Hydrology and Water Balance Study for the Canadian High Arctic Community of Grise Fiord: Fid-Bau Portal

Hydrology and Water Balance Study for the Canadian High Arctic Community of Grise Fiord

Keung, Chris / Johnson, Ken / Gretton, Joel / Alamgir, Aurangzeb

In the Canadian Arctic, drinking water availability is scarce and vulnerable to changes such as climate change impacts and increasing community development. A hydrological and water balance study was completed to determine if various surface water sources that rely on snowfall and snowmelt-generated runoff could meet current and future 20-year water supply needs for the High Arctic Nunavut community of Grise Fiord, the most northerly community in Canada. The study is focused on a coarse-resolution analysis to characterize annual watershed yield versus expected water use of the community and accounts for annual municipal water supply usage, population growth, and potential impacts of climate change. High-Resolution Digital Elevation Models were used to delineate potential watersheds using ArcGIS. A water balance model was used to predict the annual water yield from each potential watershed using historical and projected future climate data. Climate scenarios were analyzed using below-average values for precipitation rates and above-average values for evapotranspiration rates to account for worst-case scenarios. The watersheds represent nival regimes which are characterized by negligible winter flows (typically between October and early May), followed by significant flows in the summer from ice melt and thawing snowpack. From the analysis, the existing runoff source at Grise Fiord is not reliable or sufficient to meet the future water supply needs of the community. It was recommended that the community uses the alternative primary water source identified in the study (Airport River) as this source can meet the community’s future needs. The alternative water source will require constructing a new water intake and raw water storage infrastructure (storage tanks) in addition to the new water treatment facility.