Water Supply Outlook for Alberta

August 2015

Water Supply Forecast as of August 1, 2015 - Oldman River Basin (Natural Flows)

Volume Forecast for August 1 to September 30, 2015 Year to date
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-July 2015 Volume as a % of Average Ranking (lowest to highest)
St. Mary River 53,000** 65 39-92 15 8/99 98*** 38/99
Belly River 24,000* 71 59-83 48 11/99 103*** 48/99
Waterton River 35,400* 65 50-95 36 15/99 99*** 37/99
Oldman River near Brocket 70,500* 70 43-97 18 26/99 91*** 33/99
Oldman River at Lethbridge 204,000* 65 50-80 36 18/99 88*** 36/99

*NOTE: The forecast shown is the March to September 2015 forecast minus the recorded volume to date

** - This value is the natural volume and includes the U.S. share
*** - Recorded 2015 natural volumes are preliminary and subject to change
Average is calculated for the March 1 to September 30 period 1981 to 2009

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