Rivers and lakes

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Rivers and lakes

Over the years, the Ministère has set up various water quality surveillance networks to acquire data and knowledge on the state of its lakes and rivers. These networks are specifically designed to monitor the different aquatic environments (St. Lawrence, other rivers, lakes), a wide range of ecosystem components (water, sediments, algae, cyanobacteria, benthos, fish) and the many different substances of concern (pesticides, toxic compounds, metals, etc.). The 2020 Report on the State of Québec’s Water Resources and Aquatic Ecosystems (French,

PDF, 100 MB) provides the status and trends observed in the water quality of rivers and lakes of southern Quebec and the St. Lawrence River.

Topics

Monitoring aquatic environments (French)
Réseau de surveillance volontaire des lacs (RSVL)
Blue-green algae
Guide to eating Québec freshwater sport fish (French)
Rivers and watersheds (French)
Lakes (French)
Lac-Mégantic rail disaster (French)
Physicochemistry and bacteriology (French)
Dissolved salts – chlorides and sodium
Pesticides
Toxic substances
Fish
Benthos (French)
Riparian zone
Guides and protocols
Quality criteria:
- Surface water in Québec (French)
- Sediments in Québec (French)

Recent publications

Loadings of six physical chemical and bacteriological parameters at the mouths of the main tributaries of the St. Lawrence River – 2013–2017 (French, PDF, 3 MB)
Guide to monitoring benthic macroinvertebrates in Québec freshwater (coarse substrate) - Update (French)
Guide to eating Québec freshwater sport fish - Update (French)
Preliminary opinions and findings on chlorides in surface waters and their potential effects on aquatic life, Grenier et al, 2024 (PDF, 1.8 MB)
Sampling protocol for toxic substances in freshwater sport fish - Update (French)
Guide to river water quality trend analysis using the Exploration and Graphics for RivEr Trends (EGRET) software package (French, PDF, 2.4 MB)

If you would like to receive the latest list of publications on aquatic environments that are available from the Direction principale de la qualité des milieux aquatiques, please subscribe by email to dgsee@environnement.gouv.qc.ca.