In 1914 Congress approved the Raker Act, allowing San Francisco to construct a dam and reservoir in the Hetch Hetchy Valley of Yosemite National Park for the purpose of public water supply.
The Moccasin Creek Fish Hatchery was constructed downstream of the dam in 1954,[REF] and raises trout for stocking in high elevation streams in the Tuolumne River watershed, and for the nearby, much larger Lake Don Pedro [REF].