UPDATE: The scheduled closure of the State Route 18 on-ramp to westbound Interstate 90 Wednesday night, Aug. 14, has been delayed. The work will be rescheduled to a later date.
The Interstate 90/State Route 18 Interchange Improvements project reaches a major milestone over the next two weeks when the first ramps of the new diverging diamond interchange open to traffic near the city of Snoqualmie. The first ramp switch will occur overnight Wednesday, Aug. 14, along the SR 18/Snoqualmie Parkway on-ramp to westbound I-90.
During the switch, the existing SR 18 on-ramp to westbound I-90 will close at 9 p.m. Wednesday, Aug. 14. The new ramps will open by 5 a.m. Thursday, Aug. 15. A signed detour during the closure will use eastbound I-90 and loop around at Winery Road/Southeast North Bend Way (exit 27).
Once the new westbound I-90 on-ramps open Thursday morning, people should pay attention to the new striping and signs.
Second ramp switch
The eastbound I-90 off-ramp to SR 18 will close at 9 p.m. Thursday, Aug. 22, and traffic will move to that new ramp beginning at 5 a.m. Friday, Aug. 23. During the closure, people can follow a detour, continuing eastbound on I-90, looping around to westbound I-90 at Winery Road/Southeast North Bend Way (exit 27) and using the off-ramp to SR 18/Snoqualmie Parkway.
The new on- and off-ramps will be the first portion of a new diverging diamond interchange to open to traffic. The full interchange is on schedule to open in late 2024.
Diverging diamond interchange
The diverging diamond interchange was identified by WSDOT in 2016 as the preferred way to improve efficiency and safety at the busy interchange. Once completed, it will be the second diverging diamond interchange in the state and will allow through traffic and left turns at the same time to improve traffic flow and reduce collisions.
Along with building the new interchange, the project, which will finish in late 2025, will:
- Widen two miles of SR 18, providing two lanes in each direction between I-90 and Deep Creek.
- Build a new two-lane bridge over the Raging River next to the existing bridge.
- Construct two new four-lane bridges over Deep Creek and Lake Creek.
- Replace six fish passage barriers with relocated open channel streams.
- Improve habitat connectivity for wildlife, including deer and elk.
Real-time travel information is available via the WSDOT mobile app, the WSDOT Travel Center map or by signing up for WSDOT’s email updates.
[Information provided by the Washington State Department of Transportation]
Comments
this is good but getting the 4 lanes to deep creek is really the key. the traffic backup has become worse and worse.
also, a quick comment–highway 18 is a major highway–it is the freeway connection to eastern washington from tacoma. it really should be interstate 290 and funded by the federal government. AND as part of that, we should NOT have a diverging diamond–there should be freeway exits that do not have stop lights from i-90 to highway 18 (as it was originally designed to have–flyovers–ramps over the roads). i guess we will take what we get but why do so many midwest and eastern states get all these new freeways paid the federal government and we don’t?