Bow River Basin - Water Supply Forecasts

As of May 1, 2004, March to September 2004 natural runoff volumes are forecast to be below-average in the Elbow and Highwood Rivers and at the Cascade Reservoir, and below-average to much-below-average at Calgary, Banff, Kananaskis and the Spray Reservoir (Table 4a). Current runoff volume forecasts range from 72 to 88% of average, 1 to 5% lower than last month's forecasted volumes. Current March to September 2004 volume forecasts are 0 to 5% higher than runoff volumes recorded during the same period last year, except for the Cascade Reservoir, which is forecast to receive 10% less volume than last year. Current forecasted volumes for the March to September 2004 period for the Bow River at Calgary would rank 23rd lowest in 91 years of record (1912-2001).
 

The first two months of the forecast period have been completed, with March-April 2004 recorded runoff volumes ranging from 55 to 121% of average. Bow River basin forecast locations recorded below-average to much-below-average runoff so far, except for the Kananaskis River which was average, and at Banff and in the Spray River, which recorded above-average and much-above-average volumes, respectively. Recorded volume data is preliminary, due to ice effects, and is subject to change. Current volumes represent approximately 5 to 10% of the volumes forecasted. forecast, which is the March to September 2004 forecast minus the recorded volume to date, is available in Table 4b.