Water Supply Outlook for Alberta

February 2005

Table 3 - Water Supply Forecast as of February 1, 2005 - Oldman River Basin (Natural Flows)

Volume Forecast for March 1 to September 30, 2005
Locations Volume in dam3 Volume as a % of Average Probable Range as a % of Average Reasonable Minimum as % of Average Forecast Ranking (lowest to highest) Recorded March-September 2004 Volume as a % of Average
St. Mary River 570,000* 77 58-106 49 17/91 80
Belly River 192,000 78 64-105 55 18/91 92
Waterton River 470,000 78 59-109 49 19/91 76
Oldman River near Brocket 856,000 78 57-111 48 25/91 68
Oldman River at Lethbridge 2,161,000 72 53-105 44 20/91 69

Note: Click on the site Location to see the Water Supply Forecast graphically

* - This value is the natural volume and includes the U.S. share
Average is calculated for the March 1 to September 30 period from 1912 to 2001

NOTE: There is: a 50% chance that the actual natural flow will fall within the probable range given; a 25% chance that the actual flow will be less than the lower bound of the probable range given; and a 10% chance that the actual natural flow will be less than the reasonable minimum. Actual day to day streamflow conditions may vary throughout the season as a result of the effects of streamflow diversion and reservoir storage.

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