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Buses on shoulder mean faster transit trips on I-5 southbound from Lynnwood

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It’s not your imagination – if you use our region’s congested highways, travel times are increasing, even if you’re riding the bus.

Over the past five years, the speed of ST Express buses throughout the region has slowed by 12 percent. And it’s only going to get worse. Sound Transit expects ST Express travel speed to decrease by another 11 percent by 2022.

This symptom of our fast-growing population makes Sound Transit’s coming light rail expansions critical to the region. Light rail can not only move vastly greater numbers of people—a single train can hold up to 800—but operates free of rising congestion. Over the next 23 years Sound Transit will incrementally build out a 116-mile regional system.

In the meantime, Sound Transit, WSDOT and our regional transit partners are employing creative solutions to keep buses moving as efficiently as possible. This includes looking for highway locations where improvements can allow buses to drive on the shoulders, improving transit speed and reliability.

“Bus on shoulder,” or bus shoulder lanes, is a relatively fast-to-construct and inexpensive solution that is already working in the Bothell area, where Community Transit and ST Express buses use the lanes that run along southbound I-405 between SR 527 and NE 195th and between SR 522 and NE 160th Street.

That operation has saved time for some bus riders, and bus routes using southbound I-5 now will have that benefit.

Starting tonight, contractor crews will begin work to make a stretch of the southbound I-5 shoulder drivable for transit buses. When open, the shoulder lane will help reduce bus trips on that corridor by about 4-5 minutes on days when the freeway is most congested.

The project, a four-mile stretch of the I-5 left-hand shoulder between the Lynnwood Transit Center 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 (ST3) ballot measure.

When this bus shoulder lane is complete this fall, buses will be able to drive on the southbound I-5 left-hand shoulder during the morning commute when traffic in the HOV lane is running substantially slower than posted speeds. Bus drivers will have the option to gain a time advantage by using the shoulder lane instead of remaining in the HOV lane.

Meanwhile, WSDOT is working with transit agencies in Snohomish, South King and Pierce counties on a feasibility study to explore areas along I-5, I-405, SR 167 and SR 518 as possible locations for additional bus shoulder lanes. The feasibility study, also funded under ST3, will be complete in 2019, with any projects it identifies being operational by 2024.

With light rail and bus rapid transit extensions still a few years off, taking advantage of the shoulder is a way to help ensure transit speed and reliability when every minute on the road counts.

Read more here about the upcoming bus on shoulder project for I-5.

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