Hetch Hetchy Communications System Project

Hetch Hetchy Reservoir with granite walls in view

Hetch Hetchy Water and Power (HHW&P), a division of the City and County of San Francisco Public Utilities Commission (SFPUC), manages a complex utilities system which provides drinking water to Groveland, the City of San Francisco, and several Bay Area counties, as well as hydroelectric power for San Francisco municipal uses, for sale to irrigation districts, and for sale to other utilities. HHW&P utilizes communication equipment at O’Shaughnessy Dam, in the Hetch Hetchy area of Yosemite National Park, in support of their operation.

The former equipment, utilized existing phone lines, transmitted voice and data communications essential to the operation and security of HHW&P’s electric and water supply utilities, and was also used by Yosemite personnel for park communications. The radio and fiber optic equipment was obsolete and no longer supported by their manufacturers. A system upgrade was needed to improve radio communication vital to park operational activities, such as law enforcement, search and rescue, and fire management. Additionally, it would improve the capability to ensure dam security, visitor and staff safety, and protection of park resources. This project ultimately updated the infrastructure by replacing or updating components of the communication system throughout Tuolumne County, including adding one new site within Yosemite National Park.

The collective input of Hetch Hetchy Water and Power, Yosemite National Park, and the public helped determine the most appropriate location for this proposed project within the Hetch Hetchy region. The site chosen for this project:

  • Is outside of Yosemite National Park Wilderness Area
  • Has line- of- sight visibility to O’Shaughnessy Dam and the communication tower on Burnout Ridge
  • Has limited visibility from locations viewed by the public
  • Is relatively close to an exiting electrical distribution line to avoid the need for further infrastructure
  • Is close to an existing road and turnout to allow for easy maintenance access
  • Is an area large enough for a communications tower and equipment shelter

Public and internal scoping for this project occurred in spring 2006. Based on the input, the project team selected two locations within Yosemite for further analysis as potential tower locations in the EA/IS. Both of these sites are located outside of Wilderness boundaries. A final document and Finding of No Significant Impact was completed in 2008.



Finding of No Significant Action

Environmental Assessment

Public Scoping

Last updated: September 20, 2022

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