• Project

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

Project overview

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 HOV 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.

Project status
Not started
$202 Million

What to expect

A recent traffic and roadway design evaluation of I-5 at Exit 119/Steilacoom-DuPont Road interchange showed that a partial Diverging Diamond Interchange would improve the interchange performance if it were incorporated into the design of the two new bridges over I-5 at Exit 119. The updated design improves safety at the interchange by reducing vehicle conflict points, and improves efficiency with fewer traffic signals. Updated design visualizations are available to view under the maps and drawings tab.

Once construction begins in 2023, travelers will see shifted lanes, overnight lane and ramp closures, reduced speed limit in work zones, and potentially short and long-term ramp closures. 

WSDOT is rebuilding the interchange of Steilacoom-DuPont Road (Exit 119) and adding HOV lanes to I-5 to help improve mobility and and improve travel times during peak commute hours. The project will replace the existing at-grade crossing of the railroad with a grade-separated crossing.  The re-configured interchange will tie-in to Steilacoom-DuPont Road just before Pendleton Avenue.