STC-5770, merritt bridge repairs, bonner county

The Idaho Department of Transportation received a $1.02 million formula grant from the Federal Highway Administration (FHWA) under the Highway Planning and Construction program (CFDA 20.205), awarded on June 5, 2025, for the rehabilitation and repair of the Merritt Bridge in Bonner County, Idaho. The project, designated STC-5770, will extend through July 31, 2032, and addresses critical substructure deterioration on the 1956-constructed bridge, which received a superstructure upgrade in 1988. Predictive models indicate the substructure will reach poor condition by 2025 without intervention.

The project scope includes cleaning and pile wrap repairs to the bridge substructure to prevent imminent deterioration and avoid full bridge replacement costs in the near term. Additionally, the funding supports application of an epoxy coating to the concrete deck driving surface to protect and extend the life of the concrete and rebar within the superstructure. These preventive maintenance and rehabilitation activities represent strategic infrastructure preservation under FHWA's federal-aid highway program, which supports highway and bridge construction, preservation, and improvement projects administered through state transportation departments.

Project description

For the work to rehabilitate and repair the bridge which was constructed in 1956 and then upgraded in 1988 with a new superstructure. The bridge's substructure is in need of its next rehabilitation to extend its life. Based on predictive models, the substructure is anticipated to drop to poor condition by 2025. Investing in a cleaning and pile wrap repair now will extend the substructure's life and avoid a total bridge replacement being necessary in the nearer future. The concrete deck of the bridge would also benefit from an epoxy coating on the driving surface at this time to protect and extend the life of the concrete and rebar of the superstructure and is proposed as part of this project.