Backwater valve explained

A backwater valve is a backflow prevention device used to prevent outbound water through a dwelling's drain pipes from re-entering -- "back flowing"—into a home. The valve contains a flap that allows water to exit the home, but closes to prevent the back flow into the home.[1]

Backwater valves commonly activate when a city's sewer lines are unable to handle a large amount of falling precipitation; this puts homes that are tied into the storm lines at risk of having water back flow into them.

There is a big difference between backwater valves and backflow preventers:

See also

Notes and References

  1. Web site: Backwater Valve. www.london.ca. 2021-11-23. 2019-12-11. https://web.archive.org/web/20191211214232/https://london.ca/residents/Sewers-Flooding/Basement-Flooding-Causes/Pages/Backwater-Valve.aspx. dead.