The Lake Washington Ship Canal is a canal that runs through the city of Seattle and links the fresh water body of Lake Washington with the salt water inland sea of Puget Sound. The Hiram M. Chittenden Locks accommodate the approximately 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.

History

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.

As early as 1854, there was discussion of building a navigable connection between Lake Washington and Puget Sound for the purpose of transporting logs, milled lumber, and fishing vessels. Thirteen years later, the United States Navy endorsed a canal project, which included a plan for building a naval shipyard on Lake Washington. In 1891 the US Army Corps of Engineers started planning the project. Some preliminary work was 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.

Early efforts

For centuries, people had been dragging boats between the lakes, giving names like "carry a canoe" sxWátSadweehL to the crossing points. The system will use a tunnel running along the north side of the canal with access stations at five sites in Fremont, northern Queen Anne, and Ballard before reaching a pump station, where wastewater can continue to the West Point sewage treatment plant.

The project is expected to cost $570 million to construct, with 65 percent of funding sourced from Seattle Public Utilities and the remaining 35 percent from the King County government. Tunnel boring from Ballard to Wallingford was completed in June 2023 and construction is scheduled to be completed in 2026.

Canal crossings

thumb|Looking the opposite direction, the [[Ballard Bridge and, at top of frame, Northern Pacific Railroad Ship Canal Bridge (bascule bridge, open here), 1950.]]

The Canal's crossings, from east to west, are:

  • the University Link Tunnel carrying Link light rail under the canal
  • the Montlake Bridge carrying State Route 513 (Montlake Boulevard NE) over the Montlake Cut
  • the University Bridge carrying Eastlake Avenue over Portage Bay
  • the Ship Canal Bridge carrying Interstate 5 over Portage Bay
  • the George Washington Memorial Bridge (commonly called the Aurora Bridge) carrying Aurora Avenue N. (State Route 99) over the west end of Lake Union
  • the Fremont Bridge connecting 4th Avenue N. to Fremont Avenue N. over the Fremont Cut
  • Northern Pacific Railroad Ship Canal Bridge near the west end of the Fremont Cut 1914–1976, no longer extant.
  • the Ballard Bridge carrying 15th Avenue over Salmon Bay
  • pedestrian crossing only at the Hiram M. Chittenden Locks
  • the BNSF Railway's Salmon Bay Bridge over Salmon Bay

An additional crossing for transit, bicycles, and pedestrians between the Ballard and Fremont bridges was proposed by Mayor Mike McGinn in 2012, but funding to study its feasibility were rejected by the Seattle City Council. A new Link light rail crossing, carrying the Ballard Link Extension near the existing Ballard Bridge, is planned to be constructed in the 2030s.

Seattle landmarks

The Lake Washington Ship Canal and the Hiram M. Chittenden Locks are listed on the National Register of Historic Places. The Montlake Cut, along with the Montlake Bridge are City of Seattle Designated Landmarks (ID #107995).

Notes

  • Lake Washington Ship Canal and Hiram M. Chittenden Locks from U.S. Army Corps of Engineers