Surface water quality encompasses a wide range of conditions that are part of the aquatic environment in a waterbody. In turn, the aquatic environment provides diverse habitat and a clean water supply for aquatic life, wildlife and humans. In Alberta, there is a wide variety of aquatic ecosystems across the mountain, boreal and prairie-parkland regions.

There is no single or simple measure of water quality. Water may be tested for a few characteristics or numerous natural substances and contaminants, depending on the need. This can be done using traditional methods, such as collecting a representative water sample from a waterbody and sending it to a laboratory for analysis. Surface waters may also be analysed more immediately using basic, hand-held electronic meters. More sophisticated electronic meters can also be installed that can store and transmit data via satellite technology.

Water quality measurements fall into three broad categories:

  1. Physical characteristics such as temperature, colour, suspended solids and turbidity;
  2. Chemical characteristics such as nutrients, minerals, metals, oxygen, organic compounds and a wide range of pollutants (e.g., pesticides, hydrocarbons, pharmaceuticals, PCBs); and
  3. Biological characteristics such as the types and quantities of bacteria, protozoan parasites, algae, invertebrates, plants and other animals. 

Physical, chemical and biological measurements can be used together to describe the overall quality or health of aquatic ecosystems.