Short answer
A backwater valve is a one-way valve on your home's main sewer line. It lets wastewater leave the house and closes if sewage tries to flow back in from the city main. Installing one means cutting into the basement floor, and Utilities Kingston's Preventative Plumbing Program requires a licensed plumber to do it. The program may cover part of the cost.
How a backwater valve works
Normally, wastewater flows out of your house through the valve's open flap. When the city sewer backs up, the flow reverses and the flap closes, so the backup can't reach your floor drain, toilet or shower. While it's closed, water you use in the house has nowhere to go, so go easy on water during a heavy storm.
Do you need one?
- Your basement has a floor drain, toilet or shower below street level
- Sewage has backed up into your basement before
- You have a finished basement you can't afford to lose
- Neighbours on your street have had backups
Utilities Kingston's Preventative Plumbing Program
Utilities Kingston runs a Preventative Plumbing Program to help homeowners pay for flood protection such as backwater valves. Read about how backflow happens on their backflow page. We install backwater valves and can help you with the application.
Looking after it
Open the access cover once or twice a year and make sure the flap moves freely and nothing is caught in it. We'll show you how when we install it.
