Four-day closure of SR 20 at Olson Creek begins Sept. 9 in Marblemount to modify fish passage

MARBLEMOUNT – People traveling along State Route 20 in Marblemount the week of Monday, Sept. 9, will encounter a detour while crews perform work as part of the Olson Creek fish passage project.

Contractor crews working on behalf of the Washington State Department of Transportation will close eastbound and westbound SR 20 from 6 a.m. Monday, Sept. 9, until 6 a.m. Friday, Sept. 13. During the closure, they will remove the existing culvert, construct a new bridge and build retaining walls.

People traveling in the area should allow extra time to get around the closure through a signed detour.

Additionally, crews will improve the roadway by paving, striping, and installing guardrail and other roadway safety items. Travelers should also expect occasional single-lane closures along SR 20 as needed through the duration of the project, which is scheduled to finish this fall.

The new fish-passage structure will open approximately 1.5 miles of habitat, making it easier for native species of fish such as trout and salmon to navigate the creek.

People can find real-time updates for the full road closure by checking the WSDOT Travel Map and X/formerly Twitter.

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