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At least 217 records · Page 12Linked to original sources

Willamette Basin Comprehensive Study of Water and Related Land Resources: Appendix B--Hydrology

The study was undertaken to plan for the proper development of water and related land resources of the Willamette Basin in Oregon. Appendix B , along with Appendices A and C, provides supporting data for the functional Appendices D through L. Climate is first discussed, including the climatic significance of geographical features such as the Pacific Ocean, the Columbia Gorge, and the Coast and Cascade Ranges, climatic elements (e.g. , temperature, precipitation, evaporation), and meteorological aspects of major storms--rain, wind, and snow. A description of water resources , their distribution, and their variation at different times are presented. These resources are described in terms of factors influencing the occurrence of water . Specifically reviewed here are surface waters, groundwater, the relationship between surface and groundwater, management programs, and water rights and legal restrictions. Lastly, the adequacy of hydrologic data is reviewed. Statistical and interpretive hydrologic data necessary for broadscale water resources planning are provided. Data assembled are those concerning climate, streamflow, lakes and glaciers, chemical-quality, sediment, stream temperature, and groundwater. Geologic and soils mapping are briefly discussed, and a list of references is provided.

Report↗

User guide to Exploration and Graphics for RivEr Trends (EGRET) and dataRetrieval: R packages for hydrologic data

Evaluating long-term changes in river conditions (water quality and discharge) is an important use of hydrologic data. To carry out such evaluations, the hydrologist needs tools to facilitate several key steps in the process: acquiring the data records from a variety of sources, structuring it in ways that facilitate the analysis, processing the data with routines that extract information about changes that may be happening, and displaying findings with graphical techniques. A pair of tightly linked R packages, called dataRetrieval and EGRET (Exploration and Graphics for RivEr Trends), have been developed for carrying out each of these steps in an integrated manner. They are designed to easily accept data from three sources: U.S. Geological Survey hydrologic data, U.S. Environmental Protection Agency (EPA) STORET data, and user-supplied flat files. The dataRetrieval package not only serves as a “front end” to the EGRET package, it can also be used to easily download many types of hydrologic data and organize it in ways that facilitate many other hydrologic applications. The EGRET package has components oriented towards the description of long-term changes in streamflow statistics (high flow, average flow, and low flow) as well as changes in water quality. For the water-quality analysis, it uses Weighted Regressions on Time, Discharge and Season (WRTDS) to describe long-term trends in both concentration and flux. EGRET also creates a wide range of graphical presentations of the water-quality data and of the WRTDS results. This report serves as a user guide to these two R packages, providing detailed guidance on installation and use of the software, documentation of the analysis methods used, as well as guidance on some of the kinds of questions and approaches that the software can facilitate.

Techniques and Methods↗

Water resources data, Iowa water year 2004, volume 1: surface water and precipitation

This volume of the annual hydrologic data report of Iowa is one of a series of annual reports that document hydrologic data gathered from the U.S. Geological Survey.s surface- and ground-water data-collection networks in each State, Puerto Rico, and the Trust Territories. These records of streamflow, ground-water levels, and quality of water provide the hydrologic information needed by local, State, and Federal agencies, and the private sector for developing and managing our Nation.s land and water resources. This report is the culmination of a concerted effort by dedicated personnel of the U.S. Geological Survey who collected, compiled, analyzed, verified, and organized the data, and who typed, edited, and assembled the report. The authors had primary responsibility for assuring that the information contained herein is accurate, complete, and adheres to Geological Survey policy and established guidelines.

