WSDOT moves forward with fast-tracked improvements to north end of I-405

Much-needed relief is coming soon for northbound Interstate 405 travelers experiencing traffic headaches during their afternoon trips through Bothell and south Snohomish County.

The Washington State Department of Transportation selected a design-build contractor for the new I-405 Northbound Peak-Use Shoulder Lane Project on Nov. 9. Graham Contracting Ltd. of Bellevue submitted the apparent best value proposal of $7.29 million.

Expected to open to traffic by spring 2017, the new 1.8-mile peak-use shoulder lane on northbound I-405 will operate between State Route 527 in Bothell and Interstate 5 in Lynnwood.

As the name suggests, a peak-use shoulder lane allows all drivers to use the right shoulder as an additional general-purpose lane during times with the heaviest congestion—in this case, the weekday afternoon commute. Overhead lane control signs will alert drivers to when the lane is available for use.

In general, express toll lanes have provided a faster, more reliable trip option for I-405 travelers since opening between Bellevue and Lynnwood more than a year ago. However, northbound I-405 has been experiencing additional congestion between State Route 522 and I-5, where the number of lanes reduces from five to three. Adding to that bottleneck is the busy SR 527 interchange, where nearly 1,000 cars an hour merge into the congested northbound I-405 lanes during the afternoon peak period.

“We’re continuing to see population growth in our region, and this section of I-405 struggles to handle all of the increasing demand,” said I-405/SR 167 project director Kim Henry. “Our long-term plan calls for additional improvements in this area. In the short-term, we’re pleased that we can accelerate this project and help bring some relief to north end commuters sooner than originally scheduled.”

The peak-use shoulder lane project is the first construction project to be funded by I-405 express toll lanes revenue. The Legislature originally funded the project with an expected opening date in 2018. With toll revenues, WSDOT is now able to begin construction at least six months earlier. The Legislature also asked WSDOT to identify and prioritize other future projects that will add capacity to the section of I-405 between SR 522 and I-5, as envisioned by the master plan.

Next steps for construction

Early next month, WSDOT and Graham expect to sign a contract giving notice to proceed on design and construction activities. As part of the project, contractor crews will restripe the roadway, add new pavement in certain areas and install overhead lane control signs. Crews will also build a new noise wall designed to reduce highway noise for nearby neighbors.

I-405 travelers can expect to see construction activities start up this winter. The latest road closure information will be posted on WSDOT’s construction update website throughout the project.