New I-86 bridge opens at Chubbuck

A new three-lane Interstate 86 bridge at Chubbuck is now open as construction crews head into Thanksgiving week. The new bridge over the Union Pacific Railroad adds capacity, improves traffic flow, and is designed to last 80 years.

While the bridge is complete and open, work continues nearby with the installation of a new sound wall. In addition, paneling will be installed on the bridge to protect the railroad tracks from any debris falling off the bridge.

Crews will continue to work on the I-86/I-15 System Interchange through the winter months. The next major milestone is opening the new I-15 mainline roadway slated for mid-December. Following that contractors will begin demolition of the old I-15 bridges.

This week crews will work until noon Wednesday and return to the construction site on Monday. Still, it is important that drivers be safe while travelling through the System Interchange, particularly with increased holiday traffic.

“Please pay attention to construction signs, be courteous, follow posted speed limits, and drive safe so everyone can go home safely, including workers on the project,” Engineering Manager Aaron Baird said.

ITD to host open house to solicit feedback on 2026 US-91 widening

intersection of US 91 & Siphon Road

The Idaho Transportation Department (ITD) will hold an open house on Thursday, Nov. 2 from 4 to 7 p.m. to present preliminary plans for improvements along U.S. Highway 91 (Yellowstone Highway) between Park Lawn Drive and Siphon Road.

“This is an important project for the Chubbuck area,” Project Manager Kevin Sonico said. “These improvements will address the traffic growth in the area and make it safer for both drivers and pedestrians. We encourage everyone to stop by Chubbuck City Hall any time from 4 to7 p.m. on Thursday to learn more about the project. We’ll be ready to answer questions and collect comments.”

Plans include widening US-91 from three lanes to five lanes from Park Lawn Drive to Siphon Road. The project will also install a new signal and pedestrian facilities at the Siphon Road intersection. Lighting, curb, gutter, sidewalks and a shared-use path along the east side of US-91 will be constructed. In addition, the Chester Drain will be piped.

For those who cannot attend the public meeting on November 2, ITD will post meeting displays the following day on the project website for review through Nov. 16. If you have questions about the project, or would like to submit feedback, you can contact the project’s public involvement manager, Andrea Gumm, at or 208-870-8751.

SH-36 closed due to mud slides

POCATELLO – At approximately 6:30 pm on Tuesday a mud slide necessitated the closure of SH-36 between Ovid and Preston. Continued warming temperatures resulted in two more slides in the area. As of 2:30 pm Wednesday the highway remains closed north of Mink Creek.

ITD crews are working to clear ditch and culverts to help the spring runoff waters move away from the highway. However, the safety of the travelling public is the primary concern and the road will remain closed until engineers are confident the roadway is safe.

To travel between Preston and Montpelier motorists can detour via SH-34 and US-30.

As Idaho enters the late spring, this winter’s heavy precipitation in the Franklin, Caribou, and Bear Lake Counties presents a significant chance of flooding. Motorists need to be aware of local conditions and not drive through water running over the roadways.

To get the latest updates on road conditions and closures, please check or download the 511 app.

A backhoe works to remove mud from the roadway ITD Employee overlooks a washed-out hillside

Weather delays planned lane closures at System Interchange


POCATELLO – The recent snowstorm has delayed delivery of girders for the new I-15 bridge at the System Interchange in Pocatello. ITD planned to install the girders this weekend, but they could not be safely delivered to Pocatello in time. This means the planned lane closures for this weekend will also be delayed until all of the girders can be safely delivered to Pocatello. When that occurs, ITD will update the public.

To protect Idaho’s workers and other motorists, ITD asks those travelling on Idaho’s highways to follow work zone speed limits, be patient, and plan for extra time to travel to their destinations.

