Sewage is backing up in my basement. What do I do?
Stop using water in the house first. Every toilet flush, tap and washing machine cycle adds to what is coming up.
Sewage is Category 3 water, sometimes called black water. It carries bacteria, viruses and parasites, and porous materials it touches generally cannot be cleaned and saved.
1. Stop running water
Toilets, sinks, showers, the dishwasher and the washing machine all discharge into the same line that is already backing up. Stop using them until the cause is known.
2. Stay out of it
Do not walk through it, and keep children and pets away. Sewage carries pathogens, and walking through it and then through the house spreads contamination into carpet and flooring elsewhere.
If water is near outlets or the electrical panel, treat it as an electrical hazard as well and have the power cut. Toronto Hydro: 416-542-8000.
3. Call 311 and report it
A blocked or surcharged municipal sewer main is a common cause. The City will send a crew to check the line under your street.
It also creates an official record of the date and the event, which matters both for your insurance claim and for any claim against the City.
4. Photograph everything
Before anything is moved or cleaned. Sewer backup is usually covered by a separate endorsement rather than the base policy, and claims on it are examined closely. Photographs of the water level, the affected rooms and the contents are what settle them.
5. Call a restoration contractor, not a cleaning company
Category 3 water requires containment, negative air pressure, HEPA filtration, removal and disposal of affected porous materials to regulation, and antimicrobial treatment of what remains.
Carpet, underlay, drywall and insulation that sewage has touched are not salvageable. Cleaning them and leaving them in place is how the smell comes back three weeks later.
6. Then stop it happening again
A backwater valve closes when the municipal sewer surcharges. The City of Toronto subsidises installation under its Basement Flooding Protection Subsidy Program, up to $6,650 per property for eligible work.
If your basement has backed up once, the same storm next year will do the same thing unless something changes.
Common questions
Why is sewage coming up through my floor drain?
Usually because the municipal sewer has surcharged in heavy rain and your floor drain is the lowest relief point, or because your own lateral is blocked by roots or a collapse.
Is sewer backup covered by insurance?
Only with the sewer backup endorsement, which is not included in a standard Ontario policy by default. Check your declaration page.
Can I clean up sewage myself?
It is not advisable. Category 3 water requires containment, protective equipment, HEPA filtration and disposal to regulation, and porous materials it touched have to be removed rather than cleaned.
How do I get rid of the sewage smell?
By removing the contaminated material. Once the source is gone, the surfaces are cleaned and treated and the area dried, the odour goes. Masking it without removing the source does not hold.
How long does sewer backup cleanup take?
Removal and cleaning is typically one to three days, followed by three to five days of drying. Rebuilding what was removed comes after that.