L.A. Agrees to Shut Owens Valley Pumps : Drought: The DWP gives in on environmental concerns. The decision means a historically low water supply this year and increases the likelihood of rationing.

Under pressure from Owens Valley ranchers and Inyo County officials, the city of Los Angeles has agreed to stop pumping ground water from its Eastern Sierra Nevada properties, foreclosing for one year the opportunity to tap one of the city’s three largest sources of water.

The decision confirms Department of Water and Power projections that it would receive no water from that source this year, leading in part to a historically low supply of water and forcing the city to rely more heavily than ever on an already overburdened Metropolitan Water District.

The MWD is projecting a 12% shortage in water supplies to its member agencies this year that officials hope will be made up by voluntary conservation.

Southern California is facing its shortest water supply in more than a decade as a prolonged statewide drought has begun its fourth year. As a result, Los Angeles Mayor Tom Bradley is asking city residents to cut back water use by 10% or face rationing.

“This is the kind of thing that happens in the fourth year of a drought,” said John Stodder, an aide to Bradley on environmental matters.

The decision comes amid ongoing negotiations with Inyo County officials over Los Angeles’ future water rights in the area and is in response to the prolonged drought and the toll it has taken on the Owens Valley vegetation.

“We need the water, but we cannot accept the future environmental impact of additional pumping” in the Owens Valley, said Rick Caruso, president of the DWP’s Board of Commissioners.

A tentative agreement negotiated last year by the city and Inyo County bars Los Angeles from taking water if it would significantly damage the Owens Valley environment.

Inyo County water chief Greg James last week requested that exports of ground water to Los Angeles be suspended.

“Los Angeles basically agreed with us that ground water pumping should be limited . . . ,” James said. “There really was no debate about it.”

The DWP’s latest reading of the Eastern Sierra snowpack watershed found that runoff into the Owens Valley area this spring will be about half of normal. Also, plant life on the valley floor has dried out from the drought, DWP assistant engineer Duane Buchholz said Tuesday.

In normal years, Los Angeles gets about 60% of its water from the Owens Valley area. Most--about 300,000 acre-feet a year--flows down the Owens River into the Los Angeles aqueduct, but the most controversial issue is the 100,000 acre-feet of water pumped from underground.

Pumping by Los Angeles over the years has been blamed by Inyo residents for lowering the water level in private wells and killing vegetation, particularly the desert valley’s few range trees.

Inyo County and Los Angeles have battled in court over the pumping. After a five-year truce, the two sides agreed last year to a temporary settlement that would place strict limits on environmental damage caused by the Los Angeles pumping wells. Los Angeles could take no more water than nature replaces, and vegetation could no longer be harmed.

But the tentative pact was so heavily attacked by Owens Valley ranchers and longtime residents that Inyo County officials asked for new concessions. Negotiators for Inyo and Los Angeles have been unable to agree on final details.

Under the agreement signed Monday, about 89,000 acre-feet of ground water will still be pumped this year, but it will all be used in Owens Valley for ranches, fish hatcheries and to repair past environmental damage. Last year, the city pumped 154,000 acre-feet from beneath Owens Valley, with about 62,000 acre-feet of it going to Los Angeles.

The agreement does not dramatically affect the DWP’s already bleak projections for this year’s water supply. Officials said they had earlier factored into their calculations the likelihood of having to eliminate that source of water this year.

Dennis Williams, the DWP engineer in charge of the Los Angeles Aqueduct, said the 70,000 to 100,000 acre-feet of ground water normally pumped from the Owens Valley--enough to supply 140,000 to 200,000 households--will be made up through continued pumping of water from the San Fernando Valley and through greater purchases from the MWD.

“It leaves us in very rough shape for next year,” said Caruso of continued pumping in the San Fernando Valley.

The decision will also force the DWP to raise its requests for MWD water by 25,000 acre-feet.

City purchases of MWD water have grown from about 10% of the total consumed in Los Angeles annually just a few years ago, to more than 60% of the projected demand this year. That has put an extra burden on MWD as that water agency is already feeling the effects of the drought.

In response, Mayor Bradley has called on city residents to voluntarily cut water usage by 10%. He said last week it is likely that mandatory rationing will be implemented if the voluntarily effort falls short. Aides to the mayor said that the 10% cut will be measured against usage in 1986--the year the drought began and the first calls for voluntarily conservation went out.