aspects at Sea of Galilee and its surroundings and a new hydrological model based on those findings aims to clarify those aspects with relation to groundwater management. The deep-seated stratigraphical units were seismically studied at the Kinnarot Valley (southern part of Kinneret basin) where sufficient information is available (Inbar, 2012). This study shows the subsidence and northwestward tilting of the basin floor (pre-rift formations) and the flow of thick Late Miocene salt accumulation accordingly. Furthermore, shallower seismic data, collected at the lake itself, shows a suspected salt dome close to the western boundary fault of the basin (Resnikov et al., 2004). Salt flow is now suggested to be a substantial factor in the tectonic play. At the lake surroundings there are several springs and boreholes where brine immerges from an estimated depth of about 2-3 kilometers. Significant differences in brine characteristics raised questions regarding the location of brine traps, flow mechanism and the mixture process between the fresh water and the brine. However, the effect of the

Physico-chemical, morphological and pasting properties of starches extracted from water Chestnuts (Trapa natans from three Lakes of Kashmir, India

Directory of Open Access Journals (Sweden)

Adil Gani

2010-06-01

Full Text Available Studies on physicochemical, morphology and pasting properties of starches extracted from water chestnuts of three Lakes of Kashmir valley (Wular, Anchar and Dal Lakes were conducted to determine their application in different food products. The water chestnut starch from Dal Lake had more oval shaped granules than water chestnut starches from the Wular and the Anchar Lakes.The unique feature of the water chestnut starches were shape of starch granules which looked like horn(s protruding from the surface which did not appear in other starches already studied. Proximate analysis of water chestnut starches showed that average protein content were 0.4%, amylose 29.5 % and ash 0.007 on dry weight basis. Increase in water binding capacity, swelling power and solubility was found over a temperature range of 50-90ºC. Water chestnut starches showed an increase in syneresis during freeze thaw cycles and decline in paste clarity upon storage. Starch extracted from the water chestnuts of the Dal Lake showed higher water binding capacity, swelling, solubility, past clarity, freeze thaw stability, peak viscosity, final viscosity and lower protein content, amylose content, pasting temperature and gel firmness than starches extracted from water chestnuts of the Wular and the Anchar Lakes.

The Importance of Lake Overflow Floods for Early Martian Landscape Evolution: Insights From Licus Vallis

Science.gov (United States)

Goudge, T. A.; Fassett, C. I.

2017-01-01

Open-basin lake outlet valleys are incised when water breaches the basin-confining topography and overflows. Outlet valleys record this flooding event and provide insight into how the lake and surrounding terrain evolved over time. Here we present a study of the paleolake outlet Licus Vallis, a >350 km long, >2 km wide, >100 m deep valley that heads at the outlet breach of an approx.30 km diameter impact crater. Multiple geomorphic features of this valley system suggest it records a more complex evolution than formation from a single lake overflow flood. This provides unique insight into the paleohydrology of lakes on early Mars, as we can make inferences beyond the most recent phase of activity..

Numerical simulation of ground-water flow through glacial deposits and crystalline bedrock in the Mirror Lake area, Grafton County, New Hampshire

Science.gov (United States)

Tiedeman, Claire; Goode, Daniel J.; Hsieh, Paul A.

1997-01-01

This report documents the development of a computer model to simulate steady-state (long-term average) flow of ground water in the vicinity of Mirror Lake, which lies at the eastern end of the Hubbard Brook valley in central New Hampshire. The 10-km2 study area includes Mirror Lake, the three streams that flow into Mirror Lake, Leeman's Brook, Paradise Brook, and parts of Hubbard Brook and the Pemigewasset River. The topography of the area is characterized by steep hillsides and relatively flat valleys. Major hydrogeologic units include glacial deposits, composed of till containing pockets of sand and gravel, and fractured crystalline bedrock, composed of schist intruded by granite, pegmatite, and lamprophyre. Ground water occurs in both the glacial deposits and bedrock. Precipitation and snowmelt infiltrate to the water table on the hillsides, flow downslope through the saturated glacial deposits and fractured bedrock, and discharge to streams and to Mirror Lake. The model domain includes the glacial deposits, the uppermost 150m of bedrock, Mirror Lake, the layer of organic sediments on the lake bottom, and streams and rivers within the study area. A streamflow routing package was included in the model to simulate baseflow in streams and interaction between streams and ground water. Recharge from precipitation is assumed to be areally uniform, and riparian evapotranspiration along stream banks is assumed negligible. The spatial distribution of hydraulic conductivity is represented by dividing the model domain into several zones, each having uniform hydraulic properties. Local variations in recharge and hydraulic conductivities are ignored; therefore, the simulation results characterize the general ground-water system, not local details of ground-water movement. The model was calibrated using a nonlinear regression method to match hydraulic heads measured in piezometers and wells, and baseflow in three inlet streams to Mirror Lake. Model calibration indicates that

Hydrogeologic implications of increased septic-tank-soil-absorption system density, Ogden Valley, Weber County, Utah

Science.gov (United States)

Lowe, Mike; Miner, Michael L.; ,

1990-01-01

Ground water in Ogden Valley occurs in perched, confined, and unconfined aquifers in the valley fill to depths of 600 feet and more. The confined aquifer, which underlies only the western portion of the valley, is overlain by cleyey silt lacustrine sediments probably deposited during the Bonneville Basin's Little Valley lake cycle sometime between 90,000 and 150,000 years ago. The top of this cleyey silt confining layer is generally 25 to 60 feet below the ground surface. Unconfined conditions occur above and beyond the outer margin of the confining layer. The sediments overlying the confining layer are primarily Lake Bonneville deposits. Water samples from springs, streams, and wells around Pineview Reservoir, and from the reservoir itself, were collected and analyzed. These samples indicate that water quality in Ogden Valley is presently good. Average nitrate concentrations in the shallow unconfined aquifer increase toward the center of Ogden Valley. This trend was not observed in the confined aquifer. There is no evidence, however, of significant water-quality deterioration, even in the vicinity of Huntsville, a town that has been densely developed using septic-tank-soil-absorption systems for much of the time since it was founded in 1860.

77 FR 27001 - Proposed Establishment of the Ancient Lakes of Columbia Valley Viticultural Area

Science.gov (United States)

2012-05-08

... comments that TTB receives about this proposal by appointment at the TTB Information Resource Center, 1310... and avoid any potential confusion with any other locations referred to as ``Ancient Lakes... such usage. The newspaper article concerned a geological tour of the Quincy Valley and listed one of...

Delineating the Drainage Structure and Sources of Groundwater Flux for Lake Basaka, Central Rift Valley Region of Ethiopia

Directory of Open Access Journals (Sweden)

Megersa Olumana Dinka

2017-11-01

Full Text Available As opposed to most of the other closed basin type rift valley lakes in Ethiopia, Lake Basaka is found to be expanding at an alarming rate. Different studies indicated that the expansion of the lake is challenging the socio-economics and environment of the region significantly. This study result and previous reports indicated that the lake’s expansion is mostly due to the increased groundwater (GW flux to the lake. GW flux accounts for about 56% of the total inflow in recent periods (post 2000 and is found to be the dominant factor for the hydrodynamics and existence of the lake. The analysis of the drainage network for the area indicates the existence of a huge recharge area on the western and upstream side of the catchment. This catchment has no surface outlet; hence most of the incoming surface runoff recharges the GW system. The recharge area is the main source of GW flux to the lake. In addition to this, the likely sources/causes of GW flux to the lake could be: (i an increase of GW recharge following the establishment of irrigation schemes in the region; (ii subsurface inflow from far away due to rift system influence, and (iii lake neotectonism. Overall, the lake’s expansion has damaging effect to the region, owing to its poor water quality; hence the identification of the real causes of GW flux and mitigation measures are very important for sustainable lake management. Therefore a comprehensive and detailed investigation of the parameters related to GW flux and the interaction of the lake with the GW system of the area is highly recommended.

Subsurface imaging reveals a confined aquifer beneath an ice-sealed Antarctic lake

DEFF Research Database (Denmark)

Dugan, H. A.; Doran, P. T.; Tulaczyk, S.

2015-01-01

Liquid water oases are rare under extreme cold desert conditions found in the Antarctic McMurdo Dry Valleys. Here we report geophysical results that indicate that Lake Vida, one of the largest lakes in the region, is nearly frozen and underlain by widespread cryoconcentrated brine. A ground...... this zone to be a confined aquifer situated in sediments with a porosity of 23-42%. Discovery of this aquifer suggests that subsurface liquid water may be more pervasive in regions of continuous permafrost than previously thought and may represent an extensive habitat for microbial populations. Key Points...... Geophysical survey finds low resistivities beneath a lake in Antarctic Dry Valleys Liquid brine abundant beneath Antarctic lake Aquifer provides microbial refugium in cold desert environment...

Late Pleistocene to Holocene lake levels of Lake Warner, Oregon (USA) and their effect on archaeological site distribution patterns

Science.gov (United States)

Wriston, T.; Smith, G. M.

2017-12-01

Few chronological controls are available for the rise and fall of small pluvial lake systems in the Northwestern Great Basin. Within Warner Basin this control was necessary for interpretation of known archaeological sites and for predicting where evidence of its earliest inhabitants might be expected. We trenched along relic beach ridges of Lake Warner, surveyed a stratified sample of the area for archaeological sites, and excavated some sites and a nearby rockshelter. These efforts produced new ages that we used to construct a lake level curve for Lake Warner. We found that the lake filled the valley floor between ca. 30,000 cal yr BP and ca. 10,300 cal yr BP. In nearby basins, several oscillations are evident before ca. 21,100 cal yr BP, but a steep rise to the LGM maximum occurred between 21,000 and 20,000 cal yr BP. Lake Warner likely mirrored these changes, dropped to the valley floor ca. 18,340 cal yr BP, and then rose to its maximum highstand when its waters briefly reached 1454 m asl. After this highstand the lake receded to moderately high levels. Following ca. 14,385 cal yr BP, the lake oscillated between moderate to moderately-high levels through the Bolling-Allerod interstadials and into the Younger Dryas stadial. The basin's first occupants arrived along its shore around this time, while the lake still filled the valley floor. These earliest people carried either Western Stemmed or Clovis projectile points, both of which are found along the lake margin. The lake receded into the valley floor ca. 10,300 cal yr BP and dune development began, ringing wetlands and small lakes that persisted in the footprint of the once large lake. By the time Mazama tephra fell 7,600 cal yr BP it blanketed pre-existing dunes and marsh peats. Our Lake Warner lake level curve facilitates interdisciplinary testing and refinement of it and similar curves throughout the region while helping us understand the history of lake and the people who lived along its shores.

Water quality of Lake Austin and Town Lake, Austin, Texas

Science.gov (United States)

Andrews, Freeman L.; Wells, Frank C.; Shelby, Wanda J.; McPherson, Emma

1988-01-01

Lake Austin and Town Lake are located on the Colorado River in Travis County, central Texas, and serve as a source of water for municipal and industrial water supplies, electrical-power generation, and recreation for more than 500,000 people in the Austin metropolitan area. Lake Austin, located immediately downstream of Lake Travis, extends for more than 20 miles into the western edge of the city of Austin. Town Lake extends through the downtown area of the city of Austin for nearly 6 miles where the Colorado River is impounded by Longhorn Dam.

Hydrogeologic setting, water budget, and preliminary analysis of ground-water exchange at Lake Starr, a seepage lake in Polk County, Florida

Science.gov (United States)

Swancar, Amy; Lee, T.M.; O'Hare, T. M.

2000-01-01

Lake Starr, a 134-acre seepage lake of multiple-sinkhole origin on the Lake Wales Ridge of central Florida, was the subject of a detailed water-budget study from August 1996 through July 1998. The study monitored the effects of hydrogeologic setting, climate, and ground-water pumping on the water budget and lake stage. The hydrogeologic setting of the Lake Starr basin differs markedly on the two sides of the lake. Ground water from the surficial aquifer system flows into the lake from the northwest side of the basin, and lake water leaks out to the surficial aquifer system on the southeast side of the basin. Lake Starr and the surrounding surficial aquifer system recharge the underlying Upper Floridan aquifer. The rate of recharge to the Upper Floridan aquifer is determined by the integrity of the intermediate confining unit and by the downward head gradient between the two aquifers. On the inflow side of the lake, the intermediate confining unit is more continuous, allowing ground water from the surficial aquifer system to flow laterally into the lake. Beneath the lake and on the southeast side of the basin, breaches in the intermediate confining unit enhance downward flow to the Upper Floridan aquifer, so that water flows both downward and laterally away from the lake through the ground-water flow system in these areas. An accurate water budget, including evaporation measured by the energy-budget method, was used to calculate net ground-water flow to the lake, and to do a preliminary analysis of the relation of net ground-water fluxes to other variables. Water budgets constructed over different timeframes provided insight on processes that affect ground-water interactions with Lake Starr. Weekly estimates of net ground-water flow provided evidence for the occurrence of transient inflows from the nearshore basin, as well as the short-term effects of head in the Upper Floridan aquifer on ground-water exchange with the lake. Monthly water budgets showed the effects

Comparison of the hydrogeology and water quality of a ground-water augmented lake with two non-augmented lakes in northwest Hillsborough County, Florida

Science.gov (United States)

Metz, Patricia A.; Sacks, Laura A.

2002-01-01

The hydrologic effects associated with augmenting a lake with ground water from the Upper Floridan aquifer were examined in northwest Hillsborough County, Florida, from June 1996 through May 1999. The hydrogeology, ground-water flow patterns, water budgets, and water-quality characteristics were compared between a lake that has been augmented for more than 30 years (Round Lake) and two nearby nonaugmented lakes (Dosson Lake and Halfmoon Lake). Compared to the other study lakes, Round Lake is in a more leakage-dominated hydrogeologic setting. The intermediate confining unit is thin or highly breached, which increases the potential for vertical ground-water flow. Round Lake has the least amount of soft, organic lake-bottom sediments and the lake bottom has been dredged deeper and more extensively than the other study lakes, which could allow more leakage from the lake bottom. The area around Round Lake has experienced more sinkhole activity than the other study lakes. During this study, three sinkholes developed around the perimeter of the lake, which may have further disrupted the intermediate confining unit.Ground-water flow patterns around Round Lake were considerably different than the nonaugmented lakes. For most of the study, groundwater augmentation artificially raised the level of Round Lake to about 2 to 3 feet higher than the adjacent water table. As a result, lake water recharged the surficial aquifer around the entire lake perimeter, except during very wet periods when ground-water inflow occurred around part of the lake perimeter. The non-augmented lakes typically had areas of ground-water inflow and areas of lake leakage around their perimeter, and during wet periods, ground-water inflow occurred around the entire lake perimeter. Therefore, the area potentially contributing ground water to the non-augmented lakes is much larger than for augmented Round Lake. Vertical head loss within the surficial aquifer was greater at Round Lake than the other study

New insight on the water management in Ica Valley-Peru

Science.gov (United States)

Guttman, Joseph; Berger, Diego

2014-05-01

The Andes divide Peru into three natural drainage basins: Pacific basin, Atlantic basin and Lake Titicaca basin. According to the National Water Authority (ANA), the Pacific basin is the driest basin. The bulk of water that feed the local aquifers in the coastal Pacific region is coming from rivers that flow west from the Andes. One of them is the Ica River- source of the Ica Aquifer and the Pampas de Villacuri Aquifer. The Ica River flows in a graben that was created by a series of faults. The graben is filled with sand and gravel with interbeded and lenses of clay. The aquifer thickness varies between 25 meters to more than 200 meters. The Ica Valley has an extension of 7700 km2 and belongs to the Province of Ica, the second larger economic center in Peru. The Valley is located in the hyperarid region of the Southern Coastal area of Peru with a few millimeters of precipitation per year. The direct recharge is almost zero. The recharge into the Ica Valley aquifer is comes indirectly by infiltration of storm water through the riverbed generates in the Andes, through irrigation canals and by irrigation return flow. In this hyperarid region, local aquifers like the Ica Valley are extremely valuable resources to local populations and are the key sources of groundwater for agriculture and population needs. Therefore, these aquifers play a crucial role in providing people with water and intense attention should be given to manage the water sector properly and to keep the aquifer sustainable for future generations. The total pumping (from rough estimations) is much greater than the direct and indirect recharge. The deficit in the water balance is reflected in large water level decline, out of operation of shallow wells and the ascending of saline water from deeper layers. The change from flood irrigation that contributes about 35-40% of the water to the aquifer, to drip irrigation dramatically reduces the amount of water that infiltrates into the sub-surface from the

Water and waste water management Generation Victoria - Latrobe Valley

Energy Technology Data Exchange (ETDEWEB)

Longmore, G. [Hazelwood Power Corporation, VIC (Australia); Pacific Power (International) Pty. Ltd., Sydney, NSW (Australia)

1995-12-31

Water is a necessary resource for coal fired power plant and waste water is generated. The efficient management of water and waste water systems becomes an important operational environmental factor. This paper describes the development and implementation of a ten year water and waste water management strategy for the Latrobe Valley Group of brown coal fired power stations in Victoria. In early 1991, a team was put together of representatives from each power site to develop the strategy entitled `SECV Latrobe Valley Water and Wastewater Management Strategy`. The strategy was developed with extensive public consultation, which was a factor in protracting the process such that the final document was not promulgated until late 1992. However, the final comprehensive document endorsed and agreed by management, has since attracted favourable comment as a model of its type. (author). 2 figs.

Water and waste water management Generation Victoria - Latrobe Valley

International Nuclear Information System (INIS)

Longmore, G.

1995-01-01

Water is a necessary resource for coal fired power plant and waste water is generated. The efficient management of water and waste water systems becomes an important operational environmental factor. This paper describes the development and implementation of a ten year water and waste water management strategy for the Latrobe Valley Group of brown coal fired power stations in Victoria. In early 1991, a team was put together of representatives from each power site to develop the strategy entitled 'SECV Latrobe Valley Water and Wastewater Management Strategy'. The strategy was developed with extensive public consultation, which was a factor in protracting the process such that the final document was not promulgated until late 1992. However, the final comprehensive document endorsed and agreed by management, has since attracted favourable comment as a model of its type. (author). 2 figs

33 CFR 162.132 - Connecting waters from Lake Huron to Lake Erie; communications rules.

Science.gov (United States)

2010-07-01

... 33 Navigation and Navigable Waters 2 2010-07-01 2010-07-01 false Connecting waters from Lake Huron to Lake Erie; communications rules. 162.132 Section 162.132 Navigation and Navigable Waters COAST... NAVIGATION REGULATIONS § 162.132 Connecting waters from Lake Huron to Lake Erie; communications rules. (a...

33 CFR 162.140 - Connecting waters from Lake Huron to Lake Erie; miscellaneous rules.

Science.gov (United States)

2010-07-01

... 33 Navigation and Navigable Waters 2 2010-07-01 2010-07-01 false Connecting waters from Lake Huron to Lake Erie; miscellaneous rules. 162.140 Section 162.140 Navigation and Navigable Waters COAST... NAVIGATION REGULATIONS § 162.140 Connecting waters from Lake Huron to Lake Erie; miscellaneous rules. (a...

33 CFR 162.130 - Connecting waters from Lake Huron to Lake Erie; general rules.

Science.gov (United States)

2010-07-01

... 33 Navigation and Navigable Waters 2 2010-07-01 2010-07-01 false Connecting waters from Lake Huron to Lake Erie; general rules. 162.130 Section 162.130 Navigation and Navigable Waters COAST GUARD... REGULATIONS § 162.130 Connecting waters from Lake Huron to Lake Erie; general rules. (a) Purpose. The...

A radical shift from soft-water to hard-water lake: palaeolimnological evidence from Lake Kooraste Kõverjärv, southern Estonia

Directory of Open Access Journals (Sweden)

Tiiu Alliksaar

2012-11-01

Full Text Available The Water Framework Directive (WFD of the European Union requires the quality of all European water bodies to be examined, and aims to achieve good status by 2015. This study was initiated to assess whether a potential reference lake for identifying lake-type specific reference conditions meets the WFD requirements, of being minimally impacted by human activity during the last centuries. The sediments of Lake Kooraste Kõverjärv were analysed for diatom assemblages and sediment composition; past changes in the lake-water pH and total phosphorus were reconstructed, using quantitative models on sedimentary diatoms. The chronology of sediments was established, using spheroidal fly-ash particles stratigraphy. Palaeolimnological investigations, supported by information from historical maps, revealed that man-made changes around the lake have severely influenced its ecological conditions. The lake, which had been oligotrophic with soft and clear water before the mid-17th century, has been trans­formed into a hard-water lake by modifications to the inflow and outflow. The lake water quality has also been altered by the infiltration of nutrients from a nearby hypertrophic lake that was used for flax retting since the 19th century. Although the ecological status of the lake has remained good despite all these changes, it is still questionable whether to nominate it as a reference lake for stratified hard-water lake types.

Is Lake Chabot Eutrophic?

Science.gov (United States)

Pellegrini, K.; Logan, J.; Esterlis, P.; Lew, A.; Nguyen, M.

2013-12-01

Introduction/Abstract: Lake Chabot is an integral part of the East Bay watershed that provides habitats for animals and recreation for humans year-round. Lake Chabot has been in danger of eutrophication due to excessive dumping of phosphorous and nitrogen into the water from the fertilizers of nearby golf courses and neighboring houses. If the lake turned out to be eutrophified, it could seriously impact what is currently the standby emergency water supply for many Castro Valley residents. Eutrophication is the excessive richness of nutrients such as nitrogen and phosphorus in a lake, usually as a result of runoff. This buildup of nutrients causes algal blooms. The algae uses up most of the oxygen in the water, and when it dies, it causes the lake to hypoxify. The fish in the lake can't breathe, and consequently suffocate. Other oxygen-dependant aquatic creatures die off as well. Needless to say, the eutrophication of a lake is bad news for the wildlife that lives in or around it. The level of eutrophication in our area in Northern California tends to increase during the late spring/early summer months, so our crew went out and took samples of Lake Chabot on June 2. We focused on the area of the lake where the water enters, known on the map as Honker Bay. We also took readings a ways down in deeper water for comparison's sake. Visually, the lake looked in bad shape. The water was a murky green that glimmered with particulate matter that swirled around the boat as we went by. In the Honker Bay region where we focused our testing, there were reeds bathed in algae that coated the surface of the lake in thick, swirling patterns. Surprisingly enough, however, our test results didn't reveal any extreme levels of phosphorous or nitrogen. They were slightly higher than usual, but not by any significant amount. The levels we found were high enough to stimulate plant and algae growth and promote eutrophication, but not enough to do any severe damage. After a briefing with a

33 CFR 162.134 - Connecting waters from Lake Huron to Lake Erie; traffic rules.

Science.gov (United States)

2010-07-01

... 33 Navigation and Navigable Waters 2 2010-07-01 2010-07-01 false Connecting waters from Lake Huron to Lake Erie; traffic rules. 162.134 Section 162.134 Navigation and Navigable Waters COAST GUARD... REGULATIONS § 162.134 Connecting waters from Lake Huron to Lake Erie; traffic rules. (a) Detroit River. The...

33 CFR 162.138 - Connecting waters from Lake Huron to Lake Erie; speed rules.

Science.gov (United States)

2010-07-01

... 33 Navigation and Navigable Waters 2 2010-07-01 2010-07-01 false Connecting waters from Lake Huron to Lake Erie; speed rules. 162.138 Section 162.138 Navigation and Navigable Waters COAST GUARD... REGULATIONS § 162.138 Connecting waters from Lake Huron to Lake Erie; speed rules. (a) Maximum speed limit for...

33 CFR 162.136 - Connecting waters from Lake Huron to Lake Erie; anchorage grounds.

Science.gov (United States)

2010-07-01

... 33 Navigation and Navigable Waters 2 2010-07-01 2010-07-01 false Connecting waters from Lake Huron to Lake Erie; anchorage grounds. 162.136 Section 162.136 Navigation and Navigable Waters COAST GUARD... REGULATIONS § 162.136 Connecting waters from Lake Huron to Lake Erie; anchorage grounds. (a) In the Detroit...

Limnology of Sawtooth Valley Lakes in 1995

Energy Technology Data Exchange (ETDEWEB)

Luecke, C.; Slater, M.; Budy, P.

1996-05-01

Included in this section of the report on limnology of Lakes in the Snake River Plain are descriptions of the limnological characteristics of the four lakes in reference to their potential effect of growth and survival of juvenile sockeye salmon. Physical parameters included light penetration, Secchi transparency, and water temperature; chemical parameters included oxygen, and both dissolved and particulate forms of nitrogen and phosphorus. Phytoplankton parameters included chlorophyll concentration, biovolume of dominant taxa, and rates of primary production; zooplankton parameters included density and biomass estimate, length frequencies, and the number of eggs carried by female cladocerans. 11 figs., 5 tabs.

Limnology of Sawtooth Valley Lakes in 1995

International Nuclear Information System (INIS)

Luecke, C.; Slater, M.; Budy, P.

1996-01-01

Included in this section of the report on limnology of Lakes in the Snake River Plain are descriptions of the limnological characteristics of the four lakes in reference to their potential effect of growth and survival of juvenile sockeye salmon. Physical parameters included light penetration, Secchi transparency, and water temperature; chemical parameters included oxygen, and both dissolved and particulate forms of nitrogen and phosphorus. Phytoplankton parameters included chlorophyll concentration, biovolume of dominant taxa, and rates of primary production; zooplankton parameters included density and biomass estimate, length frequencies, and the number of eggs carried by female cladocerans. 11 figs., 5 tabs

Lake Austin uranium deposit, Western Australia

International Nuclear Information System (INIS)

Heath, A.G.; Deutscher, R.L.; Butt, C.R.M.

1984-01-01

The Lake Austin uranium deposit is a calcrete type deposit in the Yilgarn Block, near Cue, in a catchment area of granitoids and greenstones. The uranium is in valley fill and the sediments of the Lake Austin playa. The mineralization occurs over 1 to 6 meter thickness close to the water table in calcrete overlying clays and/or weathered bedrock. The principal uranium mineral is carnotite. Waters in nearby channels have an uranium content of over 30 ppb. The chloride content of the water increases downstream in the nearby drainages, as does the uranium and vanadium content. (author)

Hydraulic, geomorphic, and trout habitat conditions of the Lake Fork of the Gunnison River in Hinsdale County, Lake City, Colorado, Water Years 2010-2011

Science.gov (United States)

Williams, Cory A.; Richards, Rodney J.; Schaffrath, Keelin R.

2015-01-01

Channel rehabilitation, or reconfiguration, to mitigate a variety of riverine problems has become a common practice in the western United States. However, additional work to monitor and assess the channel response to, and the effectiveness of, these modifications over longer periods of time (decadal or longer) is still needed. The Lake Fork of the Gunnison River has been an area of active channel modification to accommodate the needs of the Lake City community since the 1950s. The Lake Fork Valley Conservancy District began a planning process to assess restoration options for a reach of the Lake Fork in Lake City to enhance hydraulic and ecologic characteristics of the reach. Geomorphic channel form is affected by land-use changes within the basin and geologic controls within the reach. The historic channel was defined as a dynamic, braided channel with an active flood plain. This can result in a natural tendency for the channel to braid. A braided channel can affect channel stability of reconfigured reaches when a single-thread meandering channel is imposed on the stream. The U.S. Geological Survey, in cooperation with the Colorado Water Conservation Board and Colorado River Water Conservation District, began a study in 2010 to quantify existing hydraulic and habitat conditions for a reach of the Lake Fork of the Gunnison River in Lake City, Colorado. The purpose of this report is to quantify existing Lake Fork hydraulic and habitat conditions and establish a baseline against which post-reconfiguration conditions can be compared. This report (1) quantifies the existing hydraulic and geomorphic conditions in a 1.1-kilometer section of the Lake Fork at Lake City that has been proposed as a location for future channel-rehabilitation efforts, (2) characterizes the habitat suitability of the reach for two trout species based on physical conditions within the stream, and (3) characterizes the current riparian canopy density.

Water quality management for Lake Mariout

Directory of Open Access Journals (Sweden)

N. Donia

2016-06-01

Full Text Available A hydrodynamic and water quality model was used to study the current status of the Lake Mariout subject to the pollution loadings from the agricultural drains and the point sources discharging directly to the Lake. The basic water quality modelling component simulates the main water quality parameters including the oxygen compounds (BOD, COD, DO, nutrients compounds (NH4, TN, TP, and finally the temperature, salinity and inorganic matter. Many scenarios have been conducted to improve the circulation and the water quality in the lake and to assess the spreading and mixing of the discharge effluents and its impact on the water quality of the main basin. Several pilot interventions were applied through the model in the Lake Mariout together with the upgrades of the East and West Waste Water Treatment Plants in order to achieve at least 5% reduction in the pollution loads entering the Mediterranean Sea through Lake Mariout in order to improve the institutional mechanisms for sustainable coastal zone management in Alexandria in particular to reduce land-based pollution to the Mediterranean Sea.

Documentation of the Santa Clara Valley regional ground-water/surface-water flow model, Santa Clara Valley, California

Science.gov (United States)

Hanson, R.T.; Li, Zhen; Faunt, C.C.

2004-01-01

The Santa Clara Valley is a long, narrow trough extending about 35 miles southeast from the southern end of San Francisco Bay where the regional alluvial-aquifer system has been a major source of water. Intensive agricultural and urban development throughout the 20th century and related ground-water development resulted in ground-water-level declines of more than 200 feet and land subsidence of as much as 12.7 feet between the early 1900s and the mid-1960s. Since the 1960s, Santa Clara Valley Water District has imported surface water to meet growing demands and reduce dependence on ground-water supplies. This importation of water has resulted in a sustained recovery of the ground-water flow system. To help support effective management of the ground-water resources, a regional ground-water/surface-water flow model was developed. This model simulates the flow of ground water and surface water, changes in ground-water storage, and related effects such as land subsidence. A numerical ground-water/surface-water flow model of the Santa Clara Valley subbasin of the Santa Clara Valley was developed as part of a cooperative investigation with the Santa Clara Valley Water District. The model better defines the geohydrologic framework of the regional flow system and better delineates the supply and demand components that affect the inflows to and outflows from the regional ground-water flow system. Development of the model includes revisions to the previous ground-water flow model that upgraded the temporal and spatial discretization, added source-specific inflows and outflows, simulated additional flow features such as land subsidence and multi-aquifer wellbore flow, and extended the period of simulation through September 1999. The transient-state model was calibrated to historical surface-water and ground-water data for the period 197099 and to historical subsidence for the period 198399. The regional ground-water flow system consists of multiple aquifers that are grouped

California's Central Valley Groundwater Study: A Powerful New Tool to Assess Water Resources in California's Central Valley

Science.gov (United States)

Faunt, Claudia C.; Hanson, Randall T.; Belitz, Kenneth; Rogers, Laurel

2009-01-01

Competition for water resources is growing throughout California, particularly in the Central Valley. Since 1980, the Central Valley's population has nearly doubled to 3.8 million people. It is expected to increase to 6 million by 2020. Statewide population growth, anticipated reductions in Colorado River water deliveries, drought, and the ecological crisis in the Sacramento-San Joaquin Delta have created an intense demand for water. Tools and information can be used to help manage the Central Valley aquifer system, an important State and national resource.

Understanding the behavior of carbon dioxide and surface energy fluxes in semiarid Salt Lake Valley, Utah, USA

Science.gov (United States)

Ramamurthy, Prathap

This dissertation reports the findings from the Salt Lake Valley flux study. The Salt Lake Valley flux study was designed to improve our understanding of the complex land-atmosphere interactions in urban areas. The flux study used the eddy covariance technique to quantify carbon dioxide and surface energy budget in the semiarid Salt Lake Valley. Apart from quantifying fluxes, the study has also added new insight into the nature of turbulent scalar transport in urban areas and has addressed some of the complications in using Eddy Covariance technique in urban areas. As part of this experiment, eddy fluxes of CO2 and surface energy fluxes were measured at two sites, with distinct urban landforms; One site was located in a suburban neighborhood with substantial vegetative cover, prototypical of many residential neighborhoods in the valley. The other CO2 site was in a preurban surrounding that resembled the Salt Lake Valley before it was urbanized. The two sites were intentionally chosen to illustrate the impact of urbanization on CO 2 and surface energy flux cycles. Results indicate that the suburban site acted as a sink of CO2 during the midday period due to photosynthesis and acted as a source of CO2 during the evening and nighttime periods. The vegetative cover around the suburban site also had a significant impact on the surface energy fluxes. Contribution from latent heat flux was substantially high at the suburban site during the summer months compared to sensible heat. The turbulence investigation found that the general behavior of turbulence was very much influenced by local factors and the statistics did not always obey Monin-Obukhov Similarity parameters. This investigation also found that the scalar (co)spectra observed at the suburban site were characterized by multiple peaks and were different compared to (co)spectra reported over forest and crop canopies. The study also observed multiscale CO2 transport at the suburban site during the convective period

Response of the St. Joseph River to lake level changes during the last 12,000 years in the Lake Michigan basin

Science.gov (United States)

Kincare, K.A.

2007-01-01

The water level of the Lake Michigan basin is currently 177 m above sea level. Around 9,800 14C years B.P., the lake level in the Lake Michigan basin had dropped to its lowest level in prehistory, about 70 m above sea level. This low level (Lake Chippewa) had profound effects on the rivers flowing directly into the basin. Recent studies of the St. Joseph River indicate that the extreme low lake level rejuvenated the river, causing massive incision of up to 43 m in a valley no more than 1.6 km wide. The incision is seen 25 km upstream of the present shoreline. As lake level rose from the Chippewa low, the St. Joseph River lost competence and its estuary migrated back upstream. Floodplain and channel sediments partially refilled the recently excavated valley leaving a distinctly non-classical morphology of steep sides with a broad, flat bottom. The valley walls of the lower St. Joseph River are 12-18 m tall and borings reveal up to 30 m of infill sediment below the modern floodplain. About 3 ?? 108 m3 of sediment was removed from the St. Joseph River valley during the Chippewa phase lowstand, a massive volume, some of which likely resides in a lowstand delta approximately 30 km off-shore in Lake Michigan. The active floodplain below Niles, Michigan, is inset into an upper terrace and delta graded to the Calumet level (189 m) of Lake Chicago. In the lower portion of the terrace stratigraphy a 1.5-2.0 m thick section of clast-supported gravel marks the entry of the main St. Joseph River drainage above South Bend, Indiana, into the Lake Michigan basin. This gravel layer represents the consolidation of drainage that probably occurred during final melting out of ice-marginal kettle chains allowing stream piracy to proceed between Niles and South Bend. It is unlikely that the St. Joseph River is palimpsest upon a bedrock valley. The landform it cuts across is a glaciofluvial-deltaic feature rather than a classic unsorted moraine that would drape over pre-glacial topography

Floodplain lakes and alluviation cycles of the lower Colorado River

Science.gov (United States)

Malmon, D.; Felger, T. J.; Howard, K. A.

2007-05-01

The broad valleys along the lower Colorado River contain numerous bodies of still water that provide critical habitat for bird, fish, and other species. This chain of floodplain lakes is an important part of the Pacific Flyway - the major north-south route of travel for migratory birds in the western Hemisphere - and is also used by many resident bird species. In addition, isolated floodplain lakes may provide the only viable habitat for endangered native fish such as the razorback sucker, vulnerable to predation by introduced species in the main stem of the Colorado River. Floodplain lakes typically occupy former channel courses of the river and formed as a result of river meandering or avulsion. Persistent fluvial sediment deposition (aggradation) creates conditions that favor rapid formation and destruction of floodplain lakes, while long term river downcutting (degradation) inhibits their formation and evolution. New radiocarbon dates from wood recovered from drill cores near Topock, AZ indicate that the river aggraded an average of 3 mm/yr in the middle and late Holocene. Aggradational conditions before Hoover Dam was built were associated with rapid channel shifting and frequent lake formation. Lakes had short life spans due to rapid infilling with fine-grained sediment during turbid floods on the unregulated Colorado River. The building of dams and of armored banks had a major impact on floodplain lakes, not only by drowning large portions of the valley beneath reservoirs, but by preventing new lake formation in some areas and accelerating it in others. GIS analyses of three sets of historical maps show that both the number and total area of isolated (i.e., not linked to the main channel by a surface water connection) lakes in the lower Colorado River valley increased between 1902 and the 1950s, and then decreased though the 1970s. River bed degradation below dams inhibits channel shifting and floodplain lake formation, and the capture of fines behind the

Is drinking water from 'improved sources' really safe? A case study in the Logone valley (Chad-Cameroon).

Science.gov (United States)

Sorlini, S; Palazzini, D; Mbawala, A; Ngassoum, M B; Collivignarelli, M C

2013-12-01

Within a cooperation project coordinated by the Association for Rural Cooperation in Africa and Latin America (ACRA) Foundation, water supplies were sampled across the villages of the Logone valley (Chad-Cameroon) mostly from boreholes, open wells, rivers and lakes as well as from some piped water. Microbiological analyses and sanitary inspections were carried out at each source. The microbiological quality was determined by analysis of indicators of faecal contamination, Escherichia coli, Enterococci and Salmonellae, using the membrane filtration method. Sanitary inspections were done using WHO query forms. The assessment confirmed that there are several parameters of health concern in the studied area; bacteria of faecal origins are the most significant. Furthermore, this study demonstrated that Joint Monitoring Programme (JMP) classification and E. coli measurement are not sufficient to state water safety. In fact, in the studied area, JMP defined 'improved sources' may provide unsafe water depending on their structure and sources without E. coli may have Enterococci and Salmonellae. Sanitary inspections also revealed high health risks for some boreholes. In other cases, sources with low sanitary risk and no E. coli were contaminated by Enterococci and Salmonellae. Better management and protection of the sources, hygiene improvement and domestic water treatment before consumption are possible solutions to reduce health risks in the Logone valley.

Lake Chini Water Quality Assessment Using Multivariate Approach

International Nuclear Information System (INIS)

Ahmad, A.K.; Shuhaimi, Othman M.; Lim, E.C.; Aziz, Z.A.

2013-01-01

An analysis was undertaken using the multivariate approach to determine the important water quality for shallow lake water quality assessment. Fourteen water quality parameters which includes biological, physical and chemical components were collected monthly over twelve month period. The data were analysed using factor analysis which involves identification of factor correlation, factor extraction and factor permutations. The first process involved the clustering of high correlation parameters into its respective factor and the removal of parameters that have more than one factor. Agglomerative hierarchy (HACA) and discriminant analysis (DA) were also used to exhibit the important factors that has significant influence on lake water quality. The analysis showed that Lake Chini water quality was determined by more than one factor. The results indicated that the biological and chemical (nutrients) components have significant influence in determining the lake water quality. The biological parameters namely BOD5, COD, chlorophyll a and chemical (nitrate and orthophosphate) are important parameters in Lake Chini. All analysis demonstrated the importance of biological and chemical water quality components in the determination of Lake Chini water quality. (author)

Evaluate prevailing climate change on Great Lakes water levels

International Nuclear Information System (INIS)

Islam, M.

2009-01-01

'Full text:'In this paper, results of a comprehensive water mass balance modeling for the Great Lakes against prevailing and different anticipated climate change scenarios would be presented. Modeling is done in evaluating the changes in the lake storages and then changes in the lake's water level considering present condition, uncertainty and variability of climate and hydrologic conditions in the future. Inflow-outflow and consequent changes in the five Great Lake's storages are simulated for the last 30 years and then projected to evaluate the changes in the lake storages for the next 50 years. From the predicted changes in the lake storage data, water level is calculated using mass to linear conversion equation. Modeling and analysis results are expected to be helpful in understanding the possible impacts of the climate change on the Great Lakes water environment and preparing strategic plan for the sustainable management of lake's water resources. From the recent past, it is observed that there is a depleting trend in the lakes water level and hence there is a potential threat to lake's water environment and uncertainty of the availability of quality and quantity of water for the future generations, especially against prevailing and anticipated climate changes. For this reason, it is an urgent issue of understanding and quantifying the potential impacts of climate change on the Great Lake's water levels and storages. (author)

Energy and water in the Great Lakes.

Energy Technology Data Exchange (ETDEWEB)

Tidwell, Vincent Carroll

2011-11-01

The nexus between thermoelectric power production and water use is not uniform across the U.S., but rather differs according to regional physiography, demography, power plant fleet composition, and the transmission network. That is, in some regions water demand for thermoelectric production is relatively small while in other regions it represents the dominate use. The later is the case for the Great Lakes region, which has important implications for the water resources and aquatic ecology of the Great Lakes watershed. This is today, but what about the future? Projected demographic trends, shifting lifestyles, and economic growth coupled with the threat of global climate change and mounting pressure for greater U.S. energy security could have profound effects on the region's energy future. Planning for such an uncertain future is further complicated by the fact that energy and environmental planning and regulatory decisionmaking is largely bifurcated in the region, with environmental and water resource concerns generally taken into account after new energy facilities and technologies have been proposed, or practices are already in place. Based on these confounding needs, the objective of this effort is to develop Great Lakes-specific methods and tools to integrate energy and water resource planning and thereby support the dual goals of smarter energy planning and development, and protection of Great Lakes water resources. Guiding policies for this planning are the Great Lakes and St. Lawrence River Basin Water Resources Compact and the Great Lakes Water Quality Agreement. The desired outcome of integrated energy-water-aquatic resource planning is a more sustainable regional energy mix for the Great Lakes basin ecosystem.

