free website hit counter code


Backflow, Explained

The water supply system is designed to ensure that water flows to your property under pressure. There is a risk to public health if there is a cross connection between your water supply and a contaminated source. If there is a pressure drop in the water main, a vacuum could be created in the water supply system. Under certain conditions this creates a siphoning effect and draws liquid from a contaminated source back into the drinking water supply.

Water pressure can be affected when:

  • there is a break in the water main
  • water is being pumped from the main water supply during a fire
  • a customer is using water at a higher pressure than the pressure supplied.
  • heavy water use downstream reduces water pressure upstream
  • the water outlet at the property is higher than the water main, causing constant back pressure.

A number of different property types pose a particular risk through cross connections.

These include:

  • chemical plants
  • pest controllers
  • market gardens
  • golf courses/sporting ovals
  • caravan parks
  • greywater treatment systems
  • metal processing plants
  • paint manufacturers
  • laundries
  • nurseries
  • residential properties with rainwater storage.

If your site needs surveying for cross connection call us for a consultation.