The Valley Below A century ago San Francisco dammed a pristine Yosemite valley. Now environmentalists are fighting to tear down that dam, and hundreds of others By Michael Zelenko | Photography by McNair Evans

Over an unseasonably warm weekend this past October, Spreck Rosekrans, the executive director of Restore Hetch Hetchy, led his board members on a hike through a rarely visited corner of Yosemite National Park. The air was hot and breathless, and all around Yosemite, the drought was on full display: where waterfalls still fell, they had thinned from ribbons to threads. Reservoirs in the surrounding foothills had dried up, revealing acres of cracked earth. Because of meager rainfall, the pines that survived 2013’s Rim Fire — the largest ever recorded in the Sierra Mountains — were too desiccated to produce sap, making them vulnerable to a booming bark beetle population. As the tiny insects march through the forest, trees yellow and perish in their wake. The group followed a rocky trail around the northern rim of Hetch Hetchy Reservoir, where 85 percent of San Francisco’s water comes from. In the midst of the worst recorded drought in the state’s history, the reservoir has been a paragon of reliability: a survey last June found Hetch Hetchy to be at 92 percent capacity. Thanks to the reservoir, San Franciscans drink some of the cleanest water in the country — only four other municipalities in the United States have the privilege of foregoing filtration. At the mouth of Hetch Hetchy Valley sits the 430-foot-tall concrete plug that makes all this possible: the O’Shaughnessy Dam. Hetch Hetchy was a replica of Yosemite Valley in miniature But Restore Hetch Hetchy is campaigning to tear down the dam, drain the valley, and revive the landscape that was flooded in 1923. Shaped by the same glacial forces as Yosemite, Hetch Hetchy was a replica of its sister valley in miniature: an idyllic meadow encircled by cascading waterfalls and 1,000-foot-tall, perfectly sheared granite walls. The effort to save Hetch Hetchy is considered one of the first modern environmental campaigns in US history. Restore Hetch Hetchy, a small outfit with two staff employees and roughly 5,000 supporters, is its latest standard bearer. It’s a campaign that puts Rosekrans and his followers in direct conflict with San Francisco politicians and many of its citizens. Senator Dianne Feinstein, once San Francisco’s mayor, has called the reservoir the city’s "birthright" and efforts to remove it "dumb, dumb, dumb." Even as a burgeoning movement is successfully tearing down dams across the country, the century-old Hetch Hetchy campaign remains stuck. Last spring, Restore Hetch Hetchy sued San Francisco in an effort to break the stalemate. The case is winding through California courts, and if Restore Hetch Hetchy ultimately wins, San Francisco will have no choice but to drain the reservoir. A couple miles in, Rosekrans and his group arrived at their final destination: a wooden footbridge that offers a sweeping view from the O’Shaughnessy Dam, across the valley and into the Grand Canyon of the Tuolumne beyond. The bridge sits at the foot of the 1,300-foot-tall Wapama Falls, and during snowmelt, it can be a perilous crossing. But Wapama had also succumbed to the drought. Looking up, all I could see was a stain on the rock where the water should have been. Removing San Francisco’s key reservoir has always been a challenge, never more so than now in the midst of a drought. But Rosekrans is resolute. I asked him why he makes the three-hour drive to see the flooded valley a couple times each year. "I come here primarily to look at how we can do better," he said. "To look at the mistake that we can, and should, fix, and which thousands of people are dedicated to fixing."

