Cold weather paving in Idaho: how we do it and why it works

Paving, compacting and temperature testing occurring in Idaho with Fall leaves in the background.

 

The Idaho Transportation Department is overseeing more road construction than ever before. This work continues as temperatures are cooling and the ice and snow make their all-to-soon appearance. How does ITD successfully pave a road and have one of the shortest summer seasons in the country? Materials engineering and testing actually do make it possible.

 

Before asphalt pavement is ever laid, the surface where it needs to go is sprayed with a binder that will make it stick. This is called tack, a liquid made of oil and water. Tack must naturally break apart to become adhesive, separating as it lays across the surface where paving will happen. As it breaks, tack turns from a brown color to darker black, indicating that breaking has happened, and asphalt can be laid on top.

 

On the warmest of Idaho summer days, tack breaks in about ten minutes. When it’s colder, it can take hours. Still, with the right process, tack will break. ITD just knows it takes longer and plans accordingly.

 

Hot mixed asphalt is combined in a hot plant that can heat the components—crushed gravel and oil—to more than 300 degrees. This is dumped from a truck and spread using a paver, then compacted with a roller. ITD inspectors are on site anytime the contractor is, testing temperatures, compaction and much more to ensure that taxpayers get their money’s worth out of each project.

 

For quality compaction on state highways and interstates, the process must occur between 240-280 degrees. On warm summer days, asphalt must sit for a while after being spread before it is cool enough to be compacted. On colder days, asphalt loads hauled from hot plants are covered in transit to retain the most amount of heat. The asphalt will then be spread, and the roller follows closely behind to compact immediately before the material has cooled too much. All century-old, effective tricks of the trade in action.

 

“We don’t loosen up our requirements just because it gets cold,” ITD Materials Engineering Manager Mark Hayes said. “All contractors are held to the same quality materials standards and only operate when there are ways to do it right.”

 

Most of Idaho’s state highways run through rural areas, far removed from permanent hot plant locations. This fall, paving is occurring on State Highway 28 between Leadore and Salmon. The closest permanent hot plant sits in Idaho Falls, nearly four hours away. Enter the mobile hot plant erected by contractors at the ITD Leadore gravel pit, less than five miles from where the asphalt needs to be delivered.

 

In Rexburg, where paving is still occurring on multiple interchanges off U.S. Highway 20, the contractor’s permanent hot plant lies in Teton, less than ten miles away. Planning to have these proximities ensures that temperature requirements are met, and paving can be done successfully both earlier and later in the year.

 

Of course, there comes a cold enough ambient daily temperature that means paving operations are simply no longer viable. ITD requires that the temperature be 40 degrees and rising for paving to happen, which can result in fewer hours to pave during the fall but still allows a window of work. The right equipment, materials, planning, testing and operating tricks of the trade make it so ITD and contractors can pave with quality even when it is colder outside.

 

When you see paving equipment and a compacting roller working close together while your heater is on inside your car, know that ITD and the industry have the brief Idaho summers and cold Idaho temperatures on tap. That new road surface will meet the same metrics as summer paving, ensuring it lasts for many years to come.

US-20 South Rexburg Exit to close starting Monday

Road closed signs at Exit 332 on US-20 in Rexburg.

REXBURG­­—U.S. Highway 20 Exit 332 for University Boulevard in Rexburg will fully close starting Monday, September 30, for crews to complete final paving and striping operations. Work is not expected to take more than a few days, and the exit will be re-opened as soon as it is completed.

This closure was purposefully scheduled during Madison School District’s harvest break to least affect traffic. Detours include Exit 328 (Thornton), Exit 333 (Main Street) and Exit 337 (North Rexburg). After re-opening next week, construction work at Exit 332 will be minimal and off the roadway.

Construction does continue at Exit 333, with one lane running in each direction. These projects to create safe and efficient diverging diamond interchanges at both Rexburg exits are still expected to be complete later this fall.

For more information about this project, visit https://itdprojects.idaho.gov/pages/us20rexburg. Drivers can also use the 511 app to see current status on this and other Idaho projects.

