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At least 973 records · Page 54Linked to original sources

The U.S. Geological Survey Federal-State Cooperative Water-Resources Program, fiscal year 1986

The U.S. Geological Survey 's Federal-State Cooperative Water Resources Program has been in operation for 91 years as of fiscal year (FY) 1986. Hydrologic data collection and interpretive investigations are underway in every State, Puerto Rico, and several territories in cooperation with more than 900 State, regional and local agencies. Federal funds amounted to $49.8 million in this 50-50 matching activity. Total funding was about $106 million, which included $6.9 million furnished by cooperating agencies on an unmatched basis. The Cooperative Program comprised more than 40% of the overall FY 1986 budget of the Survey 's Water Resources Division. The areas of principal emphasis during the year included groundwater contamination, stream quality, water supply and demand, and hydrologic hazards. Information is presented on program priorities and investigations implemented under the merit proposal process. The status of water use information activities, which are being carried out in 48 states and Puerto Rico is reviewed briefly. Standard methods for collecting the data are being developed. Each state has a computerized State Water-Use Data System for storage and retrieval of water-use data for individual users or facilities. (Lantz-PTT)

Open-File Report↗

Fresh and saline ground-water zones in the Punjab region, West Pakistan

An extensive program of test drilling and water sampling, undertaken by the Water and Soils Investigation Division (WASID) of the West Pakistan Water and Power Development Authority (WAPDA) to evaluate hydrologic problems related to waterlogging and soil salinity, has furnished data for the delineation of fresh and saline ground-water zones in the Punjab region of West Pakistan. Fresh ground water containing generally less than 500 ppm (parts per million) of total dissolved solids is found in wide belts paralleling the major rivers and in other areas of ground-water recharge. The fresh groundwater zone of upper (northeastern) Rechna Doab, where annual precipitation in places exceeds 30 inches, is the most extensive of the Punjab region and attains a depth of 1,700 feet or more below land surface near Gujranwala. Fresh ground water adjacent to the Indus River extends locally to depths of about l,500 feet. Saline ground water occurs downgradient from sources of recharge, particularly in the central parts of the interfluvial areas. Also, available data indicate a gradual increase in mineralization with depth and distance from sources of fresh-water recharge. Thus, even extensive fresh-water zones appear to be underlain, at variable depths, by saline ground water in most of the Punjab region. The saline ground waters of the Punjab region do not constitute, however, a distinct salt-water body that can be defined in terms of stratigraphic position, sea-level datum, particular lithology, or by chemical character. The ground waters of the Punjab region are characterized by a gradation from calcium magnesium bicarbonate types, near the sources of recharge, to waters containing a dominant proportion of sodium. Water containing from 500 to 1,000 ppm is commonly of the sodium bicarbonate type, or it may be of the mixed type, having about equal proportions of the common anions (bicarbonate, chloride, and sulfate). With increasing mineralization from about 1,000 to 3,000 ppm, ,the relative proportion of chloride and sulfate increases, and these waters are generally of the sodium chloride or sodium sulfate type. The highly mineralized waters of the Punjab region are generally of the sodium chloride type, whereas in Dera Ismail (D.I.) Khan District sodium sulfate waters predominate. The ground waters from more than 900 sampling sites have been classified into eight types, according to dominant cations and anions. These types have been further subdivided into groups containing different amounts of total dissolved solids. The pattern of distribution of saline ground-water zones in the Punjab region and the observed gradual increase in mineral content, downgradient from sources of fresh-water recharge, can be explained best by the processes of evaporation from the water table and solution of minerals within the alluvial aquifer.

