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Hydrology of Yosemite National Park

By Geology and Ecology of National Parks

Learn more about the hydrology of Yosemite National Park.

Hydrology of Yosemite National Park

Hydrology is the study of water and its interaction with the landscape. Water has shaped the dramatic formations of Yosemite for millions of years and can be seen today in its famous lakes and waterfalls. The amount of water influences the ecology of Yosemite in the meadows and in the giant sequoia groves. Yosemite National Park’s hydrology program includes the National Park Service, the USGS, the Merced Irrigation District, and Hetch Hetchy Water and Power. Together they monitor water quality and quantity. Their research helps to understand hydrologic trends and ecological impacts and provides hydrologic data to the decision-makers responsible for resource management within the park.

Image: Yosemite Falls-All Three Sections
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Yosemite Falls is the highest measured waterfall in North America and one of the most famous waterfalls within Yosemite National Park. Water influences the geology and ecology of the park.
Former Yosemite Happy Isles Streamgage.
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Former Yosemite Happy Isles Streamgage.

Most precipitation in Yosemite National Park falls as snow that accumulates above ~6,000 feet during the winter months. This snowpack is an important freshwater resource sustaining biologically-rich areas downstream when the snow melts, including meadows, alpine meadows, and the plants and animals that live there.