Bow River Basin - Water Supply Forecasts

As of April 1, 2007, natural runoff volumes for the March to September 2007 period are forecast to range from average to above average in the Bow River basin. Natural runoff volumes are expected to be above average at Banff, Calgary and into the Cascade Reservoir, average to above average into the Spray Lakes Reservoir and for the Kananaskis River, and average for the Elbow and Highwood Rivers (Table 5a). Current natural runoff volume forecasts range from 93 to 111% of average in the basin. Current forecasts have risen 2 to 5% of average since the March 1 forecasts, except for the Elbow River forecast which did not change. The March to September 2007 forecast volumes are 13 to 34% higher than those recorded during the same period last year, except 7% higher at the Spray Reservoir. The current forecasted volume for the Bow River at Calgary would rank 60th lowest in 91-years of record (1912-2001). March natural runoff volumes are ice affected and not yet available, but appear to be above average in the Highwood River and below average for the Elbow River. March volumes typically comprise a small portion of the March to September total.