Establishment patterns of water-elm at Catahoula Lake, Louisiana

Science.gov (United States)

Karen S. Doerr; Sanjeev Joshi; Richard F. Keim

2015-01-01

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...

Characterizing Microbial Mat Morphology with Structure from Motion Techniques in Ice-Covered Lake Joyce, McMurdo Dry Valleys, Antarctica

Science.gov (United States)

Mackey, T. J.; Leidman, S. Z.; Allen, B.; Hawes, I.; Lawrence, J.; Jungblut, A. D.; Krusor, M.; Coleman, L.; Sumner, D. Y.

2015-12-01

Structure from Motion (SFM) techniques can provide quantitative morphological documentation of otherwise inaccessible benthic ecosystems such as microbial mats in Lake Joyce, a perennially ice-covered lake of the Antarctic McMurdo Dry Valleys (MDV). Microbial mats are a key ecosystem of MDV lakes, and diverse mat morphologies like pinnacles emerge from interactions among microbial behavior, mineralization, and environmental conditions. Environmental gradients can be isolated to test mat growth models, but assessment of mat morphology along these gradients is complicated by their inaccessibility: the Lake Joyce ice cover is 4-5 m thick, water depths containing diverse pinnacle morphologies are 9-14 m, and relevant mat features are cm-scale. In order to map mat pinnacle morphology in different sedimentary settings, we deployed drop cameras (SeaViewer and GoPro) through 29 GPS referenced drill holes clustered into six stations along a transect spanning 880 m. Once under the ice cover, a boom containing a second GoPro camera was unfurled and rotated to collect oblique images of the benthic mats within dm of the mat-water interface. This setup allowed imaging from all sides over a ~1.5 m diameter area of the lake bottom. Underwater lens parameters were determined for each camera in Agisoft Lens; images were reconstructed and oriented in space with the SFM software Agisoft Photoscan, using the drop camera axis of rotation as up. The reconstructions were compared to downward facing images to assess accuracy, and similar images of an object with known geometry provided a test for expected error in reconstructions. Downward facing images identify decreasing pinnacle abundance in higher sedimentation settings, and quantitative measurements of 3D reconstructions in KeckCAVES LidarViewer supplement these mat morphological facies with measurements of pinnacle height and orientation. Reconstructions also help isolate confounding variables for mat facies trends with measurements

A 28,000 year history of vegetation and climate from Lower Red Rock Lake, Centennial Valley, Southwestern Montana, USA

Science.gov (United States)

Mumma, Stephanie Ann; Whitlock, Cathy; Pierce, Kenneth

2012-01-01

A sediment core extending to 28,000 cal yr BP from Lower Red Rock Lake in the Centennial Valley of southwestern Montana provides new information on the nature of full-glacial vegetation as well as a history of late-glacial and Holocene vegetation and climate in a poorly studied region. Prior to 17,000 cal yr BP, the eastern Centennial Valley was occupied by a large lake (Pleistocene Lake Centennial), and valley glaciers were present in adjacent mountain ranges. The lake lowered upon erosion of a newly formed western outlet in late-glacial time. High pollen percentages of Juniperus, Poaceae, Asteraceae, and other herbs as well as low pollen accumulation rates suggest sparse vegetation cover. Inferred cold dry conditions are consistent with a strengthened glacial anticyclone at this time. Between 17,000 and 10,500 cal yr BP, high Picea and Abies pollen percentages suggest a shift to subalpine parkland and warmer conditions than before. This is attributed to the northward shift of the jet stream and increasing summer insolation. From 10,500 to 7100 cal yr BP, pollen evidence of open dry forests suggests warm conditions, which were likely a response to increased summer insolation and a strengthened Pacific subtropical high-pressure system. From 7100 to 2400 cal yr BP, cooler moister conditions promoted closed forest and wetlands. Increases in Picea and Abies pollen percentages after 2400 cal yr BP suggest increasing effective moisture. The postglacial pattern of Pseudotsuga expansion indicates that it arrived later on the Atlantic side of the Continental Divide than on the Pacific side. The Divide may have been a physical barrier for refugial populations or it delimited different climate regions that influenced the timing of Pseudotsuga expansion.

78 FR 21414 - Central Valley Project Improvement Act, Water Management Plans

Science.gov (United States)

2013-04-10

... Valley Project Improvement Act, Water Management Plans AGENCY: Bureau of Reclamation, Interior. ACTION: Notice of availability. SUMMARY: The following Water Management Plans are available for review... establish and administer an office on Central Valley Project water conservation best management practices...

Evaluation of Water Security in Kathmandu Valley before and after Water Transfer from another Basin

OpenAIRE

Bhesh Raj Thapa; Hiroshi Ishidaira; Vishnu Prasad Pandey; Tilak Mohan Bhandari; Narendra Man Shakya

2018-01-01

Kathmandu Upatyaka Khanepani Limited (KUKL) has planned to harness water from outside the valley from Melamchi as an inter-basin project to supply water inside the ring road (core valley area) of the Kathmandu Valley (KV). The project, called the “Melamchi Water Supply Project (MWSP)”, is expected to have its first phase completed by the end of September 2018 and its second phase completed by the end of 2023 to supply 170 MLD (million liters a day) through the first phase and an additional 34...

Mercury in fish from three rift valley lakes (Turkana, Naivasha and Baringo), Kenya, East Africa

Energy Technology Data Exchange (ETDEWEB)

Campbell, L.M.; Osano, O.; Hecky, R.E.; Dixon, D.G

2003-09-01

Mercury concentrations in Kenyan fish vary with tropic position but, in general, do not pose an unacceptable risk to human consumers of wildlife. -Total mercury (THg) concentrations were measured for various fish species from Lakes Turkana, Naivasha and Baringo in the rift valley of Kenya. The highest THg concentration (636 ng g{sup -1} wet weight) was measured for a piscivorous tigerfish Hydrocynus forskahlii from Lake Turkana. THg concentrations for the Perciformes species, the Nile perch Lates niloticus from Lake Turkana and the largemouth bass Micropterus salmoides from Lake Naivasha ranged between 4 and 95 ng g{sup -1}. The tilapiine species in all lakes, including the Nile tilapia Oreochromis niloticus, had consistently low THg concentrations ranging between 2 and 25 ng g{sup -1}. In Lake Naivasha, the crayfish species, Procambrus clarkii, had THg concentrations similar to those for the tilapiine species from the same lake, which is consistent with their shared detritivore diet. THg concentrations in all fish species were usually consistent with their known trophic position, with highest concentrations in piscivores and declining in omnivores, insectivores and detritivores. One exception is the detritivore Labeo cylindricus from Lake Baringo, which had surprisingly elevated THg concentrations (mean=75 ng g{sup -1}), which was similar to those for the top trophic species (Clarias and Protopterus) in the same lake. Except for two Hydrocynus forskahlii individuals from Lake Turkana, which had THg concentrations near or above the international marketing limit of 500 ng g{sup -1}, THg concentrations in the fish were generally below those of World Health Organization's recommended limit of 200 ng g{sup -1} for at-risk groups.

Evaluation of ground-water flow and hydrologic budget for Lake Five-O, a seepage lake in northwestern Florida

Science.gov (United States)

Grubbs, J.W.

1995-01-01

Temporal and spatial distributions of ground-water inflow to, and leakage from Lake Five-O, a softwater, seepage lake in northwestern Florida, were evaluated using hydrologic data and simulation models of the shallow ground-water system adjacent to the lake. The simulation models indicate that ground-water inflow to the lake and leakage from the lake to the ground-water system are the dominant components in the total inflow (precipitation plus ground-water inflow) and total outflow (evaporation plus leakage) budgets of Lake Five-O. Simlulated ground-water inflow and leakage were approximately 4 and 5 times larger than precipitation inputs and evaporative losses, respectively, during calendar years 1989-90. Exchanges of water between Lake Five-O and the ground-water system were consistently larger than atmospheric-lake exchanges. A consistent pattern of shallow ground-water inflow and deep leakage was also evident throughout the study period. The mean time of travel from ground-water that discharges at Lake Five-O (time from recharge at the water table to discharge at the lake) was estimated to be within a range of 3 to 6 years. Flow-path evaluations indicated that the intermediate confining unit probably has a negligible influence on the geochemistry of ground-water inflow to Lake Five-O. The hydrologic budgets and flow-path evaluations provide critical information for developing geochemical budgets for Lake Five-O and for improving the understanding of the relative importance of various processes that regulate the acid-neutralizing capacity of softwater seepage lakes in Florida.

Long-Term Variability of Satellite Lake Surface Water Temperatures in the Great Lakes

Science.gov (United States)

Gierach, M. M.; Matsumoto, K.; Holt, B.; McKinney, P. J.; Tokos, K.

2014-12-01

The Great Lakes are the largest group of freshwater lakes on Earth that approximately 37 million people depend upon for fresh drinking water, food, flood and drought mitigation, and natural resources that support industry, jobs, shipping and tourism. Recent reports have stated (e.g., the National Climate Assessment) that climate change can impact and exacerbate a range of risks to the Great Lakes, including changes in the range and distribution of certain fish species, increased invasive species and harmful algal blooms, declining beach health, and lengthened commercial navigation season. In this study, we will examine the impact of climate change on the Laurentian Great Lakes through investigation of long-term lake surface water temperatures (LSWT). We will use the ATSR Reprocessing for Climate: Lake Surface Water Temperature & Ice Cover (ARC-Lake) product over the period 1995-2012 to investigate individual and interlake variability. Specifically, we will quantify the seasonal amplitude of LSWTs, the first and last appearances of the 4°C isotherm (i.e., an important identifier of the seasonal evolution of the lakes denoting winter and summer stratification), and interpret these quantities in the context of global interannual climate variability such as ENSO.

Water pollution control technology and strategy for river-lake systems: a case study in Gehu Lake and Taige Canal.

Science.gov (United States)

Zhang, Yimin; Zhang, Yongchun; Gao, Yuexiang; Zhang, Houhu; Cao, Jianying; Cai, Jinbang; Kong, Xiangji

2011-07-01

The Taoge water system is located in the upstream of Taihu Lake basin and is characterized by its multi-connected rivers and lakes. In this paper, current analyses of hydrology, hydrodynamics and water pollution of Gehu Lake and Taige Canal are presented. Several technologies are proposed for pollution prevention and control, and water environmental protection in the Taihu Lake basin. These included water pollution control integration technology for the water systems of Gehu Lake, Taige Canal and Caoqiao River. Additionally, river-lake water quality and quantity regulation technology, ecological restoration technology for polluted and degraded water bodies, and water environmental integration management and optimization strategies were also examined. The main objectives of these strategies are to: (a) improve environmental quality of relative water bodies, prevent pollutants from entering Gehu Lake and Taige Canal, and ensure that the clean water after the pre-treatment through Gehu Lake is not polluted before entering the Taihu Lake through Taige Canal; (b) stably and efficiently intercept and decrease the pollution load entering the lake through enhancing the river outlet ecological system structure function and water self-purifying capacity, and (c) designate Gehu Lake as a regulation system for water quality and water quantity in the Taoge water system and thus guarantee the improvement of the water quality of the inflow into Taihu Lake.

Stable isotopic composition of East African lake waters

International Nuclear Information System (INIS)

Odada, E.O.

2001-01-01

The investigation of stable isotopic composition of East African lake waters was conducted by scientists from the Department of Geology, University of Nairobi, as part of the International Decade for the East African Lakes (IDEAL) project and in close collaboration with the scientists from Large Lakes Observatory of the University of Minnesota and the Isotope Hydrology Laboratory of the IAEA in Vienna. The Research Contract was part of the IAEA Co-ordinated Research Programme on Isotope Techniques in Lake Dynamics Investigations, and was sponsored by the Agency. Water and grab sediment samples were obtained from East African Lakes during the month of January and February 1994 and July/August 1995. Water samples were analysed for oxygen and deuterium isotopic composition at the IAEA Laboratories in Vienna, Austria. In this final paper we report the results of the study of oxygen and deuterium isotopic composition from the East African lake waters. (author)

Deep lake water cooling a renewable technology

Energy Technology Data Exchange (ETDEWEB)

Eliadis, C.

2003-06-01

In the face of increasing electrical demand for air conditioning, the damage to the ozone layer by CFCs used in conventional chillers, and efforts to reduce the greenhouse gases emitted into the atmosphere by coal-fired power generating stations more and more attention is focused on developing alternative strategies for sustainable energy. This article describes one such strategy, namely deep lake water cooling, of which the Enwave project recently completed on the north shore of Lake Ontario is a prime example. The Enwave Deep Lake Water Cooling (DLWC) project is a joint undertaking by Enwave and the City of Toronto. The $180 million project is unique in design and concept, using the coldness of the lake water from the depths of Lake Ontario (not the water itself) to provide environmentally friendly air conditioning to office towers. Concurrently, the system also provides improved quality raw cold water to the city's potable water supply. The plant has a rated capacity of 52,200 tons of refrigeration. The DLWC project is estimated to save 75-90 per cent of the electricity that would have been generated by a coal-fired power station. Enwave, established over 20 years ago, is North America's largest district energy system, delivering steam, hot water and chilled water to buildings from a central plant via an underground piping distribution network. 2 figs.

Perchlorate in Lake Water from an Operating Diamond Mine.

Science.gov (United States)

Smith, Lianna J D; Ptacek, Carol J; Blowes, David W; Groza, Laura G; Moncur, Michael C

2015-07-07

Mining-related perchlorate [ClO4(-)] in the receiving environment was investigated at the operating open-pit and underground Diavik diamond mine, Northwest Territories, Canada. Samples were collected over four years and ClO4(-) was measured in various mine waters, the 560 km(2) ultraoligotrophic receiving lake, background lake water and snow distal from the mine. Groundwaters from the underground mine had variable ClO4(-) concentrations, up to 157 μg L(-1), and were typically an order of magnitude higher than concentrations in combined mine waters prior to treatment and discharge to the lake. Snow core samples had a mean ClO4(-) concentration of 0.021 μg L(-1) (n=16). Snow and lake water Cl(-)/ClO4(-) ratios suggest evapoconcentration was not an important process affecting lake ClO4(-) concentrations. The multiyear mean ClO4(-) concentrations in the lake were 0.30 μg L(-1) (n = 114) in open water and 0.24 μg L(-1) (n = 107) under ice, much below the Canadian drinking water guideline of 6 μg L(-1). Receiving lake concentrations of ClO4(-) generally decreased year over year and ClO4(-) was not likely [biogeo]chemically attenuated within the receiving lake. The discharge of treated mine water was shown to contribute mining-related ClO4(-) to the lake and the low concentrations after 12 years of mining were attributed to the large volume of the receiving lake.

Environmental Monitoring, Water Quality - Lakes Assessments - Attaining

Data.gov (United States)

NSGIC Education | GIS Inventory — This layer shows only attaining lakes of the Integrated List. The Lakes Integrated List represents lake assessments in an integrated format for the Clean Water Act...

Global Lakes Sentinel Services: Evaluation of Chl-a Trends in Deep Clear Lakes

Science.gov (United States)

Cazzaniga, Ilaria; Giardino, Claudia; Bresciani, Mariano; Poser, Kathrin; Peters, Steef; Hommersom, Annelies; Schenk, Karin; Heege, Thomas; Philipson, Petra; Ruescas, Ana; Bottcher, Martin; Stelzer, Kerstin

2016-08-01

The aim of this study is the analysis of trend in the trophic level evolution in clear deep lakes which, being characterised by good quality state, are important socio- economic resources for their regions. The selected lakes are situated in Europe (Garda, Maggiore, Constance and Vättern), North America (Michigan) and Africa (Malawi and Tanganyika) and cover a range of eco- regions (continental, perialpine, boreal, rift valley) distributed globally.To evaluate trophic level tendency we mainly focused on chlorophyll-a concentrations (chl-a) which is a direct proxy of trophic status. The chl-a concentrations were obtained from 5216 cloud-free MERIS imagery from 2002 to 2012.The 'GLaSS RoIStats tool' available within the GLaSS project was used to extract chl-a in a number of region of interests (ROI) located in pelagic waters as well as some few other stations depending on lakes morphology. For producing the time-series trend, these extracted data were analysed with the Seasonal Kendall test.The results overall show almost stable conditions with a slight increase in concentration for lakes Maggiore, Constance, and the Green Bay of Lake Michigan; a slight decrease for lakes Garda and Tanganyika and absolutely stable conditions for lakes Vättern and Malawi.The results presented in this work show the great capability of MERIS to perform trend tests analysis on trophic status with focus on chl-a concentration. Being chl-a also a key parameter in water quality monitoring plans, this study also supports the managing practices implemented worldwide for using the water of the lakes.

Chemodenitrification in the cryoecosystem of Lake Vida, Victoria Valley, Antarctica.

Science.gov (United States)

Ostrom, N E; Gandhi, H; Trubl, G; Murray, A E

2016-11-01

Lake Vida, in the Victoria Valley of East Antarctica, is frozen, yet harbors liquid brine (~20% salt, >6 times seawater) intercalated in the ice below 16 m. The brine has been isolated from the surface for several thousand years. The brine conditions (permanently dark, -13.4 °C, lack of O 2 , and pH of 6.2) and geochemistry are highly unusual. For example, nitrous oxide (N 2 O) is present at a concentration among the highest reported for an aquatic environment. Only a minor 17 O anomaly was observed in N 2 O, indicating that this gas was predominantly formed in the lake. In contrast, the 17 O anomaly in nitrate (NO3-) in Lake Vida brine indicates that approximately half or more of the NO3- present is derived from atmospheric deposition. Lake Vida brine was incubated in the presence of 15 N-enriched substrates for 40 days. We did not detect microbial nitrification, dissimilatory reduction of NO3- to ammonium (NH4+), anaerobic ammonium oxidation, or denitrification of N 2 O under the conditions tested. In the presence of 15 N-enriched nitrite (NO2-), both N 2 and N 2 O exhibited substantial 15 N enrichments; however, isotopic enrichment declined with time, which is unexpected. Additions of 15 N-NO2- alone and in the presence of HgCl 2 and ZnCl 2 to aged brine at -13 °C resulted in linear increases in the δ 15 N of N 2 O with time. As HgCl 2 and ZnCl 2 are effective biocides, we interpret N 2 O production in the aged brine to be the result of chemodenitrification. With this understanding, we interpret our results from the field incubations as the result of chemodenitrification stimulated by the addition of 15 N-enriched NO2- and ZnCl 2 and determined rates of N 2 O and N 2 production of 4.11-41.18 and 0.55-1.75 nmol L -1  day -1 , respectively. If these rates are representative of natural production, the current concentration of N 2 O in Lake Vida could have been reached between 6 and 465 years. Thus, chemodenitrification alone is sufficient to explain the

Isotope techniques in lake water studies

International Nuclear Information System (INIS)

Gourcy, L.

1999-01-01

Freshwater lakes are among the most easily exploitable freshwater resources. Lakes are also recognized as major sedimentological features in which stored material can be used to study recent climate and pollution evolution. To adequately preserve these important landscape features, and to use them as climatic archives, an improved understanding of processes controlling their hydrologic and bio-geochemical environments if necessary. This article briefly describes the IAEA activities related to the study of lakes in such areas as lake budget, lake dynamics, water contamination, and paleolimnological investigations

Geohydrology of Big Bear Valley, California: phase 1--geologic framework, recharge, and preliminary assessment of the source and age of groundwater

Science.gov (United States)

Flint, Lorraine E.; Brandt, Justin; Christensen, Allen H.; Flint, Alan L.; Hevesi, Joseph A.; Jachens, Robert; Kulongoski, Justin T.; Martin, Peter; Sneed, Michelle

2012-01-01

The Big Bear Valley, located in the San Bernardino Mountains of southern California, has increased in population in recent years. Most of the water supply for the area is pumped from the alluvial deposits that form the Big Bear Valley groundwater basin. This study was conducted to better understand the thickness and structure of the groundwater basin in order to estimate the quantity and distribution of natural recharge to Big Bear Valley. A gravity survey was used to estimate the thickness of the alluvial deposits that form the Big Bear Valley groundwater basin. This determined that the alluvial deposits reach a maximum thickness of 1,500 to 2,000 feet beneath the center of Big Bear Lake and the area between Big Bear and Baldwin Lakes, and decrease to less than 500 feet thick beneath the eastern end of Big Bear Lake. Interferometric Synthetic Aperture Radar (InSAR) was used to measure pumping-induced land subsidence and to locate structures, such as faults, that could affect groundwater movement. The measurements indicated small amounts of land deformation (uplift and subsidence) in the area between Big Bear Lake and Baldwin Lake, the area near the city of Big Bear Lake, and the area near Sugarloaf, California. Both the gravity and InSAR measurements indicated the possible presence of subsurface faults in subbasins between Big Bear and Baldwin Lakes, but additional data are required for confirmation. The distribution and quantity of groundwater recharge in the area were evaluated by using a regional water-balance model (Basin Characterization Model, or BCM) and a daily rainfall-runoff model (INFILv3). The BCM calculated spatially distributed potential recharge in the study area of approximately 12,700 acre-feet per year (acre-ft/yr) of potential in-place recharge and 30,800 acre-ft/yr of potential runoff. Using the assumption that only 10 percent of the runoff becomes recharge, this approach indicated there is approximately 15,800 acre-ft/yr of total recharge in

Lake Tahoe Water Quality Improvement Programs

Science.gov (United States)

Information on the Lake Tahoe watershed, EPA's protection efforts, water quality issues, effects of climate, change, Lake Tahoe Total Maximum Daily Load (TMDL), EPA-sponsored projects, and list of partner agencies.

Modeling The Evolution Of A Regional Aquifer System With The California Central Valley Groundwater-Surface Water Simulation Model (C2VSIM)

Science.gov (United States)

Brush, C. F.; Dogrul, E. C.; Kadir, T. N.; Moncrief, M. R.; Shultz, S.; Tonkin, M.; Wendell, D.

2006-12-01

The finite element application IWFM has been used to develop an integrated groundwater-surface water model for California's Central Valley, an area of ~50,000 km2, to simulate the evolution of the groundwater flow system and historical groundwater-surface water interactions on a monthly time step from October 1921 to September 2003. The Central Valley's hydrologic system changed significantly during this period. Prior to 1920, most surface water flowed unimpeded from source areas in the mountains surrounding the Central Valley through the Sacramento-San Joaquin Delta to the Pacific Ocean, and groundwater largely flowed from recharge areas on the valley rim to discharge as evapotransipration in extensive marshes along the valley's axis. Rapid agricultural development led to increases in groundwater pumping from ~0.5 km3/yr in the early 1920's to 13-18 km3/yr in the 1940's to 1970's, resulting in strong vertical head gradients, significant head declines throughout the valley, and subsidence of >0.3 m over an area of 13,000 km2. Construction of numerous dams and development of an extensive surface water delivery network after 1950 altered the surface water flow regime and reduced groundwater pumping to the current ~10 km3/yr, increasing net recharge and leading to local head gradient reversals and water level recoveries. A model calibrated to the range of historical flow regimes in the Central Valley will provide robust estimations of stream-groundwater interactions for a range of projected future scenarios. C2VSIM uses the IWFM application to simulate a 3-D finite element groundwater flow process dynamically coupled with 1-D land surface, stream flow, lake and unsaturated zone processes. The groundwater flow system is represented with three layers each having 1393 elements. Land surface processes are simulated using 21 subregions corresponding to California DWR water-supply planning areas. The surface-water network is simulated using 431 stream nodes representing 72

75 FR 70020 - Central Valley Project Improvement Act, Water Management Plans

Science.gov (United States)

2010-11-16

... office on Central Valley Project water conservation best management practices that shall ``* * * develop... DEPARTMENT OF THE INTERIOR Bureau of Reclamation Central Valley Project Improvement Act, Water Management Plans AGENCY: Bureau of Reclamation, Interior ACTION: Notice of Availability. SUMMARY: The...

76 FR 12756 - Central Valley Project Improvement Act, Water Management Plans

Science.gov (United States)

2011-03-08

... office on Central Valley Project water conservation best management practices that shall ``* * * develop... DEPARTMENT OF THE INTERIOR Bureau of Reclamation Central Valley Project Improvement Act, Water Management Plans AGENCY: Bureau of Reclamation, Interior. ACTION: Notice of availability. SUMMARY: The...

77 FR 64544 - Central Valley Project Improvement Act, Water Management Plans

Science.gov (United States)

2012-10-22

... Central Valley Project water conservation best management practices that shall ``develop criteria for... DEPARTMENT OF THE INTERIOR Bureau of Reclamation Central Valley Project Improvement Act, Water Management Plans AGENCY: Bureau of Reclamation, Interior. ACTION: Notice of availability. SUMMARY: The...

Eutrophication of Lake Waters in China: Cost, Causes, and Control

Science.gov (United States)

Le, C.; Zha, Y.; Li, Y.; Sun, D.; Lu, H.; Yin, B.

2010-04-01

Lake water eutrophication has become one of the most important factors impeding sustainable economic development in China. Knowledge of the current status of lake water eutrophicatoin and determination of its mechanism are prerequisites to devising a sound solution to the problem. Based on reviewing the literature, this paper elaborates on the evolutional process and current state of shallow inland lake water eutrophication in China. The mechanism of lake water eutrophication is explored from nutrient sources. In light of the identified mechanism strategies are proposed to control and tackle lake water eutrophication. This review reveals that water eutrophication in most lakes was initiated in the 1980s when the national economy underwent rapid development. At present, the problem of water eutrophication is still serious, with frequent occurrence of damaging algal blooms, which have disrupted the normal supply of drinking water in shore cities. Each destructive bloom caused a direct economic loss valued at billions of yuan. Nonpoint pollution sources, namely, waste discharge from agricultural fields and nutrients released from floor deposits, are identified as the two major sources of nitrogen and phosphorus. Therefore, all control and rehabilitation measures of lake water eutrophication should target these nutrient sources. Biological measures are recommended to rehabilitate eutrophied lake waters and restore the lake ecosystem in order to bring the problem under control.

Water balance and irrigation water pumping of Lake Merdada for potato farming in Dieng Highland, Indonesia.

Science.gov (United States)

Fadlillah, Lintang N; Widyastuti, M

2016-08-01

Lakes provide water resources for domestic use, livestock, irrigational use, etc. Water availability of lakes can be estimated using lake water balance. Lake water balance is calculated from the water input and output of a lake. Dieng Highland has several volcanic lakes in its surroundings. Lake Merdada in Dieng Highland has been experiencing extensive water pumping for several years more than other lakes in the surrounding area. It provides irrigation water for potato farming in Dieng Highland. The hydrological model of this lake has not been studied. The modeled water balance in this research uses primary data, i.e., bathymetric data, soil texture, and outflow discharge, as well as secondary data, i.e., rainfall, temperature, Landsat 7 ETM+ band 8 image, and land use. Water balance input components consist of precipitation on the surface area, surface (direct) runoff from the catchment area, and groundwater inflow and outflow (G net), while the output components consist of evaporation, river outflow, and irrigation. It shows that groundwater is the dominant input and output of the lake. On the other hand, the actual irrigation water pumping plays the leading role as human-induced alteration of outflow discharge. The maximum irrigation pumping modeling shows that it will decrease lake storage up to 37.14 % per month and may affect the ecosystem inside the lake.

Hydrology and water quality of Shell Lake, Washburn County, Wisconsin, with special emphasis on the effects of diversion and changes in water level on the water quality of a shallow terminal lake

Science.gov (United States)

Juckem, Paul F.; Robertson, Dale M.

2013-01-01

Shell Lake is a relatively shallow terminal lake (tributaries but no outlets) in northwestern Wisconsin that has experienced approximately 10 feet (ft) of water-level fluctuation over more than 70 years of record and extensive flooding of nearshore areas starting in the early 2000s. The City of Shell Lake (City) received a permit from the Wisconsin Department of Natural Resources in 2002 to divert water from the lake to a nearby river in order to lower water levels and reduce flooding. Previous studies suggested that water-level fluctuations were driven by long-term cycles in precipitation, evaporation, and runoff, although questions about the lake’s connection with the groundwater system remained. The permit required that the City evaluate assumptions about lake/groundwater interactions made in previous studies and evaluate the effects of the water diversion on water levels in Shell Lake and other nearby lakes. Therefore, a cooperative study between the City and U.S. Geological Survey (USGS) was initiated to improve the understanding of the hydrogeology of the area and evaluate potential effects of the diversion on water levels in Shell Lake, the surrounding groundwater system, and nearby lakes. Concerns over deteriorating water quality in the lake, possibly associated with changes in water level, prompted an additional cooperative project between the City and the USGS to evaluate efeffects of changes in nutrient loading associated with changes in water levels on the water quality of Shell Lake. Numerical models were used to evaluate how the hydrology and water quality responded to diversion of water from the lake and historical changes in the watershed. The groundwater-flow model MODFLOW was used to simulate groundwater movement in the area around Shell Lake, including groundwater/surface-water interactions. Simulated results from the MODFLOW model indicate that groundwater flows generally northward in the area around Shell Lake, with flow locally converging

76 FR 54251 - Central Valley Project Improvement Act, Water Management Plans

Science.gov (United States)

2011-08-31

... and administer an office on Central Valley Project water conservation best management practices that... DEPARTMENT OF THE INTERIOR Bureau of Reclamation Central Valley Project Improvement Act, Water Management Plans AGENCY: Bureau of Reclamation, Interior. ACTION: Notice of availability. SUMMARY: The...

75 FR 38538 - Central Valley Project Improvement Act, Water Management Plans

Science.gov (United States)

2010-07-02

... to establish and administer an office on Central Valley Project water conservation best management... DEPARTMENT OF THE INTERIOR Bureau of Reclamation Central Valley Project Improvement Act, Water Management Plans AGENCY: Bureau of Reclamation, Interior. ACTION: Notice of availability. SUMMARY: The...

Modeling potential scenarios of the Tangjiashan Lake outburst and risk assessment in the downstream valley

Science.gov (United States)

Kidyaeva, Vera; Chernomorets, Sergey; Krylenko, Inna; Wei, Fangqiang; Petrakov, Dmitry; Su, Pengcheng; Yang, Hongjuan; Xiong, Junnan

2017-09-01

This research is devoted to Tangjiashan Lake, a quake landslide-dammed lake, situated in Sichuan Province, China, which was formed by a landslide triggered by the Wenchuan Earthquake on 12 May 2008. A STREAM_2D two-dimensional hydrodynamic model of Russia was applied to simulate the process of two flood scenarios: 1, lake dam outbreak, and 2, dam overtopping. An artificial dam outbreak was made after the earthquake to lower the water level of the lake in 2008, which led to a great flood with a maximum water discharge of more than 6400 m3/s. The negative impact of the flood was reduced by a timely evacuation of the population. Flood hazards still remain in the event of new landslides into the lake and lake dam overtopping (Scenario 2), in which case a maximum water discharge at the dam crest would reach 5000 m3/s, placing the population of Shabacun and Shilingzi villages in the zone of flood impact.

Hydrology and water quality of Park Lake, south-central Wisconsin

Science.gov (United States)

Kammerer, P.A.

1996-01-01

Park Lake extends to the northeast from the village of Pardeeville in Columbia County (fig. 1). Local residents perceive water-quality problems in the lake that include excessive algae and aquatic plant growth. Algae and plant growth in a lake are controlled, in part, by the availability of phosphorus in the water. However, no measurements of phosphorus enter- ing the lake or of other factors that affect lake-water quality had been made, and available data on water quality were limited to 2 years of measurements at one site in the lake in 1986- 87. To obtain the data and in- formation needed to address the water-quality problems at Park Lake and to develop a management plan that would limit the input of phosphorus to the lake, the U.S. Geologi- cal Survey, in cooperation with the Park Lake Management District, studied the hydrology of the lake and collected data needed to determine sources and amount of phosphorus en- tering the lake. This Fact Sheet summarizes the results of that study. Data collected during the study were published in a separate report (Holmstrom and others, 1994, p. 70-85).

Hydrogeologic characteristics and geospatial analysis of water-table changes in the alluvium of the lower Arkansas River Valley, southeastern Colorado, 2002, 2008, and 2015

Science.gov (United States)

Holmberg, Michael J.

2017-05-15

The U.S. Geological Survey in cooperation with the Lower Arkansas Valley Water Conservancy District measures groundwater levels periodically in about 100 wells completed in the alluvial material of the Arkansas River Valley in Pueblo, Crowley, Otero, Bent, and Prowers Counties in southeastern Colorado, of which 95 are used for the analysis in this report. The purpose of this report is to provide information to water-resource administrators, managers, planners, and users about groundwater characteristics in the alluvium of the lower Arkansas Valley extending roughly 150 miles between Pueblo Reservoir and the Colorado-Kansas State line. This report includes three map sheets showing (1) bedrock altitude at the base of the alluvium of the lower Arkansas Valley; (2) estimated spring-to-spring and fall-to-fall changes in water-table altitude between 2002, 2008, and 2015; and (3) estimated saturated thickness in the alluvium during spring and fall of 2002, 2008, and 2015, and thickness of the alluvium in the lower Arkansas Valley. Water-level changes were analyzed by geospatial interpolation methods.Available data included all water-level measurements made between January 1, 2001, and December 31, 2015; however, only data from fall and spring of 2002, 2008, and 2015 are mapped in this report. To account for the effect of John Martin Reservoir in Bent County, Colorado, lake levels at the reservoir were assigned to points along the approximate shoreline and were included in the water-level dataset. After combining the water-level measurements and lake levels, inverse distance weighting was used to interpolate between points and calculate the altitude of the water table for fall and spring of each year for comparisons. Saturated thickness was calculated by subtracting the bedrock surface from the water-table surface. Thickness of the alluvium was calculated by subtracting the bedrock surface from land surface using a digital elevation model.In order to analyze the response

Cold Lake-Beaver River water management study update: Report of the Cold Lake Regional Water Management Task Force

International Nuclear Information System (INIS)

1994-01-01

The Cold Lake Regional Water Management Task Force was formed in 1992, comprising representatives from local governments, aboriginal groups, the oil industry, and the public. The Task Force's mandate was to advise Alberta Environmental Protection on updating the Cold Lake-Beaver River Water Management Plan, taking into acocunt the views and concerns of the public, industry, and local governments. Industrial water use was found to be the key issue to be addressed in the plan update, so the Task Force focused on reviewing industrial water supply options and developing recommendations on the appropriate water supply to meet long-term requirements. A subcommittee was established to monitor groundwater use by the heavy oil industry. This committee took readings at Imperial Oil's water production and observation wells on a biweekly basis. Nine options for supplying industrial water requirements were examined and evaluated using criteria including supply reliability, economic factors, and impacts on other users and the environment. The Task Force found that the preferred source of water for industrial use is the North Saskatchewan River, to be accessed by a water pipeline. The second and less desirable source of water for industrial use would be a system of weirs on Cold or Primrose Lakes and Wolf Lake, supplemented by the use of brackish water to the maximum extent possible. In the interim, industry was recommended to maximize its use of brackish water and continue to use surface and ground water within existing license limits. Other recommendations were to form provincial or regional boards to oversee water use and issue water licenses, to treat water as a resource, and to establish a fee for industrial use of water. 3 figs., 5 tabs

Multi-Elements in Waters and Sediments of Shallow Lakes: Relationships with Water, Sediment, and Watershed Characteristics.

Science.gov (United States)

Kissoon, La Toya T; Jacob, Donna L; Hanson, Mark A; Herwig, Brian R; Bowe, Shane E; Otte, Marinus L

2015-06-01

We measured concentrations of multiple elements, including rare earth elements, in waters and sediments of 38 shallow lakes of varying turbidity and macrophyte cover in the Prairie Parkland (PP) and Laurentian Mixed Forest (LMF) provinces of Minnesota. PP shallow lakes had higher element concentrations in waters and sediments compared to LMF sites. Redundancy analysis indicated that a combination of site- and watershed-scale features explained a large proportion of among-lake variability in element concentrations in lake water and sediments. Percent woodland cover in watersheds, turbidity, open water area, and macrophyte cover collectively explained 65.2 % of variation in element concentrations in lake waters. Sediment fraction smaller than 63 µm, percent woodland in watersheds, open water area, and sediment organic matter collectively explained 64.2 % of variation in element concentrations in lake sediments. In contrast to earlier work on shallow lakes, our results showed the extent to which multiple elements in shallow lake waters and sediments were influenced by a combination of variables including sediment characteristics, lake morphology, and percent land cover in watersheds. These results are informative because they help illustrate the extent of functional connectivity between shallow lakes and adjacent lands within these lake watersheds.

Water Quality and Hydrology of Silver Lake, Barron County, Wisconsin, With Special Emphasis on Responses of a Terminal Lake to Changes in Phosphorus Loading and Water Level

Science.gov (United States)

Robertson, Dale M.; Rose, William J.; Fitzpatrick, Faith A.

2009-01-01

Silver Lake is typically an oligotrophic-to-mesotrophic, soft-water, terminal lake in northwestern Wisconsin. A terminal lake is a closed-basin lake with surface-water inflows but no surface-water outflows to other water bodies. After several years with above-normal precipitation, very high water levels caused flooding of several buildings near the lake and erosion of soil around much of the shoreline, which has been associated with a degradation in water quality (increased phosphorus and chlorophyll a concentrations and decreased water clarity). To gain a better understanding of what caused the very high water levels and degradation in water quality and collect information to better understand the lake and protect it from future degradation, the U.S. Geological Survey did a detailed study from 2004 to 2008. This report describes results of the study; specifically, lake-water quality, historical changes in water level, water and phosphorus budgets for the two years monitored in the study, results of model simulations that demonstrate how changes in phosphorus inputs affect lake-water quality, and the relative importance of changes in hydrology and changes in the watershed to the water quality of the lake. From 1987 to about 1996, water quality in Silver Lake was relatively stable. Since 1996, however, summer average total phosphorus concentrations increased from about 0.008 milligrams per liter (mg/L) to 0.018 mg/L in 2003, before decreasing to 0.011 mg/L in 2008. From 1996 to 2003, Secchi depths decreased from about 14 to 7.4 feet, before increasing to about 19 feet in 2008. Therefore, Silver Lake is typically classified as oligotrophic to mesotrophic; however, during 2002-4, the lake was classified as mesotrophic to eutrophic. Because productivity in Silver Lake is limited by phosphorus, phosphorus budgets for the lake were constructed for monitoring years 2005 and 2006. The average annual input of phosphorus was 216 pounds: 78 percent from tributary and

Water quality and bathymetry of Sand Lake, Anchorage, Alaska

Science.gov (United States)

Donaldson, Donald E.

1976-01-01

Sand Lake, a dimictic lowland lake in Anchorage, Alaska, has recently become as urban lake. Analyses indicate that the lake is oligotrophic, having low dissolved solids and nutrient concentrations. Snowmelt runoff from an adjacent residential area, however, has a dissolved-solids concentration 10 times that of the main body of Sand Lake. Lead concentrations in the runoff exceed known values from other water in the ANchorage area, including water samples taken beneath landfills. The volume of the snowmelt runoff has not been measured. The data presented can be used as a baseline for water-resource management. (Woodard-USGS)

ETV REPORT: REMOVAL OF ARSENIC IN DRINKING WATER — BASIN WATER HIGH EFFICIENCY ION EXCHANGE WATER TREATMENT SYSTEM

Science.gov (United States)

Verification testing of the Basin Water System was conducted over a 54-day period between April 4, 2005 and May 28, 2005. The test was conducted at the Elsinore Valley Municipal Water District (EVMWD) Corydon Street Well in Lake Elsinore, California. The source water was a raw gr...

A System Dynamics Modeling of Water Supply and Demand in Las Vegas Valley

Science.gov (United States)

Parajuli, R.; Kalra, A.; Mastino, L.; Velotta, M.; Ahmad, S.

2017-12-01

The rise in population and change in climate have posed the uncertainties in the balance between supply and demand of water. The current study deals with the water management issues in Las Vegas Valley (LVV) using Stella, a system dynamics modeling software, to model the feedback based relationship between supply and demand parameters. Population parameters were obtained from Center for Business and Economic Research while historical water demand and conservation practices were modeled as per the information provided by local authorities. The water surface elevation of Lake Mead, which is the prime source of water supply to the region, was modeled as the supply side whereas the water demand in LVV was modeled as the demand side. The study was done from the period of 1989 to 2049 with 1989 to 2012 as the historical one and the period from 2013 to 2049 as the future period. This study utilizes Coupled Model Intercomparison Project data sets (2013-2049) (CMIP3&5) to model different future climatic scenarios. The model simulates the past dynamics of supply and demand, and then forecasts the future water budget for the forecasted future population and future climatic conditions. The results can be utilized by the water authorities in understanding the future water status and hence plan suitable conservation policies to allocate future water budget and achieve sustainable water management.

Research objectives to support the South Florida Ecosystem Restoration initiative-Water Conservation Areas, Lake Okeechobee, and the East/West waterways

OpenAIRE

Kitchens, Wiley M.

