A new shoulder lane open for evening commutes on northbound I-405 between Bothell and Lynnwood is the first of several planned shoulder expansions on state highways in the coming years.
One week in, the new shoulder lane on Interstate 405 — the first of several planned shoulder expansions on state highways in the coming years — has reduced travel times, although officials stress that it is too early to make any official conclusions.
On April 24, the Washington State Department of Transportation (WSDOT) opened a 1.8-mile section of the shoulder of northbound I-405, between Highway 527 in Bothell and Interstate 5 in Lynnwood.
The shoulder, which will generally be open only during the evening commute, adds a fourth lane of traffic to I-405, to go with the two existing regular traffic lanes and one express toll lane.
About 1,000 cars per hour get on I-405 at the 527 onramp, which previously created a forced merge into traffic and slowed down the roadway. With the shoulder lane open, cars are able to drive from the ramp straight onto the shoulder, and continue as if it’s a regular lane.
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Open to buses, but not heavy trucks, the shoulder lane is the first project to be funded with revenue from I-405’s express toll lanes, which brought in $15.6 million in their first year of operation, triple the expected amount.
Those toll lanes — where drivers can choose to pay a toll that…