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At least 631 records · Page 35Linked to original sources
USGS1984

Hydrologic and climatologic data for the Lehigh area, southeastern Oklahoma, May 1977 to January 1982

Hydrologic and climatologic data were collected in the Lehigh area in southeastern Oklahoma during an investigation of the hydrologic effects of coal strip-mining. The purpose of the study was to assess the probable effects of surface mining for coal and subsequent reclamation on the hydrologic characteristics of the basin. This report presents all the data collected between 1977 and 1982. The data include: (1) greater than four years of daily and selected unit streamflow, daily suspended-sediment discharge, analyses of periodic samples for chemical quality, and daily temperature, pH, specific conductance, and dissolved oxygen at the Coal Creek near Lehigh gaging stations; (2) partial record discharge data and analyses of periodic samples for chemical quality and sediment for two tributaries of Coal Creek; (3) climatologic data for four sites; (4) soil moisture at 13 measurements sites; (5) continuous record of the water level in one well; (6) periodic record of water level in a second well; (7) water-level records for 43 wells and springs including on-site measurement of physical parameters; and (8) complete chemical analyses of water samples from eleven wells and one spring.

Oklahoma↗
USGS2014

Developing and testing temperature models for regulated systems: a case study on the Upper Delaware River

Water temperature is an important driver of many processes in riverine ecosystems. If reservoirs are present, their releases can greatly influence downstream water temperatures. Models are important tools in understanding the influence these releases may have on the thermal regimes of downstream rivers. In this study, we developed and tested a suite of models to predict river temperature at a location downstream of two reservoirs in the Upper Delaware River (USA), a section of river that is managed to support a world-class coldwater fishery. Three empirical models were tested, including a Generalized Least Squares Model with a cosine trend (GLScos), AutoRegressive Integrated Moving Average (ARIMA), and Artificial Neural Network (ANN). We also tested one mechanistic Heat Flux Model (HFM) that was based on energy gain and loss. Predictor variables used in model development included climate data (e.g., solar radiation, wind speed, etc.) collected from a nearby weather station and temperature and hydrologic data from upstream U.S. Geological Survey gages. Models were developed with a training dataset that consisted of data from 2008 to 2011; they were then independently validated with a test dataset from 2012. Model accuracy was evaluated using root mean square error (RMSE), Nash Sutcliffe efficiency (NSE), percent bias (PBIAS), and index of agreement (d) statistics. Model forecast success was evaluated using baseline-modified prime index of agreement (md) at the one, three, and five day predictions. All five models accurately predicted daily mean river temperature across the entire training dataset (RMSE = 0.58–1.311, NSE = 0.99–0.97, d = 0.98–0.99); ARIMA was most accurate (RMSE = 0.57, NSE = 0.99), but each model, other than ARIMA, showed short periods of under- or over-predicting observed warmer temperatures. For the training dataset, all models besides ARIMA had overestimation bias (PBIAS = −0.10 to −1.30). Validation analyses showed all models performed well; the HFM model was the most accurate compared other models (RMSE = 0.92, both NSE = 0.98, d = 0.99) and the ARIMA model was least accurate (RMSE = 2.06, NSE = 0.92, d = 0.98); however, all models had an overestimation bias (PBIAS = −4.1 to −10.20). Aside from the one day forecast ARIMA model (md = 0.53), all models forecasted fairly well at the one, three, and five day forecasts (md = 0.77–0.96). Overall, we were successful in developing models predicting daily mean temperature across a broad range of temperatures. These models, specifically the GLScos, ANN, and HFM, may serve as important tools for predicting conditions and managing thermal releases in regulated river systems such as the Delaware River. Further model development may be important in customizing predictions for particular biological or ecological needs, or for particular temporal or spatial scales.

