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Robert C. Prill

Publications and source records attributed to Robert C. Prill.

5 recordsLinked to original sources
USGS1978

Ponding-test procedure for assessing the infiltration capacity of storm-water basins, Nassau County, New York

A procedure to obtain field data for assessing performance of storm-water basins having high infiltration rates is described. The basin selected is divided into test plots, and treated municipal water from a fire hydrant is ponded to the desired depth so that infiltration rates and flow patterns in the unsaturated zone can be determined by standard methods. The study was made at a storm-water basin excavated in glacial outwash deposits in Nassau County, Long Island, N.Y. in 1971-72. The types of interpretations and evaluations that can be made from test data are described, and applications of the procedure as well as guidelines for developing a similar testing program are given. Observations of special significance were: (1) Infiltration rate of the basin at low water stage is about 1.5 feet per hour but increases with increased water level; (2) flow through the unsaturated zone is essentially vertical; (3) infiltration rate is controlled by a surface stratum --in this case a gravelly, sandy loam; and (4) the position of the water table has little effect on infiltration rate provided it is below the lower boundary of the controlling zone. These observations can be used in evaluating a storm-water basin's suitability for supplemental recharge with treated wastewater, in comparing procedures for increasing a basin's infiltration capacity, or in the design of new storm-water basin systems.

Water Supply Paper↗
USGS1977

Analysis of the recharge potential of storm-water basins on Long Island, New York

Many of the more than 2,200 storm-water basins on Long Island, N.Y., are potential sites for infiltration of large volumes of reclaimed water (highly treated domestic and industrial sewage). By use of a finite-difference method of calculation, changes in basin storage during idealized high-intensity storms were determined for the North Massapequa basin, a typical basin on Long Island. Calculations for a 100- year storm, in which a runoff coefficient of 20 percent was used but in which infiltration rate, storm intensity, storm duration, and return period were varied, indicate that this test basin would not overflow even if the infiltration rate declined from its present 1.5 feet per hour (0.46 meter per hour) to about 0.03 ft/h (0.009 m/h). The large reserve capacity of the test basin and similar basins on Long Island demonstrates the feasibility of using storm-water basins for infiltration of a supplemental water supply (supplemental recharge). If reclaimed water were ponded to a depth of 4 ft (1.2 m) in the test basin and if water application were alternated for equal periods between the test basin and a nearby basin with similar characteristics, the volume of infiltration would be slightly more than two million gallons per day (0.09 cubic meters per second) at an infiltration rate of 1.5 ft/h (0.46 m/h). With supplemental recharge, 60 percent of available storage capacity would be used during a 10-yr storm, and 80 percent would be used during a 100-yr storm, using a runoff coefficient of 20 percent.

New York↗
USGS1973

Flow characteristics of a subsurface-controlled recharge basin on Long Island, New York

Ponding studies at the Woodbury recharge basin on Long Island, N.Y., show that the principal zones controlling infiltration are a surface-loam stratum and an intermediate gravelly, sandy loam stratum. The saturated hydraulic conductivities of these strata are 0.90 and 0.1 ft per day, respectively. The surface loam acts as the principal zone controlling infiltration until a perched ground-water mound develops above the intermediate gravelly, sandy loam and extends to the bottom of the surface loam; then the intermediate gravelly, sandy loam becomes the principal infiltration controlling zone. Infiltration rates at 15.6° Celsius are 1.4 ft per day when the surface loam is acting as the principal controlling zone and 0.5 ft per day when the intermediate gravelly, sandy loam is acting as the principal controlling zone. Projections of the probable infiltration rates associated with both the partial and the complete removal of the surface-loam stratum show that if recharge continues for several days total infiltration would not be greatly different whether or not the loam stratum is completely removed. The principal advantage of completely removing the surface-loam stratum is the resulting greater infiltration capacity during the early stages of ponding. This advantage is offset by potential problems associated with more intensive clogging of the subsurface controlling zone.

New York↗
USGS1965

Specific yield - laboratory experiments showing the effect of time on column drainage

The increasing use of ground water from many major aquifers in the United States has required a more thorough understanding of gravity drainage, or specific yield. This report describes one phase of specific yield research by the U.S. Geological Survey's Hydrologic Laboratory in cooperation with the California Department of Water Resources. An earlier phase of the research concentrated on the final distribution of moisture retained after drainage of saturated columns of porous media. This report presents the phase that concentrated on the distribution of moisture retained in similar columns after drainage for various periods of time. Five columns, about 4 cm in diameter by 170 cm long, were packed with homogenous sand of very fine, medium, and coarse sizes, and one column was packed with alternating layers of coarse and medium sand. The very fine materials were more uniform in size range than were the medium materials. As the saturated columns drained, tensiometers installed throughout the length recorded changes in moisture tension. The relation of tension to moisture content, determined for each of the materials, was then used to convert the tension readings to moisture content. Data were then available on the distribution of retained moisture for different periods of drainage from 1 to 148 hours. Data also are presented on the final distribution of moisture content by weight and volume and on the degree of saturation. The final zone of capillary saturation was approximately 12 cm for coarse sand, 13 cm for medium sand, and 52 cm for very fine sand. The data showed these zones were 92 to 100 percent saturated. Most of the outflow from the columns occurred in the earlier hours of drainage--90 percent in 1 hour for the coarse materials, 50 percent for the medium, and 60 percent for the very fine. Although the largest percentage of the specific yield was reached during the early hours of drainage, this study amply demonstrates that a very long time would be required to reach drainage equilibrium. In the layered columns the middle (medium sand) layer functioned as a hanging water column accelerating the drainage of the overlying coarse-sand layer. After the middle layer started to drain, the moisture distribution as retained in all three layers showed trends similar to that obtained when the same materials were tested in homogenous columns.

Water Supply Paper↗