- The Wenatchee River is a river in the U.S. state of Washington, originating at Lake Wenatchee and flowing southeast for 53 miles (85 km), emptying into the Columbia River immediately north of Wenatchee, Washington. On its way it passes the towns of Plain, Leavenworth, Peshastin, Dryden, Cashmere, Monitor, and Wenatchee, all within Chelan County. The river attracts kayaking and river rafting enthusiasts and tourism.