Highway 18 westbound closed this weekend, with more detours coming

Westbound Highway 18, one of the state's busiest routes on warm weekends, is closed from Interstate 90 to Issaquah-Hobart Road for 2 miles of paving, which is expected to last until 5 a.m. Monday.

This is the second weekend of five planned ramp closures at or near Exit 25 where I-90 meets Highway 18, as the Washington State Department of Transportation continues with interchange reconstruction, widening of a dangerous stretch of Highway 18 to four lanes, and fish-passage projects.

A new asphalt layer is also being applied this spring, as contractors near the finish line of the four-year, $188 million project.

A more localized closure, affecting just the interchange, is scheduled at 9 p.m. Friday, May 8, until 5 a.m. Monday, May 11, blocking ramps and lanes from eastbound I-90 to westbound Highway 18.

Similarly, on the following weekend, ramps will close from both Highway 18 and Snoqualmie Parkway to eastbound I-90 from 9 p.m. Friday, May 15, until 5 a.m. Monday, May 18.

Truckers are advised not to use Issaquah-Hobart Road and Issaquah city streets as a detour. Last weekend, at least one semi was photographed getting stuck while turning at Issaquah-Hobart Road. Highway 169, I-90, Interstate 405 and Highway 900 are available for detouring.

During this weekend's closure (which began 9 p.m. Thursday) drivers will find detours and confusion around the I-90 interchange that leads to Highway 18. Offramps are closed from westbound I-90 to westbound Highway 18 and also to Snoqualmie Parkway leading to the town of Snoqualmie. WSDOT advises drivers to keep going on I-90, take the High Point exit, then backtrack using eastbound I-90, following a signed detour to reach the town, according to WSDOT.

With local circulation disrupted, Snoqualmie local drivers were flocking to the North Bend exit Saturday afternoon, congesting the westbound I-90 offramp there - and finding more than a mile of slowdowns and brake lights on Highway 202, in both directions, between North Bend and Snoqualmie, according to the online state traffic map.

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This story was originally published May 2, 2026 at 11:39 PM.