Abstract Manager

Remote Indigenous communities in Northern Canada rely on winter road networks for essential supplies and connectivity; however, the increasing frequency of warmer winters has significantly shortened the operational window for these seasonal roads. In Northern Ontario, a specific river ice crossing was identified as the critical link of the network, as it is often the last crossing to open each season. This project implemented a systemic climate adaptation strategy to minimize weather-dependent infrastructure failure through proactive engineering. Through a multi-disciplinary assessment, the designers identified that the local geology contained extensive eskers, which would be beneficial for the routing strategy. Eskers are elongated ridges composed of stratified sand and gravel deposited by meltwater streams flowing in tunnels beneath a retreating glacier. Unlike the surrounding low-lying muskeg and peatlands, eskers provide superior natural drainage, high bearing capacity, and elevated terrain that promotes earlier seasonal freezing and resists the thermal degradation of the subgrade. Consequently, the design included the replacement of the vulnerable ice crossing with a permanent bridge, and 8.8 km of new winter road and 15.6 km of all-season road alignments along the elevated esker ridges to provide a stable, long-term subgrade for future permanent upgrades. Additionally, the design team collaborated with the community to optimize the road geometry by following existing harvest corridors in a portion of the project area, which were already established and maintained by the community. While this required adopting reduced design speeds, it maximized the utilization of established infrastructure on resilient terrain and significantly reduced the project’s environmental footprint. The final design successfully transitions this community from a reactive, weather-dependent state to a proactive, resilient posture. By establishing a reliable, high-ground corridor, the design ensures the community is equipped for rapid emergency evacuations and the delivery of essential services during severe weather events, offering a model that can be adapted to other northern communities in Canada.