Water Supply Outlook for Alberta

May 2009

Water Supply Forecast as of May 1, 2009 - Oldman River Basin (Natural Flows)

Volume Forecast for March 1 to September 30, 2009
Locations Volume in dam3 Volume as a % of Average Probable Range as a % of Average Potential Minimum as % of Average Forecast Ranking (lowest to highest) Recorded March-September 2008 Volume as a % of Average
St. Mary River 644,000* 86 71-103 59 25/91 111
Belly River 222,000 91 77-103 72 29/91 96
Waterton River 553,000 91 72-104 63 33/91 108
Oldman River near Brocket 954,000 87 72-108 59 37/91 97
Oldman River at Lethbridge 2,499,000 84 65-103 55 29/91 102

 

* - 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 potential 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