Water Watch : Water Basin Stores

Orange County has a vast underground basin that contaians water used to supplement imported water during a drought. In 1977, at the end of the last drought, the ground-water basin was at 240,000 acre feet above the level recorded in 1956. The year 1956 is used as a baseline because it was the historical low point.

How does Orange County stand now, compared to 1977? It’s better off, but not by much. During the 1986-90 period, the amount in excess of the baseline dropped steadily from 480,000 to 300,000 acre feet--a 38% decline.

Here’s how the ground water basin has declined back toward the level where it was at the end of the last drought and, beyond that, the 1956 “zero” level.

Ground-Water Basin Levels, 1986-90 In acre-feet (the volume of water that will cover an area of 1 acre to a depth of 1 foot) 1986: 480,000 1987: 395,000 1988: 360,000 1989: 315,000 1990: 300,000 Source: Orange County Water District