Backflow Prevention

Every day, we rely on clean, safe drinking water. But did you know that without proper protection, contaminants can flow backward into the water supply? This silent risk is known as backflow and preventing it is one of the most important safeguards in plumbing and public health.

Council is committed to protecting the safety of our drinking water supply. Maintaining a robust and effective backflow prevention system is a critical part of ensuring our drinking water remains safe for consumption.

Where to start
Responsibilities
Removing a device

What is Backflow

Backflow prevention refers to measures that stop the reverse flow of water from a polluted or contaminated source into drinking or bathing water systems.

Backflow can happen when the normal direction of water flow is reversed. This can occur in two ways:

  • Back Pressure—when downstream pressure becomes greater than the supply pressure.
  • Back Siphonage—when supply pressure drops, pulling water back into the system like a vacuum.

Either situation can allow chemicals, bacteria, or other pollutants to enter drinking water.

Installing an appropriate backflow prevention device effectively manages this risk. A range of device types is available to suit different applications and site conditions.

Where to start

Backflow prevention starts within a property boundary by isolating a possible contamination source. These include irrigation systems, fire hose reels, commercial kitchens, processing plants, and trade waste areas.

Examples of potential source of contamination:

  • Fire Hose Reels (FHR)
  • Taps for cleaning Grease Traps
  • Irrigation
  • Swimming pools
  • Vehicle maintenance pits
  • Ornamental ponds
  • Air conditioning towers
  • Vehicle/bin washing bays
  • Chemical injection areas

Examples of properties requiring backflow prevention:

  • Hotels, Motels and unit complexes
  • Mechanics and vehicle repair workshops
  • Shops and Restaurants
  • Caravan parks
  • Medical and dental surgeries
  • Car and plant washing facilities
  • Dry cleaners and laundries
  • Hospitals and funeral parlours
  • Club houses for sports
  • Schools, day care centres and kindergartens
  • Pest control and water carrying vehicles
  • Garden with irrigation systems

Responsibilities

In Queensland, local governments are legally required to maintain a register of all testable backflow prevention devices under Section 101 of the Plumbing and Drainage Regulation 2019.

The section mandates that Councils must keep a register of every testable backflow prevention device installed within their area and monitor ongoing maintenance and testing of each device. This is crucial to ensure Council has accurate records of device locations, maintenance history, and can manage risk across the network in accordance with Council’s Drinking Water Quality Management Plan.

If your property has a backflow prevention device, it is important to know your role.

Property owners must ensure their devices are installed, maintained, and tested at least once each year. All backflow prevention devices must be tested by a person who is licensed to do the work and holds the correct Backflow Prevention endorsement on their plumbing licence.

All new devices must be registered with Council upon installation. Failure to fulfil your responsibilities may result in compliance enforcement action.

Plumbers working with backflow prevention devices must:

  • Be licensed to do the work and hols the correct Backflow Prevention endorsement on their plumbing licence.
  • Provide test results to Council and the owner within 10 business days using the approved Form 9.
  • Repair or replace any failed device immediately or isolate the outlet if repairs cannot be completed right away.
  • Notify council of any new, replaced, or removed devices as part of required reporting.
Form 9 here

Removing a device

In some instances, you may have a backflow prevention device that is no longer required.

If a licensed plumber confirms there is no longer a risk to the drinking water supply, the licensed plumber can remove the device. A Form 9 must be lodge with Council and a Form 4 with the Queensland Building and Construction Commission (QBCC) advising of the removal.

Council requests the licensed plumber to include a copy of the Form 4, along with the Form 9 for our records.

Once Council has received an advice of removal,  an inspection will be conducted on site to confirm that the water supply is safe. Council will then proceed to update the register, and you will no longer be charged the annual fee.

If you have any questions in regards to backflow, please do not hesitate to contact the friendly plumbing team 07 4099 9444 or email enquiries@douglas.qld.gov.au.

Form 4 here

Register of backflow prevention devices

Council is required under the Standard Plumbing and Drainage Regulation 2003 Section 38 – Testable backflow prevention devices, to keep a register as per the following:

  • 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.
  • An owner of an installed testable backflow prevention device must-
    • register the device with the local government or entity; and
    • at least once each 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.

Locating a licenced plumber

You can locate a licensed plumber in the local phone book under “Plumbers”. Ensure the licensed plumber has the appropriate endorsement to undertake such work.

Annual fee

This is an administration fee to cover the costs to maintain an up-to-date register. Please see Fees and Charges Schedule for current fees.