The Hetch Hetchy Power System generates hydroelectric power for the Bay Area that is 100% free of greenhouse gases. The system generates clean electricity and transmits it through a system of high tension power transmission lines from the Sierras across the Central Valley to San Francisco.
ENGEO has served the project for over 15 years and is proud to play a part in providing Californians with a source of clean energy.
Our recent and ongoing role on the Hetch Hetchy Water and Power’s (HHWP’s) power system spans Alameda, San Joaquin, Stanislaus and Tuolumne Counties in California, wherein we support HHWP’s Transmission Line Clearance Mitigation Program which aims at mitigating ground, wire, and structure clearance issues with Hetch Hetchy Water and Power high voltage power lines in accordance with the SFPUC’s mitigation program. Such modifications may alter the structural loading of the towers possibly necessitating modification or retrofit to existing transmission tower foundations, or relocation and construction of new towers. Our role included several aspects of geotechnical and geologic engineering such as investigations to characterize the rockfall and slope stability hazards using a combination of geologic mapping, geophysical methods, and geotechnical drilling, and to provide recommendations for relocation of the towers to minimize future rockfall hazard.