The Idaho Transportation Department is widening Interstate 15 to three lanes in each direction to increase capacity and improve safety between the Northgate and Fort Hall interchanges.

I-15 Northgate to Blackfoot Widening

The Idaho Transportation Department is widening Interstate 15 to three lanes in each direction to increase capacity and improve safety between the Northgate and Fort Hall interchanges.


Lane & ramp closures this week!

Intermittent lane and ramp closures will occur on I-15 near the Fort Hall Interchange on Thursday night, Sept. 3. Continue reading for details.

Summer 2026 update!

Check out the summer 2026 update video to learn about what crews have accomplished during this productive summer construction season on I-15! You’ll also learn about upcoming traffic shifts and how to do your part to keep motorcyclists safe on Idaho’s roadways.


I-15 traffic has shifted

Southbound I-15 traffic has moved to the new lanes from the Chubbuck Road Bridge to the Sheepskin Road Bridge. This traffic pattern will allow crews to continue work to widen I-15 to three lanes in each direction between Pocatello and Fort Hall.

Drone photo of I-15 with live traffic north of the Fort Hall Interchange.

Bridge removal is complete

Crews finished removing the abandoned railroad bridge over I-15 near the Fort Hall Interchange in late July. Thanks to good work conditions and other factors, this work was completed in just 10 days!

View the video to see the bridge demolition in action.


Construction on I-15

Crews began work to widen I-15 between the Northgate Parkway and Fort Hall interchanges (exits 73 & 80) in September 2024. Construction is anticipated to be completed in 2027.  

ITD is widening I-15 to three lanes in each direction to improve safety, increase capacity and modernize aging infrastructure.

Drone photo of I-15

Drone photo of the 2 1/2 Mile Road Bridge.

Improvements include:

  • Widening I-15 to three lanes in each direction.
  • Improving bridges, overpasses and interchange structures.
  • Constructing a barrier wall in the median.

What's happening now?

Crews have constructed the new lanes in the median, the median barrier wall and the northbound lanes on I-15. Southbound I-15 traffic is shifted into the new lanes in the median and crews are constructing the new southbound lanes of the interstate. Motorists can expect:

  • Nighttime lane restrictions.
  • Traffic shifts and lane changes.
  • Reduced speed limits.
  • Ramp work and changes at exits 73 and 80. Temporary ramps may be shorter than current ramps.
Map showing I-15 between Pocatello and Blackfoot, with an orange highlight marking the project area between the Northgate Interchange in Pocatello and the Fort Hall Interchange in Fort Hall.

Frequently Asked Questions


Timeline

  • 2022-2024

    Conduct environmental evaluation and develop design plans

  • 2024

    Construction to widen I-15 between Northgate and Fort Hall begins

  • 2025

    Construct the new lanes in the median of I-15 and the median wall

  • 2026

    Construct the new northbound lanes of I-15

  • 2027

    Construct the new southbound lanes of I-15


Stay in touch!

Sign up for email updates.

Sign up for text updates or text 15CONSTRUCTION to 1-866-483-8422.

Call (208) 252-5553

Email info@pocatellotoidahofalls.org

Check Idaho 511 for the latest traffic updates


Downloads & Resources