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Protect Our Parks

See the Most Controversial Spot in Yosemite near the Hetch Hetchy Entrance

One hundred years after flooding Hetch Hetchy, central California’s water struggles have only intensified.

Today, when the 1% of Yosemite visitors who make it through the Hetch Hetchy Entrance look out at the landscape, they see a vast expanse of blue water, ringed by granite mountains with waterfalls tumbling down their faces. A hundred years ago, however, the view looked a little different.

When naturalist and conservationist John Muir first visited the valley, he wrote that it was “a grand landscape garden, one of Nature’s rarest and most precious mountain temples.”

In Muir’s day, Hetch Hetchy was a wide, grassy valley with the Tuolumne River winding its way along the floor. Trees dotted the river bank and wildlife was abundant. It had been the summer home of the Miwok and Paiute people for more than 6,000 years and the tribes had periodically burned the floor to maintain the lush meadows. It looked a little something like Yosemite Valley. Some argue, even more beautiful.

1908: View across Hetch Hetchy Valley, from the southwestern end, showing the Tuolumne River flowing through the lower portion of the valley prior to damming.
1908: View across Hetch Hetchy Valley, from the southwestern end, showing the Tuolumne River flowing through the lower portion of the valley prior to damming. (Photo: Wikimedia Commons/Isaiah West Taber Public Domain)
2016: View of Hetch Hetchy Reservoir after damming.
2016: View of Hetch Hetchy Reservoir after damming. (Photo: Getty Images)

Muir was one of the strongest voices in the lobby to make Yosemite a national park, a designation made by Congress in 1890. At this point in history, national parks were a newly minted concept and weren’t yet regulated by the National Park Service Act. In those days, bears were being fed to delight visitors in Yellowstone, antiquities were being taken from Mesa Verde and San Francisco had its eye on the Tuolumne River.

Damming Hetch Hetchy

Following the devastating 1906 earthquake and the subsequent fires where 80% of the city was destroyed, San Francisco’s need for a more-robust water source became crystal clear. In 1908, the city applied for development rights to dam the Tuolumne River at the most ideal spot (as far as engineers were concerned): the Hetch Hetchy Valley.

The U-shaped valley with its hard-to-erode granite walls and natural narrowing gave it the potential to store 117 billion gallons of pure Sierra snowmelt. Muir and his conservation organization, the Sierra Club, fought ardently against the damming of one of his favorite spots in the world.

“Dam Hetch Hetchy?” said Muir. “As well dam for water-tanks the people’s cathedrals and churches, for no holier temple has ever been consecrated by the heart of man.”

The fight that’s been credited with starting the environmental movement ultimately failed when, in 1913, Congress signed the Raker Act allowing a single city to dam a river on federal land for its individual use. The O’Shaughnessy Dam was completed in 1918 and the valley was completely flooded by 1923.

Three years after the Raker Act was passed, President Wilson signed the National Park Service Organic Act giving the newly created National Park Service the purpose “to conserve the scenery and the natural and historic objects and the wild life therein and to provide for the enjoyment of the same in such manner and by such means as will leave them unimpaired for the enjoyment of future generations.”

While it was too late for Hetch Hetchy, the new act would safeguard other national parks from similar fates.

In the hundred years that have passed since the reservoir’s completion, water in the Bay-Delta (the official name for the watershed encompassing all the rivers that feed into the San Francisco Bay from the Sacramento River in the north to the San Joaquin River in the south) hasn’t lost its controversy.

Water aqueduct map from Hetch Hetchy Reservoir to San Francisco
Water aqueduct map from Hetch Hetchy Reservoir to San Francisco. Click to see larger image. (Photo: Wikimedia Commons/Shannon1)

The 2020-2022 water years (which ended Sept. 30, 2022) were the three driest years on record for the state of California and the term “mega-drought” has become common-place. While the dialogue around the West’s water wars has been concentrated on the Colorado River and the alarming decline of Lake Powell and Lake Mead, watersheds across the Western United States are feeling the effects of a rapidly aridifying landscape due to climate change. As of October 2022, Hetch Hetchy was at 77.5% of its capacity.

The Fight for the Bay-Delta

One example of these controversies is the current proposal for the Delta Conveyance Project for the California State Water Project that would build a tunnel diverting millions of acre-feet of fresh water from the Sacramento River in the north near the communities of Clarksburg, Hood and Courtland and carry it to the Bethany Reservoir, southeast of Stockton.