1994-01-01

The South Florida Ecosystem encompasses an area of approximately 28,000 km2 comprising at least 11 major physiographic provinces, including the Kissimmee River Valley, Lake Okeechobee, the Immokalee Rise, the Big Cypress, the Everglades, Florida Bay, the Atlantic Coastal Ridge, Biscayne Bay, the Florida Keys, the Florida Reef Tract, and nearshore coastal waters. South Florida is a heterogeneous system of wetlands, uplands, coastal areas, and marine areas, dominated by the watershe...

Groundwater and surface-water interactions near White Bear Lake, Minnesota, through 2011

Science.gov (United States)

Jones, Perry M.; Trost, Jared J.; Rosenberry, Donald O.; Jackson, P. Ryan; Bode, Jenifer A.; O'Grady, Ryan M.

2013-01-01

The U.S. Geological Survey, in cooperation with the White Bear Lake Conservation District, the Minnesota Pollution Control Agency, the Minnesota Department of Natural Resources, and other State, county, municipal, and regional planning agencies, watershed organizations, and private organizations, conducted a study to characterize groundwater and surface-water interactions near White Bear Lake through 2011. During 2010 and 2011, White Bear Lake and other lakes in the northeastern part of the Twin Cities Metropolitan Area were at historically low levels. Previous periods of lower water levels in White Bear Lake correlate with periods of lower precipitation; however, recent urban expansion and increased pumping from the Prairie du Chien-Jordan aquifer have raised the question of whether a decline in precipitation is the primary cause for the recent water-level decline in White Bear Lake. Understanding and quantifying the amount of groundwater inflow to a lake and water discharge from a lake to aquifers is commonly difficult but is important in the management of lake levels. Three methods were used in the study to assess groundwater and surface-water interactions on White Bear Lake: (1) a historical assessment (1978-2011) of levels in White Bear Lake, local groundwater levels, and their relation to historical precipitation and groundwater withdrawals in the White Bear Lake area; (2) recent (2010-11) hydrologic and water-quality data collected from White Bear Lake, other lakes, and wells; and (3) water-balance assessments for White Bear Lake in March and August 2011. An analysis of covariance between average annual lake-level change and annual precipitation indicated the relation between the two variables was significantly different from 2003 through 2011 compared with 1978 through 2002, requiring an average of 4 more inches of precipitation per year to maintain the lake level. This shift in the linear relation between annual lake-level change and annual precipitation

Seeing Water in Early Twentieth-Century Mexico City: Henry Wellge's Perspective Plan of the City and Valley of Mexico, D.F. 1906

OpenAIRE

Widdifield, Stacie G.; Banister, Jeffrey M.

2015-01-01

We examine Henry Wellge's 1906 chromolithograph, Perspective Plan of the City and Valley of Mexico, D.F., a panoramic view that organizes the capital and its lacustrine environs through close up and distant perspectives. The Plan depicts a landscape integrated by canals, rivers, and lakes, recording a pivotal moment before modern hydraulic infrastructure would remove surface water from view. We thus interrogate this image as a visual register of hydraulic-control ideals in vogue around 1900, ...

Watershed land use effects on lake water quality in Denmark

DEFF Research Database (Denmark)

Nielsen, Anders; Trolle, Dennis; Søndergaard, Martin

2012-01-01

Mitigating nutrient losses from anthropogenic nonpoint sources is today of particular importance for improving the water quality of numerous freshwater lakes worldwide. Several empirical relationships between land use and in-lake water quality variables have been developed, but they are often weak......, which can in part be attributed to lack of detailed information about land use activities or point sources. We examined a comprehensive data set comprising land use data, point-source information, and in-lake water quality for 414 Danish lakes. By excluding point-source-influenced lakes (n = 210....... Relationships between TP and agricultural land use were even stronger for lakes with rivers in their watershed (55%) compared to lakes without (28%), indicating that rivers mediate a stronger linkage between landscape activity and lake water quality by providing a “delivery” mechanism for excess nutrients...

Is water age a reliable indicator for evaluating water quality effectiveness of water diversion projects in eutrophic lakes?

Science.gov (United States)

Zhang, Xiaoling; Zou, Rui; Wang, Yilin; Liu, Yong; Zhao, Lei; Zhu, Xiang; Guo, Huaicheng

2016-11-01

Water diversion has been applied increasingly to promote the exchange of lake water and to control eutrophication of lakes. The accelerated water exchange and mass transport by water diversion can usually be represented by water age. But the responses of water quality after water diversion is still disputed. The reliability of using water age for evaluating the effectiveness of water diversion projects in eutrophic lakes should be thereby explored further. Lake Dianchi, a semi-closed plateau lake in China, has suffered severe eutrophication since the 1980s, and it is one of the three most eutrophic lakes in China. There was no significant improvement in water quality after an investment of approximately 7.7 billion USD and numerous project efforts from 1996 to 2015. After the approval of the Chinese State Council, water has been transferred to Lake Dianchi to alleviate eutrophication since December 2013. A three-dimensional hydrodynamic and water quality model and eight scenarios were developed in this study to quantity the influence of this water diversion project on water quality in Lake Dianchi. The model results showed that (a) Water quality (TP, TN, and Chla) could be improved by 13.5-32.2%, much lower than the approximate 50% reduction in water age; (b) Water exchange had a strong positive relationship with mean TP, and mean Chla had exactly the same response to water diversion as mean TN; (c) Water level was more beneficial for improving hydrodynamic and nutrient concentrations than variation in the diverted inflowing water volume; (d) The water diversion scenario of doubling the diverted inflow rate in the wet season with the water level of 1886.5 m and 1887 m in the remaining months was the best water diversion mode for mean hydrodynamics and TP, but the scenario of doubling the diverted inflow rate in the wet season with 1887 m throughout the year was optimum for mean TN and Chla; (e) Water age influenced the effectiveness of water diversion on the

Analysis of black water aggregation in Taihu Lake

Directory of Open Access Journals (Sweden)

Gui-hua Lu

2011-12-01

Full Text Available Black water aggregation (BWA in Taihu Lake is a disaster for the lake environment. It is a phenomenon resulting from water environmental deterioration and eutrophication caused by accumulation of pollutants in the lake, according to research on the water quality, pollutants of BWA, and occurrence mechanisms of BWA. Dead algae are the material base of BWA, the polluted sediment is an important factor for the formation of BWA, and hydrological and meteorological conditions such as sun light, air temperature, wind speed, and water flow are the other factors that may lead to the formation of BWA. Thioether substances such as dimethyl trisulfide are the representative pollutants of BWA. Parameters such as chlorophyll-a, DO, pH, and water temperature are sensitive indicators of BWA. Measures such as algae collection, ecological dredging, pollution control, and water diversion from the Yangtze River to the lake, are effective, and strengthening aeration is an emergency measure to control BWA.

Influence of the Sostanj coal-fired thermal power plant on mercury and methyl mercury concentrations in Lake Velenje, Slovenia

Energy Technology Data Exchange (ETDEWEB)

Kotnik, J.; Horvat, M.; Mandic, V.; Logar, M. [Department of Environmental Sciences, Jozef Stefan Institute, Jamova 39, 1000 Ljubljana (Slovenia)

2000-10-02

Lake Velenje is located in one of the most polluted regions in Slovenia, the Salek Valley. The major source of pollution in the valley is the coal-fired thermal power plant in Sostanj (STPP, capacity 775 MW). It has five separate units. All units have electrostatic precipitators for fly ash removal. Unit 4 also has installed a wet flue gas desulfurisation system (FGD system). Total mercury (THg) concentrations were measured in lignite, slag and ash samples from the STPP. In flue gas, different mercury species (THg, MeHg, Hg{sup 2+}, Hg{sup 0}) were determined separately for unit 4 and unit 5 which use different flue gas cleaning technology. Mercury and methyl mercury (MeHg) concentrations were also measured in lake water at different depths, in inflow water, outflow water, rain, snow and lake sediments in order to establish the influence of the power plant on the lake. Most mercury emitted from the power plant is in the elemental form. The ratio between oxidised and elemental Hg depends on the flue gas cleaning technology. Mass balance calculations have been performed for the STPP. The results show that the major sources of mercury in Lake Velenje are wet deposition and lake inflows. Total and MeHg concentrations in the water column are very low and can be compared to other non-contaminated freshwater lakes in the world.

Influence of the Sostanj coal-fired thermal power plant on mercury and methyl mercury concentrations in Lake Velenje, Slovenia

Science.gov (United States)

Kotnik; Horvat; Mandic; Logar

2000-10-02

Lake Velenje is located in one of the most polluted regions in Slovenia, the Salek Valley. The major source of pollution in the valley is the coal-fired thermal power plant in Sostanj (STPP, capacity 775 MW). It has five separate units. All units have electrostatic precipitators for fly ash removal. Unit 4 also has installed a wet flue gas desulfurisation system (FGD system). Total mercury (THg) concentrations were measured in lignite, slag and ash samples from the STPP. In flue gas, different mercury species (THg, MeHg, Hg2+, Hg0) were determined separately for unit 4 and unit 5 which use different flue gas cleaning technology. Mercury and methyl mercury (MeHg) concentrations were also measured in lake water at different depths, in inflow water, outflow water, rain, snow and lake sediments in order to establish the influence of the power plant on the lake. Most mercury emitted from the power plant is in the elemental form. The ratio between oxidised and elemental Hg depends on the flue gas cleaning technology. Mass balance calculations have been performed for the STPP. The results show that the major sources of mercury in Lake Velenje are wet deposition and lake inflows. Total and MeHg concentrations in the water column are very low and can be compared to other non-contaminated freshwater lakes in the world.

Noble Gases in Lakes and Ground Waters

OpenAIRE

Kipfer, Rolf; Aeschbach-Hertig, Werner; Peeters, Frank; Stute, Marvin

2002-01-01

In contrast to most other fields of noble gas geochemistry that mostly regard atmospheric noble gases as 'contamination,' air-derived noble gases make up the far largest and hence most important contribution to the noble gas abundance in meteoric waters, such as lakes and ground waters. Atmospheric noble gases enter the meteoric water cycle by gas partitioning during air / water exchange with the atmosphere. In lakes and oceans noble gases are exchanged with the free atmosphere at the surface...

Water Surface Overgrowing of the Tatra’s Lakes

Directory of Open Access Journals (Sweden)

Kapusta Juraj

2018-03-01

Full Text Available Tatra’s lakes are vulnerable ecosystems and an important element of the alpine landscape. Mainly some shallow lake basins succumb to intense detritus sedimentation, fine fractions of material from the catchment area or to the overgrowing of water level by vegetation. In this paper, changes and dynamics of the 12 Tatra’s lake shorelines that were selected based on the detailed mapping of their extent are pointed out. Changes were assessed by accurate comparisons of historical and current orthophoto maps from the years 1949, 1955 and 2015 – and therefore, based on the oldest and the latest relevant materials. Due to the overgrowing of lakes caused by vegetation, their water surface decreased from −0.9% up to −47.9%, during the examined period. Losses were caused by the overgrowing of open water surface by the communities of sedges and peat bogs. The most significant dynamics of the shorelines during the last decades were reached by those lakes, into which fine sediments were simultaneously deposited by means of mountain water coarse. These sediments made the marginal parts of the lake basins shallower and accelerated rapid expansion of vegetation to the detriment of the open water surface. The overgrowing of shallow moraine lakes lying in the vegetation zone is a significant phenomenon of the High Tatras alpine landscape. It leads to their gradual extinction, turn into peat bogs and wet alpine meadows.

Lake water quality: Chapter 4 in A synthesis of aquatic science for management of Lakes Mead and Mohave

Science.gov (United States)

Tietjen, Todd; Holdren, G. Chris; Rosen, Michael R.; Veley, Ronald J.; Moran, Michael J.; Vanderford, Brett; Wong, Wai Hing; Drury, Douglas D.

2012-01-01

Given the importance of the availability and quality of water in Lake Mead, it has become one of the most intensely sampled and studied bodies of water in the United States. As a result, data are available from sampling stations across the lake (fig. 4-1 and see U.S. Geological Survey Automated Water-Quality Platforms) to provide information on past and current (2012) water-quality conditions and on invasive species that influence—and are affected by—water quality. Water quality in Lakes Mead and Mohave generally exceeds standards set by the State of Nevada to protect water supplies for public uses: drinking water, aquatic ecosystem health, recreation, or agricultural irrigation. In comparison to other reservoirs studied by the U.S. Environmental Protection Agency (USEPA) for a national lake assessment (U.S. Environmental Protection Agency, 2010), Lake Mead is well within the highest or ‘good’ category for recreation and aquatic health (see U.S. Environmental Protection Agency National Lakes Assessment and Lake Mead for more details). While a small part of the lake, particularly Las Vegas Bay, is locally influenced by runoff from urbanized tributaries such as Las Vegas Wash, contaminant loading in the lake as a whole is low compared to other reservoirs in the nation, which are influenced by runoff from more heavily urbanized watersheds (Rosen and Van Metre, 2010).

Environmental Monitoring, Water Quality - Lakes Assessments - Non Attaining

Data.gov (United States)

NSGIC Education | GIS Inventory — This layer shows only non attaining lakes of the Integrated List. The Lakes Integrated List represents lake assessments in an integrated format for the Clean Water...

Hydrology and water quality of East Lake Tohopekaliga, Osceola County, Florida

Science.gov (United States)

Schiffer, Donna M.

1987-01-01

East Lake Tohopekaliga, one of the major lakes in central Florida, is located in the upper Kissimmee River basin in north-east Osceola County. It is one of numerous lakes in the upper basin used for flood control, in addition to recreation and some irrigation of surrounding pasture. This report is the fourth in a series of lake reconnaissance studies in the Kissimmee River basin prepared in cooperation with the South Florida Water Management District. The purpose of the report is to provide government agencies and the public with a brief summary of the lake 's hydrology and water quality. Site information is given and includes map number, site name, location, and type of data available (specific conductivity, pH, alkalinity, turbidity, color, dissolved oxygen, hardness, dissolved chlorides, dissolved sodium, dissolved calcium, dissolved magnesium, dissolved potassium, nitrogen, ammonia, nitrates, carbon and phosphorus). The U.S. Geological Survey (USGS) maintained a lake stage gaging station on East Lake Tohopekaliga from 1942 to 1968. The South Florida Water Management District has recorded lake stage since 1963. Periodic water quality samples have been collected from the lake by the South Florida Water Management District and USGS. Water quality and discharge data have been collected for one major tributary to the lake, Boggy Creek. Although few groundwater data are available for the study area, results of previous studies of the groundwater resources of Osceola County are included in this report. To supplement the water quality data for East Lake Tohopekaliga, water samples were collected at selected sites in November 1982 (dry season) and in August 1983 (rainy season). Samples were taken at inflow points, and in the lake, and vertical profiles of dissolved oxygen and temperature were measured in the lake. A water budget from an EPA report on the lake is also included. (Lantz-PTT)

Hydrochemistry of the Lake Magadi basin, Kenya

Science.gov (United States)

Jones, B.F.; Eugster, H.P.; Rettig, S.L.

1977-01-01

New and more complete compositional data are presented for a large number of water samples from the Lake Magadi area, Kenya. These water samples range from dilute inflow (300 g/kg dissolved solids). Five distinct hydrologic stages can be recognized in the evolution of the water compositions: dilute streamflow, dilute ground water, saline ground water (or hot spring reservoir), saturated brines, and residual brines. Based on the assumption that chloride is conserved in the waters during evaporative concentration, these stages are related to each other by the concentration factors of about 1:28:870:7600:16,800. Dilute streamflow is represented by perennial streams entering the Rift Valley from the west. All but one (Ewaso Ngiro) of these streams disappear in the alluvium and do not reach the valley floor. Dilute ground water was collected from shallow pits and wells dug into lake sediments and alluvial channels. Saline ground water is roughly equivalent to the hot springs reservoir postulated by Eugster (1970) and is represented by the hottest of the major springs. Saturated brines represent surficial lake brines just at the point of saturation with respect to trona (Na2CO3.NaHCO3.2H2O), while residual brines are essentially interstitial to the evaporite deposit and have been subjected to a complex history of precipitation and re-solution. The new data confirm the basic hydrologic model presented by Eugster (1970) which has now been refined, particularly with respect to the early stages of evaporative concentration. Budget calculations show that only bromide is conserved as completely as chloride. Sodium follows chloride closely until trona precipitation, whereas silica and sulfate are largely lost during the very first concentration' step (dilute streamflow-dilute ground water). A large fraction of potassium and all calcium plus magnesium are removed during the first two concentration steps (dilute streamflow-dilute ground water-saline ground water). Carbonate and

Speculations on the spatial setting and temporal evolution of a fjord-style lake

Science.gov (United States)

Sarnthein, M.; Spötl, C.

2012-04-01

The Inn Valley, a classical region of Quaternary research in the Alps, is bordered by terraces that extend over almost 70 km and record an ancient lake with a lake level near 750-830 m above sea level (a.s.l.), about 250-300 m above the modern valley floor. Over large distances, the terrace sediments consist mainly of laminated "Banded Clays", above ~750 m a.s.l. overlain by glaciofluvial gravel and finally, by tills that record the Upper Würmian ice advance of Marine Isotope Stage (MIS) 2. In the (former) clay pit of Baumkirchen this boundary forms the Alpine type locality for the onset of the Upper Würmian, well supported by 14C-based age control first established by Fliri (1971). On the basis of a recently cored sediment section at Baumkirchen, the >200 m thick "Banded Clays" store a continuous, largely undisturbed, highly resolved, and widely varved climatic archive of MIS 3. Major unknowns concern the location and origin of dams that may have barred the vast and deep Inn Valley lake. We discuss potential linkages to the pattern of moraines and ice advance of MIS 4 glaciers, which was less prominent than during MIS 2, thus leading to a distinct east-west segment¬ation of the run-off systems in Tyrol. East of Imst, for example, the lake was possibly barred by both a rock sill reaching up to 830 m a.s.l. and a lateral moraine deposited by an Ötz Valley glacier. 80 km further east, a lateral moraine of a glacier advancing from the Ziller Valley may have barred the ancient Inn Valley lake to the east. The final rapid coarsening of clastic lake sediments at the end of MIS 3 is widely ascribed to major climatic deter¬ioration. However, the MIS 3-2 boundary was linked to an only modest change of global climates and accordingly, different forcings may be considered. In turn, the rapid coarsening may document a date, when the Central Alpine glaciers had already filled the basin of Imst to the west of the Inn Valley lake. This ice mass may have forced the melt

SURFACE WATER AND GROUND WATER QUALITY MONITORING FOR RESTORATION OF URBAN LAKES IN GREATER HYDERABAD, INDIA

Science.gov (United States)

Mohanty, A. K.

2009-12-01

SURFACE WATER AND GROUND WATER QUALITY MONITORING FOR RESTORATION OF URBAN LAKES IN GREATER HYDERABAD, INDIA A.K. Mohanty, K. Mahesh Kumar, B. A. Prakash and V.V.S. Gurunadha Rao Ecology and Environment Group National Geophysical Research Institute, (CSIR) Hyderabad - 500 606, India E-mail:atulyakumarmohanty@yahoo.com Abstract: Hyderabad Metropolitan Development Authority has taken up restoration of urban lakes around Hyderabad city under Green Hyderabad Environment Program. Restoration of Mir Alam Tank, Durgamcheruvu, Patel cheruvu, Pedda Cheruvu and Nallacheruvu lakes have been taken up under the second phase. There are of six lakes viz., RKPuramcheruvu, Nadimicheruvu (Safilguda), Bandacheruvu Patelcheruvu, Peddacheruvu, Nallacheruvu, in North East Musi Basin covering 38 sq km. Bimonthly monitoring of lake water quality for BOD, COD, Total Nitrogen, Total phosphorous has been carried out for two hydrological cycles during October 2002- October 2004 in all the five lakes at inlet channels and outlets. The sediments in the lake have been also assessed for nutrient status. The nutrient parameters have been used to assess eutrophic condition through computation of Trophic Status Index, which has indicated that all the above lakes under study are under hyper-eutrophic condition. The hydrogeological, geophysical, water quality and groundwater data base collected in two watersheds covering 4 lakes has been used to construct groundwater flow and mass transport models. The interaction of lake-water with groundwater has been computed for assessing the lake water budget combining with inflow and outflow measurements on streams entering and leaving the lakes. Individual lake water budget has been used for design of appropriate capacity of Sewage Treatment Plants (STPs) on the inlet channels of the lakes for maintaining Full Tank Level (FTL) in each lake. STPs are designed for tertiary treatment i.e. removal of nutrient load viz., Phosphates and Nitrates. Phosphates are

Water hyacinth hotspots in the Ugandan waters of Lake Victoria in ...

African Journals Online (AJOL)

Water hyacinth invaded Lake Victoria in the 1980s and, by 1998, had attained peak coverage of approximately 2 000 ha in the Ugandan waters of the lake. Control interventions, especially via biological means, significantly reduced the weed's coverage to non-nuisance levels (<10 ha) by 1999. Although resurgence was ...

Stable water isotopic composition of the Antarctic subglacial Lake Vostok: implications for understanding the lake's hydrology.

Science.gov (United States)

Ekaykin, Alexey A; Lipenkov, Vladimir Y; Kozachek, Anna V; Vladimirova, Diana O

2016-01-01

We estimated the stable isotopic composition of water from the subglacial Lake Vostok using two different sets of samples: (1) water frozen on the drill bit immediately after the first lake unsealing and (2) water frozen in the borehole after the unsealing and re-drilled one year later. The most reliable values of the water isotopic composition are: -59.0 ± 0.3 ‰ for oxygen-18, -455 ± 1 ‰ for deuterium and 17 ± 1 ‰ for d-excess. This result is also confirmed by the modelling of isotopic transformations in the water which froze in the borehole, and by a laboratory experiment simulating this process. A comparison of the newly obtained water isotopic composition with that of the lake ice (-56.2 ‰ for oxygen-18, -442.4 ‰ for deuterium and 7.2 ‰ for d-excess) leads to the conclusion that the lake ice is very likely formed in isotopic equilibrium with water. In turn, this means that ice is formed by a slow freezing without formation of frazil ice crystals and/or water pockets. This conclusion agrees well with the observed physical and chemical properties of the lake's accreted ice. However, our estimate of the water's isotopic composition is only valid for the upper water layer and may not be representative for the deeper layers of the lake, so further investigations are required.

Hydrochemical determination of source water contributions to Lake Lungo and Lake Ripasottile (central Italy

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Claire Archer

2016-12-01

Full Text Available Lake Lungo and Lake Ripasottile are two shallow (4-5 m lakes located in the Rieti Basin, central Italy, that have been described previously as surface outcroppings of the groundwater table. In this work, the two lakes as well as springs and rivers that represent their potential source waters are characterized physio-chemically and isotopically, using a combination of environmental tracers. Temperature and pH were measured and water samples were analyzed for alkalinity, major ion concentration, and stable isotope (δ2H, δ18O, δ13C of dissolved inorganic carbon, and δ34S and δ18O of sulfate composition.  Chemical data were also investigated in terms of local meteorological data (air temperature, precipitation to determine the sensitivity of lake parameters to changes in the surrounding environment. Groundwater represented by samples taken from Santa Susanna Spring was shown to be distinct with SO42- and Mg2+ content of 270 and 29 mg/L, respectively, and heavy sulfate isotopic composition (δ34S=15.2 ‰ and δ18O=10‰. Outflow from the Santa Susanna Spring enters Lake Ripasottile via a canal and both spring and lake water exhibits the same chemical distinctions and comparatively low seasonal variability. Major ion concentrations in Lake Lungo are similar to the Vicenna Riara Spring and are interpreted to represent the groundwater locally recharged within the plain. The δ13CDIC exhibit the same groupings as the other chemical parameters, providing supporting evidence of the source relationships. Lake Lungo exhibited exceptional ranges of δ13CDIC (±5 ‰ and δ2H, δ18O (±5 ‰ and ±7 ‰, respectively, attributed to sensitivity to seasonal changes. The hydrochemistry results, particularly major ion data, highlight how the two lakes, though geographically and morphologically similar, represent distinct hydrochemical facies. These data also show a different response in each lake to temperature and precipitation patterns in the basin that

Simulation of ground-water flow and land subsidence in the Antelope Valley ground-water basin, California

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Leighton, David A.; Phillips, Steven P.

2003-01-01

Antelope Valley, California, is a topographically closed basin in the western part of the Mojave Desert, about 50 miles northeast of Los Angeles. The Antelope Valley ground-water basin is about 940 square miles and is separated from the northern part of Antelope Valley by faults and low-lying hills. Prior to 1972, ground water provided more than 90 percent of the total water supply in the valley; since 1972, it has provided between 50 and 90 percent. Most ground-water pumping in the valley occurs in the Antelope Valley ground-water basin, which includes the rapidly growing cities of Lancaster and Palmdale. Ground-water-level declines of more than 200 feet in some parts of the ground-water basin have resulted in an increase in pumping lifts, reduced well efficiency, and land subsidence of more than 6 feet in some areas. Future urban growth and limits on the supply of imported water may continue to increase reliance on ground water. To better understand the ground-water flow system and to develop a tool to aid in effectively managing the water resources, a numerical model of ground-water flow and land subsidence in the Antelope Valley ground-water basin was developed using old and new geohydrologic information. The ground-water flow system consists of three aquifers: the upper, middle, and lower aquifers. The aquifers, which were identified on the basis of the hydrologic properties, age, and depth of the unconsolidated deposits, consist of gravel, sand, silt, and clay alluvial deposits and clay and silty clay lacustrine deposits. Prior to ground-water development in the valley, recharge was primarily the infiltration of runoff from the surrounding mountains. Ground water flowed from the recharge areas to discharge areas around the playas where it discharged either from the aquifer system as evapotranspiration or from springs. Partial barriers to horizontal ground-water flow, such as faults, have been identified in the ground-water basin. Water-level declines owing to

Monitoring of Bashkara glacial lakes (the Central Caucasus) and modelling of their potential outburst.

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Krylenko, I.; Norin, S.; Petrakov, D.; Tutubalina, O.; Chernomorets, S.

2009-04-01

In recent decades due to glacier retreat the glacial lakes in the Central Caucasus, as well as in other high-mountainous areas of the world, have expanded intensively. As result the risk of lake outbursts and destructive floods is raising. In this paper we present one of the most potentially hazardous lakes of this region - a group of glacial lakes near the Bashkara glacier in the upper Adylsu river valley, to the southeast of Mt. Elbrus. Total area of these lakes is about 100,000m2, and a total volume exceeds 1,000,000 m3. The biggest of them - the Bashkara lake has formed in late 1930s - early 1940s and the small Lapa lake has appeared in the end of 1980s. The Bashkara lake outburst occurred twice in the end of 1950s and produced devastating debris flows of ca. 2 million m3. We have monitored these lakes since 1999. Our work includes detailed field research: constant measurements of water level during warm period, annually repeated bathymetric surveys, geodetic surveys, observations on dam condition and some special measurements (i.e. water temperature distribution, current velocity). Also we use aerial and satellite images to obtain data about dynamic of areas for the lakes. From 2001 to 2006 years volume of the Lapa lake has increased 5 times (from 30,000 m3 to 140,000 m3), the Bashkara lake in this period was quasi-stable. In 2006-2008 volume of the Lapa lake has decreased due to sedimentation, however, rapid growth of water level in Bashkara lake (more than 20 sm. per day) has suddenly begun. As a result, volume of the Bashkara lake exceeded 1,000000 m3 in July 2008 whereas in 2001 -2007 year it was about 800,000 m3. Previous maximum of water level was exceeded on 3,5 m, moraine dam with ice core was overtopped and overflow has started. Thus, Bashkara glacier lakes are unstable and risk of outburst is increasing. To assess parameters and zones of potential outburst flood in the Adylsu River valley we have carried out hydrodynamic simulation. Two computer

Restoration of Eutrophic Lakes with Fluctuating Water Levels: A 20-Year Monitoring Study of Two Inter-Connected Lakes

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Meryem Beklioğlu

2017-02-01

Full Text Available Eutrophication continues to be the most important problem preventing a favorable environmental state and detrimentally impacting the ecosystem services of lakes. The current study describes the results of analyses of 20 year monitoring data from two interconnected Anatolian lakes, Lakes Mogan and Eymir, receiving sewage effluents and undergoing restoration. The first step of restoration in both lakes was sewage effluent diversion. Additionally, in hypertrophic Lake Eymir, biomanipulation was conducted, involving removal of benthi-planktivorous fish and prohibition of pike fishing. The monitoring period included high (H and low (L water levels (WL enabling elucidation of the effects of hydrological changes on lake restoration. In shallower Lake Mogan, macrophyte abundance increased after the sewage effluent diversion in periods with low water levels even at turbid water. In comparatively deeper Lake Eymir, the first biomanipulation led to a clear water state with abundant macrophyte coverage. However, shortly after biomanipulation, the water clarity declined, coinciding with low water level (LWL periods during which nutrient concentrations increased. A second biomanipulation was conducted, mostly during high water level (HWL period, resulting in a major decrease in nutrient concentrations and clearer water, but without an expansion of macrophytes. We conclude that repetitive fish removal may induce recovery but its success may be confounded by high availability of nutrients and adverse hydrological conditions.

Water Quality Investigations at Lake Merritt in Oakland, California

Science.gov (United States)

Carter, G.; Casino, C.; Johnson, K.; Huang, J.; Le, A.; Truisi, V. M.; Turner, D.; Yanez, F.; Yu, J. F.; Unigarro, M.; Vue, G.; Garduno, L.; Cuff, K.

2005-12-01

Lake Merritt is a saltwater tidal lagoon that forms a portion of a wildlife refuge in downtown Oakland, California. The general area was designated as the nation's first wildlife refuge in 1869, and is currently the home to over 90 species of migrating waterfowl, as well as a variety of aquatic wildlife. Situated within an area composed of compacted marine sediment located near the center of Oakland, Lake Merritt also serves as a major local catchment basin, receiving significant urban runoff from a 4,650 acre local watershed through 60 storm drains and four culverted creeks. Due to factors related to its geographical location, Lake Merritt has suffered from poor water quality at various times throughout its history. In fact, in May of 1999 the US Environmental Protection Agency designated Lake Merritt as a body of water whose beneficial uses are impaired, mainly due to high levels of trash and low levels of dissolved oxygen. As a contribution to continuing efforts to monitor and assess water quality of the Lake, we began a water quality investigation during the Summer of 2005, which included the measurement of dissolved oxygen concentrations of samples collected near its surface at over 85 different locations. These measurements were made using a sensor attached to a PASCO data- logger. The sensor measures the electric current produced by a chemical reaction in its probe, which is composed of a platinum cathode and a silver anode surrounded by an electrolyte solution. Results of these measurements were statistically analyzed, mapped, and then used in assessing the quality of Lake Merritt's water, particularly in relation to supporting aquatic biota. Preliminary analysis of results obtained so far indicates that the highest quality waters in Lake Merritt occur in areas that are closest to a source of San Francisco Bay water, as well as those areas nearby where water circulation is robust. Significantly high levels of dissolved oxygen were measured in an area that

Evaluating Capability of Devils Lake Emergency Outlets in Lowering Lake Water Levels While Controlling flooding Damage to Downstream

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Shabani, A.; Zhang, X.

2017-12-01

Devils Lake is an endorheic lake locate in the Red River of the North Basin with a natural outlet at a level of 444.7 meters above the sea level flowing into the Sheyenne River. Historical accumulation of salts has dramatically increased the concentration of salts in the lake, particularly of the sulfates, that are much greater than the surrounding water bodies. Since 1993, the lake water level has risen by nearly 10 meters and caused extensive flooding in the surrounding area, and greatly increased the chance of natural spillage to the Sheyenne River. To mitigate Devils Lake flooding and to prevent its natural spillage, two outlets were constructed at the west and east sides of the lake to drain the water to the Sheyenne River in a controlled fashion. However, pumping water from Devils Lake has degraded water quality of the Sheyenne River. In an earlier study, we coupled Soil and Water Assessment Tools (SWAT) and CE-QUAL-W2 models to investigate the changes of sulfate distribution as the lake water level rises. We found that, while operating the two outlets has lowered Devils Lake water level by 0.7 meter, it has also significantly impaired the Sheyenne River water quality, increasing the Sheyenne River average sulfate concentration from 105 to 585 mg l-1 from 2012 to 2014 In this study, we investigate the impact of the outlets on the Sheyenne River floodplain by coupling SWAT and HEC-RAS model. The SWAT model performed well in simulating daily streamflow in the Sheyenne River with R2>0.56 and ENS > 0.52. The simulated water depths and floodplain by HEC-RAS model for the Sheyenne River agreed well with observations. Operating the outlets from April to October can draw down the Devil Lake water level by 0.45 m, but the drained water would almost double the extension of the Sheyenne River floodplain and elevate the sulfate concentration in the Sheyenne River above the 450 mg l-1 North Dakota sulfate concentration standard for stream class I. Operating the outlets is

Modeling and management of pit lake water chemistry 1: Theory

International Nuclear Information System (INIS)

Castendyk, D.N.; Eary, L.E.; Balistrieri, L.S.

2015-01-01

Highlights: • Review of pit lake literature in the context of pit lake predictions. • Review of approaches used to predict pit wall-rock runoff and leachate. • Review of approaches used to generate a pit lake water balance. • Review of approaches used to generate a hydrodynamic prediction. • Review of approaches used to generate a geochemical prediction of a future pit lake. - Abstract: Pit lakes are permanent hydrologic/landscape features that can result from open pit mining for metals, coal, uranium, diamonds, oil sands, and aggregates. Risks associated with pit lakes include local and regional impacts to water quality and related impacts to aquatic and terrestrial ecosystems. Stakeholders rely on predictive models of water chemistry to prepare for and manage these risks. This paper is the first of a two part series on the modeling and management of pit lakes. Herein, we review approaches that have been used to quantify wall-rock runoff geochemistry, wall-rock leachate geochemistry, pit lake water balance, pit lake limnology (i.e. extent of vertical mixing), and pit lake water quality, and conclude with guidance on the application of models within the mine life cycle. The purpose of this paper is to better prepare stakeholders, including future modelers, mine managers, consultants, permitting agencies, land management agencies, regulators, research scientists, academics, and other interested parties, for the challenges of predicting and managing future pit lakes in un-mined areas

Bathymetric survey and estimation of the water balance of Lake ...

African Journals Online (AJOL)

Quantification of the water balance components and bathymetric survey is very crucial for sustainable management of lake waters. This paper focuses on the bathymetry and the water balance of the crater Lake Ardibo, recently utilized for irrigation. The bathymetric map of the lake is established at a contour interval of 10 ...

Preliminary results of hydrogeologic investigations Humboldt River Valley, Winnemucca, Nevada

Science.gov (United States)

Cohen, Philip M.

1964-01-01

Most of the ground water of economic importance and nearly all the ground water closely associated with the flow o# the Humboldt River in the. 40-mile reach near Winnemucca, Nev., are in unconsolidated sedimentary deposits. These deposits range in age from Pliocene to Recent and range in character from coarse poorly sorted fanglomerate to lacustrine strata of clay, silt, sand, and gravel. The most permeable deposit consists of sand and gravel of Lake Lahontan age--the so-called medial gravel unit--which is underlain and overlain by fairly impermeable silt and clay also of Lake Lahontan age. The ultimate source of nearly all the water in the study area is precpitation within the drainage basin of the Humboldt River. Much of this water reaches the study, area as flow or underflow of the Humboldt River and as underflow from other valleys tributary to the study area. Little if any flow from the tributary streams in the study area usually reaches the Humboldt River. Most of the tributary streamflow within the study area evaporates or is transpired by vegetation, but a part percolates downward through unconsolidated deposits of the alluvial fans flanking the mountains and move downgradient as ground-water underflow toward the Humboldt River. Areas that contribute significant amounts of ground-water underflow to. the valley of the Humboldt River within the study area are (1) the valley of the Humboldt River upstream from the study area, (2) the Pole Creek-Rock Creek area, (3) Paradise Valley, and (4) Grass Valley and the northwestern slope of the Sonoma Range. The total average underflow from these areas in the period 1949-61 was about 14,000-19,000 acre-feet per year. Much of this underflow discharged into the Humboldt River within the study area and constituted a large part of the base flow of the river. Streamflow in the Humboldt River increases substantially in the early spring, principally because of runoff to the river in the reaches upstream from the study area

THE WATER QUALITY FROM SAINT ANA LAKE

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M.VIGH

2013-03-01

Full Text Available Inside the Ciomad Massive appears a unique lake in Romania, with an exclusive precipitations alimentation regime. The lake’s origin and the morphometric elements, together with the touristic activity, determine the water’s quality and characteristics. Water status evaluation was realized using random samples taken between the years 2005 and 2010. Qualitative parameters indicate the existence of a clear water lake, belonging to ultra-oligotrophic faze. This is because the crater is covered with forest and the surface erosion is very poor. Also the aquatic vegetation is rare. From all analyzed indicators, only ammonium and total mineral nitrogen have higher values during last years. In the future, the lake needs a higher protection against water quality degradation.

Lake Chad, Chad, Africa

Science.gov (United States)

1992-01-01

Hydrologic and ecologic changes in the Lake Chad Basin are shown in this Oct 1992 photograph. In space photo documentation, Lake Chad was at its greatest area extent (25,000 sq. km.) during Gemini 9 in June 1966 (see S66-38444). Its reduction during the severe droughts from 1968 to 1974 was first noted during Skylab (1973-1974). After the drought began again in 1982, the lake reached its minimum extent (1,450 sq. km.) in Space Shuttle photographs taken in 1984 and 1985. In this STS-52 photograph, Lake Chad has begun to recover. The area of the open water and interdunal impoundments in the southern basin (the Chari River Basin) is estimated to be 1,900 to 2100 sq. km. Note the green vegetation in the valley of the K'Yobe flow has wetted the northern lake basin for the first time in several years. There is evidence of biomass burning south of the K'Yobe Delta and in the vegetated interdunal areas near the dike in the center of the lake. Also note the dark 'Green Line' of the Sahel (the g

Investigating Groundwater Depletion and Aquifer Degradation in Central Valley California from Space

Science.gov (United States)

Ojha, C.; Shirzaei, M.; Werth, S.; Argus, D. F.

2017-12-01

The Central Valley in California includes one of the world's largest and yet most stressed aquifer systems. The large demand for groundwater, accelerated by population growth and extreme droughts, has been depleting the region's groundwater resources for decades. However, the lack of dense monitoring networks and inaccurate information on geophysical aquifer response pose serious challenges to water management efforts in the area and put the groundwater at high risk. Here, we performed a joint analysis of large SAR interferometric data sets acquired by ALOS L-band satellite in conjunction with the groundwater level observations across the Central Valley. We used 420 L-band SAR images acquired on the ascending orbit track during period Dec 24, 2006 - Jan 1, 2010, and generated more than 1600 interferograms with a pixel size of 100 m × 100 m. We also use data from 1600 observational wells providing continuous measurements of groundwater level within the study period for our analysis. We find that in the south and near Tulare Lake, north of Tule and south of Kaweah basin in San Joaquin valley, the subsidence rate is greatest at up to 20-25 cm/yr, while in Sacramento Valley the subsidence rate is lower at 1-3 cm/yr. From the characterization of the elastic and inelastic storage coefficients, we find that Kern, Tule, Tulare, Kaweah and Merced basins in the San Joaquin Valley are more susceptible to permanent compaction and aquifer storage loss. Kern County shows 0.23%-1.8% of aquifer storage loss during the study period, and has higher percentage loss than adjacent basins such as Tule and Tulare Lake with 0.15%-1.2% and 0.2 %-1.5% loss, respectively. Overall, we estimate that the aquifers across the valley lost a total of 28 km3 of groundwater and 2% of their storage capacity during the study period. Our unique observational evidence including valley-wide estimate of mechanical properties of aquifers and model results will not only facilitate monitoring water deficits

New insights on water level variability for Lake Turkana for the past 15 ka and at 150 ka from relict beaches

Science.gov (United States)

Forman, S. L.; Wright, D.

2015-12-01

Relict beaches adjacent to Lake Turkana provide a record of water level variability for the Late Quaternary. This study focused on deciphering the geomorphology, sedimentology, stratigraphy and 14C chronology of strand plain sequences in the Kalokol and Lothagam areas. Nine >30 m oscillations in water level were documented between ca. 15 and 4 ka. The earliest oscillation between ca. 14.5 and 13 ka is not well constrained with water level to at least 70 m above the present surface and subsequently fell to at least 50 m. Lake level increased to ~ 90 m between ca. 11.2 and 10.4 ka, post Younger Dryas cooling. Water level fell by >30 m by 10.2 ka, with another potential rise at ca. 8.5 ka to >70 m above current level. Lake level regressed by > 40 m at 8.2 ka coincident with cooling in the equatorial Eastern Atlantic Ocean. Two major >70 m lake level oscillations centered at 6.6 and 5.2 ka may reflect enhanced convection with warmer sea surface temperatures in the Western Indian Ocean. The end of the African Humid Period occurred from ca. 8.0 to 4.5 ka and was characterized by variable lake level (± > 40 m), rather than one monotonic fall in water level. This lake level variability reflects a complex response to variations in the extent and intensity of the East and West African Monsoons near geographic and topographic limits within the catchment of Lake Turkana. Also, for this closed lake basin excess and deficits in water input are amplified with a cascading lake effect in the East Rift Valley and through the Chew Bahir Basin. The final regression from a high stand of > 90 m began at. 5.2 ka and water level was below 20 m by 4.5 ka; and for the remainder of the Holocene. This sustained low stand is associated with weakening of the West African Monsoon, a shift of the mean position of Congo Air Boundary west of the Lake Turkana catchment and with meter-scale variability in lake level linked to Walker circulation across the Indian Ocean. A surprising observation is

Impacts of population growth and economic development on water quality of a lake: case study of Lake Victoria Kenya water.

