Service de l’environnement

DirectorRoger Lachance

The Service de l’environnement manages the quality of the air, water, soil and food in Montréal as well as waste materials (garbage, recycling, etc.). It also develops policies and action plans to advance sustainable development in Montréal.


The mission of the Service de l’environnement (SENV) is to improve the population’s quality of life and living environment across the Montréal agglomeration. It fulfills its mission by raising public awareness on environmental issues, promoting and monitoring the quality of the physical environment, acting to ensure responsible management of waste materials and resources across the region, and monitoring the quality and safety of food in food-related establishments.

SENV also acts as an environmental protection expert on behalf of Montréal and borough departments, related cities and other agencies and, in this role, develops policies, programs and action plans, all consistent with the green transition. To ensure compliance with regulatory requirements, it issues environmental permits and monitors industrial emissions through air and water sampling.

Air Quality

Montréal was the first Canadian city to concern itself with air quality in Canada. Through its air quality surveillance network, it has contributed actively to Environment and Climate Change Canada’s National Atmospheric Pollution Surveillance Program since 1969.

Atmospheric pollutants are measured using cutting-edge technology in order to publish the air quality index (in French) in real time.

Aquatic Quality

The Réseau de suivi du milieu aquatique (RSMA) analyzes and documents the quality of Montréal’s surrounding waterways. The RSMA conducts sampling on these tests and interprets up to 20,000 chemical, physical and bacteriological tests per year.

The network began its activities in the 1970s, at a time when the waters surrounding the island of Montréal were of poor quality. Its objective was to gain an overview of water quality before and after the installation of a wastewater interception and treatment system. The RSMA went on to develop various water sampling programs, including  COURDO, QUALO, RUISSO, and PLUVIO. All were geared to enhancing waterways and prioritizing actions aimed at protecting them.

Please view the map (in French) of water quality, measured under RSMA sampling programs.