Dry Falls

fossil waterfall, United States

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June 25, 2026

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Dry Falls, located in the Columbia River Plateau of Washington, United States, is a "fossil waterfall" that formed during the late Pleistocene epoch. It was created when a massive ice sheet blocked and diverted the Columbia River, forming a large glacial lake. As the ice dams periodically failed, torrents of water were released, carving a canyon nearly 300 meters deep. Dry Falls, approximately 120 meters high and five kilometers wide, marks a significant point along this ancient flow path. The Columbia River has since reestablished its original course, leaving the falls dry today.1

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Falls attributable to constructional processes
…the most interesting examples is Dry Falls, a “fossil waterfall” in the Columbia River Plateau, Washington, which formed in late Pleistocene time. A large ice sheet blocked and diverted the then-westward-flowing Columbia River and formed a vast glacial lake. The lake drained to the south when permitted to do so…
Read More
…the most interesting examples is Dry Falls, a “fossil waterfall” in the Columbia River Plateau, Washington, which formed in late Pleistocene time. A large ice sheet blocked and diverted the then-westward-flowing Columbia River and formed a vast glacial lake. The lake drained to the south when permitted to do so…
Read More