Travelers in south King County should prepare for two weekends of reduced lanes and ramp closures at the Interstate 405/State Route 167 interchange, starting this Friday evening, Aug. 17.

Both sets of closures include work beginning Friday evening and running through early Monday morning – so all weekend traffic will be affected by the I-405/SR 167 Interchange Direct Connector Project work. The closures are expected to cause significant delays. The Washington State Department of Transportation is urging travelers to plan ahead and prepare for delays and detour routes.

“We would typically see over 500,000 vehicles drive through this area on an average weekend, so we’re really urging travelers to plan ahead or alter trips if possible,” said I-405 Program Administrator Kim Henry. “This could lead to delays of up to 30 to 45 minutes and backups of up to five to seven miles – and the backups could affect not only I-405 in Renton, but I-5 as well.”

To help avoid congestion and keep traffic flowing travelers can:

  • Allow extra time for travel
  • Consider taking public transportation or carpooling
  • Take alternate routes
  • If possible, reschedule discretionary trips
  • Travel early in the morning or late in the evenings when traffic volumes tend to be lower

Aug. 17-20 Northbound I-405 Lane Reductions:
Contractor crews will repave and restripe sections of I-405 between SR 167 and Talbot Road South/SR 515. Closure dates and times are:

  • 11 p.m. Friday, Aug. 17 to 5 a.m. Monday, Aug. 20 – Northbound I-405 will be reduced to two lanes between SR 167 and Talbot Road South/SR 515.
  • 11 p.m. Friday, Aug. 17 to 5 a.m. Saturday, Aug. 18 – The northbound I-405 ramp to northbound SR 167/Rainier Ave. South will be closed. A signed detour will be in place.
  • 11 p.m. Friday, Aug, 17 to 5 a.m. Monday, Aug. 20 – The southbound SR 167 ramp to northbound I-405 will be closed. A signed detour will be in place.

Aug. 24-27 Southbound SR 167 Full Closure:
During the second weekend of work, crews will install a new culvert under SR 167 to improve fish passage through the area. From 8:30 p.m. Friday, Aug. 24 to 5 a.m. Monday, Aug. 27, crews will fully close the following:

  • All lanes of southbound SR 167 between the I-405 interchange and South 180th Street
  • The northbound I-405 ramp to southbound SR 167
  • The southbound I-405 ramp to southbound SR 167
  • The southbound SR 167 ramp to northbound I-405

All closures are dependent on dry weather and could be rescheduled due to rain.

Detour routes
Detour routes have been established where possible, but travelers should expect heavier-than-normal traffic along those routes during the closures.

Know before you go
Travelers can get real-time traffic conditions before heading out the door with the WSDOT traffic app and by checking the WSDOT Traffic Twitter feed.

Scott Schaefer

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