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At least 235 records · Page 13Linked to original sources

Surface water of Little River basin in southeastern Oklahoma (with a section on quality of water by R. P. Orth)

This report summarizes basic hydrologic data of the surface water resources of Little River basin above the Oklahoma-Arkansas state line near Cerrogordo, Okla., and by analysis and interpretation, presents certain streamflow characteristics at specified points in the basin. Little River basin above the state line includes 2,269 square miles, of which about 250 square miles of the Mountain Fork River is in Arkansas. The climate is humid and the annual precipitation averages about 46 inches. Gross annual lake evaporation averages 49 inches per year. There are three reservoirs totaling 2,831,800 acre-feet of storage, either authorized or under construction in the basin. The average annual discharge at the gaging stations for the period 1930-61 is 674,900 acre-feet for Little River near Wright City; 1,273,000 acre-feet for Little River below Lukfata Creek, near Idabel; and 989,000 acre-feet for Mountain Fork River near Eagletown. The average annual discharge of Little River at the Oklahoma-Arkansas state line near Cerrogordo is 2,401,000 acre-feet. Flow-duration curves have been developed from daily records for the gaging stations. These curves show the percentage of time various rates of discharge have been equaled or exceeded. Procedures for defining the frequency of annual floods at any point in the basin are given. Low-flow frequency curves for the gaging stations defining the recurrence intervals of 7, 14 or 15, 30, 60, and 120 day mean flows have been prepared. Curves showing the relation of instantaneous discharge at specified upstream points to the daily mean discharge at two gaging stations are presented. The storage requirements for suplementing natural flows have been prepared for the gaging-station sites. Chemical analyses show that the surface water in the basin is suitable for domestic and industrial uses.

Open-File Report↗

Characterization and simulation of ground-water flow in the Kansas River Valley at Fort Riley, Kansas, 1990-98

Hydrologic data and a ground-water flow model were used to characterize ground-water flow in the Kansas River alluvial aquifer at Fort Riley in northeast Kansas. The ground-water flow model was developed as a tool to project ground-water flow and potential contaminant-transport paths in the alluvial aquifer on the basis of past hydrologic conditions. The model also was used to estimate historical and hypothetical ground-water flow paths with respect to a private- and several public-supply wells. The ground-water flow model area extends from the Smoky Hill and Republican Rivers downstream to about 2.5 miles downstream from the city of Ogden. The Kansas River Valley has low relief and, except for the area within the Fort Riley Military Reservation, is used primarily for crop production. Sedimentary deposits in the Kansas River Valley, formed after the ancestral Kansas River eroded into bedrock, primarily are alluvial sediment deposited by the river during Quaternary time. The alluvial sediment consists of as much as about 75 feet of poorly sorted, coarse-to-fine sand, silt, and clay, 55 feet of which can be saturated with ground water. The alluvial aquifer is unconfined and is bounded on the sides and bottom by Permian-age shale and limestone bedrock. Hydrologic data indicate that ground water in the Kansas River Valley generally flows in a downstream direction, but flow direction can be quite variable near the Kansas River due to changes in river stage. Ground-water-level changes caused by infiltration of precipitation are difficult to detect because they are masked by larger changes caused by fluctuation in Kansas River stage. Ratios of strontium isotopes Sr87 and Sr86 in water collected from wells in the Camp Funston Area indicate that the ground water along the northern valley wall originates, in part, from upland areas north of the river valley. Water from Threemile Creek, which flows out of the uplands north of the river valley, had Sr87:Sr86 ratios similar to those in ground water from wells in the northern Camp Funston Area. In addition, comparison of observed water levels from wells CF90-06, CF97-101, and CF97-401 in the Camp Funston Area and ground-water levels simulated for these wells using floodwave-response analysis indicates that ground-water inflow from bedrock is a hydraulic stress that, in addition to the changing stage in the Kansas River, acts on the aquifer. This hydraulic stress seems to be located near the northern valley wall because the effect of this stress is greater for well CF97-101, which is the well closest to the valley wall. Ground-water flow was simulated using a modular, three-dimensional, finite-difference ground-water flow model (MODFLOW). Particle tracking, used to visualize ground-water flow paths in the alluvial aquifer, was accomplished using MODPATH. Forward-in-time particle tracking indicated that, in general, particles released near the Kansas River followed much more variable paths than particles released near the valley wall. Although particle tracking does not simulate solute transport, this increased path variability indicates that, near the river, ground-water contaminants could follow many possible paths towards the river, whereas more distant from the river, ground-water contaminants likely would follow a narrower corridor. Particle tracks in the Camp Funston Area indicate that, for the 1990-98 simulation period, contaminants from the ground-water study sites in the Camp Funston Area would be unlikely to move into the vicinity of Ogden's supply wells. Backward-in-time particle tracking indicated that the flow-path and recharge areas for model cells corresponding to Ogden's supply wells lie near the northern valley wall and extend into the northern Camp Funston Area. The flow-path and recharge areas for model cells corresponding to Morris County Rural Water District wells lie within Clarks Creek Valley and probably extend outside the model area. Three hypothetical simulations, i

