Although some Seattle-area road work will be on pause for Seafair weekend, some road closures will impact travel across the Puget Sound region, including full closures on State Route 18 and Interstate 405.
SR 18/I-90 Interchange
In Snoqualmie, State Route 18 will close under the Interstate 90 bridges from 8 p.m. until 6 a.m. tonight through Sunday morning. Crews are performing the shutdown to install permanent striping throughout the new diverging diamond interchange.
While the main route is blocked, all right-turning ramps near the interchange will remain open. Traffic on the eastbound and westbound Interstate 90 off-ramps will be restricted to right turns only during the Snoqualmie closure.
Eastbound State Route 18 traffic will follow a detour using the eastbound Interstate 90 on-ramp.
Drivers can navigate around the area by using interchanges at Highpoint Way to the west or Southeast North Bend Way and Winery Road to the east.
Westbound SR 16
Commuters using the Tacoma Narrows Bridge should expect delays on Saturday.
Two right lanes of westbound State Route 16 and the Jackson Avenue on-ramp will be closed from 6 a.m. to 8 p.m. The work is necessary for crews to reinforce bridge joint repairs that were originally completed last month. There are no direct detours available for these lane closures on the bridge, so plan extra time.
Northbound I-405
In Tukwila, northbound Interstate 405 will be closed from Interstate 5 to State Route 18/ West Valley Highway. This maintenance project will take place from 9 p.m. Saturday to 6 a.m. Sunday. Detour signs will be posted to guide travelers. Those heading to northbound Interstate 405 from Interstate 5 will be directed to State Route 181 at Exit 1 near Southcenter.