The Hiram M. Chittenden Locks (aka Ballard Locks) is situated at the west end of Salmon Bay and the Lake Washington Ship Canal, separating the fresh waters of Lake Union and Lake Washington to the east from the tidal waters of Puget Sound to the west. At the same time, the locks maintain the water level of Lake Union and Lake Washington approximately 20 feet above sea level and use a system of gates and sluices to raise and lower commercial and recreational vessels between the two water levels.

The complex consists of a small lock and a larger one that is 80 feet wide. Construction was completed in 1917 by the U.S. Army Corps of Engineers and the Locks are now listed on the National Register of Historic Places and the American Society of Civil Engineers Historic Civil Engineering Landmarks.