Water-Resources Investigations Report↗

Triangle Area Water Supply Monitoring Project, North Carolina—Overview of hydrologic and water-quality monitoring activities and data quality assurance

Surface-water supplies are important sources of drinking water for residents in the Triangle area of North Carolina, which is located within the upper Cape Fear and Neuse River Basins. Since 1988, the U.S. Geological Survey and a consortium of local governments have participated in a cooperative effort, known as the Triangle Area Water Supply Monitoring Project, to track water-quality and quantity conditions in several of the area’s water-supply reservoirs and streams. This report summarizes the hydrologic and water-quality monitoring activities through this cooperative effort, including an overview of previous and current data collection and quality-assurance and quality-control activities.

North Carolina↗

Water budget and estimated suspended-sediment inflow for Reelfoot Lake, Obion and Lake Counties, Northwestern Tennessee, May 1984-April 1985

Reelfoot Lake in northwestern Tennessee, with a surface area of 15,500 acres at normal pool elevation, is the largest natural lake in Tennessee. Over the years, the lake has become an important economic, environmental, and recreational resource to the people in the area, and to the State of Tennessee. The natural eutrophic succession rate of the lake has apparently been accelerated by land use practices within the Reelfoot Lake drainage basin during the past several decades. The potential loss of Reelfoot Lake has prompted the State to make management and restoration of the lake and its resources a priority objective. The U.S. Geological Survey entered into a cooperative study in May 1984 with the Tennessee Wildlife Resources Agency and the Tennessee Department of Health and Environment, Division of Water Management, to collect and analyze hydrologic data and prepare an annual water budget for Reelfoot Lake. The purpose of the water budget is to provide an analysis of the surface-groundwater-lake-atmospheric water relation at Reelfoot Lake. Results of the analysis can be used by lake managers to evaluate the potential effects of proposed lake management strategies upon the lake and surrounding hydrologic system. The water budget for the 12-month study period (May 1, 1984 through April 30, 1985) is presented in this report. In addition, estimates of suspended-sediment discharge from tributary streams in the Reelfoot Lake basin and an analysis of concentrations of constituents in stream-bottom material at three inflow sites are also presented. (Lantz-PTT)

Tennessee↗

Hydrologic and geochemical approaches for determining ground-water flow components

Lyman Lake is an irrigation-storage reservoir on the Little Colorado River near St. Johns, Arizona. The main sources of water for the lake are streamflow in the Little Colorado River and ground-water inflow from the underlying Coconino aquifer. Two approaches, a hydrologic analysis and a geochemical analysis, were used to compute the quantity of ground-water flow to and from Lyman Lake. Hydrologic data used to calculate a water budget were precipitation on the lake, evaporation from the lake, transpiration from dense vegetation, seepage through the dam, streamflow in and out of the lake, and changes in lake storage. Geochemical data used to calculate the ground-water flow components were major ions, trace elements, and the stable isotopes of hydrogen and oxygen. During the study, the potentiometric level of the Coconino aquifer was above the lake level at the upstream end of the lake and below the lake level at the downstream end. Hydrologic and geochemical data indicate that about 10 percent and 8 percent, respectively, of the water in the lake is ground-water inflow and that about 35 percent of the water in the Little Colorado River 6 miles downgradient from the lake near Salado Springs is ground water. These independent estimates of ground-water flow derived from each approach are in agreement and support a conceptual model of the water budget.

