Lane and ramp closures in south King County continue this week

The Washington State Department of Transportation has announced overnight lane and ramp closures on I-5 and SR 516 in the Kent, Des Moines, and SeaTac areas from March 10 to March 14, 2025, as part of the SR 509 Completion Project. These closures are necessary for contractor crews to install concrete barriers and stripe the roadway, impacting traffic flow during the specified hours. Notably, up to four lanes of northbound I-5 will close overnight, and the northbound I-5 to westbound SR 516 ramps will also be closed, with signed detours provided for drivers. This project aims to complete a new tolled highway segment that will connect I-5 to South 188th Street, facilitating better access to the Seattle-Tacoma International Airport. The initial section of the highway is expected to open in summer 2025, marking a significant milestone in regional transportation infrastructure.

By 2029, the entire SR 509 project will be completed, providing crucial links for both local commuters and freight transport. The Puget Sound Gateway Program, which includes this project, seeks to address critical missing links in Washington’s highway network. These developments are essential for improving roadway safety and efficiency in the growing South King County area.