• Project

I-405/Brickyard to SR 527 Improvement Project

Project overview

The I-405/Brickyard to SR 527 Improvement Project enhances four and a half miles of the corridor, primarily in Bothell, from just south of the State Route 522 interchange and ending at the SR 527 interchange. WSDOT, Sound Transit and design-build contractor Skanska USA Inc., will deliver improvements that benefit all users, while addressing aging infrastructure, opening upstream fish habitat, and connecting communities, freight and Regional Growth Centers throughout the corridor.

Since implemented in 2015, express toll lanes (ETL) have helped improve reliability of trips on the north end of the I-405 corridor, however the single-lane section still experiences heavy congestion, especially for people traveling south during the morning commute. The project will extend the dual-express toll lane system on the north end of I-405 and improve access to the voter-approved Stride bus rapid transit service to address congestion and help keep all vehicles moving efficiently.

This project includes three new Stride stations and will build direct access ramps to the ETL system at SR 522, along with a partial direct access interchange at SR 527 to and from the south connecting to the Canyon Park Park & Ride. These enhancements will allow Stride vehicles to travel in the new ETLs between Lynnwood and Bellevue while stopping briefly to pick-up and drop-off passengers without having to leave the highway system. Having dedicated ETL access in the center of the freeway will make travel more efficient supporting the new Stride service with buses arriving every 10 minutes for most of the day.

Additionally, the project will address aging infrastructure, restore stream connections, add noise walls and add new stormwater facilities.

Timeline
The project is expected to complete construction in 2028 in alignment with Sound Transit Bus Rapid Transit.
Project status
Construction
Funding
$834 Million

What to expect

Overnight work requiring lane and ramp closures throughout the 4.5 mile construction zone with some exceptions for extended closure hours. Work includes traffic shifts to create new work zones, where crews will build new inline bus rapid transit stations and work to remove fish barriers. Check the travel map for alerts.

Map of I-405 showing the area that will be improved, from SR 522 to SR 527, highlighted in orange.

Overview

The 50-mile I-405/SR 167 corridor serves a rapidly growing region from Lynnwood to Puyallup. As the area exceeds projected population growth, attracts large businesses, and creates more jobs, the demand for transportation systems continues to increase. To meet this growing demand, we continue a 20-year history of working with cities, counties, the Legislature, and transit agencies along the corridor to carry out the long-term vision for transportation along this important north-south corridor. 

A major part of the I-405/SR 167 multimodal vision includes building a corridor-wide express toll lane (ETL) system from Puyallup to Lynnwood and supporting a high-capacity transit system called Bus Rapid Transit (BRT). Improvements to our I-405/SR 167 corridor and implementing Sound Transit’s I-405 Stride system are essential to the region’s transportation network, readiness for growth, and quality of life.

I-405 Express Toll Lanes (ETLs)

In 2015, we launched ETLs between Bellevue and Lynnwood with two ETLs in each direction between Northeast Sixth Street in Bellevue and just south of the SR 522 interchange in Bothell and a single ETL between SR 522 and I-5. While express toll lanes have helped reduce traffic and improve reliability on the north end of the I-405 corridor, the single-lane section still experiences heavy congestion, especially for people traveling south during the morning commute.

The Brickyard to SR 527 Improvement Project aims to relieve some of that pressure by adding an additional express toll lane in each direction in this area. Consistent with the long-term vision for the corridor, we are moving forward with these additional improvements to mobility and reliability on I-405 in Bothell and south Snohomish County.

Sound Transit Stride bus rapid transit

We have worked closely with the City of Bothell and Sound Transit to design the new inline Stride station at the Brickyard Park and Ride in Bothell. Stations and direct access ramps to the ETLs also will be added to the SR 522 and SR 527 interchanges. These Stride stations will integrate with the voter-approved Stride service along I-405. This work will enable Stride vehicles to travel exclusively in the new ETLs between Lynnwood and Bellevue, increasing service reliability, and decreasing Stride travel times. This new system will offer better transportation options for everyone who uses I-405.

Economic contributions

The project will contribute to economic growth in the region by investing in key Bothell destinations and employment centers, including the University of Washington (UW) Bothell/Cascadia College campus, two business parks, a commercial center with a variety of businesses, and residential development. It also supports the City of Bothell's efforts to update the Canyon Park subarea plan, which notes the importance of WSDOT and Sound Transit transportation investments in this area.