System Interchange Construction in Full Swing

POCATELLO – The Idaho Transportation Department’s rebuild of the System Interchange for I-86 and I-15 at Pocatello is in full swing with crews working multiple areas throughout the worksite. As part of Governor Little’s Leading Idaho initiative, the project is quickly changing how the heart of the Interstate in Pocatello appears.

The lowering of the ramp for westbound traffic from northbound I-15 to I-86 is now complete and work on building the new bridges is beginning. Temporary barriers are in place at multiple locations and motorists will also notice changes in lane striping as traffic is shifted away from work areas.

View of construction site at System Interchange looking south with large crane in center — Cranes are being placed to begin drilling shafts for bridge piers.

One safety innovation being implemented is the use of a conveyor belt system to move earth fill from one area of the project to another. The conveyor allows crews to move material without using trucks entering and exiting the Interstate. That makes for a safer work zone for drivers and work crews. It is important that public keep clear of the conveyor system for their own safety.

In the coming weeks cranes will appear on the project and begin drilling shafts for new bridge piers. Excavators and other earthmoving equipment are also working in multiple areas to reprofile the land. Throughout the work zone water trucks are being utilized to keep dust down. Inspectors and engineers are also on-site daily ensuring safety and compliance with designs.

Near the end of the month or early next month pile driving will begin in the northern portion of the work area. There will be some associated noise during this portion of the operation.

Speed limits in the work area are now set at 55mph and should always be carefully observed, day and night. Crews are working long hours including some night work. Drivers should also know that lane configurations are changing and should be prepared to adjust to the difference by watching for signs and following pavement markings.

It is especially important with such a large project that motorists plan for extra time and to be patient with other drivers by allowing them to merge and change lanes as needed. Sharing the road and watching for workers and construction vehicles entering the Interstate is essential to keeping everyone safe.

The historic rebuild of the I-86/I-15 System Interchange was the outgrowth of a need to replace aging bridges and improve safety. The bridges, built in the 1960s, are currently safe but needed to be replaced due to their age. Failure to do so would result in a need to place restrictive load limits which would hinder commerce.

Water truck spraying dusty ground to control dust — Water trucks are working tirelessly to keep dust from construction to a minimum.

ITD also noted an increase in aggressive lane changes and congestion within the interchange, particularly just north of the Pocatello Creek exit. The rapid motion of entering I-15 at Pocatello Creek and crossing to the passing lane to exit toward Chubbuck did not exist when the interchange was built. However, with population growth and associated development that traffic is now significant. Such “exit left” and “enter left” movements do not meet driver expectations, cause confusion, and results in frustration for drivers.

Another much-needed improvement was a redesign of the Chubbuck Road crossing. The old 1962 bridge is narrow and has limited capacity for pedestrians and bicyclists. With the growth of Pocatello and the addition of the Portneuf Wellness Complex a significant change was needed. ITD’s new design changes Chubbuck Road from being an overpass over I-15 to an underpass beneath the freeway with dedicated bike lanes and wider sidewalks. Removal of the bridge also creates more space for the larger project to handle increased traffic.

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 video describes how the new interchange will work and improve mobility and safety for the public – https://youtu.be/KRdVBAyXweA

Project details and updates are available here on ITD’s projects website https://itdprojects.org/projects/i-86-i-15-system-interchange/

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.

View of earthmoving equipment looking south near Pocatello Creek Exit — Earthmoving equipment is working throughout the System Interchange project site

View of concrete rail on Chubbuck Road showing the date 1962 — The age of the 1960s era bridges necessitated their replacement.

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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 https://itdprojects.org/i-86-i-15-system-interchange and sign-up for email updates.

I-15/I-86 Detour at Pocatello Ends

POCATELLO – The northwest ramp from I-15 to I-86 reopened this morning at the System Interchange in Pocatello. Traffic heading from I-15 toward Chubbuck and American Falls is no longer detoured through the Northgate Interchange. The detour was needed to lower the ramp so new bridges can be built for I-15 through the System Interchange.

