Claudia Bingham Baker, WSDOT communications, 360-357-2789
UNION – Motorists traveling along scenic State Route 106 should expect delays up to 15 minutes from early September to mid-October while crews remove and replace a culvert under the highway.
Starting Tuesday, Sept. 3, crews working for the Washington State Department of Transportation will reduce SR 106 to one-way, alternating traffic around the clock near Twanoh State Park, eight miles east of Union. That one lane of traffic will be rerouted onto a temporary, 600-foot-long detour built adjacent to the highway.
The speed limit through the work area has already been reduced to 25 miles per hour. The work area includes the SR 106/Creekside Drive intersection, which provides access to approximately 400 homes. Flaggers will provide around-the-clock traffic control to maintain access to those homes during the seven weeks the detour is in effect.
In those seven weeks, crews will cut through the roadway asphalt to expose and remove the existing three-foot-wide culvert, and replace it with a 20-foot-wide culvert. The new culvert’s substantially increased capacity is expected to reduce the potential for localized roadway flooding, which has been a chronic problem. A side benefit is that the larger culvert will provide an enhanced passageway for fish.
After the new culvert is installed, crews will repave the highway, which will be about six feet higher at the site to accommodate the larger culvert, and restore the previous 40 mile-per-hour speed limit. The project is scheduled to be complete this fall.