Contact Us

Work on I-86/I-15 interchange project to start this summer

By Idaho State Journal Staff, Feb 17, 2022

The Idaho Transportation Board has voted to expedite a planned $115.5 million overhaul of the interchange between Interstate 86 and Interstate 15, serving Pocatello and Chubbuck.

It was one of four major statewide projects the Idaho Transportation Board selected during its Feb. 17 meeting in Boise to be accelerated, with work starting this summer. The I-15/I-86 interchange project involves road, ramp and bridge upgrades at the junction of the interstates, as well as construction of a separate bicycle and pedestrian path.

This overhead map shows the locations of new lanes and ramps, pictured in blue, planned as part of an overhaul of the
interchange between Interstate 86 and Interstate 15.

The work will be covered by sales tax revenue and financed with state bonds available through the Transportation Expansion and Mitigation Fund, which was created in 2017.

“Idaho is the fastest growing state in the nation. To keep up with the demands of growth, these funds will help save Idahoans’ time, keep us safe on our roads, and makes our state’s economy even stronger,” Gov. Brad Little said in a press release. “I appreciate the work of the Idaho Transportation Board, the department and the Legislature for acting quickly to put this money to work with projects that will benefit the state.”

An Idaho Transportation Department spokesperson said the I-15/I-86 interchange project is expected to be completed between late 2024 and early 2025.

The project should make it much easier for motorists accessing I-15 via Pocatello Creek Road to merge with traffic and exit onto I-86, without having to cross several busy lanes within a short distance. According to ITD’s description of the project, between the Pocatello Creek and Northgate interchanges of I-15, new northbound lanes will be built west of their existing locations, within what is now the highway median. The ramp connecting I-15 northbound to I-86 westbound will be redesigned to exit from the right-hand side rather than the left-hand side, avoiding the need to cross lanes. The ramp connecting I-86 eastbound to I-15 northbound will be redesigned to merge on the right-hand side of northbound I-15 lanes, rather than the left-hand side. Chubbuck Road will be lowered and made into an underpass beneath I-15, and a pair of new bridges will be constructed over Chubbuck Road. A new connector ramp will merge traffic entering northbound I-15 from the Pocatello Creek interchange after the I-86 westbound ramp.

The Portneuf Greenway Foundation will coordinate with ITD to build the pedestrian and bicycle pathway, linking Pocatello Creek Road to the Portneuf Wellness Complex.

ITD plans to advertise the project for bids this month. According to ITD’s tentative schedule, the I-15 northbound ramp to the I-86 westbound ramp will be closed for up to four weeks starting in the late spring or summer, with traffic detoured to the Northgate interchange.

Chubbuck Road across I-15 will be closed for the duration of construction, with traffic detoured onto New Day Parkway and Northgate Parkway.

Spanning the summer of 2022 through the fall of 2023, a new I-15 northbound alignment and new interchange ramps will be built. I-15 northbound and southbound traffic will remain open on existing alignments, with possible short-term lane closures.