Snohomish County transit riders heading south on I-5 will soon be able to navigate through the morning congestion more quickly, thanks to the newly completed transit-only shoulder lane.

Starting Monday, Nov. 12, buses will be able to travel on the 1.5-mile stretch of the southbound I-5 inside shoulder lane between the Lynnwood Transit Center and the Mountlake Terrace Freeway Station. This lane comes from the new bus-on-shoulder program funded by WSDOT and Sound Transit, and is the first Sound Transit 3 construction project to come online following voter approval of the regional transit measure in 2016.

“Snohomish County commuters endure some of the country’s worst traffic on I-5, 405 and US2,” said Sound Transit Board Chair Dave Somers. “This new bus lane, funded through ST3 and an investment from WSDOT, is the product of collaboration between regional partners to provide some much-needed relief for our commuters. As light rail makes its way north toward Snohomish County, we will continue to look for ways to keep people moving and to provide commuting options. This is the public’s investment at work!

Commuters may have already seen buses in the shoulder lane the last two weeks while transit operators train on this new, slightly narrower lane. Beginning Monday, buses will only use the shoulder lane under the following circumstances:

• During the weekday morning commute (Monday through Friday, 6-9 a.m.).
• When traffic in the adjacent HOV lane is running substantially slower than posted speeds.
• When a bus driver believes he or she will gain a time advantage by using the shoulder lane rather than remaining in the HOV lane.
• Buses will operate no more than 15 mph above the speed of HOV traffic, with a maximum speed of 35 mph.

Buses driving in the shoulder lane will also have their flashers on to be highly visible to other drivers. The shoulder lane is clearly marked with “Authorized Transit Only” signs. Non-transit vehicles may not drive in the shoulder lane, but can still use it as usual in emergencies.

Community Transit and Sound Transit buses already use the shoulder lane on southbound I-405 when the morning commute is heavily congested. That operation has saved time for some bus riders, and bus routes using southbound I-5 now have that benefit.

“Our drivers and trainers have developed procedures to ensure safe driving on shoulder lanes with a goal of improving schedule reliability for our transit riders,” said Community Transit CEO Emmett Heath. Community Transit operates 19 of its own bus routes to Seattle and UW, and four Sound Transit Express bus routes to Seattle.

“Transit improvements don’t have to be large or complicated to make a difference for people who travel our congested roads every day,” said Sound Transit CEO Peter Rogoff. “Before light rail reaches Snohomish County in 2024, this is one way we’re able to reduce travel time for I-5 bus commuters.”