Motorists traveling eastbound and westbound Interstate 90 near Snoqualmie should prepare for overnight delays from Monday, June 3, through Friday, June 7.
The delays will occur as crews install support structures for new overhead signs near the State Route 18 interchange. These new signs are part of the I-90/SR 18 Intersection Improvements project, which aims to facilitate traffic flow through a new diverging diamond interchange.
Details of Lane Closures and Rolling Slowdowns
Drivers should expect the left two lanes on both eastbound and westbound I-90 to close, accompanied by rolling slowdowns as contractor crews working for the Washington State Department of Transportation (WSDOT) lift the new support structures, known as sign bridges, into place above I-90.
I-90 Lane Closures and Rolling Slowdowns Schedule
Monday, June 3, to Tuesday Morning, June 4:
- 9 p.m. to 5 a.m.: The two left lanes of westbound I-90 will close near SR 18.
Tuesday, June 4, to Wednesday Morning, June 5:
- 9 p.m. to 5 a.m.: The two left lanes of eastbound and westbound I-90 will close near SR 18.
- 11:59 p.m. to 4 a.m.: Intermittent rolling slowdowns on westbound I-90 beginning at the 468th Avenue Southeast interchange (exit 34).
Wednesday, June 5, to Thursday Morning, June 6:
- 9 p.m. to 5 a.m.: The two left lanes of eastbound I-90 will close near SR 18.
- 11:59 p.m. to 4 a.m.: Intermittent rolling slowdowns on eastbound I-90 beginning at the East Sunset Way/Highland Drive Northeast interchange (exit 18).
Thursday, June 6, to Friday Morning, June 7:
- 9 p.m. to 5 a.m.: The two left lanes of eastbound and westbound I-90 will close near SR 18.
During these rolling slowdowns, traffic control vehicles and the Washington State Patrol will lead drivers through the work zone at reduced speeds, allowing crews to safely lift and secure the sign bridges over I-90 lanes.
Diverging Diamond Interchange to Enhance Traffic Flow
The new diverging diamond interchange, identified by WSDOT in 2016 as the optimal solution for improving efficiency and safety at the I-90/SR 18 interchange, is set for completion in late 2024.
It will be the second such interchange in Washington state, designed to allow simultaneous through traffic and left turns, thereby keeping traffic moving smoothly.
In addition to the interchange, the $188 million project will widen approximately two miles of SR 18 south of I-90 to two lanes in each direction, further enhancing traffic flow and safety.
Stay Informed with Real-Time Travel Updates
For real-time travel information, motorists can use the WSDOT mobile app, check the WSDOT Travel Center Map, or sign up for WSDOT’s email updates.
Travelers are encouraged to stay alert and plan for extra travel time during these nighttime construction activities. WSDOT appreciates the public’s patience and cooperation as they work to improve the highway infrastructure.