Conference Paper↗

Propagation and composition of the flood wave on the upper Mississippi River, 1993

During spring and summer 1993, record flooding inundated much of the upper Mississippi River Basin. The magnitude of the damages-in terms of property, disrupted business, and personal trauma was unmatched by any other flood disaster in United States history. Property damage alone is expected to exceed $10 billion. Damaged highways and submerged roads disrupted overland transportation throughout the flooded region. The Mississippi and the Missouri Rivers were closed to navigation before, during, and after the flooding. Millions of acres of productive farmland remained under water for weeks during the growing season. Rills and gullies in many tilled fields are the result of the severe erosion that occurred throughout the Midwestern United States farmbelt. The hydrologic effects of extended rainfall throughout the upper Midwestern United States were severe and widespread. The banks and channels of many rivers were severely eroded, and sediment was deposited over large areas of the basin's flood plain. Record flows submerged many areas that had not been affected by previous floods. Industrial and agricultural areas were inundated, which caused concern about the transport and fate of industrial chemicals, sewage effluent, and agricultural chemicals in the floodwaters. The extent and duration of the flooding caused numerous levees to fail. One failed levee on the Raccoon River in Des Moines, Iowa, led to flooding of the city's water treatment plant. As a result, the city was without drinking water for 19 days. As the Nation's principal water-science agency, the U.S. Geological Survey (USGS) is in a unique position to provide an immediate assessment of some of the hydrological effects of the 1993 flood. The USGS maintains a hydrologic data network and conducts extensive water-resources investigations nationwide. Long-term data from this network and information on local and regional hydrology provide the basis for identifying and documenting the effects of the flooding . During the flood, the USGS provided continuous streamflow and related information to the National Weather Service (NWS), the U.S. Army Corps of Engineers, the Federal Emergency Management Agency (FEMA), and many State and local agencies as part of its role to provide basic information on the Nation's surface- and ground-water resources at thousands of locations across the United States. The NWS has used the data in forecasting floods and issuing flood warnings. The data have been used by the Corps of Engineers to operate water diversions, dams, locks, and levees. The FEMA and many State and local emergency management agencies have used USGS hydrologic data and NWS forecasts as part of the basis of their local flood-response activities. In addition, USGS hydrologists are conducting a series of investigations to document the effects of the flooding and to improve understanding of the related processes. The major initial findings from these studies will be reported in this Circular series as results become available. U.S. Geological Survey Circular 1120, Floods in the Upper Mississippi River Basin, 1993, consists of individually published chapters that will document the effects of the 1993 flooding. The series includes data and findings on the magnitude and frequency of peak discharges; precipitation; water-quality characteristics, including nutrients and man-made contaminants; transport of sediment; assessment of sediment deposited on flood plains; effects of inundation on ground-water quality; flood-discharge volume; effects of reservoir storage on flood peaks; stream-channel scour at selected bridges; extent of floodplain inundation; and documentation of geomorphologic changes.

upper Mississippi River basin↗

Methodology for applying monitored natural attenuation to petroleum hydrocarbon-contaminated ground-water systems with examples from South Carolina

Natural attenuation processes such as dispersion, advection, and biogradation serve to decrease concentrations of disssolved contaminants as they are transported in all ground-water systems. However, the efficiency of these natural attenuation processes and the degree to which they help attain remediation goals, varies considerably from site to site. This report provides a methodology for quantifying various natural attenuation mechanisms. This methodology incorporates information on (1) concentrations of contaminants in space and/or time; (2) ambient reduction/oxidation (redox) conditions; (3) rates and directions of ground-water flow; (4) rates of contaminant biodegradation; and (5) demographic considerations, such as the presence of nearby receptor exposure points or property boundaries. This document outlines the hydrologic, geochemical, and biologic data needed to assess the efficiency of natural attenuation, provides a screening tool for making preliminary assessments, and provides examples of how to determine when natural attenuation can be a useful component of site remediation at leaking underground storage tank sites. At a site in the Piedmont Physiographic Province (Laurens, South Carolina), hydrologic and water-chemistry data indicate that the natural attenuation capacity for benzene is approximately 5 percent per foot of flowpath. As a result, benzene concentrations would decrease from about 28,000 micrograms per liter in ground water at the source area to less than 5 micrograms per liter 200 feet downgradient and prior to discharging to a stream. Because of this rapid attenuation, contaminants do not presently impact the stream downgradient of the site. In contrast, at a site in the coastal Plain Physiographic Province (Charleston, South Carolina), hydrologic and water-chemistry data indicate that, even thought the site has a substantial natural attenuation capacity, it may not be sufficient to fully protect a nearby point of ground-water discharge. These two sites illustrate how the efficiency of natural attenuation processes acting on petroleum hydrocarbons can be systematically evaluated using hydrologic, geochemical, and microbiologic methods. These methods, in turn, can be used to assess the role that the natural attenuation of petroleum hydrocarbons can play in achieving overall site remediation.