Delaware, New York, Pennsylvania↗
USGS2009

Sources of uncertainty in flood inundation maps

Flood inundation maps typically have been used to depict inundated areas for floods having specific exceedance levels. The uncertainty associated with the inundation boundaries is seldom quantified, in part, because all of the sources of uncertainty are not recognized and because data available to quantify uncertainty seldom are available. Sources of uncertainty discussed in this paper include hydrologic data used for hydraulic model development and validation, topographic data, and the hydraulic model. The assumption of steady flow, which typically is made to produce inundation maps, has less of an effect on predicted inundation at lower flows than for higher flows because more time typically is required to inundate areas at high flows than at low flows. Difficulties with establishing reasonable cross sections that do not intersect and that represent water-surface slopes in tributaries contribute additional uncertainties in the hydraulic modelling. As a result, uncertainty in the flood inundation polygons simulated with a one-dimensional model increases with distance from the main channel.

Journal of Flood Risk Management↗
USGS2022

Mapping structural control through analysis of land-surface deformation for the Rialto-Colton groundwater subbasin, San Bernardino County, California, 1992–2010

The locations of many faults in and near the Rialto-Colton groundwater subbasin are not precisely known because the spatial density of existing lithologic and hydrologic data used to infer the locations of faults can be sparse. The U.S. Geological Survey, in cooperation with the San Bernardino Valley Municipal Water District, analyzed structural control of groundwater flow in and near the Rialto-Colton groundwater subbasin using Interferometric Synthetic Aperture Radar (InSAR) methods. Faults commonly are barriers to groundwater flow, and the high spatial resolution of InSAR imagery can be used to infer the locations of buried faults where groundwater pumping occurs. InSAR results have revealed three areas in and near the Rialto-Colton groundwater subbasin where buried faults are interpreted as groundwater-flow barriers: the northwestern area about 3 miles northwest of the City of Rialto, the San Jacinto fault area west of the City of San Bernardino, and the southeastern area about 2 miles southeast of the City of Colton. The InSAR results were combined with knowledge gained from previous studies to better define the location and extent of faults acting as groundwater-flow barriers. New data about faults acting as groundwater-flow barriers can be incorporated into future conceptual and hydrologic models of the Rialto-Colton groundwater subbasin and provide water managers information to help effectively manage groundwater resources.

California↗
USGS2004

Hydrogeologic characterization of the Modesto Area, San Joaquin Valley, California

