Water Supply Outlook for Alberta

May 2016

Water Supply Forecast as of May 1, 2016 - Oldman River Basin (Natural Flows)

Volume Forecast for May 1 to September 30, 2016 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-April 2016 Volume as a % of Average Ranking (lowest to highest)
St. Mary River 467,000** 79 68-95 58 17/99 143*** 79/99
Belly River 183,000* 88 81-96 74 26/99 157*** 95/99
Waterton River 370,000* 75 64-86 54 17/99 172*** 90/99
Oldman River near Brocket 538,000* 62 54-70 47 11/99 150*** 80/99
Oldman River at Lethbridge 1,595,000* 64 51-77 39 15/99 130*** 73/99

*NOTE: The forecast shown is the March to September 2016 forecast minus the recorded volume to date

** - This value is the natural volume and includes the U.S. share
*** - Recorded 2016 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