Water Supply Outlook for Alberta

April 2002

Table 3a - Water Supply Forecast as of April 1, 2002 - Oldman River Basin (Natural Flows)

Volume Forecast for March 1 to September 30
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 2001 Volume as a % of Average
St. Mary River 662,000* 88 59-108 52 29/84 53
Belly River 216,000 88 56-110 51 26/84 70
Waterton River 559,000 85 50-99 43 24/84 60
Oldman River near Brocket 816,000 74 50-110 40 21/84 47
Oldman River at Lethbridge 2,332,000 78 49-106 42 22/84 49

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 1995

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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