Water yield and streamflow trend analysis for Alberta watersheds

When we add to Alberta’s natural diversity of water availability the population distribution, where most Albertans live in the southern third of the province, and water intensive industries, such as irrigated agriculture in the prairies or the oil sands industry around Fort McMurray, the question arises if there is enough water for every user. [...] For example, glaciers within the Cline River watershed, the main headwaters of the North Saskatchewan River watershed, contributed an average of 8% of the mean annual streamflow (1961-1990), with a maximum streamflow contribution of 29% (Nemeth et al., 2010). [...] Due to the timing of glacier melt, which on the eastern slopes of the Alberta Rocky Mountains peaks in July, August and September, declining glacier melt contributions to streamflow will result in a decline in summer and fall streamflows. [...] According to IPCC (2007), the combined consequences of increased future air temperatures and precipitation amounts (mainly lower in the southern parts, mainly higher in the west-central and northern parts) will result in a decline of streamflow in southern Alberta and an increase in streamflow in northern Alberta during the next 100 years (Sauchyn et al., 2008). [...] Objectives As the watershed is the natural hydrological unit within which all hydrological inputs and outputs occur – with the possible exception of groundwater in- and outflows -, the spatial units for the water yield and trend analyses are Alberta watersheds with complete or almost complete streamflow records for the period 1971-2000.