Ask Binay Yadav about the challenges of building roads in the North and he will speak for six minutes, uninterrupted. As the director of transportation within the Government of the Northwest Territories’ (GNWT) department of infrastructure, Yadav is intimately familiar with the many difficulties of northern road construction: from extreme weather conditions and a lack of skilled labour, to a short season and a dearth of quality materials. Plus, building new roads and maintaining existing ones is — like everything else up here— more expensive than it is down south.
Another significant factor? The effects of climate change. Thawing permafrost and increased precipitation lead to potholes, cracks, frost heaves, and washouts — all things we’re likely to see more of as temperatures warm. “These are continuous challenges to us for our design, construction, maintenance, and operation of our roads,” Yadav says. “If there is any degradation in permafrost [under or along the road], it’ll influence surface conditions right away.”
Permafrost that isn’t permanent will be the biggest challenge for northern infrastructure in the near future. Luckily, some clever people are working on potential solutions. Using cutting-edge techniques and groundbreaking — literally — materials, we just might be able to save the northern roads melting under our feet.
DRIVE Dawson City‘s Front Street and you’ll notice that it’s not black like other asphalt roads. It’s grey. When the street was paved in 2009, a base layer of asphalt concrete was overlaid with a grey-coloured synthetic binder.
The reasons for the atypical colour were twofold: first, the community wanted the road to fit with the town’s historic appearance — and its gravel roads. And second, there were concerns that standard black asphalt would absorb more of the sun’s rays and promote thawing in the permafrost under the road. “We keep using black material on top of airstrips and roads, either surface treatments or asphalt,” says Guy Doré, an associate professor in Laval University’s civil engineering department. He has studied the effects of permafrost on infrastructure for over 20 years. “And when the roads start to deform and dips are forming at the surface, we fill with new black material. We keep exacerbating the problem.”
Up until that point, Front Street had been paved with a bituminous surface treatment, also known as chipseal, which is typical for northern roads. Yadav says chipseal is a better option for the North than the hot-mix asphalt used down south because it’s cheaper and easier to pave long, low-volume roads, since you don’t need specialized equipment or as much manpower.
The grey synthetic binder on Front Street, meanwhile, has held up well in the years since it was paved thanks to its ability to better reflect sunlight. It’s effective, but it’s also very cost-prohibitive.
According to a 2009 paper produced by the Yukon government, the synthetic binder cost more than five times as much as standard asphalt cement. The expense is in large part because there’s little production of synthetic pavement in North America. It’s much more widely made and used in Europe. The synthetic binder used on Front Street was manufactured in France, shipped through the Panama Canal to Vancouver, and trucked up to Dawson.
As urban centres continue to heat up, lighter-coloured asphalt may become more and more in demand on this side of the Atlantic, leading to more localized production and reduced cost. But for now, it remains an expensive option. Another material that’s seen some success in the North is geotextile. This plastic and polypropylene cloth isn’t new — it’s been used for decades to reinforce roads by better distributing the load of traffic, helping with drainage, and reducing settlement.
The NWT government has tested the fabric on Highway 3 between Behchokǫ̀and Yellowknife, and used it on the entire Inuvik-Tuktoyaktuk Highway (ITH). In the Yukon, it’s been used on the Dempster Highway and the North Klondike Highway near Fox Lake. Both the Yukon government and GNWT are also testing new ways of stabilizing existing roads using culverts made of plastic (high-density polyethylene, to be specific) instead of the more commonly used steel. The thought is that polyethylene will transmit less heat to the ground, causing less thaw.
Yadav says his department is logging data on a plastic culverts they’ve inserted along the ITH at kilometre 22. Jim Regimbal, northern area superintendent in the Yukon government’s department of highways and public works, says his department is considering plastic culverts with heat tape in them in areas on the Dempster Highway where glaciers have been moving onto the gravel road in the last few years.
Near the Yukon-Alaska border, Fabrice Calmels and re-searchers from multiple universities spent years studying ways of stabilizing permafrost. Along a stretch of Alaska Highway near Beaver Creek, 12 test sections employed various methods, including an air convection embankment—a layer of porous materials placed underneath a roadway—and clearing snow along embankments. Calmels, the research chair of permafrost and geoscience at Yukon University’s Research Centre, has been studying permafrost at the school since 2012. “We really look at the landscape as a whole and how the road is interacting with this landscape,” he says.
At the test site, two techniques were ultimately implemented: snow or sun sheds—a covering over the road that prevents snow accumulation and solar radiation—and heat drains —a permeable drainage blanket installed in or along an embankment.
Also near Beaver Creek, about 30 kilometres east of the community, a series of thin, white pipes lines one side of the highway. Installed in 2020 by the government, after research by Calmels and others, these thermosiphons help extract heat from the ground in the winter. The department is now collecting data on how they perform. These kinds of technology just weren’t
available during road-building in past decades, but they’ve become more and more useful. For the last three to five years, the Yukon government has been using drones in areas along highways prone to landslides and avalanches to get a better understanding of the disasters before they strike.
