What is backflow prevention?
Backflow prevention stops the reverse flow of water from a potentially polluted/contaminated source getting into the drinking water supply.
Backflow prevention starts within a property boundary by isolating a possible contamination source from the town water main or storage tanks (rainwater) to the tap or appliance.
This risk can be managed by installing a backflow prevention device.
There are a number of backflow prevention devices available to suit any particular situation.
How does backflow occur?
Backflow can occur through back-siphonage in a pipe via pipe breakage, undersized pipework or high withdrawal rates. It can also occur from back-pressure within properties, generated by elevation, thermal expansion or pumps.
Our water supply needs to be protected
All water supply systems intended for human consumption, food preparation, utensil washing or oral hygiene must be safeguarded from contact with contaminated water.
This applies to water services connected to Council's water supply or rain water tanks.
Possible sources of water contamination
Grease traps, sullage pits and process tanks, vehicle maintenance pits, vehicle washdown bays, air-conditioning towers, swimming pools and spas, fire hose reels, dishwasher/glass washers, chemical injection areas, ornamental ponds, bidets/bain maries, irrigation areas, marinas, boilers/steam pipes.
Examples of properties requiring backflow prevention
- Motels and unit complexes
- Catering and allied industries
- Vehicle repair shops
- Shops and restaurants
- Caravan parks
- Medical and dental surgeries
- Veterinary surgeries
- Car and plant washing facilities
- Dry cleaners and laundries
- Hospitals and funeral parlours
- Club houses for sports
- Industrial installations
- Schools, day care centres and kindergartens
- Pest control and water carrying vehicles
- Chemical storage plants
- Properties used for agricultural and horticultural purposes
- Zoos and local attractions
- Botanic gardens
- Railway stations.
- Properties with separate supply pumps
Who installs/tests backflow prevention devices?
Installation of backflow devices needs to be carried out by a licensed plumber.
Testing of backflow devices MUST only be carried out by a suitably qualified licensed plumber who is trained to comply with the following Australian standards:
- Plumbing and Drainage Act 2002
- AS/NZ 3500 national plumbing and drainage standard
- AS/1319 signs/occupational environment
- AS/1345 identification of the contents of pipes, conduits and ducts
- AS/2845.3 water supply backflow
- AS/3855 prohibited materials
- AS/4360 HB 143, risk assessment
- Standard plumbing and drainage regulations 2003
Application and registration of testable backflow prevention devices
Testable backflow devices require annual testing and are registered by the Cassowary Coast Regional Council.
Council is required to keep a register as per the following:
Standard Plumbing and Drainage Regulation 2003, Section 38 – Testable Backflow Prevention Devices
- A local government must implement and maintain a program for its local government area for the registration, maintenance and testing of testable backflow prevention devices installed in the area.
- The local government, or an entity authorised by the local government, must keep a register of the testable backflow prevention devices.
- An owner of an installed testable backflow prevention device must:
- register the device with the local government or entity; and
- at least once a year have the device inspected or tested by a person who is licensed to do the work.
- A person who inspects or tests a testable backflow prevention device must, within 10 business days after inspecting or testing the device, give the local government written results of the inspection or test.
When submitting annual test reports, please post to:
Cassowary Coast Regional Council
PO Box 887
An application to install a testable backflow prevention device needs to be made to Council's Building Department. A Form 4 needs to be submitted to Council for all valve replacements.
Businesses will receive an annual reminder letter for compliance. Failure to comply will attract a penalty of up to 20 penalty points ($2,000).