The Black River was a river in King County in the U.S. state of Washington. It drained Lake Washington until 1916 when the opening of the Lake Washington Ship Canal lowered the lake, causing the Black River to dry up. It still exists as a short dammed stream about 4000 feet (1200 m) long,[1] draining some wetlands into the Duwamish River between Tukwila and Renton, just northeast of the I-5 and I-405 interchange.[2]