Blue green algae, or cyanobacteria, are microscopic organisms that thrive in nutrient-rich waters, forming toxic blooms that harm aquatic ecosystems, drinking water, and human health. In Ontario, blooms are common in warm, shallow lakes, driven by phosphorus and nitrogen runoff.  They produce toxins like microcystins, exceeding SDWA limits (>1.5 µg/L), posing risks to recreational waters and requiring immediate MECP reporting.  Canadian Shield Consultants addresses these issues to protect the Canadian Shield’s pristine lakes.