Two-thirds of the state of California’s water originates in the Sierra Nevada mountains as snow and flows through a network of rivers, crossing the Bay-Delta through natural channels to provide water to California residents and farmlands.

The main reasoning behind this project, according to the California Department of Water Resources, is that the current system of relying on the natural channels is vulnerable to earthquakes and sea level rise. The department is concerned that aging infrastructure could pose threats to the state’s water system should a natural disaster strike, or in the face of worsening climate change.

A tunnel, however, would mean that millions of acre-feet of that fresh Sierra Nevada snowmelt wouldn’t flow through the Bay-Delta.

The Bay-Delta is a beautiful and complex ecosystem that is vital to many species of fish, birds and other wildlife as well as local communities. The 700 miles of sloughs, marshes and waterways support migration, local recreation and is the life-blood for many communities.

Bay-Delta near San Francisco
Bay-Delta near San Francisco (Photo: by Jane Tyska/Digital First Media/The Mercury News via Getty Images)

The endangered Chinook salmon uses the Bay-Delta’s waterways to spawn and migrating birds, such as Sandhill Cranes, spend their winters in the area. Multi-generational family farms rely on the delta to water their crops and the waterways and wetlands provide recreational opportunities for the area’s residents, most of which are minorities. In the 2020 Census, 72.3% of San Joaquin County residents identified as non-white.

When snowpack is low, which it has been in the past few drought-stricken years, water flows are also low. These low freshwater flows allow for increased salt water to enter and damage or destroy ecosystems. These low flows also cause shallower water, which warms up faster and causes toxic algal blooms which pollute the waterways, killing fish and wildlife and making people and pets sick who come into contact with the tainted water. A University of Michigan study also found that algal blooms can enter the air, causing not only water pollution but air pollution.

The proposed tunnel would only further restrict fresh water flows to the Bay-Delta, intensifying the effects of climate change.

Caleen Sisk, Chief and Spiritual leader of the Winnemem Wintu Tribe, joined a crowd gathered on the steps of the State Capitol building to show their opposition to the Bay Delta Conservation Plan in 2012.
Caleen Sisk, Chief and Spiritual leader of the Winnemem Wintu Tribe, joined a crowd gathered on the steps of the State Capitol building to show their opposition to the Bay Delta Conservation Plan in 2012. (Photo: By Michael Macor/The San Francisco Chronicle via Getty Images)

While water security is a heavy topic to weigh against environmental issues, the Sierra Club argues that the Delta Conveyance Project isn’t just a bad idea for the humans and ecosystems of the Bay-Delta. They argue that it also isn’t a solution to the infrastructure problem the area faces which triggered the proposal in the first place.

“The project is currently estimated to cost $16 billion so it’s very expensive and we argue that, for this high cost of a project, it’s unlikely to deliver what it proposes to deliver,” says Sierra Club California conservation coordinator Molly Culton. “It won’t be completed until 2040 so it wouldn’t meet our water needs right now and it wouldn’t create new water.”

Instead of the costly project that the club argues against, their proposed plan includes local and regional solutions like stormwater capture, groundwater recharge, conservation and efficiency measures and water recycling, as well as funding to repair aging infrastructure like levees.

“The California State Water Project argues that the tunnel will help protect the Project from seismic risk, but it’s just one part of the Project,” argues Culton. “All the other infrastructure isn’t proposed to be updated or retrofitted. So there will still be weaknesses in the Project.”

As of October 2022, a draft Environmental Impact Report was out for comment on the tunnel. After the comment period closes, a final report will be issued mid-2023 to decide the project’s fate. California Representative Josh Harder introduced a bill to stop the tunnel at the federal level in September 2022.

Other Battles in the Water Wars

The Delta Conveyance Project is just one way central California is feeling the squeeze when it comes to water. Along the Tuolumne River, which is controlled by the O’Shaughnessy Dam, the Tuolumne River Trust is fighting for higher in-stream flows to support a struggling ecosystem, including dwindling salmon populations.

In Yosemite, an ambitious group called “Restore Hetch Hetchy” continues John Muir’s fight against the dam and calls for its removal.

One hundred years later and California is no closer to solving its water issues. As we look towards a future where climate change continues to intensify, Sierra Nevada snowpack will certainly remain at the heart of water debates in central California.

To learn more about the Delta Conveyance Project and to sign the Sierra Club petition against it if you live in California, visit