Lake Washington Ship Canal

The Lake Washington Ship Canal, which runs through the city of Seattle, connects the fresh water body of Lake Washington with the salt water inland sea of Puget Sound. The Hiram M. Chittenden Locks accommodate the approximately 20-foot difference in water level between Lake Washington and the sound. The canal runs east–west and connects Union Bay, the Montlake Cut, Portage Bay, Lake Union, the Fremont Cut, Salmon Bay, and Shilshole Bay, which is part of the sound.

The ship canal project began in 1911 and was officially completed in 1934. Prior to construction of the Lake Washington Ship Canal, otherwise known as the Salmon Bay Waterway, water used to exit Lake Washington via the Black River which flowed from the south end of Lake Washington into the Duwamish River.

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