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The report advocates for the use of spatial targeting to maximize the water quality and climate adaptation benefits of water retention projects, such as wetlands and naturalized dams, in the Canadian Prairies. It highlights the PTMApp model and the necessity of high-resolution LiDAR-based digital elevation models (DEMs) to accurately map phosphorus loading and identify non-contributing areas. Using the Swan Lake study area as a demonstration, the document argues that strategic site selection improves cost-effectiveness and phosphorus interception, particularly during high-magnitude spring runoff events.

The report details a spatial targeting strategy for phosphorus reduction in the Canadian Prairies, using the Swan Lake study area as a pilot. It integrates the PTMApp model with HEC-HMS and HEC-RAS to account for regional hydrological specifics, such as spring runoff and non-contributing areas. Key findings highlight that default PTMApp settings may overestimate BMP efficiency during spring runoff and that high-quality land-use data is critical to avoid significant errors in nutrient load estimates. The report also discusses the practical application of these models for government and First Nations stakeholders, emphasizing the value of local knowledge and the need for compensation programs to encourage BMP adoption on high-value cropland.

The report argues that while water retention is a key climate adaptation tool in Manitoba, its effectiveness depends on strategic site selection, naturalized design, and long-term monitoring. It details the multi-dimensional benefits of water retention—including flood and drought risk reduction, water quality improvement, carbon sequestration, and biodiversity enhancement—and provides a three-step integrated framework for the province to assess storage needs, develop optimized solutions, and implement informed decision-making processes.