• Major Project

I-5 - Mounts Road to Thorne Lane I/C - Corridor Improvements

Aerial photo of a congested I-5 through JBLM

Major Project overview

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 revenue package. The project is funded through a 10 year period, from 2015-2025.

Timeline overview

July 2015 to December 2025

Major project status

Construction

Funding

$495 Million

Major project alerts

Construction is currently underway to widen I-5 and rebuild the Berkeley Street and Thorne Lane interchanges.
Contact
Cara Mitchell
WSDOT Communications and Media Relations
Bill Elliott
WSDOT JBLM Project Manager - Planning

In July 2015, the Washington State Legislature included $495 Million for the I-5 Mounts Road to Thorne Lane Interchange - Corridor Improvements project, as part of the Connecting Washington transportation revenue package. The project would widen seven miles of Interstate 5 in Pierce County, from DuPont to Lakewood, adding an HOV lane in each direction. The proposed changes would reduce chronic traffic congestion through the JBLM corridor. To widen I-5, new interchanges are being reconstructed using roundabouts instead of signals to improve traffic flow and reduce the potential for collisions. The new interchanges are grade-separated from the existing rail line, reducing conflicts with trains.

The funding for the project spans over a 10 year period. The funding schedule and right-of-way acquisition play a big part in determining when construction occurs.

Based on the funding schedule, the I-5 Mounts Road to Thorne Ln  I/C Corridor Improvements project is broken up into 4 separate construction projects:

During construction, travelers will see:

  • Reduced speed limit in work zone
  • Overnight ramp and lane closures
  • Shifted lanes
  • Long-term ramp closures and detours