Seattle Quietly Unveils New Interstate Lane

The Washington Department of Transportation expanded part of I-5 in hopes of reducing a common traffic bottleneck.

1 minute read

August 2, 2023, 11:00 AM PDT

By Diana Ionescu @aworkoffiction


View of Interstate 5 with light traffic and downtown Seattle skyline in background

Interstate 5 in downtown Seattle. | Christopher Boswell / Adobe Stock

“Drivers on Interstate 5 will endure less weaving and fewer waves of brake lights entering downtown Seattle, after the state finally widened the original northbound two-lane mainline to three lanes at Seneca Street,” reports Mike Lindblom for The Seattle Times.

The Washington State Department of Transportation (WSDOT) opened the project, in the works since 2007, “without fanfare” last weekend. “There wasn’t much hype because some features aren’t finished yet, spokesperson Amy Moreno said.”

According to the article, “Some drivers could find longer delays, because ramp-metering lights will operate in the collector-distributor lanes, where traffic from Interstate 90 merges into I-5 right of the mainline, as well as metering from the Cherry Street onramp.” Lindblom also points to the possibility of induced demand encouraging more drivers to take the new lane. “WSDOT doesn’t have any recent modeling or traffic predictions available for this long-developing project,” Lindblom notes.

Tuesday, August 1, 2023 in The Seattle Times

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