South Carolina↗

Contributions of nitrogen to the Barnegat Bay-Little Egg Harbor Estuary: Updated loading estimates

Based on the most recent and most accurate data available through 2008, the total load of nitrogen to the Barnegat Bay‐Little Egg Harbor (BB‐LEH) estuary from the most substantial sources (surface water, including surface‐water discharge and direct storm runoff; ground‐water discharge; and atmospheric deposition) is estimated to be 650,000 kilograms of nitrogen per year (kg N/yr). Surface water contributes 66 percent (431,000 kg N/yr), direct ground‐ water discharge accounts for 12 percent (78,000 kg N/yr), and atmospheric deposition accounts for 22 percent (141,000 kg N/yr). This new loading estimate was compared to a previously published estimate produced by using similar methodology but less current data through 1997. Findings of the present study include a substantially lower estimate of atmospheric deposition of nitrogen to the estuary compared to the previous estimate. The study results also offer further support of the relation between land use and nitrogen levels, and indicate that the Toms and Metedeconk River basins account for more than 60 percent of the nitrogen load to the estuary from surface‐water discharge. Differences between the two estimates can be attributed to both the use of more accurate and more recent data in the revised estimate, and actual changes in the magnitude of nitrogen loads from various sources. Gaps in available water‐quality and hydrologic data are documented, and additional analysis and monitoring that may improve the reliability of future nitrogen loading estimates are presented.

New Jersey↗

Hydrogeologic characterization of Area B, Fort Detrick, Maryland

Groundwater in the karst groundwater system at Area B of Fort Detrick in Frederick County, Maryland, is contaminated with chlorinated solvents from the past disposal of laboratory wastes. In cooperation with U.S. Army Environmental Command and U.S. Army Garrison Fort Detrick, the U.S. Geological Survey performed a 3-year study to refine the conceptual model of groundwater flow in and around Area B of Fort Detrick at the site- to regional-scale. The investigation was designed to review the geologic setting, assess the temporal variability of the hydrologic system, evaluate the potential for interbasin groundwater flow, determine the degree of vertical connectivity of the aquifer, characterize the sources and timing of groundwater recharge, and identify if dyes from previous tracer tests continue to drain from the aquifer. This study established a continuous hydrologic monitoring network of 12 water level gages, 2 streamgages, a precipitation gage, and in situ fluorometric monitoring. A water budget analysis was performed using hydrologic monitoring data and a soil-water balance model constructed for the study. In this study each individual water budget term is calculated using available data or through modeling, and a water budget residual term is calculated. If the water budget residual term is small relative to the uncertainty of the underlying data, then an additional import or export of water (in other words, interbasin transfer) is not needed to fully describe the hydrologic system. Groundwater and spring samples from 20 locations were collected in a 2019 synoptic geochemical sampling event and analyzed for a suite of analytes that included groundwater age tracer constituents. The karst groundwater system was found to be highly responsive to hydrologic events, with strong water level and stream base flow responses to individual storm events and a historic wet period in 2017 and 2018. The water budget analysis included historic flooding in May 2018, though more typical hydrologic patterns were observed in 2019 and 2020. During most evaluated intervals, the water budget residual was less than the estimated uncertainty on the residual for the two Carroll Creek watersheds, which suggested no substantial net interbasin flow occurs from these watersheds. The watershed difference area, a region that includes Area B, had a significant negative water budget residual, which may be the result of a net interbasin import of groundwater or the result of focused groundwater recharge not simulated by the soil-water balance model. Geochemical analysis and groundwater age dating reveals shallow groundwater (approximately less than [<] 150 feet deep) appears to be relatively young (approximately <30 years) and to be recharged in the vicinity of Area B. In the deep groundwater sampled in this study (approximately greater than [>] 150 feet deep), older groundwater from a differing recharge source, based on stable isotopes and noble gas analyses, is observed and interpreted to represent less direct connectivity to the surface and increased proportions of water recharged to the north and (or) west of Area B. A clustering analysis to reveal groupings within the suite of geochemical data was used to define seven groups. The groupings generally show that wells in similar depths and lateral aquifer positions generally cluster together, with some exceptions. Although limited by suspended sediments, the in situ fluorometric monitoring at springs did not detect any dye leaving the system above the limit of detection for the method. Dye was only detected above the limit of detection in one well, which was used as an injection well during a previous dye tracer test. The results of this study support and refine the conceptual site model of groundwater hydrology at Area B. The geologic and geophysical log review in this study agrees with prior assessments of physical controls on groundwater flow. A literature review of mid-Atlantic karst studies identified similar controls reported in these environments. The additional characterization of hydrologic responsiveness in this study suggests that hydrologic conditions and events are important considerations when interpreting potentiometric surfaces and contaminant trends over time and highlights the importance of continuous hydrologic monitoring. There is evidence to suggest that either intense focused groundwater recharge occurs in the vicinity of Area B or net along-valley groundwater interbasin flow from the upper study watershed enters the lower watershed and discharges to Carroll Creek. Geochemical analyses also suggest that water recharged from Catoctin Mountain and the elevated areas to the north and (or) west of the site may be present in the older and deeper Area B groundwater.

