Important Notice to Irrigators: June Water Supply Update

Jun 28, 2024

Dear Irrigators,

Below is the most recent information regarding our water supply situation:

The Akamina and Many Glacier Snow Pillows both show no Snow Water Equivalent (SWE) at the elevation of the pillows. However, there are reports that some snow has yet to run off at higher elevations.

Flat Top Snow Pillow continues to drop off through June and is following the lower quartile for snowpack.

Alberta Agriculture & Irrigation (AGI) continued releasing from the Waterton Reservoir and diverting flows at the Belly River Diversion adding to the storage in the St. Mary Reservoir which is 85% full; operators are maintaining their release down the river as needed.

The St. Mary Headworks Reservoirs, made up of the Waterton, St. Mary, and Milk River Ridge reservoirs, are up from 379,000 ac-ft on June 28, 2023, to 429,000 ac-ft or 92% Full Supply Limit (FSL) as of June 28, 2024.

SMRID Reservoirs have made minor gains in storage since our last update in May and now contain 214,000 acre-feet of storage, or 67% of our Irrigation FSL, compared to 260,000 acre-feet, or 82% Irrigation FSL in June 2023.

To date, SMRID has not received any significant additional water from Montana following the June 17th siphon-failure. We are still receiving our allotted volume, but it is not more than our apportioned share. Lake Sherburne in Montana is capturing water upstream of the siphon failure and is currently sitting at 85% storage. Once Lake Sherburne is full, some water will be released downstream into the St. Mary River.


Based on the above information and the latest Irrigation Water Supply Forecast supplied by Alberta Agriculture and Irrigation (AGI) and reservoir storage forecast modeling performed by Alberta Environment and Protected Areas (AEPA), the Board of Directors has raised the water allocation to 9 inches at the farm gate for the 2024 irrigation season, effective immediately.

We will continue to review the water supply situation and keep you informed of future developments.

Please continue to irrigate responsibly as we are still under the Water Sharing Memorandum of Understanding within the South Saskatchewan tributaries sub-basin.


David Westwood
General Manager
St. Mary River Irrigation District