Final Terms of Reference for Snake Lake Reservoir Expansion

July 24, 2024

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• Areas of Concern
• Grasslands
• Issues

The final terms of reference for the Snake Lake Reservoir Expansion project have been published, and while they address some of AWA’s concerns, it still lacks information that is needed to produce a thorough and informative environmental impact assessment.

Terms of reference outline the goals of an environmental impact assessment (EIA) and essentially define what information will be included and how this will be collected. Environmental impact assessments need to examine all the consequences of a project, and be used to make an informed, science-based decision on whether a project should be allowed to proceed. The final terms of reference for the Snake Lake reservoir expansion environmental assessment, although now stronger with the amendments, still falls short of providing the full picture.  

Snake Lake is an existing reservoir covering 320 hectares that can store 18.4 million cubic meters of water. The proposed expansion would more than triple this reservoir to cover 1,100 hectares and store 86 million cubic meters. Most of this expansion would occur on native grassland – 84 percent of the sites sampled were identified as native grassland communities. This expansion is only one of many projects announced as part of the $933 million Alberta Irrigation Modernization Program.  

Read about AWA’s previous concerns here.

AWA was pleased to see amendments to the terms of reference that addressed the impact on native grasslands and the potential to worsen climate change and drought. According to the final terms, the significance of and changes to native grasslands, both direct and indirect, will need to be mapped in the environmental assessment, and the cumulative effects of the project will be explicitly discussed. The environmental assessment will require greenhouse gas emissions – often released by reservoirs – to be described, and instead of focusing only on the benefits of the project for climate change, the consequences will also need to be discussed. In the socio-economic impacts, the economic costs of native grasslands and biodiversity will also need to be considered, although the economic impacts of wetland loss and climate change are not mentioned.  

These changes provide a stronger assessment of the environmental costs for the Snake Lake reservoir expansion project, however, there are still weaknesses to the environmental assessment. For instance, even though they are seeking more information on avoiding important habitats and wildlife impacts, there is no discussion of alternatives to the proposed project that would cause less damage. There is no mention of other ways to store and use water, such as investing into wetlands, grasslands, and riparian (or riverbank) ecosystems that can help to slow water loss and keep water in the ground longer. These measures would not only help with drought tolerance, they provide habitat for wildlife. 

Assessing cumulative effects, a requirement AWA has long argued for, is explicitly mentioned for water quality and quantity, as well as for aquatic resources, native grasslands, wetlands, wildlife, and species of concern. Although we celebrate the integration of cumulative effects, the overall impact of this project is not assessed with all other projects in the Alberta Irrigation Modernization Program, and the effect of expanding irrigation, one of the main reasons for expanding Snake Lake Reservoir, is not acknowledged past a discussion of how new irrigated parcels will be added. For cumulative effects to be effectively managed, we need to be assessing and planning for all projects that could affect a region. Detailed regional land use plans that protect the environment need to be completed and followed.  

In particular, it’s unclear where the water needed to support expanded irrigation will come from, as the South Saskatchewan River Basin has been closed to new water licenses since 2006. According to the project background the proposed Snake Lake reservoir expansion “will allow more water to remain in the Bow River, helping to maintain instream flow needs” by storing water and supplying agriculture and other water needs during extended droughts. However, reservoirs have not historically helped maintain instream flow needs. Following the Water Act, reservoirs are used to first fulfill existing water licenses, often leaving very little to help maintain river health, as was seen during the last drought.  

Instream flow needs (IFNs) refer to the water quality and quantity needed for healthy aquatic environments. In Alberta, IFNs are rarely met, as the Alberta government uses a less stringent threshold known as water conservation objectives (WCOs). WCOs are the minimum quantity and quality of water that must remain in a given basin under the Water Act, but unlike IFNs, are not based on scientific evidence, and typically do not retain enough water to prevent ecosystem degradation. Increasing irrigation will necessarily include using more water, and building reservoirs will not solve a water crisis if the rivers are dry.  

Drought tolerance is vital for southern Alberta agriculture, although expanding irrigation and the Snake Lake reservoir could have devastating consequences for river health and native ecosystems.