Saint Lawrence River Basin Long-term Water Quality Monitoring Data

Long-term freshwater quality monitoring data for over 40 sites in the St. Lawrence River basin for the past 15 years or longer for nutrients, metals, major ions, and other physical-chemical variables are included in this dataset. Monitoring is conducted by Environment and Climate Change Canada (ECCC) as well as through the Canada-Quebec Water Quality Monitoring Agreement and the St. Lawrence Action Plan to assess water quality status and long-term trends, detect emerging issues, establish water quality guidelines and track the effectiveness of remedial measures and regulatory decisions. Data for sites operated by the province are available from Quebec's Sustainable Development, Environment and the Fight against Climate Change Ministry.

Supplemental Information http://www.ec.gc.ca/eaudouce-freshwater/default.asp?lan g=En&n=50947E1B-1

Data and Resources

Additional Info

Field	Value
Last Updated	April 17, 2026, 17:41 (UTC)
Created	April 17, 2026, 17:41 (UTC)
contact_person	{}
criticality_level	[]
data_dictionary	[]
geographic_scope	["2", "3"]
open_canada_collection	primary
open_canada_date_published	2016-05-02 00:00:00
open_canada_keywords	{"fr": ["Monitoring", "Surveillance", "L'état", "Les nutriments", "Les ions majeurs", "Transfrontalier", "Pesticides", "Organiques", "Plan d’action Saint-Laurent", "Saint-Laurent", "Yamaska", "Richelieu", "Saint-Maurice", "Saint-François", "Nicolet", "Chaudière", "Qualité de l'eau", "Eau de surface", "Tendances", "Fleuve / Rivière", "Lac", "Environnement", "Indicateur environnemental", "Métal", "Accord fédéral-provincial"], "en": ["Monitoring", "Surveillance", "Status", "Nutrients", "Major ions", "Transboundary", "Pesticides", "Organics", "St. Lawrence Action Plan", "St. Lawrence", "Yamaska", "Richelieu", "Saint-Maurice", "Saint-François", "Nicolet", "Chaudière", "Water quality", "Surface water", "Trends", "Rivers", "Lakes", "Environment", "Environmental indicators", "Metals", "Federal provincial agreements"]}
open_canada_subject	["nature_and_environment"]
sensitivity_level	unrestricted
title_fr	Données de monitoring de la qualité de l'eau à long terme du Bassin du fleuve Saint-Laurent
update_frequency	P3M