Bridge on ID-3 in St. Maries closes next week, requiring detour through town

The Idaho Transportation Department advises drivers to plan ahead for traffic delays and detours in St. Maries on Idaho Highway 3 as crews advance to the next phase of bridge reconstruction.

Beginning as early as Tuesday, Sept. 4, crews will close the bridge over the railroad and reopen the adjacent bridge over the St. Joe River to one lane in each direction.

Temporary signs will be installed along the detour through town to enhance safety and traffic flow. Closures will continue on Meadowhurst Drive east of its intersection with ID-3 as well as Riverside Avenue where it runs underneath the highway between First Street and Fourth Street.

These traffic changes are part of the ongoing project to upgrade two bridges in St. Maries. This phase of work includes completing the east half of the river bridge deck and reconstructing the railroad bridge.

The railroad bridge is anticipated to be closed through December, and the overall project is scheduled to be complete by spring 2019.

Upon completion, both bridges will include one lane in each direction with a shoulder and sidewalk on each side. Work also includes reconstructing the highway to match the upgraded bridges, replacing guardrail and signs in several locations and improving the adjoining intersections.

Crews are working during daylight hours Monday through Saturday and Sundays as needed. Residents and businesses will continue to experience occasional noise, dust and vibration during that time.

Check 511 for traffic impacts or visit the “Projects” tab at for more information.

Members of the public are also invited to contact the project team by calling the project hotline at 208-292-8515 or by emailing Gemma Puddy at