For most of our history, Americans have been dam crazy. Dams were some of the first structures colonists built; later, engineering feats like the Glen Canyon Dam were testaments to our ability to harness nature and bend it to our will. Many of these were built to last centuries, if not longer; a monument on Hoover Dam features a star calendar indicating when it was built to whomever, or whatever, discovers it thousands of years from now. Many of these structures continue to serve us: they store our water, mitigate flood risk, and generate electricity — 7 percent of all energy generated in the United States comes from hydroelectric power. But by the 1980s, the era of dam building in the United States had largely come to a close for one simple reason: we’d dammed anything worth damming. The United States has more than 80,000 dams, crossing all of the country's substantial rivers — the Columbia River alone has 14 of them. A small portion of these dams are critical pieces of infrastructure, but many more are vestigial structures that have long outlived their utility, or had little to begin with. According to the Army Corps of Engineers, the primary purpose of nearly one-third of America’s dams is "recreational." we’ve already dammed anything worth damming Environmentalists and engineers have begun re-examining the true cost of dams. Their impact on a landscape can be profound: before the 1930s, California’s Tulare Lake covered 1,200 square miles, making it the largest body of fresh water west of the Mississippi. But farmers in the region plugged and diverted the four rivers that emptied into its basin. Today, nothing of the lake remains. A dam cinches a river’s natural course, breaking an uninterrupted thoroughfare into what Patrick McCully, author of Silenced Rivers, calls "staircases of reservoirs." They halt the flow of nutrient rich sediment from mountains to the valleys below. McCully writes that dams are one of the primary reasons why two-fifths of American fresh-water fish are either endangered or extinct. There are other reasons to reconsider dams: many of them, like our roads and bridges, are aging. The US Army Corps of engineers estimates that a third of the dams it monitors pose a "high" or "significant" hazard. The same week I traveled to Yosemite, severe rain in South Carolina washed out 14 dams and weakened 62 others. Nineteen people died. It was a grim reminder that some of our dams are already coming down, without our help. Over the last two decades, organizations like the Sierra Club and American Rivers have spearheaded a movement to remove nuisance dams. Their campaign has been remarkably successful: between 2006 and 2014, over 500 dams were removed from American rivers — more than were taken down over the entire century prior.

The campaign against O’Shaughnessy Dam is likely the oldest such attempt, and one of the most ambitious. It began toward the end of the 19th century, decades before the dam was even built. Struggling with a booming population, San Francisco sought to plug Hetch Hetchy Valley in order to establish a reliable source of water and electricity. Because of its location high in the mountains, the entire system would be gravity-powered, and the valley’s granite lining would ensure some of the purest drinking water in the country. The plan had one problem: Hetch Hetchy was part of Yosemite National Park. The city was vying to transform one of the country’s most notable landmarks into a water tank. San Francisco was vying to transform part of a national park into a water tank The proposition was met with fierce resistance. One editor at the time declared the country possessed just four "great national features" — Yosemite Valley, Niagara Falls, the Grand Canyon, and the Hetch Hetchy Valley. He added Yellowstone as an afterthought. John Muir called Hetch Hetchy a "great landscape garden, one of Nature’s rarest and most precious mountain temples." In 1892, Muir founded the Sierra Club, and the organization’s first formal action was a lengthy resolution opposing the damming of Hetch Hetchy. Muir and the Sierra Club waged a campaign of persuasion, arguing that the valley held greater value as a refuge than as a reservoir. For the first time in US history, a regional environmental campaign became a national one. Muir ultimately lost — in 1906 an earthquake levelled San Francisco, and the fire that followed consumed 500 city blocks. City officials blamed the extent of the fire on outdated water infrastructure, and in 1913, Congress gave San Francisco authority to flood Hetch Hetchy. Two years later, hundreds of men began logging and scraping the valley bare until nothing remained but a bowl of rock. It took eight years to build O’Shaughnessy dam and another 11 to complete an aqueduct to carry the water 160 miles west. By 1934, Tuolumne River water flowed freely to San Francisco homes. For most Americans, Hetch Hetchy Valley faded into memory.

A few days before the hike around Hetch Hetchy, I visited Spreck Rosekrans in his organization’s two-room Oakland office. It’s a cluttered space, full of schematics, reports, maps, and paperwork overflowing from bookshelves and cabinets. There are pictures, too — lots of pictures. Faded photographs of what Hetch Hetchy once looked like, and colorful illustrations and renderings of what it might look like again. Rosekrans is blond-haired and blue-eyed and speaks with the measured, calculated diction of an engineer. Raised in Berkeley, Rosekrans worked as a white water rafting guide before becoming an analyst with the Environmental Defense Fund in 1988. He met his wife, also a guide, going down the Merced River. "I wanted to see the river. I wanted to see the trees." It was during his time at EDF that Rosekrans turned his attention to Hetch Hetchy. He remembers the first time he saw it: "It was an odd thing to see a version of Yosemite Valley, albeit a little smaller, a little narrower, just as long — quite spectacular. It just seemed wrong to have this concrete plug at the end of it. I just really wanted to see the valley below. I wanted to see the river. I wanted to see the trees." After Muir’s defeat, activists had largely abandoned the cause. But in 1987, Ronald Reagan’s secretary of the interior Donald Hodel brought the idea back to life when he unexpectedly began advocating for restoration and the creation of "a second Yosemite Valley." Sensing a window of opportunity, the Sierra Club launched a Hetch Hetchy Task Force the same year. When the Task Force spun off into Restore Hetch Hetchy, Rosekrans joined its board. In 2009, Restore Hetch Hetchy relocated to San Francisco in an effort to educate the city on the merits of its cause. Three years later, Restore Hetch Hetchy spearheaded Proposition F, a ballot initiative to fund a two-phase evaluation for the valley’s restoration. "This is a values conversation that belongs to the people, not the politicians," Mike Marshall, the organization’s director said at the time.

