SNOQUALMIE, Wash. — Both directions of State Route 18 will be closed to all traffic for more than five days under the Interstate 90 bridges near Snoqualmie later this month.
From 9 p.m. Thursday, May 15, through 5 a.m. Wednesday, May 21, traffic will not be allowed on either direction of SR 18 beneath the I-90 bridges.
Crews will build the southern end of a new diverging diamond interchange.
Travelers should use other routes and plan for longer travel times during the closure.
The Washington State Department of Transportation chose the dates to avoid busy travel weekends for Mother’s Day on May 11 and Memorial Day on May 26.
If it rains, the work may be rescheduled as it requires dry conditions.
Traffic in both directions of I-90 will not be affected during the closure.
Here’s what to expect, per WSDOT:
Traffic on the eastbound I-90 off-ramp will only be able to turn south onto westbound SR 18. No left turns onto eastbound SR 18/Snoqualmie Parkway will be allowed.
Traffic on the westbound I-90 off-ramp will only be able to turn north onto Snoqualmie Parkway or continue on to the westbound I-90 on-ramp. No left turns onto westbound SR 18 will be allowed.
Eastbound SR 18 traffic must use the eastbound I-90 on-ramp and follow a detour.
Southbound traffic on Snoqualmie Parkway must use the westbound I-90 on-ramp and follow a detour.
Detours
“People can detour around the closure using eastbound and westbound I-90 and loop around at the Preston-Fall City (exit 22) and Southeast North Bend Way (exit 27) interchanges.
“Westbound I-90 freight traffic should use either the Preston-Fall City exit to loop back and take westbound SR 18 or continue on westbound I-90 to southbound I-405. Freight traffic should not use Issaquah city streets or Issaquah-Hobart Road, which are not suitable for semi-trucks. Similarly, eastbound SR 18 freight traffic cannot use Issaquah city streets to access I-90,” WSDOT said in a news release.
