UPDATE: Voters Block Study To Drain Yosemite's Hetch Hetchy

A controversial vote by San Francisco residents on Sunday put another nail in the coffin for Yosemite National Park's Hetch Hetchy Valley, or what John Muir called "one of nature's rarest and most precious mountain temples." 

In 1913, the valley was buried under 300 feet of water when the City of San Francisco built the O'Shaughnessy Dam across the Tuolomne River. The project was hotly debated and John Muir, the famous American conservationist, and other Sierra Club leaders tried passionately to stop it.

"Dam Hetch Hetchy!" Muir wrote in his book The Yosemite. "As well dam for water-tanks the people's cathedrals and churches, for no holier temple has ever been consecrated by the heart of man."

Proposition F would have budgeted $8 million to create a plan to drain Hetch Hetchy, and an additional vote would have allowed San Franciscans to decide whether or not to go through with the plan. On Sunday, however, the proposition was shut down by 77 percent of voters.

Many of the plan's critics were very vocal, including San Francisco Mayor Ed Lee who called the idea "insane." Water, Lee said, was a precious commodity in California and no city should risk losing a reliable water supply.

The vote was disappointing for environmental groups such as Restore Hetch Hetchy and the California League of Conservation Voters, who said the measure was an opportunity to undo one of the great environmental wrongs of the 20th century. They also pointed out that draining the reservoir would not significantly harm the Bay Area's water supply. The loss of the 360,000-acre feet of water-storage space could be offset through more water conservation, water recycling and other water storage areas.

Hydrologist Jeffrey Mount from the University of California at Davis, said another reservoir near Hetch Hetchy called Don Pedro holds more than twice as much water. And, although it would be expensive, moving the pipes to this reservoir would not be complicated.

Even if climate change worsened water scarcity, undamming Hetch Hetchy wouldn't make things much worse for the golden state, said Sarah Null of Utah State University in Logan. She modeled California's future water supply and said that even in the worst case climate scenario, the loss of Hetch Hetchy would cause the Bay Area only minor additional shortages.

A complete restoration project would have cost between $3 billion and $10 billion, according to a 2006 study by the Department of Water Resources. After draining, Hetch Hetchy would be a muddy mess, but with decades of careful management, the ecosystem could be restored. Although the valley's reapperance would have little or no effect on downstream species, the meadows, coniferous and deciduous forests and wildlife that once flourished there, and that Muir so loved, could return.

To see a comparison of Hetch Hetchy before and after the dam, check out this interactive feature from Sierra Nevada Photos.

Via New Scientist and MercuryNews.