Work to begin on the Hiram M. Chittenden Locks scour repair project

Seattle District
Published Sept. 12, 2020

Seattle District, U.S. Army Corps of Engineers’ officials have announced work will begin on the Emergency Scour Repair Project September 15.

The scour repair work is slated to run through October 15th. During the project, residents in the area of the Locks may hear construction noise during the evening hours. Measures will be used to reduce noise, such as temporary barriers around stationary noise generating equipment and restricting use of certain types of noisy equipment. Working in the evening avoids most adult salmon migrating upstream.

The Emergency Scour Repair Project will correct concrete erosion near the Locks’ fish ladder, which was first observed in a 2019 survey. The damage worsened in February 2020, after a historic inflow event, caused by back-to-back winter rainfall events that resulted in free-flow spilling at the Locks.

Lake residents and users will notice a faster lake level drawdown than typical years to prepare for the repair project, which will occur near the Locks’ spill gates. Corps officials are recommending floating homeowners, others with floating structures and vessels moored on lakes Washington and Union and along the Ship Canal to prepare for a faster rate of lowering water levels.

Dallas Edwards

Release no. 20-116