What is backflow testing and why do you need it?

backflow testing Blue Mountains
Backflow testing Blue Mountains & Penrith

What Is Backflow Testing?

We can’t describe backflow testing without describing backflow. Backflow occurs when pressure fluctuations affect the unidirectional flow of water on your property, causing your used water to mix with the clean one. In essence, people with commercial properties might contaminate the clean, unused water, which might lead to poisoning. This is not common, but it does happen, so there is a need for backflow testing.

Backflow testing is a means of testing for backflow. It is a quick way of checking if your used water is mixing with the used, dirty water from your property. A plumber uses a backflow testing device to check if there is backflow and why it is happening.

Why Would Someone Need Backflow Testing In Australia?

Backflow testing is important because it helps you determine the quality of water you and everyone else are drinking. Considering how important water is, contaminating it can quickly become a widespread problem. Backflow testing is essential for commercial properties because they are the most likely to be working with chemicals that might contaminate the water supply.

Some commercial properties need to dispose of potentially dangerous chemicals, and if these chemicals find their way into the water system, it might be difficult to cleanse the water of these chemicals. For this reason, annual testing of backflow devices is necessary. A property owner has to ensure that backflow testing is carried out annually on their property, or it might have legal implications.

What is the Backflow Testing process like, and how much time does it take?

When testing the backflow in a commercial property, you need to hire licensed plumbers. The plumber hired needs to be licensed, and there are additional courses the plumber has to do, even after they have gotten their plumbing license before they are accredited to carry out backflow testing.

Before the process is carried out, the property owner or occupant are notified of the water supply shut down. They will inspect your property and understand your water supply and the arrangement of the backflow testing devices installed. They will also consider the make and model of your backflow system, record the serial number and location, and start the testing process.

The plumber will test your backflow system. If it passes the test, the plumber will log onto Sydney Water and acknowledge that the system is in full working order. However, if the system fails these tests, it implies that there are areas of backflow, and the plumber has to repair the system. Once the system has been repaired, the plumber will log onto Sydney Water and state that the system is repaired and is in full working order.

This process is mandatory for every commercial property in Australia, and they have to call a plumber and schedule them for the process. The good news is that this process is not complicated at all. It does not require that much time and unless the property has more than one backflow testing device, the entire process should be completed in half an hour.

How much does Backflow Testing cost?

The price for backflow testing depends on many factors, including the size of the system and the number of backflow devices installed. However, the price is usually somewhere between $285-$320. This price also includes the fee that the plumber has to pay for logging in the test results into the Sydney Water portal.

Types of Backflow Testing Devices

A backflow device is a generic term for all the devices and systems used to protect your water system. These devices are divided into those that are testable and those that are non-testable, but for this piece, we are going to stick to the testable devices.

There are three types of testable backflow devices, and they include:

The Reduced Pressure Zone Device (RPZD)

This device checks for negative pressure on the inlet side of the water system. This is a sign of water backflow. It has a spring inside that closes the water off when backflow is detected and dumps it, thereby preventing backflow.

The Double-check Valves

The double-check valves are like the reduced pressure zone devices. It is made up of the valve body, two independent check valves, and an inlet shutoff valve. They are different from the RPZD because they do not dump the water, but they are excellent for preventing backflows.

The Registered Air Gap

This testing device is for high-rise commercial buildings with water tanks on their roofs. The registered air gaps check that these tanks are still functioning.


Backflow testing is important because backflows can cause a lot of problems. It is a compliance item for all commercial properties, including daycares, nursing homes, and schools. It is a simple and necessary process to protect Sydney Water.

Ironclad Plumbing provides a full range of commercial and residential plumbing services in the Blue Mountains, Penrith and Lithgow. Get in touch today!

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