Maryland↗

Water quality of hydrologic bench marks; an indicator of water quality in the natural environment

Water-quality data, collected at 57 hydrologic bench-mark stations in 37 States, allow the definition of water quality in the 'natural' environment and the comparison of 'natural' water quality with water quality of major streams draining similar water-resources regions. Results indicate that water quality in the 'natural' environment is generally very good. Streams draining hydrologic bench-mark basins generally contain low concentrations of dissolved constituents. Water collected at the hydrologic bench-mark stations was analyzed for the following minor metals: arsenic, barium, cadmium, hexavalent chromium, cobalt, copper, lead, mercury, selenium, silver, and zinc. Of 642 analyses, about 65 percent of the observed concentrations were zero. Only three samples contained metals in excess of U.S. Public Health Service recommended drinking-water standards--two selenium concentrations and one cadmium concentration. A total of 213 samples were analyzed for 11 pesticidal compounds. Widespread but very low-level occurrence of pesticide residues in the 'natural' environment was found--about 30 percent of all samples contained low-level concentrations of pesticidal compounds. The DDT family of pesticides occurred most commonly, accounting for 75 percent of the detected occurrences. The highest observed concentration of DDT was 0.06 microgram per litre, well below the recommended maximum permissible in drinking water. Nitrate concentrations in the 'natural' environment generally varied from 0.2 to 0.5 milligram per litre. The average concentration of nitrate in many major streams is as much as 10 times greater. The relationship between dissolved-solids concentration and discharge per unit area in the 'natural' environment for the various physical divisions in the United States has been shown to be an applicable tool for approximating 'natural' water quality. The relationship between dissolved-solids concentration and discharge per unit area is applicable in all the physical divisions of the United States, except the Central Lowland province of the Interior Plains, the Great Plains province of the Interior Plains, and the Basin and Ridge province of the Intermontane Plateaus. The relationship between dissolved-solids concentration and discharge per unit area is least variable in the New England province and Blue Ridge province of the Appalachian Highlands. The dissolved-solids concentration versus discharge per unit area in the Central Lowland province of the Interior Plains is highly variable. A sample collected from the hydrologic bench-mark station at Bear Den Creek near Mandaree, N. Dak., contained 3,420 milligrams per litre dissolved solids. This high concentration in the 'natural' environment indicates that natural processes can be principal agents in modifying the environment and can cause degradation. Average annual runoff and rock type can be used as predictive tools to determine the maximum dissolved-solids concentration expected in the 'natural' environment.

Circular↗

Hydrologic data for the Walker River Basin, Nevada and California, water years 2010–14

Walker Lake is a threatened and federally protected desert terminal lake in western Nevada. To help protect the desert terminal lake and the surrounding watershed, the Bureau of Reclamation and U.S. Geological Survey have been studying the hydrology of the Walker River Basin in Nevada and California since 2004. Hydrologic data collected for this study during water years 2010 through 2014 included groundwater levels, surface-water discharge, water chemistry, and meteorological data. Groundwater levels were measured in wells, and surface-water discharge was measured in streams, canals, and ditches. Water samples for chemical analyses were collected from wells, streams, springs, and Walker Lake. Chemical analyses included determining physical properties; the concentrations of major ions, nutrients, trace metals, dissolved gases, and radionuclides; and ratios of the stable isotopes of hydrogen and oxygen. Walker Lake water properties and meteorological parameters were monitored from a floating platform on the lake. Data collection methods followed established U.S. Geological Survey guidelines, and all data are stored in the National Water Information System database. All of the data are presented in this report and accessible on the internet, except multiple-depth Walker Lake water-chemistry data, which are available only in this report.

