Coming in September: westbound I-90 down to 1 lane in Issaquah

ISSAQUAH, Wash. — Drivers on westbound Interstate 90 in Issaquah will want to plan ahead next month during a pavement repair project.

A three-lane section of westbound I-90 just east of Issaquah will be reduced to one lane for four consecutive days and five nights.

Work will begin at 9 p.m. on Sunday, Sept. 11, and continue through 5 a.m. on Friday, Sept. 16, while Washington State Department of Transportation crews replace the concrete panels on the left side of I-90.

Reducing the lanes will provide a safe work area for crews.

The following week, from 9 p.m. on Sunday, Sept. 18, to 5 a.m. on Thursday, Sept. 22, westbound I-90 will be reduced to one lane again as crews replace pavement on the right side.

Instead of paving over existing concrete, crews will remove all the concrete panels down to the dirt, then repave with asphalt.

Because of the volume of work needed, the repairs cannot be done only during overnight shifts.

WSDOT said the nearly 45-year-old concrete is cracked so badly that repaving over it is not an option.

“This section of I-90 is located near an old coal mine that was sealed up before the freeway was built. Through the years, water collected in the mine and began seeping under the westbound I-90 lanes. This softened the soil, which eventually led the concrete panels to crack,” WSDOT said in a news release.

The section of westbound I-90 carries about 29,000 vehicles a day. When traffic is forced down to one lane, drivers should expect backups or consider using public transportation, working remotely, carpooling or using another route.