75% Cut in Water Diversion by L.A. Urged to Protect Mono Lake Basin

The city of Los Angeles needs to reduce its diversion of water from the Mono Lake basin by up to 75% in order to preserve the lake’s delicate and unusual ecosystem, the U.S. Forest Service said Tuesday as it unveiled a draft management plan in Los Angeles.

Although the Forest Service cannot legally compel the city to cut back its water consumption, the Mono Basin National Forest Scenic Area management plan was applauded by a spokeswoman for the Mono Lake Committee. The group, which claims 14,000 members, is dedicated to the preservation of the 41,000-acre saline lake east of Yosemite National Park in the Inyo National Forest.

“This is the first time (in recent years) that an independent management agency has looked at the scientific information available, and said, ‘This is what Mono Lake needs to remain alive and healthy,’ ” said Martha Davis, executive director of the Mono Lake Committee.

However, a representative of the Los Angeles Department of Water and Power, which draws about 15% of the city’s water supply from streams that feed Mono Lake, was less enthusiastic about the Forest Service’s recommendations.

Dennis C. Williams, engineer in charge of the department’s aqueduct division, said that if the Forest Service recommendation were to be implemented “there would be a very high cost in terms of replacement water . . . to the city of Los Angeles”

Eventually, Williams predicted, the question of how much water the city draws from the Mono Lake basin will be decided, not by the Forest Service, but in the courts. Half a dozen lawsuits involving the issue are pending, he said.

“I’m confident there’s going to be a balance struck that does protect the environmental resources at the lake, but still provides a reasonable amount of water for the city of Los Angeles,” Williams said.

Dennis Martin, a Forest Service official, said he believes that enough additional sources of water for the city can be found, perhaps among growers in the San Joaquin Valley, to allow the city to reduce its Mono Basin consumption.

“This would be strictly voluntary on the part of the growers to sell water (to the city),” Martin said at a press conference called to announce the Forest Service’s recommendations.

Mono Lake, which features unusual calcium-carbonate formations known as tufa towers, is a home to brine flies and brine shrimp which feed thousands of migrating birds. In addition, islands in the lake provide nesting sites to about 44,000 California gulls.

The lake has been slowly draining since the city of Los Angeles first began drawing off water from the surrounding area in 1941 under licenses granted by the State of California. In the last 47 years, the water level in Mono Lake has dropped about 40 feet and the lake’s salinity has nearly doubled, according to a report prepared for the state Legislature.

Los Angeles currently extracts about 100,000 acre-feet, or 32.5 billion gallons, of water from the Mono Basin each year, Williams said.

At that rate, within 100 years, “the whole ecosystem would collapse,” Martin estimated. To maintain the lake’s current level, Martin said, the city of Los Angeles must reduce its diversions from the basin by 50% to 75%.

In the draft plan, the Forest Service said Mono Lake should be maintained at a level of between 6,390 and 6,377 feet above sea level. The current level is about 6,377 feet.

The water level in Mono Lake is only one of the issues addressed in the Forest Service’s draft management plan, which will be aired at a series of public hearings before it becomes final sometime next year.

Under provisions of the 1984 California Wilderness Act, the Forest Service is responsible for developing a program to manage Mono Lake and an additional 74,000 acres of surrounding land that Congress designated as a federal “scenic area.”

The act directs the secretary of agriculture, who oversees the Forest Service, to protect the Mono Basin’s geologic, ecological, scenic and cultural resources. However, Congress also instructed the secretary to protect existing water rights, including those of the state and city of Los Angeles. That means the Forest Service cannot preserve the water level in Mono Lake if it means cutting back the existing water rights.

The draft plan recommended by the Forest Service analyzed five different management strategies for the Mono Basin, and proposed one that recommends a moderate level of new recreational facilities, encourages research activities, identifies areas where changes in grazing practices are needed, and allows existing, legally valid mining operations to continue.