Bow River Basin - Water Supply Forecasts

Much-below-average natural runoff volumes are forecast for the March to September 2003 period in the Bow River basin (Table 4), due to near record low snowpack in the headwaters. Current forecasts range from 53 to 79% of average for this time of year. For most areas of the Bow River basin, the March 1 forecasts are slightly lower (by 2 to 5%) than last month's forecasts due to much-below-normal precipitation in most of the basin headwaters during February. The forecast for the Elbow River basin is similar to last month's forecast due to near-normal precipitation in the headwaters during February. Forecast volumes for the Highwood, Elbow, and Kananaskis Rivers are slightly higher than the rest of the Bow River basin because of near average soil moisture conditions. Current March to September 2003 volume forecasts are lower than runoff volumes recorded last summer, but are similar to or slightly higher than those recorded in 2001. Current forecasted volumes for the March to September 2003 period for the Bow River at Calgary would rank 11th lowest in 84-years of record (1912-95).