Chittenden Locks to close June 5 for salmon exclusion structure inspection

Published June 1, 2012

SEATTLE – The Hiram M. Chittenden Locks in Ballard will close to all marine traffic 7:30 a.m. until 1 p.m., June 5 allowing U.S. Navy divers to inspect the Adult Salmon Exclusion Structure.

The structure, immediately upstream of the locks, prevents salmon from entering the locks’ saltwater return intake. Prior to the 2008 installation, adult salmon sometimes entered a diffuser well beneath the fish ladder. The well does not have an exit and entering it led to salmon migration delay, injury or death.

Navy divers from Naval Base Kitsap, will close 10, 10-foot-by-6-foot doors and inspect the 30-by-60 foot curved-front, mesh screen structure. The Navy annually supports the Corps with this procedure before salmon migration season begins in mid-June. The doors will be opened again in mid-September.

Salmon have always been vital to the Pacific Northwest’s ecosystem. The U.S. Army Corps of Engineers, Seattle District Engineer Maj. Hiram M. Chittenden, for whom the locks are now named, understood this and incorporated a fish ladder in the designs when he proposed building them in the early 1900s. The exclusion structure improves viability of the salmon that use the fish ladder to return upstream to their spawning grounds.

The operation requires the Locks be closed to all but emergency vessels on emergency calls. The staff will make maximum efforts to complete the work as soon and as safely as possible. Boaters may call the lockmaster on duty at 206-783-7000 to verify the locks are open.

Public Affairs Office

Release no. 12-008