LEWISTON, ID — Motorists traveling on U.S. Highway 95 between Lewiston and Moscow should prepare for extended delays this week as crews complete concrete work on the Thorn Creek Bridge.
Beginning Wednesday, the Idaho Transportation Department (ITD) will reduce traffic to a strict 5 mph across the bridge while crews pour high-strength concrete. The speed restriction is necessary to prevent vibrations from affecting the curing process. Delays of approximately 20 minutes are expected, with longer backups possible during peak commuting hours. The concrete work is scheduled for Wednesday, with curing to continue Thursday and Friday. Restrictions will remain in place even when active work is not occurring.
Drivers are encouraged to plan ahead and consider alternate routes, including State Highway 8 and the Moscow-Pullman Highway in Washington, to avoid congestion.
The Thorn Creek Bridge project is among the final steps in completing the new four-lane highway realignment between Reisenauer Hill and Moscow. Construction began in 2022 to shift the curving two-lane section eastward and expand it to four lanes, improving safety with a flatter grade, fewer curves, and better access control. The nearly $90 million project is partially funded through Governor Brad Little’s Leading Idaho program.
Five miles of the new alignment opened to traffic in July, and the last mile is expected to be finished by November. Updates on this project and other statewide roadwork can be found on the Idaho 511 app or at 511.idaho.gov .