Iowa↗

Hydrologic data for the Weldon Spring radioactive waste-disposal sites, St. Charles County, Missouri; 1984-1986

Hydrologic and water quality data were collected during an investigation of the Weldon Spring radioactive waste disposal sites and surroundings area in St. Charles County, Missouri, from 1984 to 1986. The data consists of water quality analyses of samples collected from 45 groundwater and 27 surface water sites. This includes analyses of water from four raffinate pits and from the Weldon Spring quarry. Also included in the report are the results of a seepage run on north flowing tributaries to Dardenne Creek from Kraut Run to Crooked Creek. Mean daily discharge from April 1985 to April 1986 is given for two springs located about 1.5 mi north of the chemical plant. (USGS)

Open-File Report↗

Microbial and Nutrient Concentration and Load Data During Stormwater Runoff at a Swine Concentrated Animal Feeding Operation in the North Carolina Coastal Plain, 2006-2007

This report summarizes water-quality and hydrologic data collected during 2006-2007 to characterize bacteria and nutrient loads associated with overland runoff and subsurface tile drainage in spray fields at a swine concentrated animal feeding operation. Four monitoring locations were established at the Lizzie Research Site in the North Carolina Coastal Plain Physiographic Province for collecting discharge and water-quality data during stormwater-runoff events. Water stage was measured continuously at each monitoring location. A stage-discharge relation was developed for each site and was used to compute instantaneous discharge values for collected samples. Water-quality samples were collected for five storm events during 2006-2007 for analysis of nutrients and fecal indicator bacteria. Instantaneous loads of nitrite plus nitrate, total coliform, Escherichia coli (E. coli), and enterococci were computed for selected times during the five storm events.

North Carolina↗

Summary of hydrologic conditions of the Louisville area, Kentucky

Water problems and their solutions have been associated with the growth and development of the Louisville area for more than a century. Many hydrologic data that aided water users in the past can be applied to present water problems and will be helpful for solving many similar problems in the future. Most of the water problems of Louisville, a water-rich area, concern management and are associated with the distribution of supplies, the quality of water, drainage, and waste disposal. The local hydrologic system at Louisville is dominated by the Ohio River and the glacial-outwash deposits beneath its flood plain. The water-bearing limestones in the uplands are ,secondary sources of water. The average flow of the Ohio River at Louisville, 73 billion gallons per day, and the potential availability of 370 million gallons per day of ground water suitable for industrial cooling purposes minimize the chance of acute water shortage in the area. Under current development, use of water averages about 211 million gallons per day, excluding about 392 million gallons of Ohio River water circulated daily through steampower plants and returned directly to the river. Optimum use and control of the water resources will be dependent on solving several water problems. The principal sources of water are in the Ohio River bottom land, whereas the new and potential centers of use are in the uplands. Either water must be piped to these new centers from the present sources or new supplies must be developed. Available data on streamflow and ground water are adequate to plan for the development of small local supplies. Since the completion of floodwalls and levees in 1953, widespread damage from flooding is a thing of the past in the Louisville area. Some local flooding of unprotected areas and of lowlands along tributary streams still takes place. The analyses of streamflow data are useful in planning for protection of these areas, but additional streamflow records and flood-area mapping are needed to best solve the problem. Droughts are a problem only to users of small water supplies in the uplands, where additional water either can be imported or developed locally. Pollution and undesirable chemical quality of water for some uses are the most serious drawbacks to the optimum development of the water resources in Louisville and Jefferson County. Available chemical analyses of ground water are useful for determining its suitability for various uses, but additional data are needed to guide management decisions. Sources of contamination should be inventoried and water samples analyzed periodically to monitor changes in quality.

Kentucky↗

Simulation of runoff and water quality for 1990 and 2008 land-use conditions in the Reedy Creek watershed, east-central Florida

