Flood of Change

At the end of the last Ice Age, about 18,000 to 15,000 years ago, an ice dam in northern Idaho created Glacial Lake Missoula in Montana. The ice dam burst and released flood waters across Washington and down the Columbia River back flooding into Oregon before eventually reaching the Pacific Ocean. Happening perhaps a 100 times. Forever changing the lives and landscape of the Pacific Northwest.

NASA graphic image showing the landscape impacted by the floods

Ice Age Floods National Geologic Trial

NASA helps us see the landscape impacted by the floods.

This is a graphic representation of where the flood waters went.

Washington Geological Survey Floods Map

Washington Geological Survey/Washington State DNR

Last updated: May 24, 2021

Contact the Park

Mailing Address:

Program Manager
Ice Age Floods National Geologic Trail
1008 Crest Drive

Coulee Dam, WA 99116


(509) 237-9722

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