From WSDOT:

Drivers heading to Burien or Sea-Tac Airport should prepare for up to four full closures of southbound State Route 509 over the next seven nights.

Closure details

· Wednesday, April 22 to the morning of Friday, April 24 and Monday, April 27 to the morning of Wednesday, April 29 – All southbound lanes of SR 509 from SR 518/Southwest 148th Street to South 160th Street will be closed from 8 p.m. to 5 a.m. nightly.

· Drivers will follow a short signed detour [onto 1st Avenue S.]. The southbound SR 509 exit to SR 518 and the airport will remain open.

· This work is weather dependent.

During the closures, contractor crews working for the Washington State Department of Transportation will grind and repave sections of the highway near SR 518. The work is part of the SR 509 project to replace the asphalt on a four-mile section of the roadway.