Nightly I-5 and SR 509 lane closures in South King County will begin Monday, June 3

Preparations are underway to open the new South 216th Street bridge over I-5 in SeaTac to two-way traffic in early June, which means that crews working for the Washington State Department of Transportation will close lanes on northbound and southbound I-5 nightly beginning Monday, June 3, 2024.

The lane closures will allow crews to safely remove scaffolding around the new bridge.

In addition, crews are performing site surveys around the State Route 509 and South 160th Street interchange in Burien as they prepare to begin interchange improvement construction later this year.

Work in both locations is part of the SR 509 Completion Project.

I-5 lane closure information

Monday, June 3 through the morning of Friday, June 7

• 9:30 p.m. to 4 a.m. – Up to three lanes of northbound I-5 will close nightly between South 272nd Street (Exit 147) and South 200th Street/Military Road South (Exit 151).
• 11:30 p.m. to 6 a.m. – Up to four lanes of southbound I-5 will close nightly between South 200th Street/Military Road South (Exit 151) and South 272nd Street (Exit 147).

SR 509 lane closure information

Monday, June 3 through the morning of Saturday, June 8

• 8 p.m. to 5 a.m. – The right lane of southbound SR 509 between South 160th Street and Des Moines Memorial Drive South will close nightly.
• 7 p.m. to 5 a.m. – The right lane of northbound SR 509 between Des Moines Memorial Drive South and South 160th Street will close nightly.

This work is weather-dependent and may be rescheduled in the event of rain.

SR 509 Completion Project information

The SR 509 Completion Project builds 3 miles of new tolled highway between I-5 and South 188th Street near the south end of Seattle-Tacoma International Airport. The new highway will be completed in stages. The portion currently under construction between I-5 and 24th Avenue is scheduled to open in 2025. The final stage will build the remaining 2 miles of the expressway between 24th Avenue South and South 188th Street. The entire project is planned for completion by 2028.

Puget Sound Gateway Program overview

The SR 509 Completion Project is part of WSDOT’s Puget Sound Gateway Program, which also includes the SR 167 Completion Project in Pierce County. Combined, the two completion projects finish critical missing links in Washington’s highway and freight network.

Know before you go

Before heading out the door, travelers can find the latest information on the WSDOT app, the real-time travel map, or by subscribing to WSDOT’s email and text alerts.