Water Supply Outlook for Alberta

July 2006

Table 4a - Water Supply Forecast as of July 1, 2006 - Oldman River Basin (Natural Flows)

Volume Forecast for March 1 to September 30, 2006
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-September 2005 Volume as a % of Average
St. Mary River 772,000* 104 97-111 93 52/91 77
Belly River 248,000 101 96-109 94 50/91 90
Waterton River 654,000 108 101-116 97 59/91 85
Oldman River near Brocket 971,000 89 85-101 83 37/91 132
Oldman River at Lethbridge 2,835,000 95 85-104 81 47/91 106

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

Click here to see the table containing the remaining forecast for the season along with the recorded volume to date

* - 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 reasonable minimum. Actual day to day streamflow conditions Jun vary throughout the season as a result of the effects of streamflow diversion and reservoir storage.

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