Overview
ITD will begin reconstructing a 7-mile section of State Highway 3 between Fernwood and Clarkia in spring of 2026 using a recycled asphalt process to improve durability and reduce costs. In 2027, the nearby St. Maries River Bridge will be fully replaced with a modern structure, maintaining one-lane traffic throughout construction. The combined projects aim to enhance safety and mobility, with an estimated total cost of $5 million.
Pavement rehabilitation starts in spring 2026
Set to begin in spring of 2026, ITD will begin a roughly $9 million pavement rehabilitation project on a 7-mile section of State Highway 3 between Fernwood and Clarkia using a comprehensive restructuring process known as Cement Recycled Asphalt Based Stabilization, or CRABS.
This process allows crews to pulverize the existing asphalt and mill down through the base layer of the roadway. They then mix in cement to help stabilize and strengthen the material to use as a base beneath a newly paved driving surface. CRABS projects save time by eliminating the need for loading and hauling away the old asphalt and saves money by recycling old material into the new base and eliminating waste.
During construction crews will work on a single lane at a time, reducing traffic flow to one alternating lane through the use of flagging and pilot cars. For the duration of construction drivers should expect to plan for an additional 10 to 15 of commute time to accommodate delays for alternating traffic. This project is expected to be complete by the end of 2026.
Updates for traffic impacts will be available to drivers by utilizing the Idaho 511 system.
St. Maries River Bridge replacement in 2027
Scheduled for construction in 2027, ITD is planning to fully replace the St. Maries River Bridge that was originally constructed in the 1930s. Since that time, the bridge received minor deck improvements in the 1950s and held strong until fall of 2020 when structural deficiencies were identified in the center piers resulting from deterioration caused by seasonal fluctuations in water levels.
At that time, crews engineered and installed temporary bracing that allowed the bridge to function at full capacity until late 2023 when additional deficiencies were discovered through the bridge’s annual inspection.
In response to the inspection findings, ITD implemented temporary lane and weight restrictions in late 2023 to allow for the safe continued use of the bridge until additional temporary repairs could be made. These repairs were completed in 2024 and returned the bridge to full, unrestricted service until its replacement.
A full replacement of this bridge in 2027 will include the demolition of the existing structure and constructing new abutments, piers and decking built to modern standards.
This project is being designed to maintain one lane of traffic throughout construction to eliminate the need for detours and allow better mobility for the local community. Work is expected to be completed within one year.
The total cost for construction of this project is estimated to be approximately $5 million.
Timeline
This project is currently in design and is scheduled for construction starting in 2026.
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2025
Project is in design phase
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2026
CRABS pavement rehabilitation project begins
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Late 2026
CRABS pavement preservation project complete
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2027
Replacement of the St. Maries River Bridge
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Late 2027
Expected completion
Contact the project team
For questions or comments about this project, please contact the project manager at jacob.edlund@itd.idaho.gov or (208) 772-1200.