Multiyear construction begins next week to widen I-15 between the Northgate and Fort Hall interchanges

Photograph of I-15 and the Northgate 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:

Traffic patterns change at System Interchange

aerial view of I-86/I-15 system interchange

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

ITD asks motorists to consider alternate routes at Blackfoot

Aerial view of Blackfoot Exit 89 Interchange.

With construction ramping up along Interstate 15 the Idaho Transportation Department (ITD) is asking motorists to drive defensively and take alternate routes when possible. Work occurring at the south Blackfoot exit (Exit 89) and north of Exit 93 has resulted in increased congestion along the corridor.

“We recommend Blackfoot residents take an alternate route such as U.S. Highway 91 to an exit north of the Rose area,” Engineer Kevin Sonico said. Doing so not only decreases the number of vehicles on I-15, but also allows motorists to avoid driving through the construction zone north of Blackfoot.

The repaving project north of Blackfoot will improve safety and drivers’ experience with a smooth new surface. During construction traffic is shifted to the southbound lanes through a crossover. Drivers should expect reduced speeds through the construction zone. The project is expected to take about seven weeks to complete.

Work at Exit 89 consists of rehabilitating the bridge surface by repairing joints and potholes. This will extend the life of the bridge. “Our goal is to have this done by September 1,” said Engineer Zak Johnson. “We really want to have everything done before the start of the fair.”

Johnson also recommends drivers take US-91 as an alternate route whenever possible.

Motorists are encouraged to stay updated on project detours and traffic impacts at https://511.idaho.gov or on the 511 app.

System Interchange nighttime ramp closures begins at Pocatello

Beginning tomorrow evening the north-to-west ramp of the System Interchange at Pocatello will be periodically closed to allow for girder placement for a new bridge.

Girders are horizontal steel beams designed to support the bridge deck. As the beams are placed over the northbound to westbound ramp it is necessary to close the roadway beneath for the safety of the travelling public.

Closures are scheduled for:

  • Wednesday from 9:00 p.m. until 1:00 a.m.
  • Friday from 8:00 p.m. until 6:00 a.m.
  • Monday July 22 from 8:00 p.m. until 6:00 a.m.
  • Wednesday July 24 from 8:00 p.m. until 6:00 a.m.
  • Thursday July 25 from 8:00 p.m. until 6:00 a.m.

Traffic traveling north on I-15 wishing to proceed west on I-86 toward Chubbuck will be detoured through the Northgate Interchange.

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.

While this work continues, weather is a major factor for the timing of closures. 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

 

Work begins to resurface I-15 north of Blackfoot

A photo of I-15 with a semi and car.

On Monday the Idaho Transportation Department will begin work to repave the northbound lanes of Interstate 15 from the West Blackfoot Interchange Exit 93 to Riverside Canal near the Rose Road Interchange Exit 98. This project will improve safety and the drivers’ experience with a smooth new surface.

During construction traffic will be shifted to the southbound lanes through a crossover. Drivers should expect reduced speeds through the construction zone. The project is expected to take 50 days to complete.

Throughout the course of the project, crews will be milling down the base layer of the highway to fully reconstruct the road base and driving surface. Work includes pulverizing the existing asphalt, excavating and placing new material as a base, and then paving over the top of the new base.

Travelers are encouraged to use the Idaho 511 system for updated traffic impacts through the construction season.

Nighttime detour planned for I-15/I-86 System Interchange this week

POCATELLO – Beginning tonight and continuing through Wednesday morning, nighttime closures will be in place for a section of Interstate 15 and Interstate 86 at the System Interchange allowing crews to safely place girders for one of the new bridges.

The I-86 eastbound to I-15 northbound ramp will be closed from 8 p.m. to 6 a.m. Monday and Tuesday nights. Drivers looking to head north on I-15 from I-86 will be detoured through the Pocatello Creek Interchange.

Ongoing construction at the System Interchange will improve safety and mobility while replacing bridges built in the 1960s. Work is expected to be complete in 2025.

Motorists should exercise caution while travelling through the construction zone. Those wishing to receive email updates about the System Interchange project can sign up at https://lp.constantcontactpages.com/su/g9MMkN9.

Drivers can also use the 511 app for the latest traffic conditions on all state roadways.

Construction continues on I-15 at Inkom

The Idaho Transportation Department is continuing work on the Interstate roadway and bridges from the south Inkom interchange to the Portneuf interchange. Ongoing work includes guardrail repair, paving, and patching and repairing bridge decks. In addition, crews are patching pier caps, applying epoxy overlays, and waterproofing parapets on the Rapid Creek, South Inkom interchange, and Portneuf River bridges.

Work is anticipated to continue through the end of June with single lane crossovers. Drivers are reminded to slow down in work zones, allow other vehicles to merge, and drive defensively.

Replacement of the West Inkom interchange, Union Pacific Railroad, and Main Street bridges are still planned for next year.

Nighttime detour planned for I-15/I-86 System Interchange this week

Beginning Wednesday evening and continuing through Friday morning, nighttime closures will be in place for a section of Interstate 15 and Interstate 86 at the System Interchange to allow crews to safely place girders for one of the new I-86 eastbound to I-15 northbound bridges.

The I-15 northbound to I-86 westbound ramp will be closed from 9 p.m. to 5 a.m. Wednesday and Thursday nights. Drivers looking to head west on I-86 from I-15 will be detoured to the Northgate Interchange.

Ongoing construction at the System Interchange will improve safety and mobility while replacing bridges built in the 1960s. Work is expected to be complete in 2025.

Motorists should exercise caution while travelling through the construction zone. Those wishing to receive email updates about the System Interchange project can sign up at https://lp.constantcontactpages.com/su/g9MMkN9.

Drivers can also check or download the 511 app for the last traffic conditions on all state highways and freeways.

Construction at System Interchange halfway complete

Map showing new bridge locations.

The historic rebuild of the System Interchange in Pocatello is nearing the halfway point, and motorists will continue to see progress in the coming year.

Major milestones for the upcoming season include building five new bridges and demolishing one bridge. Bridges will be constructed to carry southbound traffic on Interstate 15, traffic over Chubbuck Road and traffic heading east on Interstate 86 to access northbound I-15.

As crews come back from the holidays, next up for the project will be drilling concrete shafts for the foundations of the new southbound bridges on I-15. Each shaft will be 8 feet in diameter and drilled up to 60 feet deep to support the weight of I-15 passing overhead. Motorists will also notice construction of retaining walls for the new ramp from I-86 eastbound to I-15 northbound.

This winter crews will be in multiple locations throughout the worksite. Motorists are reminded to follow posted speed limits and watch for work vehicles entering and leaving the interstate at any time day or night.

Originally built in the 1960s, the interchange is undergoing a $112 million redesign to improve safety and replace aging infrastructure. These safety improvements include:

  • Redesigning ramps to have drivers trying to head northbound on I-15 from I-86 merge from the right, rather than the left.
  • Traffic from Pocatello Creek Road will no longer have to cross three lanes to head to Chubbuck. Instead drivers will travel under the northbound and southbound lanes of I-15.
  • Chubbuck Road will be transformed from an overpass into underpass. This means oversized vehicles will no longer have to detour off the interstate. Those who walk and bike will also be better able to travel from Chubbuck to the Portneuf Wellness Complex on the east side of the interstate.

Construction is slated for completion in 2025. Those wishing to learn more about the project can visit the website at https://itdprojects.idaho.gov/pages/i-86i-15-system-interchange.