Project overview
This section of SR 531 between 43rd Avenue Northeast and 59th Avenue Northeast in Arlington will be widened to add a second lane in each direction. In addition, roundabouts will be added at the 51st Avenue Northeast and 59th Avenue Northeast intersections to improve safety, travel times and reduce congestion.
What to expect
Beginning in late 2026 or 2027, SR 531 will be expanded to four lanes with intersection improvements between 43rd Avenue Northeast and 59th Avenue Northeast. Bicycle/pedestrian shared-use paths will be constructed on the north side of the roadway.
Intersection improvements will be made at 51st Avenue Northeast and 59th Avenue Northeast.
Work is expected to include updating illumination, drainage and stormwater, with environmental impacts being mitigated. Additional improvements include the replacement of the airport’s advance lighting.
Work on SR 531 between 43rd Avenue Northeast and 59th Avenue Northeast in Arlington will add a second lane in each direction and build two roundabouts at 51st and 59th avenues northeast.
Design strategies and elements
This project will increase safety by reducing congestion and providing safe multimodal access on a two-lane roadway system that does not meet the demands brought by recent development along the corridor. Improving the efficiency of the corridor through expansion will address concerns with vehicle residency time within the airport’s runway protection zone.
This project will reduce collisions within the corridor, provide congestion relief, provide a multi-modal path east/west route in the city, and accommodate the increase in freight throughout this corridor. The project is proposed to be delivered in phases in response to project risks, funding challenges and to maintain construction schedule commitments.
Background
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 2019, 26,000 vehicles used this stretch of highway daily, compared with 18,000 vehicles in 1999.
When construction begins, we will improve and widen the two-mile stretch of highway between 43rd Avenue Northeast and 59th Avenue Northeast and build roundabouts to manage congestion and improve safety. The roundabouts will provide safer access to the highway from businesses and improved access for people who walk, ride bicycles, use the bus or need ADA accommodations.
Roundabouts
Studies have shown that roundabouts are safer than traditional stop signs or signalized intersections and reduce injury crashes. They move traffic more quickly and are less expensive to maintain. Learn more about the benefits of roundabouts.
