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L. D. Arihood

Publications and source records attributed to L. D. Arihood.

11 recordsLinked to original sources
USGS1998

Geohydrology and simulated ground-water flow in northwestern Elkhart County, Indiana

In 1994, the U.S. Geological Survey, in cooperation with the U.S. Environmental Protection Agency and the City of Elkhart, developed a ground-water model of the Elkhart, Indiana, area to determine the avail-ability and source of water at potential new well fields. The modeled area covered 190 square miles of northwestern Elkhart County and a small part of southern Michigan. Three Superfund sites and several other sites in this area are undergoing environmental cleanup. The model would be used to guide the location of well fields so that Superfund sites and environmental cleanup areas would not be within recharge areas for the well fields. The City of Elkhart obtains its water supply from two aquifers separated by a generally continuous confining unit. The upper aquifer is composed primarily of sand and gravel of glacial origin. Thickness of the upper aquifer ranges from 0 to 116 feet and averages 47 feet. The lower aquifer is composed of sand and gravel with interbedded lenses of silt and clay. Thickness of the lower aquifer ranges from 1 to 335 feet and averages 35 feet. The intervening confining unit is composed of silt and clay with interbedded sand and gravel; the confining unit ranges from 0 to 177 feet, with an average thickness of 27 feet. Flow through the aquifers is generally horizontal vertically downward from the upper aquifer, through the confining unit, and into the lower aquifer, except where flow is vertically upward at the St. Joseph River and other large streams. The hydraulic characteristics of the aquifers and confining unit were estimated by analyzing aquifer-test data from well drillers? logs and by calibration of the model. The horizontal hydraulic conductivity of the upper aquifer is 170 feet per day within about 1 mile of the St. Joseph and Elkhart Rivers and 370 feet per day at distances greater than about 1 mile. The horizontal hydraulic conductivity of the lower aquifer is 370 feet per day throughout the modeled area, with the exception of an area near the center of the modeled area where the horizontal hydraulic conductivity is 170 feet per day. Transmissivity of the lower aquifer increases generally from southwest to northeast; transmissivity values range from near 0 where the lower aquifer is absent to 57,000 square feet per day and average about 8,100 square feet per day. The vertical hydraulic conductivity of the confining unit is 0.07 feet per day; the vertical conductivity of the streambeds commonly is 1.0 foot per day and ranges from 0.05 foot per day to 50 feet per day. The areal recharge rate to the outwash deposits was determined by a base-flow separation technique to be 16 inches per year, and the areal recharge rate to the till was assumed to be 4 inches per year. A two-layer digital model was used to simulate flow in the ground-water system. The model was calibrated on the basis of historical water-use data, water-level records, and gain/loss data for streams during May and June 1979. The model was recalibrated with water-use data and water-level records from 1988. For 1979 data, 49 percent of the inflow to the model area is from precipitation and 46 percent is ground-water inflow across the model boundaries. Most of the ground-water inflow across the model boundary is from the north and east, which corresponds to high values of transmissivity?as high as 57,000 feet squared per day?in the model layers in the northern and eastern areas. Eighty-two percent of the ground-water discharge is to the streams; 5 percent of the ground-water discharge is to wells. Source areas and flow paths to the City of Elkhart public well fields are affected by the location of streams and the geology in the area. Flow to the North Well Field originates north-west of the well field, forms relatively straight flow paths, and moves southeast toward the well field and the St. Joseph River. Flow to the South Well Field begins mostly in the out-wash along Yellow Creek south of the well field, moves northward, and t

Indiana↗
USGS1998

Geohydrology and quality of ground water in unconsolidated aquifers near South Bend, Indiana

