More Buses Will Travel on the Shoulder to Skip Traffic in Seattle

Soon, Sound Transit buses will start traveling on the shoulder to skip a perpetually congested stretch of I-5. Over a dozen Sound Transit and Community Transit express routes operate on the 2.5-mile stretch.

1 minute read

December 17, 2017, 9:00 AM PST

By James Brasuell @CasualBrasuell


Seattle Freeway

This stretch of I-5 in Lynwood, just north of Seattle, will make even more room for buses this year. | Google Streetview

The Sound Transit Capital Committee have a contract with the Washington State Department of Transportation (WSDOT) that will allow Sound Transit buses to travel on the shoulder of Interstate 5 between 44th Ave W and 236th St SW. Stephen Fesler reports on the project, which is an early action of Sound Transit 3 (ST3).

"Known as 'bus-on-shoulder' (BOS) lanes, these facilities will be designated on inside shoulders adjacent to high occupancy vehicle (HOV) lanes," according to Fesler. "This will allow buses to weave in and out HOV lanes as needed to move closer to maximum highway speeds, expediting riders on an ever-crowed I-5."

The new BOS lanes could be operational by the end of 2018, at a cost of $265,421 for Sound Transit. The new BOS lanes will match existing lanes on I-4-5, and could gain company. "As part of a separate action, the Capital Committee approved a $375,000 feasibility study to evaluate other locations on regional highways that BOS lanes could be implemented, such as SR-167, SR-518, and other portions of I-5 and I-405," adds Fesler.

An article by Yonah Freemark from 2015 provides more background on how bus-on-shoulder service works.

Friday, December 15, 2017 in The Urbanist

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