Sewer Backups and Basement Flooding

Halton Region provides an emergency service, 24 hours a day, seven days a week, to deal with blockages in the wastewater sewer system. Blockages can occur in the sewer pipe that connects the drain in your home or building to the Regional sanitary sewer system.

If the blockage in the wastewater sewer lateral (or pipe) that occurs on the municipal side of the wastewater sewer system, unless the blockage is caused by objects or materials of any kind originating from the private building drain or sewer. A fee will be charged (as per Halton’s Council-approved User Fee Schedule) for clearing a blockage in a wastewater pipe that occurs on or originates from the private side of the wastewater sewer system.

Diagram of house that shows homeowner responsibility, property line, storm lateral, wasterwater lateral, storm sewer main and wastewater sewer main

What to do when after experiencing a backup:

  1. If you experience basement flooding, contact Halton Region by dialling 311 (24 hours a day, seven days a week). 311 Halton staff will attempt to determine the source of flooding and if necessary request Halton Public Works staff make a site visit to inspect the problem. Halton Public Works staff will assess the flooding, attempt to determine the flood source and clear any identified blockages in the wastewater sewer system.
    • Don't use toilets or sinks unless it is absolutely necessary until the issue has been resolved. (Any water sent down the drain may end up in your basement.)
    • If water has risen above electrical outlets or water is near electrical panels, you should consider shutting of your hydro. Contact your local hydro company if necessary.
  2. Call your insurance company as soon as possible and report property damage caused by the flooding:
    • Take photos of damage caused by flooding for your insurance claim.
    • Keep receipts from emergency repair work or clean-ups done to prevent or reduce further damage.
    • Contact your insurance company to discuss coverage.
  3. Carefully clean the affected area and consider hiring a professional cleaning company familiar with cleaning sewage backups.

    Be mindful of health and safety when cleaning up your flooded basement. Exposure to contaminants carried by flood water or sewer backups into basements can be dangerous. Homeowners may be exposed to waterborne diseases, corrosive cleaning agents and irritants.

    • Keep children and pets out of the affected area until cleanup has been completed.
    • Dress appropriately – wear overalls, gloves, protective eyeglasses, rubber boots and a mask.
    • Sanitize walls and floors using a solution of household bleach (mix 1 cup bleach with 5 gallons of water) or hot water and liquid detergent.
    • Rinse and thoroughly dry and ventilate the area. Use a de-humidifier, fan or open windows to let fresh air in.
    • If you can, shut off the electrical power. (Note: would affect the operation of a sump pump or sewage ejector).
    • Stay away from electrical equipment. Electrical accidents may occur because of contact with water and electricity. Have a licensed electrical contractor assess the situation to determine if there are potential electrical hazards.
    • Water could extinguish a pilot light on a gas appliance. If you detect gas, leave the house immediately and contact the gas company.
    • Minor debris can be put out for regular garbage pick-up. Discard all contaminated items that cannot be washed and disinfected, (such as, mattresses, carpeting, carpet padding, rugs, upholstered furniture, cosmetics, plush toys, baby toys, pillows, foam-rubber items, books, wall coverings, and most paper products).
    • Remove and discard drywall and insulation that has been contaminated with sewage or flood waters.
    • Visit to learn how to properly dispose of waste or household hazardous materials.
    • Wash all clothes worn during the cleanup in hot water and detergent. These clothes should be washed separately from uncontaminated clothes and linens.
    • Throw out canned foods, home-prepared food in jars, meats and dairy products and any packaged foods that may have been affected by the flood waters – check for damaged packaging, leaks, and corrosion at seams and joints of cans.
    • If your freezer's power is off, move the frozen food to another freezer or throw it out if you can't keep it frozen.
    • If in doubt, throw it out. Do not consume potentially contaminated food. For more information on food safety dial 311 to be connected to Halton Region Health Department.
  4. Apply for the Sewer Backup Flooding grant. If your basement has flooded due to a wastewater sewer backup, you may quality for financial assistance in the amount of $1,000 from Halton Region. This grant can help residents to either offset the cost of a deductible under their personal home insurance policy or help with flood related cleanup costs.

    The grant may be available if a blockage occurred on the municipal side of the wastewater sewer system or if the wastewater sewer backup was the result of a storm surge.

    Blockages on the private side of the wastewater sewer system and blockages that are the result of objects in the drain that originate from the building or private side of the wastewater sewer system will not qualify or the grant.

Download the grant application form. To apply for the sewer back up grant residents must first report the sewage backup to Halton Region.

For more information please contact Halton Region by dialing 311.