Ecological rewind - Page 2

Environmentalists want to tear down O'Shaughnessy Dam and restore the Hetch Hetchy Valley, but does their plan hold water?

Kolana Rock towers above Hetch Hetchy Reservoir in Yosemite National Park.

"The loss of Hetch Hetchy Reservoir would fly in the face of every effort San Francisco has made to replace fossil-fuel power generation with renewable energy sources," City Attorney Dennis Herrera wrote in a 2004 editorial in the Guardian. Losing hydropower from the dam, he wrote, "would force greater dependence on fossil-fuel electricity and impair low-cost hydropower with higher-cost renewables, making San Francisco's efforts to create a sustainable energy future virtually impractical. And it would devastate our efforts to enact a public power system in San Francisco. Hetch Hetchy was built by people who envisioned a public power system to serve all of San Francisco. We should finish that system before we start tearing it down."

But when a round of invitations went out to Bay Area journalists to join a three-day backpacking trip in Yosemite and learn about Restore Hetch Hetchy's vision, I signed up to attend. After all, here was a chance to go backpacking in beautiful terrain and assess one of the most controversial and impactful proposals facing San Francisco.



Our first stop within park boundaries was a chocolate-colored chalet with a spacious deck overlooking the waterfront. Owned by the San Francisco Public Utilities Commission (SFPUC), it's notorious in San Francisco politics as a weekend getaway for local elected officials, city commissioners, and favored staffers. Stories of the chalet abound, as it's rumored to have been the site of private soirees for powerful players and a rendezvous for lovers in extramarital affairs.

The eight-mile long, 300-foot deep Hetch Hetchy Reservoir holds 360,000 acre-feet of water, and the dam itself is an impressive structure, although Marshall scoffs at the popular wisdom casting it as "a marvel of engineering," and dryly quips, "so was the Titanic."

Native American remains were buried underwater when it was built, Marshall told us as we peered out over the towering dam wall, and 67 lives were lost during construction. As we rounded the perimeter of the man-made water body, sweating in the summer heat and saddled with gear, he asked us to imagine peering down into a dramatic sloping valley instead of what it looks like in its current state, which is a lake.

"Don't call it a lake," he insisted. Restore Hetch Hetchy regards the reservoir as an unnatural blemish that should never have been imposed upon a scenic and biodiverse environment in a national park. According to Mark Cedorborg, an ecological restoration expert with Hanford ARC and a Restore Hetch Hetchy board member who joined the trip, it wouldn't take long for the natural ecosystem to bounce back if the water were removed, recreating a rare wildlife habitat that would mirror Yosemite Valley.

Sierra Club founding president John Muir would have sided with them, of course. The famous ecologist wrote passionately about the valley and vehemently fought the effort to submerge it. At the time, a chorus of opposition arose against flooding Hetch Hetchy — and that was before modern science documenting the impacts dams have wrought on the environment.

A black-and-white image of Michael O'Shaughnessy, the civil engineer behind the project, is posted on an info kiosk beside the dam, his eyebrows arched in a wizard-like, calculating gaze as he uses a pointer to mark the spot on a map of San Francisco's watershed.

As things stand today, Hetch Hetchy Reservoir is a crucial storage facility for drinking water. Freshwater flowing from the Tuolumne River through the glacial formation accounts for 85 percent of SFPUC deliveries to about 2.5 million customers in the city and on the peninsula.

Hetch Hetchy is unique in that it's just one of a handful of water systems nationwide that uses chemical treatment and ultraviolet disinfection, but no filtration, to purify fresh water that is transported along a gravity-fed system down to the city.