Deep under the shimmering waters of the Hetch Hetchy reservoir in California there's a valley that rivals the beauty of Yosemite, a jewel in the crown of the national park system.
Some are calling, again, for the reservoir flooded nearly 100 years ago to be drained and the valley that naturalist John Muir called a "mountain temple" to emerge.
There's one major problem, critics say: The reservoir is a major source of water for 2.4 million Bay Area citizens even as the state struggles with one of the worst droughts in modern history.
A California activist group’s petition challenging the legality of Hetch Hetchy has set off the latest battle in a century-old fight over the reservoir and the Yosemite valley that it fills.
“Draining the reservoir, an essential part of the [Hetch Hetchy] System, could be a serious threat to the users who depend on it and to the California economy,” Nicole Sandkulla, CEO of the Bay Area Water Supply and Conservation Agency, said in a statement. BAWSCA was named as a co-defendant in the recent court filing by Restore Hetch Hetchy.
Often considered a sibling to the larger Yosemite Valley, the Hetch Hetchy Valley lies entirely within the bounds of Yosemite National Park, and its grassy floor and granite walls were widely admired before the federal government gave the go-ahead in 1913 to build the O’Shaughnessy Dam. The fight around the original dam proposal was one of the first major environmental causes in American history.
The petition filed by Restore Hetch Hetchy in Tuolumne County Superior Court on April 21 seeks to challenge the existence of the dam and the reservoir by saying they violate California’s state constitution, which requires that the supply of water be divvied up for “the greatest number of beneficial uses which the supply can yield.”
“Operating a dam and reservoir in an iconic valley within Yosemite National Park is not, in 2015, a reasonable method of diverting water for municipal uses,” the petition states. It also asks for San Francisco to come up with engineering and financial plans that would make it possible to drain the reservoir and restore the valley.
The San Francisco Public Utilities Commission thinks the new suit is “baseless,” spokesman Tyrone Jue said. He emphasized that the entire Hetch Hetchy system supplies water to about 7 percent of the state’s population, and that reports have outlined costs of between $3 billion and $10 billion to take down the dam and restore the valley.
“The idea that you would be encouraging a study looking at draining the water supply for that number of people during California’s worst drought doesn’t make a lot of sense,” Jue said.
The idea of draining Hetch Hetchy will likely strike many others the same way, as the state endures the fourth year of a drought that shows no sign of slowing down. The reservoir was at 75 percent capacity as of May 5, totaling 269,963 acre-feet of water (an acre-foot is nearly 326,000 gallons). For that same date, California’s Department of Water Resources said the snowpack –- an important measure that helps determine how much water the state may have down the road -– was at 1 percent of normal.
“There are real challenges in California when it comes to keeping our rivers healthy, keeping the Bay Delta healthy, and determining how much water gets diverted to rivers and farms,” said Restore Hetch Hetchy executive director Spreck Rosekrans. “Hetch Hetchy is not that sort of issue. Not one drop of water needs to be lost, it can all be captured downstream. It’s not really about water use, it’s about land use.”
Rosekrans said that with some additional upgrades the rest of the Hetch Hetchy System, which includes 8 other reservoirs, could handle the water currently stored behind O’Shaughnessy Dam. In 2006, graduate student Sarah Null and Jay Lund, a professor at the University of California, Davis, published a report that found the dam could be removed without much effect on the water supply -– though San Francisco would have to hash out deals with the water agencies that manage those other reservoirs.
“You could take out this dam with really negligible water scarcity to urban and agricultural users,” said Null, now assistant professor of water resource management at Utah State University.
There would be other costs that would come with removing the dam, however, including the loss of approximately $12 million in hydropower a year, according to their study. It could also result in a spike in Bay Area water bills, in part due to the loss of a rare filtration waiver that comes with Hetch Hetchy’s unusually pure waters. Null said that their work shows that it would be possible to take down the dam without losing significant amounts of water -– and that more dams don’t always guarantee a greater water supply.
“At some point, and California is learning this in particular now, the challenges have to do with simply not having enough water,” Null said. “So having lots of dams, you basically have a lot of cups that might stay empty. More cups don’t necessarily mean more water.”
Over the years, the idea of removing the dam has been entertained by people from across the political spectrum, from the Sierra Club to Republican White Houses. In the 1980s, President Ronald Reagan’s Interior Secretary, Donald Hodel, was in favor of draining the reservoir and restoring Hetch Hetchy to its natural state, telling the Los Angeles Times in 1987 that it could open up “a second Yosemite Valley.” President George W. Bush put a line in his fiscal year 2008 budget proposal that would have given the National Park Service $7 million to look at draining Hetch Hetchy, but that idea was scuttled by the House of Representatives.
But in San Francisco, proposals to pull down the dam have been consistently sunk. Nearly 77 percent of voters in San Francisco County voted against a 2012 ballot proposition that would have allocated $8 million toward Hetch Hetchy restoration plans. Senior California Senator Dianne Feinstein has opposed the idea of draining Hetch Hetchy since she was mayor of San Francisco in the 1980s. The senator’s office declined to comment for this article.
If these objections are ever overcome and a decision is made to remove the dam, what would that process even look like?
Objective information around reclamation for the Hetch Hetchy Valley is scattered, but some does exist. A 1988 analysis by the Bureau of Reclamation investigated possible replacements for the water and power-generating capacity of the O’Shaugnessy Dam, and found options that “appeared promising for further study.” Another report, this one published in 2004 by researchers at the University of Wisconsin, looked at whether the reservoir could be drained in stages over many years, giving plants and other wildlife time to take root against invasive species.
And the idea of removing a dam has become increasingly accepted in recent decades. More than 1,000 dams have come down across the United States in the past four decades, and in a recent review published in the journal Science researchers from the U.S. Geological Survey and U.S. Forest Service found that most rivers recover within a matter of years.
For now, Rosekrans said he thinks RHH has a “strong case,” and that he is waiting for San Francisco to respond to the suit.
“It’s our hope that we get a declaratory ruling and that San Francisco decides they don’t want to be out of compliance with California law and they develop and implement a plan that will restore the valley and return it to the American people,” Rosekrans said.