Hydrogeologic characterization was done to develop an understanding of the hydrogeologic setting near Modesto by maximizing the use of existing data and building on previous work in the region. A substantial amount of new lithologic and hydrologic data are available that allow a more complete and updated characterization of the aquifer system. In this report, geologic units are described, a database of well characteristics and lithology is developed and used to update the regional stratigraphy, a water budget is estimated for water year 2000, a three-dimensional spatial correlation map of aquifer texture is created, and recommendations for future data collection are summarized. The general physiography of the study area is reflected in the soils. The oldest soils, which have low permeability, exist in terrace deposits, in the interfan areas between the Stanislaus, Tuolumne, and Merced Rivers, at the distal end of the fans, and along the San Joaquin River floodplain. The youngest soils have high permeability and generally have been forming on the recently deposited alluvium along the major stream channels. Geologic materials exposed or penetrated by wells in the Modesto area range from pre-Cretaceous rocks to recent alluvium; however, water-bearing materials are mostly Late Tertiary and Quaternary in age. A database containing information from more than 3,500 drillers'logs was constructed to organize information on well characteristics and subsurface lithology in the study area. The database was used in conjunction with a limited number of geophysical logs and county soil maps to define the stratigraphic framework of the study area. Sequences of red paleosols were identified in the database and used as stratigraphic boundaries. Associated with these paleosols are very coarse grained incised valley-fill deposits. Some geophysical well logs and other sparse well information suggest the presence of one of these incised valley-fill deposits along and adjacent to the Tuolumne River east of Modesto, a feature that may have important implications for ground-water flow and transport in the region. Although extensive work has been done by earlier investigators to define the structure of the Modesto area aquifer system, this report has resulted in some modification to the lateral extent of the Corcoran Clay and the regional dip of the Mehrten Formation. Well logs in the database indicating the presence of the Corcoran Clay were used to revise the eastern extent of the Corcoran Clay, which lies approximately parallel to the axis of valley. The Mehrten Formation is distinguished in the well-log database by its characteristic black sands consisting of predominantly andesitic fragments. Black sands in wells listed in the database indicate that the formation may lie as shallow as 120 meters (400 feet) below land surface under Modesto, approximately 90 meters (300 feet) shallower than previously thought. The alluvial aquifer system in the Modesto area comprises an unconfined to semiconfined aquifer above and east of the Corcoran Clay confining unit and a confined aquifer beneath the Corcoran Clay. The unconfined aquifer is composed of alluvial sediments of the Modesto, Riverbank, and upper Turlock Lake formations. The unconfined aquifer east of the Corcoran Clay becomes semiconfined with depth due to the numerous discontinuous clay lenses and extensive paleosols throughout the aquifer thickness. The confined aquifer is composed primarily of alluvial sediments of the Turlock Lake and upper Mehrten Formations, extending from beneath the Corcoran Clay to the base of fresh water. Ground water in the unconfined to semiconfined aquifer flows to the west and southwest. The primary source of present-day recharge is percolating excess irrigation water. The primary ground-water discharge is extensive ground-water pumping in the unconfined to semiconfined aquifer, imposing a significant component of vertical flow in the system. A water budget was calculated for water year 2000 using a land-use approach. During water year 2000, the total water supply in the Modesto area was more than 2.5 billion m3 (cubic meter) (2 million acre-ft [acre-foot]). Surface-water deliveries accounted for 60 percent of the total water supply, whereas ground-water pumpage accounted for 40 percent. Ninety-four percent of the water supply was used to meet irrigation demand and approximately 6 percent was used to meet urban demand. The total recharge in the model area was estimated at 1.4 billion m3 (1,100,000 acre-ft). The largest component of recharge is from excess irrigation water (58 percent); precipitation in excess of crop requirements accounted for 41 percent of the recharge. Geostatistical methods were used to develop a spatial correlation model of the percentage of coarse-grained texture in the Modesto area. The mean percentage coarse-grained texture calculated for each depth increment indicates a regional trend of decreasing coarse-grained texture with increasing depth, which is consistent with increasingly consolidated sediments with depth in the study area. The three-dimensional kriged estimates of percentage coarse-grained texture show significant heterogeneity in the texture of the sedimentary deposits. Assuming the hydraulic conductivity is correlated to the texture, the kriged result implies significant heterogeneity in the hydrogeologic framework.

California↗
USGS1991

Chemical and physical data related to ground water in the vicinity of abandoned uraniferous lignite mines, western North Dakota, December 1983 through June 1988

Geochemical and hydrologic data were collected in and around six abandoned uranlferous lignite mines in western North Dakota during December 1983 through June 1988. These data Include well construction and field water-quality data for 224 wells, test holes, and springs. Also Included are water levels in selected wells, lithologlc logs of selected wells and test holes, physical properties and major-Ion and nutrient concentrations of water samples from selected wells and springs, trace-element analyses of water samples from selected wells and springs, radlochemlcal analyses of water samples from selected wells and springs, and grain-size analyses of rock samples from selected wells and test holes. Analytical methods and detection levels for determination of chemical constituents are Included as well as township-range location numbers and corresponding latitude-longitude numbers.

Open-File Report↗
USGS1996

Overview of surface-water resources at the U.S. Coast Guard Support Center Kodiak, Alaska, 1987-89