Science.gov (United States)

Juma, Dauglas Wafula; Wang, Hongtao; Li, Fengting

2014-04-01

Anthropogenic-induced water quality pollution is a major environmental problem in freshwater ecosystems today. As a result of this, eutrophication of lakes occurs. Population and economic development are key drivers of water resource pollution. To evaluate how growth in the riparian population and in the gross domestic product (GDP) with unplanned development affects the water quality of the lake, this paper evaluates Lake Victoria Kenyan waters basin. Waters quality data between 1990 and 2012 were analyzed along with reviews of published literature, papers, and reports. The nitrate-nitrogen (NO3-N), soluble phosphorus (PO4-P), chlorophyll a, and Secchi transparencies were evaluated as they are key water quality indicators. The NO3-N increased from 10 μg l(-1) in 1990 to 98 μg 1(-1) in 2008, while PO4-P increased from 4 μg l(-1) in 1990 to 57 μg l(-1) in 2008. The population and economic growth of Kenya are increasing with both having minimums in 1990 of 24.143 million people and 12.18 billion US dollars, to maximums in 2010 of 39.742 million people and 32.163 billion US dollars, respectively. A Secchi transparency is reducing with time, indicating an increasing pollution. This was confirmed by an increase in aquatic vegetation using an analysis of moderate resolution imaging spectroradiometer (MODIS) images of 2000 and 2012 of Kenyan waters. This study found that increasing population and GDP increases pollution discharge thus polluting lakes. One of major factors causing lake water pollution is the unplanned or poor waste management policy and service.

Water pollution in Rawal lake Islamabad (part-1)

International Nuclear Information System (INIS)

Ahmad, I.; Ali, S.; Tariq, M.; Ikram, M.

2001-01-01

Water pollution of Rawal Lake, one of the three major drinking water sources (21 MG) to Rawalpindi and Islamabad, by anionic pollutants is reported. Physicochemical analysis of water samples collected during September 1996 - January 1997, was carried out using ASTM and AOAC methods. Water samples from Rawal Lake and its tributaries were collected periodically and analyzed for pH, conductivity, turbidity, alkalinity, TDS, TSS, anions (chlorides, phosphates, nitrates, sulfates) and trace metals. (author)

Geology and hydrology between Lake McMillan and Carlsbad Springs, Eddy County, New Mexico

Science.gov (United States)

Cox, Edward Riley

1967-01-01

The hydrology of the Pecos River valley between Lake McMillan and Carlsbad Springs, Eddy County, N. Mex., is influenced by facies changes in rocks of Permian age. Water stored for irrigation leaks from Lake McMillan into evaporite rocks, principally gypsum, of the Seven Rivers Formation and from Lake Avalon into carbonate rocks of the Tansill Formation. This leakage returns to the Pecos River at Major Johnson Springs and Carlsbad Springs. The river has perennial flow between Major Johnson Springs and Lake Avalon, but it loses water into evaporite rocks of the Yates Formation in this reach. Ground-water movement is generally toward the Pecos River in aquifers in the Pecos River valley except in the Rustler Formation east of the river where it moves southeastward toward playas east of Lake Avalon. The chloride content of ground and surface waters indicates that surface water moves from some reaches of the Pecos River and from surface-storage reservoirs to aquifers and also indicates the degree of mixing of ground and surface waters. About 45,000 acre-feet of ground water is stored in highly permeable rocks in a 3-mile wide part of the Seven Rivers Formation between Lake McMillan and Major Johnson Springs. This water in storage comes from leakage from Lake McMillan and from alluvium north of the springs. The flow of Major Johnson Springs is derived from this aquifer. That part of the flow derived from the alluvium north of the springs averaged 13 cfs (cubic feet per second) from 1953 through 1959 ; about 8 cfs of this flow had not been previously measured at gaging stations on the Pecos River and its tributaries. The most favorable plans for increasing terminal storage of the Carlsbad Irrigation District are to construct a dam at the Brantley site (at the downstream end of Major Johnson Springs), or to use underground storage in the permeable Seven Rivers Formation between Lake McMillan and Major Johnson brings in conjunction with surface storage. To avoid excessive

Seasonal influence on water quality status of Temenggor Lake, Perak

International Nuclear Information System (INIS)

Wan Mohd Afiq Wan Abdul Khalik; Mohd Pauzi Abdullah; Mohd Pauzi Abdullah

2012-01-01

A study of the water quality in Temenggor Lake was conducted within two different seasons, namely wet season (November - January 2009) and dry season (March - July 2010). Thirteen sampling stations were selected representing open water body of the lake particularly surrounding Banding Island. Three depths layered sampling (surface, middle and bottom of lake) was performed at each sampling stations except in zone B. An average WQI for Temenggor Lake in wet season (90.49) is slightly higher than the average for dry season (88.87). This study indicates quite significant seasonal influence of rainfalls on environmental lake ecosystems by improving the quality through dilution effect on several parameters. Statistical analysis of two-way ANOVA test indicates that all measured parameters are affected by seasonal changes except for pH, turbidity, DO, BOD, oil and grease. Biochemical Oxygen Demand (BOD) and water hardness showed significant relationship with local community activities. Considering future development as eco tourism destination, the water quality of Temenggor Lake should be maintained thus some sort of integrated lake management system model on the integrated water resource management concept should be implemented. (author)

Continuous water-quality monitoring to improve lake management at Lake Mattamuskeet National Wildlife Refuge

Science.gov (United States)

Michelle Moorman; Tom Augspurger

2016-01-01

The U.S. Fish and Wildlife Service has partnered with U.S. Geological Survey to establish 2 continuous water-quality monitoring stations at Lake Mattamuskeet. Stations on the east and west side of the lake measure water level, clarity, dissolved oxygen, pH, temperature, salinity, and conductivity.

Distribution, sources and composition of antibiotics in sediment, overlying water and pore water from Taihu Lake, China

Energy Technology Data Exchange (ETDEWEB)

Xu, Jian [State Key Laboratory of Environmental Criteria and Risk Assessment, Chinese Research Academy of Environmental Sciences, Beijing 100012 (China); Laboratory of Riverine Ecological Conservation and Technology, Chinese Research Academy of Environmental Sciences, Beijing 100012 (China); Zhang, Yuan, E-mail: zhangyuan@craes.org.cn [State Key Laboratory of Environmental Criteria and Risk Assessment, Chinese Research Academy of Environmental Sciences, Beijing 100012 (China); Laboratory of Riverine Ecological Conservation and Technology, Chinese Research Academy of Environmental Sciences, Beijing 100012 (China); Zhou, Changbo [State Key Laboratory of Environmental Criteria and Risk Assessment, Chinese Research Academy of Environmental Sciences, Beijing 100012 (China); Guo, Changsheng; Wang, Dingming [State Key Laboratory of Environmental Criteria and Risk Assessment, Chinese Research Academy of Environmental Sciences, Beijing 100012 (China); Laboratory of Riverine Ecological Conservation and Technology, Chinese Research Academy of Environmental Sciences, Beijing 100012 (China); Du, Ping [State Key Laboratory of Environmental Criteria and Risk Assessment, Chinese Research Academy of Environmental Sciences, Beijing 100012 (China); Luo, Yi [College of Environmental Sciences and Engineering, Ministry of Education Key Laboratory of Pollution Processes and Environmental Criteria, Nankai University, Tianjin 300071 (China); Wan, Jun; Meng, Wei [State Key Laboratory of Environmental Criteria and Risk Assessment, Chinese Research Academy of Environmental Sciences, Beijing 100012 (China); Laboratory of Riverine Ecological Conservation and Technology, Chinese Research Academy of Environmental Sciences, Beijing 100012 (China)

2014-11-01

The occurrence of 15 antibiotics classified as sulphonamides, fluoroquinolones, macrolides, tetracyclines and trimethoprim in sediment, overlying water, and pore water matrices in Taihu Lake, China was studied. The total concentrations were from 4.1 μg/kg to 731 μg/kg, from 127 ng/L to 1210 ng/L, and from 1.5 ng/L to 216 ng/L in sediment, overlying water and pore water, respectively. Antibiotics in different locations originated from various sources, depending on human, agricultural and aquacultural activities. Composition analysis indicated that human-derived and animal-derived drugs significantly contributed to the total contamination of antibiotics in the lake, indicating the high complexity of contamination sources in Taihu Lake Basin. The in situ sediment–pore water partitioning coefficients were generally greater than sediment–overlying water partitioning coefficients, suggesting continuous inputs into the lake water. This study shows that antibiotics are ubiquitous in all compartments in Taihu Lake, and their potential hazards to the aquatic ecosystem need further investigation. - Highlights: • Antibiotics are ubiquitous in sediment, overlying water and pore water in Taihu Lake. • Antibiotics in Taihu Lake originated from human and nonhuman activities. • Ksp is higher than Ksw, indicating the continuous antibiotics input to lake water.

Distribution, sources and composition of antibiotics in sediment, overlying water and pore water from Taihu Lake, China

International Nuclear Information System (INIS)

Xu, Jian; Zhang, Yuan; Zhou, Changbo; Guo, Changsheng; Wang, Dingming; Du, Ping; Luo, Yi; Wan, Jun; Meng, Wei

2014-01-01

The occurrence of 15 antibiotics classified as sulphonamides, fluoroquinolones, macrolides, tetracyclines and trimethoprim in sediment, overlying water, and pore water matrices in Taihu Lake, China was studied. The total concentrations were from 4.1 μg/kg to 731 μg/kg, from 127 ng/L to 1210 ng/L, and from 1.5 ng/L to 216 ng/L in sediment, overlying water and pore water, respectively. Antibiotics in different locations originated from various sources, depending on human, agricultural and aquacultural activities. Composition analysis indicated that human-derived and animal-derived drugs significantly contributed to the total contamination of antibiotics in the lake, indicating the high complexity of contamination sources in Taihu Lake Basin. The in situ sediment–pore water partitioning coefficients were generally greater than sediment–overlying water partitioning coefficients, suggesting continuous inputs into the lake water. This study shows that antibiotics are ubiquitous in all compartments in Taihu Lake, and their potential hazards to the aquatic ecosystem need further investigation. - Highlights: • Antibiotics are ubiquitous in sediment, overlying water and pore water in Taihu Lake. • Antibiotics in Taihu Lake originated from human and nonhuman activities. • Ksp is higher than Ksw, indicating the continuous antibiotics input to lake water

Assessing Lake Level Variability and Water Availability in Lake Tana, Ethiopia using a Groundwater Flow Model and GRACE Satellite Data

Science.gov (United States)

Hasan, E.; Dokou, Z.; Kirstetter, P. E.; Tarhule, A.; Anagnostou, E. N.; Bagtzoglou, A. C.; Hong, Y.

2017-12-01

Lake Tana is the source of the Blue Nile and Ethiopia's largest natural buffer against seasonal variations of rainfall. Assessing the interactions between the lake level fluctuation, hydroclimatic variabilities and anthropogenic factors is essential to detect drought conditions and identify the role of human management in controlling the Lake water balance. Via an extended record of Total Water Storage (TWS) anomalies for the period 1960-2016, a water budget model for the lake water inflow/outflow was developed. Estimates of Lake Level Altimetry (LLA) based on in-situ and satellite altimetry were composited from 1960-2016 and compared to the extended TWS anomalies, the self-calibrated Palmer Drought Severity Index (scPDSI), the El Niño Southern Oscillation (ENSO) and the historical lake water levels and releases. In addition, the simulated lake levels and water budget from a coupled groundwater and lake model of the Lake Tana basin were compared to the above results. Combining the different approaches, the water budget of the lake can be monitored, the drought conditions can be identified and the role of human management in the lake can be determined. For instance, three major drought periods are identified, 1970 to 1977, 1979 to 1987 and 1990 to 1998, each succeeded with an interposed flooding related recovery year, i.e. 1978, 1988 and 1999. The drought/flooding events were attributed mainly to the ENSO interactions that resulted in lake level fluctuations. The period from 2002-2006 was associated with a remarkable decline of the lake level that was attributed partly in drought conditions and the full flow regulation of the Chara Chara weir at the lake outlet, initiated in 2001.

Ground-Water Flow Model for the Spokane Valley-Rathdrum Prairie Aquifer, Spokane County, Washington, and Bonner and Kootenai Counties, Idaho

Science.gov (United States)

Hsieh, Paul A.; Barber, Michael E.; Contor, Bryce A.; Hossain, Md. Akram; Johnson, Gary S.; Jones, Joseph L.; Wylie, Allan H.

2007-01-01

approximately 326 square miles. For the most part, the model extent coincides with the 2005 revised extent of the Spokane Valley-Rathdrum Prairie aquifer as defined in a previous report. However, the model excludes Spirit and Hoodoo Valleys because of uncertainties about the ground-water flow directions in those valleys and the degree of hydraulic connection between the valleys and northern Rathdrum Prairie. The SVRP aquifer is considered to be a single hydrogeologic unit except in Hillyard Trough and the Little Spokane River Arm. In those areas, a continuous clay layer divides the aquifer into an upper, unconfined unit and a lower, confined unit. The model includes all known components of inflows to and outflows from the aquifer. Inflows to the SVRP aquifer include (1) recharge from precipitation, (2) inflows from tributary basins and adjacent uplands, (3) subsurface seepage and surface overflows from lakes that border the aquifer, (4) flow from losing segments of the Spokane River to the aquifer, (5) return percolation from irrigation, and (6) effluent from septic systems. Outflows from the SVRP aquifer include (1) ground-water withdrawals from wells, (2) flow from the aquifer to gaining segments of the Spokane River, (3) aquifer discharge to the Little Spokane River, and (4) subsurface outflow from the lower unit at the western limit of the model area near Long Lake. These inflow and outflow components are represented in the model by using MODFLOW-2000 packages. The parameter-estimation program PEST was used to calibrate the SVRP aquifer model. PEST implements a nonlinear least-squares regression method to estimate model parameters so that the differences between measured and simulated quantities are minimized with respect to an optimal criterion. Calibration data include 1,573 measurements of water levels and 313 measurements of streamflow gains and losses along segments of the Spokane and Little Spokane Rivers. Model parameters estimated during calib

Protecting water resources from pollution in the Lake Badovc

Energy Technology Data Exchange (ETDEWEB)

Avdullahi, Sabri; Fejza, Islam; Tmava, Ahmet [Faculty of Geosciences and Technology, University of Prishtina, Str. Parku Industrial, 40000 Mitrovic, Republic of Kosova

2012-07-01

In recent years, the international community has witnessed incidence of climate variability and human activities. The objective of this paper is protecting water resources from pollution in the catchments area of Lake Badovc. The catchments area of the Lake Badovc has a size of 109 km² and the active storage volume of the lake is assessed to 26.4 Mill.m3. Around 28% of the total population of Municipality of Prishtina supply with drinking water from Lake Badovc. The hydrologic modelling system used, is HEC-HMS developed by the Hydrologic Engineering Centre of the US Corps of Engineers. The model is designed to simulate the rainfall-runoff processes of catchments areas and is applicable to a wide range of geographic areas.Water samples are taken from two streams reach Lake Badovc and from the lake in three different depths (5m, 10m and 15m) at different locations. Concerning the environment impact more than 140 interviews were conducted and questionnaires filled in the period October-November for Mramor area, concentrating on the most important issues: building, water supply, wastewater disposal and west disposal.

The major and trace element chemistry of fish and lake water within ...

African Journals Online (AJOL)

Chemical elements in lake water are incorporated into fish tissues through bioconcentration and biomagnification. Lake water and fish tissue samples from 23 lakes, located within 4 major South African catchments, were analysed to investigate the link between element concentrations in lake water and otolith, fin spine, ...

The Brine Shrimp Artemia Survives in Diluted Water of Lake Bunyampaka, an Inland Saline Lake in Uganda

Directory of Open Access Journals (Sweden)

Martin Sserwadda

2018-02-01

Full Text Available Ugandan aquaculture is in the process of development; however, it requires access to an affordable live food source, such as brine shrimp Artemia. This study fits within a broader feasibility study of domestic Artemia production in salt lakes. Since Uganda is a landlocked country, the only opportunity for live water food sources lies in the salt lakes in the west of the country. This study used saline water from one of these lakes, Lake Bunyampaka (salinity 72 mg L−1. Two Artemia strains, i.e., the Great Salt Lake strain, which is the dominant strain on the market, and the Vinh Chau strain, which is by far the most inoculated strain in the world, were assayed for their survival, growth, and reproduction in diluted Lake Bunyampaka water, using natural seawater as control. The organisms were fed live freshly cultured microalgae Tetraselmis suecica ad libitum. Our study revealed that the Vinh Chau strain performed especially well in Lake Bunyampaka water diluted to 50 g L−1. The data presented in this study generate the first useful information for the future inoculation of Artemia in Lake Bunyampaka in Uganda, and hence domestic Artemia production in the country; however, further larger-scale laboratory work, followed by field trials, is still needed.

Hydrogeologic Framework and Ground Water in Basin-Fill Deposits of the Diamond Valley Flow System, Central Nevada

Science.gov (United States)

Tumbusch, Mary L.; Plume, Russell W.

2006-01-01

The Diamond Valley flow system, an area of about 3,120 square miles in central Nevada, consists of five hydrographic areas: Monitor, Antelope, Kobeh, and Diamond Valleys and Stevens Basin. Although these five areas are in a remote part of Nevada, local government officials and citizens are concerned that the water resources of the flow system eventually could be further developed for irrigation or mining purposes or potentially for municipal use outside the study area. In order to better understand the flow system, the U.S. Geological Survey in cooperation with Eureka, Lander, and Nye Counties and the Nevada Division of Water Resources, is conducting a multi-phase study of the flow system. The principal aquifers of the Diamond Valley flow system are in basin-fill deposits that occupy structural basins comprised of carbonate rocks, siliciclastic sedimentary rocks, igneous intrusive rocks, and volcanic rocks. Carbonate rocks also function as aquifers, but their extent and interconnections with basin-fill aquifers are poorly understood. Ground-water flow in southern Monitor Valley is from the valley margins toward the valley axis and then northward to a large area of discharge by evapotranspiration (ET) that is formed south of a group of unnamed hills near the center of the valley. Ground-water flow from northern Monitor Valley, Antelope Valley, and northern and western parts of Kobeh Valley converges to an area of ground-water discharge by ET in central and eastern Kobeh Valley. Prior to irrigation development in the 1960s, ground-water flow in Diamond Valley was from valley margins toward the valley axis and then northward to a large discharge area at the north end of the valley. Stevens Basin is a small upland basin with internal drainage and is not connected with other parts of the flow system. After 40 years of irrigation pumping, a large area of ground-water decline has developed in southern Diamond Valley around the irrigated area. In this part of Diamond

Citizen and Satellite Measurements Used to Estimate Lake Water Storage Variations

Science.gov (United States)

Parkins, G.; Pavelsky, T.; Yelton, S.; Ghafoor, S. K.; Hossain, F.

2017-12-01

Of the roughly 20-40 million lakes in the world larger than 0.01 km2, perhaps a few thousand receive regular water level monitoring, and only approximately a thousand are included in the largest lake level databases. The prospect for on-the-ground, automated monitoring of a significant fraction of the world's lakes is not high given the considerable expense involved. In comparison to many other measurements, however, measuring lake water level is relatively simple under most conditions. A staff gauge installed in a lake, essentially a leveled ruler, can be read relatively simply by both experts and ordinary citizens. Reliable staff gauges cost far less than automated systems, making them an attractive alternative. However, staff gauges are only effective when they are regularly observed and when those observations are communicated to a central database. We have developed and tested a system for citizen scientists to monitor water levels in 15 lakes in Eastern North Carolina, USA and to easily report those measurements to our project team. We combine these citizen measurements with Landsat measurements of inundated area to track variations in lake water storage. Here, we present the resulting lake water level, inundation extent, and lake storage change time series and assess measurement accuracy. Our primary validation method for citizen-measured lake water levels is comparison with heights from pressure transducers also installed in all fifteen lakes. We use the validated results to understand spatial patterns in the lake hydrology of Eastern North Carolina. Finally, we consider the motivations of citizens who participate in the project and discuss the feedback they have provided regarding our measurement and communication systems.

LIMNOLOGY, LAKE BASINS, LAKE WATERS

Directory of Open Access Journals (Sweden)

Petre GÂŞTESCU

2009-06-01

Full Text Available Limnology is a border discipline between geography, hydrology and biology, and is also closely connected with other sciences, from it borrows research methods. Physical limnology (the geography of lakes, studies lake biotopes, and biological limnology (the biology of lakes, studies lake biocoenoses. The father of limnology is the Swiss scientist F.A. Forel, the author of a three-volume entitled Le Leman: monographie limnologique (1892-1904, which focuses on the geology physics, chemistry and biology of lakes. He was also author of the first textbook of limnology, Handbuch der Seenkunde: allgemeine Limnologie,(1901. Since both the lake biotope and its biohydrocoenosis make up a single whole, the lake and lakes, respectively, represent the most typical systems in nature. They could be called limnosystems (lacustrine ecosystems, a microcosm in itself, as the American biologist St.A. Forbes put it (1887.

Ikaite precipitation by mixing of shoreline springs and lake water, Mono Lake, California, USA

Science.gov (United States)

Bischoff, James L.; Stine, Scott; Rosenbauer, Robert J.; Fitzpatrick, John A.; Stafford, Thomas W., Jr.

1993-08-01

Metastable ikaite (CaCO 3·6H 2O) forms abundantly during winter months along the south shoreline of Mono Lake where shoreline springs mix with lake water. Ikaite precipitates because of its decreased solubility at low temperature and because of orthophosphate-ion inhibition of calcite and aragonite. During the spring some of the ikaite is transformed to anhydrous CaCO 3 and is incorporated into tufa, but most is dispersed by wave action into the lake where it reacts to form gaylussite (Na 2Ca(CO 3) 2· 5H 2O). Spring waters have low pH values, are dominantly Ca-Na-HCO 3, have low radiocarbon activities, and are mixtures of deep-seated geothermal and cold groundwaters. Chemical modeling reveals that precipitation of CaCO 3 can occur over a broad range of mixtures of spring and lake water with a maximum production occurring at 96% spring water and 4% lake water. Under these conditions all the Ca and a significant fraction of the CO 3 of the precipitate is spring supplied. A radiocarbon age of 19,580 years obtained on a natural ikaite sample supports this conclusion. With the springs supplying a large and probably variable portion of the carbonate, and with apparent 14C age of the carbonate varying from spring to spring, tufa of similar actual antiquity may yield significantly different 14C dates, making tufa at this location unsuitable for absolute age dating by the radiocarbon method.

Ice-dammed lateral lake and epishelf lake insights into Holocene dynamics of Marguerite Trough Ice Stream and George VI Ice Shelf, Alexander Island, Antarctic Peninsula

Science.gov (United States)

Davies, Bethan J.; Hambrey, Michael J.; Glasser, Neil F.; Holt, Tom; Rodés, Angél; Smellie, John L.; Carrivick, Jonathan L.; Blockley, Simon P. E.

2017-12-01

We present new data regarding the past dynamics of Marguerite Trough Ice Stream, George VI Ice Shelf and valley glaciers from Ablation Point Massif on Alexander Island, Antarctic Peninsula. This ice-free oasis preserves a geological record of ice stream lateral moraines, ice-dammed lakes, ice-shelf moraines and valley glacier moraines, which we dated using cosmogenic nuclide ages. We provide one of the first detailed sediment-landform assemblage descriptions of epishelf lake shorelines. Marguerite Trough Ice Stream imprinted lateral moraines against eastern Alexander Island at 120 m at Ablation Point Massif. During deglaciation, lateral lakes formed in the Ablation and Moutonnée valleys, dammed against the ice stream in George VI Sound. Exposure ages from boulders on these shorelines yielded ages of 13.9 to 9.7 ka. Following recession of the ice stream, George VI Ice Shelf formed in George VI Sound. An epishelf lake formed at 15-20 m asl in Ablation and Moutonnée valleys, dated from 9.4 to 4.6 ka, suggesting that the lake was stable and persistent for some 5000 years. Lake-level lowering occurred after this, with the lake level at 12 m at 3.1 ± 0.4 ka and at 5 m asl today. A readvance of the valley glaciers on Alexander Island at 4.4 ± 0.7 ka is recorded by valley glacier moraines overlying epishelf lake sediments. We speculate that the glacier readvance, which occurred during a period of warmth, may have been caused by a dynamic response of the glaciers to a lowering in surface elevation of George VI Ice Shelf.

Quality of drinking water from ponds in villages of Kolleru Lake region.

Science.gov (United States)

Rao, A S; Rao, P R; Rao, N S

2001-01-01

Kolleru Lake is the largest natural freshwater lake in the districts of East and West Godavari of Andhra Pradesh. The major population centres in the Kolleru Lake region are the 148 villages of which 50 bed villages and 98 belt villages. All bed and belt villages in lake region have at least one drinking water pond. Drinking water ponds are filled with lake water during monsoon season and directly supplied to the public throughout the year. The water samples were collected from village drinking water ponds in a year by covering three seasons and analysed for different physico-chemical parameters to assess the quality of drinking water.

The Model of Lake Operation in Water Transfer Projects Based on the Theory of Water- right

Science.gov (United States)

Bi-peng, Yan; Chao, Liu; Fang-ping, Tang

the lake operation is a very important content in Water Transfer Projects. The previous studies have not any related to water-right and water- price previous. In this paper, water right is divided into three parts, one is initialization waterright, another is by investment, and the third is government's water- right re-distribution. The water-right distribution model is also build. After analyzing the cost in water transfer project, a model and computation method for the capacity price as well as quantity price is proposed. The model of lake operation in water transfer projects base on the theory of water- right is also build. The simulation regulation for the lake was carried out by using historical data and Genetic Algorithms. Water supply and impoundment control line of the lake was proposed. The result can be used by south to north water transfer projects.

LAGOS-NE: a multi-scaled geospatial and temporal database of lake ecological context and water quality for thousands of US lakes

Science.gov (United States)

Bacon, Linda C; Beauchene, Michael; Bednar, Karen E; Bissell, Edward G; Boudreau, Claire K; Boyer, Marvin G; Bremigan, Mary T; Carpenter, Stephen R; Carr, Jamie W; Christel, Samuel T; Claucherty, Matt; Conroy, Joseph D; Downing, John A; Dukett, Jed; Filstrup, Christopher T; Funk, Clara; Gonzalez, Maria J; Green, Linda T; Gries, Corinna; Halfman, John D; Hamilton, Stephen K; Hanson, Paul C; Henry, Emily N; Herron, Elizabeth M; Hockings, Celeste; Jackson, James R; Jacobson-Hedin, Kari; Janus, Lorraine L; Jones, William W; Jones, John R; Keson, Caroline M; King, Katelyn B S; Kishbaugh, Scott A; Lathrop, Barbara; Latimore, Jo A; Lee, Yuehlin; Lottig, Noah R; Lynch, Jason A; Matthews, Leslie J; McDowell, William H; Moore, Karen E B; Neff, Brian P; Nelson, Sarah J; Oliver, Samantha K; Pace, Michael L; Pierson, Donald C; Poisson, Autumn C; Pollard, Amina I; Post, David M; Reyes, Paul O; Rosenberry, Donald O; Roy, Karen M; Rudstam, Lars G; Sarnelle, Orlando; Schuldt, Nancy J; Scott, Caren E; Smith, Nicole J; Spinelli, Nick R; Stachelek, Joseph J; Stanley, Emily H; Stoddard, John L; Stopyak, Scott B; Stow, Craig A; Tallant, Jason M; Thorpe, Anthony P; Vanni, Michael J; Wagner, Tyler; Watkins, Gretchen; Weathers, Kathleen C; Webster, Katherine E; White, Jeffrey D; Wilmes, Marcy K; Yuan, Shuai

2017-01-01

Abstract Understanding the factors that affect water quality and the ecological services provided by freshwater ecosystems is an urgent global environmental issue. Predicting how water quality will respond to global changes not only requires water quality data, but also information about the ecological context of individual water bodies across broad spatial extents. Because lake water quality is usually sampled in limited geographic regions, often for limited time periods, assessing the environmental controls of water quality requires compilation of many data sets across broad regions and across time into an integrated database. LAGOS-NE accomplishes this goal for lakes in the northeastern-most 17 US states. LAGOS-NE contains data for 51 101 lakes and reservoirs larger than 4 ha in 17 lake-rich US states. The database includes 3 data modules for: lake location and physical characteristics for all lakes; ecological context (i.e., the land use, geologic, climatic, and hydrologic setting of lakes) for all lakes; and in situ measurements of lake water quality for a subset of the lakes from the past 3 decades for approximately 2600–12 000 lakes depending on the variable. The database contains approximately 150 000 measures of total phosphorus, 200 000 measures of chlorophyll, and 900 000 measures of Secchi depth. The water quality data were compiled from 87 lake water quality data sets from federal, state, tribal, and non-profit agencies, university researchers, and citizen scientists. This database is one of the largest and most comprehensive databases of its type because it includes both in situ measurements and ecological context data. Because ecological context can be used to study a variety of other questions about lakes, streams, and wetlands, this database can also be used as the foundation for other studies of freshwaters at broad spatial and ecological scales. PMID:29053868

LAGOS-NE: a multi-scaled geospatial and temporal database of lake ecological context and water quality for thousands of US lakes.

Science.gov (United States)

Soranno, Patricia A; Bacon, Linda C; Beauchene, Michael; Bednar, Karen E; Bissell, Edward G; Boudreau, Claire K; Boyer, Marvin G; Bremigan, Mary T; Carpenter, Stephen R; Carr, Jamie W; Cheruvelil, Kendra S; Christel, Samuel T; Claucherty, Matt; Collins, Sarah M; Conroy, Joseph D; Downing, John A; Dukett, Jed; Fergus, C Emi; Filstrup, Christopher T; Funk, Clara; Gonzalez, Maria J; Green, Linda T; Gries, Corinna; Halfman, John D; Hamilton, Stephen K; Hanson, Paul C; Henry, Emily N; Herron, Elizabeth M; Hockings, Celeste; Jackson, James R; Jacobson-Hedin, Kari; Janus, Lorraine L; Jones, William W; Jones, John R; Keson, Caroline M; King, Katelyn B S; Kishbaugh, Scott A; Lapierre, Jean-Francois; Lathrop, Barbara; Latimore, Jo A; Lee, Yuehlin; Lottig, Noah R; Lynch, Jason A; Matthews, Leslie J; McDowell, William H; Moore, Karen E B; Neff, Brian P; Nelson, Sarah J; Oliver, Samantha K; Pace, Michael L; Pierson, Donald C; Poisson, Autumn C; Pollard, Amina I; Post, David M; Reyes, Paul O; Rosenberry, Donald O; Roy, Karen M; Rudstam, Lars G; Sarnelle, Orlando; Schuldt, Nancy J; Scott, Caren E; Skaff, Nicholas K; Smith, Nicole J; Spinelli, Nick R; Stachelek, Joseph J; Stanley, Emily H; Stoddard, John L; Stopyak, Scott B; Stow, Craig A; Tallant, Jason M; Tan, Pang-Ning; Thorpe, Anthony P; Vanni, Michael J; Wagner, Tyler; Watkins, Gretchen; Weathers, Kathleen C; Webster, Katherine E; White, Jeffrey D; Wilmes, Marcy K; Yuan, Shuai

2017-12-01

Understanding the factors that affect water quality and the ecological services provided by freshwater ecosystems is an urgent global environmental issue. Predicting how water quality will respond to global changes not only requires water quality data, but also information about the ecological context of individual water bodies across broad spatial extents. Because lake water quality is usually sampled in limited geographic regions, often for limited time periods, assessing the environmental controls of water quality requires compilation of many data sets across broad regions and across time into an integrated database. LAGOS-NE accomplishes this goal for lakes in the northeastern-most 17 US states.LAGOS-NE contains data for 51 101 lakes and reservoirs larger than 4 ha in 17 lake-rich US states. The database includes 3 data modules for: lake location and physical characteristics for all lakes; ecological context (i.e., the land use, geologic, climatic, and hydrologic setting of lakes) for all lakes; and in situ measurements of lake water quality for a subset of the lakes from the past 3 decades for approximately 2600-12 000 lakes depending on the variable. The database contains approximately 150 000 measures of total phosphorus, 200 000 measures of chlorophyll, and 900 000 measures of Secchi depth. The water quality data were compiled from 87 lake water quality data sets from federal, state, tribal, and non-profit agencies, university researchers, and citizen scientists. This database is one of the largest and most comprehensive databases of its type because it includes both in situ measurements and ecological context data. Because ecological context can be used to study a variety of other questions about lakes, streams, and wetlands, this database can also be used as the foundation for other studies of freshwaters at broad spatial and ecological scales. © The Author 2017. Published by Oxford University Press.

LAGOS-NE: a multi-scaled geospatial and temporal database of lake ecological context and water quality for thousands of US lakes

Science.gov (United States)

Soranno, Patricia A.; Bacon, Linda C.; Beauchene, Michael; Bednar, Karen E.; Bissell, Edward G.; Boudreau, Claire K.; Boyer, Marvin G.; Bremigan, Mary T.; Carpenter, Stephen R.; Carr, Jamie W.; Cheruvelil, Kendra S.; Christel, Samuel T.; Claucherty, Matt; Collins, Sarah M.; Conroy, Joseph D.; Downing, John A.; Dukett, Jed; Fergus, C. Emi; Filstrup, Christopher T.; Funk, Clara; Gonzalez, Maria J.; Green, Linda T.; Gries, Corinna; Halfman, John D.; Hamilton, Stephen K.; Hanson, Paul C.; Henry, Emily N.; Herron, Elizabeth M.; Hockings, Celeste; Jackson, James R.; Jacobson-Hedin, Kari; Janus, Lorraine L.; Jones, William W.; Jones, John R.; Keson, Caroline M.; King, Katelyn B.S.; Kishbaugh, Scott A.; Lapierre, Jean-Francois; Lathrop, Barbara; Latimore, Jo A.; Lee, Yuehlin; Lottig, Noah R.; Lynch, Jason A.; Matthews, Leslie J.; McDowell, William H.; Moore, Karen E.B.; Neff, Brian; Nelson, Sarah J.; Oliver, Samantha K.; Pace, Michael L.; Pierson, Donald C.; Poisson, Autumn C.; Pollard, Amina I.; Post, David M.; Reyes, Paul O.; Rosenberry, Donald; Roy, Karen M.; Rudstam, Lars G.; Sarnelle, Orlando; Schuldt, Nancy J.; Scott, Caren E.; Skaff, Nicholas K.; Smith, Nicole J.; Spinelli, Nick R.; Stachelek, Joseph J.; Stanley, Emily H.; Stoddard, John L.; Stopyak, Scott B.; Stow, Craig A.; Tallant, Jason M.; Tan, Pang-Ning; Thorpe, Anthony P.; Vanni, Michael J.; Wagner, Tyler; Watkins, Gretchen; Weathers, Kathleen C.; Webster, Katherine E.; White, Jeffrey D.; Wilmes, Marcy K.; Yuan, Shuai

2017-01-01

Understanding the factors that affect water quality and the ecological services provided by freshwater ecosystems is an urgent global environmental issue. Predicting how water quality will respond to global changes not only requires water quality data, but also information about the ecological context of individual water bodies across broad spatial extents. Because lake water quality is usually sampled in limited geographic regions, often for limited time periods, assessing the environmental controls of water quality requires compilation of many data sets across broad regions and across time into an integrated database. LAGOS-NE accomplishes this goal for lakes in the northeastern-most 17 US states.LAGOS-NE contains data for 51 101 lakes and reservoirs larger than 4 ha in 17 lake-rich US states. The database includes 3 data modules for: lake location and physical characteristics for all lakes; ecological context (i.e., the land use, geologic, climatic, and hydrologic setting of lakes) for all lakes; and in situ measurements of lake water quality for a subset of the lakes from the past 3 decades for approximately 2600–12 000 lakes depending on the variable. The database contains approximately 150 000 measures of total phosphorus, 200 000 measures of chlorophyll, and 900 000 measures of Secchi depth. The water quality data were compiled from 87 lake water quality data sets from federal, state, tribal, and non-profit agencies, university researchers, and citizen scientists. This database is one of the largest and most comprehensive databases of its type because it includes both in situ measurements and ecological context data. Because ecological context can be used to study a variety of other questions about lakes, streams, and wetlands, this database can also be used as the foundation for other studies of freshwaters at broad spatial and ecological scales.

Hydrologic and Water-Quality Characterization and Modeling of the Onondaga Lake Basin, Onondaga County, New York

Science.gov (United States)

Coon, William F.; Reddy, James E.

2008-01-01

were generated for known sources of these constituents, including the Tully Valley mudboils (flow and sediment), Otisco Lake (flow and nutrients), the Marcellus wastewater-treatment plant (flow and nutrients), and springs from carbonate bedrock (flow). Runoff from the impervious sewered areas of the City of Syracuse was adjusted for the quantity that was treatable at the county wastewater-treatment plant; the excess flows were routed to nearby streams through combined-sanitary-and-storm-sewer overflows. The mitigative effects that the Onondaga Reservoir and Otisco Lake were presumed to have on loads of sediment and particulate constituents were simulated by adjustment of parameter values that controlled sediment settling rates, deposition, and scour in the reservoir and lake. Graphical representations of observed and simulated data, and relevant statistics, were compared to assess model performance. Simulated daily and monthly streamflows were rated ?very good? (within 10 percent of observed flows) at all calibration sites, except Onondaga Creek at Cardiff, which was rated ?fair? (10?15 percent difference). Simulations of monthly average water temperatures were rated ?very good? (within 7 percent of observed temperatures) at all sites. No observed data were available by which to directly assess the model?s simulation of suspended sediment loads. Available measured total suspended solids data provided an indirect means of comparison but, not surprisingly, yielded only ?fair? to ?poor? ratings (greater than 30 percent difference) for simulated monthly sediment loads at half the water-quality calibration sites. Simulations of monthly orthophosphate loads ranged from ?very good? (within 15 percent of measured loads) at three sites to ?poor? (greater than 35 percent difference) at one site; simulations of ammonia nitrogen loads ranged from ?very good? at one site to ?fair? (25?35 percent difference) at two sites. Simulations of monthly total phosphorus, nitrate, and or

UMTRA project water sampling and analysis plan, Monument Valley, Arizona

International Nuclear Information System (INIS)

1994-04-01

The Monument Valley Uranium Mill Tailings Remedial Action (UMTRA) Project site in Cane Valley is a former uranium mill that has undergone surface remediation in the form of tailings and contaminated materials removal. Contaminated materials from the Monument Valley (Arizona) UMTRA Project site have been transported to the Mexican Hat (Utah) UMTRA Project site for consolidation with the Mexican Hat tailings. Tailings removal was completed in February 1994. Three geologic units at the site contain water: the unconsolidated eolian and alluvial deposits (alluvial aquifer), the Shinarump Conglomerate (Shinarump Member), and the De Chelly Sandstone. Water quality analyses indicate the contaminant plume has migrated north of the site and is mainly in the alluvial aquifer. An upward hydraulic gradient in the De Chelly Sandstone provides some protection to that aquifer. This water sampling and analysis plan recommends sampling domestic wells, monitor wells, and surface water in April and September 1994. The purpose of sampling is to continue periodic monitoring for the surface program, evaluate changes to water quality for site characterization, and provide data for the baseline risk assessment. Samples taken in April will be representative of high ground water levels and samples taken in September will be representative of low ground water levels. Filtered and nonfiltered samples will be analyzed for plume indicator parameters and baseline risk assessment parameters

Ground water in Fountain and Jimmy Camp Valleys, El Paso County, Colorado with a section on Computations of drawdowns caused by the pumping of wells in Fountain Valley

Science.gov (United States)

Jenkins, Edward D.; Glover, Robert E.

