Ecological rewind

Pub date August 9, 2011
WriterRebecca Bowe

Follow the trail from Yosemite National Park’s Rancheria Falls up along dusty switchbacks and down through a canopy of pines and madrones for roughly three miles, and you will reach Tiltill Valley.

Accessible only to hikers and horseback riders, the backwoods meadow hums with the chatter of birds, bees, and the distant rush of water spilling over rocks. Butterflies dart among wild orchids, lilies, yarrow, and other kinds of flowering plants that thrive there, and a lone sequoia stands along the perimeter. The valley floor is lush and boggy, with the forested hills of the High Sierra as its backdrop.

Tiltill Valley is a real-life example of what Yosemite’s Hetch Hetchy Valley might look like if the reservoir that holds San Francisco’s water supply were drained and the terrain allowed to return to its natural state, according to Mike Marshall, executive director of Restore Hetch Hetchy.

His nonprofit group has a singular mission, as the title suggests. The upbeat, 50-year-old former political consultant wants to place a charter amendment on the November 2012 ballot to ask San Francisco voters if Hetch Hetchy Reservoir should be drained so that the valley, which has been underwater since 1923, can be ecologically restored and turned into an attraction for park visitors.

Yet that simply stated goal belies an extraordinarily difficult and expensive task, one that would fundamentally alter San Francisco’s water delivery system and diminish a city-owned source of inexpensive, green energy.

“The destruction of Hetch Hetchy Valley in the 1920s was the worst environmental disaster to ever besiege the national park system,” Marshall says. “And today, it is completely out of whack with the values of the vast majority of people who live here.”

But most city officials think this idea is just plain crazy. Whether or not it was a good idea to build the dam originally, they say it’s unwise and unrealistic to spend scarce resources to destroy one of city’s most valuable assets.

“While it is an interesting idea, I don’t think that there is yet a credible plan to move forward and actually restore Hetch Hetchy that will ensure that within our budget, we’ll be able to get the water that 2.5 million Bay Area customers need, as well as do everything else that the current Hetch Hetchy system does,” Board President David Chiu told the Guardian.

Based in San Francisco, Restore Hetch Hetchy worked in tandem with the Environmental Defense Fund and a consulting firm to craft a technical analysis describing how the city could continue receiving reliable freshwater deliveries without the reservoir, although it would require filtration because of its lower quality and be less abundant in drought years.

While restoring the valley would be an ecological win in a perfect world, cost estimates range in the billions of dollars at a time when budgets are shrinking and economic turbulence rocks the public and private sectors.

Draining Hetch Hetchy Reservoir and replacing it with other water and power projects would punch holes in an already cash-strapped city budget, first with the high capital costs and then with higher long-term annual costs. The hydro-electric system provides carbon-free electricity to city agencies at basement rates and helps fund local renewable-energy projects, so relinquishing some of that generation capacity would be a step backward when it comes to addressing climate change.

“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.

SFPUC spokesperson Tyrone Jue said Hetch Hetchy water does not require filtration “because basically, it’s a giant granite basin there in the reservoir, so there’s no sedimentation.” He added that the water quality is exceptionally high. “It’s high up in the watershed. The higher up in the watershed, the better it is.”

Restore Hetch Hetchy has submitted a number of proposals to ensure that San Francisco could still receive adequate supplies without the reservoir, including constructing a new intertie at Don Pedro Reservoir, which lies downstream from Hetch Hetchy, to get drinking water supplies from there instead.

Under this scenario, the SFPUC would continue to get its water from the Tuolumne River — but it would have to build a new filtration system to treat it because the water quality would be worse and the city would lose its federal waiver.

That’s an expensive consideration, particularly at a time when city coffers are depleted, critical services for vulnerable populations have been gutted, and taxpayers are wary of authorizing costly new endeavors.

Marshall defends the cost by asserting that the current system is flawed; the lack of filtration makes San Francisco’s water more susceptible to contamination from nasty microorganisms like cryptosporidium and giardia, he says.

“San Francisco has a unique health demographic in that over 5 percent of the people that live in the city have compromised immune systems, if you just look at people who are HIV positive,” he said. “Ultimately, San Francisco is going to be forced to filter its water, so why are we kicking this can down the road?”

But filtering water at the residential level would be far cheaper than tearing down the dam. Jue pegs the cost of a new filtration system at somewhere between $3 billion and $10 billion, but Marshall rejects that estimate as “just crazy.”

So we called Xavier Irias, director of engineering at the East Bay Municipal Utility District. “Ten looks a little high, but the three sounds very credible,” Irias said, acknowledging that there were many complicating factors that could affect cost. Ultimately, he said, the cost range could be anywhere from half a billion to the single-digit billions of dollars.

“With the filtration costs, not only are you talking about building a facility to filter the water, you’re now talking about increased power consumption to basically power those filtration plants,” Jue noted. “You’d have to start pumping water, which would require additional energy. And then on top of that, there’s the long-term operation.”