Introduction The water supply for the City of South Bend, Indiana, and much of surrounding St. Joseph County is provided by 36 municipal and community well fields. Some of these well fields are located near known or potential sources of ground-water contamination that could affect ground-water supplies in the near future. As population and industry grow, it will be necessary to find additional sources of water and determine their quantity and quality. Geohydrologic and water-quality data are available to identify areas for developing additional ground-water supplies, but these data have not been compiled into one source accessible to area water-resource managers. This report presents a compilation of these geohydrologic and water-quality data for the ground-water system in and near South Bend that can be used to identify potentially favorable areas for developing additional ground-water supplies for municipal use. The data were compiled by the U.S. Geological Survey, in cooperation with the South Bend Water Works, for a study area of approximately 535 square miles that includes all of St. Joseph County and the eastern part of La Porte County. A map format has been used to facilitate comparison between geohydrologic and water-quality information. Previously published geologic maps and cross sections describe the geologic setting and aquifer deposits of the study area, the hydrogeology of northeastern St. Joseph County, and the ground-water quality of northeastern St. Joseph County. Beaty (1990) and Clendenon and Beaty (1987) produced water-resource-availability reports for the St. Joseph and Kankakee River Basins.

Indiana↗
USGS1996

Hydrogeology and simulated ground-water flow through the unconsolidated aquifers of northeastern St. Joseph County, Indiana

The U.S. Geological Survey investigated ground-water resources of northeastern St. Joseph County, Indiana, during 1990-93. The investigation included field measurements of water levels and numerical models of ground-water flow. This report documents results of that work and includes descriptions of (1) hydrogeologic framework, (2) water levels, (3) model sensitivity to variations in hydrogeologic parameters, (4) simulated aquifer response to increased ground-water withdrawals, (5) recharge areas for significant water- withdrawal facilities, (6) flow paths and discharge points for ground-water solutes originating beneath known contamination sites. Water-level data indicated (1) regional ground- water flow towards the St. Joseph River, (2) depth to water is small in the St. Joseph aquifer system compared to that in the Hilltop and Nappanee aquifer systems, (3) water levels in deep and shallow parts of the aquifer system are not equal where a confining unit is present. Model results indicate increasing withdrawals by 50 percent at significant water-withdrawal facilities would cause drawdowns less than 6 feet in the 1/4-square-mile area surrounding pumping sites. The response of Juday Creek and the St. Joseph River to increased ground-water pumpage is reductions of ground-water contribution to streamflow of 23 percent and 6 percent, respectively. Particle-tracking analyses indicate flow paths for solutes originating beneath known contamination sites may pass near to, or be intercepted by, significant water-withdrawal facilities. Most particles are discharged to the St. Joseph River but some may be discharged to Juday Creek.

Indiana↗
USGS1995

Geohydrology and simulation of ground-water flow in the aquifer system near Calvert City, Kentucky

The U.S. Geological Survey, in cooperation with the Kentucky Natural Resources and Environmental Protection Cabinet, constructed a two-dimensional, steady-state ground-water-flow model to estimate hydraulic properties, contributing areas to discharge boundaries, and the average linear velocity at selected locations in an aquifer system near Calvert City, Ky. Nonlinear regression was used to estimate values of model parameters and the reliability of the parameter estimates. The regression minimizes the weighted difference between observed and calculated hydraulic heads and rates of flow. The calibrated model generally was better than alternative models considered, and although adding transmissive faults in the bedrock produced a slightly better model, fault transmissivity was not estimated reliably. The average transmissivity of the aquifer was 20,000 feet squared per day. Recharge to two outcrop areas, the McNairy Formation of Cretaceous age and the alluvium of Quaternary age, were 0.00269 feet per day (11.8 inches per year) and 0.000484 feet per day (2.1 inches per year), respectively. Contributing areas to wells at the Calvert City Water Company in 1992 did not include the Calvert City Industrial Complex. Since completing the fieldwork for this study in 1992, the Calvert City Water Company discontinued use of their wells and began withdrawing water from new wells that were located 4.5 miles east-southeast of the previous location; the contributing area moved farther from the industrial complex. The extent of the alluvium contributing water to wells was limited by the overlying lacustrine deposits. The average linear ground-water velocity at the industrial complex ranged from 0.90 feet per day to 4.47 feet per day with a mean of 1.98 feet per day.