Hydrologic data at a U.S. Coast Guard Support Center on Kodiak Island, Alaska, were collected from 1987 though 1989 to determine hydrologic conditions and if contamination of soils, ground water, or surface water has occurred. This report summarizes the surface-water-discharge data collected during the study and estimates peak, average, and low-flow values for Buskin River near its mouth. Water-discharge measurements were made at least once at 48 sites on streams in or near the Center. Discharges were measured in the Buskin River near its mouth five times during 1987-89 and ranged from 27 to 367 cubic feet per second. Tributaries of Buskin River below Buskin Lake that had discharges greater than 1 cubic foot per second include Bear Creek, Alder Creek, Magazine Creek, Devils Creek and an outlet from Lake Louise. Streams having flows generally greater than 0.1 cubic foot per second but less than 1 cubic foot per second include an unnamed tributary to Buskin River, an unnamed tributary to Lake Catherine and a drainage channel at Kodiak airport. Most other streams flowing into Buskin River, and all streams on Nyman Peninsula, usually had little or no flow except during periods of rainfall or snowmelt. During a low-flow period in February 1989, discharge measurements in Buskin River and its tributaries indicate that three reaches of Buskin River below Buskin Lake lost water to the ground-water system, whereas two reaches gained water; the net gain in streamflow attributed to ground-water inflow at a location near the mouth was estimated to be 2.2 cubic feet per second. The 100-year peak flow for Buskin River near its mouth was estimated to be 4,460 cubic feet per second. Average discharge was estimated to be 125 cubic feet per second and the 7-day 10-year low flow was estimated to be 5.8 cubic feet per second.

Alaska↗
USGS1974

Pesticides data-collection activities of the U.S. Geological Survey in Texas

The water-resources investigations program of the Geological Survey has the objective of seeing that the Nation's water resources are appraised and that the necessary water data to develop and manage them efficiently are available when needed. In carrying out this objective, the Survey is the primary source of hydrologic data that are basic not only to the quantification of the water resource but also to its development and conservation. In recent years, the need has developed for the Survey to provide data and technology to predict the impact of man's activities upon the water resource and the water environment. To accomplish its mission, the Geological Survey determines the source, quantity, quality, distribution, movement, and availability of both surface and ground water. This work includes the assessment of the chemical, physical, and biological quality of water resources and its relation to various parts of the hydrologic cycle; research to improve the scientific basis of investigations and techniques; design and operation of a national water-data network; and publication of its investigations.

Texas↗
USGS1975

Basic ground-water data for the Moscow Basin, Idaho

The Moscow basin encompasses an area of 65 square miles (170 square kilometres) in Latah County and borders the Idaho Washington State line (fig. 1). The basin is along the eastern edge of the "Palouse Country" where the rolling Palouse hills merge with the low mountains of northern Idaho. It is drained by the South Fork Palouse River, Paradise Creek, and Missouri Flat Creek, and their headwater tributaries. All water supplies for the basin are derived from wells and springs. Virtually all large-capacity wells are owned by the City of Moscow and the University of Idaho. These wells are open to the basalt of the Columbia River Group and the interbedded sands in the Latah Formation (Stevens, 1960, p. 335; Jones and Ross, 1972, p. 12-13, fig. 4). Many domestic and a few commercial wells are also open to these same formations. Most of the City and University wells tap thick sections of these water-bearing formations. However, only about 25 percent of the total basin area is underlain by basalt. The approximate subsurface extent of the area underlain by basalt, as determined by well logs and geophysical data, is shown in figure 2. The purpose of this report is to present basic geologic and hydrologic data that are available in the basin. Included are a table of well records, well logs, a table of annual ground-water withdrawals, water levels in observation wells, a contour map showing the approximate elevation of the water-level in the upper series of basalt flows and interbedded sediments in the southern part of the area (fig. 2), and a bibliography of the more important reports pertaining to ground water in the area. More than 90 percent of the wells tapping basalt were visited, but only a representative number of wells tapping other rocks were visited. Data that may have become available after December 1972 are not given except for water-level measurements made in March 1973.

Idaho↗
USGS1991

Computer software for converting ground-water and water-quality data from the National Water Information System for use in a geographic information system

A geographic information system (GIS) is computer software that provides the capabilities to rapidly display and analyze spatially referenced data. To use a GIS efficiently, software is needed that provides a link between existing spatially referenced data-base systems and the GIS. The U.S. Geological Survey (USGS) stores large amounts of spatially referenced hydrologic data in computerized data-base systems. Currently, these data-base systems are physically located on computers that are installed in many USGS offices nationwide. This report describes software that can be used quickly and easily to convert site-description and water-quality data from these data-base systems to the GIS that is used by the USGS. The software described in this report is designed to be used with the same hardware and software that is available to most USGS personnel.

