I-15, I-86 Interchange project reaches major milestone

POCATELLO, Idaho (ITD Press Release) – As winter sets in the Idaho Transportation Department marks a major milestone for the historic rebuild of the System Interchange in Pocatello, with crews set to shift traffic and open all bridges this weekend.

Beginning tomorrow crews will restripe the new southbound lanes of Interstate 15. Once complete the new southbound lanes will open to traffic. On Sunday crews will also restripe the new northbound lanes of I-15. When this work is complete both northbound and southbound traffic will be on the new mainlines through the project area. This will mean that all the new bridges will be open to traffic. Additionally, the new northbound I-15 to westbound Interstate 86 ramp will also be opened to traffic.

Begun in July of 2022, the project required building eight new bridges while maintaining traffic through the interchange. This necessitated numerous traffic shifts to utilize old and new bridges. With this latest milestone, most of the major traffic shifts will be complete.

However, construction will continue into next summer. A new detour will be put in place for traffic using the Pocatello Creek on-ramp to head west toward Chubbuck. Traffic will be routed through the Northgate Interchange while crews rebuild the old mainline roadway to match the grade of the new road. That work will continue into early spring.

In addition, work will continue on Chubbuck Road which is scheduled to partially open to traffic in late December. Additional work will need to be done next spring to complete the Chubbuck Road segment of the project after the partial opening.

“We’re really excited to finally have all the I-15 traffic moved to the new mainlines,” Project Engineer Greg Roberts said. “We can’t express enough thanks to the community for their patience as we’ve worked through the logistics of such a large project.”

Originally built in the 1960s, the I-86 and I-15 System Interchange is undergoing $112 million of redesign work to improve safety and replace aging infrastructure.

Motorists should carefully follow signs and posted speed limits while traveling through the construction area. With crews working day and night at the System Interchange it is especially important that drivers be alert and travel safely.

Motorists are encouraged to use 511.idaho.gov or the 511 app to keep track of project detours. Project details are available on ITD’s projects website at itdprojects.idaho.gov/i-86i-15-system-interchange.