System Interchange project enters final year of construction

Photograph showing I-15 southbound lane during construction.

The Idaho Transportation Department’s $112 million rebuild of the System Interchange for Interstate 86 and Interstate 15 at Pocatello is entering its final year of construction with crews working in multiple areas throughout the worksite.

Five bridges were built in the last year, bringing the project total up to eight new structures. Two of the new bridges are steel and measure 414 feet long each. The other three bridges are concrete and measure a total of 387 feet in length. The construction of these bridges included 725 feet of 8-foot diameter concrete shafts installed underground for bridge foundations. In addition, 10,000 feet of steel piles were also driven underground for bridge foundations.

The massive project registered other impressive statistics in 2024:

  • 247,319 cubic yards of dirt moved.
  • 143,500 tons of structural dirt imported.
  • 4,000 cubic yards of concrete poured.
  • 55,894 tons of asphalt placed.
  • 568,862 pounds of metal reinforcement installed.

In the coming year several items will be completed to button up the project.

  • The new southbound-to-westbound ramp will be completed.
  • The old northbound-to-westbound ramp will be removed.
  • The temporary southbound-to-westbound ramp will be removed.
  • The roadway north of the Pocatello Creek on-ramp will be built to its final grade. This will allow movement from Pocatello Creek to Chubbuck and remove the detour currently in place.
  • The new Chubbuck Road underpass roadway will be completed.
  • A chip seal will be applied to extend the life of the new asphalt pavement installed by the project, and the road will be restriped to its final lane configuration.
  • Bridge approaches will be smoothed out to remove bumps made during construction.

Construction is anticipated to be completed in August.

“We appreciate the community’s patience as ITD continues to work with the contractor to button up work items and complete the remaining tasks for this historic project,” Project Manager Greg Roberts said. “ITD is excited to see the travelling public use this updated system interchange for years to come.”

Originally built in the 1960s, the I-86 and I-15 System Interchange is undergoing a rebuild to improve safety and replace aging infrastructure.

Motorists should carefully follow signs and posted speed limits while traveling through the construction area. With crews working day and night at the System Interchange it is especially important that drivers be alert and travel safely.

Motorists are encouraged to use 511.idaho.gov or the 511 app to keep track of project detours. Project details are available on ITD’s projects website at itdprojects.idaho.gov/pages/i-86i-15-system-interchange.

Chubbuck Road Re-opens to Highland Area

Photograph of the new Chubbuck Road underpass.

The long-awaited reopening of Chubbuck Road has come and traffic is once again flowing from Chubbuck to the Highland area. The Idaho Transportation Department opened the road Friday afternoon to through traffic. However, the new underpass will still require a brief closure next summer to open the road up for pedestrian access.

The Chubbuck Road overpass, built in 1962 was an impediment to large loads travelling north and south on Interstate 15. As part of the System Interchange project the decision was made to transform Chubbuck Road into an underpass with additional facilities for pedestrians and bicyclists. That change necessitated a two-year closure for demolition and the construction of two new bridges to carry I-15 over Chubbuck Road.

Now that the new underpass is open to vehicle traffic, residents in Chubbuck wishing to travel to the Portneuf Wellness Complex or Highland High School will no longer be detoured through the Northgate Interchange.

“We really appreciate the public’s patience during this process,” said Project Manager Zak Johnson. “We’re really excited to have Chubbuck Road open to vehicle traffic again.”

While the road is now open for cars there is expected to be a short closure this summer for approximately two weeks so crews can complete the underpass lanes, curbing and sidewalks.

Originally built in the 1960s, the I-86 and I-15 System Interchange is undergoing $112 million of redesign work to improve safety and replace aging infrastructure.

Motorists should follow all signs and posted speed limits while traveling through the construction area. With crews working day and night at the System Interchange it is especially important that drivers be alert and travel safely.

Motorists are encouraged to use 511.idaho.gov or the 511 app to keep track of project detours. Project details are available on ITD’s projects website at itdprojects.idaho.gov/i-86i-15-system-interchange.

