I-5 - Mounts Rd. to Steilacoom-DuPont Rd. - Corridor Improvements

Project news

  • Thank you to the 140+ participants who attended the April 11 WSDOT Open House (pdf 733 kb), held at Pioneer Middle School in DuPont! If you couldn't attend the event, that's ok! Below you will find the open house display boards.
  • April 11 Open House Display Boards
  • View the Project photos page for proposed design visualizations. All proposed designs are subject to change.
  • View the Feasibility Report (pdf 4.28 mb) published September 2017 that was reviewed by stakeholders and led to the two proposed design options. 

Needs & Benefits

To relieve chronic traffic congestion and improve mobility along I-5 in the vicinity of Joint Base Lewis-McChord, WSDOT is proposing to rebuild the interchange of Steilacoom-DuPont Road (Exit 119) and adding lanes to I-5. This will support congestion relief on I-5 during peak traffic periods while maintaining access to neighboring communities and JBLM. The proposed build alternative also includes grade separation of the roadway over the railroad.

Why do you have to rebuild the interchange?

  • At the Steilacoom-DuPont Road interchange, the existing 1957 bridge over I-5 has openings that limit the potential to add lanes to the interstate. In addition, the existing overpass does not meet current vertical clearance standards from I-5. A new interchange will be built to current design standards and allow for additional lanes of I-5 in both directions.
  • Current traffic flow is constrained by the close proximity of the ramp intersections, JBLM’s DuPont Gate, the railroad line, and the intersection of Wilmington Drive and Barksdale Avenue.
     

Timeline

  • Determine build alternative: Mid 2016 through 2017. In May 2017, WSDOT reinitiated discussions with stakeholders to define a reconfiguration of the Steilacoom-DuPont Road (Exit 119) interchange that meets the project purpose and need. These efforts have resulted in the linked feasibility report (pdf 4.28 mb).
  • Environmental Studies: 2018 to mid 2019
  • Acquire Right of Way:  Mid 2019 to late summer 2021
  • Design-Build Contract begins for final design and construction: Late 2021
  • Construction complete: 2024
     

Funding

In July 2015, the Washington State Legislature included $495 million to fund the I-5 Mounts Road to Thorne Lane Interchange - Corridor Improvements project, as part of the Connecting Washington transportation package. This project is funded through a 10 year period, from 2015-2025.

Contact

Bill Elliott
WSDOT JBLM Project Manager
360-357-2735

Cara Mitchell
WSDOT Olympic Region Communications
360-357-2703

I-5 Mounts Road to Steilacoom DuPont Road small project map