The mission entrusted to the Public Hygiene Department consists in providing the community it serves with drinking water of excellent quality and to store it in sufficient quantities to deal with emergency situations. It is also responsible for safely and efficiently treating and disposing of wastewater from Rosemère and Lorraine.

At your service

In addition to its director, the department has a secretary and eleven graduate water and wastewater plant operators.

Infrastructures and equipment

The department has two buildings: the water treatment plant and the wastewater treatment plant with seventeen pumping stations.

Drinking water

Serving a population of 32,000 (Rosemère, Lorraine and Bois-des-Filion), the plant produces an average of 650 litres/person/day. The goal is to apply the drinking water excellence program, which requires water of superior quality 100% of the time. To this end, it has a number of processing units such as 1 screen rake, 2 mechanical agitators, 2 dynamic settling tanks, 6 bilayer gravity filters (sand and granular activated carbon), 2 drinking water storage tanks, 2 electric generating sets, 1 process computer, 2 compressors and boosters and 1 telemetry system.


Serving a population of 27,000 (Rosemère and Lorraine), the plant has a maximum wastewater treatment capacity of 80,000 m3 a day. Complying with objectives set by the Department of Municipal Affairs and Regions with regards to the quality of waste calls for monitoring the bacteriological quality of water from the Mille Îles River. Process equipment for this task consists of 2 mechanical screen rakes, 2 grit chambers, 2 settling tanks, 1 UV disinfecting system, 2 digestors, 2 centrifuges and 1 process computer.

Fields of intervention

Operating 24 hours a day, the Public Hygiene Department ensures the production and distribution of drinking water as well as the collection, pumping and treatment of wastewater.

Its role includes:

  • tracking the quality of water throughout the entire water system
  • making the public aware of the importance of rationing the use of drinking water
  • contributing to application of watering regulations in the territory covered.