February Water Supply Outlook forecasts normal to above normal river volumes this summer. Photo by Stephen Strand
This summer’s river volumes are forecasted to be normal to above normal.
The February Water Supply Outlook forecasts are predicting normal to above normal March to September river volumes in the Milk, Oldman, Bow, Red Deer, and North Saskatchewan River basins.
Not only that, but these volumes are predicted to be either above or well above the river volumes observed in 2025.
Also, the basin wide storage for large reservoirs is normal to above normal in the Oldman and South Saskatchewan River basins, meanwhile the Red Deer and Bow River basins are below normal to normal.
While the river volumes are expected to be normal or above normal, winter precipitation in southern and central Alberta has ranged between below normal to above normal.
Precipitation can have major impacts on the water supply between now and autumn, but these forecasts assume that precipitation levels will be normal.
As part of the Mountain Runoff Forecast, both the Bow River and Oldman River Basins are normal to above normal.
While the Mountain Runoff Forecast is used as a seasonal decision-making tool, it is not intended to guide day-to-day operations.
These forecasts are statistical regressions between predictors and the estimated monthly natural streamflow at select locations from March to September.
The natural flow volumes used in these regressions are official historical natural flow volumes, which are calculated by the Environment and Protected Areas’ regional hydrologists.
As part of these calculations, they account for reservoir operations, precipitation/evaporation at the reservoirs, and all of the documented withdrawals and diversions.
The predictors include snow courses surveyed near the beginning of the month, snow pillow values on the first of the month, accumulated winter precipitation at stations located throughout the forecast basing, and fall flow volumes for the 30-year normal period from 1981 to 2009.
As part of this Water Supply Outlook, they surveyed twenty-nine mountain snowpacks around the beginning of February, and of the 20 sites that have more than 20 years of historical records, 16 had snowpack conditions that were either above normal or much above normal.
The Oldman River Basin is much below normal to above normal. Ranging from 45 per cent at Westcastle II to 111 per cent at Gardiner Creek. On average, these snowpack sites average 44 mm higher than last year.
The Bow River Basin is above normal to much above normal, ranging from 11 per cent tat Mount Odlum to 163 per cent at Pipestone Upper. On average 172 mm higher that last year.
To read the full Water Supply Outlook, click here.
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