By growing less thirsty crops and investing in more efficient irrigation technology, California farmers could save billions of gallons of water each y

In a study to be released today, researchers at Oakland's Pacific Institute say that before Californians take on costly new dam and reservoir projects, state and federal policymakers need to build on existing methods for reducing agricultural water use.

The report, titled "More with Less: Agricultural Water Conservation and Efficiency in California - A Focus on the Delta," stresses that agriculture remains an important part of California's economy. However, with farmers using about 80 percent of the water drawn from the critically ill Sacramento-San Joaquin Delta, researchers said agricultural water conservation must expand - and quickly.

"No one has ever evaluated the potential for improving the efficiency of agricultural water use," said Peter Gleick, president of the Pacific Institute and co-author of the report. "We found there is a lot of potential for savings ... and they're extensions of things farmers are already doing."

Farmers who shift away from water-intensive crops, invest in high-tech watering systems and irrigate only at precise times in the growing cycle could save between 600,000 and 3.4 million acre-feet of water each year, Gleick said. One acre-foot is roughly 326,000 gallons, and represents the amount of water needed to cover 1 acre of land to a depth of 1 foot.

The study is part of a larger report to be released by the nonpartisan research group next year and was funded by the David and Lucile Packard Foundation and the William and Flora Hewlett Foundation.

While water use in California has been a historical source of conflict between urban and agricultural consumers, the issue has taken on new urgency in recent years amid predictions of a drier climate, booming population growth and ecological damage to the delta - the hub of the state's water system.

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