Restore Hetch Hetchy: Reclaiming a Natural Splendor While Preventing Global Warming

Hetch Hetchy reservoir - Kolana Rock on the right side

For nearly 100 years now, the Hetch Hetchy Valley in Yosemite National Park has been submerged under 300 feet of water. However, Restore Hetch Hetchy, a non-profit organization created by the Sierra Club in 1999, has set their sights on restoring the valley to its original condition.

In 1913, after a long debate in congress, the Raker Act was signed, authorizing the creation of the O’Shaughnessy Dam and the Hetch Hetchy Reservoir, for the purposes of providing water to the city of San Francisco. The dam, which blocks the flow of the Tuolumne River, was completed 10 years later.

Today, Hetch Hetchy is the largest of 9 reservoirs that store water for San Francisco. But, were the Hetch Hetchy Valley to be restored, San Francisco could continue to maintain its current supply of water by storing the water from the Tuolumne River further downstream.

While San Franciscans may be concerned that restoring the valley and draining the reservoir is a daunting and risky task, the benefits of completing such a project are vast. First, Yosemite National Park could be returned to its natural splendor in its entirety, generating large increases in revenue as a result. Next, recent studies suggest that the project could be completed without any significant decrease in San Francisco’s water supply, and would even provide cleaner water to the city, as the production of a new filtration system would be necessary. Lastly, restoring the meadows and trees that once flourished in the Hetch Hetchy Valley could help kick off trend of habitat restoration that will be essential for the prevention of global warming.

Current predictions estimate temperature increases of 3-9 degrees Fahrenheit over the next 100 years. In addition, sea levels are expected to rise 1-2 feet over the same time frame. With little progress made on the reduction of fossil fuel emissions, habitat restoration is a viable and practical solution for slowing global warming. Habitat destruction, like the flooding of the Hetch Hetchy Valley, is the cause of a quarter of global warming due to human activity, twice as much as effects from transportation and industry. In addition, a restored valley would not only eliminate the current methane emissions of the reservoir, but also act as a carbon sink for over 6,000 metric tons of carbon a year, enough to offset 5 months of emissions from the Caltrain system.

Last month, Turlock and Modesto Counties, which receive their water from the Don Pedro Reservoir further down the Tuolumne River, applied to renew the license of the Don Pedro Dam, due to expire in 2016. Restore Hetch Hetchy argues that because San Francisco trades water with Turlock and Modesto by releasing water from Hetch Hetchy downstream, in exchange for water in drought years, the two reservoirs function as part of a system. If the Federal Environmental Regulatory Commission (FERC), which is set to decide whether or not Don Pedro will be relicensed, determines that the two reservoirs are linked, an assessment of the environmental impacts of the dams must be completed under the National Environmental Policy Act. This analysis in turn could expedite the process of approving the restoration of the Hetch Hetchy Valley.

Ultimately, restoring the Hetch Hetchy Valley would have an ecological impact that would be felt for many years, providing more beauty for the visitors to Yosemite National Park while helping combat global warming. Restore Hetch Hetchy is hopeful that approval for the restoration of the valley can be achieved by 2012, and resources could be allocated for the restoration by 2014, the 100th anniversary of John Muir’s death.

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