California, Nevada↗

Hydrogeologic data from a test well in east-central Duval County, Florida

A 2,112-foot test well was drilled in east-central Duval County, Florida, to obtain geologic, hydrologic, and water chemistry data. Drill cuttings and water samples were collected, and water-level measurements and lithologic and geophysical logs were made. Deposits to a depth of 575 feet consist of sand, clayey sand, phosphatic sandy clay, coquina, sandy limestone, and dolostone. Below 575 feet, the deposits consist of fragmented and granular limestone, dolomitic limestone, and massive to finely crystalline dolostone, which comprise the Floridan aquifer system in the area. Water levels were measured near or at the bottom of the drill hole through the drill stem and in the annular space between the drilled hole and drill stem at the well head as drilling progressed from 770 to 2,112 feet in depth. Water levels measured through the drill stem ranged from 1.17 feet above land surface at a depth of 2,107 feet to 15.0 feet above land surface at a depth of 1,574 feet. Water levels measured in the annular space ranged from 7.5 feet above land surface at a depth of 770 feet to 14.9 feet at various depths from 1,574 to 1,721 feet. Chloride concentrations of water sampled through the drill stem from a depth of 711 to 1 ,616 feet ranged from 22 to 150 milligrams per liter at 1,648 feet. Chloride concentrations then ranged from 345 to about 800 milligrams per liter to a depth of 2,071 feet and then increased to a maximum of 5,450 milligrams per liter at 2,107 feet. (USGS)

Open-File Report↗

Normal streamflows and water levels continue—Summary of hydrologic conditions in Georgia, 2014

The U.S. Geological Survey (USGS) South Atlantic Water Science Center (SAWSC) Georgia office, in cooperation with local, State, and other Federal agencies, maintains a long-term hydrologic monitoring network of more than 350 real-time, continuous-record, streamflow-gaging stations (streamgages). The network includes 14 real-time lake-level monitoring stations, 72 real-time surface-water-quality monitors, and several water-quality sampling programs. Additionally, the SAWSC Georgia office operates more than 204 groundwater monitoring wells, 39 of which are real-time. The wide-ranging coverage of streamflow, reservoir, and groundwater monitoring sites allows for a comprehensive view of hydrologic conditions across the State. One of the many benefits this monitoring network provides is a spatially distributed overview of the hydrologic conditions of creeks, rivers, reservoirs, and aquifers in Georgia. Streamflow and groundwater data are verified throughout the year by USGS hydrographers and made available to water-resource managers, recreationists, and Federal, State, and local agencies. Hydrologic conditions are determined by comparing the statistical analyses of data collected during the current water year to historical data. Changing hydrologic conditions underscore the need for accurate, timely data to allow informed decisions about the management and conservation of Georgia’s water resources for agricultural, recreational, ecological, and water-supply needs and in protecting life and property.

Georgia↗

Long-range plans for hydrologic investigations in New Mexico

Objectives of the hydrologic-data-collection projects presented in this report include continuing to identify future data needs; conducting an analysis of the water-quality, ground-water, and surface-water observation networks; and entering all available current and historical hydrologic data into the U.S. Geological Survey Water Data Storage and Retrieval System (WATSTORE). Objectives of areal-appraisal studies include evaluating the water resources in the Gallup-Grants-Zuni-Acoma Sag area and on the eastern flank of the Sandi and Manzano Mountains in Bernalillo County. Potential projects for basin assessments include quantifying the ground-water/surface-water relationships on rivers with flows governed by compacts and an investigation of the water resources of the Estancia Basin. Projects that will assist in the evaluation of energy-related activities include describing the effects of resaturation of coal mines and of milling operations on the quality and quantity of ground and surface water. Activities that need to be undertaken to assist in addressing waste-disposal problems include the evaluation of the hydrologic factors influencing the feasibility of cleanup at the Albuquerque South Valley ' superfund ' site and the establishment of a monitoring network at the Waste Isolation Pilot Plant project near Carlsbad. Scientific methods that need to be developed include (1) the testing of analytical techniques for estimating site-specific conditions with the results of digital hydrologic models, and (2) the determination of the influence of recharge from ephemeral streams on alluvial aquifers. (USGS)

Open-File Report↗

Monograph for using paleoflood data in Water Resources Applications

The Environmental and Water Resources Institute (EWRI) Technical Committee on Surface Water Hydrology is sponsoring a Task Committee on Paleoflood Hydrology to prepare a monograph entitled, "Use of Paleoflood and Historical Data in Water Resources Applications." This paper introduces the subject of paleoflood hydrology and discusses the topics, which are expected to be included in the monograph. The procedure for preparing and reviewing the monograph will also be discussed. The paleoflood hydrology monograph will include a discussion of types of hydrologic and paleoflood data, paleostage indicators, flood chronology, modeling methods, interpretation issues, water resources applications and case studies, and research needs. Paleoflood data collection and analysis techniques will be presented, and various applications in water-resources investigations will be provided. An overview of several flood frequency analysis approaches, which consider historical and paleoflood data along with systematic streamflow records, will be presented. The monograph is scheduled for completion and publication in 2001. Copyright ASCE 2004.

