I-5 - Chamber Way - Stage 2

Project news

Interstate 5 or I-5, serves as the primary connecting highway on the west coast, running parallel to the Pacific Coast through California, Oregon, and Washington, and is the only highway in the nation to touch both the Canadian and Mexico borders.

To keep people and goods moving through Washington State, this project will focus on reducing congestion and improving safety on the I-5 corridor between the Chamber Way interchange and the State Route 6 interchange, in Lewis County. 

Subject to cost savings provided by practical design solutions within the project budget, this project will also seek to reduce congestion and improve safety on Interstate 5 between the Chamber Way and the Mellen Street interchanges.

Needs & benefits

Why is WSDOT looking to reduce congestion and improve safety and mobility at the I-5 Chamber Way interchange?
Due to an increase in congestion during weekday peak commute times (typically between 4-6 p.m., on weekdays and between 12-2 p.m., on Fridays) and in an effort to improve safety and trip reliability, the Washington State Department of Transportation is looking at ways to improve mobility near I-5 and Chamber Way, in Chehalis. Once completed, travelers should experience less congestion, reduced travel times and an increase in travel time reliability. 

This project is still in the early design phase.  Next steps include developing solutions and alternative assessment which we expect will result in identifying Interstate System improvements.

Study Area

The I-5 Chamber Way - Stage 2 project spans multiple local jurisdictions in Lewis County between the cities of Chehalis and Centralia.​

The general study limits may include the following:

  • I-5 between SR 6/Main Street and Mellen Street
  • Chamber Way between Louisiana Avenue and National Avenue
  • West Street between Louisiana Avenue and State Avenue
  • SR 6/Main Street between Riverside Drive and State Avenue

End Results

  • Safety:  This project will look at ways to improve safety throughout this corridor.
    • Between 13th Street (Parkland Drive) and Harrison Avenue, collisions have increased by nearly 40 percent during peak commute times, between 2014 and 2018.
    • There were a total of 1,146 crashes in the study area, two-thirds of the collisions in the study area were rear-end and side-impact crashes, which are generally associated with congested traffic conditions.  
  • Mobility: This project will look at improvements to address the mobility along the corridor, including freight, general highway traffic, local traffic and transit.


  • 2020 - 2021: Conduct community outreach efforts through public online houses, mailers and flyers 
  • Early 2023: Project goes to competitive bidding
  • Spring 2023: Construction scheduled to begin
  • Late 2024: Construction scheduled for completion


The estimated cost of this project is $60.75 mil. This is a Connecting Washington funding package. 


Colin Newell - Project Engineer

Celeste Dimichina - WSDOT Communications

I-5 - Chamber Way - Phase 2 - project location near Chehalis in Lewis County