Restore Hetch Hetchy

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Restoration Studies

We present here a number of the recent studies which show in a preliminary way that it is possible to retore Hetch Hetchy while still providing water to the San Francisco Bay Area. Restore Hetch Hetchy is pleased that all of these studies have been completed, and we continue to advocate the completion of a much more thorough, independent and comprehensive analysis of Hetch Hetchy restoration options.

Restore Hetch Hetchy has issued a preliminary Response to the State of California Hetch Hetchy Restoration Study. See also our 2005 report below. (July 19, 2006)
Hetch Hetchy Informational Hearing (Windows Media)
Watch the complete three-hour October 10, 2006 Hetch Hetchy Informational Hearing held by the California Assembly Standing Committee on Water, Parks & Wildlife, webcast archive by The California Channel.
California Resources Agency - Hetch Hetchy Restoration Study.
The Resources Agency has conducted a review of existing studies concerning the potential for restoring Hetch hetchy while replacing the water supply. The report concluded that "the existing body of work — including its own — is insufficient to support sound public policy decision-making at this time; in fact, most of the work to date is not even at the 'concept level.' However, the state found no fatal flaws in the restoration concept that would preclude additional study. Future studies of Hetch Hetchy restoration should be completed with well-defined objectives, supported by a robust stakeholder process. Moreover, studies should be carried out to a consistent level across all issues, beginning with benefits, public use in a restored Hetch Hetchy Valley, and dam removal." (2006)

Restore Hetch Hetchy - Feasibility Study 2005 - Finding the Way Back to Hetch Hetchy Valley: A Vision of Steps to Restore Hetch Hetchy Valley in Yosemite National Park and to Replace Water and Energy Supplies (September 13, 2005) This major new study reveals that practical, reasonably priced solutions exist which can easily replace the water and energy that would otherwise be lost if O’Shaughnessy Dam were removed and Yosemite’s Hetch Hetchy Valley were restored.
- Press Release Summarizing the Report: HTML - PDF
- Executive Summary (1.3 MB Download - PDF - Executive Summary)
- Full Report (Caution! Large File! - 18.MB - Download - PDF)
- Order Report on CD
(September 13, 2005).
Environmental Defense, Paradise Regained: Solutions for Restoring Yosemite's Hetch Hetchy Valley (2004) (Off-site link) Authors: Spreck Rosekrans, Economic Analyst; Nancy Ryan, Economist; Ann Hayden, Water Resource Analyst; Thomas Graff, Regional Director; John Balbus, Senior Scientist, Program Director.
A new report detailing how, with the removal of the dam, Hetch Hetchy Valley could be restored to its former glory. This analysis, the most in-depth study conducted to date, finds there are cost-effective engineering solutions that would continue to supply the Bay Area with the same high-quality drinking water from the Tuolumne River while returning Hetch Hetchy to Yosemite National Park.
Null, Sarah, Re-Assembling Hetch Hetchy: Water Supply Implications of Removing O'Shaughnessy Dam (2003) (Masters Thesis) (Off-site link) (PDF) (1.3 MB)
Examines water supply impacts, economics, and options for removing O'Shaughnessy Dam. This study used the CALVIN computer model (California Value Integrated Network) developed at UC Davis by Dr. Jay Lund, a recognized water expert in California. Above link will download full text from the University of California, Department of Civil and Environmental Engineering, Statewide Economic-Engineering Water Model - CALVIN.
Abstract: The Hetch Hetchy System provides San Francisco with much of its water supply. O’Shaughnessy Dam is one component of this system, providing approximately 25% of water storage for the Hetch Hetchy System and none of its conveyance. Removing O’Shaughnessy Dam has gained interest for restoring Hetch Hetchy Valley. Removal would entail reoperating other existing reservoirs for water storage, but would open the valley to restoration, revenue, and economic development from recreation and tourism. The water supply feasibility of removing O’Shaughnessy Dam is analyzed by examining alternative water storage and delivery operations for San Francisco using an economic-engineering optimization model. The economic benefits of O’Shaughnessy Dam, and its alternatives are measured in terms of the quantity of water supplied to San Francisco, economic costs, and hydropower generation.
National Park Service, Alternatives For Restoration Of Hetch Hetchy Valley Following Removal Of The Dam And Reservoir (1988) (PDF) (48 K), 18 pp.
Evaluates restoration alternatives for recovery, using no management, moderate management, and intensive management.
U.S. Bureau of Reclamation, Hetch Hetchy: Water and Power Replacement Concepts (February, 1988).
Executive Summary (PDF - 683 K), 18 pp.
Full Report (excluding Appendix) (PDF - 2.10 MB), 56 pp.
Appendix. (PDF - 2.3 MB), 43 pp.
Concludes in a preliminary way, with further study required, that, even without the O'Shaugnessy Dam, the Tuolumne River could provide enough water to San Francisco to operate the city's existing conveyence system at full capacity and deliver almost 100,000 acre-feet more than is currently being used.

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To get involved in the effort to restore Hetch Hetchy, contact Restore Hetch Hetchy at: info@hetchhetchy.org, P.O. Box 3538, Sonora, CA 95370. Telephone: (209) 533-4481.

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