Construction begins on new Chubbuck Interchange

Construction was to start this week on Idaho’s first diverging diamond interchange.

The diverging diamond interchange, or DDI, will replace an existing interchange at U.S. 91 and Interstate 86 in Chubbuck.

Lane closures on U.S. 91 (Yellowstone Avenue) will be allowed during the evening hours. However, two lanes will be open in each direction on U.S. 91 during peak travel times. In addition, access to businesses on U.S. 91 will be maintained as will access to Interstate 86.

The project is designed to increase capacity and improve safety by reducing congestion and the number of accidents.

A diverging diamond interchange offers significant benefits when compared to a traditional diamond interchange. The largest benefit is continuous left-turning traffic. Because traffic is crossed over to the opposite side of the bridge, there is no waiting for left turns onto the interstate. This eliminates a phase for traffic signals and the potential for crashes with left-turning traffic.

For additional information, please visit the project website. Questions about the project can be sent to

Published 3-8-13