I-405 construction

Last update: 3:45 p.m. Friday, Sept. 13

This information changes frequently. Please check back often. Travelers can also call 5-1-1 for real-time traffic and weather updates. If you have questions or comments about I-405 in Washington state that are not addressed by these resources, please contact the I-405 Project Office at 425-456-8585.

I-405/SR 167 Interchange Direct Connector - #8811

Highway: I-405    Region: Northwest    County: King    Location: Milepost(s) 2.32 – 3.96
Contact: Craig Smiley, Communications, 425-456-8624
Description: WSDOT contractor crews are building a new flyover ramp connecting the HOT lanes on SR 167 to the carpool lanes on I-405 in Renton. This ramp will improve traffic flow and safety at this critical interchange.
Project webpage
Work schedule:

Lane closures

  • Tuesday, Sept. 3, to the morning of Wednesday, Sept. 4 – Two lanes of southbound I-405 between Talbot Road South and SR 167 will be closed from 11 p.m. to 4:30 a.m.
  • Wednesday, Sept. 4, to the morning of Friday, Sept. 6 – Up to two lanes of northbound I-405 between SR 167 and Talbot Road South will be closed from 10 p.m. to 4:30 a.m.

Ramp closures

  • Wednesday, Sept. 4, to the morning of Thursday, Sept. 5 – The northbound I-405 ramp to southbound SR 167 will be closed nightly from 10 p.m. to 4:30 a.m. A signed detour will be in place.
  • Wednesday, Sept. 4, to the morning of Thursday, Sept. 5 – The southbound SR 167 ramp to northbound I-405 will be closed nightly from 10 p.m. to 4:30 a.m. A signed detour will be in place.
  • Thursday, Sept. 5, to the morning of Friday, Sept. 6 – The northbound SR 167 HOV ramp to northbound I-405 will be closed nightly from 8 p.m. to 5 a.m. A signed detour will be in place.
  • Thursday, Sept. 5, to the morning of Friday, Sept. 6 – The southbound I-405 off-ramp to Rainier Avenue South will be closed nightly from 10 p.m. to 4 a.m. A signed detour will be in place.
  • Thursday, Sept. 5, to the morning of Friday, Sept. 6 – The southbound I-405 ramp to southbound SR 167 will be closed nightly from 11 p.m. to 4:30 a.m. A signed detour will be in place.
  • Friday, Sept. 6, to the morning of Saturday, Sept. 7 – The northbound SR 167 ramp to northbound I-405 will be closed nightly from 10 p.m. to 4:30 a.m. A signed detour will be in place.

* Please note that not all the listed ramps will be closed at the same time. Select ramps will remain open to maintain a working detour for the traveling public.

City street closures

  • Wednesday, Sept. 4, to the afternoon of Friday, Sept. 6 – One lane of northbound East Valley Road between Southwest 19th Street and Taylor Avenue Southwest will be closed from 8 a.m. to 3:30 p.m.

Sound Transit's East Link Extension - E320

Highway: I-405    Region: Northwest    County: King    Location: Milepost(s) 10.65
Contact: Jason Hampton, Sound Transit, 206-903-7177
Description: Sound Transit crews are constructing the East Link light rail extension from Seattle to Redmond.
Project webpage
Work schedule:

  • Sunday, September 15, to the morning of Tuesday, September 17 – The northbound I-405 ramp to westbound I-90 will close from 10 p.m. to 5 a.m.
  • Sunday, September 15, to the morning of Tuesday, September 17 – The southbound I-405 ramp to westbound I-90 will close from 10 p.m. to 5 a.m.
  • Sunday, September 15, to the morning of Tuesday, September 17 – The southbound I-405 ramp to the westbound I-90 HOV lane will close from 8 p.m. to 5 a.m.

Sound Transit's East Link Extension - E335

Highway: I-405    Region: Northwest    County: King    Location: Milepost(s) 10.65 - 14.85
ContactJay Cooper, WSDOT Regional Transit Coordination, 206-716-1102; Ryan Lescouflair, Sound Transit, 206-689-4798
Description: Sound Transit crews are constructing the East Link light rail extension from Seattle to Redmond.
Project webpage
Work schedule:

  • No work scheduled at this time.

Renton to Bellevue Culvert Surveillance Project

Highway: I-405    Region: Northwest    County: King    Location: Milepost(s) 10.65 - 11.25
Contact: Craig Smiley, Communications, 425-456-8624
Description: WSDOT contractor crews will inspect storm drains along I-405 from Renton to Bellevue.
Work schedule:

  • No work scheduled at this time.

I-405 - Drilling from SR 522 to SR 527

Highway: I-405    RegionNorthwest    County: King    Location: Milepost(s) 23.3 - 26.75
Contact: Thomas Charlson, communications, 206-440-4699
Description: WSDOT crews are performing drill work from SR 522 to SR 527.
Work schedule:

  • No work scheduled at this time.