SAN FRANCISCO (KCBS) – San Francisco voters must decide in November whether the city should take a first step towards draining Hetch Hetchy and restoring the natural course of the Tuolumne River.

Proposition F would launch a $8 million study to identify other potential sources of water for San Francisco as part of an overall look at the feasibility of emptying the Hetch Hetchy Reservoir to reveal a valley that famed naturalist John Muir treasured.

KCBS’ Barbara Taylor Reports:

The mayor and Board of Supervisors, and even the progressive Bay Guardian newspaper, have come out in opposition to Water Sustainability and Environmental Restoration Planning Act, which supporters have defended as merely a study whose findings could not be implemented without another popular vote.

“Prop F is all about putting the city on a plan to have a more sustainable future and start to undo the damage it’s done to Yosemite National Park,” said Mike Marshall, executive director of Restore Hetch Hetchy.

The reservoir was created by damming the Tuolumne River in 1923. Gravity carries water from the valley through 167 miles of pipelines, aqueducts and reservoirs to the faucets and taps of 2.5 million people in San Francisco and other Bay Area cities.

“Eighty-five percent of our water supply comes from up in Hetch Hetchy. It only comes here because we have this wonderful system of pipes and tunnels,” said Ed Harrington, the recently retired general manager of the San Francisco Public Utilities Commission.

The Hetch Hetchy Aqueduct has also become a source of hydroelectric power that would also need to be replaced, he said, adding that the SFPUC had spent the last eight years modernizing it.

“It would be a shame to think we didn’t have that system available to us after all the money and time and effort being spent to make sure it’s reliable and safe,” Harrington said.

Marshall suggested there were more efficient ways to store drinking water.

“Let’s consolidate our nine reservoirs and give the Hetch Hetchy Valley back to the American people,” he said.

If the study can find suitable replacements for the Hetch Hetchy’s water and electricity, a second ballot measure would be required in order to implement any action plan for dismantling the current system.

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