Water Supply Outlook for Alberta

May 2004

Table 3b - Water Supply Forecast as of May 1, 2004 - Oldman River Basin (Natural Flows)

Volume Forecast for May 1 to September 30, 2004 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 2004 Volume as a % of Average Ranking (lowest to highest)
St. Mary River 450,000** 68 53-100 48 16/91 103*** 54/91
Belly River 154,000* 69 62-99 53 10/91 119*** 62/91
Waterton River 413,000* 75 59-111 51 20/91 75*** 42/91
Oldman River near Brocket 693,000* 72 55-114 40 23/91 92*** 53/91
Oldman River at Lethbridge 1,770,000* 67 51-98 41 19/91 82*** 37/91

*NOTE: The forecast shown is the March to September 2004 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 2004 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.


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