Water Supply Paper↗

Surface-water quality in the West Branch Susquehanna River basin, Pennsylvania: An appraisal of areal and temporal variability from 1962 to 1982 in hydrologic accounting unit 020502

The West Branch Susquehanna River basin has a drainage area of 6,955 square miles in north-central Pennsylvania and comprises Hydrologic Accounting Unit 020502. A National Stream Quality Accounting Network (NASQAN) waterquality data collection site, maintained by the U.S. Geological Survey, is located on the river near its mouth at Lewisburg, Pennsylvania. Water-quality data are collected at numerous other sites throughout the basin by the Pennsylvania Department of Environmental Resources, Bureau of Water Quality Management. Data collected from the NASQAN site and the sites operated by the Pennsylvania Department of Environmental Resources from 1962 to 1982 were used to evaluate water-quality variability in the basin. The following objectives were addressed: (1) describe the surface-water quality upstream of the NASQAN site on an areal and temporal basis; (2) relate the water-quality variability, on both an areal and temporal basis, to general basin characteristics; and (3) assess the ability of the water-quality data collected at the NASQAN site to represent, on both an areal and temporal basis the water quality for Hydrologic Accounting Unit 020502 upstream from the site. Areally, the water quality varies considerably throughout the basin. Generally, the river was found to have moderately good water quality in the upper reaches, poor water quality in its middle reach, and good water quality near the mouth. Two tributaries, Moshannon Creek (median pH 3.9) and Bald Eagle Creek (median pH 7.8), had the most pronounced effect on the water quality of the river. Temporal trends were found in the concentrations of several of the constituents at most of the stations. Of the constituents analyzed, those which exhibited increasing or decreasing trends most frequently were pH, alkalinity, dissolved sulfate, total ammonia, and total nitrite plus nitrate. The largest trends were in the concentrations of total-recoverable aluminum, manganese, and zinc. Causes of areal variation were attributed to land use and geologic variations throughout the basin. Trends which indicated an improvement in water qualijty are believed to be caused by improvements in the treatment of acid mine drainage and wastewater. Trends which indicated degradation of water quality were generally found in areas where these types of treatment are not yet effective. The NASQAN site at Lewisburg was shown not to represent the water quality of the entire basin, either areally or temporally. It does, however, represent the water quality of the West Branch Susquehanna River at its mouth.

Pennsylvania↗

Application of near-surface geophysics as part of a hydrologic study of a subsurface drip irrigation system along the Powder River floodplain near Arvada, Wyoming

Rapid development of coalbed natural gas (CBNG) production in the Powder River Basin (PRB) of Wyoming has occurred since 1997. National attention related to CBNG development has focused on produced water management, which is the single largest cost for on-shore domestic producers. Low-cost treatment technologies allow operators to reduce their disposal costs, provide treated water for beneficial use, and stimulate oil and gas production by small operators. Subsurface drip irrigation (SDI) systems are one potential treatment option that allows for increased CBNG production by providing a beneficial use for the produced water in farmland irrigation. Water management practices in the development of CBNG in Wyoming have been aided by integrated geophysical, geochemical, and hydrologic studies of both the disposal and utilization of water. The U.S. Department of Energy (DOE) National Energy Technology Laboratory (NETL) and the U.S. Geological Survey (USGS) have utilized multi-frequency airborne, ground, and borehole electromagnetic (EM) and ground resistivity methods to characterize the near-surface hydrogeology in areas of produced water disposal. These surveys provide near-surface EM data that can be compared with results of previous surveys to monitor changes in soils and local hydrology over time as the produced water is discharged through SDI. The focus of this investigation is the Headgate Draw SDI site, situated adjacent to the Powder River near the confluence of a major tributary, Crazy Woman Creek, in Johnson County, Wyoming. The SDI system was installed during the summer of 2008 and began operation in October of 2008. Ground, borehole, and helicopter electromagnetic (HEM) conductivity surveys were conducted at the site prior to the installation of the SDI system. After the installation of the subsurface drip irrigation system, ground EM surveys have been performed quarterly (weather permitting). The geophysical surveys map the heterogeneity of the near-surface geology and hydrology of the study area. The geophysical data are consistent between surveys using different techniques and between surveys carried out at different times from 2007 through 2011. This paper summarizes geophysical results from the 4-year monitoring study of the SDI system.

