Canada
About this guideline ▾
Canada has three sets of federal water quality guidelines:
the Canadian Council of Ministers of the Environment (CCME) Canadian Water Quality Guidelines,
Health Canada's Guidelines for Canadian Recreational Water Quality, and
Environment and Climate Change Canada's Federal Environmental Quality Guidelines (FEQGs).
We use these on the Water Rangers platform to help interpret monitoring data.
Nitrate
Freshwater
| Range | Level | Impact |
|---|---|---|
| ≤ 12.0 mg/L | Met guideline | Long-term freshwater guideline for aquatic life |
| ≥ 13.0 mg/L | Exceeds chronic guideline | Chronic exceedance stresses fish and invertebrates |
| ≥ 550.0 mg/L | Exceeds acute guideline | Acute exceedances of this short-term threshold are lethal to most species |
Nitrate is a naturally occurring form of nitrogen, but agricultural fertilizer, sewage discharge, and urban runoff can push concentrations well above natural levels, directly harming fish and invertebrates at high concentrations. When levels rise too high, nitrate interferes with the ability of aquatic organisms to carry oxygen in their blood, affecting growth, reproduction, and survival. The CCME sets the long-term freshwater guideline at 13 mg/L and the short-term guideline at 550 mg/L, measured as the nitrate ion.
https://ccme.ca/en/chemical/140