Hydrologic and water-quality data have been collected within the 177-square-mile Reedy Creek, Florida, watershed, beginning as early as 1939, but the data have not been used to evaluate relations among land use, hydrology, and water quality. A model of the Reedy Creek watershed was developed and applied to the period January 1990 to December 1995 to provide a computational foundation for evaluating the effects of future land-use changes on hydrology and water quality in the watershed. The Hydrological Simulation Program-Fortran (HSPF) model was used to simulate hydrology and water quality of runoff for pervious land areas, impervious land areas, and stream reaches. Six land-use types were used to characterize the hydrology and water quality of pervious and impervious land areas in the Reedy Creek watershed: agriculture, rangeland, forest, wetlands, rapid infiltration basins, and urban areas. Hydrologic routing and water-quality reactions were simulated to characterize hydrologic and water-quality processes and the movement of runoff and its constituents through the main stream channels and their tributaries. Because of the complexity of the stream system within the Reedy Creek Improvement District (RCID) (hydraulic structures, retention ponds) and the anticipated difficulty of modeling the system, an approach of calibrating the model parameters for a subset of the gaged watersheds and confirming the usefulness of the parameters by simulating the remainder of the gaged sites was selected for this study. Two sub-watersheds (Whittenhorse Creek and Davenport Creek) were selected for calibration because both have similar land use to watersheds within the RCID (with the exception of urban areas). Given the lack of available rainfall data, the hydrologic calibration of the Whittenhorse Creek and Davenport Creek sub-watersheds was considered acceptable (for monthly data, correlation coefficients, 0.86 and 0.88, and coefficients of model-fit efficiency, 0.72 and 0.74, respectively). The hydrologic model was tested by applying the parameter sets developed for Whittenhorse Creek and Davenport Creek to other land areas within the Reedy Creek watershed, and by comparing the simulated results to observed data sets for Reedy Creek near Vineland, Bonnet Creek near Vineland, and Reedy Creek near Loughman. The hydrologic model confirmation for Reedy Creek near Vineland (correlation coefficient, 0.91, and coefficient of model fit efficiency, 0.78, for monthly flows) was acceptable. Flows for Bonnet Creek near Vineland were substantially under simulated. Consideration of the ground-water contribution to Bonnet Creek could improve the water balance simulation for Bonnet Creek near Vineland. On longer time scales (monthly or over the 72-month simulation period), simulated discharges for Reedy Creek near Loughman agreed well with observed data (correlation coefficient, 0.88). For monthly flows the coefficient of model-fit efficiency was 0.77. On a shorter time scale (less than a month), however, storm volumes were greatly over simulated and low flows (less than 8 cubic feet per second) were greatly under simulated. A primary reason for the poor results at low flows is the diversion of an unknown amount of water from the RCID at the Bonnet Creek near Kissimmee site. Selection of water-quality constituents for simulation was based primarily on the availability of water-quality data. Dissolved oxygen, nitrogen, and phosphorus species were simulated. Representation of nutrient cycling in HSPF also required simulation of biochemical oxygen demand and phytoplankton populations. The correlation coefficient for simulated and observed daily mean dissolved oxygen concentration values at Reedy Creek near Vineland was 0.633. Simulated time series of total phosphorus, phosphate, ammonia nitrogen, and nitrate nitrogen generally agreed well with periodically observed values for the Whittenhorse Creek and Davenport Creek sites. Simulated water-quality constituents at the Bonnet Creek and Reedy Creek near Vineland sites varied as to how well the values agreed with periodically observed constituent concentrations. Simulated water-quality constituent concentrations for the Reedy Creek near Loughman site generally agreed well with observed constituent concentrations. Simulation of a future land-use scenario for the Reedy Creek watershed was based on the hydrologic and water-quality simulations, projected 2008 land use within the RCID, and assuming no change in existing land use for other areas within the Reedy Creek watershed but external to the RCID. The percentages of forest and urban-impervious land use showed the most change between existing and future land use; forest areas decreased by 50 percent and urban-impervious areas increased by 300 percent. Simulated values of mean total phosphorus, phosphate, ammonia nitrogen, and nitrate nitrogen concentrations for existing and future land-use simulations were within 0.01 milligrams per liter of each other. The simulated maximum daily load increased an average of 10 percent for all constituents. Maximum daily nitrate nitrogen load increased about 17 percent, the greatest increase of all daily constituent loads. Duration curves of daily total phosphorus, phosphate, ammonia nitrogen, and nitrate nitrogen load indicated an increase in the likelihood of exceeding a given load throughout the range of daily constituent loads at Reedy Creek near Loughman.

