What to do after a flood

Last updated February 18, 2024
Reading time: 4 min

There was a flood, and you were evacuated. Now what? To return home safely, follow these steps – and find out how to identify potential hazards and clean your house.

When to go home

Before going home after a flood, you need authorization from the Service de sécurité incendie de Montréal. And when you do go back, you need to make sure your home is safe.

Are you in doubt about the state of your house? Call 311 to schedule an inspection.

Is there imminent danger? Call 911 and ask responders to come quickly.

Going home

It’s better to go home in the daytime so that you can see what’s been damaged. As soon as you get home, look carefully at the inside and outside of the house to identify damage and potential hazards.

Is major work required before you can move back in? Take steps to secure your home against looters.

Damage and claims

  • Make a list of all damage, both inside and outside your house.
  • Take photographs or make a video showing the damage.
  • Send the documents to your insurance company so that it can see the damage.
  • Keep receipts for all purchases.
  • Find out about thegeneral indemnity and financial assistance program provided by the Ministère de la Santé publique.
  • If your house was flooded because of a sewer backup caused by spring flooding, and you suspect any kind of non-compliance or breach in the city’s water and sewer system, you can ask for system verification. Call 311 to find out what to do.

On the outside

  • Inspect the building structure to detect any sign of weakness such as cracks, bulges, or crumbling mortar joints. If you see any of these, call 311 to schedule an inspection. You will be able to move back in when the building is safe.
  • Make sure foundations have not been damaged and structural elements have not been carried away by flooding. If you see any evidence of this, leave immediately and call 911: your safety may be threatened.
  • Remove sandbags or anything else from doors and windows.
  • Put broken branches, sandbags and other debris in a single pile on your property, near the street. You may be given special instructions regarding disposal (special collections or drop-off locations).
  • Call 311 to report any dangerous item on the street or sidewalk near your home such as uprooted trees, broken branches on a vehicle or that appear to be in danger of falling, major debris obstructing the road, displaced sewer covers or displaced traffic signage.
  • Contact Hydro-Québec to report damaged electrical wires. If telecommunications wires are severed, contact your telecom provider.
  • If an outdoor propane or oil tank seems to have a faulty connection, hire a member of the Corporation des maîtres mécaniciens en tuyauterie du Québec to inspect and restart the device.
  • When a vehicle (car, motorcycle, motor home or trailer) has been flooded, it is no longer safe. See theflood-damaged road vehicles page on the Société de l’assurance automobile du Québec website.

Inside the house

Walls, floors and ceilings

  • Gradually remove water by pumping it out of the basement. Be careful: If water is pumped out too quickly, foundation walls may be damaged and could even collapse.
  • Inspect walls and floors and note any signs of sagging or weakening, such as bulges, warping or buckling. If you see any of these, leave the house immediately and have it inspected by a professional such as a building inspector.
  • Remove any interior finish items that are waterlogged and might fall or come off.
  • Make sure your smoke and carbon monoxide detectors are working.


  • Never go into a flooded room that contains cables or electrical appliances that are turned on. 
  • Never touch an electrical panel that has been in the water. Contact Hydro-Québec and go to this page for more information:Safety and electricity – what to do in case of a flood.
  • Hire an electrical contractor who is a member of theCorporation des maîtres électriciens du Québec to inspect and repair or replace your electrical equipment. 
  • Do not plug in any electrical appliance if there is water on the ground or if your hands or feet are wet.
  • Have a repair expert or a master electrician check household appliances and light fixtures that have been affected by flooding. You will need to replace the filters and insulation of water heaters, refrigerators and freezers.
  • If you have to use candles or oil lamps until repair work is done, followsafety instructions
  • If your house is equipped with a fire alarm, make sure it is working. If it is not, contact the alarm company before moving back into your home.

Combustion devices using natural gas, propane or oil

  • If a device such as a generator or pump is intended to be used outside, do not use it inside the house. These appliances can produce fatal amounts of carbon monoxide.
  • If you are using a combustion device that is intended for indoor use, such as a propane heater or space heater, make sure you have a carbon monoxide detector.
  • Ask a member of the Corporation des maîtres mécaniciens en tuyauterie du Québec to inspect appliances fuelled by natural gas, propane or oil, and to do whatever repair work is needed. The Régie du bâtiment du Québec provides alist of devices to be checked after a flood, organized by type of appliance.
  • Contact Énergir if the natural gas supply was shut off. Follow the security procedure on the Énergir website. 
  • Keep the natural gas valve closed. If it is open and any appliance has been immersed in water, shut the valve and contact Énergir.
  • Follow safe practices if you use or store hazardous materials (such as combustible or flammable materials).

Heating systems

  • Have a qualified person check your central heating system before you turn it back on.
  • Carefully clean, or replace, all supply and return air ducts that have gotten wet.
  • Replace furnace filters and insulation.

Drinking water

Unless otherwise specified, water from the water supply system is drinkable. If you have any questions, call 311.

Check to see if your sprinkler system is working. If it is not, contact your supplier to restart it before you move back in.

Waste water

If waste water from your home is evacuated through the city sewage system, the system will be working as usual.

  • If your septic tank system is not working properly, call on a qualified person to fix it.
  • If you empty the tank, make sure you leave enough liquid in it. Otherwise, if the ground is saturated with water, the tank may end up floating.

Cleaning and preventing mould

The most vulnerable people (old people, young children, pregnant women, people with respiratory problems or compromised immune systems) should leave the house until the cleaning is done.

Mould may take different forms in your house. This is what you should watch for: 

  • greenish or black spots
  • stains, bulges, or other signs of water infiltration
  • an unpleasant mouldy or earthy smell

Cleaning instructions

  • Use appropriate products to disinfect surfaces that may have been in confact with dirty water. Wear rubber boots, protective goggles and an antidust mask.
  • Ventilate and dehumidify your home until all surfaces are completely dry.
  • Remove the wet part of the drywall and other elements of your walls (such as insulation) up to at least 50 cm (20 inches) above the level reached by the water. Leave the walls open until wood and other materials are completely dry. This may take several weeks.
  • Get rid of all absorbent items that were in contact with the water, including rugs, mattresses, and upholstered furniture.
  • All food, medications, toiletries and beauty products that were in contact with the water should also be thrown away.
  • Get rid of hazardous household waste (such as paint, used oil and solvents) by taking it to anecocentre.
  • To avoid increased risk of fire, do not pile up demolition debris either inside or outside your house.