Water-Resources Investigations Report↗
USGS1994

Geohydrology and simulated ground-water flow in an irrigated area of northwestern Indiana

Water for irrigation in parts of Newton and Jasper Counties and adjacent areas of northwestern Indiana is pumped mostly from the carbonate- bedrock aquifer that underlies glacial drift. To help in managing the ground-water resources of the area, a three-dimensional ground-water model was developed and tested with hydrologic data collected during 1986 and 1988. Two major aquifers and a confining unit were identified. The surficial unconfined outwash aquifer consists of sand and some gravel. Saturated thickness averages about 30 feet. Estimated values of horizontal hydraulic conductivity and storage coefficient are 350 feet per day and 0.07, respectively. The generally continuous confining unit beneath the outwash aquifer is composed predominantly of till and lacustrine silt and clay and is 0 to 125 feet thick. The carbonate-bedrock aquifer is composed of Silurian and Devonian dolomitic limestone; dolomite and has a median transmissivity of 2,000 feet squared per day. A nine-layer digital model was developed to simulate flow in the ground-water system. The mean absolute errors for simulated water levels in the bedrock aquifer ranged from 5 to 7 feet for two recent periods of irrigation. The component of the flow system that most affects water-level drawdowns in the bedrock aquifer is the confining unit which controls the rate of leakage to the bedrock aquifer. The model is most accurate in areas for which data for confining-unit thickness and bedrock water levels are available.

Indiana↗
USGS1991

Sedimentation in Versailles Lake, Ripley County, southeastern Indiana, 1956-88

Sedimentation has affected the storage capacity and surface area of Versailles Lake. The lake was constructed by damming Laughery Creek in 1956. At the dam, the drainage area of Laughery Creek is 168 square miles. Locations where the largest amount of sediment has accumulated for the 32-year period 1956-88, are in the upper end of the lake where Laughery Creek enters and in the middle part of the lake; however, sediment has also accumulated in the rest of the lake. The surface area of the lake for 1956 was 10,400,000 square feet (239 acres) and for 1988 was 9,700,000 square feet (223 acres). In 1956, the volume of water in Versailles Lake was 115,000,000 cubic feet; in 1988, the volume was 73,400,000 cubic feet. The amount of sediment accumulation in the lake during 1956-88 was 41,600,000 cubic feet. In 1988, the volume of water remaining in the lake was 63.8 percent of the 1956 volume; 36.2 percent of the 1956 lake volume had filled with sediment. The annual rate of sediment accumulation in the lake during 1956-88 was 1,300,000 cubic feet per year. Potential decreases in the storage capacity of Versailles Lake for the 32-year period 1989-2020 were estimated. The percentage volume of water in the lake in 2020 is expected to be 28 percent of the 1956 volume; 72 percent of the lake is expected to be filled with sediment. Physiographic data indicate no distinct source areas in the drainage basin of Laughery Creek that are contributing unusually large amounts of sediment to Versailles Lake.

Indiana↗
USGS1989

Preliminary analysis of the shallow ground-water system in the vicinity of the Grand Calumet River/Indiana Harbor Canal, northwestern Indiana

