Contractor selected for I-90/S.R. 18 interchange project in Washington State

Jan. 17, 2022

The $190 million project is funded through gas tax funds and the 2015 Connecting Washington transportation fund

The Washington State Department of Transportation (WSDOT) recently announced the selection of a design-build contractor for the I-90/S.R. 18 interchange improvement project near North Bend.

Aecon Pacific Northwest Inc. submitted the best value proposal to complete the design and build the project following a competitive evaluation process, WSDOT said in a news release.

“Aecon has built large highway, civil and private projects across the U.S. and Canada,” WSDOT Project Engineer Mark Allison said in a statement. “This is a significant project and one the community has anticipated for a long time. We look forward to working with Aecon to build an interchange that will serve people for many years to come.”

The I-90/S.R. 18 project will feature a diverging diamond interchange, which improves the flow of traffic by reducing the number of traffic signals and offering more free turns for drivers entering and exiting the interstate.

The I-90/S.R. 18 project also includes:

  • Widening approximately 2 miles of SR 18 from the interchange to Deep Creek, creating two lanes in each direction
  • Construction of a new four-lane bridge over Deep Creek and a new two-lane southbound bridge over Raging River
  • Adding a dedicated right turn lane from southbound Snoqualmie Parkway to westbound I-90

The $190 million project is funded through pre-existing gas tax funds and the 2015 Connecting Washington transportation fund, which is a $16 billion investment that enhances the statewide transportation system and maintains critical infrastructure.  

Construction is expected to begin later this year with completion in 2025.


SOURCE: Washington State Department of Transportation