Florida↗

ATLSS high-resolution topography and hydrology model

The Across Trophic Level System Simulation (ATLSS) Program of the U.S. Geological Survey has produced High-Resolution Hydrology and High-Resolution Topography models to provide high-resolution hydrologic data for the Greater Everglades landscape. Such hydrologic data is essential for describing the effect of hydrology on the important wildlife populations that are being modeled by the ATLSS Program. These ATLSS models are used to evaluate the effects of different water regulation plans as part of the Comprehensive Everglades Restoration Plan (CERP). The need for such high-resolution hydrologic data is great. Although many hydrology data sets exist for South Florida, they either provide data at a spatial scale that is too coarse to apply to models of animal populations, or do not cover a large enough spatial area. For example, the hydrology data generated by the South Florida Water Management Model (SFWMM) provides hydrology data at a 2- x 2-mile resolution. Landscape features important to wildlife habitat, however, almost always require a finer scale of spatial resolution to be represented. With data from the SFWMM, individual model organisms only have information about the differences between 2- x 2-mile cells, a scale that is beyond the perceptual range of most organisms.

Fact Sheet↗

Water-quality data for the Santa Clara-Calleguas hydrologic unit, Ventura County, California, October 1989 through December 1993

More than 700 water samples were collected from 232 wells and 34 surface-water sites in the Santa Clara-Calleguas Hydrologic Unit, Ventura County, California, from October 1989 through December 1993 as part of the U.S. Geological Survey's Southern California Regional Aquifer-System Analysis study. Most samples were analyzed for major ions, nutrients, selected trace elements, oxygen-18, and deuterium. Selected samples were analyzed for one or more of the following isotopes: carbon-13/12, carbon-14, strontium-87/86, sulfur-34/32, and tritium. Other samples were analyzed for one or more of the following dissolved gases: hydrogen, methane, oxygen, and freon-11. Location of sampling sites is shown on maps and the results are presented in tables.

Open-File Report↗

The ground-water-level monitoring network in Iowa

The ground-water-level monitoring network in Iowa consists of 202 wells completed in the principal bedrock and surficial aquifers that supply ground water to numerous users throughout the State. The bedrock aquifers include the Cambrian-Ordovician aquifer system, the Silurian-Devonian aquifer, the Mississippian aquifer, localized Pennsylvanian aquifers, and the Dakota aquifer. The surficial aquifers can be divided into three types: (1) buried channel, (2) alluvial, and (3) glacial drift. Information about the location, date of construction, and depth of each well, and the year water-level measurements began are provided for wells completed in each aquifer. The objectives of the ground-water-level monitoring network in Iowa are to provide the data needed to: (1) determine the change in aquifer storage, (2) document the effects of climatic stress and human activities on discharge and recharge to the principal aquifers, (3) quantify the physical characteristics of ground-water flow including the transmissivity, hydraulic conductivity, and specific capacity of aquifers; and (4) provide historical baseline data for future research. The design of the ground-water-level monitoring network in Iowa that satisfies these objectives includes three types of data: (1) hydrologic data, (2) water-management data for use by State and local officials, and (3) baseline data.

Iowa↗

A hydrologic primer for New Jersey watershed management

The U.S. Geological Survey (USGS) and the N.J. Department of Environmental Protection (NJDEP), and many other agencies and organizations are striving to educate the public about New Jersey’s water resources. In 1996, the NJDEP began implementing a “watershed management approach” to maintain the physical, chemical, and biological integrity of New Jersey’s waters. This approach concentrates on managing individual watershed areas by (1) defining the physical geographic boundaries of the watersheds, (2) basing water policy on sound scientific principles, and (3) developing partnerships with the public--the people most affected by watershed-management policies. New Jersey can be divided into five water regions as defined by the NJDEP: the Northeast, Raritan, Northwest, Lower Delaware, and Atlantic Coastal water regions (fig. 1). Each water region has been divided into three to five “watershed-management areas,” each of which encompasses a particular group of major rivers (fig. 2a-e). Each watershed management area consists of many smaller watersheds. Hydrologic data collected by Federal and State government agencies are invaluable as resources to policymakers who make decisions that affect the use of water in a particular watershed. The purpose of this report is to educate water-resource managers, policymakers, government officials, and the public about hydrologic concepts and the water-resource data needed to make informed decisions about water-management issues. (“Hydrologic” means relating to the occurrence, distribution, movement, and chemistry of all waters of the Earth (Fetter, 1980)). The first part of the report describes basic hydrologic concepts and includes explanations of the hydrologic cycle, the water budget, the surfacewater and ground-water flow systems, water-quality concepts and standards, and water use. The second part of the report summarizes the types of waterresource data that are available from Federal and State government agencies. Instructions on how to obtain the data and contact the appropriate Federal and State agencies, as well as suggestions for additional reading, also are included.