1964-01-01

The part of Fountain Valley considered in this report extends from Colorado Springs to the Pueblo County line. It is 23 miles long and has an area of 26 square miles. The part of Jimmy Camp Valley discussed is 11 miles long and has an area of 9 square miles. The topography is characterized by level flood plains and alluvial terraces that parallel the valley and by rather steep hills along the valley sides. The climate is semiarid, average annual precipitation being about 13 inches. Farming and stock raising are the principal occupations in the valleys; however, some of the agricultural land near Colorado Springs is being used for housing developments. The Pierre Shale and alluvium underlie most of the area, and mesa gravel caps the shale hills adjacent to Fountain Valley. The alluvium yields water to domestic, stock, irrigation, and public-supply wells and is capable of yielding large quantities of water for intermittent periods. Several springs issue along the sides of the valley at the contact of the mesa gravel and the underlying Pierre Shale. The water table ranges in depth from less than 10 feet along the bottom lands to about 80 feet along the sides of the valleys; the saturated thickness ranges from less than a foot to about 50 feet. The ground-water reservoir in Fountain Valley is recharged by precipitation that falls within the area, by percolation from Fountain Creek, which originates in the Pikes Peak, Monument Valley, and Rampart Range areas, and by seepage from irrigation water. This reservoir contains about 70,000 acre-feet of ground water in storage. The ground-water reservoir in Jimmy Camp Valley is recharged from precipitation that falls within the area, by percolation from Jimmy Camp Creek during periods of streamflow, and by seepage from irrigation water. The Jimmy Camp ground-water reservoir contains about 25,000 acre-feet of water in storage. Ground water is discharged from the area by movement to the south, by evaporation and transpiration in

Nitrogen Dynamics Variation in Overlying Water of Jinshan Lake, China

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Xiaohong Zhou

2015-01-01

Full Text Available Jinshan Lake is a famous urban landscape lake with approximately 8.8 km2 water area, which is located on the north of Zhenjiang, of Jiangsu Province, China. Eighteen sampled sites were selected and overlying water was sampled from 2013 to 2014 to study the seasonal and spatial variation of nitrogen in overlying water of Jinshan Lake. Results showed that physicochemical characteristics of temperature, pH, and DO showed high seasonal variation, whereas they had no significant spatial differences in the 18 sampling points (P>0.05 in overlying water of Jinshan Lake. Nitrogen concentrations showed strong seasonal variation trends. The ranked order of TN was as follows: spring > summer > autumn > winter; the order of NH4+-N was as follows: spring > autumn > summer > winter, whereas NO3--N concentrations revealed an inverse seasonal pattern, with maxima occurring in winter and minimal values occurring in spring. Nitrogen concentrations had dramatic spatial changes in 18 sampling points of Jinshan Lake. Physicochemical parameter difference, domestic wastes pollution, and rainfall runoff source may have led to seasonal and spatial fluctuation variations of nitrogen in overlying water of Jinshan Lake, China.

Using Snow Fences to Augument Fresh Water Supplies in Shallow Arctic Lakes

Energy Technology Data Exchange (ETDEWEB)

Stuefer, Svetlana

2013-03-31

This project was funded by the U.S. Department of Energy, National Energy Technology Laboratory (NETL) to address environmental research questions specifically related to Alaska's oil and gas natural resources development. The focus of this project was on the environmental issues associated with allocation of water resources for construction of ice roads and ice pads. Earlier NETL projects showed that oil and gas exploration activities in the U.S. Arctic require large amounts of water for ice road and ice pad construction. Traditionally, lakes have been the source of freshwater for this purpose. The distinctive hydrological regime of northern lakes, caused by the presence of ice cover and permafrost, exerts influence on lake water availability in winter. Lakes are covered with ice from October to June, and there is often no water recharge of lakes until snowmelt in early June. After snowmelt, water volumes in the lakes decrease throughout the summer, when water loss due to evaporation is considerably greater than water gained from rainfall. This balance switches in August, when air temperature drops, evaporation decreases, and rain (or snow) is more likely to occur. Some of the summer surface storage deficit in the active layer and surface water bodies (lakes, ponds, wetlands) is recharged during this time. However, if the surface storage deficit is not replenished (for example, precipitation in the fall is low and near‐surface soils are dry), lake recharge is directly affected, and water availability for the following winter is reduced. In this study, we used snow fences to augment fresh water supplies in shallow arctic lakes despite unfavorable natural conditions. We implemented snow‐control practices to enhance snowdrift accumulation (greater snow water equivalent), which led to increased meltwater production and an extended melting season that resulted in lake recharge despite low precipitation during the years of the experiment. For three years (2009

Behavior of chlorine in lake water

International Nuclear Information System (INIS)

Sriraman, A.K.

2006-01-01

Water from monsoon fed Sagre lake is being used as a source of raw water for Tarapur Atomic Power Station (TAPS--1 and 2). The raw water from the lake is initially pumped to Sagre water treatment plant (SWTP) operated by Maharashtra Industrial Development Corporation (MIDC) from where, the processed water is sent to cater the needs of both the units of TAPS-1 and 2, townships of TAPS and MIDC, and the nearby villages. At the SWTP the raw water is treated with alum to remove the turbidity, filtered and chlorinated using bleaching powder. All these years the raw water is chlorinated in such a way whereby a residual chlorine level of 0.5-1.0 mg/l, is maintained at the outlet of water treatment plant. The adequacy of the current chlorination practice was investigated, at the request of the NPC-500 MWe group during 1990, so that the future requirements of raw water for TAPP-3 and 4, can be met from the expanded SWTP. In this connection experiments on chlorine dose -- residual chlorine relationship and the decay pattern of chlorine with time was carried out in the lake water (with low value of total dissolved solids and total hardness 3 sample at the site. The total bacterial count in the raw water observed to be 10 7 counts/ml originally came down to 10 3 counts/ml at the end of one-hour exposure time to chlorine. It was found that the chlorine demand of the water was around 6 mg/l. In addition Jar test to evaluate the aluminum dose was also carried out. Based on these experiments a chlorine dose of 6 mg/l for one hour contact time was arrived at. The experimental findings were in agreement with the current chlorination practices. (author)

The influence of water quality on the reuse of lignite-derived waters in the Latrobe Valley, Australia

Energy Technology Data Exchange (ETDEWEB)

C.J. Butler; A.M. Green; L. Chaffee [Monash University, Churchill, Vic. (Australia). CRC for Clean Power from Lignite, School of Applied Sciences and Engineering

2005-03-01

Mechanical Thermal Expression (MTE), a novel non-evaporative brown coal (lignite) dewatering process, is being developed to increase the efficiency of power stations in the Latrobe Valley (Victoria, Australia). A by-product of this process is a large volume (potentially 20 giga liters per annum) of product water stream. This paper examines water quality requirements for reuse and disposal within the Latrobe Valley and their compatibility with MTE process water. It has been established that remediation of this water will be required and that the maintenance of environmental flows in surface waters would be the most suitable use for the remediated water.

Distribution of fallout plutonium in the waters of the lower Great Lakes

International Nuclear Information System (INIS)

Alberts, J.J.; Wahlgren, M.A.; Nelson, D.M.

1976-01-01

The concentrations of fallout 239 240 Pu in the surface waters from all the Great Lakes were slightly lower in 1976 samples than in those from 1973. The same trend of higher concentrations in the surface waters of the upper lakes as in the surface waters of the lower lakes was observed for both years. In addition, the 239 240 Pu concentration in samples of deep water collected during the summer of 1976 was higher than in the surface waters but was similar to the surface water values of the 1973 spring samples. This observation is significant in that it suggests that the surface waters of all the Great Lakes undergo a seasonal decrease in plutonium concentration similar to that already observed in Lake Michigan

Influence of flood risk management measures on socio-economic and ecological vulnerabilities in a large water system - A case study of Lake Vänern and the Göta älv River, Sweden

Science.gov (United States)

Nyberg, L.; Blumenthal, B.; Johansson, M.

2009-04-01

An important feature of flood risk management is to integrate ecological, economical and social aspects on prevention and mitigation measures. Protective measures could potentially be in conflict with sound functions of ecosystems or cause conflicts in upstream/downstream relations. A case study of a large water system in south-western Sweden - Lake Vänern and the Göta älv River - was used to analyse the relation between socio-economic and ecological vulnerabilities and to identify opposing interests regarding water level fluctuations and high-water-level situations in the lake. Lake Vänern with its area of 5,500 km2 is the largest lake in Sweden and within the European Union. The Göta älv River runs from the lake outlet 90 km down to the sea at Gothenburg. The total catchment area upstream of the river mouth is 51,000 km2. Vänern and Göta älv are used for hydropower production, shipping, tourism, fishing, drinking water supply, as waste water recipient, etc. The risk system is complex with flood risks in the lake and in Gothenburg which are connected to landslide risks and industrial risks in the river valley, and where the drinking water supply for 700,000 persons in the Gothenburg region is at stake. Because of the landslide risks along the downstream river, the water discharge from Lake Vänern is limited. During periods of high inflow to the lake, situations of high water-levels last at least for six months. Substantial increases in precipitation during the 21st century, according to IPCC, will give a corresponding increase in flood risks.

Determination of Water Quality Parameters in Sivas - Kurugöl Lake

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Ekrem Mutlu

2013-12-01

Full Text Available Kurugöl Lake; Sivas province Hafik county Kurugöl village located within the boundaries of Sivas province, 54 km, Hafik the town 24 miles away, an area of 8.9 ha altitude of 1362 m, an average depth of 3.4 - 4 m with gypsum plateau on the bottom of the boiling water along with rainfall and snowmelt with the lake is fed naturally. Kurugöl (Hafik - Sivas waters of Lake of the physical and chemical properties during the year changes occurring determining water quality characteristics to reveal the pollution levels are determined, living life in terms of the availability of the detection, water pollution and control regulations by the lake water classification and fishing activities, compliance with were identified. The inland lake in Kurugöl (SKKY according to the classification of water resources in accordance with the parameters measured I-III water quality varies from class.

Spatial variation in nutrient and water color effects on lake chlorophyll at macroscales

Science.gov (United States)

Fergus, C. Emi; Finley, Andrew O.; Soranno, Patricia A.; Wagner, Tyler

2016-01-01

The nutrient-water color paradigm is a framework to characterize lake trophic status by relating lake primary productivity to both nutrients and water color, the colored component of dissolved organic carbon. Total phosphorus (TP), a limiting nutrient, and water color, a strong light attenuator, influence lake chlorophyll a concentrations (CHL). But, these relationships have been shown in previous studies to be highly variable, which may be related to differences in lake and catchment geomorphology, the forms of nutrients and carbon entering the system, and lake community composition. Because many of these factors vary across space it is likely that lake nutrient and water color relationships with CHL exhibit spatial autocorrelation, such that lakes near one another have similar relationships compared to lakes further away. Including this spatial dependency in models may improve CHL predictions and clarify how well the nutrient-water color paradigm applies to lakes distributed across diverse landscape settings. However, few studies have explicitly examined spatial heterogeneity in the effects of TP and water color together on lake CHL. In this study, we examined spatial variation in TP and water color relationships with CHL in over 800 north temperate lakes using spatially-varying coefficient models (SVC), a robust statistical method that applies a Bayesian framework to explore space-varying and scale-dependent relationships. We found that TP and water color relationships were spatially autocorrelated and that allowing for these relationships to vary by individual lakes over space improved the model fit and predictive performance as compared to models that did not vary over space. The magnitudes of TP effects on CHL differed across lakes such that a 1 μg/L increase in TP resulted in increased CHL ranging from 2–24 μg/L across lake locations. Water color was not related to CHL for the majority of lakes, but there were some locations where water color had a

What caused the decline of China's largest freshwater lake? Attribution analysis on Poyang Lake water level variations in recent years

Science.gov (United States)

Ye, Xuchun; Xu, Chong-Yu; Zhang, Qi

2017-04-01

In recent years, dramatic decline of water level of the Poyang Lake, China's largest freshwater lake, has raised wide concerns about the water security and wetland ecosystem. This remarkable hydrological change coincided with several factors like the initial operation of the Three Gorges Dam (TGD) in 2003, the big change of lake bottom topography due to extensive sand mining in the lake since 2000, and also climate change and other human activities in the Yangtze River basin may add to this complexity. Questions raised to what extent that the lake hydrological changes is caused by climate change and/or human activities. In this study, quantitative assessment was conducted to clarify the magnitude and mechanism of specific influencing factors on recent lake decline (2003-2014), with reference to the period of 1980-1999. The attempts were achieved through the reconstruction of lake water level scenarios by the framework of neural network. Major result indicates that the effect of lake bottom topography change due to sand mining activities has became the dominant factor for the recent lake decline, especially in winter season with low water level. However, the effect of TGD regulation shows strong seasonal features, its effect can accounts for 33%-42% of the average water level decline across the lake during the impoundment period of September-October. In addition, the effect of climate change and other human activities over the Yangtze River basin needs to be highly addressed, which is particularly prominent on reducing lake water level during the summer flood season and autumn recession period. The result also revealed that due to different mechanism, the responses of the lake water level to the three influencing factors are not consistent and show great spatial and temporal differences.

Impact of water-level changes to aquatic vegetation in small oligotrophic lakes

Directory of Open Access Journals (Sweden)

Egert VANDEL

2016-06-01

Full Text Available This study demonstrates the effect of drastic water-level changes to the aquatic vegetation in three small oligotrophic lakes situated in Kurtna Kame Field in north-eastern Estonia. The area holds around 40 lakes in 30 km2 of which 18 lakes are under protection as Natura Habitat lakes (Natura 2000 network. The area is under a strong human impact as it is surrounded by oil shale mines, sand quarry, peat harvesting field etc. The most severe impact comes from the groundwater intake established in 1972 in the vicinity of three studied lakes. The exploitation of groundwater led to drastic water-level drops. In 1980s the water-level drops were measured to be up to 3 to 4 meters compared to the levels of 1946. Lake Martiska and Lake Kuradijärv were severely affected and only 29% and 45% of lake area respectively and 21% of initial volume remained. Both lakes were described as oligotrophic lakes before severe human impact and held characteristic macrophytes such as Isoëtes lacustris L., Sparganium angustifolium Michx and Lobelia dortmanna L. As the water level declined the lakes lost their rare characteristic species and can now be described more as a meso- or even eutrophic lakes. When the volume of groundwater abstraction decreased in the 1990s the water levels started to recover but did not reach the natural levels of pre-industrialized era. Also the vegetation did not show any signs of recovery. In 2012 the pumping rates increased again causing a new rapid decline in water levels which almost exceed the previous minimum levels. The water-level monitoring alongside with the macrophyte monitoring data gives us a good case study on how the long term abrupt water-level changes can affect the aquatic vegetation

Evaluation of Water Quality in Shallow Lakes, Case Study of Lake Uluabat

Directory of Open Access Journals (Sweden)

Saadet İLERİ

2014-04-01

Full Text Available Lake Uluabat, located 20 km south of the Marmara Sea, between 42° 12' North latitude, 28° 40'East longitude and is located in the province of Bursa. The Lake is one of the richest lakes in terms of aquatic plants besides fish and bird populations in Turkey. In this study, water quality of the Lake was monitored from June 2008 to May 2009 during the 12 month period with the samples taken from 8 points in the lake and spatial and temporal variations of the parameters were examined. pH, temperature (T, electrical conductivity (EC, dissolved oxygen (DO, suspended solids (SS, secchi depth (SD, water level (WL, nitrate nitrogen (NO3-N, total nitrogen (TN, phosphate-phosphorus (PO4-P, total phosphorus (TP, alkalinity, chemical oxygen demand (COD and chlorophyll-a (Chl-a were the monitoring parameters. As a result, concentrations of the parameters were found at high levels especially the 1st, 4th, 5th, and 8th stations and temporally were found at high levels often in the summer. According to the results of analysis of variance, regional and temporal variations of all parameters were found important except SS and NO3-N

Analysis of geophysical well logs from the Mariano Lake-Lake Valley drilling project, San Juan Basin, Northwestern New Mexico

International Nuclear Information System (INIS)

Scott, J.H.

1986-01-01

Geophysical well logs were obtained in eight deep holes drilled and cored by the U.S. Geological Survey to examine the geology of the Mariano Lake-Lake Valley area in the southern part of the San Juan basin, New Mexico. The logs were made to determine the petrophysical properties of the rocks penetrated by the holes, to aid in making stratigraphic correlations between the holes, and to estimate the grade of uranium enrichment in mineralized zones. The logs can be divided into six categories-nuclear, electric, sonic, magnetic, dipmeter, and borehole conditions. Examples of these logs are presented and related to lithological and petrophysical properties of the cores recovered. Gamma-ray and prompt fission neutron logs were used to estimate uranium grade in mineralized zones. Resistivity and spontaneous potential logs were used to make stratigraphic correlations between drill holes and to determine the variability of the sandstone:mudstone ratios of the major sedimentary units. In one drill hole a dipmeter log was used to estimate the direction of sediment transport of the fluvial host rock. Magnetic susceptibility logs provided supportive information for a laboratory study of magnetic mineral alteration in drill cores. This study was used to infer the geochemical and hydrologic environment associated with uranium deposition in the project area

Ground-water discharge determined from measurements of evapotranspiration, other available hydrologic components, and shallow water-level changes, Oasis Valley, Nye County, Nevada

International Nuclear Information System (INIS)

Reiner, S.R.; Laczniak, R.J.; DeMeo, G.A.; Smith LaRue, J.; Elliott, P.E.; Nylund, W.E.; Fridrich, C.J.

2002-01-01

Oasis Valley is an area of natural ground-water discharge within the Death Valley regional ground-water flow system of southern Nevada and adjacent California. Ground water discharging at Oasis Valley is replenished from inflow derived from an extensive recharge area that includes the northwestern part of the Nevada Test Site (NTS). Because nuclear testing has introduced radionuclides into the subsurface of the NTS, the U.S. Department of Energy currently is investigating the potential transport of these radionuclides by ground water flow. To better evaluate any potential risk associated with these test-generated contaminants, a number of studies were undertaken to accurately quantify discharge from areas downgradient in the regional ground-water flow system from the NTS. This report refines the estimate of ground-water discharge from Oasis Valley. Ground-water discharge from Oasis Valley was estimated by quantifying evapotranspiration (ET), estimating subsurface outflow, and compiling ground-water withdrawal data. ET was quantified by identifying areas of ongoing ground-water ET, delineating areas of ET defined on the basis of similarities in vegetation and soil-moisture conditions and computing ET rates for each of the delineated areas. A classification technique using spectral-reflectance characteristics determined from satellite imagery acquired in 1992 identified eight unique areas of ground-water ET. These areas encompass about 3,426 acres of sparsely to densely vegetated grassland, shrubland, wetland, and open water. Annual ET rates in Oasis Valley were computed with energy-budget methods using micrometeorological data collected at five sites. ET rates range from 0.6 foot per year in a sparse, dry saltgrass environment to 3.1 feet per year in dense meadow vegetation. Mean annual ET from Oasis Valley is estimated to be about 7,800 acre-feet. Mean annual ground-water discharge by ET from Oasis Valley, determined by removing the annual local precipitation

Hydrology, water quality, trophic status, and aquatic plants of Fowler Lake, Wisconsin

Science.gov (United States)

Hughes, P.E.

1993-01-01

The U.S. Geological Survey, in cooperation with the Fowler Lake Management District, completed a hydrologic and water-quality study of Fowler Lake in southeastern Wisconsin during calendar year 1984. Data on temperature, pH, specific conductance, and concentrations of dissolved oxygen, total phosphorus, dissolved orthophosphate phosphorus, and various nitrogen species were collected from January through November 1984. The water-quality data indicate that Fowler Lake can be classified as a mildly fertile lake with excellent water clarity as indicated by Secchi depth readings generally greater than 12 feet. Although phosphorus concentrations are generally less than 0.01 milligram per liter, the lake does produce dense stands of macrophytes during the open-water period. The lake is thermally stratified during the summer months, resulting in oxygen depletion in the deepest parts of the lake.

Water-quality characteristics of Michigan's inland lakes, 2001-10

Science.gov (United States)

Fuller, L.M.; Taricska, C.K.

2012-01-01

The U.S. Geological Survey and the Michigan Department of Environmental Quality (MDEQ) jointly monitored for selected water-quality constituents and properties of inland lakes during 2001–10 as part of Michigan's Lake Water-Quality Assessment program. During 2001–10, 866 lake basins from 729 inland lakes greater than 25 acres were monitored for baseline water-quality conditions and trophic status. This report summarizes the water-quality characteristics and trophic conditions of the monitored lakes throughout the State; the data include vertical-profile measurements, nutrient measurements at three discrete depths, Secchi-disk transparency (SDT) measurements, and chlorophyll a measurements for the spring and summer, with major ions and other chemical indicators measured during the spring at mid-depth and color during the summer from near-surface samples. In about 75 percent of inland lake deep basins (index stations), trophic characteristics were associated with oligotrophic or mesotrophic conditions; 5 percent or less were categorized as hypereutrophic, and 80 percent of hypereutrophic lakes had a maximum depth of 30 feet or less. Comparison of spring and summer measurements shows that water clarity based on SDT measurements were clearer in the spring than in the summer for 63 percent of lakes. For near-surface measurements made in spring, 97 percent of lakes can be considered phosphorus limited and less than half a percent nitrogen limited; for summer measurements, 96 percent of lakes can be considered phosphorus limited and less than half a percent nitrogen limited. Spatial patterns of major ions, alkalinity, and hardness measured in the spring at mid-depth all showed lower values in the Upper Peninsula of Michigan and a southward increase toward the southern areas of the Lower Peninsula, though the location of increase varied by constituent. A spatial analysis of the data based on U.S. Environmental Protection Agency Level III Ecoregions separated potassium

Water levels and groundwater and surface-water exchanges in lakes of the northeast Twin Cities Metropolitan Area, Minnesota, 2002 through 2015

Science.gov (United States)

Jones, Perry M.; Trost, Jared J.; Erickson, Melinda L.

2016-10-19

OverviewThis study assessed lake-water levels and regional and local groundwater and surface-water exchanges near northeast Twin Cities Metropolitan Area lakes applying three approaches: statistical analysis, field study, and groundwater-flow modeling.  Statistical analyses of lake levels were completed to assess the effect of physical setting and climate on lake-level fluctuations of selected lakes. A field study of groundwater and surface-water interactions in selected lakes was completed to (1) estimate potential percentages of surface-water contributions to well water across the northeast Twin Cities Metropolitan Area, (2) estimate general ages for waters extracted from the wells, and (3) assess groundwater inflow to lakes and lake-water outflow to aquifers downgradient from White Bear Lake.  Groundwater flow was simulated using a steady-state, groundwater-flow model to assess regional groundwater and surface-water exchanges and the effects of groundwater withdrawals, climate, and other factors on water levels of northeast Twin Cities Metropolitan Area lakes.

Multi-temporal image analysis of historical aerial photographs and recent satellite imagery reveals evolution of water body surface area and polygonal terrain morphology in Kobuk Valley National Park, Alaska

International Nuclear Information System (INIS)

Necsoiu, Marius; Dinwiddie, Cynthia L; Walter, Gary R; Stothoff, Stuart A; Larsen, Amy

2013-01-01

Multi-temporal image analysis of very-high-resolution historical aerial and recent satellite imagery of the Ahnewetut Wetlands in Kobuk Valley National Park, Alaska, revealed the nature of thaw lake and polygonal terrain evolution over a 54-year period of record comprising two 27-year intervals (1951–1978, 1978–2005). Using active-contouring-based change detection, high-precision orthorectification and co-registration and the normalized difference index, surface area expansion and contraction of 22 shallow water bodies, ranging in size from 0.09 to 179 ha, and the transition of ice-wedge polygons from a low- to a high-centered morphology were quantified. Total surface area decreased by only 0.4% during the first time interval, but decreased by 5.5% during the second time interval. Twelve water bodies (ten lakes and two ponds) were relatively stable with net surface area decreases of ≤10%, including four lakes that gained area during both time intervals, whereas ten water bodies (five lakes and five ponds) had surface area losses in excess of 10%, including two ponds that drained completely. Polygonal terrain remained relatively stable during the first time interval, but transformation of polygons from low- to high-centered was significant during the second time interval. (letter)

An 11 000-year-long record of fire and vegetation history at Beaver Lake, Oregon, central Willamette Valley

Science.gov (United States)

Walsh, Megan K.; Pearl, Christopher A.; Whitlock, Cathy; Bartlein, Patrick J.; Worona, Marc A.

2010-01-01

High-resolution macroscopic charcoal and pollen analysis were used to reconstruct an 11??000-year-long record of fire and vegetation history from Beaver Lake, Oregon, the first complete Holocene paleoecological record from the floor of the Willamette Valley. In the early Holocene (ca 11??000-7500 calendar years before present [cal??yr??BP]), warmer, drier summers than at present led to the establishment of xeric woodland of Quercus, Corylus, and Pseudotsuga near the site. Disturbances (i.e., floods, fires) were common at this time and as a result Alnus rubra grew nearby. High fire frequency occurred in the early Holocene from ca 11??200-9300??cal??yr??BP. Riparian forest and wet prairie developed in the middle Holocene (ca 7500??cal??yr??BP), likely the result of a decrease in the frequency of flooding and a shift to effectively cooler, wetter conditions than before. The vegetation at Beaver Lake remained generally unchanged into the late Holocene (from 4000??cal??yr??BP to present), with the exception of land clearance associated with Euro-American settlement of the valley (ca 160??cal??yr BP). Middle-to-late Holocene increases in fire frequency, coupled with abrupt shifts in fire-episode magnitude and charcoal composition, likely indicate the influence anthropogenic burning near the site. The paleoecological record from Beaver Lake, and in particular the general increase in fire frequency over the last 8500??years, differs significantly from other low-elevation sites in the Pacific Northwest, which suggests that local controls (e.g., shifts in vegetation structure, intensification of human land-use), rather than regional climatic controls, more strongly influenced its environmental history. ?? 2010 Elsevier Ltd.

Using satellite images to monitor glacial-lake outburst floods: Lago Cachet Dos drainage, Chile

Science.gov (United States)

Friesen, Beverly A.; Cole, Christopher J.; Nimick, David A.; Wilson, Earl M.; Fahey, Mark J.; McGrath, Daniel J.; Leidich, Jonathan

2015-01-01

The U.S. Geological Survey (USGS) is monitoring and analyzing glacial-lake outburst floods (GLOFs) in the Colonia valley in the Patagonia region of southern Chile. A GLOF is a type of flood that occurs when water impounded by a glacier or a glacial moraine is released catastrophically. In the Colonia valley, GLOFs originating from Lago Cachet Dos, which is dammed by the Colonia Glacier, have recurred periodically since 2008. The water discharged during these GLOFs flows under or through the Colonia Glacier, into Lago Colonia and then the Río Colonia, and finally into the Río Baker—Chile's largest river in terms of volume of water.

Fluctuations of Lake Orta water levels: preliminary analyses

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Helmi Saidi

2016-04-01

Full Text Available While the effects of past industrial pollution on the chemistry and biology of Lake Orta have been well documented, annual and seasonal fluctuations of lake levels have not yet been studied. Considering their potential impacts on both the ecosystem and on human safety, fluctuations in lake levels are an important aspect of limnological research. In the enormous catchment of Lake Maggiore, there are many rivers and lakes, and the amount of annual precipitation is both high and concentrated in spring and autumn. This has produced major flood events, most recently in November 2014. Flood events are also frequent on Lake Orta, occurring roughly triennially since 1917. The 1926, 1951, 1976 and 2014 floods were severe, with lake levels raised from 2.30 m to 3.46 m above the hydrometric zero. The most important event occurred in 1976, with a maximum level equal to 292.31 m asl and a return period of 147 years. In 2014 the lake level reached 291.89 m asl and its return period was 54 years. In this study, we defined trends and temporal fluctuations in Lake Orta water levels from 1917 to 2014, focusing on extremes. We report both annual maximum and seasonal variations of the lake water levels over this period. Both Mann-Kendall trend tests and simple linear regression were utilized to detect monotonic trends in annual and seasonal extremes, and logistic regression was used to detect trends in the number of flood events. Lake level decreased during winter and summer seasons, and a small but statistically non-significant positive trend was found in the number of flood events over the period. We provide estimations of return period for lake levels, a metric which could be used in planning lake flood protection measures.

Groundwater and Thaw Legacy of a Large Paleolake in Taylor Valley, East Antarctica as Evidenced by Airborne Electromagnetic and Sedimentological Techniques

Science.gov (United States)

Doran, P. T.; Myers, K. F.; Foley, N.; Tulaczyk, S. M.; Dugan, H. A.; Auken, E.; Mikucki, J.; Virginia, R. A.

2017-12-01

The McMurdo Dry Valleys (MDVs) in east Antarctica contain a number of perennial ice-covered lakes fed by ephemeral meltwater streams. Lake Fryxell in Taylor Valley, is roughly 5.5 km long and approximately 22 m deep. Paleodeltas and paleoshorelines throughout Fryxell Basin provide evidence of significant lake level change occurring since the Last Glacial Maximum (LGM). During the LGM, grounded ice in the Ross Sea extended into the eastern portion of Taylor Valley, creating a large ice dammed paleolake. Glacial Lake Washburn (GLW) was roughly 300 m higher than modern day Lake Fryxell and its formation and existence has been debated. In this study, we use Geographical Information System and remote sensing techniques paired with regional resistivity data to provide new insight into the paleohydrology of the region. The existence of GLW is supported by new findings of a deep groundwater system beneath Lake Fryxell, which is interpreted as the degrading thaw bulb of GLW. Airborne resistivity data collected by SkyTEM, a time-domain airborne electromagnetic sensor system was used to map groundwater systems in the lake basin. Subsurface characteristics can be inferred from the relationship of resistivity to temperature, salinity, porosity, and degree of saturation. A large low resistivity region indicative of liquid water extends hundreds of meters away from the modern lake extent which is consistent with the presence of a degrading thaw bulb from GLW. As lake level in Fryxell Basin fell to modern levels, the saturated sediment beneath the lake began to freeze as it became exposed to low atmospheric temperatures. We hypothesize that this process is ongoing and will continue until equilibrium is reached between the geothermal gradient and atmospheric temperatures. Though liquid groundwater systems were previously thought to be minimal or nonexistent in the MDVs, regional resistivity data now show that extensive groundwater reservoirs exist beneath these lakes. In addition

Water and nutrient budgets for Vancouver Lake, Vancouver, Washington, October 2010-October 2012

Science.gov (United States)

Sheibley, Rich W.; Foreman, James R.; Marshall, Cameron A.; Welch, Wendy B.

2014-01-01

Vancouver Lake, a large shallow lake in Clark County, near Vancouver, Washington, has been undergoing water-quality problems for decades. Recently, the biggest concern for the lake are the almost annual harmful cyanobacteria blooms that cause the lake to close for recreation for several weeks each summer. Despite decades of interest in improving the water quality of the lake, fundamental information on the timing and amount of water and nutrients entering and exiting the lake is lacking. In 2010, the U.S. Geological Survey conducted a 2-year field study to quantify water flows and nutrient loads in order to develop water and nutrient budgets for the lake. This report presents monthly and annual water and nutrient budgets from October 2010–October 2012 to identify major sources and sinks of nutrients. Lake River, a tidally influenced tributary to the lake, flows into and out of the lake almost daily and composed the greatest proportion of both the water and nutrient budgets for the lake, often at orders of magnitude greater than any other source. From the water budget, we identified precipitation, evaporation and groundwater inflow as minor components of the lake hydrologic cycle, each contributing 1 percent or less to the total water budget. Nutrient budgets were compiled monthly and annually for total nitrogen, total phosphorus, and orthophosphate; and, nitrogen loads were generally an order of magnitude greater than phosphorus loads across all sources. For total nitrogen, flow from Lake River at Felida, Washington, made up 88 percent of all inputs into the lake. For total phosphorus and orthophosphate, Lake River at Felida flowing into the lake was 91 and 76 percent of total inputs, respectively. Nutrient loads from precipitation and groundwater inflow were 1 percent or less of the total budgets. Nutrient inputs from Burnt Bridge Creek and Flushing Channel composed 12 percent of the total nitrogen budget, 8 percent of the total phosphorus budget, and 21 percent

Hydrogeology and water quality of the West Valley Creek Basin, Chester County, Pennsylvania

Science.gov (United States)

Senior, Lisa A.; Sloto, Ronald A.; Reif, Andrew G.

1997-01-01

The West Valley Creek Basin drains 20.9 square miles in the Piedmont Physiographic Province of southeastern Pennsylvania and is partly underlain by carbonate rocks that are highly productive aquifers. The basin is undergoing rapid urbanization that includes changes in land use and increases in demand for public water supply and wastewater disposal. Ground water is the sole source of supply in the basin.West Valley Creek flows southwest in a 1.5-mile-wide valley that is underlain by folded and faulted carbonate rocks and trends east-northeast, parallel to regional geologic structures. The valley is flanked by hills underlain by quartzite and gneiss to the north and by phyllite and schist to the south. Surface water and ground water flow from the hills toward the center of the valley. Ground water in the valley flows west-southwest parallel to the course of the stream. Seepage investigations identified losing reaches in the headwaters area where streams are underlain by carbonate rocks and gaining reaches downstream. Tributaries contribute about 75 percent of streamflow. The ground-water and surface-water divides do not coincide in the carbonate valley. The ground-water divide is about 0.5 miles west of the surface-water divide at the eastern edge of the carbonate valley. Underflow to the east is about 1.1 inches per year. Quarry dewatering operations at the western edge of the valley may act partly as an artificial basin boundary, preventing underflow to the west. Water budgets for 1990, a year of normal precipitation (45.8 inches), and 1991, a year of sub-normal precipitation (41.5 inches), were calculated. Streamflow was 14.61 inches in 1990 and 12.08 inches in 1991. Evapotranspiration was estimated to range from 50 to 60 percent of precipitation. Base flow was about 62 percent of streamflow in both years. Exportation by sewer systems was about 3 inches from the basin and, at times, equaled base flow during the dry autumn of 1991. Recharge was estimated to be 18

Paleoecology of a Northern Michigan Lake and the relationship among climate, vegetation, and Great Lakes water levels

Science.gov (United States)

Booth, R.K.; Jackson, S.T.; Thompson, T.A.

2002-01-01

We reconstructed Holocene water-level and vegetation dynamics based on pollen and plant macrofossils from a coastal lake in Upper Michigan. Our primary objective was to test the hypothesis that major fluctuations in Great Lakes water levels resulted in part from climatic changes. We also used our data to provide temporal constraints to the mid-Holocene dry period in Upper Michigan. From 9600 to 8600 cal yr B.P. a shallow, lacustrine environment characterized the Mud Lake basin. A Sphagnum-dominated wetland occupied the basin during the mid-Holocene dry period (???8600 to 6600 cal yr B.P.). The basin flooded at 6600 cal yr B.P. as a result of rising water levels associated with the onset of the Nipissing I phase of ancestral Lake Superior. This flooding event occured contemporaneously with a well-documented regional expansion of Tsuga. Betula pollen increased during the Nipissing II phase (4500 cal yr B.P.). Macrofossil evidence from Mud Lake suggests that Betula alleghaniensis expansion was primarily responsible for the rising Betula pollen percentages. Major regional and local vegetational changes were associated with all the major Holocene highstands of the western Great Lakes (Nipissing I, Nipissing II, and Algoma). Traditional interpretations of Great Lakes water-level history should be revised to include a major role of climate. ?? 2002 University of Washington.

46 CFR 11.430 - Endorsements for the Great Lakes and inland waters.

Science.gov (United States)

2010-10-01

... 46 Shipping 1 2010-10-01 2010-10-01 false Endorsements for the Great Lakes and inland waters. 11... Endorsements for the Great Lakes and inland waters. Any license or MMC endorsement issued for service on the Great Lakes and inland waters is valid on all of the inland waters of the United States as defined in...

Valley formation by groundwater seepage, pressurized groundwater outbursts and crater-lake overflow in flume experiments with implications for Mars

NARCIS (Netherlands)

Marra, Wouter A.; Braat, Lisanne; Baar, Anne W.; Kleinhans, Maarten G.

2014-01-01

Remains of fluvial valleys on Mars reveal the former presence of water on the surface. However, the source of water and the hydrological setting is not always clear, especially in types of valleys that are rare on Earth and where we have limited knowledge of the processes involved. We investigated

Key Lake mine water spill: further clean-up not required

International Nuclear Information System (INIS)

Potvin, R.

1984-02-01

The Atomic Energy Control Board (AECB) has concluded that no additional remedial measures are warranted with regard to the mine water spill which occurred in early January at the Key Lake Mining Corporation facility in northern Saskatchewan, and has advised the company to reconsider its proposal for clean-up of the adjoining Gerald Lake basin. On January 5, an estimated 87 million litres of mine water was accidentally released to the environment when a water storage reservoir at the mine site overflowed. The spilled water flowed into the adjoining Gerald Lake catchment area where it has remained adequately contained

Assessment of Climate Change Impacts on Agricultural Water Demands and Crop Yields in California's Central Valley

Science.gov (United States)

Tansey, M. K.; Flores-Lopez, F.; Young, C. A.; Huntington, J. L.

2012-12-01

Long term planning for the management of California's water resources requires assessment of the effects of future climate changes on both water supply and demand. Considerable progress has been made on the evaluation of the effects of future climate changes on water supplies but less information is available with regard to water demands. Uncertainty in future climate projections increases the difficulty of assessing climate impacts and evaluating long range adaptation strategies. Compounding the uncertainty in the future climate projections is the fact that most readily available downscaled climate projections lack sufficient meteorological information to compute evapotranspiration (ET) by the widely accepted ASCE Penman-Monteith (PM) method. This study addresses potential changes in future Central Valley water demands and crop yields by examining the effects of climate change on soil evaporation, plant transpiration, growth and yield for major types of crops grown in the Central Valley of California. Five representative climate scenarios based on 112 bias corrected spatially downscaled CMIP 3 GCM climate simulations were developed using the hybrid delta ensemble method to span a wide range future climate uncertainty. Analysis of historical California Irrigation Management Information System meteorological data was combined with several meteorological estimation methods to compute future solar radiation, wind speed and dew point temperatures corresponding to the GCM projected temperatures and precipitation. Future atmospheric CO2 concentrations corresponding to the 5 representative climate projections were developed based on weighting IPCC SRES emissions scenarios. The Land, Atmosphere, and Water Simulator (LAWS) model was used to compute ET and yield changes in the early, middle and late 21st century for 24 representative agricultural crops grown in the Sacramento, San Joaquin and Tulare Lake basins. Study results indicate that changes in ET and yield vary

Water Balance of the Eğirdir Lake and the Influence of Budget Components, Isparta,Turkey

Directory of Open Access Journals (Sweden)

Ayşen DAVRAZ

2014-09-01

Full Text Available Water budget of lakes must be determined regarding to their sustainable usage as for all water resources. One of the major problems in the management of lakes is the estimation of water budget components. The lack of regularly measured data is the biggest problem in calculation of hydrological balance of a lake. A lake water budget is computed by measuring or estimating all of the lake’s water gains and losses and measuring the corresponding changes in the lake volume over the same time period. Eğirdir Lake is one of the most important freshwater lakes in Turkey and is the most important surface water resources in the region due to different usages. Recharge of the Eğirdir Lake is supplied from especially precipitation, surface and subsurface water inflow. The discharge components of the lake are evaporation and water intake for irrigation, drinking and energy purposes. The difference between recharge and discharge of the lake was calculated as 7.78 hm3 for 1970-2010 period. According to rainfall, evaporation and the lake water level relations, rainfall is dominantly effective on the lake water level such as direct recharge to the lake and indirect recharge with groundwater flow

The hydrogeology of the Tully Valley, Onondaga County, New York: an overview of research, 1992-2012

Science.gov (United States)

Kappel, William M.

2014-01-01

Onondaga Creek begins approximately 15 miles south of Syracuse, New York, and flows north through the Onondaga Indian Nation, then through Syracuse, and finally into Onondaga Lake in central New York. Tully Valley is in the upper part of the Onondaga Creek watershed between U.S. Route 20 and the Valley Heads end moraine near Tully, N.Y. Tully Valley has a history of several unusual hydrogeologic phenomena that affected past land use and the water quality of Onondaga Creek; the phenomena are still present and continue to affect the area today (2014). These phenomena include mud volcanoes or mudboils, landslides, and land-surface subsidence; all are considered to be naturally occurring but may also have been influenced by human activity. The U.S. Geological Survey (USGS), in cooperation with the U.S. Environmental Protection Agency and the Onondaga Lake Partnership, began a study of the Tully Valley mudboils beginning in October 1991 in hopes of understanding (1) what drives mudboil activity in order to remediate mudboil influence on the water quality of Onondaga Creek, and (2) land-surface subsidence issues that have caused a road bridge to collapse, a major pipeline to be rerouted, and threatened nearby homes. Two years into this study, the 1993 Tully Valley landslide occurred just over 1 mile northwest of the mudboils. This earth slump-mud flow was the largest landslide in New York in more than 70 years (Fickies, 1993); this event provided additional insight into the geology and hydrology of the valley. As the study of the Tully Valley mudboils progressed, other unusual hydrogeologic phenomena were found within the Tully Valley and provided the opportunity to perform short-term, small-scale studies, some of which became graduate student theses—Burgmeier (1998), Curran (1999), Morales-Muniz (2000), Baldauf (2003), Epp (2005), Hackett, (2007), Tamulonis (2010), and Sinclair (2013). The unusual geology and hydrology of the Tully Valley, having been investigated for

Evaluating lake stratification and temporal trends by using near-continuous water-quality data from automated profiling systems for water years 2005-09, Lake Mead, Arizona and Nevada

Science.gov (United States)

Veley, Ronald J.; Moran, Michael J.

