Pavement repair project will target damaged sections of SR 18 near Tiger Mountain summit

UPDATE: The start of the work on State Route 18 has been rescheduled to early July. The information has been updated below. 

Project also will repair ramps and make accessibility improvements on I-5 and I-405 ramps in SeaTac, Tukwila and Kirkland

KING COUNTY – The second phase of a regional pavement repair project beginning this spring will grind down damaged sections of State Route 18 between Issaquah-Hobart Road and Deep Creek and replace them with new asphalt. Repairing damage caused by winter weather and heavy use will help preserve a 5-mile stretch of this vital connection between southern and eastern King County and create a smoother ride.

Beginning in early July, contractor crews working for the Washington State Department of Transportation will close SR 18 between Issaquah-Hobart Road and I-90 up to seven times in each direction (14 total). Closures will begin nightly at 11 p.m. Monday through Thursday and last until 4 a.m. for westbound travel and 5 a.m. for eastbound. Both directions will not close at the same time.

Signed detours will guide people around the SR 18 closures. During these closures, freight traffic should use interstates 90 and 405 and avoid using Issaquah-Hobart Road and Front Street in Issaquah, as these local roads are not suitable for heavy truck traffic. Only local traffic will be allowed south of I-90 during westbound closures of SR 18.

I-5 and I-405 ramp repairs and accessibility improvements

Crews also will grind damaged sections and place new asphalt along ramps at four I-5 and I-405 interchanges in SeaTac, Tukwila and Kirkland as part of the project. Work at two of those sites also includes retrofitting sidewalk curb ramps to meet Americans with Disability Act requirements and updating traffic signals.

People traveling through the interchanges during construction can expect daytime shoulder and sidewalk closures and nighttime lane reductions and ramp closures. Detours will be available for pedestrians during sidewalk closures and for drivers during ramp closures.

Work began this week, with nighttime lane closures near the I-5 off-ramps to South 188th Street and Orillia Road South (exit 152) in SeaTac. The project is expected to finish in early September when crews return to all five sites to install permanent lane striping.

Schedule updates will be available on the project webpage, WSDOT's Travel Center map, the WSDOT mobile app and by signing up for King County email updates.

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