Homeowner guideEmergency guide
What to Do When Sewage Backs Up
Sewage in your basement is unpleasant and unsafe. Here is what to do right away and how to prevent it from happening again.
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- Short steps a homeowner can follow safely
- What to check before you pick up the phone
- Clear signs it is time to call a plumber
- Markham and York Region notes where they matter
- Licensing details confirmed when you call
- Residential
- Commercial
- Markham & York Region
The short version
- Keep children and pets away.
- Do not touch sewage without gloves and boots.
- Keep clear of pooled water anywhere near plugs or appliances.
- Ventilate the area if you can.
Immediate steps
- Stop using water in the house: no flushing, laundry or showers.
- Call a plumber to clear the blockage.
- Call your insurance company.
- Take photos and videos of the damage.
- If the backup is from the city sewer, contact the City of Markham.
Cleanup
Sewage contains bacteria and other contaminants. For more than a small spill, a professional cleaning company is recommended. Porous items like carpet, drywall and insulation that have been soaked usually need to be removed.
From the van: Do not use the basement floor drain to empty mop buckets until the line is cleared and checked.
Prevention
- Install a backwater valve.
- Do not flush wipes or pour grease down drains.
- Have the sewer line inspected if you have had backups before.
- Cut any downspout that still feeds the sewer and let it spill onto grass.
City programs
The City of Markham has offered subsidies for backwater valves and other flood protection. Check the current terms and requirements.
Talking to your insurer
Sewer backup coverage is usually an add-on rather than part of a basic home policy. Ask your broker whether you have it, what the limit is, and whether a backwater valve or other protection lowers your premium or deductible. Keep receipts for any cleanup and repair work.