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.
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.
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.
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.
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
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
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.
The Idaho Transportation Department (ITD) is beginning construction to widen Interstate 15 (I-15) to three lanes in each direction between the Northgate and Fort Hall interchanges to accommodate projected increases in traffic volumes. This Leading Idaho multi-year project includes widening I-15, constructing a median barrier to separate opposing lanes of traffic and reconstructing bridge structures, including overpasses and underpasses, to accommodate the additional lanes.
Motorists can expect to see traffic control devices in the project area as early as Monday morning. Work has been phased to maintain two lanes of traffic in each direction during the day for most of the project. However, motorists should be aware some nighttime work will require single-lane closures.
This fall, crews will shift traffic to create the space they need to build a median wall, reconstruct structures, and demolish and reconstruct the existing northbound lanes of the interstate.
During construction, motorists should expect:
- Nighttime work begins the week of August 19 and will continue for the first couple weeks of construction. Work will occur from 7 p.m. to 6 a.m. Nighttime single-lane closures may happen occasionally after this period.
- Daytime work is expected to begin early this fall and will occur between the hours of 7 a.m. and 6 p.m.
- Lane restrictions will occur on I-15. Most work requiring lane restrictions is anticipated to occur at night.
- Ramp adjustments will occur at the Fort Hall Interchange (Exit 80) to match the grade of the new mainline.
- Variable speed limit signs will be installed in the project area, allowing ITD to lower speeds when crews are working near traffic.
Construction is anticipated to be completed in 2027. The project will increase capacity and improve safety on I-15 to serve East Idaho’s growing transportation volumes for years to come.
Due to the large project area, the widening of this stretch of I-15 has been divided into two projects with separate contractors. These contractors will work simultaneously to complete the projects. Western Construction, Inc. and Sundt Construction are the contractors for the north and south project areas, respectively.
Construction is being funded as part of Idaho Governor Brad Little’s Leading Idaho transportation funding initiative. The Leading Idaho initiative allows ITD to take a deliberate approach to advance large projects that will enhance safety, improve mobility, further strengthen Idaho’s economy, and positively impact communities across the state for years to come.
To sign up for project updates:
Beginning this morning, traffic patterns are changing at the System Interchange in Pocatello. Traffic using the southbound entrance ramp from Northgate can now merge with the new southbound alignment and will no longer be detoured through the Interstate 86 Chubbuck Exit before returning to Interstate 15.
In addition, southbound I-15 traffic wishing to travel west on I-86 will now drive over the new Chubbuck bridge before exiting to the right.
Motorists are encouraged to keep up-to-date via 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
