Inuvik to Tuktoyaktuk Highway Road Embankment Constructed on Ice-Rich Permafrost Terrain

ABSTRACT: The Inuvik to Tuktoyaktuk Highway (ITH) crosses delicate tundra and continuous ice-rich permafrost terrain along the 137-km length of the two-lane gravel surfaced road. To protect the permafrost, a fill-only embankment design approach was employed, and construction took place during winter months when frozen soils from local borrow sources were placed on the frozen tundra to preserve the underlying permafrost. Pre-design geothermal evaluations were conducted to support the road embankment design. The design basis was to limit the annual thaw into the original ground beneath the core of the embankment and promote permafrost aggradation into the original active layer. After highway construction was substantially completed, ground temperature cables were installed at predetermined locations along the alignment for long term monitoring. This paper presents an overview of the ITH embankment design and construction approach addressing the challenging permafrost conditions along the highway alignment, and presents some post-construction ground temperature data collected in 2017.