Ontario

Ammonia occurs naturally when organic matter breaks down, but also enters waterways through sewage, agricultural runoff, and industrial discharge. The un-ionized form is the most harmful, passing directly through cell membranes and damaging the gills and kidneys of fish and invertebrates. The Canadian Council of Ministers of the Environment (CCME) sets the long-term freshwater guideline at 0.019 mg/L.

Chloride guidelines are based on those set by the Canadian Council of Ministers of the Environment (CCME) to protect aquatic life.

View the chloride guideline

Chlorine is not naturally occurring. It is widely used to disinfect drinking water and swimming pools, but even tiny amounts can damage the gills of fish and harm the invertebrates that healthy aquatic ecosystems depend on. It enters waterways through treated wastewater, industrial discharge, and everyday activities like draining a pool or washing a car near a storm drain. The Canadian Council of Ministers of the Environment (CCME) sets the long-term freshwater guideline at 0.5 micrograms per litre (µg/L).

Chlorine is widely used to disinfect drinking water and swimming pools, but even tiny amounts can damage the gills of fish and harm the invertebrates that healthy aquatic ecosystems depend on. It enters waterways through treated wastewater, industrial discharge, and everyday activities like draining a pool or washing a car near a storm drain. The Canadian Council of Ministers of the Environment (CCME) sets the long-term marine water guideline at 0.5 micrograms per litre (µg/L).

E. coli is a bacterium found in the intestines of humans and warm-blooded animals, used as an indicator of fecal contamination because its presence signals that water may also contain harmful bacteria, viruses, and parasites. When levels are elevated, swimmers risk gastrointestinal illness and other infections. Health Canada's Guidelines for Canadian Recreational Water Quality set a Beach Action Value of 235 CFU/100 mL for single samples, above which swimming advisories should be considered, and a geometric mean of 126 CFU/100 mL for assessing longer-term water quality trends.

Enterococci are bacteria found in the intestines of humans and warm-blooded animals, recommended by Health Canada as a fecal indicator for both freshwater and marine recreational water monitoring, as their presence signals potential harmful pathogens. When levels are elevated, swimmers risk gastrointestinal illness and other infections. Health Canada's Guidelines for Canadian Recreational Water Quality set a Beach Action Value of 70 CFU/100 mL (culture-based) or 1000 CCE/100 mL (PCR-based), with a geometric mean of 35 CFU/100 mL or 470 CCE/100 mL for longer-term trend assessment.

Enterococci are bacteria found in the intestines of humans and warm-blooded animals, recommended by Health Canada as a fecal indicator for both freshwater and marine recreational water monitoring, as their presence signals potential harmful pathogens. When levels are elevated, swimmers risk gastrointestinal illness and other infections. Health Canada's Guidelines for Canadian Recreational Water Quality set a Beach Action Value of 70 CFU/100 mL (culture-based) or 1000 CCE/100 mL (PCR-based), with a geometric mean of 35 CFU/100 mL or 470 CCE/100 mL for longer-term trend assessment.

pH guidelines are based on those set by the Canadian Council of Ministers of the Environment (CCME) to protect aquatic life.

View the pH guideline