When Thurber Engineering began designing the Tłı̨chǫ Highway between Whatì and Highway 3 in 2018, the first order of business was figuring out its optimal path. And that, says David Field, the project’s geotechnical design engineer, meant trying to avoid permafrost and soggy ground— something that wasn’t always done in the past. “If you’ve ever driven out just west towards Fort Simpson, there’re some roller-coaster sections of road, because they’ve traversed big areas of either frozen ground or peat [when they built that road],” Field says. “Over 40, 50 years, it just turns into a roller coaster.”
Based in Calgary, Thurber did as much remote analysis as possible before putting boots on the ground. That involved technology called bare-Earth LiDAR, which uses pulsed lasers to create an elevation map of the Earth’s surface without any trees or vegetation on it. Field says they also used drones to take aerial photos and videos to get a better sense of the terrain.
If territorial and municipal budgets had no limits, all these technologies could be implemented and our roads would b a whole lot better than they are now. But we live in reality, where the dollars are finite.
“You’re looking at three, four times more expensive to construct with those techniques than without those,” says Doré of measures like thermosiphons, air convection embankments, and sun sheds.. “Though many of these techniques work very well and are, to my point of view, cost-effective.” The cost is one reason why these tools haven’t been widely rolled out. Their long-term viability is unclear, too; they’ve only been tested in small sections of highway for a couple years at a time. And as winters continue to warm, their efficacy will decrease, says Doré.
Governments’ budgets will have to grow, he adds, or else we accept that Northern roads will be very poor quality — even more so than they already are — and possibly dangerous. A cheaper option is designing for the North. Unfortunately, Doré isn’t seeing that happen as much he’d like. “Even if there was no climate warming, we’re still doing a bad job in designing in the North,” he says. “We still are using, too often, the southern standard without adapting those standards to the North.”
One example are the slopes along roadways, which are often built with a grade of two meters horizontal to one metre vertical, the way they are down south. Instead, Doré says, embankments should have gentler slopes in the North — 4:1 or 6:1 — so that precipitation doesn’t accumulate so dramatically. Snow and water are the “worst enemy” of permafrost, Doré says, because they insulate the ground and cause thaw.
On the Tłı̨chǫ Highway, Thurber Engineering designed the road’s bridges to allow for easy adjustment as the gravel road settles over the years. They designed concrete transition slab at the two ends of each bridge that can be pulled off the ground with a crane. Then more gravel can be added underneath the road, and the slab put back in place.
“The last thing you want is the approaches to your bridges pushing your car up in the air or banging your head against the ceiling of the car,” Field says. “It’s an effective way for roads that are in remote locations to deal with settlement over time, because it’s very easy to fix.”
Another glaring issue that Doré sees is the lack of Northern design standards. Many different agencies — territorial governments, the Canadian Standards Association — are developing guidelines, but the problem is there’s no national leader.
“I think that, with the complexity and the magnitude of the problem in the North, there’s no way a single agency can deal with those things,” Doré says. “There’re many players and it’s very difficult to coordinate all the efforts.” In his view, Transport Canada’s now-defunct Northern Transportation Adaptation Initiative would have been ideal for leading the charge, and it did have plans to develop Arctic engineering guidelines. But the federal government ended the program in 2021, deciding that Environment Canada would oversee initiatives related to climate change instead.
“Unfortunately, Environment Canada is less oriented towards practical solutions for northern infrastructure,” Doré says. He believes more education is what’s needed to better plan for Northern infrastructure. As Doré points out in a 2022 paper he co-authored for the University of Calgary, most civil engineering programs at Canadian universities don’t offer courses in Arctic engineering, nor do provincial or territorial licensing bodies require training specifically pertaining to permafrost and sensitive environments. In Alaska, on the other hand, obtaining a professional engineer license requires the completion of an Arctic-engineering course.
“It is highly concerning to see that the lack of experienced and qualified personnel, as well as the scarcity of guidelines and standards on Arctic engineering, still leads to poor designs and premature failures,” Doré and his co-authors wrote.
A recent partnership between Canadian and Norwegian universities developed three courses in permafrost engineering and northern infrastructure that were taught last year at Yukon University, the Norwegian University of Science and Technology, and the University Centre in Svalbard. Called “Frozen Canoes,” the initiative ended in December 2022, after five years of funding from the Research Council of Norway.
Ironically, the best option might be to speed up the thaw. Or, at least, control it. Doré thinks what may soon be the only viable way to deal with permafrost is to intentionally thaw the ground before construction.
“You can expose the ground to solar radiation two or three years prior to construction,” he says, “just to let the natural condition cause permafrost degradation, and then build your embankment when the permafrost has degraded to a depth that you designed to make sure that the system will remain stable for the design life of the structure.”
In fact, this method dates back to the Klondike Gold Rush, when miners tried to heat the ground with wood fires, hot water, and eventually steam boilers and pipes. When we built roads back in the 70s and 80s, we didn’t think about the possibility of weather conditions changing in the decades to come.
“The general feeling was that building on permafrost was like building on bedrock... you’re stable forever,” says Doré. We know better now. “Now when the system is designed, it’s designed taking into consideration the expected climate in 20 or 30 years,” Calmels adds. “So you tend to increase the capacity of the system based on the expected future climate.”
Building roads in the North requires a different approach than road construction down south. And ideally, in the very near future, a better one.
