Water Supply Outlook for Alberta

August 2008

Table 3b - Water Supply Forecast as of August 1, 2008 - Oldman River Basin (Natural Flows)

Volume Forecast for August 1 to September 30, 2008 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 2008 Volume as a % of Average Ranking (lowest to highest)
St. Mary River 94,700** 97 72-128 70 47/91 105*** 56/91
Belly River 32,500* 90 77-132 69 39/91 99*** 43/91
Waterton River 60,900* 98 77-129 66 55/91 112*** 62/91
Oldman River near Brocket 93,400* 87 70-116 64 48/91 98*** 46/91
Oldman River at Lethbridge 304,000* 91 67-120 61 47/91 103*** 61/91

*NOTE: The forecast shown is the March to September 2008 forecast minus the recorded volume to date

Click on the site Location to see the Water Supply Forecast graphically


** - This value is the natural volume and includes the U.S. share
*** - Recorded 2008 natural volumes are preliminary and subject to change
Average is calculated for the period 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 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