SR 401 slide cleared, highway now open
November 18, 2021
Washington State Department of Transportation announced Tuesday evening that the slope adjacent to SR 401, also known as Lewis and Clark Trail Highway, between the Astoria-Megler Bridge at and Knappton Road has been stabilized, and the roadway is now open.
On Oct. 27, WSDOT maintenance crews closed the 9-mile stretch after heavy rainfall triggered a debris slide on to the roadway.
After WSDOT geotechnical engineers assessed the stability of the slope above the roadway, they determined additional debris could fall and needed to be removed. WSDOT hired an emergency contractor who began working to complete the removal of loose debris and stabilize the slope on Nov. 15.
This slide was in the same vicinity of the highway closure last February, and the full stretch of SR 401 closed for several weeks. On April 15, contractor crews opened a temporary single lane bypass road, restoring travel through the area.
Construction work to stabilize the adjacent slope and perform long-term repairs to the highway near milepost 4.5 are scheduled to begin in spring 2022.