Backflow Prevention

On June 1, 2026, the Town of Hanover passed a Backflow Prevention Bylaw. The bylaw’s purpose is to ensure that the town continues to provide safe, high-quality drinking water to our community by decreasing the chance of backflow into our municipal drinking water system.

The Town is legally responsible under the Safe Drinking Water Act, Section 19, Standard of Care to exercise due diligence in the operation of its water system. The installation of backflow preventers is a requirement for specific types of buildings under Section 7 of the Ontario Building Code. Specifically, this bylaw applies to Industrial, Commercial and Institutional properties in the Town.

This bylaw won’t impact residential property owners. In residential buildings, there are limited cross connections and lower risks.

The Town of Hanover is using BSI to track premise backflow test results. The tester will be required to log the results at BSI Online.

Go to bsionline.ca/ and click the New to BSI link
Create username, password and company profile
Login to add testers and test kits under the "manage" tab
Upload or send copies of all applicable licenses and test gauge calibrations for all testers to BSI
If you require a qualified backflow tester, please see list at: owwa.ca/tester-list/.

Backflow Prevention FAQs

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 Town 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.