The location of the Experimental Lakes Area was intentionally chosen in a remote location of Northwestern Ontario, where most human activities are limited. The remote location limits the number of stressors that threaten the water quality and biota of these lakes. At our lakes the two biggest threats are climate change and the long-range deposition of pollutants.

When it comes to lakes around the world more broadly, eutrophication and harmful algal blooms resulting from excessive nutrient inputs, in particular phosphorus. Algal blooms are the leading cause of the degradation of freshwater ecosystems globally, and they are very expensive to fix once they become a problem. The best approach is to determine which factors drive blooms and work to prevent those through policy (e.g., regulations on wastewater effluent, or runoff from agriculture).

There are also many potentially harmful chemicals in wastewaters, that derive from a growing list of chemicals that we, the public, use in our everyday lives. Some of these chemicals do not naturally break down and are potentially toxic to plants and animals. These chemicals include microplastics, mercury, road salt, plastics, and the chemical released during oil spills.

Habitat destruction from flow modification (dams, irrigation, etc.) also has an impact, as does the physical alteration of shorelines.

And, as always, invasive species (such as zebra mussels in Lake Winnipeg) pose a risk to our lakes worldwide.