Drinking water advisories

A boil water advisory is issued when an accidental situation could affect water quality or, much more rarely, when bacteria are present in the water. 

Duration
Generally 48 to 72 hours, the time needed to conduct water analyses.  

Information
A notice is placed on your door: 

• At the beginning of the boil water advisory 
• At the end of the advisory. 

What to do

At home
Boil tap water at a rolling boil for at least 1 minute before consuming it, even if you have a home water treatment system.  

Use boiled or bottled water for : 

• Drinking or making beverages 
• Preparing baby formula and baby food 
• Washing and preparing raw foods 
• Preparing foods that do not require prolonged cooking (discard any food prepared with tap water on the day of the advisory) 
• Making ice cubes (discard those made on the day of the advisory) 
• Brushing your teeth and rinsing your mouth 
• Giving water to pets 

You can use tap water without boiling it first for : 

• Cooking food in boiling water 
• Running the dishwasher with hot water and the drying cycle 
• Washing clothes 
• Taking a shower or bath (avoid swallowing water and wash young children with a washcloth) 

Schools, Businesses, Shops, and Institutions 

• Turn off all water fountains. 
• Post a notice near all faucets. 

What to Do Once the Advisory is Lifted  

If the water is discolored, let the cold water run until it becomes clear. You can then use the water as usual. 

A do not consume water advisory is issued when tap water may be contaminated by a chemical product hazardous to health. This is very rare. 

Duration
Until the situation is resolved.  

Information 
A notice is placed on your door: 

• At the beginning of the do not consume water advisory 
• At the end of the advisory 

What to do

At home
Do not drink tap water, even if boiled, and even if you have a home water treatment system. 

Use bottled water or water from another safe source for : 

• Drinking or making beverages 
• Preparing baby formula and baby food 
• Washing and preparing foods (discard any food prepared with tap water on the day of the advisory) 
• Making ice cubes (discard those made on the day of the advisory) 
• Brushing your teeth and rinsing your mouth 
• Giving water to pets 

You can use tap water for : 

• Washing your hands (dry them well) 
• Washing dishes (dry them well) 
• Running the dishwasher with hot water and the drying cycle 
• Washing clothes 
• Taking a shower or bath (avoid swallowing water and wash young children with a washcloth; turn on the bathroom fan) 

Schools, Businesses, Shops, and Institutions

• Turn off all water fountains. 
• Post a do not consume notice near all faucets. 
• Shut off water play areas and indoor decorative fountains. 

What to do once  the advisory is lifted

If the water is discolored, let the cold water run until it becomes clear. You can then use the water as usual. 

A water interruption notice is issued when work on the water network in your area may require shutting off the water supply. 

Duration
Depends on the work being carried out.  

Information
A notice indicating the start and end times is placed on your door.  

What to do before
Store water according to your needs. 

What to do once the advisory is lifted

• If the water is discolored or smells of chlorine, let it run until it becomes clear and odor-free. 
• If your wastewater goes to a septic tank rather than the municipal sewer, try to let the water flow outside. 
• If a faucet with an aerator has reduced flow, unscrew and rinse it.  

You can then use the water as usual.

Each year, the City of Laval performs flushing operations on its water supply system with the objective of eliminating deposits that accumulate over time, such as calcium, iron particles and rust.

These operation also serve to:

• Maintain the proper flow of drinking water in the water mains.
• Ensure the proper function and durability of the water supply system, specifically the street valves and fire hydrants.
• Reduce cases of coloured water reported by residents.

Monday to Friday between 7 a.m. and 4 p.m. and between 8 p.m. and 1 a.m., from April to June and from September to November.

Why these schedules?

The work operations are performed outside of high water consumption periods to limit inconveniences (lower water pressure, murky or yellowish water colour).

Coloured water: The water can sometimes become yellowish, brownish or reddish due to small iron deposits on the pipes. This discoloration is temporary. If this occurs, let the cold water run for a few minutes until it becomes colourless. Be sure to remain nearby during this time.

Coloured water could stain fabrics and dishes. Residents are advised to wait until the water runs clear before washing clothes or dishes.

Drop in water pressure: A slight drop in pressure may occur temporarily.

Yes, water can be used and consumed as long as it is clear. However, fabrics and dishes should be washed outside of flushing operations.

Information signage will be installed at strategic locations in the concerned areas.