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Nearly every year, various regions of Québec grapple with flood risks. Although flood waters generally rise in the spring, when the snow melts, and in summer downpours, in the last few years we have witnessed flooding in other seasons and even in winter. When water levels are rising, you can limit damage and inconvenience by taking the following steps.

Châteauguay Info-River

To learn more about the rivière Châteauguay and to follow the evolution of its water level, you can consult the Châteauguay Info-River page.

  • First, inspect your home to ensure everything is in place for maximum safety.

    Cracks in the foundation or concrete slab in the basement are passageways for water. Have them sealed immediately. If the damage is significant, they will have to be repaired from the outside.

    Basement windows and openings:
    Water that accumulates around the building often infiltrates through the basement windows. A height of at least 20 cm (8 in.) between the ground level and the base of the window is recommended. If this clearance is not possible, you must install window wells, which will protect the opening in the foundation by channelling water toward the foundation drain.

    Roof drainage:
    For flat-roofed houses, water must be directed toward the storm sewer. For slope-roofed houses, eaves troughs are essential to quickly direct water away from the house. A horizontal section connected to the foot of the downspout or a storm diverter should be used to direct water as far away from the foundation as possible

    Floor drain:
    All basements need a floor drain to allow accumulated water to run out.  The drain should have a perforated screen rather than a cover. It should also be protected by a backwater valve to provide extra protection against sewer backups.

    Sump pit:
    Also called a sump tank, this is the hole in which a sump pump is installed. It holds excess water until it can be pumped outside. Sump pits can be installed in basements that do not have one by cutting a hole in the concrete slab. Pre-fabricated sump pits can easily be found on the market.

    Sump pump:
    A sump pump expels water that accumulates in the sump pit. It must be able to pump the water at least 3 m (10 ft.) away from the house. It should be carefully checked regularly. Test: float level, flap valve, electricity supply, support column and expulsion capacity.

    Backwater valve:
    This basically prevents water from backing up from the sewer. To avoid sewer backups, make sure there are backwater valves on the connections to the sinks, floor drains, toilets and showers in the basement. They should be easily accessible for maintenance (once or twice a year). Backwater valves cannot be installed on the main line.

    Land drainage:
    To drain water from your land, it should slope at least 1% away from the house. This will direct water toward the street, rather than the house.

    Basement garage:
    To avoid having water infiltrate a garage below street level, install a hump in the driveway, an outside drain connected to the storm drain and an inside drain connected to the domestic drain.

    • Put items stored in the basement or ground floor on high shelves or take them upstairs.
    • Put away chemical or toxic products such as insecticides and used oil which, when mixed with water, could be dangerous for the health and safety of residents, making sure they are out of the reach of children.
    • Block storm drains in the basement if they are not equipped with backwater valves.
    • Block the basement drain.
    • Reduce your use of water. As the drainage system is already working at capacity, try to avoid adding to the load: do not use the dishwasher or clothes washer, do not run water in the tub and sinks and do not flush the toilet. Turn off the water main if the situation gets worse.
    • Turn off the electricity. If the water starts to rise, make sure your feet are on a dry surface and use a wooden stick to turn off the electricity. If water starts to enter your home, do not touch anything and contact Hydro-Québec immediately to shut off the electricity.
    • Close the main gas line and shut the valves on propane tanks.
    • Turn off the valve for your heating oil tank.
    • Put away or attach anything movable on your property, to avoid having it swept away by the water.
    • If the municipality is distributing sandbags, lay them out to form a dike.
    • Plan a place to go for refuge if the situation requires it.
    • Take your insurance papers with you.
    • Monitor the development of the situation on the radio, TV or internet. Follow all safety instructions issued.
    • If you can smell gas or see that your natural gas equipment is damaged, contact the emergency service of your natural gas supplier.
    • If you use a generator, follow the installation and usage instructions.
    • Keep in contact with your family and friends with short telephone conversations, to avoid overloading the phone lines.
    • Use text messages, emails and social networks, if possible, but remember to conserve battery power on your mobile device.
    • Evacuate your home if the water level forces you out or if the authorities ask you to evacuate. Take with you essential items such as warm clothing, medication, toiletries, health insurance card, debit and credit cards and, if it is raining, raincoats.
    • Avoid walking or driving on flooded roads. Abandon your vehicle if the engine stalls.
    • Check the road conditions before heading out.
    • Inform the municipal authorities where they can contact you if you do not go to a municipal shelter.
    • In case of health problems caused by water infiltration, contact the Châteauguay CLSC Info-Santé line at 450-699-3333, 24 hours a day.
    • Contact your insurer as soon as possible. Keep invoices for accommodations, food, etc., for your insurance claims
    • If the authorities allow it and your safety will not be compromised, you can return home, preferably during the day, when it is easier to spot problems and danger. When you arrive, take photographs to document the damage to your home.
    • Consult with an electrician before turning on the electricity.
    • Consult with a specialist before turning on heating devices.
    • Assume water from a private well is not safe to drink, even if it seems clear and odourless. Until you are certain that the well water meets standards, boil it at full boil for one minute before drinking it or else use bottled water.
    • Assume water from the public waterworks system is safe to drink unless an advisory to the contrary is announced by the municipal authority in charge. If you have doubts about the colour, odour or taste of the water, contact the municipal authorities before consuming it.