The Unhailed, Underappreciated Emergency Responders

SH-33 with road blockades and a pickup truck following an accident

 
People see the Idaho Transportation Department logo and seem to have an automatic response, for better or worse. They’re the ones causing construction delays, needing to get the snow off the road already, or taking too long whatever they’re doing. They don’t do anything right and never will. Their flashing orange lights could just as easily be the mailman.

It’s not likely that you think of ITD as being the ones to first call 911, the ones to keep you from freezing or assess injury at the side of the road. They’re not your emergency responders. But then again, yes, they are.

All across Idaho, there is no one that travels the over 12,000 lane miles of highways and interstates more continually than the men and women behind the blue and orange ITD logo. The likelihood that they’ll be there when a crash or emergency occurs is higher than anyone else. The police and ambulance have to be called in. ITD is already there.

When two crop duster planes collided and crashed alongside US-26 near Arco, an ITD striping crew was there, becoming the first to assess the pilots. When a motorcycle crash occurred on Interstate 15 near Dubois, part of the ITD maintenance crew was there, already working the roads they consider their own. The story is similar in the case of many incidents across Idaho over the years.

“We spend so much time on the road, that nine times out of ten, we’re the first on scene when anything happens,” Idaho Falls area foreman Jared Loosli said. “And we’re not just going to pass by and leave.”

In the instance of a recent multi-fatality crash near the I-15/ US-20 interchange, Loosli and his crew were called in immediately to assist the Idaho State Police. Most people don’t realize that when state troopers get called out, ITD is almost always called out too.

“We have great foremen for ITD here in Idaho,” ISP Lieutenant Marvin Crane said. “We have personal relationships with them, and they never say they can’t do something. They’re always asking, ‘What do you need?’ and getting things done within minutes.”

“It does affect you,” Loosli stated, also noting that the worst incident he’s ever been a part of happened to one of his own guys.

“The first thing I’m thinking about is my crew,” Ashton/ Island Park foreman Ryan Wright added. “At that point, there are no traffic devices, there’s not time and it’s not the priority. It’s just our guy in the middle of everything trying to help.”

Very recently, Driggs/ St. Anthony Foreman Lucas Richins witnessed what all ITD foremen prioritize and fear the most. An ITD maintenance worker was hit after a distracted driver ran through a roadblock while powerline repair work was being done on SH-33.

So not only are ITD employees unhailed first responders, they’re also the underappreciated workers putting their lives on the line every day. Earlier this year, three of Loosli’s crew were removing hazards from I-15 when a semi grazed the side of their vehicle, damaging the rear end and taking off the driver’s side mirror. A mere two inches would’ve changed the outcome of that incident entirely.

What is it that keeps the guys in yellow working in these risky situations and responding to emergencies, knowing full well that public opinion is often negative and even rude?

“These are small communities,” Mackay/ Challis foreman Jeremy Johnson noted. “When we go out on a call, it could very well be our own friends and families. We’re thinking of keeping them safe in everything we do.”

“When I’m doing something myself, I can see the progress and know that I’m making things safer for everyone,” Wright shared. “I actually love to go out plowing. I love what I do.”

“It’s really a mentality,” Loosli says. “You either have it or you don’t honestly. People complain because they drive by and see four guys standing around. But we know why, we see the bigger picture and the process. The 30 seconds people see isn’t the story of the whole 10-hour day at all.”

“On instinct, I’m thinking about what I could have done, how could this have been prevented?” Richins said. “But then the biggest thought becomes frustration. We’re here trying to help and to serve. When we close a road, the whole point is to keep people safe. Driver awareness is so negligent that it really is frustrating. It’s dangerous.”

Adding to the dangerous nature of the job is the reality that the ITD fleet are not considered emergency vehicles, and ITD signage is too often not respected. Multiple layers of striped road blockades or orange traffic barrels somehow don’t always keep people out.

“We don’t enjoy closing a road or causing delays,” Richins emphasized. “We do it and we have to because it is the safest way. People need to be patient and have respect.”

“I don’t need to be liked,” Wright added. “I’m still here to do a job and to protect people.”

