Update: Overnight ramp closures, detours at I-5/SR 18 interchange May 3-5 and May 2 on SR 509

UPDATE: Work rescheduled for week of May 1

FEDERAL WAY – Evening travelers in south King County should add additional time or adjust routes the week of May 1 for ramp and/or lane closures in two locations, including State Route 509 and the Interstate 5/State Route 18 interchange in Federal Way.

The closures are for work to improve pavement surface and travel along the routes. The bulk of ramp or lane closures are May 3-5 on I-5/SR 18 at the Federal Way interchange and will include marked detours for full closures. The detours vary by location, but the longest would add 13 miles to travel routes. Travelers also can expect overnight lane closures along SR 509 in Federal Way, Tuesday, May 2.

Closures May 2-5

Overnight Tuesday, May 2

  • SR 509 SW Dash Point Road area will be reduced to a single lane in each direction from 9 p.m. Tuesday, May 2, to 5 a.m. Wednesday, May 3.

Overnight Wednesday, May 3

All these closures are 9 p.m. Wednesday, May 3, to 5 a.m. Thursday, May 4 - marked detours available.

  • The northbound I-5 ramp to eastbound SR 18
  • The northbound I-5 ramp to westbound SR 18
  • The westbound SR 18 ramp to northbound I-5

Overnight Thursday, May 4

  • The southbound I-5 ramp to eastbound SR 18 will close 9 p.m. to 11:59 p.m. Thursday, May 4. A detour will be available.
  • The left lane of the westbound SR 18 ramp to southbound I-5 will close 11:59 p.m. Thursday, May 4, to 5 a.m. Friday, May 5.

This work may be rescheduled in the event of rain or inclement weather.

Regionwide summer repairs

This work is part an overall Washington State Department of Transportation project to improve more than 30 miles of seven highways in King and Snohomish counties during the next few months.

Overall, the project will repair ramps at six I-5 interchanges and one along I-405. Additionally, this project will repair pavement on US 2 near Gold Bar, SR 9 between Woodinville and Snohomish, SR 99 in Everett, SR 164 in Auburn, SR 509 in Federal Way, SR 513 in Seattle and SR 527 between Everett and Bothell. Contractor crews from Granite Construction will seal cracks and repair damaged pavement and markings, creating a smoother ride for travelers.

Travelers can receive real-time travel information via the WSDOT mobile app, the real-time travel map, or by following the WSDOT Traffic Twitter account.

Slow down – lives are on the line. 

In 2023, speeding continued to be a top reason for work zone crashes.

Even one life lost is too many.

Fatal work zone crashes doubled in 2023 - Washington had 10 fatal work zone crashes on state roads.

It's in EVERYONE’S best interest.

95% of people hurt in work zones are drivers, their passengers or passing pedestrians, not just our road crews.