On August 23, 2024, Regulation 77/2024 was registered, introducing specific nutrient concentration and loading targets for Lake Winnipeg and its tributary rivers. This regulation is part of Manitoba’s commitment to water protection, addressing the critical issue of nutrient pollution in the region, which negatively impacts aquatic ecosystems and water quality. The regulation begins by defining key geographic areas: the Lake Winnipeg — north basin, marked by specific points from Willow Point light tower to Disbrowe Point; the Lake Winnipeg — south basin, delineated by a line from Grassy Narrows to Clements Point light tower, including the mouth of the Red River; and the Lake Winnipeg — narrows, which refers to the channel separating the north and south basins.

These definitions provide a foundational understanding of the regions targeted for nutrient regulation. The regulation sets explicit nutrient concentration targets for both basins of Lake Winnipeg, with a Total Phosphorus Concentration Target of 0.05 mg/L for both basins and the narrows, and a Total Nitrogen Concentration Target of 0.75 mg/L for all designated areas. These concentration targets are crucial for maintaining the health of Lake Winnipeg, as excessive phosphorus and nitrogen can lead to algal blooms, which diminish water quality and harm aquatic life.

In addition to concentration targets, the regulation specifies nutrient loading targets for several tributary rivers flowing into Lake Winnipeg, measured in tonnes per year. The targets include 60 tonnes/year of total phosphorus and 4,550 tonnes/year of total nitrogen for the Dauphin River (midway between Anama Bay and Gypsumville), 340 tonnes/year of total phosphorus and 8,960 tonnes/year of total nitrogen for the Saskatchewan River (at Grand Rapids), 1,050 tonnes/year of total phosphorus and 19,450 tonnes/year of total nitrogen for the Winnipeg River (at Pine Falls), and 2,800 tonnes/year of total phosphorus and 19,050 tonnes/year of total nitrogen for the Red River (at Selkirk). These loading targets are designed to control nutrient influx into Lake Winnipeg, mitigating the risks of eutrophication and promoting a healthier aquatic environment.

Regulation 77/2024 represents a significant step toward sustainable water management in Manitoba. By establishing clear, scientifically backed nutrient targets, the regulation aims to improve the water quality of Lake Winnipeg and its tributaries, protecting the diverse ecosystems that rely on this vital water source. The regulation reflects a proactive approach to combating nutrient pollution, a major contributor to environmental degradation in freshwater systems. The enforcement of these targets is expected to foster collaboration among stakeholders, including agricultural producers, municipalities, and environmental organizations.

In conclusion, the Nutrient Targets Regulation (M.R. 77/2024) under The Water Protection Act serves as a critical framework for addressing nutrient pollution in Lake Winnipeg and its tributaries. Through clearly defined concentration and loading targets, this regulation aims to protect and improve water quality, ensuring a sustainable future for the lake and its surrounding ecosystems.

Manitoba (77/2024) August 23, 2024