Overnight lane and ramp closures on I-5 in the Des Moines, SeaTac, and Kent area continue Monday, Mar. 3 through the morning of Friday, Mar. 7, 2025, according to the Washington State Department of Transportation (WSDOT).
The closures on I-5 will allow contractor crews working for WSDOT to install concrete barriers and stripe the roadway.
This work is part of the State Route 509 Completion Project.
I-5 lane closure information
Monday, March 3 through the morning of Tuesday, March 4:
- 9 p.m. to 4 a.m. – Up to two lanes of northbound I-5 will close overnight between SR 516 (Exit 149) and South 200th Street/Military Road South (Exit 151).
- 11:30 p.m. to 6 a.m. – Up to two lanes of southbound I-5 will close overnight between South 200th Street/Military Road South (Exit 151) and SR 516 (Exit 149).
Tuesday, March 4 through the morning of Friday, March 7:
- 9 p.m. to 4 a.m. – Up to four lanes of northbound I-5 will close nightly between SR 516 (Exit 149) and South 200th Street/Military Road South (Exit 151).
I-5 ramp closure information
Monday, March 3 through the morning of Thursday, March 6:
- 9:30 p.m. to 3:30 a.m. – The northbound I-5 to SR 516 on-and off-ramps will close nightly. A signed detour will be in place.
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 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 2029.
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.
