The stable isotope composition of water and major-ion concentrations were measured in a small catchment tributary to Manners Creek, situated in the zone of discontinuous permafrost near Fort Simpson, Northwest Territories. Hydrograph separation calculations based on δ18O and δ2 H values of snow, active-layer water, and streamflow reveal that snowmelt contributions were secondary to active-layer storage contributions throughout the spring freshet period of 1990. At the time of peak spring runoff an estimated 40 to 50 % of streamflow was contributed by snowmelt, while over the entire spring period only 25 to 30 % of streamflow was contributed by snowmelt. Overland and pipe flow are shown to be important mechanisms of rapid snowmelt runoff from permafrost slopes.
- Received September 22, 1992.
- Revision received February 4, 1993.
- Accepted February 12, 1993.
- © IWA Publishing 1993