Final answer:
The Hetch Hetchy Valley in Yosemite National Park was turned into a reservoir to provide water for San Francisco after the 1906 earthquake, despite opposition from conservationists.
Step-by-step explanation:
The location in Yosemite Park that was once a beautiful U-shaped valley and is now a reservoir is the Hetch Hetchy Valley. In 1913, a conflict arose between those who held an anthropocentric view, believing the land should be used to benefit humans, and those with a biocentric ethic, emphasizing the importance of preserving nature. The valley was eventually dammed to provide a stable supply of water to San Francisco after the 1906 San Francisco earthquake, which resulted in devastating fires.
Despite opposition led by John Muir and the Sierra Club, arguing that the reservoir would be a disaster for the ecology of Central California, the dam was supported by Gifford Pinchot and President Theodore Roosevelt. The construction of the Hetch Hetchy Reservoir was completed by 1923, demonstrating a significant event where conservation ideals were overruled by the perceived needs of a growing city.