SNOQUALMIE, Wash. — After nearly four years of construction, the Interstate 90/State Route 18 interchange project is finished.
This was the final weekend of road work and the Washington State Department of Transportation (WSDOT) says its contractor completed paving and striping about 20 hours ahead of schedule.
SR 18/Snoqualmie Parkway reopened under I-90 Sunday morning.
Growth in Snoqualmie Valley has made the I-90/SR 18 interchange one of the busiest in the state.
The $188 million improvement project aimed to cut down on backups and crashes in the area.
In four years, crews have:
- Created a diverging diamond interchange
- Widened two miles of SR 18, adding two lanes in each direction
- Added a traffic signal-controlled U-turn just west of the interchange
- Built a new 2-lane bridge over Raging River next to the existing bridge
- Added two 4-lane bridges, one at Deep Creek and one at Lake Creek.
- Replaced fish passage barriers with relocated, open-channel streams
- Improved habitat connectivity for wildlife, including deer and elk
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