Delineating aquifer management units in southern Alberta to support regulatory decisions on groundwater licensing

Southern Alberta’s water supply is experiencing increased demand across all water-use sectors due to economic and population growth; however, the region is prone to widespread drought and water shortages, and the Bow, Oldman and South Saskatchewan River basins are closed to new surface water allocations. To address future water availability challenges, the Government of Alberta is reviewing its water management strategy to improve access to water while maintaining high standards of water conservation and protection. Groundwater has been identified as a potential source of a reliable alternative water supply. The Alberta Geological Survey (AGS) is undertaking hydrogeological characterization, geological mapping and modeling of Neogene-Quaternary sediments and Cretaceous bedrock, and regional electromagnetic geophysical surveying in the southern Alberta to better understand groundwater availability and connected surface water resources. In addition to mapping geological and hydrogeological properties, the AGS will also delineate and classify aquifers. Approaches to aquifer delineation and classification in other jurisdictions are often not suitable for resource management in Alberta as they are either too large a scale or do not account for the (hydro)geological setting and water use patterns in Alberta. Therefore, we tailor our aquifer mapping to consider different geological and hydrogeological conditions and the scale intended for the application of groundwater management such as licensing, indicators, and thresholds. Aquifers will be mapped based on variations in geological properties such as lithology, sandiness, and/or permeability, as well as hydrogeological flow systems, water quality, and water use criteria. Qualitative, categorical, indicators such as vulnerability to contamination, water availability and demand, surface water connection, and data availability and confidence can be used to classify aquifers and prioritize those requiring further attention. Quantitative analyses within aquifers can be conducted to inventory groundwater availability, predict sustainability of aquifers and connected surface water, and allow for improved regulatory decisions on groundwater licensing.