The Washington Dept. of Transportation recently conducted a briefing on what is called the 405/Brickyard to SR 527 project. The project is just getting underway and involves expansion of Interstate-405 from just south of the complex SR 522 interchange north through the SR 527 – Canyon Park interchange.

The expansion of the freeway includes widening the roadway including the Express Toll Lanes, two new bus rapid transit stations, adding direct access ramps at SR 522 and SR 527, and correcting fish barriers along this stretch of the freeway.

The most significant visible road construction will involve complete remodeling and access points for cars, buses and pedestrians at both the SR 522 and SR 527 interchanges. New bus rapid transit stations will be built in the median of the freeway similar to the one in Totem Lake and will involve new access bridges over the freeway to the new transit stations.

Preliminary roadwork is already underway, but the first significant changes for motorists will involve lane shifts and slower speed limits along SR 522 through the 405 interchange area.

During two mid-April weekends, SR 522 will have lane closures as a lane shift project is constructed. The speed limit will drop to 35 mph, similar to and an extension of the speed limit out of downtown Bothell. Watch for these changes in the near future. Northshore School District is already planning for these changes since it will impact current school route timing.

The overall project is planned to be completed by the fall of 2028. In the meantime, motorists should expect significant construction, potential overnight lane restrictions, narrowing of lanes, and lower speed limits. Remember; slow down through any roadwork sites to avoid collisions and mishaps with workers.

Regarding the Express Toll Lanes, the new infrastructure is expected to be in place by the fall of 2027 and activated in March of 2028.

Funding for this project originates from a suite of local and state resources. They include:

  •      Motor Vehicle Account (vehicle license and registration – local)
  •      Toll revenue (revenue from managed system of express toll lanes that is reinvested back into the corridor)
  •      Gas tax from two Washington Legislature bills – the 2015 Connecting Washington and 2005 Transportation Partnership
  •      Move Ahead Washington – a collection of funding sources including deferred construction related sales tax
  •      Partnership with Sound Transit (20% of project funding from Sound Transit to support infrastructure components associated with Bus Rapid Transit)

Updates on this project are available from a variety of sources. They include:

You can also email [email protected] for additional information and questions.