But the politicians interjected. Mayor Ed Lee, as well as every living former San Francisco mayor, Senator Feinstein, Representative Nancy Pelosi, and the entirety of the city’s Board of Supervisors came out in opposition. "We don’t agree on everything, but we agree that Prop. F would be a disaster for San Francisco," the ballot’s counter-argument read. Mayor Lee called restoration "stupid" and "insane"; the alt-weekly Bay Guardian said it was "a huge waste of time and money." The proposition lost by a landslide, with 76.9 percent voting against. Marshall resigned, and in 2014 the organization retreated back across the bay. "We knew some people would oppose it," Rosekrans told me. "But we underestimated the degree to which the city leaders and politicians would lock arms." Mayor Lee called restoration "stupid" and "insane" When Rosekrans became executive director in 2012, he says his mandate was clear: "I wasn’t the one to run our grassroots campaign. I wasn’t the one to go and lobby Congress for legislation. I was the one to put the lawsuit together." Filed on April 21st, John Muir’s birthday, the suit argues that continued operation of the Hetch Hetchy Reservoir is in violation of Article 10, Section 2 of California’s Constitution, which states that "the public interest requires that there be the greatest number of beneficial uses which the supply [of water] can yield." Restore Hetch Hetchy says the city could retool other reservoirs further down in the system to accommodate the water currently stored at Hetch Hetchy. The valley is a holding tank — not the water’s source. Shifting storage would allow restoration while guaranteeing San Francisco all of its water. Once restored, the valley would be able to serve a greater variety of uses for a wider swath of the population. The lawsuit suggests the value of a restored Hetch Hetchy could be as high as $8.7 billion over the next half-century.

When I spoke with San Francisco Public Utility Commission’s assistant general manager for water, Steve Ritchie, he sounded exasperated. "As long as there is a Restore Hetch Hetchy there will be lawsuits or measures or fundraisers — lots of fundraisers," he said. For the city, the restoration campaign is a perennial irritation. "We’re all struggling to keep what water we’ve got, and it seems like an odd time to file this kind of litigation. But they continue to try to make arguments — and these are certainly creative arguments they’ve put out there," Ritchie added. Estimates for restoration run anywhere from $1 billion to nearly $10 billion. Without Hetch Hetchy as its primary reservoir, San Francisco will be forced to pump and filter its water for the first time in a century, and lose out on the 726 million kilowatt-hours produced by the dam’s system. For San Francisco, the restoration campaign is a perennial irritation "I think about the limited resources that we actually have, and I’d rather spend our money protecting areas that haven’t been disturbed and maintaining this for the functionality that it provides. We don’t have enough money in this world to go around and do every single thing that everyone wants done. We ought to pick our battles," said Ellen Levin, SFPUC’s deputy manager of water. Restore Hetch Hetchy and SFPUC had been in communication since the organization’s founding, but the legal challenge spiked that relationship. "We’re in a lawsuit — that’s a different situation," Ritchie told me. "We don’t see any basis for having a discussion." Rosekrans told me that SFPUC has been less "chatty" lately, but insists Restore Hetch Hetchy has plenty of supporters. "We’ve got some very loyal and committed followers — people really see this as a travesty," he told me. "I don’t anticipate our organization backing out of this any time soon. We’re committed to success here."

