Construction activity picks up on U.S. Highway 20/26 widening

Construction activity is picking up along U.S. Highway 20/26, as the Idaho Transportation Department’s planned improvements to widen the Chinden West corridor continue. This work is part of ITD’s efforts to reduce congestion and crashes on this heavily traveled corridor.

I-84 to Middleton Road

Starting the week of September 12, construction will begin mostly off the highway on the southside of this section of US-20/26. Work includes utility and irrigation construction during daytime hours. As construction progresses, lane reductions are planned, but will be announced well ahead of time. Construction in this section is anticipated to be complete in 2024.

Middleton Road to Star Road

Preliminary design continues on this 6-mile segment of US-20/26. ITD will share updates and host another open house in 2023 for the public to view final design plans. A link to materials shared during the previous May 2022 open house is available at

Star Road to State Highway 16

Drivers should currently plan for overnight lane closures on this portion of US-20/26 starting the week of October 10. The highway will be reduced to one lane in each direction with intermittent delays of up to 15 minutes between the hours of 10 p.m. and 5 a.m. Traffic on Star Road near the highway will also be limited. Flaggers will guide drivers through the work zone. Lane reductions will occur throughout construction as ITD works to widen the highway over the next two years.

Meridian Road to Locust Grove Road

Beginning the week of September 26, crews will start utility work and clearing the ITD right of way in order to widen this section of US-20/26 to two lanes in each direction. This work will continue through December, then paving and road reconstruction is anticipated to start in February 2023 or when temperatures allow. All work will wrap up in early summer.

During construction, one lane in each direction will remain open through the work zone. However, motorists can expect shoulder work, reduced speeds, and periodic lane closures with occasional night work. Specific updates regarding schedule and potential traffic impacts will be provided to residents and businesses in the area when available.

For all work along US-20/26, ITD reminds drivers to slow down, watch for posted signs, and sign up for construction updates by either emailing, calling 208.334.8007, or visiting