I-90 will be reduced to a single lane in each direction for two weeks just east of Snoqualmie Pass while crews remove the 64-year-old snowshed.
Washington State Department of Transportation is also building detours in preparation for the 2014 construction season.
"We can't stress how important it is for drivers to know before they go and plan ahead before heading out the door," said Don Whitehouse, WSDOT regional administrator.
He said drivers may face delays up to two hours long. Traveling at night or early in the morning is your best bet. Even better, find an alternate route or postpone your trip until after April 25.
The work is part of a $551 million project that builds "a wider, safer and more reliable stretch of I-90" from Hyak to Keechelus Dam, according to WSDOT.
WSDOT closure details:
I-90 Snoqualmie Pass MP 56-61: Two lanes will be open in both directions on Friday between the hours of 9 am to 9 pm. At 9 pm, one lane travel resumes. On Sun. at 11 am, two lanes will be open for WB traffic and one lane will be open EB until 9 p.m. At that time, the lane restrictions will revert back to one lane in each direction until the next weekend.
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