In a ballot on November 6, San Franciscans voted by 77% to 23% against Proposition F, which would have required the city to study draining Hetch Hetchy Reservoir in Yosemite National Park. Details can be found here.
The reservoir was created in 1923 to provide water for the San Francisco area. It was created by the damming of the river that runs through the Hetch Hetchy valley, which was formed by glacial action about 10,000 years ago and is a twin of Yosemite valley. The dam was built despite opposition from the Sierra Club, led by John Muir. Hydrologists say that draining the reservoir should not affect water supplies significantly, as the nearby Don Pedro reservoir holds more than twice as much water as Hetch Hetchy.
"This is the beginning, not the end," said Mike Marshall, executive director of Restore Hetch Hetchy, the group that sponsored the measure. "We went into this wanting to educate folks about the water system and how it impacts Yosemite. We lost, but our movement is going forward".
More information about the background to this story can be found here.