From May 2 to July 31, between 10 p.m. and 6 a.m.

Starting May 2, operations will begin at night with the flushing of the main lines. This preparatory work, which will take about a week, will ensure the success of the complete one-way flushing of the territory.
Despite all the precautions taken by the City, this operation can cause a slight drop in pressure accompanied by rust-coloured water. If this should occur, we recommend that you let the water run until it is clear.
Carried out by Aqua Data, these operations take place between Sunday evening and Friday morning, from 10 p.m. until 6 a.m. The quality of drinking water will not be affected. 
This one-way rinsing operation removes deposits in the pipes and ensures the continued supply of good quality drinking water.