What is Backflow?
Backflow is the undesired reversal of water flow within a plumbing system. This can occur two ways:
- Backpressure: The pressure within a building is greater than the drinking water system pressure. This results in the water within that building being forced backward and into the drinking water system.
- Back Siphonage: The pressure in the drinking water system is decreased to a negative pressure resulting in the water within the building being siphoned into the drinking water system.
In these instances, the unprotected cross connections to the drinking water system can contain contaminants which can be drawn or forced back into the drinking water piping and distributed throughout the City water system. This can result in unsafe drinking water on the property and in the entire drinking water system, putting the citizens of the community at risk.
What is a Cross-Connection?
A cross-connection is any connection between drinking water and any source of pollution or contamination. Cross connections pose a hazard to the drinking water system if backflow were to occur, causing contaminated water to enter the drinking water system.
What is a Backflow Prevention device?
A Backflow prevention device is a mechanical device installed on a water service downstream of the water meter to prevent backflow.
What steps is the City of Owen Sound taking?
The City of Owen Sound has already conducted a cross connection survey of the plumbing in properties that will require a backflow preventor. In this survey the risk of contamination was assessed for cross connections at these buildings. Buildings will require a level of backflow protection appropriate to the level of risk.
The next step will be for the City to contact the property owners/managers and plan to have their backflow preventer installed.
Going forward after the installation of the backflow preventors, it will be the property owner’s responsibility to:
- Ensure their backflow prevention devices are tested and maintained every year by a certified backflow preventer tester.
- Have the tester submit the testing reports to the City (or their representative)
To comply with the City’s by-law, testable backflow preventers shall be field tested at the following times:
- Upon installation
- When cleaned, repaired, or overhauled
- When relocated
- When property ownership changes
- Annually