It would cost $3 billion to $10 billion to drain Yosemite’s Hetch Hetchy Valley — currently submerged under 300 feet of water — and replace the reservoir’s water and power, a state agency reported Wednesday.
Although the Hetch Hetchy Valley is within a national park, San Francisco possesses a personal stake in the reservoir’s future. San Francisco owns the dam, and 2.4 million residents in San Francisco, Alameda, San Mateo and Santa Clara counties consume Hetch Hetchy water. The reservoir’s releases also generates hydropower used by The City.
Both proponents and critics of the ambitious idea to restore the valley to its original state have long awaited the Department of Water Resources report, which was commissioned by Gov. Arnold Schwarzenegger in 2004. Within its 68 pages, both sides found support for their cause.
Environmentalists, following in the footsteps of Sierra Club founder John Muir, who battled the plan to dam Hetch Hetchy 100 years ago, argued with the state’s cost estimate but said the report validated the feasibility of the restoration plan.
"The current body of information puts a lot of emphasis on costs and not enough on benefits," Restore Hetch Hetchy Executive Director Ron Good said in a statement.
The restored valley would draw tourism with its accompanying economic benefits, as well as provide a boost for the environment, Good said.
San Francisco Board of Supervisors President Aaron Peskin, however, called the restoration idea "an expensive proposition with many unanswered questions."
"Obviously that was one of the great environmental tragedies of almost a century ago," he said of the decision to dam the valley. "Reversing that now seems like it’s a visionary concept, but it also seems like a daunting uphill battle."
On Wednesday, the San Francisco Public Utilities Commission, which oversees the operation of Hetch Hetchy, sent out a press release noting the "monumental challenges of draining Hetch Hetchy" and included quotes from U.S. Senator Dianne Feinstein and Assemblyman Mark Leno in support of keeping the Hetch Hetchy reservoir dam in place.
"It doesn’t make sense," said Susan Leal, general manager of the San Francisco Public Utilities Commission. "I hope the report will put this idea to rest, with the enormous costs of undoing a source of pristine water and clean power. We have bigger priorities in San Francisco and the Bay Area, and I’m assuming the state has bigger priorities as well."
Recent studies by UC Davis and the Environmental Defense Fund have noted that diverting the water to other reservoirs couldprovide a desirable water source alternative, although critics, including Mayor Gavin Newsom, have worried that The City’s water rights would be lost in the process.
The state has no plans to take further steps for or against the Hetch Hetchy restoration plan, said Sue Sims, spokeswoman for the state’s Department of Water Resources. Because Hetchy Hetchy Valley is located in a national park, the federal government would likely have to get involved in any continued effort to remove the dam, she added.