Black River

The Black River is a tributary of the Duwamish 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 part of the Black River to dry up. It still exists as a dammed stream about 2 miles long.
Before the 20th century, Lake Washington emptied from its south end into the Black River, which was joined by the Cedar River before meeting the White River . The confluence of the Black and White rivers created the Duwamish River, which emptied into Elliott Bay in Puget Sound. Thus, the water of rivers emptying into Lake Washington, such as the Sammamish River, once flowed through the Black and Duwamish rivers. Today, Lake Washington's water empties into Puget Sound via the Lake Washington Ship Canal.

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