Protection of Utilities Against Permafrost in Northern Canada

Construction on Permafrost

“…Continuous circulation is maintained by bleeding to the sewer at each house and at dead ends in the mains or by dual-main distribution, as at Yellowknife, or single-main recirculation, as at Fairbanks, Alaska. At Yellowknife the installation of municipal services appears to have thawed the relatively ice-free, frozen sandy soils without causing any difficulty (Copp et al 1956). At Thompson, Manitoba, when permafrost was encountered, trenches were excavated and backfilled with granular materials several feet below the pipe grade (Klassen 1965).…”

Water Supplies in the Central and Western Canadian North

“…The moss provides good insulation by entrapping large amounts of air and supporting a heavy blanket of snow. In practice, moss has been demonstrated to be almost valueless as insulation around buried pipes, however, because it becomes water-saturated when buried (4).…”

Water supply and sewage disposal in permafrost areas of northern Canada

“…Studies carried out on the Yellowknife water system in which moss was used around the pipes as insulation, suggest that it is of little value when used below grade unless it can be kept dry. 4 Wet moss is not a good thermal insulator; when present at the surface, it protects the permafrost through the mechanism of evaporation, but, when placed around pipes, this process cannot take place and its insulating value is therefore reduced.…”