2012-01-01

The U.S. Geological Survey, in cooperation with the National Park Service and Southern Nevada Water Authority, collected near-continuous depth-dependent water-quality data at Lake Mead, Arizona and Nevada, as part of a multi-agency monitoring network maintained to provide resource managers with basic data and to gain a better understanding of the hydrodynamics of the lake. Water-quality data-collection stations on Lake Mead were located in shallow water (less than 20 meters) at Las Vegas Bay (Site 3) and Overton Arm, and in deep water (greater than 20 meters) near Sentinel Island and at Virgin and Temple Basins. At each station, near-continual depth-dependent water-quality data were collected from October 2004 through September 2009. The data were collected by using automatic profiling systems equipped with multiparameter water-quality sondes. The sondes had sensors for temperature, specific conductance, dissolved oxygen, pH, turbidity, and depth. Data were collected every 6 hours at 2-meter depth intervals (for shallow-water stations) or 5-meter depth intervals (for deep-water stations) beginning at 1 meter below water surface. Data were analyzed to determine water-quality conditions related to stratification of the lake and temporal trends in water-quality parameters. Three water-quality parameters were the main focus of these analyses: temperature, specific conductance, and dissolved oxygen. Statistical temporal-trend analyses were performed for a single depth at shallow-water stations [Las Vegas Bay (Site 3) and Overton Arm] and for thermally-stratified lake layers at deep-water stations (Sentinel Island and Virgin Basin). The limited period of data collection at the Temple Basin station prevented the application of statistical trend analysis. During the summer months, thermal stratification was not observed at shallow-water stations, nor were major maxima or minima observed for specific-conductance or dissolved-oxygen profiles. A clearly-defined thermocline

Development of Turbulent Diffusion Transfer Algorithms to Estimate Lake Tahoe Water Budget

Science.gov (United States)

Sahoo, G. B.; Schladow, S. G.; Reuter, J. E.

2012-12-01

The evaporative loss is a dominant component in the Lake Tahoe hydrologic budget because watershed area (813km2) is very small compared to the lake surface area (501 km2). The 5.5 m high dam built at the lake's only outlet, the Truckee River at Tahoe City can increase the lake's capacity by approximately 0.9185 km3. The lake serves as a flood protection for downstream areas and source of water supply for downstream cities, irrigation, hydropower, and instream environmental requirements. When the lake water level falls below the natural rim, cessation of flows from the lake cause problems for water supply, irrigation, and fishing. Therefore, it is important to develop algorithms to correctly estimate the lake hydrologic budget. We developed a turbulent diffusion transfer model and coupled to the dynamic lake model (DLM-WQ). We generated the stream flows and pollutants loadings of the streams using the US Environmental Protection Agency (USEPA) supported watershed model, Loading Simulation Program in C++ (LSPC). The bulk transfer coefficients were calibrated using correlation coefficient (R2) as the objective function. Sensitivity analysis was conducted for the meteorological inputs and model parameters. The DLM-WQ estimated lake water level and water temperatures were in agreement to those of measured records with R2 equal to 0.96 and 0.99, respectively for the period 1994 to 2008. The estimated average evaporation from the lake, stream inflow, precipitation over the lake, groundwater fluxes, and outflow from the lake during 1994 to 2008 were found to be 32.0%, 25.0%, 19.0%, 0.3%, and 11.7%, respectively.

Effects of recharge, Upper Floridan aquifer heads, and time scale on simulated ground-water exchange with Lake Starr, a seepage lake in central Florida

Science.gov (United States)

Swancar, Amy; Lee, Terrie Mackin

2003-01-01

Lake Starr and other lakes in the mantled karst terrain of Florida's Central Lake District are surrounded by a conductive surficial aquifer system that receives highly variable recharge from rainfall. In addition, downward leakage from these lakes varies as heads in the underlying Upper Floridan aquifer change seasonally and with pumpage. A saturated three-dimensional finite-difference ground-water flow model was used to simulate the effects of recharge, Upper Floridan aquifer heads, and model time scale on ground-water exchange with Lake Starr. The lake was simulated as an active part of the model using high hydraulic conductivity cells. Simulated ground-water flow was compared to net ground-water flow estimated from a rigorously derived water budget for the 2-year period August 1996-July 1998. Calibrating saturated ground-water flow models with monthly stress periods to a monthly lake water budget will result in underpredicting gross inflow to, and leakage from, ridge lakes in Florida. Underprediction of ground-water inflow occurs because recharge stresses and ground-water flow responses during rainy periods are averaged over too long a time period using monthly stress periods. When inflow is underestimated during calibration, leakage also is underestimated because inflow and leakage are correlated if lake stage is maintained over the long term. Underpredicted leakage reduces the implied effect of ground-water withdrawals from the Upper Floridan aquifer on the lake. Calibrating the weekly simulation required accounting for transient responses in the water table near the lake that generated the greater range of net ground-water flow values seen in the weekly water budget. Calibrating to the weekly lake water budget also required increasing the value of annual recharge in the nearshore region well above the initial estimate of 35 percent of the rainfall, and increasing the hydraulic conductivity of the deposits around and beneath the lake. To simulate the total

Ciliate diversity, community structure, and novel taxa in lakes of the McMurdo Dry Valleys, Antarctica.

Science.gov (United States)

Xu, Yuan; Vick-Majors, Trista; Morgan-Kiss, Rachael; Priscu, John C; Amaral-Zettler, Linda

2014-10-01

We report an in-depth survey of next-generation DNA sequencing of ciliate diversity and community structure in two permanently ice-covered McMurdo Dry Valley lakes during the austral summer and autumn (November 2007 and March 2008). We tested hypotheses on the relationship between species richness and environmental conditions including environmental extremes, nutrient status, and day length. On the basis of the unique environment that exists in these high-latitude lakes, we expected that novel taxa would be present. Alpha diversity analyses showed that extreme conditions-that is, high salinity, low oxygen, and extreme changes in day length-did not impact ciliate richness; however, ciliate richness was 30% higher in samples with higher dissolved organic matter. Beta diversity analyses revealed that ciliate communities clustered by dissolved oxygen, depth, and salinity, but not by season (i.e., day length). The permutational analysis of variance test indicated that depth, dissolved oxygen, and salinity had significant influences on the ciliate community for the abundance matrices of resampled data, while lake and season were not significant. This result suggests that the vertical trends in dissolved oxygen concentration and salinity may play a critical role in structuring ciliate communities. A PCR-based strategy capitalizing on divergent eukaryotic V9 hypervariable region ribosomal RNA gene targets unveiled two new genera in these lakes. A novel taxon belonging to an unknown class most closely related to Cryptocaryon irritans was also inferred from separate gene phylogenies. © 2014 Marine Biological Laboratory.

Baseline risk assessment of ground water contamination at the Monument Valley Uranium Mill Tailings Site, Cane Valley, Arizona. Revision 1

Energy Technology Data Exchange (ETDEWEB)

1994-08-01

This baseline risk assessment evaluates potential impact to public health or the environment from ground water contamination at the former uranium mill processing site in Cane Valley near Monument Valley, Arizona. The US Department of Energy (DOE) Uranium Mill Tailings Remedial Action (UMTRA) Project has relocated and stabilized this site`s tailings and other contaminated material in a disposal cell at Mexican Hat, Utah. The second phase of the UMTRA Project is to evaluate ground water contamination. This risk assessment is the first document specific to this site for the Ground Water Project that evaluates potential health and environmental risks. It will help determine the approach required to address contaminated ground water at the site.

Baseline risk assessment of ground water contamination at the Monument Valley Uranium Mill Tailings Site, Cane Valley, Arizona. Revision 1

International Nuclear Information System (INIS)

1994-08-01

This baseline risk assessment evaluates potential impact to public health or the environment from ground water contamination at the former uranium mill processing site in Cane Valley near Monument Valley, Arizona. The US Department of Energy (DOE) Uranium Mill Tailings Remedial Action (UMTRA) Project has relocated and stabilized this site's tailings and other contaminated material in a disposal cell at Mexican Hat, Utah. The second phase of the UMTRA Project is to evaluate ground water contamination. This risk assessment is the first document specific to this site for the Ground Water Project that evaluates potential health and environmental risks. It will help determine the approach required to address contaminated ground water at the site

Water ecological carrying capacity of urban lakes in the context of rapid urbanization: A case study of East Lake in Wuhan

Science.gov (United States)

Ding, Lei; Chen, Kun-lun; Cheng, Sheng-gao; Wang, Xu

With the excessive development of social economy, water scarcity and water environment deterioration become a common phenomenon in metropolis. As a crucial component of urban water environment system, urban lake is mainly influenced by social economic system and tourism system. In this paper, a framework for quantitatively evaluating development sustainability of urban lake was established by a multi-objective model that represented water ecological carrying capacity (WECC). And nine key indicators including population, irrigation area, tourist quantity, the average number of hotel daily reception, TP, TN, CODMn, BOD5 were chosen from urban social-economy system and natural resilience aspects, with their index weight was determined by using the Structure Entropy Weight method. Then, we took Wuhan East Lake, the largest urban lake in China as a case study, and selected five time sections including 2002, 2004, 2007, 2009 and 2012 to synthetically evaluate and comparatively analyze the dynamic change of WECC. The results showed that: firstly, the water ecological carrying capacity values of the East Lake in five time sections were 1.17, 1.07, 1.64, 1.53 and 2.01 respectively, which all exceeded 1 and increased fluctuation. The rapid growth of population and GDP lead to sharply increasing demand for water quantity. However, a large amount of the domestic sewage and industrial waste led by economic development increases pressure on ecological environment of urban lakes. Secondly, the carrying capacity of the East Lake for tourist activities was still low. The value in 2012 was only 0.22, keeping at a slowly increasing phase, which indicates that the East Lake has large opportunity and space for developing the water resource carrying capacity and could make further efforts to attract tourists. Moreover, the WECC of the East Lake was mainly affected by rapid social and economic development and water environment damage caused by organic pollutants. From the view of urban

76 FR 58840 - Central Valley Project Improvement Act; Refuge Water Management Plans

Science.gov (United States)

2011-09-22

... DEPARTMENT OF THE INTERIOR Bureau of Reclamation Central Valley Project Improvement Act; Refuge Water Management Plans AGENCY: Bureau of Reclamation, Interior. ACTION: Notice of availability. SUMMARY: To meet the requirements of the Central Valley Project Improvement Act of 1992 (CVPIA) and subsequent...

LakeSST: Lake Skin Surface Temperature in French inland water bodies for 1999-2016 from Landsat archives

Science.gov (United States)

Prats, Jordi; Reynaud, Nathalie; Rebière, Delphine; Peroux, Tiphaine; Tormos, Thierry; Danis, Pierre-Alain

2018-04-01

The spatial and temporal coverage of the Landsat satellite imagery make it an ideal resource for the monitoring of water temperature over large territories at a moderate spatial and temporal scale at a low cost. We used Landsat 5 and Landsat 7 archive images to create the Lake Skin Surface Temperature (LakeSST) data set, which contains skin water surface temperature data for 442 French water bodies (natural lakes, reservoirs, ponds, gravel pit lakes and quarry lakes) for the period 1999-2016. We assessed the quality of the satellite temperature measurements by comparing them to in situ measurements and taking into account the cool skin and warm layer effects. To estimate these effects and to investigate the theoretical differences between the freshwater and seawater cases, we adapted the COARE 3.0 algorithm to the freshwater environment. We also estimated the warm layer effect using in situ data. At the reservoir of Bimont, the estimated cool skin effect was about -0.3 and -0.6 °C most of time, while the warm layer effect at 0.55 m was negligible on average, but could occasionally attain several degrees, and a cool layer was often observed in the night. The overall RMSE of the satellite-derived temperature measurements was about 1.2 °C, similar to other applications of satellite images to estimate freshwater surface temperatures. The LakeSST data can be used for studies on the temporal evolution of lake water temperature and for geographical studies of temperature patterns. The LakeSST data are available at https://doi.org/10.5281/zenodo.1193745" target="_blank">https://doi.org/10.5281/zenodo.1193745.

The importance of lake-specific characteristics for water quality across the continental United States.

Science.gov (United States)

Read, Emily K; Patil, Vijay P; Oliver, Samantha K; Hetherington, Amy L; Brentrup, Jennifer A; Zwart, Jacob A; Winters, Kirsten M; Corman, Jessica R; Nodine, Emily R; Woolway, R Iestyn; Dugan, Hilary A; Jaimes, Aline; Santoso, Arianto B; Hong, Grace S; Winslow, Luke A; Hanson, Paul C; Weathers, Kathleen C

2015-06-01

Lake water quality is affected by local and regional drivers, including lake physical characteristics, hydrology, landscape position, land cover, land use, geology, and climate. Here, we demonstrate the utility of hypothesis testing within the landscape limnology framework using a random forest algorithm on a national-scale, spatially explicit data set, the United States Environmental Protection Agency's 2007 National Lakes Assessment. For 1026 lakes, we tested the relative importance of water quality drivers across spatial scales, the importance of hydrologic connectivity in mediating water quality drivers, and how the importance of both spatial scale and connectivity differ across response variables for five important in-lake water quality metrics (total phosphorus, total nitrogen, dissolved organic carbon, turbidity, and conductivity). By modeling the effect of water quality predictors at different spatial scales, we found that lake-specific characteristics (e.g., depth, sediment area-to-volume ratio) were important for explaining water quality (54-60% variance explained), and that regionalization schemes were much less effective than lake specific metrics (28-39% variance explained). Basin-scale land use and land cover explained between 45-62% of variance, and forest cover and agricultural land uses were among the most important basin-scale predictors. Water quality drivers did not operate independently; in some cases, hydrologic connectivity (the presence of upstream surface water features) mediated the effect of regional-scale drivers. For example, for water quality in lakes with upstream lakes, regional classification schemes were much less effective predictors than lake-specific variables, in contrast to lakes with no upstream lakes or with no surface inflows. At the scale of the continental United States, conductivity was explained by drivers operating at larger spatial scales than for other water quality responses. The current regulatory practice of using

Recent changes in the deep-water fish populations of Lake Michigan

Science.gov (United States)

Moffett, James W.

1957-01-01

The deep-water fish fauna of Lake Michigan consisted of lake trout (Salvelinus namaycush), burbot (Lota lota maculosa), seven species of chubs or deep-water ciscoes (Leucichthys spp.), and the deep-water sculpin (Myoxocephalus quadricornis). Other species occupied the deep-water zone but were not typically part of the fauna.

The Socio-hydrology of Bangalore's Lake System and implications for Urban Water Security

Science.gov (United States)

Srinivasan, V.; Roy, S.

2017-12-01

Bengaluru city has experienced unprecedented growth in recent decades. If the city is to sustain growth and claim its position as a "global" high-tech city, it must be able to secure sufficient water supply and also create a healthy livable environment. With the city's many lakes vanishing due to rapid urbanisation, depletion of groundwater as a result of overuse in the peri-urban areas, and lack of proper underground drainage system and sewage treatment plants, Bangalore is now grappling with issues of imminent water crisis, inequitable access to water supply, and public health hazards. In this context, the restoration of Bangalore's lakes has been promoted as a panacea for its flooding, water stress, and wastewater problems. It has been argued that lakes can store storm water and recycled wastewater and avoid the need for potentially destructive, expensive schemes that may destroy biodiversity rich aquatic ecosystems and forests. Bangalore's lakes are linked by the drainage channels to form a cascade; overflow from each lake flows to the next lake downstream. Yet, most efforts have tended to view the lakes in isolation. This study of the hydrology of Bangalore's lake system in its entirety simulates the lake system as a whole. The study explores approaches to management and theor impact on urban water security.

75 FR 45579 - Water Quality Standards for the State of Florida's Lakes and Flowing Waters; Supplemental Notice...

Science.gov (United States)

2010-08-03

... Water Quality Standards for the State of Florida's Lakes and Flowing Waters; Supplemental Notice of Data...), proposing numeric nutrient water quality criteria to protect aquatic life in lakes and flowing waters within... will consider the comments received before finalizing the proposed rule, ``Water Quality Standards for...

Status and understanding of groundwater quality in the Bear Valley and Lake Arrowhead Watershed Study Unit, 2010: California GAMA Priority Basin Project

Science.gov (United States)

Mathany, Timothy; Burton, Carmen

2017-06-20

Groundwater quality in the 112-square-mile Bear Valley and Lake Arrowhead Watershed (BEAR) study unit was investigated as part of the Priority Basin Project (PBP) of the Groundwater Ambient Monitoring and Assessment (GAMA) Program. The study unit comprises two study areas (Bear Valley and Lake Arrowhead Watershed) in southern California in San Bernardino County. The GAMA-PBP is conducted by the California State Water Resources Control Board (SWRCB) in cooperation with the U.S. Geological Survey (USGS) and the Lawrence Livermore National Laboratory.The GAMA BEAR study was designed to provide a spatially balanced, robust assessment of the quality of untreated (raw) groundwater from the primary aquifer systems in the two study areas of the BEAR study unit. The assessment is based on water-quality collected by the USGS from 38 sites (27 grid and 11 understanding) during 2010 and on water-quality data from the SWRCB-Division of Drinking Water (DDW) database. The primary aquifer system is defined by springs and the perforation intervals of wells listed in the SWRCB-DDW water-quality database for the BEAR study unit.This study included two types of assessments: (1) a status assessment, which characterized the status of the quality of the groundwater resource as of 2010 by using data from samples analyzed for volatile organic compounds, pesticides, and naturally present inorganic constituents, such as major ions and trace elements, and (2) an understanding assessment, which evaluated the natural and human factors potentially affecting the groundwater quality. The assessments were intended to characterize the quality of groundwater resources in the primary aquifer system of the BEAR study unit, not the treated drinking water delivered to consumers. Bear Valley study area and the Lake Arrowhead Watershed study area were also compared statistically on the basis of water-quality results and factors potentially affecting the groundwater quality.Relative concentrations (RCs

Water Quality Conditions in Upper Klamath and Agency Lakes, Oregon, 2006

Science.gov (United States)

Lindenberg, Mary K.; Hoilman, Gene; Wood, Tamara M.

2008-01-01

The U.S. Geological Survey Upper Klamath Lake water quality monitoring program gathered information from multiparameter continuous water quality monitors, physical water samples, dissolved oxygen production and consumption experiments, and meteorological stations during the June-October 2006 field season. The 2006 study area included Agency Lake and all of Upper Klamath Lake. Seasonal patterns in water quality were similar to those observed in 2005, the first year of the monitoring program, and were closely related to bloom dynamics of the cyanobacterium (blue-green alga) Aphanizomenon flos-aquae (AFA) in the two lakes. High dissolved oxygen and pH conditions in both lakes before the bloom declined in July, which coincided with seasonal high temperatures and resulted in seasonal lows in dissolved oxygen and decreased pH. Dissolved oxygen and pH in Upper Klamath and Agency Lakes increased again after the bloom recovered. Seasonal low dissolved oxygen and decreased pH coincided with seasonal highs in ammonia and orthophosphate concentrations. Seasonal maximum daily average temperatures were higher and minimum dissolved oxygen concentrations were lower in 2006 than in 2005. Conditions potentially harmful to fish were influenced by seasonal patterns in bloom dynamics and bathymetry. Potentially harmful low dissolved oxygen and high un-ionized ammonia concentrations occurred mostly at the deepest sites in the Upper Klamath Lake during late July, coincident with a bloom decline. Potentially harmful pH conditions occurred mostly at sites outside the deepest parts of the lake in July and September, coincident with a heavy bloom. Instances of possible gas bubble formation, inferred from dissolved oxygen data, were estimated to occur frequently in shallow areas of Upper Klamath and Agency Lakes simultaneously with potentially harmful pH conditions. Comparison of the data from monitors in nearshore areas and monitors near the surface of the water column in the open waters of

Water Balance and Level Change of Lake Babati, Tanzania: Sensitivity to Hydroclimatic Forcings

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René P. Mbanguka

2016-12-01

Full Text Available We develop and present a novel integrated water balance model that accounts for lake water—groundwater interactions, and apply it to the semi-closed freshwater Lake Babati system, Northern Tanzania, East Africa. The model was calibrated and used to evaluate the lake level sensitivity to changes in key hydro-climatic variables such as temperature, precipitation, humidity and cloudiness. The lake response to the Coupled Model Intercomparison Project, Phase 5 (CMIP5 output on possible future climate outcomes was evaluated, an essential basis in understanding future water security and flooding risk in the region. Results show high lake level sensitivity to cloudiness. Increased focus on cloud fraction measurement and interpretation could likely improve projections of lake levels and surface water availability. Modelled divergent results on the future (21st century development of Lake Babati can be explained by the precipitation output variability of CMIP5 models being comparable to the precipitation change needed to drive the water balance model from lake dry-out to overflow; this condition is likely shared with many other East African lake systems. The developed methodology could be useful in investigations on change-driving processes in complex climate—drainage basin—lake systems, which are needed to support sustainable water resource planning in data scarce tropical Africa.

Chemical Evolution of Groundwater Near a Sinkhole Lake, Northern Florida: 1. Flow Patterns, Age of Groundwater, and Influence of Lake Water Leakage

Science.gov (United States)

Katz, Brian G.; Lee, Terrie M.; Plummer, L. Niel; Busenberg, Eurybiades

1995-06-01

Leakage from sinkhole lakes significantly influences recharge to the Upper Floridan aquifer in poorly confined sediments in northern Florida. Environmental isotopes (oxygen 18, deuterium, and tritium), chlorofluorocarbons (CFCs: CFC-11, CCl3F; CFC-12, CCl2F2; and CFC-113, C2Cl3F3), and solute tracers were used to investigate groundwater flow patterns near Lake Barco, a seepage lake in a mantled karst setting in northern Florida. Stable isotope data indicated that the groundwater downgradient from the lake contained 11-67% lake water leakage, with a limit of detection of lake water in groundwater of 4.3%. The mixing fractions of lake water leakage, which passed through organic-rich sediments in the lake bottom, were directly proportional to the observed methane concentrations and increased with depth in the groundwater flow system. In aerobic groundwater upgradient from Lake Barco, CFC-modeled recharge dates ranged from 1987 near the water table to the mid 1970s for water collected at a depth of 30 m below the water table. CFC-modeled recharge dates (based on CFC-12) for anaerobic groundwater downgradient from the lake ranged from the late 1950s to the mid 1970s and were consistent with tritium data. CFC-modeled recharge dates based on CFC-11 indicated preferential microbial degradation in anoxic waters. Vertical hydraulic conductivities, calculated using CFC-12 modeled recharge dates and Darcy's law, were 0.17, 0.033, and 0.019 m/d for the surficial aquifer, intermediate confining unit, and lake sediments, respectively. These conductivities agreed closely with those used in the calibration of a three-dimensional groundwater flow model for transient and steady state flow conditions.

Concentrations of arsenic in brackish lake water : Application of tristimulus colorimetric determination

OpenAIRE

Rahman, Md. Mustafizur; Seike, Yasushi; Okumura, Minoru

2006-01-01

The evaluation of a simple and rapid tristimulus colorimetric method for the determination of arsenic in brackish waters and its application to brackish water samples taken from brackish Lake Nakaumi are described. The determinations of arsenic in brackish water samples were made satisfactorily independent of sample salinity. By applying this method to lake water samples, the distributions and behaviors of arsenic in the lake and their controlling factors were clarified, such as seasonal vari...

Water clarity of the Upper Great Lakes: tracking changes between 1998-2012

Science.gov (United States)

Yousef, F.; Shuchman, R. A.; Sayers, M.; Fahnenstiel, G.; Henareh Khalyani, A.

2016-12-01

Water clarity trends in three upper Great Lakes, Lakes Superior, Michigan, and Huron, were assessed via satellite imagery from 1998 to 2012. Water attenuation coefficients (Kd490) from SeaWiFS and Aqua MODIS satellites compared favorably with in situ measurements. Significant temporal and spatial trends and differences in Kd490 were noted within all three of the lakes. Lake-wide average Kd490 for Lake Superior did not exhibited any changes between 1998 and 2012. Annual Kd490 values for Lake Huron, however, showed a significant negative trend during the study period using both SeaWiFS and MODIS datasets. Similarly, annual Kd490 values of Lake Michigan declined between 1998 and 2010. Additionally, Kd490 trend for depths >90m in northern Lake Michigan reversed (increased) after 2007. Photic depth increased significantly in both Lake Michigan (≃5m), and Lake Huron (≃10m) when comparing annual Kd490 for pre- (1998-2001) and post-mussel (2006-2010). At seasonal level, significant decreases in Kd490 in lakes Michigan and Huron were mainly noted for the spring/fall/winter mixing periods. After current changes in water clarity, lake-wide photic depths in lakes Michigan and Huron superseded Lake Superior; thus, making Lake Superior no longer the clearest Great Lake. Combination of several factors (filtering activities of quagga mussels [Dreissena bugensis rostriformis], phosphorus abatement, climate change, etc.) are likely responsible for these large changes.

Physical and Chemical Characteristics of Lake Edku Water, Egypt

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M.A. OKBAH

2002-12-01

Full Text Available The objective of this work is to evaluate the quality of Lake Edku water. Regional and seasonal variations of some physico-chemical parameters (nutrient salts, total nitrogen, total phosphorous and silicate, in addition to pH, total alkalinity, chlorosity, dissolved oxygen, biological oxygen demand and oxidizable organic matter that were determined during the period from January to December 2000. Important variations have occurred in the investigated area as a result of human activity and the discharge of wastewater to the lake. The relatively low pH values reflect the decreased productivity of the Lake as a result of the polluted water discharged into the lake. Total alkalinity varied between 2.25 ± 0.35 to 8.38 ± 0.9 meq/l. In comparison with previous decades chlorosity content (586-1562 mg/l showed the general decreasing trend. Dissolved oxygen varied (2.37 ± 0.72 - 4.47 ± 0.94 mg/l. The ratios of BOD/ OOM values indicate that the lake water has a biodegradable nature. There was a noticeable variation in ammonia levels; a lower ammonia content was recorded in summer and spring. Nitrite and nitrate concentrations in Lake Edku water showed values ranging from 3.7±1.4 to 7.8±1.9 ΜM and from 15.2±2.9 to 45.9±11.8 ΜM, respectively. The total nitrogen of the lake exhibited higher levels (53.1±12.2 – 164.2±30.7 ΜM. The ratio of NH4/TIN (0.09-0.45 seems to be highly representative of the microbial nitrification rate as well as of the varying agricultural inflows. It is interesting to note that increasing values of reactive phosphate (11.6±1.8 – 14.7±2.5 ΜM were determined in autumn and winter respectively. The higher concentrations of reactive silicate were directly proportional to drainage water discharged into the Lake. It is clear from the mean ratio of N/P (2.4-8.8 nitrogen is the limiting factor. The lower values of N/P ratio could be related to an allochthonous condition.

The reproductive biology of an open-water spawning Lake Malawi ...

African Journals Online (AJOL)

The reproductive biology of an open-water spawning Lake Malawi cichlid, Copadichromis chrysonotus. Lance W. Smith. Abstract. Copadichromis chrysonotus is a zooplanktivorous cichlid member of the diverse fish community inhabiting Lake Malawi's rocky, littoral habitat. Like most Lake Malawi cichlids, this species' ...

Long Valley Caldera Lake and reincision of Owens River Gorge

Science.gov (United States)

Hildreth, Wes; Fierstein, Judy

2016-12-16

Owens River Gorge, today rimmed exclusively in 767-ka Bishop Tuff, was first cut during the Neogene through a ridge of Triassic granodiorite to a depth as great as its present-day floor and was then filled to its rim by a small basaltic shield at 3.3 Ma. The gorge-filling basalt, 200 m thick, blocked a 5-km-long reach of the upper gorge, diverting the Owens River southward around the shield into Rock Creek where another 200-m-deep gorge was cut through the same basement ridge. Much later, during Marine Isotope Stage (MIS) 22 (~900–866 ka), a piedmont glacier buried the diversion and deposited a thick sheet of Sherwin Till atop the basalt on both sides of the original gorge, showing that the basalt-filled reach had not, by then, been reexcavated. At 767 ka, eruption of the Bishop Tuff blanketed the landscape with welded ignimbrite, deeply covering the till, basalt, and granodiorite and completely filling all additional reaches of both Rock Creek canyon and Owens River Gorge. The ignimbrite rests directly on the basalt and till along the walls of Owens Gorge, but nowhere was it inset against either, showing that the basalt-blocked reach had still not been reexcavated. Subsidence of Long Valley Caldera at 767 ka produced a steep-walled depression at least 700 m deeper than the precaldera floor of Owens Gorge, which was beheaded at the caldera’s southeast rim. Caldera collapse reoriented proximal drainages that had formerly joined east-flowing Owens River, abruptly reversing flow westward into the caldera. It took 600,000 years of sedimentation in the 26-km-long, usually shallow, caldera lake to fill the deep basin and raise lake level to its threshold for overflow. Not until then did reestablishment of Owens River Gorge begin, by incision of the gorge-filling ignimbrite.

Treating cooling pond water for Wabamun Lake level mitigation project in Alberta

International Nuclear Information System (INIS)

Anon

2004-01-01

Dealing with the challenge of recharging Wabamun Lake by treating nearby cooling pond water, fed by the North Saskatchewan River, and returning it to the lake, is discussed. To deal with the problem, TransAlta Utilities constructed a treatment plant in 1997 next to the 2,029 MW Sundance power plant to mitigate the effect the power plant's ongoing and historical effect on the lake's water level. The objective of the treatment plant is to treat cooling pond water and return it to the lake to raise water levels there, which have been significantly reduced over the last 25 years mostly by power plant intake, but also by lack of rainfall, surface runoff, and natural evaporation. At the Treatment Facility the water to be treated is first chlorinated to kill zooplankton, algae and bacteria, followed by adjusting the pH using sulfuric acid. Alum coagulant is used to destabilize colour, particles and colloids. The next step is feeding the water to the Actiflo clarifiers which use microsand to provide increased surface area for floc attachment, and to act as ballast. Clarified water from the Actiflo system is then fed to to the Dusenflo filters to remove the largest particles of suspended solids, and through a finer sand media to remove the remaining turbidity, colour and bacteria. Thiosulfate is used in the ozonation system to inactivate any remaining bacteria and zooplankton in the filtered water, before discharging it to the lake. The cooling towers, which are part of the system, ensure that the treated water returned to the lake is kept at a constant temperature, varying no more than three degrees C from the lake water temperature. 3 figs

Water-quality and bottom-material characteristics of Cross Lake, Caddo Parish, Louisiana, 1997-99

Science.gov (United States)

McGee, Benton D.

2004-01-01

Cross Lake is a shallow, monomictic lake that was formed in 1926 by the impoundment of Cross Bayou. The lake is the primary drinking-water supply for the City of Shreveport, Louisiana. In recent years, the lakeshore has become increasinginly urbanized. In addition, the land use of the watershed contributing runoff to Cross Lake has changed. Changes in land use and urbanization could affect the water chemistry and biology of the Lake. Water-quality data were collected at 10 sites on Cross Lake from February 1997 to February 1999. Water-column and bottom-material samples were collected. The water-column samples were collected at least four times per year. These samples included physical and chemical-related properties such as water temperature, dissolved oxygen, pH, and specific conductance; selected major inorganic ions; nutrients; minor elements; organic chemical constituents; and bacteria. Suspended-sediment samples were collected seven times during the sampling period. The bottom-material samples, which were collected once during the sampling period, were analyzed for selected minor elements and inorganic carbon. Aside from the nutrient-enriched condition of Cross Lake, the overall water-quality of Cross Lake is good. No primary Federal or State water-quality criteria were exceeded by any of the water-quality constituents analyzed for this report. Concentrations of major inorganic constituents, except iron and manganese, were low. Water from the lake is a sodium-bicarbonate type and is soft. Minor elements and organic compounds were present in low concentrations, many below detection limits. Nitrogen and phosphorus were the nutrients occurring in the highest concentrations. Nutrients were evenly distributed across the lake with no particular water-quality site indicating consistently higher or lower nutrient concentrations. No water samples analyzed for nitrate exceeded the U.S. Environmental Protection Agency's Maximum Contaminant Level of 10 milligrams per

Evaluation of Water Security in Kathmandu Valley before and after Water Transfer from another Basin

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Bhesh Raj Thapa

2018-02-01

Full Text Available Kathmandu Upatyaka Khanepani Limited (KUKL has planned to harness water from outside the valley from Melamchi as an inter-basin project to supply water inside the ring road (core valley area of the Kathmandu Valley (KV. The project, called the “Melamchi Water Supply Project (MWSP”, is expected to have its first phase completed by the end of September 2018 and its second phase completed by the end of 2023 to supply 170 MLD (million liters a day through the first phase and an additional 340 MLD through the second phase. The area has recently faced a severe water deficit and KUKL’s existing infrastructure has had a limited capability, supplying only 19% of the water that is demanded in its service areas during the dry season and 31% during the wet season. In this context, this study aims to assess the temporal trends and spatial distribution of household water security index (WSI, defined as a ratio of supply to demand for domestic water use for basic human water requirements (50 L per capita per day (lpcd and economic growth (135 lpcd as demand in pre- and post-MWSP scenarios. For this purpose, data on water demand and supply with infrastructure were used to map the spatial distribution of WSI and per capita water supply using ArcMap. Results show a severe water insecurity condition in the year 2017 in all KUKL service areas (SAs, which is likely to improve after completion of the MWSP. It is likely that recent distribution network and strategies may lead to inequality in water distribution within the SAs. This can possibly be addressed by expanding existing distribution networks and redistributing potable water, which can serve an additional 1.21 million people in the area. Service providers may have to develop strategies to strengthen a set of measures including improving water supply infrastructures, optimizing water loss, harnessing additional water from hills, and managing water within and outside the KUKL SAs in the long run to cover

Simulation of hydrodynamics, water quality, and lake sturgeon habitat volumes in Lake St. Croix, Wisconsin and Minnesota, 2013

Science.gov (United States)

Smith, Erik A.; Kiesling, Richard L.; Ziegeweid, Jeffrey R.; Elliott, Sarah M.; Magdalene, Suzanne

2018-01-05

Lake St. Croix is a naturally impounded, riverine lake that makes up the last 40 kilometers of the St. Croix River. Substantial land-use changes during the past 150 years, including increased agriculture and urban development, have reduced Lake St. Croix water-quality and increased nutrient loads delivered to Lake St. Croix. A recent (2012–13) total maximum daily load phosphorus-reduction plan set the goal to reduce total phosphorus loads to Lake St. Croix by 20 percent by 2020 and reduce Lake St. Croix algal bloom frequencies. The U.S. Geological Survey, in cooperation with the National Park Service, developed a two-dimensional, carbon-based, laterally averaged, hydrodynamic and water-quality model, CE–QUAL–W2, that addresses the interaction between nutrient cycling, primary production, and trophic dynamics to predict responses in the distribution of water temperature, oxygen, and chlorophyll a. Distribution is evaluated in the context of habitat for lake sturgeon, including a combination of temperature and dissolved oxygen conditions termed oxy-thermal habitat.The Lake St. Croix CE–QUAL–W2 model successfully reproduced temperature and dissolved oxygen in the lake longitudinally (from upstream to downstream), vertically, and temporally over the seasons. The simulated water temperature profiles closely matched the measured water temperature profiles throughout the year, including the prediction of thermocline transition depths (often within 1 meter), the absolute temperature of the thermocline transitions (often within 1.0 degree Celsius), and profiles without a strong thermocline transition. Simulated dissolved oxygen profiles matched the trajectories of the measured dissolved oxygen concentrations at multiple depths over time, and the simulated concentrations matched the depth and slope of the measured concentrations.Additionally, trends in the measured water-quality data were captured by the model simulation, gaining some potential insights into the

Radioactivity levels in surface water of lakes around Izmir / Turkey

International Nuclear Information System (INIS)

Doyurum, S.; Turkozu, D. A.; Aslani, M. A. A.; Aytas, S.; Eral, M.; Kaygun, A. K.

2006-01-01

Radioactivity presents in surface continental waters is mainly due to the presence of radioactive elements in the earth's crust, other artificial radionuclides have appeared due to such human activities as nuclear power plants, nuclear weapons testing and manufacture and use of radioactive sources It is well known that natural radionuclides can be effective as tracers for the different processes controlling the distribution of elements among dissolved and particulate phases in aquatic systems. The detection of high radionuclide concentrations was proposed as a public health problem in several areas and consequently studies into the risks of radionuclides were started in the 2000s. Especially, these radioactive substances in groundwater are an unwanted and involuntary risk factor from natural sources, not artificial sources. These radioactive substances include uranium, radon found in uranium series, and other radioactive substances such as radium and gross alpha. Uranium present in rock, soil, and natural materials, and is found in small quantities in air, water, and food that people always contact. In this project, lake water samples were collected from three lakes around Izmir-Turkey. In surface lake water samples, pH, mV and conductivity values were measured and alkaline content was determined titrimetrically. The uranium concentrations in the lake water samples were measured using uranium analyzer. The radioactivity concentrations related to gross radium isotopes, gross-? and gross-? activities in the surface lake water were determined. The correlation among some parameters for water samples and concentrations of uranium, activity concentration of gross radium isotopes, gross alpha and gross beta radioactivity are also discussed

Challenge to the model of lake charr evolution: Shallow- and deep-water morphs exist within a small postglacial lake

Science.gov (United States)

Chavarie, Louise; Muir, Andrew M.; Zimmerman, Mara S.; Baillie, Shauna M.; Hansen, Michael J.; Nate, Nancy A.; Yule, Daniel L.; Middel, Trevor; Bentzen, Paul; Krueger, Charles C.

2016-01-01

All examples of lake charr (Salvelinus namaycush) diversity occur within the largest, deepest lakes of North America (i.e. > 2000 km2). We report here Rush Lake (1.3 km2) as the first example of a small lake with two lake charr morphs (lean and huronicus). Morphology, diet, life history, and genetics were examined to demonstrate the existence of morphs and determine the potential influence of evolutionary processes that led to their formation or maintenance. Results showed that the huronicus morph, caught in deep-water, had a deeper body, smaller head and jaws, higher eye position, greater buoyancy, and deeper peduncle than the shallow-water lean morph. Huronicus grew slower to a smaller adult size, and had an older mean age than the lean morph. Genetic comparisons showed low genetic divergence between morphs, indicating incomplete reproductive isolation. Phenotypic plasticity and differences in habitat use between deep and shallow waters associated with variation in foraging opportunities seems to have been sufficient to maintain the two morphs, demonstrating their important roles in resource polymorphism. Rush Lake expands previous explanations for lake charr intraspecific diversity, from large to small lakes and from reproductive isolation to the presence of gene flow associated with strong ecological drivers.

Simulation and assessment of groundwater flow and groundwater and surface-water exchanges in lakes of the northeast Twin Cities Metropolitan Area, Minnesota, 2003 through 2013: Chapter B of Water levels and groundwater and surface-water exchanges in lakes of the northeast Twin Cities Metropolitan Area, Minnesota, 2002 through 2015

Science.gov (United States)

Jones, Perry M.; Roth, Jason L.; Trost, Jared J.; Christenson, Catherine A.; Diekoff, Aliesha L.; Erickson, Melinda L.

2017-09-05

Water levels during 2003 through 2013 were less than mean water levels for the period 1925–2013 for several lakes in the northeast Twin Cities Metropolitan Area in Minnesota. Previous periods of low lake-water levels generally were correlated with periods with less than mean precipitation. Increases in groundwater withdrawals and land-use changes have brought into question whether or not recent (2003–13) lake-water-level declines are solely caused by decreases in precipitation. A thorough understanding of groundwater and surface-water exchanges was needed to assess the effect of water-management decisions on lake-water levels. To address this need, the U.S. Geological Survey, in cooperation with the Metropolitan Council and the Minnesota Department of Health, developed and calibrated a three-dimensional, steady-state groundwater-flow model representing 2003–13 mean hydrologic conditions to assess groundwater and lake-water exchanges, and the effects of groundwater withdrawals and precipitation on water levels of 96 lakes in the northeast Twin Cities Metropolitan Area.Lake-water budgets for the calibrated groundwater-flow model indicated that groundwater is flowing into lakes in the northeast Twin Cities Metropolitan Area and lakes are providing water to underlying aquifers. Lake-water outflow to the simulated groundwater system was a major outflow component for Big Marine Lake, Lake Elmo, Snail Lake, and White Bear Lake, accounting for 45 to 64 percent of the total outflows from the lakes. Evaporation and transpiration from the lake surface ranged from 19 to 52 percent of the total outflow from the four lakes. Groundwater withdrawals and precipitation were varied from the 2003‒13 mean values used in the calibrated model (30-percent changes in groundwater withdrawals and 5-percent changes in precipitation) for hypothetical scenarios to assess the effects of groundwater withdrawals and precipitation on water budgets and levels in Big Marine Lake, Snail Lake

Understanding the groundwater dynamics in the Southern Rift Valley Lakes Basin (Ethiopia). Multivariate statistical analysis method, oxygen (δ 18O) and deuterium (δ 2H)

International Nuclear Information System (INIS)

Girum Admasu Nadew; Zebene Lakew Tefera

2013-01-01

Multivariate statistical analysis is very important to classify waters of different hydrochemical groups. Statistical techniques, such as cluster analysis, can provide a powerful tool for analyzing water chemistry data. This method is used to test water quality data and determine if samples can be grouped into distinct populations that may be significant in the geologic context, as well as from a statistical point of view. Multivariate statistical analysis method is applied to the geochemical data in combination with δ 18 O and δ 2 H isotopes with the objective to understand the dynamics of groundwater using hierarchical clustering and isotope analyses. The geochemical and isotope data of the central and southern rift valley lakes have been collected and analyzed from different works. Isotope analysis shows that most springs and boreholes are recharged by July and August rainfalls. The different hydrochemical groups that resulted from the multivariate analysis are described and correlated with the geology of the area and whether it has any interaction with a system or not. (author)

Molecular Determinants of Dissolved Organic Matter Reactivity in Lake Water

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Alina Mostovaya

2017-12-01

Full Text Available Lakes in the boreal region have been recognized as the biogeochemical hotspots, yet many questions regarding the regulators of organic matter processing in these systems remain open. Molecular composition can be an important determinant of dissolved organic matter (DOM fate in freshwater systems, but many aspects of this relationship remain unclear due to the complexity of DOM and its interactions in the natural environment. Here, we combine ultrahigh resolution mass spectrometry (FT-ICR-MS with kinetic modeling of decay of >1,300 individual DOM molecular formulae identified by mass spectrometry, to evaluate the role of specific molecular characteristics in decomposition of lake water DOM. Our data is derived from a 4 months microbial decomposition experiment, carried out on water from three Swedish lakes, with the set-up including natural lake water, as well as the lake water pretreated with UV light. The relative decay rate of every molecular formula was estimated by fitting a single exponential model to the change in FT-ICR-MS signal intensities over decomposition time. We found a continuous range of exponential decay coefficients (kexp within different groups of compounds and show that for highly unsaturated and phenolic compounds the distribution of kexp was shifted toward the lowest values. Contrary to this general trend, plant-derived polyphenols and polycondensed aromatics were on average more reactive than compounds with an intermediate aromaticity. The decay rate of aromatic compounds increased with increasing nominal oxidation state of carbon, and molecular mass in some cases showed an inverse relationship with kexp in the UV-manipulated treatment. Further, we observe an increase in formulae-specific kexp as a result of the UV pretreatment. General trends in reactivity identified among major compound groups emphasize the importance of the intrinsic controllers of lake water DOM decay. However, we additionally indicate that each

Trends and variability of water quality in Lake Tana, Ethiopia using MODIS-Aqua

Science.gov (United States)

DeLuca, N. M.; Zaitchik, B. F.; Monger, B. C.

