This thematic layer represents the characterization of the hardness of surface water in Quebec. The hardness is presented according to the medians calculated from the concentrations of calcium and magnesium ions in seven classes.
Water hardness influences the toxicity of certain metals, including barium, beryllium, cadmium, chromium, copper, manganese, nickel, nickel, lead, and zinc. Surface water quality criteria are determined according to the hardness of the receiving watercourse. These criteria are used to make judgments about surface water quality and are the basis for groundwater criteria used to assess the quality of groundwater that recurs as surface water. Finally, they are the key element in calculating environmental discharge objectives (EORs) used to assess the quality of wastewater discharges to the aquatic environment. For a discharge that occurs on an annual basis, the median hardness of the receiving water body is generally used to calculate water quality criteria for aquatic life.This third party metadata element was translated using an automated translation tool (Amazon Translate).