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Assumptions about irrigation-agriculture expansion called into question

Posted on March 5, 2024 by Ryan Dahlman

A recent article in the Lethbridge Herald (Feb. 14) regarding designation of an AgriFood Processing Zone contains assertions by UCP MLA Grant Hunter to Lethbridge County Council that irrigation districts are making decisions about expanding by 300,000 acres and that more water storage is being built, paid for by government and ratepayers, to support that expansion. I suggest announcements of expanded irrigation and reservoirs to support more water capture and diversion at public expense are untethered from reality, reasonableness and public scrutiny. 

The current drought throughout the Oldman River Basin is characterized by mountain snowpack well below long-term average, streams and rivers at minimum flows for aquatic life, and reservoirs, on-stream and off-stream, well below normal levels for this time of year. Models of climate change suggest more frequent and prolonged drought is our future. There is not enough water to fill existing reservoirs with just two years of below average mountain snowpack and precipitation. Is it realistic to build, at great public expense, more storage capacity that will remain unfilled in many years, provide more surface for water loss through evaporation and increase stress on rivers? 

Irrigated area in the Oldman basin has increased at least 16 per cent since restrictions on water allocation were first implemented by government three decades ago. Another 15 per cent or more expansion is proposed, as indicated by MLA Hunter. Irrigation districts, supported by government, justify expansion within their current water licences based on calculations of water saved through improvements in irrigation infrastructure such as more efficient pivots on farms and replacing canals with pipelines. A growing body of research concludes that irrigation water use in semi-arid regions has increased despite claims of limits to allocation and improvements in efficiency.  In a ‘paradox of irrigation efficiency’ more water is withdrawn and applied as irrigators increase crop area and switch to higher-value, more water-intensive crops (e.g. potatoes, corn, hay). Summer flow in the Oldman River is already reduced by approximately 60 per cent from natural levels in its lower reaches. Increased evapotranspiration from warming climate will place further stress on the Oldman River and its tributaries below major dams and diversions. Is irrigation expansion worth the increased risk to our rivers’ water quality, fish and cottonwood forests, not to mention other water users? 

Two-thirds of the Oldman River’s natural flow in an average year is allocated for irrigation agriculture comprising eighty-seven percent of total volume of water licences. Five percent is licenced for industrial use and only two percent for municipalities. Eight irrigation districts hold the largest, most senior water licences dating back to 1899. Because of historical over-allocation, the basin is closed to new water licences. As river flow declines, the proportion of water used for irrigation agriculture will only increase. Rights to water, our most essential and limiting public resource, will be in more demand with population growth, economic diversification and settlement of indigenous rights. Is it reasonable to entrench one sector’s stranglehold on water rights and deny options to future generations for a diverse and environmentally sustainable economy?  

MLA Hunter’s presumptions about irrigation expansion and increased storage paid for by government are premature and ignore the established need for environmental impact assessment and review by the Natural Resources Conservation Board to determine if the proposed projects are in the public interest. There has yet to be a full evaluation of costs and benefits. Are there implications for communities and land use in our headwaters? Are we witnessing undue influence by the agrifood industry over important land use and water management decisions that have repercussions for all of us who call the Oldman River basin home? It is reasonable and realistic to expect public scrutiny of these matters which MLA Hunter considers a done deal. 

Cheryl Bradley, Lethbridge

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