Working to strengthen Alberta’s irrigation districts and water supply

Posted on March 13, 2025 by Sunny South News

By Kristine Jean
Sunny South News

The time to act and prepare Alberta’s irrigation districts and water supply, is now. 

It’s a message that distinguished professor at the University of Saskatchewan, John Pomeroy shared with farmers, industry, academic leaders and government representatives during the 2025 Irrigated Crop Production Update in Lethbridge at the end of January.  

“I think it’s crucial to get it out now and for individual farmers to hear it,” said Pomeroy. “For many, this is a future beyond our lifetimes but it’s our children’s lifetime and we have to start getting those farms on a basis so they can make it through this century and to prosper, for the whole region.” 

Pomeroy is a global expert on climate change in cold regions and is an elected representative to the United Nations Water and Climate Coalition steering committee and is the UNESCO chair in Mountain Water Sustainability. 

He is also Canada research chair in water resources and climate change at the University of Saskatchewan and is director of the Global Water Futures program, and holds several other distinctions.  

In his presentation, Pomeroy focused on the impact that climate change is having on Alberta’s water supply and the availability of future water for the province’s irrigation districts. 

“As climate change carries on, by mid-century the temperatures around Lethbridge will be up on average about two (to) three degrees from what they were in the late 1800’s and by the end of the century, five to six or even seven degrees depending on how greenhouse gas emissions carry on,” said Pomeroy, in a post-presentation interview. “What’s interesting is that overall, precipitation will increase, rainfall will increase in particular, but a lot of that will be in the spring and in the winter and so our summers could be quite a lot drier than they are now.” 

Those hotter, drier summers will pose a challenge for dryland farming, he noted, making it less viable than it is now and pointed out the direct impact climate change could have on irrigation districts in southern Alberta.

  “For irrigated agriculture, the irrigation demand will increase because there’ll be more water needed to be applied to keep crops growing,” he said, adding there will also be changes in stream flow out of the mountains. “Mountain glaciers will have melted away by then and mountain snow packs will be much lower, so we’ll be dependent on mountain rain and that’s more variable and less dependable.” 

Pomeroy explained while there will be years when there’s lots of rain in the mountains and things look “pretty good” with lots of stream flow for irrigation, there will be other years when there’s less. These changes are perhaps “starting to show up now” and will be seen by mid-century with the most extreme impacts felt by the end of the century. 

“Stream flow will be coming more than a month earlier than it does now and summer flows could be less than half of what they are now,” said Pomeroy. “Overall flows (are) likely to be up a bit but a lot of that over the winter and spring.” 

Despite several challenges and variable factors facing southern Alberta and its irrigation districts, Pomeroy said there are ways to mitigate that impact and things that farmers can do to help alleviate the stress of climate change – both in the short and long-term.  

“Individual irrigators need to continue to improve their efficiency of irrigation and make sure that the crops they are choosing to grow have less water demand and can get through these drier periods,” said Pomeroy. “Also ones that can take advantage of the extra heat that we expect (is) coming and that may in fact increase the variety of crops that can be grown here to the benefit of some.” 

He said irrigation districts also have to examine their water management very carefully, including water storage. 

“Make sure that winter flows and spring streams flows are stored and made available for irrigators,” he said. “They’ll have to look at operating the existing control structures that we have, existing reservoirs, but also may have to consider increasing storage, either through temporary ground water storage or using mountain wetlands or even looking at increasing reservoir size or number in different areas.”           

It’s the variability and the shifting timing of stream flows that will present the biggest challenges for southern Alberta farmers, he noted. 

“In particular we’ll see droughts that are longer and twice as frequent and more severe and in between that flooded periods, where we have more multiple-day rainstorm events and severe flooding,” said Pomeroy. “We’ll be bouncing from one to the other and so we have to manage that. We have to smooth it out and the way you smooth it out is by storing the water.”