Motorists should carefully follow signs and posted speed limits while travelling through the construction area. With crews working day and night it is especially important that drivers be alert and proceed safely through the work area. Drivers are encouraged to check https://511.idaho.gov or the 511 app to keep track of road conditions and construction. Project details are available on ITD’s projects website — https://itdprojects.org/projects/i-86-i-15-system-interchange/

I-86 Bridge Repair Work Begins in Power County

AMERICAN FALLS – The Idaho Transportation Department began repairs on two I-86 bridges in Power County this week. The Sunbeam Road and Seagull Bay bridges will both be receiving new roadway surfaces to protect the integrity of the bridges and improve safety. The first phase of the project will progress for one month while the eastbound bridges are resurfaced. The second phase will also last one month as the westbound bridges are similarly repaired. All work is scheduled to be completed by the end of October.

During construction traffic will be moved to one side of the Interstate prior to the bridges and some exiting traffic will be detoured. After the construction area is passed, traffic will cross back over to the regular side of the Interstate to proceed as usual. Motorists should watch closely for signs indicating lane changes, detours, and speed limit reductions.

During the current first phase, eastbound traffic is being crossed over to the westbound side of the Interstate prior to Sunbeam Road at American Falls. Traffic remains two-way on the westbound side of the Interstate until past Seagull Bay Exit 44. Therefore, eastbound Interstate traffic will not be able to use Exit 40 into American Falls and Exit 44 to Seagull Bay. Motorists should instead exit at the west American Falls / Rockland Exit 36 or the Rainbow Road Exit 49.

American Falls residents will still be able to enter I-86 toward Pocatello at the Exit 40 on ramp. They will progress eastbound until the Seagull Bay Exit 44 where they will detour through the exit and then re-enter the Interstate and merge with through traffic as it crosses back over from the westbound lanes.

Performing work on both bridges at the same time reduces costs and effects repairs in the same construction season. Once completed the new surfaces will be smoother and the bridge decks will be protected against further deterioration.

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 video describes how the new interchange will work and improve mobility and safety for the public – https://youtu.be/KRdVBAyXweA

Project details are available here on ITD’s projects website — https://itdprojects.org/projects/i-86-i-15-system-interchange/

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.

$111.9 million Contract Awarded for Pocatello System Interchange

POCATELLO – The Idaho Transportation Department has accepted a $111.9 million winning bid by Sundt-Cannon, a joint venture, to rebuild the I-86/I-15 system interchange at Pocatello. Work is scheduled to begin mid-July and will continue for approximately three years as the interchange undergoes modernization.

The old interchange was built in the mid-1960s and the aging and obsolete bridges need to be replaced. In addition, Pocatello and Chubbuck have grown significantly to the north of I-86 and east of I-15. Through traffic has also increased resulting in more congestion in the interchange.

Currently, a particularly challenging spot for drivers travelling west toward Chubbuck from the Pocatello Creek onramp. “Drivers have just 2,400 feet to move from the right lane to the far left lane to exit to I-86. This results in difficult maneuvers,” said District Engineer Todd Hubbard.

To eliminate this problem the new design will allow through traffic travelling north toward Idaho Falls to remain in a left lane. Motorists entering the freeway northbound from Pocatello Creek can continue north to merge with northbound traffic or they can merge with westbound traffic passing under a bridge to head toward Chubbuck. “This also eliminates traffic merging from the left coming from Chubbuck. That’s important because drivers expect merging traffic to come from the right,” said Co-Project Manager, Zak Johnson.

Construction will also include a significant change for Chubbuck Road. Currently the road passes over I-15 and has limited accommodation for bicyclists and pedestrians traveling toward the Wellness Complex. The new design makes Chubbuck Road into an underpass with sidewalk and bicycle lanes.

In addition, a north-south bicycle and pedestrian pathway is planned to help facilitate linking Pocatello Creek Road with the Portneuf Wellness Complex. This was designed in coordination with the Greenway Foundation. “Bicycle and pedestrian access to the Highland area was something the community saw as very important,” said Co-Project Manager, Greg Roberts.

The joint venture of Sundt Construction from Utah and Cannon Builders from Blackfoot is currently reviewing the project design and preparing a work schedule. Some equipment may be moved into position prior to the mid-July construction start date.

Motorists are encouraged to watch this I-86/I-15 Interchange overview video to understand how the new design will function. During construction it is important that drivers follow signage, slow down, and exercise caution.

