Cross Connection Control Program

Purpose of the Program

In order to ensure the delivery of safe, clean drinking water to the residents and businesses within the municipality, the City Of Peterborough has passed a by-law requiring all Industrial, Commercial, Institutional and some Multi-residential properties to comply with the CSA Standard for the installation and maintenance of backflow prevention devices.


  • "Backflow" is the undesired reversal of water flow against the normal direction;
  • "Backflow Prevention Device" is a mechanical device that prevents backflow and is sometimes called a backflow preventer;
  • "Cross connection" is a connection between the municipal water system and any source of contamination.

How Backflow Can Happen

  • Backflow can occur when the water pressure in the municipal delivery system drops, as in the case of a water main break or when the Fire Department is drawing water from a fire hydrant.
  • Backflow may also occur when pumps on a private plumbing system raise the water pressure within a building to a level higher than the water pressure in the municipal water main.
  • Backflow can also occur within a building and can be very dangerous, such as when a boiler with chemical additives is connected to the same water lines as a drinking fountain.