The sheer scale of the projects is the core concern for Canadian officials and environmental groups. The combined 37,500 milking cows would more than quadruple North Dakota’s current herd of $\approx$ 8,900 head, nearly matching the total cow inventory of the entire province of Manitoba ($\approx$ 45,000 cows across 240 farms). Given that the operations are located within 1.5 miles of the Red River or its tributaries, the massive volume of manure is raising alarms about excess phosphorus and nitrogen runoff into Lake Winnipeg.

The nutrient loading issue is critical because Lake Winnipeg is already considered “at-risk.” Although the Red River contributes only $\approx$ 15% of the lake’s water flow, a late 2024 provincial report noted it carries the largest load of nutrients among all major tributaries. Existing targets for the Red River, approved by Canada and the U.S. in late 2022, called for a significant 45% reduction from current levels, aiming for 1,400 tonnes of phosphorus annually. However, the 2024 report showed an average of 2,500 tonnes of phosphorus per year crossing the border.

Environmental advocates, including the Manitoba Eco-Network, have underscored the infrastructure challenge, pointing out that waste will be stored in manure lagoons covering an area equivalent to 52 Canadian football fields without municipal wastewater treatment. The subsequent spreading of this manure slurry on agricultural fields as fertilizer increases the risk of nutrient accumulation in the shared river basin. Concerns also extend beyond nutrients to potential pollution from antibiotics, hormones, bacteria, and heavy metals into the international watershed.