Relation of precipitation to annual ground-water recharge in the Edwards Aquifer, San Antonio area, Texas

Abstract

Annual recharge data obtained from historical records and mean-annual precipitation data computed from rainfall records were used to develop simple linear-regression equations for use in estimating annual recharge for seven subbasins in the San Antonio area. Adjustments were made to the precipitation parameter to account for the effects of year-end storms. The standard errors of estimate of the regression equations ranged from 26 percent for the Blanco River basin to 45 percent for the area between the Sabinal and Medina River basins.Annual-recharge estimates computed by use of the regression equations compared favorably with estimates made on the basis of observed streamflow and precipitation data.The report includes a brief review of the geology and hydrology of the Edwards aquifer, a discussion of the preparation and evaluation of the precipitation data used in the regression analyses, and a brief summary of the method previously used to estimate recharge.

Geochronology of late Pleistocene to Holocene speleothemsfrom central Texas: Implications for regional paleoclimate

“…Rainfall, which may vary significantly from year to year, is the primary source of aquifer recharge. Recharge is predominantly via losing streams as they cross the Balcones fault zone (Puente, 1975). Natural discharge occurs at springs within the fault zone.…”

Climate elasticity assessment on groundwater recharge to the Edwards Balcones Fault Zone Aquifer, United States

“…May and June have the highest recharge, followed by September and October (Figure 2d), showing a similar pattern to the monthly precipitation (Figure 2a). It should be noted that the basin boundaries defined in the Puente (1978) for recharge estimation are slightly different than the basin boundaries shown in Figure 1, particularly the SabMed basin and the Medina basin. The difference in basin boundaries is negligible because instead of volumetric recharge (acre‐feet), the area‐normalized recharge depth (mm) is used.…”

“…Estimates of groundwater recharge to the Edwards BFZA are made by the USGS in cooperation with the Edwards Aquifer Authority (Puente, 1978; Slattery, 2020). In this study, the dataset of monthly groundwater recharge (1934–2019) estimated by the USGS is used (Slattery, 2020).…”

“…In this study, the dataset of monthly groundwater recharge (1934–2019) estimated by the USGS is used (Slattery, 2020). The USGS method of estimating recharge is based on a water balance equation assuming that recharge within a basin is the difference between measured streamflow above and below the infiltration area (recharge zone, Figure 1) of the aquifer plus the estimated runoff (Puente, 1978). Estimates of groundwater recharge are made for each individual basin within the study area except the Guadalupe basin.…”

“…Estimates of groundwater recharge are made for each individual basin within the study area except the Guadalupe basin. Puente (1978) speculated that although the Guadalupe River crosses the recharge zone of the Edwards BFZA, it may not contribute recharge in significant quantities. Thus, no recharge in the Guadalupe basin is estimated.…”