Was connecting Lake Washington to Puget Sound just a pipe dream? Not anymore. We are standing before the Lake Washington Ship Canal. It is an eight-mile waterway. The Lake Washington Ship Canal connects Lake Washington to Puget Sound. This allows boats to travel between fresh and salt water.
Imagine Seattle before the Lake Washington Ship Canal. Water flowed out of Lake Washington via the Black River. The Black River flowed into the Duwamish River.
The idea for a canal emerged in 1854. Thomas Mercer proposed connecting Lake Washington and Puget Sound. His goal was to transport logs and lumber. The U.S. Navy supported the canal project. They planned to build a naval shipyard on Lake Washington. The U.S. Army Corps of Engineers began planning in 1891.
Delays plagued the project. The Navy built the Puget Sound Naval Shipyard in Bremerton. This shipyard is across the Sound from Seattle.
Centuries ago people dragged boats between the lakes. They called these crossing points “carry a canoe”. Thomas Mercer named Lake Union and Lake Washington. Lake Union suggested canals merging waters. Lake Washington honored George Washington.
Harvey L. Pike tried to dig a ditch himself in 1860. He wanted to transport logs between Portage Bay and Union Bay. He hoped to increase his property value. Pike joined Thomas Burke and Daniel Gilman. They formed the Lake Washington Canal Company in 1871. Instead of a canal they built a tramway.
The Army Corps of Engineers favored Lake Washington for a naval base. It offered secure waters and fresh water. It was also close to coal and timber. General Alexander had serious objections to the Shilshole Bay route. He cited expense and the need for dredging. He also thought the canal would be less defensible in wartime.
Congress directed a study for a canal and lock system in 1902. They examined routes via Shilshole Bay and Smith Cove. No one attended the public meeting.
James A. Moore proposed a canal with wooden locks in 1906. Hiram M. Chittenden became the new Army District Engineer. Chittenden found Moore’s plan too modest and potentially unsafe. He proposed a double concrete lock with steel gates.
Chittenden had to sway local leaders away from Moore’s project. Moore transferred his rights to the Lake Washington Canal Association in 1907. Chittenden retired in 1909 but continued lobbying for the project.
Congress appropriated funds in 1910. Construction of the locks began November 10, 1911. The locks closed in July 1912. Salmon Bay became freshwater. A temporary dam at Montlake breached in 1916. The Ballard Locks officially opened for boat traffic May 8, 1917. The Lake Washington Ship Canal was complete in 1934. The Government Locks were renamed in memory of Chittenden in 1956.
Before the Lake Washington Ship Canal construction, water exited Lake Washington via the Black River into the Duwamish River.
Navigation starts at Webster Point in Lake Washington. It continues to Shilshole Bay. The speed limit is seven knots. It is 2.5 knots when entering and exiting the locks.
During heavy rain, stormwater and wastewater dump into the canal. The EPA and Washington State ordered Seattle to address the issue. A diversion system is planned. It will use a tunnel to divert wastewater to a treatment plant. Construction on the tunnel began in June 2021.
The Lake Washington Ship Canal’s crossings include the Montlake Bridge. It also include the University Bridge and the Fremont Bridge.
The Lake Washington Ship Canal and the Chittenden Locks are on the National Register of Historic Places. The Montlake Cut and Bridge are Seattle Designated Landmarks.
The Lake Washington Ship Canal’s opening celebration was July 4, 1917. Thomas Mercer proposed the idea 63 years prior. It took five decades to decide where to build it and how to pay for it. Hiram M. Chittenden took over the Seattle District of the Army Corps of Engineers in 1906.
The Fremont Cut is between Salmon Bay and Lake Union. The Montlake Cut is between Lake Union and Lake Washington. The canal’s construction lowered Lake Washington by nine feet. It raised Salmon Bay. Salmon Bay changed from a tidal inlet to a freshwater reservoir.