SR 9 - Marsh Road to 2nd Street Vic - Widening

Project news

  • Design work is underway.
  • Construction is scheduled to begin in 2022 with completion in 2025.
  • Sign up for email updates about state highway projects in Snohomish County.

Needs & benefits

Improvements to SR 9 in Snohomish County are necessary because the county continues to grow significantly as a home for both people and businesses. Besides I-5, SR 9 is the only other north-south route that travels through the entire county. As a result, SR 9 highway users are experiencing more congestion.

WSDOT will add two more lanes from Marsh Road/Airport Road to the 2nd Street on- and off-ramps in Snohomish. The improvements include building bridges immediately to the west of the existing bridges over the Snohomish River and the flood channel. These new lanes will carry southbound traffic. The existing lanes will be converted to northbound use only.

Widening the highway will benefit highway users with reduced backups, better travel times, and improved access to Snohomish and northern Snohomish County.  


  • 2019: Restart design
  • 2022: Begin construction
  • 2025: Open new lanes and ramps


This project received $142 million from the 2015 Connecting Washington transportation package.


Jennifer Rash, communications

A small map showing the location of improvements on SR 9 between Marsh Road and 2nd Street in Snohomish, Washington.

Looking north on SR 9 at the intersection with Marsh Road, which is the southern end of the project to widen the highway to 2nd Street in Snohomish, Washington.

The intersection of SR 9 and Marsh Road, looking north on SR 9.