New funds accelerate key I-15 and US-20 projects in Eastern Idaho

BOISE, Idaho (KIFI) — Several of Eastern Idaho's roads could be getting a significant upgrade, and some sooner than expected, thanks to new funds. Thursday, during its regular meeting, the Idaho Transportation Board approved staff recommendations for improvements to key roadways, including projects on Interstate 15 near Blackfoot and U.S. Highway 20 near Idaho Falls.

These projects, designed to tackle congestion and safety concerns, are moving forward thanks to Transportation Expansion and Congestion Mitigation (TECM) funds made available by House Bill 25, which was passed by the Idaho legislature earlier this year. The legislation provides an additional $20 million a year to the TECM fund over the next three years and will allow the department to invest an extra $1 billion in the Gem State's transportation system.

With this new funding, the following projects have been recommended for further design and construction:

U.S. Highway 20 Improvements

• US-20 west of Idaho Falls: This project will increase capacity by widening the road to two lanes in each direction, starting at Idaho Falls and moving west as funding allows. Widening will increase safety for freight, recreational, and commuter traffic due to limited passing opportunities and lines of sight. Construction is anticipated to start in 2026, two years earlier than planned. 
• US-20 widening from Chester to Ashton: This project is anticipated to expand the existing roadway into a four-lane divided highway. Construction is anticipated to start in 2028. 
• I-15 and US-20 Interchange: This project continues to make progress toward relocating I-15 Exit 119 to US-20 and realigning US-20 through Idaho Falls to address safety and congestion concerns. Funding will allow for the purchase of private property for future construction. 

Interstate 15 Upgrades

• I-15 and US-26 Interchange (Exit 93): The existing interchange will be replaced to accommodate additional lanes on the interstate and to include longer on- and off-ramps for safer merging. Construction is anticipated to start in 2026, five years earlier than planned. 
• I-15 widening from milepost 89 to 93: This project will add capacity by widening the interstate to three lanes in each direction between the US-26 Interchange and the South Blackfoot Interchange. Construction was previously not funded but is now anticipated to start in 2027. 
• I-15 and US-91 South Blackfoot Interchange (Exit 89): The existing interchange will be upgraded to accommodate additional lanes on the interstate and include longer on- and off-ramps for safer merging. Construction is anticipated to start in 2028, three years earlier than planned. 

These projects are now included in the draft Idaho Transportation Investment Program (ITIP). The public will have an opportunity to provide feedback on these and ITD's complete list of planned projects for 2026-2032 during the annual public comment period in July. Following this, the draft ITIP will be presented to the board for final approval in September.

"The board’s action today reflects continued investment targeting congestion and capacity in major corridors that were previously funded by TECM bonds as authorized by the Idaho Legislature," write ITD spokespersons Sky Buffat and Justin Smith. "In East Idaho, TECM funds allowed for the construction at the South St. Anthony Interchange, which was previously unfunded."