Rosemont reservoir : last phase of construction work

Last updated August 4, 2021
Reading time: 2 min

Did you know that the water distributed to your tap is first channeled through a reservoir? The reinstatement of Montréal’s largest reservoir, the Rosemont reservoir, is therefore very important. The last phase of the work will begin at the end of the summer.

Find out everything about this worksite

Tests will be carried out on the conduits it is connected to. The reservoir was shut down in the 1980’s and will resume its operations by the end of fall, 2021.


From the end of August, until November 2021

Last phase of the work

Starting in August, the city will undertake the last phase of the major reconstruction of the Rosemont reservoir. A series of tests will check every system associated with the commissioning of the new pumping station and reservoir.  

All necessary precautions will be taken to avoid hindering water distribution. However, these operations may cause some noticeable inconveniences. You may, for instance, see a drop in water pressure, or color changes in your tap water (a slight yellow, red, brown or grey colouring). These episodes will generally last a very short period of time.

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Following the testing phase, the reconstruction work carried out on the reservoir and on the pumping station will namely enable the city to: 

  • enhance the safety of drinking water supply for Montréal’s north and east sectors;
  • service a new zone for the boroughs of Saint-Léonard, Anjou and Mercier–Hochelaga-Maisonneuve;
  • provide a more flexible water distribution for the water system;
  • stabilize water pressure during high demand periods, in summer. 

A new sealing and drainage system, including a leak detection system, has also been installed above the reservoir slab.

Developing to serve Montrealers

One of the benefits of this commissioning is the redevelopment of Parc Étienne-Desmarteau, where the reservoir and pumping station are located. In order to provide a nice environment for Montrealers to enjoy recreation, sports and nature, work was also carried out to configure: 

  • public squares
  • a lookout
  • a multi-function sports field
  • a skatepark

What’s more, the public running track was upgraded to Olympic standards, so as to provide optimal training conditions.

Did you know?

The Rosemont reservoir is Montréal’s largest reservoir. It can contain 227,000 m3 of water, the equivalent of 61 Olympic pools. Its surface area of 35,642 m2, is equivalent to 5 soccer fields. Its commissioning will increase the city’s drinking water supply by 40 %.

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