Northbound I‑405 reopens early in Bothell amid major corridor upgrades

Both northbound and southbound lanes of I-405 at the SR 522 interchange reopened early Monday morning after a scheduled weekend closure.

The northbound side opened at approximately 2 a.m. Monday, roughly two hours ahead of schedule. Southbound lanes had already reopened Sunday afternoon, according to the Washington State Department of Transportation (WSDOT).

Improvements to I‑405

The work is part of the I‑405/Brickyard Improvement Project, a multi‑year effort to ease congestion and improve travel along 4.5 miles of the Bothell corridor. Officials said the upgrades will also add direct‑access ramps to the express toll lanes at SR 522 and SR 527 and build new transit stations to support the voter‑approved Stride bus rapid transit system. 

The project has a budget of about $834 million and is expected to be finished in 2028, alongside the expansion of the regional transit system.

While this weekend’s full closure is over, drivers should continue to expect periodic lane and ramp closures as work progresses. During full closures, backups of two to three miles and delays of up to an hour can occur along I‑405 and adjacent routes. Pedestrians and cyclists who use the Sammamish River Trail may face short closures and reroutes while crews build the new interchange structures next to the trail, officials said.

Related Improvements on SR 522

Nearby, the state is also planning future upgrades to SR 522 between Paradise Lake Road and the Snohomish River. The project is still in the design phase with no construction funding secured, but it would widen the highway to two lanes in each direction, build a new eastbound bridge, and replace the signalized intersection at Paradise Lake Road with an interchange to improve safety and traffic flow.

That SR 522 project is separate but reflects ongoing efforts to improve transportation flow on key east‑west routes connecting communities from Woodinville to Monroe.

Drivers are encouraged to check real‑time traffic updates on the WSDOT app or the agency’s travel map as construction continues through the spring and beyond. 

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