Keeping you moving throughout construction
Construction crews will shift traffic in stages to build the project. Each traffic shift will last for several months. Crews will remove existing infrastructure and build new features.
At the Steilacoom-DuPont Interchange, three travel lanes on both directions of I-5 will remain open. Bike and pedestrian detours will be clearly marked.
Crews will complete Stage 2 of the project in April 2025. In Stage 2, crews shifted northbound I-5 lanes to new pavement and created a work zone between southbound and northbound traffic. Closed sections of northbound I-5 were widened and abutments were constructed for the future Steilacoom-DuPont Road overpass. Work continued at the future roundabout on Steilacoom-DuPont Road and the I-5 bridge over Pendelton Avenue was partially removed. Crews will begin Stage 3 in late March 2025.
New Steilacoom-DuPont Road ramp to northbound I-5
Travelers likely noticed the new on-ramp has a raised concrete island. It created a curve on the ramp to northbound I-5.
The new Steilacoom-DuPont Road ramp to northbound I-5 is a piece of a larger puzzle. The puzzle piece you don’t see yet is the new bridge across all lanes of I-5.
The raised island will serve a future purpose. It will help separate traffic coming from JBLM and DuPont when the new bridge opens.
The new span will open as a diverging diamond interchange in 2026.
So why was this change made now? The raised concrete island was built before the ramp opened to travelers. If crews built it later, the ramp would need a series of closures.
shows how chicane will fit into the overall plan.
Stage 3: March 2025 – early 2026
In late March, crews will shift southbound I-5 lanes towards the median and create new work zones on the shoulder. These temporary lane shifts allow crews room to advance the work on the project. During stage 3, crews will:
- Build the Steilacoom-DuPont Road roundabout.
- Construct the new Steilacoom-DuPont Road overpass.
- Build the roadway between the roundabout and the new Steilacoom-DuPont Road I-5 overpass.
- Activate the traffic signal at Mounts Road.
- Widen northbound I-5 between Clark Road and the future Steilacoom-DuPont Road overpass.
- Partially remove the existing I-5 bridge over Pendleton Avenue.
The first picture below is a rendering of future improvements. The second is an aerial photo showing progress as of February 2025. In Stage 3, crews will construct the roundabout and the road to the new overpass.
New Mounts Road traffic signal
To improve travel time, WSDOT is installing a new traffic signal at the southbound I-5 exit to Mounts Road. The new signal will replace the existing all-way stop.
To prepare for the new signal, crews built a new wall between the Mounts Road exit and southbound I-5. The area creates space for the signal and electrical components. After workers complete this phase, activities will pause until parts for the signal can be manufactured and delivered. The new traffic signal is expected to be operational by late 2025.
What’s next
As the project progresses, we will share updates about upcoming work and milestones, including:
- New roundabout opening in fall 2025, subject to change.
- Removal of the old Steilacoom-DuPont Road overpass in early 2026, subject to change.
- Opening of extended HOV lanes.
Please help keep road workers safe. When approaching a work zone, remember to:
- Slow down – drive the posted speeds for worker and traveler safety.
- Be kind –workers are out there helping to keep people safe and improve the roadways.
- Pay attention – both to workers directing travelers and surrounding traffic.
- Stay calm – expect delays, leave early or take alternate routes if possible; no meeting or appointment is worth risking someone’s life.