Construction of the Lake Washington Ship Canal and Hiram M. Chittenden Locks was completed in 1917 by the U.S. Army Corps of Engineers. Connecting the waters of Lake Washington, Lake Union, and Salmon Bay to the tidal waters of Puget Sound, the canal and locks allow recreational and commercial vessels to travel to the docks and warehouses of Seattle's busy freshwater harbor.

The complex of locks sits in the middle of Salmon Bay and are part of Seattle's Lake Washington Ship Canal. They are known locally as the Ballard Locks after the neighborhood to their north. (Magnolia lies to the south.)

The locks and associated facilities serve three purposes:

• To maintain the water level of the freshwater Lake Washington and Lake Union at 20 to 22 feet above sea level.
• To prevent the mixing of sea water from Puget Sound with the fresh water of the lakes (saltwater intrusion).
• To move boats from the water level of the lakes to the water level of Puget Sound, and vice versa.

The complex includes two locks, a small (30 x 150 ft, 8.5 x 45.7 meter) and a large (80 x 825, 24.4 x 251.5 meter). The complex also includes a (235-foot, 71.6 meter) spillway with six (32 x 12-foot (3.7 m), 9.8 x 3.7 meter) gates to assist in water-level control. A fish ladder is integrated into the locks for migration of anadromous fish, notably salmon.

The grounds feature a visitors' center, as well as the Carl S. English, Jr. Botanical Gardens.

Operated by the U.S. Army Corps of Engineers, the locks were formally opened on July 4, 1917, although the first ship passed on August 3, 1916. They were named after U.S. Army Major Hiram Martin Chittenden, the Seattle District Engineer for the Corps of Engineers from April 1906 to September 1908.

In 1978, the locks were added to the National Register of Historic Places.

This video is a comprehensive look at the history of the Hiram M. Chittenden (Ballard) Locks and their impact to the Seattle area. Learn how early Seattleites envisioned a waterway between Lake Washington and the Puget Sound and how the U.S. Army Corps of Engineers made it a reality.. 

The Hiram M. Chittenden Locks were designed and built for the nation with commerce in mind. For years logs and coal traversed the now 100-year-old locks. Today, a large portion of the Alaskan Fishing Fleet moors in Seattle's fresh waters and use the Locks, but it's the smaller recreational boats that make us the busiest Lock in the nation in terms of vessel traffic. Nearly 50,000 boats lock through each year. This video tells the story of how the Locks in Ballard make Seattle a hot spot for recreational boating. 

Who was Hiram Chittenden and what does the Army have to do with the locks? In this video you can learn about the history of the Locks and the U.S. Army Corps of Engineers’ role building them. Also, you will learn about Chittenden and meet his great-grandchildren. 

If you've ever come to the Chittenden Locks in Ballard, you've probably visited our fish ladder, and you may have seen salmon in our viewing windows. Did you know salmon have been coming through our fish ladder for a hundred years now?

This video tells the story of how Native American Tribes in the Seattle area were affected by the building of the Chittenden Locks and the Lake Washington Ship Canal in 1917.

Nearly 50,000 vessels lock through the Hiram M. Chittenden Locks in Ballard, with many of the Alaskan fishing fleet docking at Fishermen’s Terminal.  This episode is about the terminal and the fleet's boats that come through the locks all year long. 

At the Chittenden Locks, locally known as the Ballard Locks, we see many boats and ships coming through every day.  Many are visiting one of the shipyards along the Lake Washington Ship Canal, where they get re-fitted and repaired. As part of our centennial, we teamed up with a local film teacher and his students to tell stories about our history and impact on Seattle.