Planning is underway to improve the I-15 South Blackfoot Interchange (Exit 89)

Aerial photo of south Blackfoot interchange

The Idaho Transportation Department has begun the planning process to improve the South Blackfoot Interchange at Exit 89. The South Blackfoot Interchange has served motorists since 1961. Since then, eastern Idaho’s population and traffic volumes have greatly increased.

At this interchange, Interstate 15 crosses over U.S. Highway 91 on the Fort Hall Reservation. The interchange is in an area of I-15 that is heavily used for commercial, residential and recreational travel. To improve safety and mobility for motorists, it is necessary for ITD to replace the interchange with a design that has increased capacity and meets current standards.

Project plans currently include:

  • Lengthening ramps to improve safety.
  • Adding a dedicated exit lane to off-ramps to improve ramp operations.
  • Adjusting the interchange to accommodate future additional lanes on I-15.

Improvements to this interchange will be developed and designed based on traffic and other technical data, an environmental evaluation, surveying, and input from the public. The planning, design and environmental evaluation stage of the project is expected to be completed in 2026. Construction of the improvements is anticipated to begin in 2030, depending on the availability of further funding. This project is utilizing both state and federal funding.

ITD will provide multiple opportunities for the public to learn more about the I-15 South Blackfoot Interchange project throughout project development, including a public open house and pop-up meetings in early 2025. For more information visit the project website at itdprojects.idaho.gov/pages/i-15-corridor or call 208-252-5553.

Southbound I-15 traffic being detoured around closed Stoddard Creek bridge

Snowy I-15 southbound roadway with road closure blockade signs and lights in place at Exit 184, Stoddard Creek.

DUBOIS—Southbound travelers on Interstate 15 are being detoured around the Stoddard Creek Bridge at Exit 184, which has been closed due to a damaged and deteriorating road surface. Interstate traffic is being slowed to 45 mph and directed onto the ramps so drivers can proceed over and through without stopping.

The Idaho Transportation Department has closed W. Camas Creek Road under the bridge to allow for this detour. Operations engineers and facilities managers are monitoring the path to ensure smooth passage for vehicles and semis.

Major improvements to the Stoddard Creek Bridge were already planned for early next spring. With the bridge condition worsening substantially, these have been advanced to start in January. Repairs are expected to take several months, with this closure in place until spring.

The Idaho Transportation Department Dubois maintenance crew and other operations personnel are monitoring the closure daily. Traffic control devices are also weighted and placed to avoid being covered by snow removal efforts. ITD will make necessary changes and efforts to keep traffic in this area moving safely through the winter.

Road updates and status can be found at 511.idaho.gov or on the Idaho 511 app.

Pocatello Creek ramp closure scheduled for this week

Drone photo of the System Interchange at Pocatello.

Beginning tomorrow at 7 a.m. the Pocatello Creek Road on-ramp to northbound Interstate 15 will be closed to allow crews to pave the new on-ramp. The closure is expected to last until approximately 5 p.m. Friday. Detours will be in place to guide traffic to the Northgate Interchange or to the Clark Street Exit.

Originally built in the 1960s, the I-86 and I-15 System Interchange is undergoing $112 million of redesign work to improve safety and replace aging infrastructure. The project is scheduled to be completed next summer.

Motorists should carefully follow signs and posted speed limits while traveling through the construction area. With crews working day and night at the System Interchange it is especially important that drivers be alert and proceed safely through the work area.

Motorists are encouraged to use https://511.idaho.gov or the 511 app to keep track of project detours. Project details are available here on ITD’s projects website —https://itdprojects.idaho.gov/pages/i-86i-15-system-interchange

Pocatello Creek ramp closure scheduled for tomorrow

Beginning tomorrow at 9 a.m. the Pocatello Creek Road on-ramp to northbound Interstate 15 will be closed to allow crews to remove pavement and to prepare to pave the new on-ramp. The closure is expected to last until approximately 2 p.m. Detours will be in place to guide traffic to the Northgate Interchange or to the Clark Street Exit.