The shallow groundwater system in the vicinity of the Grand Calumet River-Indiana Harbor Canal, Indiana was analyzed from June 1985 to May 1986. This analysis was done to obtain detailed information about the physical characteristics of the Calumet aquifer and the shallow groundwater flow system. 36 shallow wells were installed and sediment samples were collected at 26 sites. Water level measurements were made in 45 wells. Data indicate that the aquifer consists of fine-grained to medium-grained sand, locally overlain by slag fill. Aquifer thickness is 0 to 65 ft. This aquifer is underlain by about 100 ft of glacial till and lacustrine clay that overlies carbonate bedrock of Silurian age. Broad, low-relief water table mounds occur between the major surface water drains. The crests of these mounds form major east-west-trending water table divides. Northwest of the Indiana Harbor Canal (IHC), a narrow water table ridge parallels the Lake Michigan shoreline and connects to a somewhat circular, low mound northwest of the IHC. Shallow groundwater generally flows from these water table mounds to the major streams or to Lake Michigan. Groundwater also flows to small ditches, wetlands, and sewer lines. Stream/aquifer relations along the Grand Calumet River/IHC were quite complex. Digital model simulations of a conceptual north-south section near the middle of the study area indicate that discharge of groundwater to small ditches and leaky sewer lines has lowered the water table by several ft from predevelopment levels. Simulations also indicate that downward leakage to the bedrock may have contributed to the decline in the water table.

Indiana↗
USGS1989

Evaluation of a watershed model to simulate sediment transport in a small agricultural watershed in Indiana

The streamflow and sediment components of the watershed model, ' Hydrologic Simulation Program-Fortran ', were evaluated using 2 years and 9 months of data from a 2.7-sq mi agricultural watershed in Indiana. Hydrographs of simulated sediment concentration generally have smaller peaks and longer recessions than do hydrographs of measured data. The attenuation of simulated peaks was partly caused by difficulties in designing a representative channel system. Simulated surface runoff during low-intensity rainfall was greater than measured surface runoff; this caused an overestimation of sediment concentration and discharge. Rainfalls of low intensity were mostly absorbed by the soil, but the model predicted that the amount of surface runoff from such storms would be large. The overly large volume of simulated surface runoff transported more sediment than actually occurred. The mean absolute error of mean sediment concentrations during storms is 45% of the measured average concentration. The error resulted from a combination of error in recording streamflow and rainfall, in simulating streamflows, and in simulating sedimentation processes. The largest percent errors are associated with simulated maximum streamflows and average sediment discharges. The root-mean-square errors are 93 and 102% of the measured maximum streamflow and average sediment discharges. (USGS)

Indiana↗
USGS1986

Description of sediment data collected by the U.S. Geological Survey in small watersheds in coal-mining areas of the eastern United States, 1980-84

Hydrologic data were collected by the U.S. Geological Survey from 20 small watersheds in the surface-mining areas of the eastern United States from 1980 through 1984 as part of the Survey1 s coal-hydrology program. Each data set includes sediment-concentration, streamflow, and precipitation data collected at 5- or 15-minute intervals. One reason for collecting the data was to test the sediment component of a watershed model. However, adequate testing requires reliable calibration data collected at several points during the rise and fall of hydrographs of several storms. Therefore, the quantity and quality of the data sets needed to be described to determine which sets could be used to test a model adequately. The data sets are described in a table that presents information about watershed characteristics, period of record, and amount of useful sediment data. Also, similar data sets collected by 10 Survey project offices during other Survey programs are described in a similar table.

Open-File Report↗
USGS1984

Ground-water resources of the White River basin, Randolph County, Indiana

The two major aquifer systems in Randolph County, Indiana are sand and gravel and bedrock (limestone, dolomite, and shale of Silurian to Odovician age). The average thickness of the sands and gravels is 15 ft, and the aquifers are areally discontinuous. The bedrock aquifer underlies the entire study area and is estimated to be 150 ft in thickness. Six pumping plans simulated in the two systems by a five-layer, digital, ground-water-flow model provide data for an assessment of the water-yielding potential of the systems. The model indicates that as much as 2.5 million gallons per day can be pumped from the aquifers at some locations. This and similar rates of pumping may cause drawdown greater than 5 feet in 10 to 50 percent of the study area. About half the stream reaches were reduced in flow by more than 10 percent by the simulated pumping. However, reaches where discharge exceeded more than 2 cubic feet per second were not affected to this degree. (USGS)

Indiana↗