To learn more about the final design of the System Interchange citizens can watch this video:

ITD System Interchange Construction Accelerates


POCATELLO – With the arrival of spring the Idaho Transportation Department is ramping-up construction at the System Interchange in Pocatello. As part of Governor Little’s “Leading Idaho” initiative, the System Interchange is being redesigned to replace aging bridges built in the 1960s and improve traffic safety.

While work at the interchange continued throughout the winter, in the coming week ITD’s contractor will be placing girders for the new I-15 northbound bridge. This will necessitate rolling slowdowns, delays, and short detours around the I-86 to I-15 ramp leading from Chubbuck toward Blackfoot.

Additionally, as work progresses into the first week of April the Chubbuck Road bridge will be demolished. This will be done in stages with traffic detoured through Chubbuck at night. The first closure will be for northbound traffic and the second for southbound I-15 traffic.

Other projects will also see ramped-up operations including the Fort Hall Interchange and bridge work on I-86. With unprecedented funding made available for construction, Idaho motorists will continue to see increased activity on Idaho’s highways.

To protect Idaho’s workers and other motorists, ITD asks those travelling on Idaho’s highways to follow work zone speed limits, be patient, and plan for extra time to travel to their destinations.

To learn more about the final design of the System Interchange citizens can watch this video

ITD crews fixing potholes in East Idaho

EAST IDAHO – The Idaho Transportation Department is working to address potholes created by rapidly changing temperatures this winter. Recent snows followed by warm temperatures allows water to enter through cracks in asphalt. When that water freezes at night it can result in potholes forming on the surface of Idaho’s highways and freeways.

While winter maintenance typically focuses on keeping roads clear of snow, crews are also repairing potholes on I-15, within the city of Idaho Falls, as well as in other areas of the region.

D5 operations engineer Greydon Wright says, “The biggest area that we have been fighting them are on I-15 between Exit 93 (Blackfoot) and the Blackfoot Rest Areas.”

Similarly, D6 operations engineer Bryan Young reports they have been hard at work as well, “This week we have received numerous comments about the potholes in Idaho Falls. The Idaho Falls Maintenance Shed has successfully repaired the major potholes and will continue to repair the roadways as more potholes appear.” However, Young points out that repairs are weather dependent. So, drivers must still pay attention to avoid hitting a rough piece of pavement.

Patching during the winter consists of using a “cold patch” that is intended to be a temporary solution. Crews will return in the summer to perform more permanent repairs as needed. In addition, ITD has several projects scheduled this year to address older pavement throughout the region.

Pile driving to begin Thursday at Pocatello

Road Work Ahead sign

Blue and white circular logo for "Leading Idaho" projects sponsored by Governor Little

POCATELLO – Beginning Thursday morning work crews at the System Interchange will begin pile driving piers for new bridges. As part of Governor Little’s Leading Idaho initiative, the project was fast-tracked partly due to the aging 1960s bridges due for replacement. The new piers will create a stable foundation to protect the structure of the new bridges.

Pile driving uses a hydraulic hammer that forces piers downward through the soil. Unavoidably, the operation creates noise as the hammer falls on the pier. Work for this portion of the project will be conducted during the daytime. However, in the next week or two additional pile driving will be required at Chubbuck Road that will include some nighttime work.

Motorists should carefully follow signs and posted speed limits while travelling through the construction area. With crews working day and night and with the onset of winter it is especially important that drivers be alert and proceed safely through the work area. Drivers are encouraged to check or the 511 app to keep track of road conditions and construction. Project details are available on ITD’s projects website —

Citizens who wish to receive updates via email can subscribe at this link:

This project is partially funded with Transportation Expansion and Congestion Mitigation (TECM) funds as part of Governor Little’s Leading Idaho initiative. The program allows ITD to accelerate project timelines to address rapid growth and build critical infrastructure today that would otherwise take many years to fund and build.

Construction crew driving piles with heavy equipment
Pile driving utilizes a hydraulic hammer to place the piles deep below the surface of the ground.

