Near Groveland in Tuolumne County, California — The American West (Pacific Coastal)
Producing Clean Renewable Energy
Early Intake Powerhouse was built in 1918, twelve miles downstream from OShaughnessy Dam. It supplied power for the tools and equipment used in building the dam. It also powered lighting for nighttime construction - a visionary innovation at the time.
Moccasin Powerhouse was built in 1925; Holm and Kirkwood Powerhouses were built decades later to increase power generation capacity.
Hydropower from the Hetch Hetchy Water and Power Project supplies electricity to the Modesto and Turlock Irrigation Districts, in accordance with the Federal Raker Act, and to San Francisco for the airport, hospitals, libraries, schools, streetlights, electric buses and other municipal facilities.
(caption) San Francisco City Hall, San Francisco General Hospital and non-polluting electric railcars use renewable energy from the Hetch Hetchy Water and Power Project.
(caption) Early Intake Powerhouse, completed in 1918, provided a dependable source of clean power at the beginning of the Hetch Hetchy Water and Power Project construction.
(caption) Worker next to a Pelton Wheel, one of the most efficient water turbines for producing hydropower.
(inset diagram captions) Reservoir // A penstock is a pipeline or tunnel which delivers water from a higher elevation to the turbines located at the powerhouse. // A Pelton turbine is turned by the force of the water on their cups. // Generators are rotated by the turbines to generate electricity. // Transmission lines conduct electricity to the cities.
Topics. This historical marker is listed in these topic lists: Industry & Commerce • Natural Resources. A significant historical year for this entry is 1918.
Location. 37° 56.859′ N, 119° 47.273′ W. Marker is near Groveland, California, in Tuolumne County. It can be reached from Hetch Hetchy Road. Touch for map. Marker is in this post office area: Groveland CA 95321, United States of America. Touch for directions.
Regionally, this marker is in California’s Sierra Nevada. It is also in the American Mountain West. Globally, it is in North America, on the Ring of Fire, in the Pacific Rim, in the Western Hemisphere, in the Western World, and in the Anglosphere. Historically, it finds itself in what was once New Spain and also Mexicos Alta California.
Other nearby markers. At least 8 other markers are within 18 miles of this marker, measured as the crow flies: OShaughnessy Dam (here, next to this marker); Hetch Hetchy Reservoir and OShaughnessy Dam (here, next to this marker); Water Quality at Hetch Hetchy (here, next to this marker); Trails and Waterfalls (here, next to this marker); Hetch Hetchy Railroad (here, next to this marker); John Muir... The Woodcutter (approx. 17.3 miles away); The Ahwahneechee (approx. 17.4 miles away); James Hutchings (approx. 17½ miles away). Touch for a list and map of all markers in Groveland.
Credits. This page was last revised on June 16, 2016. It was originally submitted on July 29, 2007, by Karen Key of Sacramento, California. This page has been viewed 1,612 times since then and 26 times this year. Photos: 1, 2, 3. submitted on July 29, 2007, by Karen Key of Sacramento, California. • J. J. Prats was the editor who published this page.


