Mountain Water Supply Forecast Summary

For July through September 2006, natural runoff volumes are forecast to be average in the Oldman River basin, below average to average in the Bow River basin, and below average in the Milk, Red Deer, and North Saskatchewan River basins.

Wet soils due to last year's heavy rains have dryed somewhat this year, but soil moisture is still near average in most southern mountain and foothill areas, and continues to provide good potential for runoff from rainfall that may occur during the remainder of this summer.

Natural runoff volumes during March through June 2006 have been near average in the Oldman and Bow River basins. Natural runoff volumes thus far have been below average in the Highwood, Milk, Red Deer, and North Saskatchewan River basins. Exceptions include inflows to the Waterton, Spray Lakes and Bighorn Reservoirs, which ranged from above to much above average, and to the Brazeau Reservoir, which was much below average.

Total natural runoff volumes for the water year (March to September 2006) are expected to range from below average to average in most forecasted areas(Table 1).

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 March - September 2006 forecast tables of this report.

Future precipitation could have a major impact on water supply forecasts between now and the end of September. Streamflow volume forecasts will be updated monthly until September. Check our Forecaster's Comments throughout the month for updated information regarding runoff conditions.