Water Supply Outlook for Alberta

May 2005

Table 3 - Water Supply Forecast as of May 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 532,000* 71 59-94 52 17/91 80
Belly River 185,000 76 66-98 58 14/91 92
Waterton River 429,000 71 60-95 53 17/91 76
Oldman River near Brocket 759,000 70 58-102 53 23/91 68
Oldman River at Lethbridge 1,972,000 66 53-95 48 17/91 69

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

Click here to see the table containing the remaining forecast for the season along with the recorded volume to date

* - 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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