Major repairs to the State Route 107 bridge over the Chehalis River South of Montesano will mean either a complete closure and 7-month detour through Aberdeen, or 10 months of truck detours and local-only traffic next summer.

Project Engineer John Romero with the Washington State Department of Transportation said during an open house this week. “This is being built no matter what, how do we manage traffic? Alternate 1 is to keep local traffic moving across the bridge, but it would be alternating one-way traffic. The bigger trucks coming up, they would have to use [US Route] 101 and go around through Aberdeen.”

Romero explained alternate option 2, “close it completely down for everybody, and the construction would take a total of 7 months.”


Improvements to the 58-year-old bridge include replacing the timber south approach span and bridge rail with a concrete span, adding steel safety railing, as well as painting the steel surfaces.

SR107 Chehalis River Bridge Monte
The South side of the bridge approach will look like the North side when the project is completed.

The work is expected to run from Summer 2017 into Late winter 2018.┬áIf you’d like to provide input, visit and click on projects.

Project Benefits

  • Reduce maintenance frequency and costs by replacing the deteriorated timber approach trestle with a concrete structure.
  • Reduces severity of collisions by installing modern traffic barriers and guardrail.
  • Preserves the steel trestle by painting.

What is the project timeline?

  • Fall 2016: Finalize structure rehabilitation plan.
  • Summer 2017 through 2018: Construction