New Jersey↗

Water consumption by nuclear powerplants and some hydrological implications

Published data show that estimated water consumption varies with the cooling system adopted, being least in once-through cooling (about 18 cubic feet per second per 1,000 megawatts electrical) and greatest in closed cooling with mechanical draft towers (about 30 cubic feet per second per 1,000 megawatts electrical). When freshwater is used at this magnitude, water-resources economy may be affected in a given region. The critical need for cooling water at all times by the nuclear powerplant industry, coupled with the knowledge that water withdrawal in the basin will generally increase with time and will be at a maximum during low-flow periods, indicates a need for reexamination of the design low flow currently adopted and the methods used to estimate it. The amount of power generated, the name of the cooling water source, and the cooling method adopted for all nuclear powerplants projected to be in operation by 1985 in the United States are tabulated and the estimated annual evaporation at each powerplant site is shown on a map of the conterminous United States. Another map is presented that shows all nuclear powerplants located on river sites as well as stream reaches in the United States where the 7-day, 10-year low flow is at least 300 cubic feet per second or where this amount of flow can be developed with storage. (Woodard-USGS)

Circular↗

Hydrology and cycling of nitrogen and phosphorus in Little Bean Marsh: A remnant riparian wetland along the Missouri River in Platte County, Missouri, 1996–97