2017-12-01

Determining long-term water quality trends and variability in remote inland lakes has been challenging due to a lack of continuous in situ measurements. Utilizing ocean color remote sensing techniques for these lakes is difficult due to their sizes, shapes, and optically complex waters. Lake Tana is the largest body of water in Ethiopia, and is located in the country's northwestern highlands. The lake is quite shallow, averaging at about 8 meters depth, and is characteristically turbid due to nearby land degradation and high soil erosion rates. Lake Tana is an important source of accessible water for the rapidly growing population of Ethiopia and serves as the headwaters for the Blue Nile. Therefore, understanding water quality trends and seasonal variation over the past decade is essential to better preparing for future water needs. Here we use MODIS-Aqua data spanning years 2002-2016 to investigate these trends and variability in Lake Tana, where in situ measurements are limited. Daily water quality products were first processed using SeaDAS and then aggregated by month and year for analyses. Frequent cloud cover in the June, July, and August (JJA) rainy season due to monsoon and zonal dynamics presents an obstacle for obtaining mean lake values during these months. We also performed analyses on targeted regions of Lake Tana to determine whether some of the major tributaries and their corresponding watersheds have more influence on observed trends than others.

[Similarities and differences in absorption characteristics and composition of CDOM between Taihu Lake and Chaohu Lake].

Science.gov (United States)

Shi, Kun; Li, Yun-mei; Wang, Qiao; Yang, Yu; Jin, Xin; Wang, Yan-fei; Zhang, Hong; Yin, Bin

2010-05-01

Field experiments are conducted separately in Taihu Lake and Chaohu Lake on Apr. and Jun. 2009. The changes in absorption spectra of chromophoric dissolved organic matter (CDOM) characteristics are analyzed using spectral differential analysis technology. According the spectral differential characteristic of absorption coefficient; absorption coefficient from 240 to 450 nm is divided into different stages, and the value of spectral slope S is calculated in each stage. In Stage A, S value of CDOM in Taihu Lake and Chaohu Lake are 0.0166-0.0102 nm(-1) [average (0.0132 +/- 0.0017) nm(-1)], 0.029-0.017 nm(-1) [average (0.0214 +/- 0.0024) nm(-1)]. In Stage B, S values are 0.0187-0.0148 nm(-1) [average (0.0169 +/- 0.001) nm(-1)], 0.0179-0.0055 nm(-1) [average (0.0148 +/- 0.002) nm(-1)]. In Stage C, S values are 0.0208-0.0164 nm(-1) [average (0.0186 +/- 0.0009) nm(-1)], 0.0253-0.0161 nm(-1) [average (0.0197 +/- 0.002) nm(-1)]. The results can be concluded as: (1) Absorption coefficient of water in Taihu Lake, and its contribution to absorption of each component is less than that of water in Chaohu Lake, however the standardized absorption coefficient is larger than that in Chaohu Lake. (2) Both in Taihu Lake and Chaohu Lake, derivative spectra of CDOM absorption coefficient reached valley at 260nm, then rise to top at 290 nm, CDOM absorption coefficient can be delivered into three stages. (3) Generally speaking, content of CDOM in Taihu Lake is less than in Chaohu Lake. (4) pectrum slope (S value) of CDOM is related to composition of CDOM, when content of humic acid in CDOM gets higher, S value of Stage B is the most sensitive value, then is the S value of Stage C. Oppositely, S value of Stage B gets the most sensitive value, then is the S value of Stage A; the least sensitive value is in Stage B.

Compilation of geologic, hydrologic, and ground-water flow modeling information for the Spokane Valley-Rathdrum Prairie aquifer, Spokane County, Washington, and Bonner and Kootenai Counties, Idaho

Science.gov (United States)

Kahle, Sue C.; Caldwell, Rodney R.; Bartolino, James R.

2005-01-01

The U.S. Geological Survey, in cooperation with the Idaho Department of Water Resources and Washington Department of Ecology compiled and described geologic, hydrologic, and ground-water flow modeling information about the Spokane Valley-Rathdrum Prairie (SVRP) aquifer in northern Idaho and northeastern Washington. Descriptions of the hydrogeologic framework, water-budget components, ground- and surface-water interactions, computer flow models, and further data needs are provided. The SVRP aquifer, which covers about 370 square miles including the Rathdrum Prairie, Idaho and the Spokane valley and Hillyard Trough, Washington, was designated a Sole Source Aquifer by the U.S. Environmental Protection Agency in 1978. Continued growth, water management issues, and potential effects on water availability and water quality in the aquifer and in the Spokane and Little Spokane Rivers have illustrated the need to better understand and manage the region's water resources. The SVRP aquifer is composed of sand, gravel, cobbles, and boulders primarily deposited by a series of catastrophic glacial outburst floods from ancient Glacial Lake Missoula. The material deposited in this high-energy environment is coarser-grained than is typical for most basin-fill deposits, resulting in an unusually productive aquifer with well yields as high as 40,000 gallons per minute. In most places, the aquifer is bounded laterally by bedrock composed of granite, metasedimentary rocks, or basalt. The lower boundary of the aquifer is largely unknown except along the margins or in shallower parts of the aquifer where wells have penetrated its entire thickness and reached bedrock or silt and clay deposits. Based on surface geophysics, the thickness of the aquifer is about 500 ft near the Washington-Idaho state line, but more than 600 feet within the Rathdrum Prairie and more than 700 feet in the Hillyard trough based on drilling records. Depth to water in the aquifer is greatest in the northern

77 FR 33240 - Central Valley Project Improvement Act, Water Management Plans

Science.gov (United States)

2012-06-05

... Project water conservation best management practices that shall ``develop criteria for evaluating the... DEPARTMENT OF THE INTERIOR Bureau of Reclamation Central Valley Project Improvement Act, Water Management Plans AGENCY: Bureau of Reclamation, Interior. ACTION: Notice of availability. SUMMARY: The...

Decadal-scale changes in dissolved-solids concentrations in groundwater used for public supply, Salt Lake Valley, Utah

Science.gov (United States)

Thiros, Susan A.; Spangler, Larry

2010-01-01

Basin-fill aquifers are a major source of good-quality water for public supply in many areas of the southwestern United States and have undergone increasing development as populations have grown over time. During 2005, the basin-fill aquifer in Salt Lake Valley, Utah, provided approximately 75,000 acre-feet, or about 29 percent of the total amount of water used by a population of 967,000. Groundwater in the unconsolidated basin-fill deposits that make up the aquifer occurs under unconfined and confined conditions. Water in the shallow unconfined part of the groundwater system is susceptible to near-surface contamination and generally is not used as a source of drinking water. Groundwater for public supply is withdrawn from the deeper unconfined and confined parts of the system, termed the principal aquifer, because yields generally are greater and water quality is better (including lower dissolved-solids concentrations) than in the shallower parts of the system. Much of the water in the principal aquifer is derived from recharge in the adjacent Wasatch Range (mountain-block recharge). In many areas, the principal aquifer is separated from the overlying shallow aquifer by confining layers of less permeable, fine-grained sediment that inhibit the downward movement of water and any potential contaminants from the surface. Nonetheless, under certain hydrologic conditions, human-related activities can increase dissolved-solids concentrations in the principal aquifer and result in groundwater becoming unsuitable for consumption without treatment or mixing with water having lower dissolved-solids concentrations. Dissolved-solids concentrations in areas of the principal aquifer used for public supply typically are less than 500 milligrams per liter (mg/L), the U.S. Environmental Protection Agency (EPA) secondary (nonenforceable) drinking-water standard. However, substantial increases in dissolved-solids concentrations in the principal aquifer have been documented in some

Estimating the effects of land-use and catchment characteristics on lake water quality: Irish lakes 2004-2009

OpenAIRE

Curtis, John; Morgenroth, Edgar

2013-01-01

This paper attributes the variation in water quality across Irish lakes to a range of contributory factors such as human population, septic tanks, urban waste water treatment, phosphorous excreted by livestock, as well as catchment soil and geology. Both linear and non-linear quadratic models were estimated in the analysis, which attempts to account for point and non-point sources of pollution affecting water quality in 216 lake catchments. The models show a clear link between activities with...

Methane oxidation in anoxic lake waters

Science.gov (United States)

Su, Guangyi; Zopfi, Jakob; Niemann, Helge; Lehmann, Moritz

2017-04-01

Freshwater habitats such as lakes are important sources of methante (CH4), however, most studies in lacustrine environments so far provided evidence for aerobic methane oxidation only, and little is known about the importance of anaerobic oxidation of CH4 (AOM) in anoxic lake waters. In marine environments, sulfate reduction coupled to AOM by archaea has been recognized as important sinks of CH4. More recently, the discorvery of anaerobic methane oxidizing denitrifying bacteria represents a novel and possible alternative AOM pathway, involving reactive nitrogen species (e.g., nitrate and nitrite) as electron acceptors in the absence of oxygen. We investigate anaerobic methane oxidation in the water column of two hydrochemically contrasting sites in Lake Lugano, Switzerland. The South Basin displays seasonal stratification, the development of a benthic nepheloid layer and anoxia during summer and fall. The North Basin is permanently stratified with anoxic conditions below 115m water depth. Both Basins accumulate seasonally (South Basin) or permanently (North Basin) large amounts of CH4 in the water column below the chemocline, providing ideal conditions for methanotrophic microorganisms. Previous work revealed a high potential for aerobic methane oxidation within the anoxic water column, but no evidence for true AOM. Here, we show depth distribution data of dissolved CH4, methane oxidation rates and nutrients at both sites. In addition, we performed high resolution phylogenetic analyses of microbial community structures and conducted radio-label incubation experiments with concentrated biomass from anoxic waters and potential alternative electron acceptor additions (nitrate, nitrite and sulfate). First results from the unamended experiments revealed maximum activity of methane oxidation below the redoxcline in both basins. While the incubation experiments neither provided clear evidence for NOx- nor sulfate-dependent AOM, the phylogenetic analysis revealed the

Microplastics in surface waters of Dongting Lake and Hong Lake, China.

Science.gov (United States)

Wang, Wenfeng; Yuan, Wenke; Chen, Yuling; Wang, Jun

2018-08-15

Microplastics pollution is an environmental issue of increasing concern. Much work has been done on the microplastics pollution in the marine environments. Although freshwaters are potential sources and transport pathways of plastic debris to the oceans, there is a lack of knowledge regarding the presence of microplastics in freshwater systems, especially in China, the world's largest producer of plastics. This study investigated the occurrence and properties of microplastics in surface waters of two important lakes in the middle reaches of the Yangtze River. The concentration ranges of microplastics in Dongting Lake and Hong Lake were 900-2800 and 1250-4650n/m 3 , respectively. Fiber was the dominant shape. Colored items occupied the majority. Particles with a size of 20% of total microplastics collected in both lakes. Most of the selected particles were identified as plastics, with polyethylene (PE) and polypropylene (PP) being the major components. This study can provide valuable reference for better understanding the microplastics pollution in inland freshwater ecosystems. Copyright © 2018 Elsevier B.V. All rights reserved.

Economic and Water Supply Effects of Ending Groundwater Overdraft in California's Central Valley

Directory of Open Access Journals (Sweden)

Timothy Nelson

2016-03-01

Full Text Available doi: http://dx.doi.org/10.15447/sfews.2016v14iss1art7Surface water and groundwater management are often tightly linked, even when linkage is not intended or expected. This link is especially common in semi-arid regions, such as California. This paper summarizes a modeling study on the effects of ending long-term overdraft in California’s Central Valley, the state’s largest aquifer system. The study focuses on economic and operational aspects, such as surface water pumping and diversions, groundwater recharge, water scarcity, and the associated operating and water scarcity costs. This analysis uses CALVIN, a hydro-economic optimization model for California’s water resource system that suggests operational changes to minimize net system costs for a given set of conditions, such as ending long-term overdraft. Based on model results, ending overdraft might induce some major statewide operational changes, including large increases to Delta exports, more intensive conjunctive-use operations with increasing artificial and in-lieu recharge, and greater water scarcity for Central Valley agriculture. The statewide costs of ending roughly 1.2 maf yr-1 of groundwater overdraft are at least $50 million per year from additional direct water shortage and additional operating costs. At its worst, the costs of ending Central Valley overdraft could be much higher, perhaps comparable to the recent economic effects of drought. Driven by recent state legislation to improve groundwater sustainability, ending groundwater overdraft has important implications statewide for water use and management, particularly in the Sacramento–San Joaquin Delta. Ending Central Valley overdraft will amplify economic pressure to increase Delta water exports rather than reduce them, tying together two of California’s largest water management problems.

Tilted lake shorelines record the onset of motion along the Hilton Creek fault adjacent to Long Valley caldera, CA, USA

Science.gov (United States)

Perkins, J. P.; Finnegan, N. J.; Cervelli, P. F.; Langbein, J. O.

2010-12-01

Prominent normal faults occur within and around Long Valley caldera, in the eastern Sierra Nevada of California. However, their relationship to both the magmatic and tectonic evolution of the caldera since the 760 ka eruption of the Bishop Tuff remains poorly understood. In particular, in the Mono-Inyo Craters north of Long Valley, extensional faulting appears to be replaced by dike intrusion where magma is available in the crust. However, it is unclear whether extensional faults in Long Valley caldera have been active since the eruption of the Bishop Tuff (when the current topography was established) or are a relatively young phenomenon owing to the cooling and crystallization of the Long Valley magma reservoir. Here we use GPS geodesy and geomorphology to investigate the evolution of the Hilton Creek fault, the primary range-front fault bounding Long Valley caldera to the southwest. Our primary goals are to determine how long the Hilton Creek fault has been active and whether slip rates have been constant over that time interval. To characterize the modern deformation field, we capitalize on recently (July, 2010) reoccupied GPS benchmarks first established in 1999-2000. These fixed-array GPS data show no discernible evidence for recent slip on the Hilton Creek fault, which further highlights the need for longer-term constraints on fault motion. To establish a fault slip history, we rely on a suite of five prominent shorelines from Pleistocene Long Valley Lake whose ages are well constrained based on field relationships to dated lavas, and that are tilted southward toward the Hilton Creek fault. A preliminary analysis of shoreline orientations using GPS surveys and a 5-m-resolution Topographic Synthetic Aperture Radar (TOPSAR) digital elevation model shows that lake shorelines tilt towards the Hilton Creek fault at roughly parallel gradients (~ 0.6%). The measured shorelines range in inferred age from 100 ka to 500 ka, which constrain recent slip on the Hilton

78 FR 63491 - Central Valley Project Improvement Act, Water Management Plans

Science.gov (United States)

2013-10-24

... Valley Project Improvement Act, Water Management Plans AGENCY: Bureau of Reclamation, Interior. ACTION: Notice of availability. SUMMARY: The following Water Management Plans are available for review: Westside... project contractors using best available cost-effective technology and best management practices.'' These...

Statistical analysis of lake levels and field study of groundwater and surface-water exchanges in the northeast Twin Cities Metropolitan Area, Minnesota, 2002 through 2015: Chapter A of Water levels and groundwater and surface-water exchanges in lakes of the northeast Twin Cities Metropolitan Area, Minnesota, 2002 through 2015

Science.gov (United States)

Jones, Perry M.; Trost, Jared J.; Diekoff, Aliesha L.; Rosenberry, Donald O.; White, Eric A.; Erickson, Melinda L.; Morel, Daniel L.; Heck, Jessica M.

2016-10-19

Water levels declined from 2003 to 2011 in many lakes in Ramsey and Washington Counties in the northeast Twin Cities Metropolitan Area, Minnesota; however, water levels in other northeast Twin Cities Metropolitan Area lakes increased during the same period. Groundwater and surface-water exchanges can be important in determining lake levels where these exchanges are an important component of the water budget of a lake. An understanding of groundwater and surface-water exchanges in the northeast Twin Cities Metropolitan Area has been limited by the lack of hydrologic data. The U.S. Geological Survey, in cooperation with the Metropolitan Council and Minnesota Department of Health, completed a field and statistical study assessing lake-water levels and regional and local groundwater and surface-water exchanges near northeast Twin Cities Metropolitan Area lakes. This report documents the analysis of collected hydrologic, water-quality, and geophysical data; and existing hydrologic and geologic data to (1) assess the effect of physical setting and climate on lake-level fluctuations of selected lakes, (2) estimate potential percentages of surface-water contributions to well water across the northeast Twin Cities Metropolitan Area, (3) estimate general ages for waters extracted from the wells, and (4) assess groundwater inflow to lakes and lake-water outflow to aquifers downgradient from White Bear Lake. Statistical analyses of lake levels during short-term (2002–10) and long-term (1925–2014) periods were completed to help understand lake-level changes across the northeast Twin Cities Metropolitan Area. Comparison of 2002–10 lake levels to several landscape and geologic characteristics explained variability in lake-level changes for 96 northeast Twin Cities Metropolitan Area lakes. Application of several statistical methods determined that (1) closed-basin lakes (without an active outlet) had larger lake-level declines than flow-through lakes with an outlet; (2

Long-term citizen-collected data reveal geographical patterns and temporal trends in lake water clarity

Science.gov (United States)

Lottig, Noah R.; Wagner, Tyler; Henry, Emily N.; Cheruvelil, Kendra Spence; Webster, Katherine E.; Downing, John A.; Stow, Craig A.

2014-01-01

We compiled a lake-water clarity database using publically available, citizen volunteer observations made between 1938 and 2012 across eight states in the Upper Midwest, USA. Our objectives were to determine (1) whether temporal trends in lake-water clarity existed across this large geographic area and (2) whether trends were related to the lake-specific characteristics of latitude, lake size, or time period the lake was monitored. Our database consisted of >140,000 individual Secchi observations from 3,251 lakes that we summarized per lake-year, resulting in 21,020 summer averages. Using Bayesian hierarchical modeling, we found approximately a 1% per year increase in water clarity (quantified as Secchi depth) for the entire population of lakes. On an individual lake basis, 7% of lakes showed increased water clarity and 4% showed decreased clarity. Trend direction and strength were related to latitude and median sample date. Lakes in the southern part of our study-region had lower average annual summer water clarity, more negative long-term trends, and greater inter-annual variability in water clarity compared to northern lakes. Increasing trends were strongest for lakes with median sample dates earlier in the period of record (1938–2012). Our ability to identify specific mechanisms for these trends is currently hampered by the lack of a large, multi-thematic database of variables that drive water clarity (e.g., climate, land use/cover). Our results demonstrate, however, that citizen science can provide the critical monitoring data needed to address environmental questions at large spatial and long temporal scales. Collaborations among citizens, research scientists, and government agencies may be important for developing the data sources and analytical tools necessary to move toward an understanding of the factors influencing macro-scale patterns such as those shown here for lake water clarity.

Microbial methane production in oxygenated water column of an oligotrophic lake

Science.gov (United States)

Grossart, Hans-Peter; Frindte, Katharina; Dziallas, Claudia; Eckert, Werner; Tang, Kam W.

2011-01-01

The prevailing paradigm in aquatic science is that microbial methanogenesis happens primarily in anoxic environments. Here, we used multiple complementary approaches to show that microbial methane production could and did occur in the well-oxygenated water column of an oligotrophic lake (Lake Stechlin, Germany). Oversaturation of methane was repeatedly recorded in the well-oxygenated upper 10 m of the water column, and the methane maxima coincided with oxygen oversaturation at 6 m. Laboratory incubations of unamended epilimnetic lake water and inoculations of photoautotrophs with a lake-enrichment culture both led to methane production even in the presence of oxygen, and the production was not affected by the addition of inorganic phosphate or methylated compounds. Methane production was also detected by in-lake incubations of lake water, and the highest production rate was 1.8–2.4 nM⋅h−1 at 6 m, which could explain 33–44% of the observed ambient methane accumulation in the same month. Temporal and spatial uncoupling between methanogenesis and methanotrophy was supported by field and laboratory measurements, which also helped explain the oversaturation of methane in the upper water column. Potentially methanogenic Archaea were detected in situ in the oxygenated, methane-rich epilimnion, and their attachment to photoautotrophs might allow for anaerobic growth and direct transfer of substrates for methane production. Specific PCR on mRNA of the methyl coenzyme M reductase A gene revealed active methanogenesis. Microbial methane production in oxygenated water represents a hitherto overlooked source of methane and can be important for carbon cycling in the aquatic environments and water to air methane flux. PMID:22089233

40 CFR Appendix B to Part 132 - Great Lakes Water Quality Initiative

Science.gov (United States)

2010-07-01

... 40 Protection of Environment 21 2010-07-01 2010-07-01 false Great Lakes Water Quality Initiative B Appendix B to Part 132 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) WATER PROGRAMS... Water Quality Initiative Methodology for Deriving Bioaccumulation Factors Great Lakes States and Tribes...

Landscape history and man-induced landscape changes in the young morainic area of the North European Plain — a case study from the Bäke Valley, Berlin

Science.gov (United States)

Böse, Margot; Brande, Arthur

2010-10-01

The Bäke creek valley is part of the young morainic area in Berlin. Its origin is related to meltwater flow and dead-ice persistence resulting in a valley with a lake-creek system. During the Late Glacial, the slopes of the valley were affected by solifluction. A Holocene brown soil developed in this material, whereas parts of the lakes were filled with limnic-telmatic sediments. The excavation site at Goerzallee revealed Bronze Age and Iron Age burial places at the upper part of the slope, as well as a fireplace further downslope, but the slope itself remained stable. Only German settlements in the 12th and 13th centuries changed the processes in the creek-lake system: the construction of water mills created a retention system with higher ground water levels in the surrounding areas. On the other hand, deforestation on the till plain and on the slope triggered erosion. Therefore, in medieval time interfingering organic sediments and sand layers were deposited in the lower part of the slope on top of the Holocene soil. The new soil which formed on top of these sediments was transformed by ploughing until the 19th century. In 1905/06 the lower part of the slope was reshaped by the construction of the Teltow Canal, following the valley of the former Bäke creek. Finally, the whole area was levelled by infill after World War II.

Assessing heat fluxes and water quality trends in subalpine lakes from EO

Science.gov (United States)

Cazzaniga, Ilaria; Giardino, Claudia; Bresciani, Mariano; Elli, Chiara; Valerio, Giulia; Pilotti, Marco

2017-04-01

Lakes play a fundamental role in providing ecosystem services such as water supplying, hydrological regulation, climate change mitigation, touristic recreation (Schallenberg et al., 2013). Preserving and improving of quality of lakes waters, which is a function of either both natural and human influences, is therefore an important action to be considered. Remote Sensing techniques are spreading as useful instrument for lakes, by integrating classical in situ limnological measurements to frequent and synoptic monitoring capabilities. Within this study, Earth Observation data are exploited for understanding the temporal changes of water quality parameters over a decade, as well as for measuring the surface energy fluxes in recent years in deep clear lakes in the European subalpine ecoregion. According to Pareth et al. (2016), subalpine lakes are showing a clear response to climate change with an increase of 0.017 °C /year of lake surface temperature, whilst the human activities contribute to produce a large impact (agriculture, recreation, industry, fishing and drinking) on these lakes. The investigation is focused on Lake Iseo, which has shown a significant deterioration of water quality conditions since the seventies, and on Lake Garda, the largest Italian lake where EO data have been widely used for many purposes and applications (Giardino et al., 2014). Available ENVISAT-MERIS (2002-2012) and Landsat-8-OLI (2013-on going) imagery has been exploited to produce chlorophyll-a (chl-a) concentration maps, while Landsat-8-TIRS imagery has been used for estimating lake surface temperatures. MERIS images were processed through a neural network (namely the C2R processor, Doerffer et al., 2007), to correct the atmospheric effects and to retrieve water constituents concentration in optically complex deep waters. With regard to L8's images, some atmospheric correctors (e.g. ACOLITE and 6SV) were tested and validated to indentify, for each of the two lakes, the more accurate

Terrestrial Cosmogenic-Nuclide Dating of Alluvial Fans in Death Valley, California

Science.gov (United States)

Machette, Michael N.; Slate, Janet L.; Phillips, Fred M.

2008-01-01

We have used terrestrial cosmogenic nuclides (TCN) to establish the age of some of the most extensive Quaternary alluvial fans in Death Valley, California. These intermediate-age alluvial fans are most extensive on the western side of the valley, where tectonic deformation is considerably less pronounced than on the eastern side of the valley. These fans are characterized by a relatively smooth, densely packed desert pavement formed by well-varnished (blackened) clasts. These surfaces have been mapped as the Q2 gravel by previous workers and as unit Qai (intermediate age) by us. However, the intermediate-age gravels probably contain multiple subunits, as evidenced by slight differences in morphologic expression, soil formation, and inset geomorphic relations. The TCN technique used herein sums the cosmogenic 36Cl in approximately 2.5-meter-deep profiles through soil and host alluvium, thus avoiding some of the problems associated with the more typical surface-exposure dating of boulders or smaller clasts. Our TCN 36Cl dating of 12 depth profiles indicates that these intermediate-age (Qai) alluvial fans range from about 100 to 40 kilo-annum (ka), with a mean age of about 70 ka. An alternative interpretation is that alluvial unit Qai was deposited in two discrete episodes from 90 to 80 ka and from 60 to 50 ka, before and after MIS (marine oxygen-isotope stage) 4 (respectively). Without an intermediate-age unit, such as MIS 4 lake deposits, we can neither disprove nor prove that Qai was deposited in two discrete intervals or over a longer range of time. Thus, in Death Valley, alluvial unit Qai largely brackets MIS 4, which is not associated with a deep phase of Lake Manly. These Qai fans extend to elevations of about -46 meters (150 feet below sea level) and have not been transgressed by Lake Manly, suggesting that MIS 4 or MIS 2 lakes were rather shallow in Death Valley, perhaps because they lacked inflow from surface runoff of the Sierra Nevada drainages through

Potentially dangerous glacial lakes in Kyrgyzstan - Research overview of 2004-2015

Science.gov (United States)

Jansky, Bohumir; Yerokhin, Sergey; Sobr, Miroslav; Engel, Zbynek; Cerny, Michal; Falatkova, Kristyna; Kocum, Jan; Benes, Vojtech

2016-04-01

Global warming causes intensive melting and retreat of glaciers in most of high mountains all over the world. This process is also evident in the mountain regions of central Tien Shan. Glacier melt water affects changes in hydrological regime of water streams and causes overfilling of high mountain lake basins. The dams of many lakes are very unstable and can burst open. To determine the degree of such risk, it is necessary to analyse the genesis of lakes, to characterize the morphology of the lake basins and to know the particularities of their hydrological regime. According to the latest inventory within territory of Kyrgyzstan, a total of 1328 lakes have been identified as potentially dangerous, 12 lakes are considered as currently dangerous, other 25 feature high potential hazard. Since 1952 more than 70 disastrous cases of lake outburst have been registered. The hazardous alpine lakes are studied in Kyrgyzstan systematically since 1966. Since 2004, Czech-Kyrgyz research team has been operating in Kyrgyzstan in the field of dangerous glacial lakes. Projects were focused primarily on high-mountain glacial lakes risk assessment, propositions of risk mitigation measures, establishment of permanent research station near one of the studied glacier complexes, preparation of risk analysis for selected endangered valleys, evaluation of climatic and hydrological data and glacier development within observed regions. The most significant portion of data and information has been gathered during field work, complemented by satellite image analysis and surveillance flights over the monitored sites.

Evaluation of Water Quality Change of Brackish Lake in Snowy Cold Regions Accompanying Climate Change

Science.gov (United States)

Kudo, K.; Hasegawa, H.; Nakatsugawa, M.

2017-12-01

This study addresses evaluation of water quality change of brackish lake based on the estimation of hydrological quantities resulting from long-term hydrologic process accompanying climate change. For brackish lakes, such as Lake Abashiri in Eastern Hokkaido, there are concerns about water quality deterioration due to increases in water temperature and salinity. For estimating some hydrological quantities in the Abashiri River basin, including Lake Abashiri, we propose the following methods: 1) MRI-NHRCM20, a regional climate model based on the Representative Concentration Pathways adopted by IPCC AR5, 2) generalized extreme value distribution for correcting bias, 3) kriging adopted variogram for downscaling and 4) Long term Hydrologic Assessment model considering Snow process (LoHAS). In addition, we calculate the discharge from Abashiri River into Lake Abashiri by using estimated hydrological quantities and a tank model, and simulate impacts on water quality of Lake Abashiri due to climate change by setting necessary conditions, including the initial conditions of water temperature and water quality, the pollution load from the inflow rivers, the duration of ice cover and salt pale boundary. The result of the simulation of water quality indicates that climate change is expected to raise the water temperature of the lake surface by approximately 4°C and increase salinity of surface of the lake by approximately 4psu, also if salt pale boundary in the lake raises by approximately 2-m, the concentration of COD, T-N and T-P in the bottom of the lake might increase. The processes leading to these results are likely to be as follows: increased river water flows in along salt pale boundary in lake, causing dynamic flow of surface water; saline bottom water is entrained upward, where it mixes with surface water; and the shear force acting at salt pale boundary helps to increase the supply of salts from bottom saline water to the surface water. In the future, we will

Submerged Grove in Lake Onogawa

OpenAIRE

Sato, Yasuhiro; Nakamura, Soken; Ochiai, Masahiro

1996-01-01

Abstract : The first record by ultrasonic echo sounding on the distribution of the submerged standing trees on the bottom of Lake Onogawa is presented. Lake Onogawa is a dammed lake formed at the time of the eruption of the volcano Mt.Bandai in 1888. Since then the original vegetation of the dammed valley has remained submerged. Many submerged standing trees are distributed on the bottom within about 600m from the northeast end of the lake. The density of the trees in this area is sufficient ...

Tracing the sources of PCDD/Fs and PCBs in Lake Baikal

Energy Technology Data Exchange (ETDEWEB)

Mamontov, A.A.; Mamontova, E.A.; Tarasova, E.N.; McLachlan, M.S.

2000-03-01

Lake Baikal is a unique freshwater ecosystem that has been declared a UNESCO World Heritage Site. It contains high levels of PCBs, and Baikal seal were recently found to have PCDD/F concentrations comparable to those in the Baltic Sea. In this work fish and soil were analyzed to trace the sources of these compounds to the lake. The fish samples indicated that the PCDD/F and PCB contamination of Lake Baikal does not originate from background inputs and that the contamination increases from north to south. The soil inventory was determined at 34 sites around Lake Baikal and in the Angara River valley. For the PCDD/Fs and most PCBs, the soil inventory is a good approximation of the cumulative atmospheric deposition. It varied over a factor of 1,000, with the highest levels in Usol'ye Sibirskoe, a city 110 km north of the southwestern tip of the lake in the highly industrialized Angara River valley, and the lowest values in the pristine areas to the northeast of the lake. A continuous decrease in the soil inventory was observed moving from Usol'ye S. up the Angara River valley to Lake Baikal and from there northeastward along the lake.

Spatial risk modelling for water shortage and nitrate pollution in the lower Jordan valley

International Nuclear Information System (INIS)

Loibl, W.; Orthofer, R.

2002-02-01

This report summarizes the results of the spatial risk modeling activities (work package WP-4.4, 'GIS Risk Modeling') of the INCO-DC project 'Developing Sustainable Water Management in the Jordan Valley'. The project was funded by European Commission's INCO-DC research program. The main objective of the project was to develop the scientific basis for an integral management plan of water resources and their use in the Lower Jordan Valley. The outputs of the project were expected to allow a better understanding of the water management situation, and to provide a sound basis for a better future water management - not only separately in the three countries, but in the overall valley region. The risk modeling was done by the ARCS Seibersdorf research (ARCS), based on information and data provided by the regional partners from Israel (Hebrew University, Jerusalem, HUJ), Palestine (Applied Research Institute, Jerusalem, Bethlehem, ARIJ) and Jordan (EnviroConsult Office, Amman, ECO). The land use classification has been established through a cooperation between ARCS and the Yale University Center for Earth Observation (YUCEO). As a result of the work, the spatial patterns of agricultural and domestic water demand in the Lower Jordan Valley were established, and the spatial dimension of driving forces for water usage and water supply was analyzed. Furthermore, a conceptual model for nitrate leakage (established by HUJ) was translated into a GIS system, and the risks for nitrate pollution of groundwater were quantified. (author)

Ground-Water Budgets for the Wood River Valley Aquifer System, South-Central Idaho, 1995-2004

Science.gov (United States)

Bartolino, James R.

2009-01-01

The Wood River Valley contains most of the population of Blaine County and the cities of Sun Valley, Ketchum, Haley, and Bellevue. This mountain valley is underlain by the alluvial Wood River Valley aquifer system which consists of a single unconfined aquifer that underlies the entire valley, an underlying confined aquifer that is present only in the southernmost valley, and the confining unit that separates them. The entire population of the area depends on ground water for domestic supply, either from domestic or municipal-supply wells, and rapid population growth since the 1970s has caused concern about the long-term sustainability of the ground-water resource. To help address these concerns this report describes a ground-water budget developed for the Wood River Valley aquifer system for three selected time periods: average conditions for the 10-year period 1995-2004, and the single years of 1995 and 2001. The 10-year period 1995-2004 represents a range of conditions in the recent past for which measured data exist. Water years 1995 and 2001 represent the wettest and driest years, respectively, within the 10-year period based on precipitation at the Ketchum Ranger Station. Recharge or inflow to the Wood River Valley aquifer system occurs through seven main sources (from largest to smallest): infiltration from tributary canyons, streamflow loss from the Big Wood River, areal recharge from precipitation and applied irrigation water, seepage from canals and recharge pits, leakage from municipal pipes, percolation from septic systems, and subsurface inflow beneath the Big Wood River in the northern end of the valley. Total estimated mean annual inflow or recharge to the aquifer system for 1995-2004 is 270,000 acre-ft/yr (370 ft3/s). Total recharge for the wet year 1995 and the dry year 2001 is estimated to be 270,000 acre-ft/yr (370 ft3/s) and 220,000 acre-ft/yr (300 ft3/s), respectively. Discharge or outflow from the Wood River Valley aquifer system occurs through

Mercury and water level fluctuations in lakes of northern Minnesota

Science.gov (United States)

Larson, James H.; Maki, Ryan P; Christensen, Victoria G.; Sandheinrich, Mark B.; LeDuc, Jaime F.; Kissane, Claire; Knights, Brent C.

2017-01-01

Large lake ecosystems support a variety of ecosystem services in surrounding communities, including recreational and commercial fishing. However, many northern temperate fisheries are contaminated by mercury. Annual variation in mercury accumulation in fish has previously been linked to water level (WL) fluctuations, opening the possibility of regulating water levels in a manner that minimizes or reduces mercury contamination in fisheries. Here, we compiled a long-term dataset (1997-2015) of mercury content in young-of-year Yellow Perch (Perca flavescens) from six lakes on the border between the U.S. and Canada and examined whether mercury content appeared to be related to several metrics of WL fluctuation (e.g., spring WL rise, annual maximum WL, and year-to-year change in maximum WL). Using simple correlation analysis, several WL metrics appear to be strongly correlated to Yellow Perch mercury content, although the strength of these correlations varies by lake. We also used many WL metrics, water quality measurements, temperature and annual deposition data to build predictive models using partial least squared regression (PLSR) analysis for each lake. These PLSR models showed some variation among lakes, but also supported strong associations between WL fluctuations and annual variation in Yellow Perch mercury content. The study lakes underwent a modest change in WL management in 2000, when winter WL minimums were increased by about 1 m in five of the six study lakes. Using the PLSR models, we estimated how this change in WL management would have affected Yellow Perch mercury content. For four of the study lakes, the change in WL management that occurred in 2000 likely reduced Yellow Perch mercury content, relative to the previous WL management regime.

Preliminary assessment of the impact of fluctuating water levels on northern pike in Reindeer Lake

International Nuclear Information System (INIS)

Chen, M.

1993-03-01

Reindeer Lake in north eastern Saskatchewan regulates water levels for the Island Falls hydroelectric power plant. Since inception of the Whitesand Dam on the lake, there have been concerns that fluctuating water levels could be adversely impacting the habitat and population of northern pike in the lake. The extent of water level fluctuations during the pike spawning period of Reindeer Lake and its effect on spawning success was investigated. Since construction of the Whitesand Dam in 1942 Reindeer Lake water levels have averaged ca 1.71 m higher than had the dam not existed, creating ca 430 km 2 of new surface area. Much of this area is shallow water and prone to growth of aquatic vegetation, which is suitable spawning and nursery habitat for northern pike. Annual and periodic water level fluctuations of Reindeer Lake have been higher than under natural conditions. During northern pike spawning and nursing periods, water levels in the lake have generally increased, in 60 out of 64 y. It is concluded that operation of the dam has not caused any direct negative impacts on the northern pike habitat in the lake. 2 refs., 4 figs., 4 tabs

Factors affecting ground-water exchange and catchment size for Florida lakes in mantled karst terrain

Science.gov (United States)

Lee, Terrie Mackin

2002-01-01

In the mantled karst terrain of Florida, the size of the catchment delivering ground-water inflow to lakes is often considerably smaller than the topographically defined drainage basin. The size is determined by a balance of factors that act individually to enhance or diminish the hydraulic connection between the lake and the adjacent surficial aquifer, as well as the hydraulic connection between the surficial aquifer and the deeper limestone aquifer. Factors affecting ground-water exchange and the size of the ground-water catchment for lakes in mantled karst terrain were examined by: (1) reviewing the physical and hydrogeological characteristics of 14 Florida lake basins with available ground-water inflow estimates, and (2) simulating ground-water flow in hypothetical lake basins. Variably-saturated flow modeling was used to simulate a range of physical and hydrogeologic factors observed at the 14 lake basins. These factors included: recharge rate to the surficial aquifer, thickness of the unsaturated zone, size of the topographically defined basin, depth of the lake, thickness of the surficial aquifer, hydraulic conductivity of the geologic units, the location and size of karst subsidence features beneath and onshore of the lake, and the head in the Upper Floridan aquifer. Catchment size and the magnitude of ground-water inflow increased with increases in recharge rate to the surficial aquifer, the size of the topographically defined basin, hydraulic conductivity in the surficial aquifer, the degree of confinement of the deeper Upper Floridan aquifer, and the head in the Upper Floridan aquifer. The catchment size and magnitude of ground-water inflow increased with decreases in the number and size of karst subsidence features in the basin, and the thickness of the unsaturated zone near the lake. Model results, although qualitative, provided insights into: (1) the types of lake basins in mantled karst terrain that have the potential to generate small and large

Great Lakes waters: radiation dose commitments, potential health effects, and cost-benefit considerations

International Nuclear Information System (INIS)

Ainsworth, E.J.

