SR 531 - 43rd Ave NE to 67th Ave NE - Widening

Project news

  • WSDOT teams are currently working on preliminary design plans and environmental reviews.
  • This project is scheduled for construction in 2023 and 2024.

Needs & Benefits

State Route 531/172nd Street Northeast runs through the city of Arlington and into Snohomish County near the Arlington Municipal Airport.  Development of residential areas east of this busy freight corridor continues to increase annual traffic volumes. In 1999, 18,000 vehicles used this stretch daily, compared to 26,000 vehicles in 2019 and an average of three serious crashes happen in this area each year.

This two year corridor improvement project is scheduled to start construction in 2023. WSDOT will improve the two-mile stretch of highway between 43rd Avenue Northeast and 67th Avenue Northeast. The project will include congestion and safety improvements at four intersections, safer access to the highway from businesses and improved access for people who walk, ride bicycles, use the bus or need Americans with Disability Act accommodations.

Project challenges
Challenges associated with this project include but are not limited to:

  • Purchasing nearly two dozen needed pieces of right-of-way property before construction.
  • Relocating numerous utility lines and pipes that run along SR 531.
  • Working with the Federal Aviation Administration to create a design that accommodates aviation needs.
  • Working with BNSF Railroad to make intersection improvements near its tracks at 67th Avenue Northeast.
  • Making required environmental (storm water, culvert and catch basin) improvements and completing appropriate wetland mitigation.
  • Improving an existing culvert that is currently a barrier to fish passage.
  • Keeping costs within the non-flexible Connecting Washington funding allocation.
  • Keeping businesses accessible and traffic and aviation moving through this corridor during construction.

What to expect
WSDOT will conduct a variety of outreach activities to keep the community updated during key stages of the remaining design process.

Once construction begins, WSDOT will update travelers through weekly emails, on our construction update website and will show photos and videos of the working being done on our project Flickr page.


July 2019: Began design engineering.
Fall 2020: Complete environmental review documentation.
Fall/winter 2022/2023: Finalize design and traffic control plans and award project to a contractor. 
Spring 2023: Begin first year of construction.
Fall 2024: Complete construction. 


The current estimated total project cost is $39.3 million. Funding will primarily come from the Connecting Washington transportation package


Kris Olsen

Shane Spahr
Project Engineer

A small map of a SR 531 project area between 43rd Ave. NE and 67th Ave. NE.

A small map of a SR 531 project area between 43rd Avenue Northeast and 67th Avenue Northeast.

A small photo of SR 531 looking west. Photo includes a dirt pedestrian trail and a sign showing 43rd Ave. NE is ahead.

A small photo of SR 531 and a dirt pedestrian path looking west toward 43rd Avenue Northeast.