Water Supply Outlook for Alberta

April 2006

Mountain Water Supply Forecast Summary

As of April 1, 2006, natural runoff volumes are forecast to be below average for the Milk, Red Deer and North Saskatchewan River basins for the March to September 2006 period. In the Bow River basin, natural runoff volumes ranging from below average to average are expected. In the Oldman River basin, natural runoff volumes are forecast to be average (Table 1). Forecasted volumes have decreased slightly since March 1 in most basins, due to much below normal precipitation in most mountain areas during March, however they have increased slightly in the Waterton and Kananaskis River basins and for the Oldman River at Brocket.

Snow accumulations in the mountains as of April 1, 2006 generally improve moving from north to south and at higher elevations. Measured snowpacks are generally much below average in the Athabasca, Red Deer and North Saskatchewan River basins, below average in the Highwood and upper Bow River basins, below average to average in the Kananaskis and Elbow River basins, and average to above average in the Oldman River basin. Snowpack at lower elevations of many of these basins however is below average. Lower elevation basins, such as the Milk and Belly River basins, have lesser snowpack as well.

The first month of the forecast period has been completed, with March 2006 recorded natural runoff volumes being generally above average in the Milk, Oldman, and Bow River basins, average in the North Saskatchewan River basin, and below average to average in the Red Deer River basin. Warm temperatures during March resulted in early melting of plains and foothills snowpack.

Water Survey of Canada has updated their runoff volume data for 2005. Natural volumes calculated based on this data is available in (Table 2). This 2005 data is referenced in the basin forecast tables of this report.

Forecasts assume that precipitation over the summer period will be normal. Precipitation will have a major impact on the summer water supply forecast between now and the end of September. Streamflow volume forecasts will be updated monthly until mid-summer. Check our Forecaster's Comments throughout the month for updated information regarding runoff conditions.

For technical enquires about this web page please contact Alberta Environment - Environmental Management Water Management Operations Branch at AENV-WebWS@gov.ab.ca