1977-07-01

In 1972, a Great Lakes Water Quality Agreement was signed by the United States and Canadian Governments. It was stipulated that the operation and effectiveness of the agreement were to be reviewed comprehensively in 1977. Aspects of the agreement concern nondegradation of Great Lakes waters and maintenance of levels of radioactivity or other potential pollutants at levels considered as low as practicable. A refined radioactivity objective of one millirem is proposed in the Water Quality Agreement. The implications of adoption of this objective are not known fully. The Division of Environmental Impact Studies was commissioned by ERDA's Division of Technology Overview to summarize the information available on the current levels of radioactivity in Great Lakes waters, compute radiation-dose commitment (integrated dose over 50 years after consumption of 2.2 liters of water of one year), and to comment on the feasibility and cost-benefit considerations associated with the refined one-millirem objective. Current levels of radioactivity in the waters of Lakes Michigan, Ontario, Erie, and Huron result in dose commitments in excess of 1 mrem for whole body and 6 mrem for bone. Future projections of isotope concentrations in Great lakes water indicate similar dose commitments for drinking water in the year 2050. Reduction of the levels of radioactivity in Great Lakes waters is not feasible, but cost-benefit considerations support removal of 226 Ra and 90 Sr through interceptive technology before water consumption. Adoption of the one-millirem objective is not propitious

Lake Urmia (Iran): can future socio-ecologically motivated river basin management restore lake water levels in an arid region with extensive agricultural development?

Science.gov (United States)

Fazel, Nasim; Berndtsson, Ronny; Bertacchi Uvo, Cintia; Klove, Bjorn; Madani, Kaveh

2015-04-01

Lake Urmia, one of the world's largest hyper saline lakes located in northwest of Iran, is a UNESCO Biosphere Reserve and Ramsar site, protected as a national park and, supports invaluable and unique biodiversity and related ecosystem services for the region's 6.5 million inhabitants. Due to increased development of the region's water resources for agriculture and industry and to a certain extent climate change, the lake has started to shrink dramatically since 1995 and now is holding less than 30 percent of its volume. Rapid development in agricultural sector and land-use changes has resulted in immense construction of dams and water diversions in almost all lake feeding rivers, intensifying lake shrinking, increasing salinity and degrading its ecosystem. Recently, lake's cultural and environmental importance and social pressure has raised concerns and brought government attention to the lake restoration plans. Along with poor management, low yield agriculture as the most water consuming activity in the region with, rapid, insufficient development is one of the most influential drivers in the lake desiccation. Part of the lake restoration plans in agricultural sector is to restrict the agricultural areas in the main feeding river basins flowing mostly in the southern part of the lake and decreasing the agricultural water use in this area. This study assess the efficiency and effectiveness of the proposed plans and its influence on the lake level rise and its impacts on economy in the region using a system dynamics model developed for the Lake consist of hydrological and agro-economical sub-systems. The effect of decrease in agricultural area in the region on GDP and region economy was evaluated and compared with released water contribution in lake level rise for a five year simulation period.

Hydrogeology and water quality of the Shell Valley Aquifer, Rolette County, North Dakota

Science.gov (United States)

Strobel, M.L.

1997-01-01

The Shell Valley aquifer is the sole source of water for the city of Belcourt and the primary source of water for most of the Turtle Mountain Indian Reservation. The Turtle Mountain Band of Chippewa Indians is concerned about the quantity and quality of water in the Shell Valley aquifer, which underlies about 56 square miles in central Rolette County and has an average saturated thickness of about 35 feet. Water levels across most of the Shell Valley aquifer fluctuate with variations in precipitation but generally are stable. Withdrawals from the north well field decreased slightly during 1976-95, but withdrawals from the south well field increased during 1983-95. Water levels in the south well field declined as withdrawals increased. The average decline during the last 8 years was about 1.75 feet per year. The water level has reached the well screen in at least one of the production wells. Most of the water in the aquifer is a bicarbonate type and has dissolved-solids concentrations ranging from 479 to 1,510 milligrams per liter. None of the samples analyzed had detectable concentrations of pesticides, but hydrocarbons were detected in both ground- and surfacewater samples. Polycyclic aromatic hydrocarbons (PAH) were the most frequently detected hydrocarbons. Benzene, toluene, ethylbenzene, and xylene (BTEX), polychlorinated biphenyls (PCB), and pentachlorophenol (PCP) also were detected.Generally, the Shell Valley aquifer is an adequate source of water for current needs, but evaluation of withdrawals in relation to a knowledge of aquifer hydrology would be important in quantifying sustainable water supplies. Water quality in the aquifer generally is good; the Turtle Mountain Band of Chippewa Indians filters the water to reduce concentrations of dissolved constituents. Hydrocarbons, although present in the aquifer, have not been quantified and may not pose a general health risk. Further analysis of the quantity and distribution of the hydrocarbons would be useful

Cyanobacteria and cyanotoxins in the source water from Lake ...

African Journals Online (AJOL)

The phytoplankton community and cyanotoxins in Lake Chivero (formerly Lake McIlwaine) and the presence of cyanotoxins in treated drinking water were investigated between 2003 and 2004. A typical seasonal succession of Cyanobacteria species occurred from January to April, Bacillariophyta from May to July, and ...

Climate change and water quality in the Great Lakes Basin

Energy Technology Data Exchange (ETDEWEB)

NONE

2003-08-01

The Great Lakes Basin is subjected to several stresses, such as land use changes, chemical contamination, nutrient over-enrichment, alien invasive species, and acid precipitation. Climate change is now added to this list. The Water Quality Board was asked to provide advice concerning the impacts of climate change on the water quality of the Great Lakes and on how to address the issue. A White Paper was commissioned by the Board to address four key questions: (1) what are the Great Lakes water quality issues associated with climate change, (2) what are potential impacts of climate change on beneficial uses, (3) how might impacts vary across the Great Lakes region, and (4) what are the implications for decision making. The conclusions and findings of the White Paper were then discussed at a workshop held in May 2003. Part 1 of the document provides an executive summary. The advice of the Water Quality Board was based on the findings of the White Paper and presented in Part 2. Part 3 presented the White Paper, while a summary of the workshop was provided in Part 4. A presentation on cross border tools and strategies was also presented by a workshop participant.

Catastrophic flooding origin of shelf valley systems in the English Channel.

Science.gov (United States)

Gupta, Sanjeev; Collier, Jenny S; Palmer-Felgate, Andy; Potter, Graeme

2007-07-19

Megaflood events involving sudden discharges of exceptionally large volumes of water are rare, but can significantly affect landscape evolution, continental-scale drainage patterns and climate change. It has been proposed that a significant flood event eroded a network of large ancient valleys on the floor of the English Channel-the narrow seaway between England and France. This hypothesis has remained untested through lack of direct evidence, and alternative non-catastrophist ideas have been entertained for valley formation. Here we analyse a new regional bathymetric map of part of the English Channel derived from high-resolution sonar data, which shows the morphology of the valley in unprecedented detail. We observe a large bedrock-floored valley that contains a distinct assemblage of landforms, including streamlined islands and longitudinal erosional grooves, which are indicative of large-scale subaerial erosion by high-magnitude water discharges. Our observations support the megaflood model, in which breaching of a rock dam at the Dover Strait instigated catastrophic drainage of a large pro-glacial lake in the southern North Sea basin. We suggest that megaflooding provides an explanation for the permanent isolation of Britain from mainland Europe during interglacial high-sea-level stands, and consequently for patterns of early human colonisation of Britain together with the large-scale reorganization of palaeodrainage in northwest Europe.

Assessment of microcystins in lake water and fish (Mugilidae, Liza sp.) in the largest Spanish coastal lake.

Science.gov (United States)

Romo, Susana; Fernández, Francisca; Ouahid, Youness; Barón-Sola, Ángel

2012-01-01

Cyanobacteria dominance and cyanotoxin production can become major threats to humans and aquatic life, especially in warm shallow lakes, which are often dominated by cyanobacteria. This study investigates the occurrence and distribution of microcystins (MCYST) in water, cell-bound and in the tissues of the commercial mugilid Liza sp. in the largest, coastal, Spanish Mediterranean lake (Albufera of Valencia). This is the first report concerning microcystin accumulation in tissues of mugilid fish species. Considerable amounts of microcystins were found in the water and seston, which correlated with development of Microcystis aeruginosa populations in the lake. The MCYST concentrations found in Lake Albufera (mean 1.7 and 17 μg/L and maximum 16 and 120 μg/L in water and seston, respectively) exceeded by one to two orders of magnitude the guideline levels proposed by the World Health Organization and were higher than that reported in other lakes of the Mediterranean zone. The presence of MCYST was found in all the fishes studied and accumulated differently among tissues of the commercial species Liza sp. Toxin accumulation in fish tissues showed that although the target organ for MCYST was the liver, high concentrations of microcystins were also found in other analysed tissues (liver>intestine>gills>muscle). Human tolerable daily intake for microcystins is assessed relative to the WHO guidelines, and potential toxicological risks for humans, wildlife and related ecosystems of the lake are discussed.

Applying a water quality index model to assess the water quality of the major rivers in the Kathmandu Valley, Nepal.

Science.gov (United States)

Regmi, Ram Krishna; Mishra, Binaya Kumar; Masago, Yoshifumi; Luo, Pingping; Toyozumi-Kojima, Asako; Jalilov, Shokhrukh-Mirzo

2017-08-01

Human activities during recent decades have led to increased degradation of the river water environment in South Asia. This degradation has led to concerns for the populations of the major cities of Nepal, including those of the Kathmandu Valley. The deterioration of the rivers in the valley is directly linked to the prevalence of poor sanitary conditions, as well as the presence of industries that discharge their effluents into the river. This study aims to investigate the water quality aspect for the aquatic ecosystems and recreation of the major rivers in the Kathmandu Valley using the Canadian Council of Ministers of the Environment water quality index (CCME WQI). Ten physicochemical parameters were used to determine the CCME WQI at 20 different sampling locations. Analysis of the data indicated that the water quality in rural areas ranges from excellent to good, whereas in denser settlements and core urban areas, the water quality is poor. The study results are expected to provide policy-makers with valuable information related to the use of river water by local people in the study area.

Hydro-meteorological trends in the Gidabo catchment of the Rift Valley Lakes Basin of Ethiopia

Science.gov (United States)

Belihu, Mamuye; Abate, Brook; Tekleab, Sirak; Bewket, Woldeamlak

2018-04-01

The global and regional variability and changes of climate and stream flows are likely to have significant influence on water resource availability. The magnitude and impacts of climate variability and change differs spatially and temporally. This study examines the long term hydroclimatic changes, analyses of the hydro-climate variability and detect whether there exist significant trend or not in the Gidabo catchment, rift valley lakes basin of Ethiopia. Precipitation, temperature and stream flow time series data were used in monthly, seasonal and annual time scales. The precipitation and temperature data span is between 1982 and 2014 and that of stream flow is between 1976 and 2006. To detect trends the analysis were done by using Mann Kendal (MK), Sen's graphical method and to detect change point using the Pettit test. The comparison of trend analysis between MK trend test and Sen graphical method results depict mostly similar pattern. The annual rainfall trends exhibited a significant decrease by about 12 mm per year in the upstream, which is largely driven by the significant decrease in the peak season rainfall. The Pettit test revealed that the years 1997 and 2007 were the change points. It is noted that the rise of temperature over a catchment might have decreased the availability of soil moisture which resulted in less runoff. The temperature analyses also revealed that the catchment was getting warmer; particularly in the upstream. The minimum temperature trend showed a significant increase about 0.08°c per annum. There is generally a decreasing trend in stream flow. The monthly stream flow also exhibited a decreasing trend in February, March and September. The decline in annual and seasonal rainfall and the increase in temperature lead to more evaporation and directly affecting the stream flow negatively. This trend compounded with the growth of population and increasing demand for irrigation water exacerbates the competing demand for water resources. It

Hydrologic models and analysis of water availability in Cuyama Valley, California

Science.gov (United States)

Hanson, R.T.; Flint, Lorraine E.; Faunt, Claudia C.; Gibbs, Dennis R.; Schmid, Wolfgang

2014-01-01

Changes in population, agricultural development practices (including shifts to more water-intensive crops), and climate variability are placing increasingly larger demands on available water resources, particularly groundwater, in the Cuyama Valley, one of the most productive agricultural regions in Santa Barbara County. The goal of this study was to produce a model capable of being accurate at scales relevant to water management decisions that could be considered in the evaluation of the sustainable water supply. The Cuyama Valley Hydrologic Model (CUVHM) was designed to simulate the most important natural and human components of the hydrologic system, including components dependent on variations in climate, thereby providing a reliable assessment of groundwater conditions and processes that can inform water users and help to improve planning for future conditions. Model development included a revision of the conceptual model of the flow system, construction of a precipitation-runoff model using the Basin Characterization Model (BCM), and construction of an integrated hydrologic flow model with MODFLOW-One-Water Hydrologic Flow Model (MF-OWHM). The hydrologic models were calibrated to historical conditions of water and land use and, then, used to assess the use and movement of water throughout the Valley. These tools provide a means to understand the evolution of water use in the Valley, its availability, and the limits of sustainability. The conceptual model identified inflows and outflows that include the movement and use of water in both natural and anthropogenic systems. The groundwater flow system is characterized by a layered geologic sedimentary sequence that—in combination with the effects of groundwater pumping, natural recharge, and the application of irrigation water at the land surface—displays vertical hydraulic-head gradients. Overall, most of the agricultural demand for water in the Cuyama Valley in the initial part of the growing season is

Remotely Sensing Lake Water Volumes on the Inner Arctic Coastal Plain of Northern Alaska

Science.gov (United States)

Simpson, C. E.; Arp, C. D.; Jones, B. M.; Hinkel, K. M.; Carroll, M.; Smith, L. C.

2017-12-01

Thermokarst lake depth is controlled by the amount of excess ice in near-surface permafrost, with lake depths of about 1 - 3 m in areas of epigenetic permafrost and over 10 m in areas of syngenetic permafrost. An important exception to these general patterns is found on the inner Arctic Coastal Plain (ACP) of northern Alaska, where deep lakes occur in Pleistocene-aged, ground-ice poor sandy terrain. These lakes cover 20% of the currently inactive sand sheet and dune deposit (referred to as the Pleistocene Sand Sea) that comprises approximately 7000 km2 of the ACP. Surrounded by high and eroding bluffs, sand sea lakes lie in natural depressions and are characterized by wide, shallow littoral shelves and central troughs that are typically oriented NNW to SSE and can reach depths greater than 20 m. Despite their unique form and extensive coverage, these lakes have received little prior study and a literature gap remains regarding regional water storage. This research classifies sand sea lakes, estimates individual lake volume, and provides a first quantification of water storage in a region of the lake-dominated ACP. We measured bathymetric profiles in 19 sand sea lakes using a sonar recorder to capture various lake depth gradients. Bathymetric surveys collected by oil industry consultants, lake monitoring programs, and habitat studies serve as additional datasets. These field measured lake depth data points were used to classify Color Infrared Photography, WorldView-2 satellite imagery, and Landsat-OLI satellite imagery to develop a spectral depth-classification algorithm and facilitate the interpolation of the bathymetry for study lakes in the inner ACP. Finally, we integrate the remotely sensed bathymetry and imagery-derived lake surface area to estimate individual and regional-scale lake volume. In addition to the natural function of these lakes in water storage, energy balance, and habitat provision, the need for winter water supply to build ice roads for oil

Evaluating water conservation and reuse policies using a dynamic water balance model.

Science.gov (United States)

Qaiser, Kamal; Ahmad, Sajjad; Johnson, Walter; Batista, Jacimaria R

2013-02-01

A dynamic water balance model is created to examine the effects of different water conservation policies and recycled water use on water demand and supply in a region faced with water shortages and significant population growth, the Las Vegas Valley (LVV). The model, developed using system dynamics approach, includes an unusual component of the water system, return flow credits, where credits are accrued for returning treated wastewater to the water supply source. In LVV, Lake Mead serves as, both the drinking water source and the receiving body for treated wastewater. LVV has a consumptive use allocation from Lake Mead but return flow credits allow the water agency to pull out additional water equal to the amount returned as treated wastewater. This backdrop results in a scenario in which conservation may cause a decline in the available water supply. Current water use in LVV is 945 lpcd (250 gpcd), which the water agency aims to reduce to 752 lpcd (199 gpcd) by 2035, mainly through water conservation. Different conservation policies focused on indoor and outdoor water use, along with different population growth scenarios, are modeled for their effects on the water demand and supply. Major contribution of this study is in highlighting the importance of outdoor water conservation and the effectiveness of reducing population growth rate in addressing the future water shortages. The water agency target to decrease consumption, if met completely through outdoor conservation, coupled with lower population growth rate, can potentially satisfy the Valley's water demands through 2035.

Evaluating Water Conservation and Reuse Policies Using a Dynamic Water Balance Model

Science.gov (United States)

Qaiser, Kamal; Ahmad, Sajjad; Johnson, Walter; Batista, Jacimaria R.

2013-02-01

A dynamic water balance model is created to examine the effects of different water conservation policies and recycled water use on water demand and supply in a region faced with water shortages and significant population growth, the Las Vegas Valley (LVV). The model, developed using system dynamics approach, includes an unusual component of the water system, return flow credits, where credits are accrued for returning treated wastewater to the water supply source. In LVV, Lake Mead serves as, both the drinking water source and the receiving body for treated wastewater. LVV has a consumptive use allocation from Lake Mead but return flow credits allow the water agency to pull out additional water equal to the amount returned as treated wastewater. This backdrop results in a scenario in which conservation may cause a decline in the available water supply. Current water use in LVV is 945 lpcd (250 gpcd), which the water agency aims to reduce to 752 lpcd (199 gpcd) by 2035, mainly through water conservation. Different conservation policies focused on indoor and outdoor water use, along with different population growth scenarios, are modeled for their effects on the water demand and supply. Major contribution of this study is in highlighting the importance of outdoor water conservation and the effectiveness of reducing population growth rate in addressing the future water shortages. The water agency target to decrease consumption, if met completely through outdoor conservation, coupled with lower population growth rate, can potentially satisfy the Valley's water demands through 2035.

Bacterial diversity and ecological function in lake water bodies

OpenAIRE

Lijuan Ren; Dan He; Peng Xing; Yujing Wang; Qinglong Wu

2013-01-01

The healthy development of lake ecosystems is a global issue. Bacteria are not only an integral component of food webs, but also play a key role in controlling and regulating water quality in lake ecosystems. Hence, in order to provide some suggestions for maintaining the long-term and healthy development of lake ecosystems, this review discusses and analyses concepts and assessment of bacterial diversity, the distribution of bacteria communities, mechanisms of formation, and the ecological f...

The Water Level Fall of Lake Megali Prespa (N Greece): an Indicator of Regional Water Stress Driven by Climate Change and Amplified by Water Extraction?

Science.gov (United States)

van der Schriek, Tim; Giannakopoulos, Christos

2014-05-01

The Mediterranean stands out globally due to its sensitivity to (future) climate change, with future projections predicting an increase in excessive drought events and declining rainfall. Regional freshwater ecosystems are particularly threatened: precipitation decreases, while extreme droughts increase and human impacts intensify (e.g. water extraction, drainage, pollution and dam-building). Many Mediterranean lake-wetland systems have shrunk or disappeared over the past two decades. Protecting the remaining systems is extremely important for supporting global biodiversity and for ensuring sustainable water availability. This protection should be based on a clear understanding of lake-wetland hydrological responses to natural and human-induced changes, which is currently lacking in many parts of the Mediterranean. The interconnected Prespa-Ohrid Lake system is a global hotspot of biodiversity and endemism. The unprecedented fall in water level (~8m) of Lake Megali Prespa threatens this system, but causes remain debated. Modelling suggests that the S Balkan will experience rainfall and runoff decreases of ~30% by 2050. However, projections revealing the potential impact of these changes on future lake level are unavailable as lake regime is not understood. A further drop in lake level may have serious consequences. The Prespa Lakes contribute ~25% of the total inflow into Lake Ohrid through underground karst channels; falling lake levels decrease this discharge. Lake Ohrid, in turn, feeds the Drim River. This entire catchment may therefore be affected by falling lake levels; its water resources are of great importance for Greece, Albania, FYROM and Montenegro (e.g. tourism, agriculture, hydro-energy, urban & industrial use). This new work proves that annual water level fluctuations of Lake Megali Prespa are predominantly related to precipitation during the first 7 months (Oct-Apr) of the hydrological year (Oct-Sep). Lake level is very sensitive to regional and

Ground-water quality in the southeastern Sacramento Valley aquifer, California, 1996

Science.gov (United States)

Milby Dawson, Barbara J.

2001-01-01

In 1996, the U.S. Geological Survey sampled 29 domestic wells and 2 monitoring wells in the southeastern Sacramento Valley as part of the U.S. Geological Survey's National Water-Quality Assessment (NAWQA) Program. This area, designated as the NAWQA Sacramento subunit study area, was chosen because it had the largest amount of ground-water use in the Sacramento River Basin. The Sacramento subunit study area is about 4,400 square kilometers and includes intense agricultural and urban development. The wells sampled ranged from 14.9 to 79.2 meters deep. Ground-water samples from 31 wells were analyzed for 6 field measurements, 14 inorganic constituents, 6 nutrient constituents, organic carbon, 86 pesticides, 87 volatile organic compounds, tritium (hydrogen-3), radon-222, deuterium (hydrogen-2), and oxygen-18. Nitrate levels were lower than the 2000 drinking-water standards in all but one well, but many detections were in the range that indicated an effect by human activities on ground-water quality. Radon was detected in all wells, and was measured at levels above the proposed Federal 2000 maximum contaminant level in 90 percent of the wells. Five pesticides and one pesticide degradation product were detected in ground-water samples and concentrations were below 2000 drinking-water standards. All pesticides detected during this study have been used in the Sacramento Valley. Thirteen volatile organic compounds were detected in ground water. One detection of trichloroethene was above Federal 2000 drinking-water standards, and another, tetrachloromethane, was above California 1997 drinking-water standards; both occurred in a well that had eight volatile organic compound detections and is near a known source of ground-water contamination. Pesticides and volatile organic compounds were detected in agricultural and urban areas; both pesticides and volatile organic compounds were detected at a higher frequency in urban wells. Ground-water chemistry indicates that natural

Triple Isotope Water Measurements of Lake Untersee Ice using Off-Axis ICOS

Science.gov (United States)

Berman, E. S.; Huang, Y. W.; Andersen, D. T.; Gupta, M.; McKay, C. P.

2015-12-01

Lake Untersee (71.348°S, 13.458°E) is the largest surface freshwater lake in the interior of the Gruber Mountains of central Queen Maud Land in East Antarctica. The lake is permanently covered with ice, is partly bounded by glacier ice and has a mean annual air temperature of -10°C. In contrast to other Antarctic lakes the dominating physical process controlling ice-cover dynamics is low summer temperatures and high wind speeds resulting in sublimation rather than melting as the main mass-loss process. The ice-cover of the lake is composed of lake-water ice formed during freeze-up and rafted glacial ice derived from the Anuchin Glacier. The mix of these two fractions impacts the energy balance of the lake, which directly affects ice-cover thickness. Ice-cover is important if one is to understand the physical, chemical, and biological linkages within these unique, physically driven ecosystems. We have analyzed δ2H, δ18O, and δ17O from samples of lake and glacier ice collected at Lake Untersee in Dec 2014. Using these data we seek to answer two specific questions: Are we able to determine the origin and history of the lake ice, discriminating between rafted glacial ice and lake water? Can isotopic gradients in the surface ice indicate the ablation (sublimation) rate of the surface ice? The triple isotope water analyzer developed by Los Gatos Research (LGR 912-0032) uses LGR's patented Off-Axis ICOS (Integrated Cavity Output Spectroscopy) technology and incorporates proprietary internal thermal control for high sensitivity and optimal instrument stability. This analyzer measures δ2H, δ18O, and δ17O from water, as well as the calculated d-excess and 17O-excess. The laboratory precision in high performance mode for both δ17O and δ18O is 0.03 ‰, and for δ2H is 0.2 ‰. Methodology and isotope data from Lake Untersee samples are presented. Figure: Ice samples were collected across Lake Untersee from both glacial and lake ice regions for this study.

Assessing trends in fishery resources and lake-water aluminum from paleolimnological analyses of siliceous algae

International Nuclear Information System (INIS)

Kingston, J.C.; Birks, H.J.B.; Uutala, A.J.; Cummings, B.F.; Smol, J.P.

1992-01-01

Lake water aluminum concentrations have a significant influence on the composition of microfossil assemblages of diatoms and chrysophytes deposited in lake sediments. With the paleolimnological approach of multilake datasets in the Adirondack region of New York, USA, the authors use canonical correspondence analysis to describe past trends in lake water Al. Four lakes, previously investigated regarding acidification and fishery trends, are used to demonstrate that paleolimnological assessment can also provide direction, timing, and magnitude of trends for both toxic metals and fish resources. Additionally, the authors use weighted average regression and calibration to obtain quantitative reconstructions of past lake water Al concentrations. Such reconstructions provide further insight into fishery resource damage and can be compared with modelling results. According to paleolimnological reconstructions, some of the naturally most acidic lakes in the Adirondack region had preindustrial lake water concentrations of inorganic monomeric Al near 4/micromol times L. Although these high concentrations are surprising from a geochemical point of view, they may partially explain the preindustrial absence of fish, as has been independently determined by paleolimnological analysis of phantom midges (Chaoborus). Fishery resource deterioration in acidified Adirondack lakes was coincident with major increases in lake water Al concentrations

Water resources of the Lake Erie shore region in Pennsylvania

Science.gov (United States)

Mangan, John William; Van Tuyl, Donald W.; White, Walter F.

1952-01-01

An abundant supply of water is available to the Lake Erie Shore region in Pennsylvania. Lake i£rie furnishes an almost inexhaustible supply of water of satisfactory chemical quality. Small quantities of water are available from small streams in the area and from the ground. A satisfactory water supply is one of the factors that affect the economic growth of a region. Cities and towns must have adequate amounts of pure water for human consumption. Industries must have suitable water ih sufficient quantities for all purposes. In order to assure. success and economy, the development of water resources should be based on adequate knowledge of the quantity and quality of the water. As a nation, we can not afford to run the risk of dissipating our resources, especially in times of national emergency, by building projects that are not founded on sound engineering and adequate water-resources information. The purpose of this report is to summarize and interpret all available water-resources information for the Lake Erie Shore region in Pennsylvania. The report will be useful for initial guidance in the location or expansion of water facilities for defense and nondefense industries and the municipalities upon which they are dependent. It will also be useful in evaluating the adequacy of the Geological Survey's part of the basic research necessary to plan the orderly development of the water resources of the Lake Erie Shore region. Most of the data contained inthis report have been obtained'by the U. S. Geological Survey in cooperation with the Pennsylvania Department of Forests and Waters, the Pennsylvania Department of Internal Affairs, and the Pennsylvania State Planning Board, Department of Commerce. The Pennsylv~nia Department of Health furnished information on water pollution. The report was prepared in the Water Resources Division of the U. S. Geological Survey b:y John W. Mangan (Surface Water). Donald W. VanTuyl (Ground Water). and Walter F. White, Jr. (Quality of

Water sampling using a drone at Yugama crater lake, Kusatsu-Shirane volcano, Japan

Science.gov (United States)

Terada, Akihiko; Morita, Yuichi; Hashimoto, Takeshi; Mori, Toshiya; Ohba, Takeshi; Yaguchi, Muga; Kanda, Wataru

2018-04-01

Remote sampling of water from Yugama crater lake at Kusatsu-Shirane volcano, Japan, was performed using a drone. Despite the high altitude of over 2000 m above sea level, our simple method was successful in retrieving a 250 mL sample of lake water. The procedure presented here is easy for any researcher to follow who operates a drone without additional special apparatus. We compare the lake water sampled by drone with that sampled by hand at a site where regular samplings have previously been carried out. Chemical concentrations and stable isotope ratios are largely consistent between the two techniques. As the drone can fly automatically with the aid of navigation by Global Navigation Satellite System (GNSS), it is possible to repeatedly sample lake water from the same location, even when entry to Yugama crater lake is restricted due to the risk of eruption.[Figure not available: see fulltext.

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

Directory of Open Access Journals (Sweden)

Cieśliński Roman

2016-12-01

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.

Devils Lake Climate, Weather, and Water Decision Support System

Science.gov (United States)

Horsfall, F. M.; Kluck, D. R.; Brewer, M.; Timofeyeva, M. M.; Symonds, J.; Dummer, S.; Frazier, M.; Shulski, M.; Akyuz, A.

2010-12-01

North Dakota’s Devils Lake area represents an example of a community struggling with a serious climate-related problem. The Devils Lake water level elevation has been rising since 1993 due to a prolonged wet period, and it is now approaching the spill stage into the Cheyenne River and ultimately into the Red River of the North. The impacts of the rising water have already caused significant disruption to the surrounding communities, and even greater impacts will be seen if the lake reaches the spill elevation. These impacts include flooding, water quality issues, impacts to agriculture and ecosystems, and impacts to local and regional economies. National Oceanic and Atmospheric Administration (NOAA), through the National Weather Service (NWS), the National Environmental Satellite, Data, and Information Service (NESDIS), and the Office of Oceanic and Atmospheric Research (OAR), provides the U.S. public with climate, water, and weather services, including meteorological, hydrological and climate data, warnings, and forecasts of weather and climate from near- to longer-term timescales. In support of the people of Devils Lake, the surrounding communities, the people of North Dakota, and the other Federal agencies with responsibilities in the area, NOAA launched the first ever climate-sensitive decision support web site (www.devilslake.noaa.gov) in July 2010. The website is providing integrated weather, water, and climate information for the area, and has links to information from other agencies, such as USGS, to help decision makers as they address this ongoing challenge. This paper will describe the website and other ongoing activities by NOAA in support of this community.

Snake River Sockeye Salmon Sawtooth Valley Project Conservation and Rebuilding Program : Supplemental Fnal Environmental Assessment.

Energy Technology Data Exchange (ETDEWEB)

United States. Bonneville Power Administration.

1995-03-01

This document announces Bonneville Power Administration`s (BPA) proposal to fund three separate but interrelated actions which are integral components of the overall Sawtooth Valley Project to conserve and rebuild the Snake River Sockeye salmon run in the Sawtooth Valley of south-central Idaho. The three actions are as follows: (1) removing a rough fish barrier dam on Pettit Lake Creek and constructing a weir and trapping facilities to monitor future sockeye salmon adult and smolt migration into and out of Pettit Lake; (2) artificially fertilizing Readfish Lake to enhance the food supply for Snake River sockeye salmon juveniles released into the lake; and (3) trapping kokanee fry and adults to monitor the fry population and to reduce the population of kokanee in Redfish Lake. BPA has prepared a supplemental EA (included) which builds on an EA compled in 1994 on the Sawtooth Valley Project. Based on the analysis in this Supplemental EA, BPA has determined that the proposed actions are not major Federal actions significantly affecting the quality of the human environment. Therefore an Environmental Impact Statement is not required.

Water quality monitoring: A comparative case study of municipal and Curtin Sarawak's lake samples

Science.gov (United States)

Anand Kumar, A.; Jaison, J.; Prabakaran, K.; Nagarajan, R.; Chan, Y. S.

2016-03-01

In this study, particle size distribution and zeta potential of the suspended particles in municipal water and lake surface water of Curtin Sarawak's lake were compared and the samples were analysed using dynamic light scattering method. High concentration of suspended particles affects the water quality as well as suppresses the aquatic photosynthetic systems. A new approach has been carried out in the current work to determine the particle size distribution and zeta potential of the suspended particles present in the water samples. The results for the lake samples showed that the particle size ranges from 180nm to 1345nm and the zeta potential values ranges from -8.58 mV to -26.1 mV. High zeta potential value was observed in the surface water samples of Curtin Sarawak's lake compared to the municipal water. The zeta potential values represent that the suspended particles are stable and chances of agglomeration is lower in lake water samples. Moreover, the effects of physico-chemical parameters on zeta potential of the water samples were also discussed.

Monitoring of Water-Level Fluctuation of Lake Nasser Using Altimetry Satellite Data

Science.gov (United States)

El-Shirbeny, Mohammed A.; Abutaleb, Khaled A.

2018-05-01

Apart from the Renaissance Dam and other constructed dams on the River Nile tributaries, Egypt is classified globally as a state of scarce water. Egypt's water resources are very limited and do not contribute a significant amount to its water share except the River Nile (55.5 billion m3/year). While the number of population increases every year, putting more stress on these limited resources. This study aims to use remote-sensing data to assess the change in surface area and water-level variation in Lake Nasser using remote-sensing data from Landsat-8 and altimetry data. In addition, it investigates the use of thermal data from Landsat-8 to calculate water loss based on evaporation from Lake Nasser. The eight Landsat-8 satellite images were used to study the change in surface area of Lake Nasser representing winter (January) and summer (June/July) seasons in two consecutive years (2015 and 2016). Time series analyses for 10-day temporal resolution water-level data from Jason-2/OSTM and Jason-3 altimetry was carried out to investigate water-level trends over the long term (1993 and 2016) and short term (2015-2016) in correspondence with the change of the surface area. Results indicated a shrink in the lake surface area in 2016 of approximately 14% compared to the 2015 area. In addition, the evaporation rate in the lake is very high causing a loss of approximately 20% of the total water share from the river Nile.

Stable isotopes, δ18O and δ2H, in the study of water balance of Lake Massoko, Tanzania: Investigation of the exchange between lake and underground water

International Nuclear Information System (INIS)

Bergonzini, L.; Gibert, E.; Winckel, A.

2002-01-01

Full text: The stable oxygen and deuterium isotope compositions of a lake depend upon its water balance. Therefore the balance equations of stable isotopes, which imply calculation of the composition of evaporating moisture α E , provide information for assessing the water balance. In most cases, this approach is used to investigate the relationships between lakes and groundwater. Lake Massoko (8 deg. 20'S, 33 deg. 45'E, 870 m.a.s.l.) is a freshwater maar-lake without surface outlet. The lake surface and its runoff area cover 0.38 and 0.55 km 2 respectively. In contrast with the mean annual rainfall in the other parts of south Tanzania (1000-1200 mm y -1 ), the presence of Lake Malawi to the South, and the high ranges to the North (Mounts Poroto, Rungwe and Livingstone) imply local climatic features. Air masses overloaded with humidity bypassing Lake Malawi are submitted, especially in April, to ascending currents, producing rainfalls up to 2450 mm y -1 over Massoko area. Because of the evaporation rate from the lake's surface (around 2100 mm y -1 ) and without taking into account the runoff from the drainage basin, hydrological balance is positive and imply underground lost. One of most difficult points in the establishment of the isotope balances is the calculation of the composition of the evaporated water (δ E ), which requires an estimation of the isotopic composition of the water vapour in the atmosphere over the lake (δ Atm ). Without direct measurements, two ways can be used for the determination of the vapour composition (i) equilibrium with precipitation and reconstitution from them, or (ii) calculation from the balances of a terminal lake of the region. Both approaches are presented and compared, but only the second one allows physical solutions. δ Atm determined from Lake Rukwa hydrological and isotope balances has been used to calculate values for δ E over Lake Massoko. The estimation of δ Atm obtained from Lake Rukwa budgets presents a deuterium

The Potential of Satellite Imagery to Estimate Chlorophyll-a and Water Clarity Data For the Assessment of Lake Water Quality

Science.gov (United States)

Shrift, M.; Weathers, K. C.; Norouzi, H.; Ewing, H. A.

2017-12-01

Lake water quality is declining nationwide and has become a tremendous point of interest. Remote sensing (RS) data have provided the ability to efficiently study oceans and terrestrial systems over space and time. However, fresh water systems, especially small, nutrient poor lakes have only recently been assessed using remote sensing technology. Prior research suggests that there is poor satellite sensitivity to lakes with low chlorophyll a (chl a) values. This study focuses on the potential to utilize Landsat 8 satellite imagery to predict chl a and Secchi disk transparency values from Lake Auburn, Maine, an oligo-mesotrophic lake that is the primary source of drinking water for the cities of Lewiston and Auburn and has had an increasing number of algal blooms. A total of 28 Landsat scenes from 2013-2017 within 4 days of in-lake measurements were collected for band value extraction and radiometric correction. Band combinations were explored and analyzed to obtain the most reliable prediction of in-lake chl a and Secchi disk values. A nonlinear combination of bands 5 and 4 for chl a, and bands 3 and 2 for Secchi disk transparency show the most promising algorithms, with correlations coefficients of 0.57 and 0.74, respectively. The resultant algorithms show promise for utilizing RS data to estimate water quality for a large array of low-nutrient lakes in northern North America, and thereby to gain a better understanding of water quality of our vital fresh water resources.

Groundwater quality in the Indian Wells Valley, California

Science.gov (United States)

Dawson, Barbara J. Milby; Belitz, Kenneth

2012-01-01

Groundwater provides more than 40 percent of California’s drinking water. To protect this vital resource, the State of California created the Groundwater Ambient Monitoring and Assessment (GAMA) Program. The Priority Basin Project of the GAMA Program provides a comprehensive assessment of the State’s groundwater quality and increases public access to groundwater-quality information. Indian Wells Valley is one of the study areas being evaluated. The Indian Wells study area is approximately 600 square miles (1,554 square kilometers) and includes the Indian Wells Valley groundwater basin (California Department of Water Resources, 2003). Indian Wells Valley has an arid climate and is part of the Mojave Desert. Average annual rainfall is about 6 inches (15 centimeters). The study area has internal drainage, with runoff from the surrounding mountains draining towards dry lake beds in the lower parts of the valley. Land use in the study area is approximately 97.0 percent (%) natural, 0.4% agricultural, and 2.6% urban. The primary natural land cover is shrubland. The largest urban area is the city of Ridgecrest (2010 population of 28,000). Groundwater in this basin is used for public and domestic water supply and for irrigation. The main water-bearing units are gravel, sand, silt, and clay derived from the Sierra Nevada to the west and from the other surrounding mountains. Recharge to the groundwater system is primarily runoff from the Sierra Nevada and to the west and from the other surrounding mountains. Recharge to the groundwater system is primarily runoff from the Sierra Nevada and direct infiltration from irrigation and septic systems. The primary sources of discharge are pumping wells and evapotranspiration near the dry lakebeds. The primary aquifers in the Indian Wells study area are defined as those parts of the aquifers corresponding to the perforated intervals of wells listed in the California Department of Public Health database. Public-supply wells in

Coastal Water Quality Modeling in Tidal Lake: Revisited with Groundwater Intrusion

Science.gov (United States)

Kim, C.

2016-12-01

A new method for predicting the temporal and spatial variation of water quality, with accounting for a groundwater effect, has been proposed and applied to a water body partially connected to macro-tidal coastal waters in Korea. The method consists of direct measurement of environmental parameters, and it indirectly incorporates a nutrients budget analysis to estimate the submarine groundwater fluxes. Three-dimensional numerical modeling of water quality has been used with the directly collected data and the indirectly estimated groundwater fluxes. The applied area is Saemangeum tidal lake that is enclosed by 33km-long sea dyke with tidal openings at two water gates. Many investigations of groundwater impact reveal that 10 50% of nutrient loading in coastal waters comes from submarine groundwater, particularly in the macro-tidal flat, as in the west coast of Korea. Long-term monitoring of coastal water quality signals the possibility of groundwater influence on salinity reversal and on the excess mass outbalancing the normal budget in Saemangeum tidal lake. In the present study, we analyze the observed data to examine the influence of submarine groundwater, and then a box model is demonstrated for quantifying the influx and efflux. A three-dimensional numerical model has been applied to reproduce the process of groundwater dispersal and its effect on the water quality of Saemangeum tidal lake. The results show that groundwater influx during the summer monsoon then contributes significantly, 20% more than during dry season, to water quality in the tidal lake.

Regional distribution and relevance in paleonvironmental studies of lakes in the Tatra Mts. (Western Carpathians

Directory of Open Access Journals (Sweden)

Joanna POCIASK-KARTECZKA

2014-11-01

Full Text Available Scientific limnological research in the Tatra Mountains were initiated by Stanislaw Staszic in the early XIX century.  After the World War II, the evolution of Tatra lakes was investigated by Kondracki, Klimaszewski, Baumgart-Kotarba and. Extensive paleolimnological investigations in the Tatra Mountains were started by the group of scientists led by K. Starmach in the beginning of the second half of the 20th century. There has been not much research concerned to the regional distribution of lakes and their properties in the Tatra Mountains (Pociask-Karteczka 2013. Very early division of lakes presented A. Gadomski (1922, which distinguished four types of lakes: a tarns (cirque lake or corrie loch, b bedrock-dammed lakes, c moraine lakes. This division was concerned in subsequent publications (Choiński 2007. M. Lukniš (1973, 1985 recognized additional types: kettles and landslide-dammed lakes and M. Klimaszewski (1988 – inter-sheepback lakes. J. Pacl and K. Wit-Jóźwik in Klima Tatier (Pacl, Wit-Jóźwik 1974 were focused on the temperature of water in lakes in Polish and Slovak parts and M. Borowiak (2000a,b provided a comprehensive analysis of types, dimensions, temperature and chemical composition of water in lakes in the Tatra Mountains.According to present day state of knowledge, one may distinguish following genetic types of lakes: I glacial, II not-glacial. There are four types of the glacial origin lakes in the Tatra Mountains (Fig. 1: a tarns (cirque lakes or corrie loch, b bedrock-moraine dammed lakes, c inter-sheepback lakes, d moraine lakes, e kettles.Most of lakes in the Tatra Mountains are tarns and bedrock-moraine dammed lakes, and they are located at the elevation over 1400 m a.s.l. in the Western Tatra Mountains, and over 1600 m a.s.l. in the High Tatra Mountains. Some of them are paternoster lakes – a series of stair-stepped lakes formed in individual rock basins aligned down the course of a glaciated valley. Lakes in