Conference Paper↗

Water-quality and hydrologic conditions at a site of ground-water contamination by volatile organic compounds, South Grafton, Massachusetts, September and October 1994

Ground-water quality and hydrologic data were collected at a site contaminated by volatile organic compounds (VOCs) in South Grafton, Massachusetts, during September and October 1994. The VOCs have formed a plume of contaminated ground water at an abandoned textile mill adjacent to the Blackstone River. Concentrations of total VOCs in the plume ranged from less than 1 to more than 40,000 micrograms per liter. Trichloroethylene (TCE) was the primary chlorinated contaminant, comprising as much as 98 percent of the total VOCs. The highest concentration, 43,000 micrograms per liter, was higher than any previously measured concentration at the site; however, the maximum extent and distribution of concentrations in the VOC plume in September 1994 was similar to that found in July 1993 and in earlier rounds of sampling. In addition to TCE, 1,2-dichloroethene (1,2-DCE) and vinyl chloride were detected at most sites. Spatial and temporal changes in concentrations of TCE, 1,2-DCE, and vinyl chloride are consistent with the hypothesis that TCE biodegradation was the source of 1,2-DCE and vinyl chloride. Ground water at the site contained low to moderately high concentrations of dissolved solids (44 to 406 milligrams per liter), had a moderately high specific conductance (155 to 670 microsiemens per centimeter at 25 degrees Celsius), and was slightly acidic (pH=5.9 to 7.0). Concentrations of the major ions-calcium, sodium, chloride, and sulfate-were not related to VOC concentrations. Dissolved-oxygen concentrations were low (0 to 2 milligrams per liter) throughout most of the aquifer. Distribution of nitrogen species, iron, and manganese indicates that zones of varying oxidation-reduction potential were present in the aquifer. Concentrations of trace metals other than iron or manganese, including arsenic, cadmium, chromium, and copper, generally were less than analytical detection limits. Stream stage in the Blackstone River at the site during September and October 1994 fluctuated by about 1 to 2 feet within 24-hour periods. These rapid fluctuations resulted from sudden release of impounded water at a hydroelectric-generating facility downstream from the site. In addition to the daily fluctuations, rapid small changes in stream stage also occurred that were related to storms. Fluctuations in ground-water levels in four observation wells at the site were similar in amplitude and timing to the rapid fluctuations in stream stage; the daily fluctuations of ground-water levels were greatest in an observation well within 100 feet of the river and least in an observation well about 300 feet from the river. Because ground- water levels at the study site seem to be affected by fluctuations in stage of the Blackstone River, transport of the VOC plume in ground water also is likely to be affected by the fluctuations in stage.

Open-File Report↗

Seasonal periphyton response to low-level nutrient exposure in a least disturbed mountain stream, the Buffalo River, Arkansas

Like most streams located in the Ozark Plateaus, the Buffalo River in Arkansas generally has excellent water quality. Water-quality conditions in Big Creek, however, a major tributary of the middle Buffalo River, have been less favorable than that of other Buffalo River tributaries. Concerns regarding the influence of water quality in Big Creek on the Buffalo River magnified in 2013 when a large confined animal feeding operation (CAFO) began operating in the watershed. In response to these concerns, the U.S. Geological Survey compared monthly nutrient concentrations and seasonal periphyton assemblage metrics of a site on Big Creek downstream of the CAFO, two Buffalo River control sites upstream of the confluence with Big Creek, and three Buffalo River test sites downstream of the confluence with Big Creek. In addition to identifying potential nutrient patterns and periphyton responses along a low-level nutrient exposure gradient, the study determined how nutrient contributions from Big Creek (and the CAFO) are affecting ecological conditions and consequent ecosystem services in the Buffalo River. Nutrient and periphyton data exhibited more temporal than spatial variability. Nutrient concentrations were generally highest of all sites at the Big Creek site. Concentrations at the five sites on the Buffalo River were typically low (near laboratory reporting limits), and concentrations at the three test sites rarely exceeded those of the two control sites. An index developed with three ecologically relevant periphyton metrics (oligotrophic taxa and Homoeothrix percent relative abundance and mesotrophic diatoms percent taxa richness) suggested that nutrient uptake at sites downstream of the Big Creek-Buffalo River confluence resulted in subtle shifts in downstream periphyton assemblages. The periphyton index of biological integrity at control sites was slightly and generally more favorable compared to test sites. Even so, when periphyton data were considered in conjunction with both hydrology and water-quality data, the negative consequences of antecedent high flows and associated scouring exceeded the potential positive effects that low-level nutrients had on algal productivity. These findings emphasize the importance of comparing biological and chemical data across extended temporal scales, particularly when working with low-level nutrient gradients.

