Water Supply Outlook March 2015

Updated: March 5, 2015

Mountain runoff forecasts (natural volumes for March to September 2015)

Milk River basin
  • Average
Oldman River basin
  • Below average
Bow River basin
  • Below average for the Bow River at Banff, Lake Minnewanka, Elbow River and Highwood River
  • Average for Kananaskis River and Bow River at Calgary
  • Above average for Spray River near Banff
Red Deer River basin
  • Below average
North Saskatchewan River basin
  • Below average for Lake Abraham (Bighorn Reservoir)
  • Average for Brazeau Reservoir and North Saskatchewan River at Edmonton

Precipitation can have a major impact on water supply between now and the end of September. The forecasts above assume that precipitation over the remainder of the winter period and through the summer will be normal. The range of possible precipitation scenarios is large however, and as a result, probable range forecasts and a minimal precipitation forecast of natural runoff volume are also provided for each individual basin. Since more information becomes known over time, forecast ranges will narrow. Streamflow volume forecasts are updated monthly from February to May, and again in July.

Check our Forecaster's Comments throughout the month for updated information regarding runoff conditions.

Mountain snowpack

Snow accumulations measured in the mountains as of March 1, 2015:

  • Oldman River basin: Ranging from much below average to below average (32% of average at West Castle to 81% of average at Allison Pass). South Racehorse Creek was the only site with average conditions.
  • Bow River basin: Ranging from much below average (76% of average at Little Elbow Summit) to average (106% of average at Mist Creek).
  • Red Deer, North Saskatchewan, Athabasca River basins:

    Highly variable in the North Saskatchewan River basin, much below average (71% of average at Limestone Ridge) to much above average (140% of average at Brown Creek).

    Much above average in the Athabasca River basin (125-166% of average).

    Below average to above average in the Red Deer River basin (79% of average at McConnell Creek and 110% of average at Gable Mountain).

  • Upper Peace River basin in British Columbia: as indicated in British Columbia's Snow Survey and Water Supply Bulletin

Mountain snowpack is an important source of water supply to reservoirs in the spring. Accumulation at this time of year typically accounts for nearly three-quarters of the seasonal total.

Plains Spring Snowmelt Runoff Forecasts

Conditions are variable across the province, please refer to the map in the Plains Runoff Forecast section of our Maps and Data Summaries webpage.

Plains snowpack

  • Map of Snow course measurements taken at the end of February and the beginning of March in many areas of central and northern Alberta. Cypress Hills snow measurements were taken in mid-February.
  • Environment Canada map of satellite estimation of plains snow water equivalent (SWE) as of March 1, 2015 is shown here.
  • Alberta Agriculture publishes maps of modelled plains snow accumulations and accumulations as compared to normal.


Contoured maps of precipitation amounts and as a percent of normal for the past month and for current and recent seasons are available here. Maps of precipitation amounts for the most recent day, week and month to date are available here.

Soil Moisture

Alberta Agriculture models soil moisture for non-mountainous, agricultural areas of Alberta. Modelled soil moisture compared to average as of February 15, 2015 is available here.

Long Lead Precipitation Outlooks

Environment Canada (issued on February 28, 2015): Precipitation is forecast to be above normal and temperatures are forecast to be below normal in southeastern Alberta for the March through May 2015 period.

National Oceanic and Atmospheric Administration (NOAA) (issued on February 19, 2015): An equal chance of below normal, normal or above normal precipitation and above normal temperatures in the south of Alberta for March through May 2015.

Climate indicators: The NOAA reported on February 5, 2015 that ENSO Alert System Status was at El Niño Watch. There is an approximately 50-60% chance of El Niño within the late Northern Hemisphere winter and early spring, with ENSO-neutral slightly favoured thereafter.

Note that forecasting weather for such a long time period into the future is very difficult, and so the historical accuracy has been variable, dependent on location and time period, and is often low, more so for precipitation than temperature. Environment Canada provides an assessment of their forecast method's historical accuracy on their website.

Reservoir storage

Water storage volumes in the major irrigation and hydroelectric reservoirs of the Milk, Oldman, Bow, Red Deer North Saskatchewan, and Athabasca River basins is updated each weekday and is available in the Provincial Reservoir Storage Summary.


Background information on the Water Supply Outlook is available in Frequently Asked Questions

Media Contact:
Communications Division, Alberta Environment
Phone: (780) 427-6267