I-86 to I-15 detour scheduled for tonight

POCATELLO – Beginning this evening at approximately 8:00 p.m. paint crews will be restriping the ramp from I-86 to I-15 southbound. Work will continue through the night and will end at approximately 6:00 am tomorrow. During the restriping work the ramp will be closed and southbound traffic will be detoured through the Northgate Interchange. While it is hoped the work will be completed in one night, there is a possibility the detour will also be used Thursday night to finish striping.

Motorists should carefully follow road signs, obey work zone speed limits, and share the road with other vehicles navigating detours.

Those interested in receiving regular updates on the project can visit the project website at and sign-up for email updates.

I-86/I-15 October Detour


Fires burning along I-15 at Pocatello and at Malad Summit

Fire at Malad Summit

POCATELLO – Multiple fires are burning along I-15 at Pocatello. There is also a fire at Malad Summit on I-15. Fire crews are actively working in the areas, but traffic is delayed or blocked. Motorists are encouraged to slow down, watch for and move over for emergency vehicles and check or the ITD 511 app to receive road status updates. The causes of the fires are not yet known.

Drivers should take extra care while driving through Idaho this weekend with fire danger high amid unseasonably warm temperatures. In particular, motorists should:

  • Ensure tow chains on trailers are not dragging which can cause sparks.
  • Tires on vehicles and trailers are in good condition for highway driving. A blown tire can cause the wheel rim to kick sparks into dry grass.
  • Never throw cigarettes or other combustible materials out of a vehicle.
  • Never throw glass or other litter out of a vehicle. Glass bottles and other objects can reflect or focus the sun’s rays causing ignition.
  • Do not park your vehicle over dry grasses when you pull off a road. The exhaust and other hot portions of the undercarriage can ignite a fire.
Fire crews responding to one of the fires along I-15
A burned area near the southbound lane of I-15
Pocatello Fire Department and other agencies quickly responded to the fires.

Historic rebuild of System Interchange at Pocatello begins

Looking at system interchange from the west

POCATELLO – Preliminary work on the Idaho Transportation Department’s project to rebuild the I-86/I-15 System Interchange is beginning this week. Originally built sixty years ago, the design needs to be updated to handle greater traffic volumes and to replace aging bridges that are reaching the end of their life. Joint venture contractors Sundt-Cannon is expected to begin moving equipment into the project area before the end of the week.

The scale of the endeavor is truly historic and took years to bring to fruition. When completed, approximately 900,000 cubic yards of excavation will be completed. In addition, about 225,000 tons of base material will be brought in; 111,000 tons of asphalt will be placed; and over 6,500 cubic yards of concreate will be poured. 70,000 square feet of retaining walls will also be built throughout the project area. Finally, ITD will build eight new bridges. Four of those will use precast concrete girders and four will have steel girders. In all, nearly 5,000,000 pounds of steel will be used in the bridges. Crews will work year-round for approximately three years to complete the project.

The two most significant changes motorists will see during construction are a detour for traffic travelling from I-15 northbound to I-86 westbound and the closure of the Chubbuck Road overpass.

In early August, northbound traffic from I-15 exiting west toward Chubbuck will be detoured through the Northgate Interchange and back onto I-15 South to then proceed to I-86 West. To maintain traffic for the anticipated 2-year construction of the project, the ramp will need to be lowered prior to beginning bridge construction. This necessitates the ramp closure and detour through the Northgate Interchange. This work should be completed by early September.

The Chubbuck Road overpass will be closed around August 1st, prior to the beginning of the school year, and will remain closed during the duration of the project. Construction will remove the existing bridge, excavate new embankments, and create bridges for I-15 to pass over Chubbuck Road. The final Chubbuck Road design will be easier and safer to navigate for motorists, bicyclist, and pedestrians. During construction motorists will be detoured through the Northgate interchange.

Westbound traffic detour map
During the first phase of construction traffic from northbound I-15 intending to travel west will be detoured through the Northgate interchange.

