The Chelan River is a tributary of the Columbia River, in the U.S. state of Washington. Just 4.1 miles (6.6 km) long, it is the shortest river in Washington.[1]Lake Chelan Dam is located at the river's source: the outlet of Lake Chelan. Nearly the entire river's flow is diverted to the Lake Chelan Powerhouse, 3.9 miles (6.3 km) downstream near the river's mouth. Thus the Chelan River is almost always dry. Statistics on the streamflow are taken at the tailrace of the powerhouse, measuring the water that would flow through the river were it not diverted.[2]