Water-Resources Investigations Report↗
USGS2015

Estimation of unaltered daily mean streamflow at ungaged streams of New York, excluding Long Island, water years 1961-2010

The lakes, rivers, and streams of New York State provide an essential water resource for the State. The information provided by time series hydrologic data is essential to understanding ways to promote healthy instream ecology and to strengthen the scientific basis for sound water management decision making in New York. The U.S. Geological Survey, in cooperation with The Nature Conservancy and the New York State Energy Research and Development Authority, has developed the New York Streamflow Estimation Tool to estimate a daily mean hydrograph for the period from October 1, 1960, to September 30, 2010, at ungaged locations across the State. The New York Streamflow Estimation Tool produces a complete estimated daily mean time series from which daily flow statistics can be estimated. In addition, the New York Streamflow Estimation Tool provides a means for quantitative flow assessments at ungaged locations that can be used to address the objectives of the Clean Water Act—to restore and maintain the chemical, physical, and biological integrity of the Nation’s waters. The New York Streamflow Estimation Tool uses data from the U.S. Geological Survey streamflow network for selected streamgages in New York (excluding Long Island) and surrounding States with shared hydrologic boundaries, and physical and climate basin characteristics to estimate the natural unaltered streamflow at ungaged stream locations. The unaltered streamflow is representative of flows that are minimally altered by regulation, diversion, or mining, and other anthropogenic activities. With the streamflow network data, flow-duration exceedance probability equations were developed to estimate unaltered streamflow exceedance probabilities at an ungaged location using a methodology that equates streamflow as a percentile from a flow-duration curve for a particular day at a hydrologically similar reference streamgage with streamflow as a percentile from the flow-duration curve for the same day at an ungaged location. The reference streamgage is selected using map correlation, a geostatistical method in which variogram models are developed that correlate streamflow at one streamgage with streamflows at all other locations in the study area. Regression equations used to predict 17 flow-duration exceedance probabilities were developed to estimate the flow-duration curves at ungaged locations for New York using geographic information system-derived basin characteristics. A graphical user interface, with an integrated spreadsheet summary report, has been developed to estimate and display the daily mean streamflows and statistics and to evaluate different water management or water withdrawal scenarios with the estimated monthly data. This package of regression equations, U.S. Geological Survey streamgage data, and spreadsheet application produces an interactive tool to estimate an unaltered daily streamflow hydrograph and streamflow statistics at ungaged sites in New York. Among other uses, the New York Streamflow Estimation Tool can assist water managers with permitting water withdrawals, implementing habitat protection, estimating contaminant loads, or determining the potential affect from chemical spills.

New York↗
USGS2025

Water-resources inventory and assessment at Katahdin Woods and Waters National Monument

The U.S. Geological Survey, in cooperation with the National Park Service, prepared a water-resources inventory and assessment for Katahdin Woods and Waters National Monument (KAWW). This compilation includes published and publicly accessible hydrologic data and resource assessments of streams, rivers, ponds, lakes, wetlands, vernal pools, and groundwater in and near KAWW. It also includes reports and datasets summarizing attributes of KAWW’s hydrologic infrastructure, such as stream crossings, dams, wastewater discharge plants, groundwater monitoring wells, and U.S. Geological Survey streamflow-gaging stations. Descriptions of data and details of current limitations in available datasets are included. Wetland, groundwater, streamflow, and water-quality information are all limited. Hydrography data are available; however, there are limited ground-truth data. Accurate streamlines within KAWW were developed from light detection and ranging (lidar) as a part of this work. Hydrologic infrastructure information is available from multiple sources; however, differences exist among the datasets. Datasets are summarized in appendix 1.

