What is a Backflow?

In water supply systems, water is maintained at a significant pressure to enable it to flow from the tap, shower etc. When this pressure fails or is reduced – due to a possible burst water main, frozen pipes or there is unexpectedly high demand on the water system – the pipe may allow contaminated water from the ground, storage or from other sources to be drawn up into the main system. By definition, a backflow is an undesirable reversal of flow of a liquid, gas or solid into the potable water supply. A Backflow Prevention Device keeps this from happening.

Backflow Prevention Devices:

A simple and effective way to provide backflow prevention, is to provide an air gap. An air gap is an open space between any device that connects to a Plumbing system (like a valve or faucet) and any place where water can collect or pool.

Alternatively, a specialized backflow prevention valve may be installed at strategic locations in the plumbing system wherever there may be a risk of contaminated fluids entering the water supply. A check valve is a common form of backflow prevention, but more complex devices may instead be required.

Backflow Testing & Maintenance:

Registered Backflow protection devices must be tested as follows:

  • Immediately after installation;
  • Annually (at intervals not exceeding 12 months);
  • On completion of maintenance work;
  • After a Backflow or suspected Backflow incident;

The property owner is responsible for ensuring that the backflow prevention device is tested following these occasions by an approved certifier.

Backflow Prevention – Supply & Installation:

There are three types of Backflow protection installation methods. One or all methods may be used, depending on the backflow prevention requirements of the property.

  1. Containment protection – device installed at the property boundary, just downstream of the meter assembly serving the property, including all fire services located at the boundary.
  2. Individual protection – device installed at point of potential contamination within the property.
  3. Zone protection – device isolates an area or building within the property.

The installation of a containment backflow prevention device does not eliminate the need for individual and zone protection devices. Water downstream of a containment device is considered non-drinking water if there are internal backflow hazards remaining within the property. In these situations, the installation of an individual and/or zone device will be necessary to protect against further potential risks.

A licensed Plumber must install, commission and test all Backflow Prevention Devices. If the property has multiple new or relocated water services you will need suitable backflow prevention at the connection point for each service. Connections are not permitted between the meter outlet and the containment device. Backflow Prevention Devices must be accessible for maintenance and testing and must not be buried or installed in a pit or chamber.

For your Backflow Prevention testing and maintenance, please call the experienced team at AR Lake Plumbing now on 0408 294 801.