Construction is underway to widen I-84 between South Jerome and Twin Falls interchanges

JEROME – As part of Governor Brad Little’s Leading Idaho Transportation initiative, the Idaho Transportation Department (ITD) has begun a project to widen I-84 between the South Jerome Interchange (Exit 168) and the Twin Falls Interchange (Exit 173). Construction begins this week on this 2.5-year project.

I-84 serves as a primary interstate route, and traffic counts are expected to increase substantially over the next 20 years. The existing interstate will not be able to accommodate anticipated future traffic volumes. These improvements will increase capacity and improve safety on I-84 to serve South-central Idaho for years to come.

In 2023, motorists should expect:

  • I-84 will be restricted to one lane in each direction at night. Occasional daytime lane restrictions may be necessary.
    • Rolling closures on I-84 will occur this spring/summer for blasting rock in the median.
  • Traffic shifts will be used throughout construction.
  • The speed limit on I-84 will be reduced.
  • 400 South Road will be closed intermittently.

Funding for this project comes from the Leading Idaho TECM Program. The program allows ITD to address rapid growth and build critical infrastructure today that would otherwise take many years to fund and build. Concrete Placing Company is the contractor for this $92.9 million project.

Construction is anticipated to be completed in late fall of 2025. Those who are interested in learning more about the project are invited to visit the project website at or call (208) 391-3735.

Information in Spanish can be found on the project website or by calling (208) 398-3696.