Maine↗
USGS2021

Post-wildfire hydrologic recovery in Mediterranean climates: A systematic review and case study to identify current knowledge and opportunities

Post-fire hydrologic research typically focuses on the first few years after a wildfire , leading to substantial uncertainty regarding the longevity of impacts. The time needed for hydrologic function to return to pre-fire conditions is critical information for post-fire land and water management decisions. This is particularly true in Mediterranean climates , where water is scarce and in high demand, and the severity and area burned by wildfires are increasing. In part, uncertainty about hydrologic recovery is due to lack of a consistent definition or interpretation of what constitutes “recovery.” Here, we systematically reviewed empirical studies from Mediterranean climates with at least three years of post-fire hydrologic data with the objectives of (a) assessing the recovery period, (b) identifying a definition of post-fire hydrologic recovery, (c) demonstrating a simple analytical approach to aid in assessment of recovery, and (d) outlining research needs and opportunities to better quantify post-fire recovery. We assessed the hydrologic effects reported in 38 sites that were monitored for 3–20 years. Eighteen sites were considered recovered within seven years; however, the recovery time was inconsistent across sites and was not related to location, response variable, or study design. The likelihood of recovery within the study period also decreased with increasing proportion of the watershed area burned. Importantly, we have also proposed a standardized definition and an approach to quantifying hydrologic recovery that may facilitate cross-study comparisons and a deeper understanding of recovery. Specifically, we propose hydrologic recovery has occurred when a specific post-fire hydrologic function or condition of interest returns to the 95% confidence interval of the pre-fire condition. In support of this definition, we have demonstrated applying this simple approach to assess recovery and presented future research topics to improve our understanding of long-term post-fire catchment responses. In addition to the need for more studies that quantify hydrologic responses farther into the post-fire period, understanding post-fire changes in soil structural and hydraulic properties through time will improve our mechanistic understanding of post-fire hydrologic responses and recovery.

Journal of Hydrology↗
USGS1990

Precipitation Data for the Mount St. Helens Area, Washington--1981-86

This report is a compilation of precipitation data from U.S. Geological Survey telemetered 'Early Flood Warning' sites near Mount St. Helens, Washington, and from telemetered hydrologic data sites in the Toutle River and Muddy River basins for the years 1981-86. It also includes precipitation data for 1981-86 from non-telemetered recording rain gages established near the debris-avalanche blockages of Spirit Lake, Coldwater Lake, and Castle Lake. Daily values (midnight to midnight) are listed by station and calendar year for 32 sites. Hourly data, where available, are presented for the storm that generated the highest peak discharge in the North Fork Toutle River each water year. Instrumentation includes 25 tipping-bucket, and 7 weighing-bucket rain gages all without windshields. The seven sites with weighing-bucket gages were the only U.S. Geological Survey sites at which snowfall was measured. Additional snowfall measurements for the same time period in the Mount St. Helens area were collected by the National Weather Service, the U.s. Soil Conservation Service, and the U.S. Army Corps of Engineers and also are presented in this report.

Open-File Report↗
USGS2008

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↗
USGS1992

Records of wells in sandstone and alluvial aquifers and chemical data for water from selected wells in the Navajo aquifer in the vicinity of the greater Aneth Oil Field, San Juan County, Utah

This report contains hydrologic data for wells finished in sandstone and alluvial aquifers in southeastern San Juan County, Utah, and chemical data for water from selected wells in the Navajo aquifer. Temperature, specific conductance, pH, and discharge data from 1989-91 for water from selected wells in all aquifers are also presented. Data presented in this report were compiled from previously published reports (Goode, 1958; Sumsion, 1975; Avery, 1986; Kimball, 1987; Howells, 1990); data bases of the U.S. Geological Survey, the Navajo Tribe, the U.S. Bureau of Land Management, the Utah Division of Water Rights, and the Utah Division of Oil, Gas, and Mining; and from information obtained from oil companies in the Greater Aneth Oil Field. Results of investigations by Avery (1986) during 1982-83 indicated that water from many wells in the Navajo aquifer in the vicinity of the Greater Aneth Oil Field was moderately saline and that in some wells, salinity appeared to increase over time. The purpose of this study is to assess the physical extent and concentration of saline water in the Navajo and other aquifers in this area. The purpose of this report is to present available water-quality data for water from wells in the Navajo aquifer and present records for selected wells in the Navajo and other aquifers.

