Removal of Yosemite Dam to Be Studied

SAN FRANCISCO —  Gov. Arnold Schwarzenegger’s resources secretary has directed his agency to study possible restoration of the Hetch Hetchy Valley in Yosemite National Park, giving an unexpected official boost to the controversial idea of dismantling the dam that has been integral to the Bay Area’s water supply for more than 80 years.

Mike Chrisman’s decision came at the request of Assembly members Lois Wolk (D-Davis) and Joe Canciamilla (D-Pittsburg), and less than two months after the nonprofit group Environmental Defense released a study detailing possible alternatives to the Bay Area’s sources of drinking water and hydroelectric power.

In a written response this week to the two legislators, Chrisman said he has asked the Department of Water Resources to review 20 years’ worth of restoration proposals.

He added, “California, its governor and its citizens are committed to economically feasible restoration of ecosystems and preservation of open space. This commitment translates into an interest in reasonable proposals for expanding our trust resources.”

The Hetch Hetchy system supplies water to 2.4 million Bay Area customers. Key to that system is the O’Shaughnessy Dam, which submerged the Hetch Hetchy Valley, which many consider Yosemite Valley’s once equally beautiful twin, under 300 feet of water in 1923.

Previous proposals to tear down the dam and restore the valley have gone nowhere, and the latest one, by Environmental Defense, was criticized as irresponsible by U.S. Sen. Dianne Feinstein (D-Calif.), a former mayor of San Francisco, whose support in changing federal law would be critical.

“In a state that has faced repeated droughts and is desperate for water sources, I believe this would be a terrible mistake,” she said.

Agencies that own and operate the water system and represent Bay Area consumers also expressed skepticism, stressing that a safe and reliable water source is the region’s top priority. The director of the Bay Area Water Supply and Conservation Assn., which represents numerous water agencies in the region, said the group would not support the idea until alternate facilities were operating.

Any solution also would have to involve the Turlock and Modesto Irrigation Districts, which own the Don Pedro Reservoir downstream on the Tuolumne River.

Still, Tom Graff, Environmental Defense’s California regional director, said support from the Schwarzenegger administration for further study is a start.

“This is but one step on a long road, but I think it’s a significant step,” he said. “The state administration has basically said this is worthy of study. We applaud them for agreeing to that and for trying to now herd the other stakeholders and people involved.”

In his letter to the two legislators, Chrisman said he also asked the Department of Water Resources to work with the National Park Service to place an economic value on a restored Hetchy Hetchy Valley, which could relieve pressures of heavy visitation on Yosemite Valley.

But the letter struck a cautious note, stressing the state’s need for a net increase in water storage. “Any plan to remove or modify existing water storage systems would need to be balanced by a viable plan to, at a minimum, replace the water supply now provided by the Hetch Hetchy Reservoir,” Chrisman wrote. And he warned that the state’s study would be of “limited value” unless affected local agencies and federal officials participated.

The San Francisco Public Utilities Commission, which runs the Hetch Hetchy system, is beginning a $3.6-billion overhaul. Restoration backers want environmental studies that must precede the overhaul to examine the possibility of razing the dam.

In its study, Environmental Defense concluded that San Francisco could continue to receive most of its drinking water and hydropower from the Tuolumne River by using the Eleanor, Cherry and Don Pedro reservoirs, also located on the Tuolumne. A pipe connecting Don Pedro to the city’s water delivery system would be required.

A recent engineering study by researchers at UC Davis also concluded that Hetch Hetchy was no longer critical to the state’s water storage, and that downstream reservoirs, including Don Pedro, could store the same amount of water.

Wolk and Canciamilla, chairman of the Assembly Water, Parks and Wildlife Committee, asked Schwarzenegger in September to pursue a state-sponsored study.

“We urged him ... that this was a once-in-a-lifetime opportunity and could be a true legacy,” Wolk said, and “that the magnitude of it really required that the state and the governor take the leadership role and do a study to see if this really did make sense.”

Wolk said plans for a state-sponsored study, also supported by Assemblyman Tim Leslie (R-Tahoe City), were encouraging.

“No one should be afraid of a full, complete and balanced study,” she said. “I encourage everyone to come to the table in good faith to assist the state in preparing a thorough analysis of all the options.”