    • Before starting the clean-up work on your home, it is very important to put on rubber gloves to avoid contact with the water and soiled materials, because the risk of infection is high. Always wash your hands well afterward as well. Even after the surfaces are dry, they may harbour bacteria and cause infection. Keep children out of the contaminated area.
    • As you gradually pump the water out of the basement, be extremely cautious to avoid asphyxiation, electrocution and setting fires.
    • Be especially careful using gas- or propane-fuelled pumps! They may be a source of carbon monoxide poisoning, which can cause symptoms ranging from headaches to coma and death.
    • Remember that these asphyxiating gases are odourless, colourless and painless. It is best to place these devices outdoors.
    • If you or anyone helping starts to feel bad, turn off the pump and call a doctor immediately.
    • Use soapy water to clean all surfaces, cavities and structures that got wet.
    • Once this is finished, disinfect the surfaces with a bleach solution (250 ml (1/2 cup) 5% concentrated bleach in 8 litres (2 gallons) of water), making sure you keep the area well ventilated.
    • Rinse and clean all floors. If there is a subfloor, make sure all the water has been removed. Wash the subfloor. Dry it out quickly and thoroughly and check for mould. Wait until everything is completely dry before closing cavities.
    • Check the walls up to 50 cm (20 in.) above the waterline and throw away all absorbent materials that could encourage the growth of mould, such as plasterboard, mineral wool, carpets, pressboard, mattresses, cloth toys and upholstered furniture that got wet.
    • Air out or dehumidify the house to bring the humidity level back to normal. In winter, it should be between 40% and 50% and it should never exceed 60%.
    • The yard will also need to be properly cleaned. Get rid of all garbage and detritus that could attract vermin and provide a breeding ground for flies.
    • Never touch electrical equipment and wires that are on the ground. Contact Hydro-Québec if you see electric wires on the ground.

    Precautions to take

    • Throw away all food that may have come into contact with the water, including bottles and jars. All undamaged tins must be washed and disinfected. For all other foods, ensure they are safe before you consume them.
    • Return to the pharmacy any medication that may have come into contact with the water, so the pharmacist can destroy it safely.
    • Sterilize contaminated kitchen items with boiling water.
    • Throw away all beauty products and other toiletries that may have come into contact with sewer water.
    • Change the insulation in your water heater, refrigerator or freezer if it got wet.
    • Look for signs of mould (odour of mildew, earth or alcohol, green or black spots on the floor or walls), as mould can cause health problems. If you develop health problems, see a doctor immediately.
    • Never drive a vehicle that has been flooded, including a motorcycle or recreational vehicle (trailer or camper van).


    • Before using your plumbing equipment, make sure that the municipal wastewater network or your septic tank is working.
    • Clean or replace aerators, shower heads and flexible tubing.
    • Check and clean, if necessary, the evacuation openings of sanitary appliances and make sure they are working properly (including the inside of the toilet tank and the overflow of sinks and bathtubs).
    • Clean sump pits and make sure sump pumps are working.
    • Locate, check and clean floor drains and backwater valves.
    • If necessary, have backwater valves checked by a certified inspector.
    • Empty, clean and replace water softening filters, if necessary.


    • Draw up a list of the damage caused by the water to your property and to all damaged objects, with descriptions, serial numbers, purchase dates and supporting photos or videos.
    • Keep the damaged objects if they present no danger.
    • Collect the receipts and proofs of purchase for items you bought during the disaster, as well as invoices for repairs or renovations. Keep any receipts for accommodations and meals during your evacuation.
    • Make sure you entrust your repair, restoration or renovation work to a licensed contractor. Before doing the repair work, contact the Division des inspections et des permis to make sure you have all the required permits.

This information is also available in a brochure produced by the city on floods and heavy rains . Paper copies are available in all municipal buildings.

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