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Geological Formation

Hetch Hetchy

Valleys

Hetch Hetchy is a glacially carved valley in the northwestern section of Yosemite National Park in California, drained by the Tuolumne River. The valley floor sits at about 3,783 feet in elevation and once ran roughly 3 miles long and half a mile wide, similar in character to the nearby Yosemite Valley. Native Americans inhabited and managed the valley for millennia before American settlement in the 1850s. In 1913 Congress authorized a dam across the valley, and the O'Shaughnessy Dam, completed in 1923, submerged the valley floor to create a reservoir that has supplied water to San Francisco and the Bay Area since 1934.

Facts
Classification
Protected Status
National Park or Reserve 1
Connections

Caused By

Erosion, Processes

Wikidata P31 formation-type mapped to formative process Erosion via reviewed judgment map (earth atlas); source citation is this entity's own cited Wikidata item.

Source Wikidata: Hetch Hetchy
Glaciation, Processes
Source Hetch Hetchy (Wikipedia)

In Discipline

Geomorphology, Disciplines

Wikidata P31 formation-type mapped to discipline Geomorphology via reviewed judgment map (earth atlas); source citation is this entity's own cited Wikidata item.

Source Wikidata: Hetch Hetchy
In the Other Atlases

Found In

United States

Also in Geography Atlas: where this subject is found.

Source Wikidata: Hetch Hetchy
Sources
1. Hetch Hetchy (Wikipedia)
  • Lead section
    Hetch Hetchy is a valley, reservoir, and water system in California in the United States.
  • Article text
    The glacial Hetch Hetchy Valley lies in the northwestern part of Yosemite National Park and is drained by the Tuolumne River.
  • Caused By: Glaciation, Article text, process Glaciation
    During the last glacial period, the Tioga Glacier formed from extensive icefields in the upper Tuolumne River watershed; between 110,000 and 10,000 years ago Hetch Hetchy Valley was sculpted into its present shape by repeated advance and retreat of the ice, which also removed extensive talus deposits that may have accumulated in the valley since the Sherwin period.
View the Source
Wikidata: Hetch Hetchy
Wikidata Q1616130, class allow-list match (w-wdresolver-0926)View the Source
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