What is the tallest dam in the united states of america?

The 770 ft.-tall Oroville Dam in Northern California is the tallest in the U. S., holding back the force of 3.5 million acre-feet of water.

Oroville Dam is an earthfill embankment dam on the Feather River east of the city of Oroville, California, in the Sierra Nevada foothills east of the Sacramento Valley. At 770 feet (235 m) high, it is the tallest dam in the U. S.[8] and serves mainly for water supply, hydroelectricity generation and flood control.

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