Time: “To some, the O’Shaughnessy Dam is a monument to the skills of the Irish-American engineer who built it. Elegant is the word that Susan Leal, general manager of the San Francisco Public Utilities Commission, uses to describe the curved wedge of rock and concrete that soars 300 ft. above the floor of the Hetch Hetchy Valley. But to others, the dam, constructed nearly a century ago inside the western boundary of Yosemite National Park, is a mocking tombstone to a landscape whose haunting beauty has lain for too long beneath 100 billion gallons of water.
Might the O’Shaughnessy Dam one day be dismantled and that drowned landscape conjured back into being? That is the provocative question posed by an activist group called Restore Hetch Hetchy, which five years ago launched a spirited but seemingly quixotic campaign to convince the public that the time has come to get rid of the unnatural bone lodged in the valley’s throat. “This was done by people, and it can be undone by people,” says Restore Hetch Hetchy’s executive director Ron Good.
Undoing dams that have outlived their usefulness–or whose social and economic utility is overshadowed by the environmental harm they do–is an idea that is catching on. Over the past six years, some 175 dams have been dismantled across the country, and more than 600 over the past century. That’s just a drop in the millpond, however, given that there are perhaps 2.5 million dams in the U.S. and that most of those removed to date have been relatively small and insignificant.”