Utah↗
USGS2014

Numerical analysis of regional water levels to define aquifer hydrology

Two fundamental methods for studying aquifer hydrology are now in use. The first, applied many years ago, consists of detailed observation of aquifer inflow, outflow, and storage changes, and their variations in time. By analysis of these observations, estimates of the perennial recharge to the aquifer and other pertinent hydrologic data are obtained, all as gross characteristics of the aquifer. The need for greater detail gave rise to a second fundamental method: special field tests, such as pumping tests, by which the hydrologic coefficients could be measured in a comparatively short time. In order to evaluate properly the ability of an aquifer to serve as a source of perennial water supply, the geology and hydrology of the aquifer must be known in some detail over its entire area. The first method cannot supply the necessary detail in most cases, and the second method cannot ordinarily provide the needed areal coverage because of the lack of appropriate testing facilities. Thus an auxiliary third approach was sought which would combine the features of a simple data‐collection program with a final analysis yielding both adequate detail and areal coverage. A method designed to satisfy these requirements is described. Water‐level altitudes, usually observed in the course of more general ground‐water studies, are analyzed by numerical methods, using finite‐difference approximations of the basic differential equations which describe ground‐water flow. Analytical methods are given for nonsteady flow through homogeneous and nonhomogeneous aquifers. Both direct and statistical solutions are shown. The hydrologic factors are computed as functions of transmissibility, and for the nonhomogeneous aquifer the variations of transmissibility in space are computed also from the water‐level data. Knowledge of the absolute value of any one of the hydrologic factors at some location in the aquifer permits conversion of the computed functions to absolute terms for all the aquifer flow field studied.

Eos, Transactions, American Geophysical Union↗
USGS1993

Water-quality data for two surface coal mines reclaimed with alkaline waste or urban sewage sludge, Clarion County, Pennsylvania, May 1983 through November 1989

Water-quality and other hydrologic data for two surface coal mines in Clarion County, Pa., were collected during 1983-89 as part of studies conducted by the U.S. Geological Survey in cooperation with the Pennsylvania Department of Environmental Resources. Water samples were collected from streams, seeps, monitor wells, and lysimeters on a monthly basis to evaluate changes in water quality resulting from the addition of alkaline waste or urban sewage sludge to the reclaimed mine-spoil surface. The mines are about 3.5 miles apart and were mined for bituminous coal of the upper and lower Clarion seams of the Allegheny Group of Pennsylvanian age. The coal had high sulfur (greater than 2 weight percent) concentrations. Acidic mine drainage is present at both mines. At one mine, about 8 years after mining was completed, large quantities (greater than 400 tons per acre) of alkaline waste consisting of limestone and lime-kiln flue dust were applied on two 2.5-acre plots within the 65-acre mine area. Water-quality data for the alkaline-addition plots and surrounding area were collected for 1 year before and 3 years after application of the alkaline additives (May 1983-July 1987). Data collected for the alkaline-addition study include ground-water level, surface-water discharge rate, temperature, specific conductance, pH, and concentrations of alkalinity, acidity, sulfate, iron (total and ferrous), manganese, aluminum, calcium, and magnesium. At the other mine, about 3.5 years after mining was completed, urban sewage sludge was applied over 60 acres within the 150-acre mine area. Waterquality data for the sludge-addition study were collected for 3.5 years after the application of the sludge (June 1986-December 1989). Data collected for the sludge-addition study include the above constituents plus dissolved oxygen, redox potential (Eh), and concentrations of dissolved solids, phosphorus, nitrogen species, sulfide, chloride, silica, sodium, potassium, cyanide, arsenic, barium, boron, cadmium, chromium, copper, lead, mercury, molybdenum, nickel, selenium, strontium, and zinc. Climatic data, including monthly average temperature and cumulative precipitation, from a nearby weather station for the period January 1983 through December 1989 also are reported.

Open-File Report↗