Lake Washington Ship Canal begun in 1906, and work began in earnest five years later. The delays in canal planning and construction resulted in the U.S. Navy building the Puget Sound Naval Shipyard in Bremerton, Washington, which is located across the Sound from Seattle. For centuries, people had been dragging boats between the lakes, giving names like "carry a canoe" "sxWátSadweehL" to the crossing points. In 1854 Seattle pioneer Thomas Mercer proposed canals connecting Lake Union and Lake Washington to Puget Sound in a speech at the first Independence Day celebration of the Seattle area's first permanent white settlement, shortly after its founding. Mercer
Lake Washington is now the primary source of water for Lake Washington. In addition, there are numerous small creeks and rivers which feed the lake, including: Before construction of the Lake Washington Ship Canal in 1916, Lake Washington's outlet was the Black River, which joined the Duwamish River and emptied into Elliott Bay. When the canal was opened the level of the lake dropped nearly nine feet (2.7 m). The canal to the Puget Sound became the lake's sole outlet, causing the Black River to dry up and disappear. Concrete floating bridges are employed to span the lake because Lake Washington's depth