Sound Transit board OKs funding for Interstate 5 bus-on-shoulder program between Lynnwood, Mountlake Terrace

The Sound Transit Board Capital Committee Thursday approved funding for investments to speed up buses by operating them on the shoulder of a segment of southbound I-5 between Lynnwood and Mountlake Terrace.

The project, between the Lynnwood Park and Ride and the Mountlake Terrace Freeway Station, is the first to move forward under a new bus-on-shoulder program funded by voter approval of the Sound Transit 3 ballot measure, a Sound Transit announcement said. Community Transit, whose riders will also benefit from the project, worked with WSDOT and Sound Transit to identify the project.

Under the bus-on-shoulder program, Sound Transit and the Washington State Department of Transportation will work together to identify other locations where it is feasible to improve transit speed and reliability during peak times by allowing buses to use highway shoulders in locations where traffic congestion causes frequent delays.

The Capital Committee’s action enables WSDOT to advertise the southbound I-5 construction project to bidders and Sound Transit and WSDOT to begin assessing other areas where bus on shoulder operations could work on I-5, I-405, SR 167 and SR 518.

“We are very happy that this significant investment in Snohomish County is closer to being implemented and closer to easing some of the pressure on our roadways,” said Dave Somers, Snohomish County Executive and Sound Transit Board Chair. “Our close partnership with WSDOT allows Sound Transit to get started quickly on this early deliverable ST3 project. Working together and with public support, our agencies will continue to identify every opportunity to speed commuters across the congested Puget Sound region.”

“The bus-on-shoulder program is a great example of working together with our transit partners to provide Washingtonians with safe and convenient transportation choices,” said WSDOT Secretary Roger Millar. “Allowing buses to run on the highway shoulder is a practical way to improve speed and reliability, allowing commuters to spend less time on the road and more time doing other things.”

“Traffic congestion continues to get worse, and bus commuters often find themselves experiencing the same delays as drivers in their personal vehicles,” said Sound Transit Chief Executive Officer Peter Rogoff. “While we continue work to bring light rail to Lynnwood and Federal Way in 2024, the bus on shoulder program will help improve the commute time for those who ride the bus into downtown from Snohomish County and other parts of our region.”

The bus-on-shoulder program is among numerous voter-approved investments Sound Transit is working to advance as the region’s population and congestion continue growing rapidly.

Sound Transit is simultaneously working to extend light rail north, south, east and west, opening new stations every few years to form a 116-mile regional system by 2041. The agency is on track to open extensions to Seattle’s University District, Roosevelt and Northgate neighborhoods in 2021, with service to Mercer Island, Bellevue and Redmond’s Overlake area opening in 2023. Additional extensions to Kent/Des Moines, Federal Way, Shoreline, Mountlake Terrace, Lynnwood and Downtown Redmond will open in 2024.


Thereafter light rail extensions are scheduled to reach Tacoma and West Seattle in 2030; Ballard in 2035; Paine Field and Everett in 2036; and South Kirkland and Issaquah in 2041. The Tacoma Link light rail system will reach the city’s Hilltop neighborhood in 2022 and Tacoma Community College in 2039.


Other upcoming transit expansions include the 2024 launch of bus rapid transit on I-405 and SR-522, major expansions to Sounder south line service that include longer platforms and trains, and service extensions to Joint Base Lewis-McChord and DuPont.


Information on upcoming Sound Transit system expansions is available at



  1. As s regular community transit bus rider from Ash Way Oark & Ride to Seattle, I am extremely disappointed that the shoulder expansion doesn’t include Ash Way Park & Ride. It can take an extensive amount of time to get from Ash Way To the Lynnwood Park & Ride area each morning.

Leave a Reply

Your email address will not be published. Required fields are marked *

Real first and last names — as well as city of residence — are required for all commenters.
This is so we can verify your identity before approving your comment.

By commenting here you agree to abide by our Code of Conduct. Please read our code at the bottom of this page before commenting.