Redwood Valley water officials are girding for emergency action as a shrinking Lake Mendocino threatens to drop below the pumping intake.

"At the rate we're dropping, we have approximately 60 days before our intake pops out" of the water, said Redwood Valley County Water District manager Bill Koehler. The district is the only water agency that takes its water directly from the lake.

The district serves about 4,000 residential customers and 200 agricultural users north of Ukiah.

Other agencies that utilize Lake Mendocino water primarily draw it from wells fed by underflow from the Russian River below Lake Mendocino.

All will be scrambling for water if drought conditions persist.

Without rainfall, the lake could disappear in 230 to 670 days, depending on water flows into and out of the lake, evaporation rates and amount of lake sedimentation, according to the U.S. Army Corps of Engineers.

The surface level on Tuesday fell to 706.9 feet above sea level and the reservoir held 25,503 acre feet of water.

The lake bottom is at about 641 feet above sea level. The Redwood Valley water district's water intake pipe is at roughly 695 feet above sea level, about 11 feet below the current surface, Koehler said

The Redwood Valley water district on Thursday will be discussing ways to deal with the problem should rain continue to bypass the North Coast. Its board also is expected to discuss possible water restrictions . They've already been asked to voluntarily reduce water consumption, Koehler said.

Koehler said the district has several emergency contingency plans, including one that should allow the district to pump from the lake for an additional 60 days. The district, established in the late 1970s, has never before implemented the plan, Koehler said.

It includes placing a temporary pipe deeper in the lake and pumping the water into the concrete intake structure that holds about 190,000 gallons, Koehler said.

Other water agencies in Mendocino and Lake counties also are considering measures this week to deal with the continuing rainfall shortage.

Most of the small agencies in the Ukiah Valley currently have sufficient water for indoor use but are considering asking their customers for voluntary reductions.

Several Ukiah Valley water districts are working on a joint water conservation plan, said Dave Redding, manager of the Willow County Water District just south of Ukiah. He's suggesting that households limit usage to about 250 gallons a day, the average winter water consumption for the district.

City of Ukiah officials say they have sufficient water for winter use, which assumes people aren't watering their landscaping. They are asking for voluntary curtailment of outdoor water uses.

The city of Willits has adopted the most serious water restrictions so far. City officials last week imposed mandatory restrictions that limit households to 150 gallons per day. Willits' water reservoirs contain an estimated three month water supply.

You can reach Staff Writer Glenda Anderson at 462-6473 or glenda.anderson@pressdemocrat.com.