Water Supply Outlook for Alberta

April 2017

Water Supply Forecast as of April 1, 2017 - Oldman River Basin (Natural Flows)

Volume Forecast for April 1 to September 30, 2017 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 2017 Volume as a % of Average Ranking (lowest to highest)
St. Mary River 720,000** 112 103-127 95 55/99 267*** 96/99
Belly River 259,000* 155 107-127 99 69/99 236*** 96/99
Waterton River 607,000* 115 105-124 96 58/99 150*** 89/99
Oldman River near Brocket 1,072,000* 113 102-137 92 58/99 186*** 91/99
Oldman River at Lethbridge 3,159,000* 117 105-128 95 66/99 190*** 88/99

*NOTE: The forecast shown is the March to September 2017 forecast minus the recorded volume to date

** - This value is the natural volume and includes the U.S. share
*** - Recorded 2017 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