Wyoming↗

Climate and human water use diminish wetland networks supporting continental waterbird migration

Migrating waterbirds moving between upper and lower latitudinal breeding and wintering grounds rely on a limited network of endorheic lakes and wetlands when crossing arid continental interiors. Recent drying of global endorheic water stores raises concerns over deteriorating migratory pathways, yet few studies have considered these effects at the scale of continental flyways. Here, we investigate the resiliency of waterbird migration networks across western North America by reconstructing long-term patterns (1984–2018) of terminal lake and wetland surface water area in 26 endorheic watersheds. Findings were partitioned regionally by snowmelt- and monsoon-driven hydrologies and combined with climate and human water-use data to determine their importance in predicting surface water trends. Nonlinear patterns of lake and wetland drying were apparent along latitudinal flyway gradients. Pervasive surface water declines were prevalent in northern snowmelt watersheds (lakes −27%, wetlands −47%) while largely stable in monsoonal watersheds to the south (lakes −13%, wetlands +8%). Monsoonal watersheds represented a smaller proportion of total lake and wetland area, but their distribution and frequency of change within highly arid regions of the continental flyway increased their value to migratory waterbirds. Irrigated agriculture and increasing evaporative demands were the most important drivers of surface water declines. Underlying agricultural and wetland relationships however were more complex. Approximately 7% of irrigated lands linked to flood irrigation and water storage practices supported 61% of all wetland inundation in snowmelt watersheds. In monsoonal watersheds, small earthen dams, meant to capture surface runoff for livestock watering, were a major component of wetland resources (67%) that supported networks of isolated wetlands surrounding endorheic lakes. Ecological trends and human impacts identified herein underscore the importance of assessing flyway-scale change as our model depictions likely reflect new and emerging bottlenecks to continental migration.

Global Change Biology↗

Selected hydrologic data, Chester County, Pennsylvania

This report presents selected hydrologic data collected during a study of the ground-water resources of Chester County, Pennsylvania. The study was made during 1973-76 by the U. S. Geological Survey in cooperation with the Chester County Water Resources Authority. This report is intended to make the data conveniently available and to supplement an interpretive report that will be published separately.

Pennsylvania↗

Collection, storage, retrieval, and publication of water-resources data

This publication represents a series of papers devoted to the subject of collection, storage, retrieval, and publication of hydrologic data. The papers were presented by members of the U.S. Geological Survey at the International Seminar on Organization and Operation of Hydrologic Services, Ottawa, Canada, July 15-16, 1976, sponsored by the World Meteorological Organization. The first paper, ' Standardization of Hydrologic Measurements, ' by George F. Smoot discusses the need for standardization of the methods and instruments used in measuring hydrologic data. The second paper, ' Use of Earth Satellites for Automation of Hydrologic Data Collection, ' by Richard W. Paulson discusses the use of inexpensive battery-operated radios to transmit realtime hydrologic data to earth satellites and back to ground receiving stations for computer processing. The third paper, ' Operation Hydrometeorological Data-Collection System for the Columbia River, ' by Nicholas A. Kallio discusses the operation of a complex water-management system for a large river basin utilizing the latest automatic telemetry and processing devices. The fourth paper, ' Storage and Retrieval of Water-Resources Data, ' by Charles R. Showen discusses the U.S. Geological Survey 's National Water Data Storage and Retrieval System (WATSTORE) and its use in processing water resources data. The final paper, ' Publication of Water Resources Data, ' by S. M. Lang and C. B. Ham discusses the requirement for publication of water-resources data to meet the needs of a widespread audience and for archival purposes. (See W78-09324 thru W78-09328) (Woodard-USGS)

