Drivers across western Washington should prepare for significant delays this weekend as multiple construction projects bring lane reductions, ramp closures, and full highway closures to some of the region’s busiest roadways.
I-405 lane closures could slow trips to Sea-Tac Airport
Anyone traveling to Seattle-Tacoma International Airport from Tukwila this weekend should expect delays on southbound I-405.
Washington State Department of Transportation crews will close two southbound lanes and the southbound I-405 HOV off-ramp to northbound I-405 while crews pave the roadway as part of the Renton to Bellevue Widening Project.
The closures are scheduled from 7 p.m. Saturday until 1:30 p.m. Sunday.
Drivers heading to the airport are encouraged to consider taking Link light rail or using I-5 instead.
Eastbound SR 520 closing for the weekend
The second weekend-long closure of eastbound SR 520 begins Friday night.
Starting at 11 p.m. Friday, eastbound SR 520 will close between I-5 and Montlake Boulevard for construction work.
Drivers attempting to access eastbound SR 520 from I-5 should consider using I-90 as an alternate route. Heavy traffic is expected throughout the closure.
Aurora Bridge lane reductions
Drivers using the Aurora Bridge should also plan for delays this weekend.
The two right southbound lanes on SR 99 across the Aurora Bridge will close from 5 a.m. to 11:30 a.m. Saturday for maintenance work. On Sunday, the two northbound lanes will close from 5 a.m. to 11:30 a.m.
Traffic backups are expected on SR 99 and potentially on I-5 as drivers seek alternate routes. Motorists may want to consider using 15th Avenue Northwest and the Ballard Bridge instead.
I-5 Express Lanes closing through Seattle
The I-5 Express Lanes in Seattle will be fully closed from 11 p.m. Friday until 5 a.m. Monday.
The closure will allow crews working on the Revive I-5 Project at the Ship Canal Bridge to access the underside of the bridge for drainage improvements.
Drivers planning northbound trips through Seattle should be aware of the closure and expect changes to normal traffic patterns throughout the weekend.
SR 99 tunnel closed overnight Friday
Drivers traveling into downtown Seattle late Friday night should also note an overnight closure of the SR 99 tunnel.
The tunnel will close from 10 p.m. Friday until 6 a.m. Saturday morning.
Officials recommend planning ahead and using alternate routes during the closure.
With several major transportation projects happening simultaneously, drivers should expect congestion across the region and give themselves extra travel time before heading out this weekend.
©2026 Cox Media Group
