Corps begins spillway gate rehabilitation work at Detroit Dam

The U.S. Army Corps of Engineers will perform spillway gate rehabilitation work at Detroit Dam from Friday, Nov. 1 through Feb. 15, 2020.

During this period of time, the road running across Detroit Dam will be closed to vehicles and pedestrians.

Contractors will use the parking lot at the top of the dam as a staging area during construction. This parking area is currently fenced off from the public and the restroom is closed.

In 2010, the Corps discovered potential issues with spillway gates at Detroit Dam and implemented an interim risk reduction measure to limit operating the gates at high reservoir levels. This only affected operations at water levels above maximum conservation or “summer pool” elevations during very large or late season flood events.  

In 2011, the Corps completed a comprehensive spillway gate study and determined the 66-year-old spillway gates at Detroit Dam were in need of rehabilitation to restore functionality and provide the authorized flood risk reduction capabilities to the reservoir.

"This gate rehabilitation project is part of the larger dam safety program that has completed spillway gate repairs at 6 of the 13 Willamette Valley dams," said Lauren Bennett, Corps spokesperson. "The Corps has worked diligently to complete repairs in order of priority ranking to minimize risks as quickly as possible."

The Corps will work on two gates per year over the next three years to complete work on all six spillway gates to restore full structural capabilities and improved reliability. The anticipated project completion date is February 2022.

This work is scheduled during a time when the reservoir is at its lowest level, so there is no need to draw down the reservoir. The Corps does not anticipate impacts to routine water operations.

For more information, visit https://www.nwp.usace.army.mil/Missions/Water-Management/Spillway-Gates/ or call 503-808-4510.

Willamette Valley Project: The U.S. Army Corps of Engineers operates 13 dam and reservoir projects in the Willamette River drainage system. Each dam contributes to a water resource management system that provides flood damage reduction, power generation, irrigation, water quality improvement, fish and wildlife habitat and recreation on the Willamette River and many of its tributaries. Since their completion, the dams have cumulatively prevented over $25 billion in flood damages to the Willamette Valley. For more information, visit http://www.nwp.usace.army.mil/.