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Stephen W. Wolcott

Publications and source records attributed to Stephen W. Wolcott.

7 recordsLinked to original sources

Graphical viewer for displaying locations and logs of selected wells and test holes in Putnam County, New York

Aquifers (water bearing geologic units) are the primary source of drinking water in most of Putnam County, N.Y. The principal sources of data used to define the geometry and hydraulic characteristics of aquifers are the logs of wells and test holes within the county. This report explains how to use a graphical viewer, available on the World Wide Web (http://ny.water.usgs.gov/pubs/of/of051198), to locate selected wells and test holes in Putnam County and display their logs.

Open-File Report

Simulation of a valley-fill aquifer system to delineate flow paths, contributing areas, and traveltime to wellfields in southwestern Broome County, New York

A valley-fill aquifer system that extends along a 14-mile reach of the Susquehanna River valley in southwestern Broome County, N.Y., is a major source of water supply to local municipalities and industries, but is highly susceptible to contamination from human activities. Protection of ground-water supplies requires accurate delineation of the areas that are the sources of water pumped by wells. A previously developed two-layer steady-state ground-water flow model of the aquifer system was upgraded with an improved method of simulating stream-aquifer interactions, then recalibrated and coupled to a particle-tracking program. Three-dimensional, ground-water flow modeling coupled with particle tracking is the most reliable method of simulating groundwater flow paths in multiaquifer systems such as this; it also allows delineation of contributing areas to well.elds. A primary advantage of three-dimensional particle-tracking analysis is that it shows the complexities of the flow paths in each aquifer. Model and particle tracking analyses indicate that groundwater frequently follows convoluted three-dimensional flow paths. The contributing areas of individual supply wells in this aquifer system each has a unique flow pattern and shape. Results of the model simulation indicate that recharge from precipitation, rivers, and tributaries contribute 35 percent, 29 percent, and 25 percent, respectively to the aquifer system and that pumpage from supply wells accounts for 67 percent of the discharge from the aquifer system. Particle-tracking results indicate that the simulated contributing areas to the 24 supply wells includes most of the valley floor.

New York

Computation of bedrock-aquifer recharge in northern Westchester County, New York, and chemical quality of water from selected bedrock wells

An empirical technique was used to calculate the recharge to bedrock aquifers in northern Westchester County. This method requires delineation of ground-water divides within the aquifer area and values for (1) the extent of till and exposed bedrock within the aquifer area, and (2) mean annual runoff. This report contains maps and data needed for calculation of recharge in any given area within the 165square-mile study area. Recharge was computed by this technique for a 93-square-mile part of the study area and used a ground-water-flow model to evaluate the reliability of the method. A two-layer, steady-state model of the selected area was calibrated. The area consists predominantly of bedrock overlain by small localized deposits of till and stratified drill Ground-water-level and streamflow data collected in mid-November 1987 were used for model calibration. The data set approximates average annual conditions. The model was calibrated from (1) estimates of recharge as computed through the empirical technique, and (2) a range of values for hydrologic properties derived from aquifer tests and published literature. Recharge values used for model simulation appear to be reasonable for average steady-state conditions. Water-quality data were collected from 53 selected bedrock wells throughout northern Westchester County to define the background ground-water quality. The constituents and properties for which samples were analyzed included major cations and anions, temperature, pH, specific conductance, and hardness. Results indicate little difference in water quality among the bedrock aquifers within the study area. Ground water is mainly the calcium-bicarbonate type and is moderately hard. Average concentrations of sodium, sulfate, chloride, nitrate, iron, and manganese were within acceptable limits established by the U.S. Environmental Protection Agency for domestic water supply.

Water-Resources Investigations Report

Selected ground-water data in the upper Mongaup River basin, Sullivan County, New York

A set of four adjoining 7.5-minute quadrangle sheets that together depict the upper Mongaup River Basin in Sullivan County , N.Y., at 1:24,000 scale show the location, well yield, depth, water use, ownership, and date of ownership of wells, test holes , and springs. Most wells that tap stratified-drift deposits have high yields (50 to 300 gal/min) and are used for public supply. Bedrock wells have smaller yields and are generally used for domestic supply. The data were compiled from a previous U.S. Geological Survey, countywide, groundwater resources report and from unpublished data. (USGS)

Open-File Report

Floods in Indiana, June-August 1979

This report documents rainstorms and resultant floods in central and southern Indiana during the summer of 1979. Major flooding was caused by three storms, one in June and two in July 1979, centered primarily in central and southern Indiana. Peak discharge exceeded the 100-year recurrence interval at 16 sites in this area. State Civil Defense officials estimated that almost 50-million dollars damage was attributable to the July floods. Hydrologic data have been tabulated for streamflow sites in the areas of flooding. Reservoir storage volumes, observation-well data, rainfall totals, and discharge hydrographs are presented to show the intensity and time of the storms and resultant floods. (USGS)

Indiana