The Cross Connection Control Program is in place to ensure the safety of our water supply through backflow prevention.

The City of Cambridge Water Use By-law #146-03 requires that all buildings (except some residential properties) be equipped with backflow prevention devices. These devices need to be maintained and tested regularly by a certified backflow prevention device tester licensed by the City of Cambridge. 

Please follow the Instructions for Compliance to the Cross Connection Control/Backflow Prevention Program

* NEWThe Cross Connection Control Program at the City of Cambridge is going paperless!

Cross Connection Online Submissions

Read more about Lead Free Backflow Prevention Devices

What is backflow and how would this occur?

Backflow means a flowing back or reversal of the normal direction of water flow.

The water supply system is normally pressurized to make sure water flows into your building or plumbing system, but there are times that pressure may be reduced.

If the pressure drops enough that the flow of water reverses, unwanted substances could flow backwards and contaminate the public water supply. 

What is a Cross Connection?

A cross-connection is any connection, whether permanent or not, between the public potable water system and a possible source of contamination.

Some examples of cross-connections are fire sprinkler and irrigation systems, or plumbing connections to equipment that uses water, such as beverage machines, dental chairs and dialysis equipment.

What is a backflow prevention device?
Backflow preventers are mechanical devices that prevent water from flowing backwards into a water supply.There are degrees of protection ranging from a vacuum breaker on a garden hose line to reduced pressure zone backflow preventers commonly used in an industrial setting where chemicals are connected to water lines. The type of device required and location it is installed depends on the application and the threat level.
A building permit is required for a new backflow preventer or new plumbing system. Visit the building permit page or contact for more information. 
What if I choose to not install a backflow device?

The by-law mandates that every building, except for some residential buildings must be equipped with backflow prevention devices. Failure to install and maintain these devices could result in having your water shut off, and/or a fine.