What’s more is that the quantity of water that San Francisco now depends on wouldn’t be guaranteed every year. According to an analysis done in partnership with the Environmental Defense Fund, reconfiguring the system to tap Don Pedro would result in 19 percent less water delivered from the Tuolumne in critically dry years, and similar losses would result from alternative proposals like tapping Cherry Reservoir, another storage facility in the SFPUC system.

Restore Hetch Hetchy has suggested that the shortfall could be made up in part with new water-conservation measures, something that cities arguably ought to be practicing anyhow since climate change threatens to bring about drier conditions in California’s watershed. It could also place the city in the position of having to go to the open market to purchase water for customers — just as dwindling water supplies raise the temperature between cities and counties scrambling to secure reliable deliveries.

“The Hetch Hetchy water system is a fully owned public asset,” Jue notes. “At a time when state and federal governments are struggling with even being able to close our budget deficits, to even look at dismantling an environmentally sound, cost-efficient water system that delivers water to 2.5 million people is sort of outrageous.”



In addition to capturing the flow of pristine Tuolumne River water that eventually makes its way into the city’s plumbing network, O’Shaughnessy Dam is a key component of the SFPUC-owned hydro-electric system, which produced 1.7 billion kilowatt hours of power last year with no greenhouse gas emissions.

If efforts to advance the cause of a public power system resurfaced in San Francisco, having the full capacity of the Hetch Hetchy hydro-electric generation in place would be vital. Juice for city streetlights, Muni’s light rail cars, the chandeliers adorning the Board Chambers in City Hall, and countless other municipal uses are derived from this gravity-fed system, which provides roughly one-fifth of San Francisco’s overall energy needs.

City departments pay three or four cents per kilowatt-hour, less than what it costs to generate the power. If all the hydro-electric power were eliminated and substituted with PG&E power, the city would get pinned with $32 million in additional costs annually, and its carbon footprint would expand by more than 900 million pounds of greenhouse-gas emissions, according to the SFPUC. However, a technical report produced by the Environmental Defense Fund suggests the city would only suffer a 20 percent decline in the hydro-electric output, since operations at other SFPUC reservoirs would continue.

The hydro-electric system also generates revenue through the sale of excess power to Turlock and Modesto irrigation districts, but that would come to an end if the generation capacity fell by 20 percent. Restore Hetch Hetchy estimates this loss to be around $10 million annually.

“Whenever we sell the power to Modesto and Turlock, that revenue then goes to fund programs like GoSolarSF, and all of our energy-efficiency retrofits of municipal facilities,” Jue explains. If the city lost its ability to sell off this excess supply, “We would no longer be getting power revenue at all, which we’re using to help fund community choice aggregation.”

Fraught with problems as it is, the city’s effort to launch a community choice aggregation program offering residential customers an alternative to PG&E nevertheless holds promise as a powerful green shift for a major metropolitan hub. For all the ecological benefits to Yosemite, restoring Hetch Hetchy could wind up undercutting the fledgling green power initiative, and the upshot would be a boon for PG&E. Coupled with the fact that ceding control of the valley back to the National Park Service could strip the city of its mandate for public power, the utility giant would benefit tremendously from this plan.

All of this makes it somewhat surprising that District 5 Sup. Ross Mirkarimi, a longtime champion of the cause of public power, appointed Marshall to serve on the SFPUC Citizens Advisory Committee, a move that rankled SFPUC staff.

“I’ve known Mike many years and have found him to be whip smart when it comes to complicated policy issues,” Mirkarimi told the Guardian when asked about this. “He knows that I am an unwavering supporter for public power and that I’d hope his advocacy on the SFPUC continues to advance and innovate our locally-driven clean energy objectives.”



The concept of bringing back Hetch Hetchy Valley originated with the Sierra Club in 1999, and several mainstream environmental organizations have lent support for the cause although few have made it a high priority. Nevertheless, there’s plenty of financial backing and support from key political players to keep the vision alive.

Democratic County Central Committee Chair Aaron Peskin, a member of Restore Hetch Hetchy’s national advisory board, told me he’s been active with the group for at least a decade, making him a rare exception among the city’s political leaders.

“San Francisco is a remarkably sophisticated town that is technologically advanced and environmentally advanced, and this is an opportunity to right one of the most destructive environmental wrongs,” he said. “It’s time to start a local and national conversation.”

He acknowledged that there were a lot of technical issues to contend with, saying, “It should only be done in a way that makes sure San Francisco and communities that rely on the system are taken care of.”

Major funders backing Restore Hetch Hetchy include retired businesspeople from the financial sector, Patagonia founder Yvon Chouinard, council members of the Yosemite Conservancy, and Lance Olson, a Restore Hetch Hetchy board member and partner in Olson Hagel & Fishburn, LLP, a prominent Sacramento legal firm that represents the California Democratic Party and elected officials.

Other influential and politically connected individuals have joined the effort as well. Marshall assured me that “no one from PG&E has given us a dime.” Yet the project still faces some powerful opponents. “I have opposed removing the O’Shaughnessy Dam in Hetch Hetchy Valley for decades and I remain opposed,” U.S. Sen. Dianne Feinstein told the Guardian. “Draining the reservoir would endanger San Francisco’s water supply, further jeopardize California’s water infrastructure and impose a huge financial burden on the state.”