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R.D. Reeves

Publications and source records attributed to R.D. Reeves.

10 recordsLinked to original sources
USGS1984

Compilation of hydrologic data for the Edwards Aquifer, San Antonio area, Texas, 1981, with 1934-81 summary

The average annual ground-water recharge to the Edwards aquifer in the San Antonio area, Texas, from 1934 through 1981, was 612,400 acre-feet. The recharge in 1981 was 1,448,400 acre-feet, which is the third highest annual recharge since 1934. A maximum annual recharge of 1,711,200 acre-feet occurred in 1958, and a minimum annual recharge of 43,700 acre-feet occurred in 1956. The calculated annual discharge by wells and springs in 1981 was 794,400 acre-feet. Annual discharge by wells and springs ranged from a maximum of 960,900 acre-feet in 1977 to a minimum of 388,800 acre-feet in 1955. The annual discharge by wells was 387,100 acre-feet in 1981. Although water levels in many of the wells in the Edwards aquifer fluctuated near the midpoint between record high and low levels during the first 5 months of 1981, the volume of ground water in storage in the aquifer was above average for most of the year. Analyses of water samples from 56 wells and 3 springs show that the water is of a significantly better quality than the level established for public water systems.

Texas↗
USGS1983

Streamflow losses along the Balcones Fault Zone, Nueces River basin, Texas

An investigation was conducted to quantify and to determine distribution of streamflow losses and gains that occur during sustained flow conditions in the Balcones Fault Zone of the Nueces River basin. The streams studied include the West Nueces, Nueces, Dry Frio, Frio, and Sabinal Rivers, and Seco, Hondo, and Verde Creeks. Streamflow measurements made during the recession of storm flows identified direct recharge to outcrops of the Edwards aquifer and related limestones that ranged from as high as 393 cubic feet per second for the Dry Frio River to as low as 42 cubic feet per second for the Sabinal River. Recharge to outcrops of the Buda Limestone, Eagle Ford Shale, and Austin Group also eventually reaches the Edwards aquifer, and measurements identified losses to these formations ranging from as high as 174 cubic feet per second for the Frio River to near zero for Verde Creek. Statistical evaluations of historical daily flow records for the streams that have gaging stations upstream and downstream from the recharge zone provided mathematical relationships that expressed downstream flow in terms of other significant parameters. For each stream, flow entering the recharge zone is most significant in defining downstream flow; for some streams, antecedent flows at the upstream site and ground-water levels are also significantly related to downstream flow. The analyses also determined the discharges required upstream from the recharge zone to sustain flow downstream from that zone. These discharges ranged from 355 cubic feet per second for the combined Frio and Dry Frio Rivers to 33 cubic feet per second for the Nueces River. The entire flows of lesser magnitude are generally lost to recharge to the aquifer.

Texas↗
USGS1976

Chemical and bacteriological quality of water at selected sites in the San Antonio area, Texas, August 1968-January 1975

Urban development on or adjacent to the recharge zone of the Edwards aquifer is causing concern about the possible pollution of ground water in the aquifer, which is the principal source of water supply for the San Antonio area. Water-quality data for many wells and springs and for selected sites on streams that cross the recharge zone of the aquifer are being collected to provide background information and to detect any current pollution of ground water in the area. Water from the Edwards aquifer is very hard and of the calcium bicarbonate type. The concentrations of dissolved solids in samples from wells and springs ranged from about 200 to 470 mg/1 (milligrams per liter); the chloride and sulfate concentrations ranged from 6.5 to 62 mg/1 and from 0.0 to 65 mg/1, respectively. The nitrate and phosphate contents of the ground water ranged from 0.0 to 15 mg/1 and from 0.00 to 0. 37 mg/1. The concentrations of these and other constituents show that the chemical quality of water in the Edwards aquifer has not been degraded significantly by domestic, industrial, or agricultural effluents. However, variations in the number of coliforms, the concentrations of nitrate and phosphate, and the presence of fecal coliforms and fecal streptococci in samples from some wells show that fecal pollution is reaching the aquifer. Most of these wells, which are located in or just downdip from the recharge zone, are poorly sealed or inadequately cased. The areal variation in the locations of these wells indicates that pollution of ground water in the aquifer is very localized. Prllution results principally from runoff from the land surface and from effluent from septic tanks which enters the aquifer through fractures in the recharge zone or which infiltrates through the thin soil into poorly sealed or inadequately cased wells in or adjacent to the recharge zone. Trace amounts of several pesticides have been detected in samples from two wells in the San Antonio area. Field investigations showed the source of pesticides in these wells to be. surface drainage that entered the wellbores. Water-quality data collected at sites on streams that cross the recharge zone of the Edwards aquifer show the chemical composition of surface water to be very similar to that of ground water in the area. Water in most streams is very hard and of the calcium bicarbonate type. Limited data on the bacteriological quality show that coliforms were present at each of the site sampled and that fecal coliforms and fecal streptococci were present at most sites. Although the number of these bacteria varied greatly in both time and place, their density in samples from most sites were low for untreated surface water.

Texas↗
USGS1970

Geology and water quality at selected locations in the San Antonio area, Texas, Progress Report, 1969

The Edwards aquifer is the principal source of water supply for the San Antonio area. Increasing urban development on or adjacent to the recharge area of the aquifer is causing great concern because of possible pollution of the ground water. A detailed map of the surface geology has been prepared for areas where the greatest threat of pollution exists. Water-quality data are being collected throughout the San Antonio area to provide background reference information and to detect any current pollution of the ground water in the Edwards and associated limestones. Mapping of the surface geology will continue in areas where waste waters may be recharging the aquifer. Water-quality data will be collected at additional sites, and some sites will be resampled where pollution may be occurring or where more background data are needed.

Open-File Report↗