While demolition of the Chubbuck Road overpass will not begin immediately, an important concern for the school district and other interested parties was altering bus routes and student driving routes after the beginning of the school year. This could cause unnecessary delays and confusion for buses, faculty, parents, and students.

“The school district had some real concerns about making a change during the school year and we are doing what we can to accommodate them for the safety of the students and smooth operation of the schools,” said project co-manager Zak Johnson.

The $112 million project to rebuild the system interchange is a massive undertaking that requires extensive coordination with many different parties. ITD has been in close contact with city leaders, ISP, the Bannock County Sheriff’s office, emergency response, schools, regional transit, and others to ensure the safety of Idaho citizens and motorists passing through Southeast Idaho.

An important question some in the community express is, why now?

“The aging bridges will continue to get closer and closer to the end of their design lifespan,” said project co-manager Greg Roberts, “They would still be functional, but weight limits would start to have to be imposed on truck traffic. That would negatively impact Pocatello’s economic future.”

That is an important concern for Idaho businesses. Large loads, called “mega-loads”, travel through the Gate City to Montana and west to other regions of Southern Idaho. Local manufacturing companies need to be able to move their products to their customers quickly and safely.

However, it is not just the age of the 1960’s bridges that is a concern. When the System Interchange was built there was almost no development on the east side of I-15. Today the Highland area has subdivisions, a high school, the fairgrounds, and the Wellness Complex. In addition, development at Northgate has begun and will result in even more traffic.

“We can only expect traffic volume to increase and with it congestion,” said Roberts. “That will cause the ‘weave’ between the Pocatello Creek onramp and the Chubbuck exit to get worse. Traffic entering, I-15 intending to head toward Chubbuck already has difficulty during peak times crossing all the way to the left to head west on I-86.”

The issue for drivers now is finding a gap to slip into so they can head west toward Chubbuck.

“That will only get worse if we do nothing,” added Johnson, “Gaps between cars will become smaller and smaller making it more difficult to safely merge. Drivers will be forced to make more aggressive lane changes to head to Chubbuck. That kind of situation increases collisions. We don’t want to wait until things become dangerous and people get hurt.”

Safety is a primary concern for project managers and the contractors as motorists prepare to drive through the work site. “These are our neighbors and family working out there,” said Roberts. “We do everything we can to make the worksite safe, but it’s really important that drivers follow posted speed limits, watch for lane changes and signs, and give other motorists space on the road.”

Diagram of Chubbuck Road detour
The Chubbuck Road detour will take motorists through the Northgate Interchange.

Both Roberts and Johnson have seen severe worksite accidents caused by inattentive drivers. In one instance a motorist followed a work truck directly into the work site. Unfortunately, deaths do occur and it is often the result of a motorist that do not take care in a work zone.

“It’s something that never leaves you,” said Johnson as he reflected on a fatality on a previous project. “We do everything we can to keep people safe, but when it happens it’s hard not to take it personally. We just ask everyone to please keep themselves, their families, and their neighbors safe while this project is being completed.”

Once completed, the new System Interchange will be safer and ready to carry the increased traffic volumes for the fastest growing state in America.

This project is partially funded with Transportation Expansion and Congestion Mitigation (TECM) funds as part of Governor Little’s Leading Idaho initiative. The program allows ITD to accelerate project timelines to address rapid growth and build critical infrastructure today that would otherwise take many years to fund and build.

This video describes how the new interchange will work and improve mobility and safety for the public –

Project details are available here on ITD’s projects website —


Overhead view of new Chubbuck Road underpass
The new design changes Chubbuck Road into an underpass with additional space for pedestrians and bicycle lanes.
Overhead view of interchange
Vehicles travelling northbound from Pocatello Creek Road will merge with I-86 traffic on a new ramp. Both lanes will then meet with I-15 northbound traffic near Chubbuck Road.


Overhead view of interchange
When completed, westbound traffic from Pocatello Creek Road will pass under I-15 to merge with I-86.