ITD shares future plans for State Highway 55 and I-84, Karcher Interchange at Nampa open house July 7

The Idaho Transportation Department (ITD) invites the public to an open house this month for two adjacent projects in Canyon County. Design plans will be shared for improvements to the Interstate 84, Karcher Interchange and several miles of State Highway 55 west of the interchange.

Community members may stop by an in-person open house on Thursday, July 7 between 5 and 7 p.m. at Nampa Christian School, 11920 W. Flamingo Avenue in Nampa. Online open houses for each project will also be available July 7-14 at and

“These two projects are part of ITD’s ongoing work to address growth and the resulting congestion on highways in Canyon County, particularly State Highway 55,” said project manager Erika Bowen. “ITD is targeting the most urgent needs in this area while continuing to plan for long-term solutions.”

The I-84, Karcher Interchange project includes widening the interchange bridge and adding a new westbound lane across the interchange to Caldwell Boulevard. Several improvements are also planned on the interchange ramps, signals, and intersections. Details are available at

The SH-55, Farmway Road to Middleton Road project will widen SH-55 to two lanes in each direction in the busy area between Farmway and Middleton roads. More information is on the project website at

Once construction funding has been confirmed, work on the Karcher Interchange could begin as early as 2023, and the widening of SH-55 could start in 2024.

Funding for this design stage of both projects comes from the Leading Idaho Transportation Expansion and Congestion Mitigation Program. The program allows ITD to build critical infrastructure today that would otherwise take many years to build.

A Spanish interpreter will be present at the July 7 open house. Community members can also request written materials in Spanish by calling (208) 334-8002.