Water Supply Outlook for Alberta

August 2008

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

Volume Forecast for March 1 to September 30, 2008
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 2007 Volume as a % of Average
St. Mary River 790,000* 106 103-110 102 60/91 n/a**
Belly River 239,000 98 96-104 94 43/91 n/a**
Waterton River 669,000 110 108-113 107 63/91 n/a**
Oldman River near Brocket 1,056,000 97 95-100 95 56/91 n/a**
Oldman River at Lethbridge 3,020,000 101 98-105 96 51/91 n/a**

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


* - This value is the natural volume and includes the U.S. share
** The recorded March-September 2007 volumes will be published in the next Water Supply Outlook Report.

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 may vary throughout the season as a result of the effects of streamflow diversion and reservoir storage.

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