Weekend travelers should expect lane closures and traffic delays throughout the Seattle area this weekend as crews take advantage of summer weather to perform scheduled maintenance and construction.

Washington State Department of Transportation (WSDOT) crews will work on the Highway 99 tunnel, the Aurora Bridge, and Interstate 5 through Seattle. Weekend work will also affect Interstate 90 and Interstate 405.

Highway 99

The southbound lanes of the Highway 99 tunnel will close Friday at 10 p.m. and reopen Saturday at 8 a.m. for regular monthly maintenance.

Meanwhile, rescheduled paving work will limit traffic on the Aurora Bridge on Highway 99 through Seattle to just one lane in each direction. Lanes will close starting at 7 p.m. Friday and open 5 a.m. Monday.

Crews will shift traffic to scrape off asphalt, check the condition of the concrete underneath, make any needed repairs and repave the deck on the north end of the bridge.

The repaving had been postponed due to rainy weather last weekend.


Another closure is scheduled for next weekend, Aug. 23-26, if weather permits. More closures could be in the cards, depending on whether crews find large repairs are needed.

Interstate 5

Crews will close two lanes of southbound I-5 over the Ship Canal Bridge near the University of Washington to repair the bridge deck.

The lanes will close 10 p.m. Friday and Saturday and reopen 9 a.m. the next day.

Sound Transit I-405 closures

Crews in Bellevue this weekend will continue disassembling the temporary columns and beams used during construction of the new Sound Transit light-rail bridge over I-405, requiring closures.

Starting at 10 p.m. Friday until just before midnight Saturday, the northbound I-405 offramp to Northeast Eighth Street and the Northeast Fourth Street onramp to northbound I-405 will be closed.

And around midnight Saturday to 5 a.m. Monday, all northbound I-405 lanes between Main Street and Northeast 10th Street will close. The northbound I-405 HOV offramp and the southbound HOV onramp to and from Northeast Sixth Street will also close.


Drivers will be directed to the collector-distributor lanes as a detour.

I-90 floating bridge

All lanes of eastbound I-90 between Seattle and Mercer Island will close from 10 p.m. Saturday to 5 a.m. Sunday for inspections and maintenance.

The closures include all ramps to eastbound I-90 between I-5 in Seattle to Island Crest Way on Mercer Island. The Island Crest Way onramps will remain open.

WSDOT crews will inspect safety systems inside the Mount Baker Tunnel, as required by the federal government.