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The average annual ground-water recharge to the Edwards aquifer in the San Antonio area, Texas, from 1934 through 1982, was 608,400 acre-feet. The recharge in 1982 was 417,700 acre-feet. 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 1982 was 786,400 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 453,100 acre-feet in 1982, which is the second highest discharge for the 1934-82 period of record.

Although water levels in many of the wells in the Edwards aquifer fluctuated near the midpoint between record high and low levels during the summer of 1982, 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. However, trace concentrations of organic compounds were detected in some of the analyses.