So maybe the next time you barely notice the flashing orange lights of an ITD vehicle alongside the road, want to scream in standstill construction traffic or at being stuck behind a plow, you’ll slow down and think too that those folks in bright yellow are also the ones who will be there before anyone else can. They could be the difference between freezing after sliding off the road or staying warm until the tow truck gets there. They could be the one to help make sure that your own family and friends across our tight-knit Idaho communities are given emergency support in time to matter.

It’s even highly likely that they will be.

US-20 Exit 333 in Rexburg re-opens

Aerial map and graphic descriptions of how to drive the diverging diamond traffic pattern at Rexburg Exit 333

REXBURG— U.S. Highway 20 Exit 333 in Rexburg will re-open Thursday night with a new diverging diamond interchange in place. This exit has been closed since late July so the Idaho Transportation Department and contractors could construct the new road design and complete vital underground infrastructure work.

The re-opening comes in time for an increase of traffic as university students arrive in Rexburg for the fall semester. All lanes of traffic will be open and construction efforts remain off the roadway at both Exit 332 (University Boulevard) and Exit 333 (Main Street) through this weekend to accommodate this influx.

“There really is a light at the end of the tunnel in Rexburg,” ITD Project Manager Conner Huffaker said. “We’re excited to be giving people some relief from construction and know that these new exits will do a great job of keeping everyone safe and moving better. Thank you for bearing with us.”

Motorists and citizens should be aware that construction efforts will continue again next week and through the month of October. Intermittent single-lane closures will be in place, with traffic still able to move through the interchanges. Impacts will be noted on 511.idaho.gov.

University Boulevard Exit will fully close again during the week of September 30 through October 4 to allow crews to add a final layer of pavement. This timeframe has been selected in coordination with when Madison School District is out of school for harvest break. Work on both exits is on track to be completed late this Fall. For further details about this project and to watch a video on how to drive the new diverging diamond traffic pattern, visit itdprojects.idaho.gov/pages/us20rexburg.

US-20 Exit 333 to remain closed through Labor Day

US-20 Exit 333 into Rexburg with construction markers and road closed barricades in place.

U.S. Highway 20 Exit 333 for Rexburg will remain closed through Labor Day weekend and into next week. Contractors and crews have encountered multiple difficulties on site, including the breakage and repair of a main sewer line last week, causing unanticipated delays. The Idaho Transportation Department is now committed to Exit 333 being open ahead of the influx of university traffic on Friday, September 13.

While this primary exit into Rexburg has been closed during the month of August, ITD and contractor partners have repaired and rebuilt multiple city utilities, constructed and repaired drainage and irrigation systems, as well as removed and reconfigured the road itself. This work takes additional operational time now but will save city and community partners from having to close the roadway for infrastructure needs in the future.

“We know that Rexburg has endured a lot with construction this summer,” Project Manager Conner Huffaker said. “We hope people will continue to be patient for just a little longer and know that the end outcome will be a major improvement for the long-term future.”

Completion of all work on both Exit 332 for University Boulevard and Exit 333 for Main Street is still expected to be completed by late fall. Motorists should plan for continued construction near the interchanges until that time, with at least one lane of traffic open in both directions.

Exit 333 will reopen with the same diverging diamond interchange design as is now operating at exit 332. This traffic pattern is far more efficient than what was in place before and will greatly improve travel to and from Rexburg.

Further details about this project and how to drive the new design can be found at itdprojects.idaho.gov/pages/us20rexburg.

###

Public invited to view latest information on study to improve US-20 from Ashton to SH-87 JCT

Photograph of US-20 in Island Park

The Idaho Transportation Department (ITD) will host two public meetings next week to share developments and seek public input for the preliminary environmental study of U.S. Highway 20 between Ashton and the State Highway 87 junction.

The purpose and need of the corridor study is to enhance highway safety and operations by decreasing crash severity, addressing traffic growth, improving access management and addressing regional freight movement.

Following a two-year process that included significant analysis and public involvement, including a stakeholder screening group, several improvement options are recommended to move forward and will be on display at the public meetings. The options included various four-lane highway alternatives being considered.