The lack of concurrent water-quality and hydrologic data on riparian wetlands in the Midwestern United States has resulted in a lack of knowledge about the water-quality functions that these wetlands provide. Therefore, Little Bean Marsh, a remnant riparian wetland along the Missouri River, was investigated in 1996 and 1997 primarily to determine the magnitude and character of selected water-quality benefits that can be produced in such a wetland and to identify critical processes that can be managed in remnant or restored riparian wetlands for amelioration of water quality. Little Bean Marsh averages 69 hectares in size, has a maximum depth of about 1 meter, and the majority of the marsh is covered by macrophytes. In 1997, 41 percent of the water received by Little Bean Marsh was from direct precipitation, 14 percent was from ground-water seepage, 30 percent from watershed runoff, and 15 percent was backflow from Bean Lake. Although, Little Bean Marsh was both a ground-water recharge and discharge area, discharge to the marsh was three times the recharge to ground water. Ground-water levels closely tracked marsh water levels indicating a strong hydraulic connection between ground water and the marsh. Reduced surface runoff and ground-water availability are stabilizing influences on marsh hydrology and probably contribute to the persistence of emergent vegetation. The rapid hydraulic connection between Little Bean Marsh and ground water indicates that the hydrologic regime of most wetlands along the lower Missouri River is largely a function of the altitude of the marsh bottom relative to the altitude of the water table. More water was lost from the marsh through evapotranspiration (59 percent) than all other pathways combined. This is partially because the transpiration process of abundant macrophytes can greatly contribute to the evapotranspiration above that lost from open water surfaces. Surface outflow accounted for 36 percent and ground-water seepage accounted for only 5 percent of the losses. Large residence times allows the marsh to greatly affect water quality before water escapes as ground-water recharge or surface outflow. The shallowness of Little Bean Marsh and ion exclusion during ice formation caused the highest specific conductances of 1,100 to 1,300 microsiemens per centimeter at 25 degrees Celsius to occur during the winter. This concentration of dissolved solutes under ice can make wetlands more vulnerable to toxic contaminants than deeper surface-water bodies. Dissolved oxygen was less than 5 mg/L (milligrams per liter) for 3 to 4 months and near 0 mg/L for about 1 month in summer. Despite depths of less than 1 meter, temperature stratification persisted more than 3 months during the summers of 1996 and 1997, preventing mixing and contributing to periods of anoxia. Shallow depths and extended periods of anoxia in the marsh limit the ability of some organisms to escape high-temperature stress. Turbidity in Little Bean Marsh usually was low for several reasons: sediment loadings from the largely flood-plain drainage were low, emergent vegetation shade out algae and shield the water from wind, and high concentrations of bivalent cations increase flocculation rates of inorganic suspended material. The high concentrations of bivalent cations was largely because of a substantial amount of ground-water seepage into the marsh. Dissolved organic nitrogen was the dominant nitrogen species in Little Bean Marsh. Denitrification and biotic uptake kept more than 62 percent of nitrate (NO3) and 43 percent of ammonium (NH4) concentrations in marsh samples less than a detection limit of 0.005 mg/L. This contrasts with the Missouri River where inorganic NO3 dominates. Consequently, artificial flood-plain drainage that bypasses riparian wetlands likely deliver substantially more biotically available inorganic nitrogen to receiving waters than surface water that has been routed through a remnant wetland. Average total nitrogen concentrations in Little Bean Marsh were substantially less than those at other Missouri River wetlands, roughly one-half the mean concentrations in the Missouri River, but roughly twice the average nitrogen values in reservoirs of the glaciated plains of Missouri. The largest concentrations of nearly all species of nitrogen and phosphorus and the most intense period of hypereutrophy coincided with a phytoplankton bloom and senescence of River Bulrush (Scirpus fluviatilis) and common cattail (Typha latifolia) in September 1997. The rapid leaching of nitrogen that occurs soon after macrophyte senescence combined with a recent destratification of the marsh probably provided nitrogen to the nitrogen-limited open-water areas and triggered a phytoplankton bloom. Despite the rarity of runoff events, surface runoff from the watershed, combined with atmospheric deposition, contributed more than seven times the 530 kg (kilograms) of nitrogen that escaped Little Bean Marsh in surface outflow during 1997. Atmospheric deposition alone was more than 530 kg. Seepage to ground water contained less than 1.5 percent of the nitrogen leaving the marsh in surface outflow. The slow decay rate of Scirpus fluviatilis and reducing conditions in bottom sediments make burial of organic nitrogen a substantial sink of nitrogen. Denitrification experiments indicate that denitrification rates were limited by NO3 in the water column. Consequently, decomposition and nitrification of NH4 and organic nitrogen are the rate limiting steps of nitrogen removal in Little Bean Marsh. The NO3-limited rates of denitrification also indicate that Little Bean Marsh has a large unused capacity for nitrogen removal. These data indicate that the vast extent of riparian marshes along the Missouri and Mississippi Rivers may have had a substantial role in limiting NO3 loads to the Gulf of Mexico before agricultural development of flood plains. Drainage and removal of riparian marshes may be a major cause of the increased NO3 loads to the Gulf of Mexico. Periods of anoxia had much larger effects on phosphorus release than the other variables. The largest concentrations of phosphorus occurred in late summer and corresponded with senescing macrophytes, periods of anoxia, and a large algal bloom in Little Bean Marsh. Low water levels prevented the escape of phosphorus in surface outflow during these periods of highest phosphorus concentrations. Dry weather in late summer is typical and probably makes the correspondence of low water levels, anoxia, and consequent low phosphorus release a common occurrence in marshes along the Missouri River. Little Bean Marsh retained more than 95 percent of the phosphorus it received. The amount of phosphorus in surface inflows to the marsh were more than one order of magnitude greater than that escaping in surface outflows. The long hydraulic residence time of the marsh and large contributions of iron from ground water (that provide many sorption sites for phosphorus) make the marsh an effective sediment and phosphorus trap.

Missouri↗

Index of hydrologic data for selected sites in Palm Beach County, Florida, 1928-80

A regional assessment of the surficial aquifers in Dade, Broward , and Palm Beach Counties, Florida, including the Biscayne aquifer, was begun in 1979 by the U.S. Geological Survey, in cooperation with the South Florida Water Management District. The purpose of the first phase of the project was to determine the geologic, hydrologic, and water quality data available in the files of the U.S. Geological Survey and other public agencies. This report summarizes, through tables and maps, the types of data available for Palm Beach County.

Florida↗

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↗