Phosphorus is poisoning the lake.

Phosphorus and nitrogen enter Lake Winnipeg through municipal and industrial wastewater, agricultural runoff, and air pollution. The Red River carries more of these nutrients into the lake than any other source.

The highest concentrations of phosphorus and nitrogen are found in the south basin, near the inflow from the Red River. Levels decline as the water flows north — meaning the Red is the single biggest contributor to the lake's nutrient overload.

Excess nutrients fuel increasingly large, frequent, and potentially toxic algal blooms. These blooms deplete oxygen, kill fish, produce toxins that make the water unsafe for swimming, and threaten the lake's commercial fishery — one of the largest in western Canada. Lake Winnipeg has been called the "most threatened lake of the year" by the Global Nature Fund in 2013, and phosphorus levels are now approaching a point that could be dangerous for human health.

Every year, the algal blooms grow larger. Every year, the phosphorus loading exceeds the targets set by the provinces and the federal government. The lake receives roughly 8,000 tonnes of phosphorus per year — far more than it can process. According to the State of Lake Winnipeg report (2020), phosphorus levels have not meaningfully declined since reduction targets were set.

This is not a future problem. It is a current one. The south basin of Lake Winnipeg regularly produces toxic cyanobacteria blooms large enough to be visible from satellite imagery.

Red River Revival's primary focus is macro-debris — the cars, tires, and garbage sitting in the river. But debris and nutrient loading are not separate problems. A tire leaching 6PPD-quinone into phosphorus-heavy water is compounding the damage. A car leaking motor oil into a river already choking on algae is making a bad situation worse.

We can't fix agricultural runoff on our own. But we can pull the things out of the river that make the nutrient problem worse, and we can push for the policy changes that address the source.

Learn about our debris removal work →