Construction of a highway on permafrost poses challenges, with experts emphasizing the importance of ongoing maintenance for projects like the Arctic economic and security corridor. Despite permafrost roads being a longstanding feature in the north, a changing climate is impacting these projects. Ground temperatures are rising, leading to shorter winters and increased project costs, particularly as the government considers expediting the Arctic economic and security corridor from Yellowknife to Grays Bay, Nunavut.
This 900-kilometre utility corridor is envisioned to support navy vessels and large cargo ships for transporting materials from potential mineral mines in the Northwest Territories and Nunavut. Over the past two decades, permafrost temperatures in some Arctic regions have climbed by up to 1.2 degrees Celsius per decade, as highlighted in Canada’s Changing Climate report from 2019.
Guy Doré, an emeritus professor at Université Laval specializing in civil engineering, has extensively researched the impact of thawing permafrost on transportation infrastructure for four decades. He advocates for adapting corridors to avoid issues caused by permafrost thaw. In regions like the N.W.T., where the Inuvik-Tuktoyaktuk Highway is showcasing signs of distortion due to thawing permafrost, experts like Jim Stevens emphasize construction techniques that minimize ground disturbance to limit permafrost degradation.
Various strategies, such as layering materials like gravel and synthetic fibers on top of permafrost to provide insulation, have been explored by researchers like Doré along highways such as the Alaska Highway. While these methods can help preserve permafrost, they are not foolproof, and road repairs are still expected periodically. Adequate funding for long-term maintenance is crucial to address issues like distorted roads and potholes resulting from permafrost thaw.
In the case of the Inuvik-Tuktoyaktuk Highway, which has faced maintenance challenges, the N.W.T. Infrastructure department has allocated increasing funds for upkeep, including gravel surfacing and embankment slope repairs. Additional support from federal and territorial governments, such as the $14 million pledged for highway rehabilitation in 2023, further underscores the ongoing commitment to managing infrastructure projects in permafrost regions.