Circular↗

Chester County ground-water atlas, Chester County, Pennsylvania

Chester County encompasses 760 square miles in southeastern Pennsylvania. Groundwater-quality studies have been conducted in the county over several decades to address specific hydrologic issues. This report compiles and describes water-quality data collected during studies conducted mostly after 1990 and summarizes the data in a county-wide perspective. In this report, water-quality constituents are described in regard to what they are, why the constituents are important, and where constituent concentrations vary relative to geology or land use. Water-quality constituents are grouped into logical units to aid presentation: water-quality constituents measured in the field (pH, alkalinity, specific conductance, and dissolved oxygen), common ions, metals, radionuclides, bacteria, nutrients, pesticides, and volatile organic compounds. Water-quality constituents measured in the field, common ions (except chloride), metals, and radionuclides are discussed relative to geology. Bacteria, nutrients, pesticides, and volatile organic compounds are discussed relative to land use. If the U.S. Environmental Protection Agency (USEPA) or Chester County Health Department has drinking water standards for a constituent, the standards are included. Tables and maps are included to assist Chester County residents in understanding the water-quality constituents and their distribution in the county. Ground water in Chester County generally is of good quality and is mostly acidic except in the carbonate rocks and serpentinite, where it is neutral to strongly basic. Calcium carbonate and magnesium carbonate are major constituents of these rocks. Both compounds have high solubility, and, as such, both are major contributors to elevated pH, alkalinity, specific conductance, and the common ions. Elevated pH and alkalinity in carbonate rocks and serpentinite can indicate a potential for scaling in water heaters and household plumbing. Low pH and low alkalinity in the schist, quartzite, and gneiss rocks can indicate a potential for corrosive water. The only constituent measured in the field that has a USEPA Secondary Maximum Contaminant Level (SMCL) is pH. The SMCL for pH is 6.5-8.5; 64 percent of samples analyzed for pH were acidic (below pH 6.5). Only 1 percent of samples were basic (above pH 8.5). Of the common ions, the USEPA has SMCLs for chloride, sulfate, and total dissolved solids. The USEPA has a SMCL and a Primary Maximum Contaminant Level (PMCL) for fluoride. Chloride is more closely related to land use than geology. In Chester County, chloride exceeded the SMCL (250 mg/L) only in 5 percent of the services (commercial services, community services, and military) land-use areas. No samples analyzed for sulfate exceeded the SMCL (250 mg/L). Only 3 percent of samples analyzed for total dissolved solids exceeded the SMCL (500 milligrams per liter) (mg/L). No samples analyzed for fluoride equaled or exceeded the SMCL (2.0 mg/L) or PMCL (4.0 mg/L). Iron concentrations exceeded the USEPA SMCL in 11 percent of samples and were highest in schist (14 percent) and gneiss (13 percent). Manganese concentrations exceeded the SMCL in 19 percent of samples and were highest in quartzite and schist (both 28 percent). Lead and arsenic were present in low concentrations: the highest concentrations of lead occurred in water from quartzite (8 percent exceeded the USEPA Action Level), and arsenic was detected mostly in Triassic sedimentary rocks (9 percent exceeded the USEPA PMCL). The highest concentrations of copper occurred more frequently in quartzite rocks, and to a lesser extent were evenly distributed between ground water in gneiss, schist, and Triassic sedimentary rocks. Elevated concentrations of radon-222 and the combined radium-226/radium-228 radionuclides were common in water from quartzite and schist. Gross alpha and gross beta particle activities were elevated in water from quartzite and carbonate rocks. In contrast, elevated concentrations of uranium primarily were measured in water from Triassic sedimentary and carbonate rocks. Despite a sampling bias towards agricultural land use, only two samples indicated the presence of fecal coliforms. Samples analyzed for nutrients generally exhibited low concentrations, but about 11 percent of samples collected for nitrate exceeded the USEPA PMCL. Only one nitrite sample (less than 1 percent) exceeded the respective USEPA PMCL. Approximately 190 samples were collected for each of the three pesticides in this report: lindane, dieldrin, and diazinon. Sampling was biased towards agricultural, low-medium density residential, and wooded land uses. Approximately 95 percent of samples for each pesticide were below minimum reporting levels (MRL). Only lindane has a USEPA PMCL, and only one sample exceeded the standard. Results for dieldrin and diazinon were similar, except results for two diazinon samples where concentrations were 57.0 and 490 micrograms per liter (μg/L). Volatile organic compounds in this report were analyzed in water from 198 samples. Sampling was biased towards agricultural, low-medium density residential, and wooded land uses. Two percent of samples analyzed for trichloroethylene and less than 1 percent of samples analyzed for tetrachloroethylene exceeded their respective USEPA PMCLs (each 5.0 μg/L). No samples analyzed for 1,1,1-trichloroethane exceeded the USEPA PMCL (200 μg/L). No samples analyzed for methyl tert-butyl ether exceeded the USEPA Drinking Water Advisory (20μg/L).

