Crews will close up to four southbound lanes of I-5 in Des Moines and SeaTac starting the night of Monday, Dec. 18, 2023, the Washington State Department of Transportation (WSDOT) announced.

Then, starting Tuesday, Dec. 19 though the morning of Friday, Dec. 22, up to three lanes in each direction of I-5 will close nightly as crews remove formwork from the South 216th Street bridge.

Lane closure information

Monday, Dec. 18 through the morning of Tuesday, Dec. 19:

  • 8 p.m. – Southbound HOV lane closes
  • 9:30 p.m. – Southbound general-purpose lanes begin closing.
  • 11:59 p.m. – All but one southbound lane of I-5 between South 200th Street and SR 516 are closed to traffic.
  • 4:30 a.m. – Southbound lanes begin reopening to traffic.
  • 5 a.m. – All southbound I-5 lanes open.

Tuesday, Dec. 19, nightly, through the morning of Friday, Dec. 22:

  • 8 p.m. – Northbound general-purpose lanes begin closing.
  • 9:30 p.m. – All but two northbound lanes of I-5 between State Route 516 and South 200th Street are closed to traffic. Southbound general-purpose lanes begin closing.
  • 11:30 p.m. – All but two southbound lanes of I-5 between South 200th Street and SR 516 are closed to traffic.
  • 4 a.m. – Northbound lanes begin reopening to traffic.
  • 4:30 a.m. – All northbound I-5 lanes open.
  • 6 a.m. – All southbound I-5 lanes open.

Wednesday, Dec. 20, nightly, through the morning of Friday, Dec. 22:

  • 11:30 p.m. – The southbound on-ramp from SR 516 to I-5 is closed to traffic.
  • 5 a.m. – The southbound on-ramp from SR 516 to I-5 reopens.

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

This work is part of the SR 509 Completion Project.

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.