Identify the key environmental issues related to the targeted areas of contaminated sediments

Context and project description

The first approach consists of identifying the areas of the St. Lawrence where the contamination of sediments may be concerning. This is done using criteria for assessing the quality of sediments in Quebec. Once these sectors are identified, we must evaluate and document, for each sector, the risk that contaminated sediments may present to the environment and to people. In other words, it means evaluating whether the contamination of the sediment in one site or another is sufficiently high to be potentially toxic to users: fish who feed or reproduce in it; humans who swim or fish in it or consume mollusks from it; cities that get their drinking water from it, etc.

The project will be done in several steps: identifying the areas of concern, defining and evaluating the general issues for each of these areas, developing technical sheets for the areas of concern.


This project involved identifying areas of concern in terms of sediment contamination, including certain sectors of the Quebec City and Montreal harbours, a channel in the Contrecoeur archipelago, and the Beauharnois sector of Lake Saint-Louis. Documents describing the issues specific to those areas are being drafted and research is continuing in other sections of the St. Lawrence River. The documents produced in this project will make it possible to assess the environmental and human health risks associated with the contaminated sediments at certain sites.

Participating departments

Government of Canada

  • Environment and Climate Change Canada
  • Public Works and Government Services Canada
  • Health Canada
  • Fisheries and Oceans Canada

Government of Quebec

  • Ministère du Développement durable, de l’Environnement et de la Lutte contre les changements climatiques