Additional information will be posted as the project progress on the ITD I-86/I-15 System Interchange project page.

ITD Preparing Projects on I-86 Through Power County

AMERICAN FALLS – The Idaho Transportation Department is beginning the summer work schedule with several projects in the I-86 corridor through Power County. These projects include repairing the Rockland Exit 36 bridge, repairing the Sunbeam and Seagull Bay bridges, and a pavement preservation project along I-86 through Power County.

The Rockland Interchange repair is scheduled to begin in June and will consist of surface repairs, girder repairs, and the installation of a new waterproof membrane for the deck. Motorists should expect some delays.

The Sunbeam and Seagull Bay bridge repairs are scheduled to begin in early August. Both will undergo surface repairs and new concrete overlays. During construction, traffic will be moved to one side of the interstate via crossovers and slowed through the construction area. Motorists should expect some detours during this project.

The pavement preservation project will consist of a micro-seal application which is intended to extend the lifespan of the pavement. ITD currently plans to perform this work after the bridge repair projects are completed. The micro-seal application is scheduled to be completed by the end of September. During work there will be lane closures and reduced speeds in work zones.

Drivers are encouraged to check 511.idaho.gov or the 511 app for the latest updates on construction and road conditions.

Westbound ramp closure tomorrow at the Salt Lake Interchange

Image of traffic pattern change at Salt Lake Interchange

The westbound off-ramp at Exit 1 on Interstate 86 at the Salt Lake Interchange is expected to be closed tomorrow (Dec. 3) from 8 a.m. to 5:30 p.m.

Motorists heading west from Pocatello to Salt Lake will need to take Exit 216 at the Declo Interchange and re-enter I-84 toward Salt Lake. Eastbound traffic will not be affected by this closure.

Click here to see an image of the traffic pattern.

“This is follow-up work in connection to the closure that occurred late last month. It will be a short duration closure that will allow us to smooth the asphalt on the off-ramp,” Project Manager Travis Hitchcock said. “The asphalt work and additional signage installation are the remaining items left for this project.”

Drivers are urged to pay close attention to signage and message boards that will direct them through the area.

Wadsworth Brothers Construction of Draper, Utah, is the primary contractor on this project that involves replacement of an aging interchange with a new structure that will better serve motorists in the region.

Westbound ramp closure to begin tomorrow at the Salt Lake Interchange

The westbound off-ramp at Exit 1 on Interstate 86 at the Salt Lake Interchange is expected to be closed from 8 a.m. to 5:30 p.m. tomorrow and Friday (Nov. 19-20).

Motorists heading west from Pocatello to Salt Lake will need to take Exit 216 at the Declo Interchange and re-enter I-84 toward Salt Lake. Eastbound traffic will not be affected by this closure.

Click here to see an image of the traffic pattern.

“Work on the off-ramp must be done during the day when temperatures are high enough to properly seal the asphalt,” Project Manager Kenny Lively said. “This is one of the final steps needed for us to complete the project this winter.”

Drivers are urged to pay close attention to signage and message boards that will direct them through the area.

New traffic pattern in place next week at Salt Lake Interchange project

Image of construction on the Salt Lake Interchange project

As early as Thursday (Oct. 15), traffic will shift on Interstate 84/86 at the Salt Lake Interchange project. Motorists traveling toward Pocatello from Burley on I-84 will be detoured toward Salt Lake. They will take Exit 228 at Yale Road and then enter I-84 westbound and continue on to I-86 toward Pocatello.

“This detour will allow us to complete demolition of the aged eastbound bridge structure.” ITD Project Manager Travis Hitchcock said. “This will be the final demolition phase for this project.”

In addition to the Yale Road detour, westbound traffic progressing from I-86 to I-84 will now continue through the work zone in their designated lane of travel.

“These are new traffic patterns which replace others previously in place throughout this project,” stated Hitchcock. “It’s important that drivers pay close attention to signage and message boards that will be in place to safely direct them through the area.”

Traffic will remain reduced to a single lane in each direction. Drivers should continue to anticipate reduced speeds through the work zone and watch for crews and heavy equipment.

Wadsworth Brothers Construction, of Draper, Utah is the prime contractor on this project.