Travel through Bothell and Woodinville will face major disruptions over the next month as the Washington State Department of Transportation begins four weekends of construction to add a new lane to I-405.
WSDOT closed the old ramps between I-405 and State Route 522 in Bothell late last year. Contractors are now demolishing them, requiring road shutdowns. This weekend brings the least disruptive closure. WSDOT will close westbound SR 522 at I-405 from Friday night into Saturday to remove the shortest section of the old northbound 405 ramp to westbound 522 near the University of Washington Bothell.
The following weekend, both directions of SR 522 at I-405 will close to remove the ramp section over the highway. The next two weekends will bring far more extensive closures. As early as the weekend of March 6 through 9, WSDOT will close both directions of I-405 at SR 522 in Bothell. Northbound drivers will be forced off the freeway and detoured to SR 522 before returning to I-405. Southbound drivers must exit at Canyon Park and take State Route 527 through Bothell to eastbound SR 522 and back to I-405.
Another full closure of I-405 at SR 522 is scheduled for March 13 through 16. WSDOT needs both full weekend closures to remove the flyover ramp. The closures could cause up to an hour of delays in both directions of I-405.
The state is adding a second express toll lane to both directions of I-405 between the Bothell/Woodinville exit and Canyon Park. Contractors need to build a new bridge over SR 522, and the old ramps are in the way. Construction is expected to finish in 2028.
