Groundwater use in Utah was up an estimated 91,000 acre-feet last year - or 13 percent - according to the latest survey by the U.S. Geological Survey and state Natural Resources Department.

The estimated withdrawal of 779,000 acre-feet from groundwater wells in 1987 was up from 1986 and about 21,000 acre-feet in excess of the estimated annual average from 1977-86, according to USGS spokeswoman Gail Cordy."The increase in withdrawal was predominantly for irrigation and public supply," Cordy said.

Groundwater use is related to climate, demand and availability of water from other sources.