To get a better sense for the challenges of dam removal, early one morning I drove from New York City to Pelham, Massachusetts, to see a dam come down for myself. In 2012, a coalition of environmentalists and government officials brought down a 25-foot-tall stone dam over Pelham’s Amethyst Brook. Built in 1820, the dam once powered the largest fishing rod manufacturer in the world but had fallen out of use, and by 2009 it was condemned for safety reasons. Its removal restored a habitat for American eel, brook trout, brown trout, slimy sculpin, and sea lamprey. "Dams on dams on dams" It also exposed yet another dam upstream, this one sticking out just a few feet above the water. Potentially dating back to 1740, this dam was built like a log cabin, with giant timbers piled atop one another and nailed together with wooden pegs. "Dams on dams on dams," said Amy Singler, the associate director of the River Restoration Program at American Rivers, as we followed a trail down toward the brook. It’s not uncommon, Singler said, to find a new dam built directly in front of an older one. With 3,000 dams, Massachusetts is one of the most dammed corners in the country. The temperature hovered in the low 30s, but standing on the bank of a frozen brook, it felt much colder. Around noon an excavator, using its arm like a crutch, lowered itself into the creek bed behind the dam. Log by log, it pulled the structure apart. Each time it plucked out a particularly large piece of wood, the dozen or so engineers, ecologists, and archaeologists gathered on the banks whooped in excitement. Within an hour, it was gone. Fish could now move that much farther upstream; the river would quietly reclaim its path. Laura Wildman, the director of the New England regional office at Princeton Hydro, and one of the nation’s foremost experts on dam removal, told me that so far removal proponents have targeted low-hanging fruit — useless pieces of infrastructure that are well past their prime. The Amethyst Brook dams were typical examples, but there are hundreds of others across the country: in Gainesville, Florida, a community is currently working to pull down a dam that decimated local fish stock and transformed the Ocklawaha River from a robust ecosystem into what one activist called "an ugly abomination." Last month, residents of Fremont, Ohio, upheld a city council ordinance to remove a 102-year-old structure that had, one resident said, "outlived its usefulness." Fall River, Massachusetts, recently received a $35,000 grant to tear down the Bleachery Dam, a structure built to power a bleaching factory that burned down in the 1950s. For more than half a century, the dam remained intact, serving no purpose but still blocking the river. Taking down even a relatively small dam is a slow, expensive, and bureaucratic process. The removal of Amethyst Brook’s stone dam had been in talks for decades, and ultimately cost $350,000. Tearing down the simple timber dam upstream took another two and half years, and an additional $100,000. The larger the dam, the harder it is to remove. In August of 2014, a battery of explosives destroyed the last remnants of the Glines Canyon Dam in Washington, completing the largest dam-removal project in history. Anyone could see why it had to go: the dam had wiped out one of the richest salmon fisheries in the United States and was quickly filling with sediment. Even so, the campaign to remove it took half a century, and its total estimated cost is $325 million.

On November 2nd, Restore Hetch Hetchy won a legal victory: San Francisco had tried to get the case moved from Tuolumne County — where Hetch Hetchy is located — to San Francisco, but failed. In December, the city filed both a demurrer and a motion to strike, in hopes of having the case diminished or dismissed outright. On January 29th, a Tuolumne County judge will hear oral arguments from both sides. Many of the observers I spoke with were dubious of Restore Hetch Hetchy’s chances — taking out a dam when it no longer serves any purpose is a challenge; doing so when it provides millions in the Bay Area with drinking water can seem hopeless. Nevertheless a week before the hearing Rosekrans told me, "We feel good about the merits of our case. We’re excited to move forward." "We feel good about the merits of our case. We're excited to move forward." Over the last decade, other environmental organizations have stepped away from the campaign. The San Francisco chapter of the Sierra Club — the organization Muir built around the valley’s preservation — abstained from taking a position on 2012’s Prop F. Bruce Hamilton, the Sierra Club’s deputy executive director, says he admires Restore Hetch Hetchy’s doggedness and supports its work, but that the Sierra Club isn’t taking a stance on the lawsuit either. "There’s no one advocating that we get involved in ongoing tactics around this campaign," he says. "As a result, [the lawsuit] was never considered. It was never debated. It was never accepted or rejected." A representative from the Environmental Defense Fund, which published the study "Paradise Regained: Solutions for restoring Yosemite’s Hetch Hetchy Valley" in 2004 and was once on the campaign’s frontlines, emailed me to say they support the cause but are no longer actively engaged — other initiatives had taken priority. A few weeks after I came back from Yosemite, I called Robert Righter, a research professor of history at Southern Methodist University. Righter is the author of The Battle Over Hetch Hetchy, the definitive history of the valley. I asked Righter what he thought of Restore Hetch Hetchy’s chances. "I wish I could be more upbeat about that," he said. He doubted that he’d live to see Hetch Hetchy as it once was — or that his children or grandchildren would either. But he took consolation in the long view. Whether by the hand of activists or nature, within a thousand years the valley will come back. In the meantime, "it serves a function for environmentalists," he told me, "those that would want to preserve other mountains, other valleys."