I-15 Woodville Overpass scheduled for repair Tuesday night

Map showing I-15 detour on US-91 for Woodville construction

Beginning tomorrow night at 10 p.m., the northbound lanes of Interstate 15 will be closed underneath the Woodville Overpass so crews can replace a damaged girder. A detour will be in place until 6 a.m. on Wednesday.

Traffic will be detoured off the interstate at Exit 108 to U.S. Highway-91 and then will return to the interstate at Exit 113.

The girder was damaged in November when a towed excavator travelling on I-15 struck the bridge. Traffic on the overpass has been limited to one lane while ITD prepared for the repair. Work will continue until the end of the month when the overpass will be fully open to two-way traffic.

Motorists are encouraged to visit 511.idaho.gov or use the 511 app to keep track of project detours.

 

Ramp closure scheduled at the System Interchange

Map of system interchange in Pocatello showing detour through Northgate Interchange.

Beginning tomorrow night, the northbound to westbound ramp of the Interstate 86/Interstate 15 System Interchange will be closed to allow for demolition of the old eastbound to northbound bridge. Traffic intending to travel westbound on Interstate 86 from northbound Interstate 15 will be detoured through the Northgate Interchange. Work will continue until Thursday when the ramp reopens at 7:30 a.m.

Originally built in the 1960s, this is the last existing bridge of the System Interchange that will need demolition as part of the $112 million redesign. The project is scheduled to be completed next summer.

Motorists should carefully follow signs and posted speed limits while traveling through the construction area. With crews working day and night, it is especially important that drivers be alert and proceed safely through the work zone.

Motorists are encouraged to use 511.idaho.gov or the 511 app to keep track of project detours. Project details are also available at https://itdprojects.idaho.gov/pages/i-86i-15-system-interchange

System Interchange weekend ramp closure begins tomorrow

Map showing System Interchange detour through Northgate

Beginning tomorrow at noon the eastbound Interstate 86 to southbound Interstate 15 ramp will be closed while crews construct a temporary road to the new eastbound to southbound ramp. Eastbound traffic on I-86 looking to travel south on I-15 will be detoured north through the Northgate Interchange (Exit 73). The closed ramp will reopen late Sunday.

This work will allow the eastbound lanes to be adjusted to the grade of the new ramp. Doing the work this weekend will limit traffic impacts during the peak Labor Day weekend.

Originally built in the 1960s, the I-86 and I-15 System Interchange is undergoing $112 million of redesign work to improve safety and replace aging infrastructure. The project is scheduled to be completed next summer.

Motorists should carefully follow signs and posted speed limits while traveling through the construction area. With crews working day and night at the System Interchange it is especially important that drivers be alert and proceed safely through the work area.

Motorists are encouraged to use https://511.idaho.gov or the 511 app to keep track of project detours. Project details are available here on ITD’s projects website —https://itdprojects.idaho.gov/pages/i-86i-15-system-interchange

Ramp opens at I-86 and I-15 System Interchange

Photo of the new eastbound to northbound ramp

Starting this evening, motorists will encounter new traffic patterns at the Interstate 86 and Interstate 15 System Interchange in Pocatello. The newly constructed I-86 eastbound to I-15 northbound ramp is set to open to traffic tonight. Alongside this change, the rightmost lane of I-86 eastbound will be closed as part of the new traffic configuration.

Drivers should also be aware that the split point for the eastbound-to-northbound and eastbound-to-southbound lanes will be shifted to the west, near the Hiline Bridge.

Originally built in the 1960s, the I-86 and I-15 System Interchange is undergoing $112 million of redesign work to improve safety and replace aging infrastructure. The project is scheduled to be completed next summer.

Motorists are encouraged to stay informed about the latest traffic updates and detours by visiting 511.idaho.gov or using the 511 app. Additional details about the project can be found on ITD’s projects website, https://itdprojects.idaho.gov/pages/i-86i-15-system-interchange.