Water Supply Outlook for Alberta

August 2002

Table 3a - Water Supply Forecast as of August 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 1,182,000* 157 153-163 151 83/84 53
Belly River 384,000 157 153-162 148 83/84 70
Waterton River 977,000 148 144-152 141 81/84 60
Oldman River near Brocket 1,622,000 147 143-151 142 75/84 47
Oldman River at Lethbridge 4,311,000 145 141-155 139 77/84 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.


For technical enquires about this web page please contact Alberta Environment - Environmental Management Water Management Operations Branch at AENV-WebWS@gov.ab.ca