State high court rejects Berkeley group’s suit to drain Hetch Hetchy Reservoir

FILE-- Visitors explore the shoreline of Hetch Hetchy reservoir in Yosemite National Park, California, on Thurs. July 28, 2016. The California Supreme Court rejected a conservation group’s lawsuit Wednesday seeking to drain Yosemite’s Hetch Hetchy Reservoir, a source of water for San Francisco and surrounding Bay Area communities. less FILE-- Visitors explore the shoreline of Hetch Hetchy reservoir in Yosemite National Park, California, on Thurs. July 28, 2016. The California Supreme Court rejected a conservation group’s lawsuit Wednesday ... more Photo: Michael Macor / The Chronicle 2016 Buy photo Photo: Michael Macor / The Chronicle 2016 Image 1 of / 7 Caption Close State high court rejects Berkeley group’s suit to drain Hetch Hetchy Reservoir 1 / 7 Back to Gallery

The California Supreme Court rejected a conservation group’s lawsuit Wednesday seeking to drain Yosemite’s Hetch Hetchy Reservoir, a source of water for San Francisco and surrounding Bay Area communities.

Restore Hetch Hetchy, a Berkeley group, argued in its suit that the location of the dam and reservoir, which flooded a valley in the park after construction in 1923, violates a provision of the California Constitution requiring reasonable water use.

But a state appeals court in Fresno ruled in July that Congress had overridden state laws when it authorized construction of the dam and reservoir. The state’s high court denied a hearing Wednesday on the appeal by Restore Hetch Hetchy, without any dissenting votes.

The conservation group said it would seek review in the U.S. Supreme Court.

The reservoir on the Tuolumne River has been controversial since it was first planned. Naturalist John Muir campaigned against building a dam in the scenic Hetch Hetchy Valley and said the granite domes and towering waterfalls should not be sacrificed for a municipal water supply.

But San Francisco was desperate for water, especially after the shortage of its reserve supply was shown in the 1906 earthquake and fires.

President Woodrow Wilson signed the Raker Act in 1913, authorizing construction of the O’Shaughnessy Dam, which created the Hetch Hetchy Reservoir and flooded the valley.

The reservoir now anchors a waterworks that serves 2.7 million residents and businesses in more than a dozen Bay Area communities. It also generates hydroelectric power.

Restore Hetch Hetchy first challenged the operation at the ballot box, qualifying an initiative in 2012 that would have required San Francisco to explore removing the dam. But voters turned it down.

The group then filed suit in 2016. A year later, Tuolumne County Superior Court Judge Kevin Seibert rejected arguments that the project violated state law and said the federal government had legally authorized construction. The appeals court agreed in July.

“Congress specifically ordered the creation and operation of a dam, intending for the continued operation of this structure,” Presiding Justice Brad Hill said in the 3-0 ruling. “These commands required the construction of a dam that would flood the Hetch Hetchy Valley.”

San Francisco City Attorney Dennis Herrera said Wednesday the lawsuit “was misguided from the start.”

“The last thing California needs to do right now is jeopardize clean drinking water for millions of residents,” he said.

Restore Hetch Hetchy’s executive director, Spreck Rosekrans, said the group hopes for better results in the U.S. Supreme Court and will seek help from lawmakers in Sacramento and Washington, D.C. He said the city has other water sources available, including another reservoir and water recycling.

“San Francisco’s occupation of Hetch Hetchy is the greatest travesty that has ever taken place in any of our national parks,” Rosekrans said. “Hetch Hetchy Valley can and will be restored to its natural splendor without losing a drop of San Francisco’s water supply.”

The case is Restore Hetch Hetchy vs. San Francisco, S250654.

Bob Egelko is a San Francisco Chronicle staff writer. Email: begelko@sfchronicle.com Twitter: @BobEgelko