Arkansas↗

Predevelopment water levels, groundwater recharge, and selected hydrologic properties of aquifer materials, Hinkley and Water Valleys, California

Hydrologic and geophysical data were collected to support updates to an existing groundwater-flow model of Hinkley Valley, California, in the Mojave Desert about 80 miles northeast of Los Angeles, California. These data provide information on predevelopment (pre-1930) water levels, groundwater recharge, and selected hydrologic properties of aquifer materials. A predevelopment groundwater-level map, drawn using water-level measurements from 48 wells collected as early as 1918, showed groundwater movement from recharge areas along the Mojave River to evaporative discharge areas near the margin of Harper (dry) Lake in Water Valley. During predevelopment conditions, depth to water ranged from near land surface along the Mojave River to above land surface near Harper (dry) Lake, consistent with flowing wells in Water Valley at that time. Depths to water in much of Hinkley Valley downgradient from the Lockhart fault were less than 20 feet below land surface. By 2017, water-level declines as a result of agricultural pumping, were as much as 60 feet near the Hinkley compressor station. Areal recharge from infiltration of precipitation on the valley floor is negligible. Average annual recharge as infiltration of runoff from upland drainages to Hinkley and Water Valleys averages 64.7 acre-feet per year. In most years recharge does not occur; in years when it occurs, recharge to Hinkley Valley is typically about 296 acre-feet. In contrast, average recharge as infiltration of streamflow from the Mojave River from 1931 to 2015 was between 13,400 and 17,100 acre-feet per year; in some years recharge from the Mojave River exceeded 100,000 acre-ft. Estimates of predevelopment groundwater movement through Hinkley Gap and groundwater discharge to Harper (dry) Lake ranged from 570 to 1,900 and 820 to 2,460 acre-feet per year, respectively; at the time of this study in 2017, groundwater movement through Hinkley Gap was estimated to be about 83 acre-feet per year. Hydraulic-conductivity values estimated from slug-test data for 95 monitoring wells ranged from less than 0.1 to 680 feet per day (ft/d); values generally decreased with depth. Median hydraulic-conductivity values calculated from nuclear magnetic resonance (NMR) data for Mojave River alluvium and near-shore lake deposits were 73 and 11 ft/d, respectively; median hydraulic-conductivity values for locally derived alluvium and weathered bedrock were 6 and 2 ft/d, respectively. Hydraulic-conductivity values, estimated from NMR data for formerly saturated deposits overlying the 2017 water table, were as high as 300 ft/d near the Hinkley compressor station. Downgradient from the Hinkley compressor station, formerly saturated deposits had hydraulic-conductivity values of about 150 ft/d, which were higher than values in saturated material. Coarse-textured, permeable material in formerly saturated deposits above the 2017 water table may have allowed groundwater, released from the Hinkley compressor station that may have contained Cr(VI), to move rapidly downgradient. The Lockhart fault is an impediment to groundwater flow within Hinkley Valley. Groundwater-flow directions from horizontal point-velocity probe data were deflected to the west on the upgradient side of the fault compared to the nominal direction of groundwater flow estimated from water-level data. Younger groundwater was present on the upgradient and downgradient sides of the fault, and older groundwater with unadjusted carbon-14 ages as old as 5,650 years before present was in water from wells within splays of the Lockhart fault, consistent with limited groundwater movement across the fault. As a result, groundwater and Cr(VI) released from the Hinkley compressor station moved to the northwest along the downgradient side of the fault. Coupled well-bore flow and depth-dependent water-quality data show water from wells C-01 and IW-03 within the Q4 2015 (October–December 2015) regulatory Cr(VI) plume was yielded from thin layers within the aquifer that are composed of well-sorted lake-margin (beach) deposits that likely have high lateral and longitudinal connectivity. Collectively, data show highly permeable deposits above the regional water table and thin permeable deposits within saturated portions of the upper aquifer that may have conducted groundwater and Cr(VI) downgradient when releases from the Hinkley compressor station first occurred.

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