Open-File Report↗

Hydrologic and chemical data for wells, springs, and streams in Nevada, TPS. 1-21 N., and Rs. 41-57 E

Studies of published and unpublished geologic, hydrologic, and chemical-quality data for ground and surface water in central Nevada, Tps. 1 to 21 N. and Rs. 41 to 57 E., Mount Diablo base and meridian, reveal the following information: Rocks exposed in central Nevada are of sedimentary and igneous origin and range in age from Cambrian to Recent. Rocks of Paleozoic age generally are carbonate or clastic, and rocks of Mesozoic age generally are clastic and granitic. Rocks of Tertiary age principally are volcanic, and the valley fill of Quaternary age is alluvial-fan and lake deposits. The rocks are folded, faulted, and highly fractured. Precipitation is closely related to altitude. In general, as the altitude increases the precipitation increases. Most of the streamflow in the valleys originates as snow in the nearby mountains. The streams generally flow only in response to snowmelt and to flash-flood-producing storms. Important chemical quality characteristics of the ground and surface water in central Nevada are hardness, expressed as CaCO 3 , generally in excess of 120 ppm, and a dissolved-solids content of less than 500 ppm. The principal chemical types of both ground and surface waters are sodium and calcium bicarbonates. The major uses of ground water in central Nevada are for irrigation and stock. Frequency of use of wells in decreasing order is: irrigation, stock, domestic, industrial, municipal, and observation. Of the 606 wells tabulated, 29 have multiple uses. Frequency of use of spring water in decreasing order is: stock, irrigation, domestic, and public facilities. Of the 135 springs tabulated, 5 have multiple uses.

Nevada↗

Selected hydrologic data, Arkansas River basin, Pueblo and southeastern Fremont Counties, Colorado, 1975-80

Selected hydrologic data collected in 1975-80 as part of water-quality investigations by the U.S. Geological Survey in Pueblo and southeastern Fremont Counties, Colo., are presented in this report. The data, in tabular form, consist of streamflow-discharge measurements for 33 sites, channel-geometry measurements for 97 sites, traveltime data for 12 sites, and field and laboratory water-quality analyses for 194 sites. Federal, state, and local officials may find these data useful in making decisions relating to the management of water resources of the area.

Colorado↗

Hydrologic data from Naval Oil Shale Reserves, Parachute Creek basin, northwestern Colorado, 1980-81

Two years (water yr 1980 and 1981) of data collected by the U.S. Geological Survey for the U.S. Department of Energy, Naval Petroleum and Oil Shale Reserves, in the Parachute Creek drainage basin of northwestern Colorado are tabulated. Data were obtained from five surface water gages, two automatic sediment samplers, and two water quality monitors. Climate data include maximum, minimum, and average temperature and relative humidity, average wind speed and wind direction, and total daily solar radiation. Daily total precipitation is reported for three stations, and snow-course data reported for one site. (Author 's abstract)

Open-File Report↗

Summary of water-resources activities of the U.S. Geological Survey in Colorado: Fiscal year 1987

The annual summary of water-resources activities in Colorado is presented for fiscal year 1987. The report includes an introduction of these activities and names of the management personnel to whom information requests may be addressed; a summary of the U.S. Geological Survey mission and of the Water Resources Division mission; and a discussion of the water resources in Colorado in fiscal year 1987, including data collection on surface water and groundwater. All current Colorado hydrologic investigations are listed - their problems, objectives, approaches, progress, and plans for fiscal year 1987. A list of current cooperators for fiscal year 1987 and a list of reports published or released during fiscal year 1987 also are given.