The option of adding more alternate passing lanes was determined by the stakeholder screening group to be least beneficial and will likely not be recommended to proceed because it does not meet the purpose and need requirements of improved safety and mobility. Future traffic data estimates indicate this option has excessive congestion and travel delays by 2050 and a concern by engineers that this inconsistent lanes design over 40 miles of mountain highway with more than 10,000 vehicles a day during peak season creates high risk crash zones at multiple traffic merge areas versus other options reviewed.

The study is a first step in efforts to reduce congestion, enhance safety, and improve mobility throughout the region. Public input is important to the process and ITD welcomes feedback on study alternatives. Recommendations from the study may be used or adopted into future National Environmental Policy Act (NEPA) studies, which will also include community outreach and public engagement opportunities. Funding beyond the PEL study has not been identified.

ITD experts will be available to answer questions and discuss the alternatives and timeline of the study. The format and content will be the same at both meetings. The locations are:

Ashton Community Center and Library

925 Main Street
Ashton, ID 83420

August 21, 2024
5 – 7 p.m.

Island Park EMS Building
4378 County Circle
August 22, 2024
5 – 7 p.m.

For those who can’t attend in person, an online meeting will be available from August 22 – September 5 at itdprojects.org/projects/us-20-ashton-to-sh-87-jct/.

US-20 Main Street Exit in Rexburg to fully close Monday

Construction at Rexburg Exit 333, which will be fully closed on Monday, July 22 through August

 

REXBURG­­—The Main Street Exit for Rexburg on U.S. Highway 20 will fully close beginning next Monday. The closure at Exit 333 will allow the Idaho Transportation Department to efficiently construct a diverging diamond interchange (DDI) like the one now operating at University Boulevard (Exit 332). The closure is expected to last through the month of August.

All ramps at Exit 333, as well as Main Street between the ramps, will be closed to traffic and detoured to nearby interchanges. Through traffic on US-20 will be unaffected during construction.

Detours include Thornton (Exit 328), University Boulevard (Exit 332), and North Rexburg (Exit 337). A new permanent traffic signal will be in place and operating to aid the flow of traffic at the North Rexburg Exit prior to this closure. One-lane closures are in effect at the University Boulevard Exit while construction efforts continue there.

“We thank everyone for their patience and understanding in dealing with road construction in Rexburg this summer,” Project Manager Conner Huffaker said. “We really are trying to keep traffic flowing and minimize the impact on people as much as possible. There’s a lot to get done in a short amount of time and all of it will make travel in Rexburg better once it is.”

Businesses near the Main Street Exit remain open, with alternate access available and signed. Construction crews will also coordinate with emergency responders to ensure access through the closed work zone when needed.

The city of Rexburg and ITD completed a cooperative agreement during the planning phase of this project to have the contractor complete city requested work items, including a sewer repair during road construction. Crews will insert a manhole and repair a damaged sewer pipe so that additional closure for this needed infrastructure work won’t have to occur in the future.

Construction of all Rexburg US-20 interchanges is expected to be fully complete in late October. More details about this project can be found at itdprojects.idaho.gov/pages/us20rexburg.

Pavement repairs begin across eastern Idaho this summer

Pavement improvements on east Idaho road

RIGBY— The Idaho Transportation Department is utilizing the summer window of opportunity to resurface and repair several roadways across eastern Idaho. Pavement overlays and repairs increase the strength and longevity of our roads, helping them to better withstand the weather conditions in this region. Beginning mid-July, motorists can expect to see traffic limited to one lane as needed in the following work zones:

  • Interstate 15, milepost 112 at Bingham County line to Exit 119 at U.S. Highway 20 Interchange. Work in this area through Idaho Falls will be conducted at night from 8 p.m. to 6:30 a.m. Traffic will be limited to one lane intermittently in both directions where crews are actively working. Work is expected to last approximately three weeks.
  • I-15 Exit 119 to Exit 143 at Sage Junction. Traffic will also be limited to one lane intermittently in both directions where crews are actively working. Work on this section of the interstate will be conducted during daytime hours and last until mid-October.
  • US-20 from milepost 264 at Bonneville County line to milepost 301 at the Idaho National Laboratory junction. Beginning mid-July, patch and repair work will be underway, with flaggers and one-lane closures in the working area. This section of road will also undergo a seal coat later in August. Work is expected to be complete by mid-August.
  • State Highway 28 milepost 101 at Lemhi River Bridge to milepost 125 at Baker, and milepost 305 to 306 on SH-93 in Salmon. These pavement projects require that a mobile hot mix plant be set up closer to the area of work so asphalt temperatures can be kept where they need to be to correctly build the road. This operation entails equipment parts and pieces being hauled with large transport trucks and then constructed at the Leadore state gravel pit. Once the plant is set up and operational, work is anticipated to last approximately eight weeks. Expect one-lane closures along SH-28 with pilot cars and flaggers in place.
  • SH-93 milepost 108 at Mackay to milepost 115 at Mackay Reservoir, and milepost 139 at Willow Creek Summit to SH-75 junction. Traffic will be limited to one lane intermittently using pilot cars and flaggers in the current working area. Both lanes will be open again overnight. Work is expected to begin late July and last until mid-September.
  • US-26 northeast of Craters of the Moon visitor center from milepost 230- 240. This section of road will be dug out and replaced with new pavement. Pilot cars and flaggers will direct traffic through one lane. Work is expected to be complete in just six days, beginning in early August.

Remember to use caution and stay alert when traveling through work zones. Up-to-date information on these projects is available by visiting 511.idaho.gov, dialing 5-1-1, or downloading the 511 app.

US-20 Exit 332 to re-open in Rexburg, expect continued construction

Graphic of US-20 Exit 332 detailing how to drive through a diverging diamond interchange

University Boulevard Exit 332 in Rexburg will re-open by Wednesday morning. The exit has been closed since May 29 to allow the Idaho Transportation Department and contractor partners to efficiently construct a diverging diamond interchange (DDI) that will improve traffic flow and safety.

Motorists should be aware that work to finish construction at Exit 332 will be ongoing until mid-October. Paving, striping, infrastructure, and beautification efforts will create the need for occasional lane closures. One lane of traffic in each direction will remain open during these instances.

With Exit 332 re-opened, Rexburg Main Street Exit 333 will be fully closed beginning in late July so the same DDI traffic flow can be built there. More information about that closure will follow in the future.

Stay up to date on further status of this project and others by visiting 511.idaho.gov, calling 5-1-1 or downloading the app.

Idaho Transportation Department seeks feedback on draft seven-year transportation plan

Drone shot of I-90 weaving through the mountains in North Idaho

The Idaho Transportation Department (ITD) is seeking feedback on the just-released draft Idaho Transportation Investment Program (ITIP). The ITIP outlines the state’s transportation priorities and guides investment decisions for the next seven years through 2031. ITD encourages everyone to review the draft and provide comments July 1-31.

Transportation projects included in the draft ITIP range from large-scale interstate improvements to smaller projects like the installation of new guardrail. Projects are located throughout Idaho’s 44 counties and involve all modes of transportation. Project selection is determined through technical data, as well as input from local officials and residents.

Visit itd.idaho.gov/funding to view an interactive map to learn about projects and submit a comment through the portal.

This draft ITIP shows plans for $6.9 billion in funding, including $200 million dedicated to pavements and $100 million dedicated to bridges each year.

Chief Deputy Director Dan McElhinney confirmed, “With the growth of traffic accelerating the need for improvements and the impacts of inflating costs since 2020, the added annual investment in highway pavement and bridge repairs proposed in this draft ITIP plan will provide the Idaho Transportation Board effective options to consider looking ahead for Idaho.”

Comments can be emailed to itipcomments@itd.idaho.gov, recorded at 208-334-8063 or mailed to:

ITIP – Comments
Attn: Abby Peterson
P.O. Box 7129
Boise, ID  83707

Paper copies of the ITIP will be available at regional offices and provided upon request by contacting the Idaho Transportation Department at 208-334-4455.

All comments will be reviewed and incorporated into the ITIP where appropriate. Responses will be sent by September.

After approval by the Idaho Transportation Board in September, the ITIP will then be submitted to the Federal Highway Administration, the Federal Transit Administration, and the Environmental Protection Agency in October.

Public input is crucial in ensuring that the ITIP includes the prioritized needs of Idaho’s communities.