Knapps Hill Tunnel on Highway 97A is expected to reopen by at least Friday after being closed since June 14 because of rock slide danger.
Work on the hillside stabilization should be finished by Thursday and the tunnel should be reopened sometime that night, but certainly by Friday morning, said Lauren Loebsack of Washington State Department of Transportation.
The project was one of three along 97A to deal with a growing problem of large boulders sliding into the highway.
Work on the other areas was completed June 25.
Though work on all three sites had been planned for months, the Knapps Hill Tunnel was closed early on an emergency basis after repeated slides.