Colorado↗

Summary of water-resources activities of the U.S. Geological Survey in Colorado– Fiscal year 1989

The biennial summary of water resources activities in Colorado is presented for fiscal year 1989. The report includes an introduction of these activities and names of the management personnel to whom information requests may be addressed, a summary of the U.S. Geological Survey mission and of the Water Resources Division mission, and a discussion of the water resources in Colorado in fiscal year 1989, including data collection on surface water and groundwater. All current Colorado hydrologic investigations are listed--their problems, objectives, approaches, progress, and plans for fiscal year 1989. A list of current cooperators, for fiscal year 1989 and a list of reports published or released during fiscal years 1987, 1988, and 1989 also are given. (USGS)

Colorado↗

Lithostratigraphy, geophysics, biostratigraphy, and strontium-isotope stratigraphy of the surficial aquifer system of eastern Collier County and northern Monroe County, Florida

In 1997, ten cores were drilled in eastern Collier County and northern Monroe County, within the limits of the Big Cypress National Preserve. These cores represent a continuation of the study of seven cores in western Collier County begun in 1996 and reported in Weedman and others (1997) and Edwards and others (1998). This joint U.S. Geological Survey and Florida Geological Survey project is designed to acquire subsurface geologic and hydrologic data in southwest Florida to extend current ground-water models, thereby expanding the utility of these models for land and water management. In this report we describe the lithostratigraphy, geophysical logging, sedimentological analysis, dinocyst biostratigraphy, and strontium-isotope stratigraphy of these ten cores. The three geophysical logs (natural gamma-ray, induction conductivity, and neutron porosity) assumed to be related to formation lithology and water quality show that a number of clay-rich zones are present in all of the boreholes, and that pore-water conductivity increases with depth. The clay-rich zones are confirmed by visual examination of core material and sedimentological analysis. The relative transmissivity calculated at 10-foot-thick intervals shows that in six of the boreholes, high values are associated with the shallow aquifer in the 0-40 ft interval. Two of the boreholes (the most northerly and the most easterly) showed relatively higher values of transmissivity in permeable zones at or somewhat below 100 ft in depth. Core geology and logs indicate that the deeper aquifers are not more permeable than similar deeper zones in the other boreholes, but rather that the shallow aquifer appears to be less permeable in these two coreholes. The Arcadia (?) Formation was only penetrated in the deepest core where it is late Miocene in age. The Peace River Formation was penetrated in all but the two westernmost cores. It yields a late Miocene age, based on both dinocysts and strontium-isotope stratigraphy. The top is an irregular surface. Age and stratigraphic relations suggest that the upper part of the Peace River and lower part of the unnamed formation are at least partially equivalent laterally. The unnamed formation was recovered in every core. It is thinnest in the northernmost core and thickest to the west. Ages calculated from strontium isotopes range from 6.9 to 4.6 million years ago (late Miocene to early Pliocene). The top of the unnamed formation is deepest to the north and it becomes shallower to the southwest. The Tamiami Formation also was recovered in every core and consistently yields early Pliocene ages; it yields late Pliocene ages near the top in two cores. The age and lateral relations strongly suggest that the lower part of the Tamiami Formation and the upper part of the unnamed formation are lateral facies of each other. The Fort Thompson (?) Formation, Miami Limestone, and undifferentiated siliciclastic sediments and limestone at the very top of the cores were not dated.

Florida↗

Using regional watershed data to assess water-quality impairment in the Pacific Drainages of the United States

Two datasets containing the first complete estimates of reach-scale nutrient, water use, dissolved oxygen, and pH conditions for the Pacific drainages of the United States were created to help inform water-quality management decisions in that region. The datasets were developed using easily obtainable watershed data, most of which have not been available until recently, and the techniques that were used provide a framework for integrating watershed data to assess water-quality impairment across other large hydrologic regions in the United States. These datasets were used to summarize regional nutrient and water-use conditions within impaired water bodies and to summarize regional dissolved oxygen concentrations and pH conditions for free-flowing stream reaches. Two examples are also presented that show how the datasets can be applied to specific water-quality management issues: (1) nutrient conditions in water bodies that have recently experienced problems with harmful algal blooms; and (2) dissolved oxygen and pH conditions in stream reaches likely to be populated by steelhead trout ( Oncorhynchus mykiss irideus ) during their summer run. The nutrient and water-use estimates could help inform actions aimed at managing water-quality conditions in impaired water bodies while the dissolved oxygen and pH predictions could be useful as screening tools to identify water bodies experiencing potential impairment.

