Beginning Feb. 20, crews started removing large flyover ramps that once carried northbound I-405 traffic to SR 522. Taking down these structures opens the center of the interchange so crews can widen I-405 and continue construction on the I-405/Brickyard to SR 527 Improvement Project .
This work will happen over a sequence of weekend closures stretching into mid-March. While the ramp removal work can happen in most weather conditions, certain steps, such as restriping temporary detours, require dry pavement. The Washington State Department of Transportation will confirm each closure as schedules are finalized.
Upcoming closure schedule
- Feb. 27-March 2: All lanes of eastbound and westbound SR 522 at the I-405 Interchange will close from 10 p.m. Friday, Feb. 27, to 4 a.m. Monday, March 2, to remove the remaining portion of the ramp over SR 522. Crews will start closing lanes as early as 9 p.m.
- As early as March 6-9: All lanes of northbound and southbound I-405 in Bothell will close from Friday night, March 6, to Monday morning, March 9, to remove portions of the ramps over mainline I-405. Times for the closure will be released when the schedule is finalized.
- As early as March 13-16: All lanes of northbound and southbound I-405 in Bothell will close Friday night, March 13, to Monday morning, March 16, to remove the remaining portion of ramps over mainline I-405. Times for the closure will be released when the schedule is finalized.
Detour routes will be signed, but they cannot carry normal SR 522 or I-405 freeway volumes.
People should plan for longer trips and congestion that may extend beyond the immediate closure areas. Travel patterns may shift week to week as work locations change. Travelers with flexibility should consider adjusting travel times or exploring alternate modes where possible.
Real-time information will be available through the WSDOT mobile app and the Travel Center Map or by signing up for WSDOT’s email updates .