California, Idaho, Montana, Nevada, Oregon, Utah, ↗

Water resources of the Menominee Indian Reservation of Wisconsin

Water resources of the Menominee Indian Reservation, Wisconsin, were investigated during the period October 1981 through September 1987. The report presents baseline data and some interpretation of ground- and surface-water hydrology and quality of the Reservation. The area stratigraphy consists of basal Precambrian crystalline bedrock and overlying till and sand and gravel deposits. In the Reservation, the glacial deposits range in thickness from zero to 180 feet. The bedrock aquifer is composed of fractured and weathered Precambrian bedrock within about 20 feet of the upper bedrock surface. The sand and gravel aquifer is composed of saturated, permeable sand and gravel that occurs as layers, lenses, terrace deposits, and valley fillings. The glacial material has a saturated thickness ranging from approximately 150 feet to zero feet in areas where the Precambrian bedrock crops out. Water-table conditions commonly occur in both aquifers. Horizontal hydraulic conductivity of the sand and gravel and bedrock aquifers is estimated to be 5 and 0.3 feet per day, respectively. The Wolf River and its tributaries drain the Reservation except for the eastern quarter, which is drained by the South Branch of the Oconto River. The average discharge of the Wolf River, monitored continuously during 1907-85 at Keshena Falls near Keshena, was 762 ft 3/s (cubic feet per second). Maximum instantaneous discharge was 5,200 ft3/s recorded on March 15, 1973, and the minimum was 91 ft3/s recorded on December 22,1939. Low flow and flood-frequency characteristics for the Wolf River were estimated using mean-daily discharge for the period of record at Keshena Falls. Ground water from the sand and gravel and bedrock aquifers is a calcium magnesium bicarbonate type. The composition of waters from the two aquifers is similar because water recharging the bedrock aquifer is from the overlying sand and gravel aquifer. Iron or manganese concentrations exceeding secondary maximum contaminant levels were found in water samples from approximately one-quarter to one-half of the wells sampled. Approximately three-quarters of the groundwater sampled during the study is moderately hard to very hard, with a median hardness equal to 171 mg/L (milligrams per liter) (as calcium carbonate)for the sand and gravel aquifer and 165mg/L (as calcium carbonate) for the bedrock aquifer. Alkalinity of the ground water ranged from26 to 211 mg/L, with a median value of 182 mg/L(as calcium carbonate) for the sand and gravel aquifer and ranged from 72 to 250 mg/L, with a median value of 170 mg/L (as calcium carbonate)for the bedrock aquifer. Water samples collected from Reservation streams and lakes were similar to ground water (calcium magnesium bicarbonate type), reflecting the strong surface-water/ground-water interaction in the study area. The chemical composition of water from lakes having inlets or outlets indicate that they are not influenced by precipitation as much as lakes that do not have inlets or outlets.

Wisconsin↗

Simulated effects of water exchanges on streamflow and specific conductance in the Arkansas River upstream from Avondale, Colorado

The potential effects of future water-exchange scenarios on streamflow and specific conductance in the Arkansas River were simulated with two accounting models. The major processes in the models simulated the historical exchange potential in the Arkansas River and the operation of a native and a nonnative Arkansas River water exchange. The potential effects of future exchange conditions were simulated using streamflow and specific-conductance data from the 1986-93 water-year study period. Hydrologic conditions during the study period were considered about average, compared to the long-term 1966-96 conditions. Therefore, the simulation results were indicative of the potential effects of future exchange conditions on streamflow and specific conductance during periods of average hydrologic conditions.

Colorado↗

Selected hydrologic data, San Pitch River drainage basin, Utah

The u.s. Geological Survey investigated the ground-water resources of the San Pitch River drainage basin during the period 1964- 67. The investigation was a cooperative project, financed equally by the Utah Department of Natural Resources, Division of Water Rights, and the Federal Government, and was a part of an investigation of the groundwater resources of the entire Sevier River drainage system. This report is intended to serve two purposes: (1) To make available to the public basic water-resources data useful in planning and studying development of water resources and (2) to supplement an interpretive report that will be published later. Included in the release are data collected by the Geological Survey since 1930.

Utah↗