Backflow Prevention System Application: What to Know

When you’re managing a home or commercial property, protecting your water supply is crucial. At All Needs Plumbing, we specialise in helping homeowners and business owners across Sydney and beyond with the proper backflow prevention system application to keep water safe and compliant. Knowing the difference between a backflow preventer and a check valve can save you a lot of money and health issues in the long run. Here’s what you need to know.

Understanding Backflow and Why Prevention Matters

If water flows backwards through your plumbing, it allows dirty water to enter your clean water supply. This is called backflow. This may occur due to back pressure or back-siphonage. Back pressure occurs when the pressure in the system exceeds the supply pressure. Both situations pose serious risks because they can introduce chemicals, bacteria, or other pollutants into your drinking water. For commercial properties and homes alike, preventing backflow is not just about compliance—it’s about protecting health and safety.

What’s a Check Valve?

A simple mechanical device called a check valve only allows water to flow in one direction, preventing it from flowing backward. You’ll find check valves in irrigation systems, sump pumps, and some general plumbing applications. They’re affordable and straightforward to install, which makes them popular for low-risk situations. However, check valves provide just one layer of protection and can fail if debris blocks them or if they wear out over time. If that happens, backflow can still occur, potentially contaminating your water supply.

Pro-Tip: If your system is low-risk and non-potable—like garden irrigation or stormwater—you might get away with a check valve. But always have a professional plumber assess your setup to avoid surprises.

What’s a Backflow Preventer?

A backflow preventer is a specialised device designed to stop contaminated water from entering your potable water supply. Unlike a check valve, it has multiple safety mechanisms—such as double check valves, atmospheric vents, and relief valves—that work together to ensure water only flows in the right direction. These devices are essential in commercial buildings, irrigation systems, fire protection systems, and other areas where the water supply is vulnerable to contamination.

In Australia, backflow preventers are required by law in medium- and high-risk situations. These devices can only be installed and tested by licensed plumbers to ensure they meet strict safety standards.

I once helped a café owner who assumed a check valve was enough. Following a professional inspection, we installed a backflow preventer to comply with regulations and protect their customers. It gave them peace of mind and ensured compliance with local laws and regulations.

Key Differences: Check Valve vs Backflow Preventer

When Should You Use Each?

Use a check valve for low-risk, non-potable water systems such as irrigation or stormwater pumps. However, when it comes to protecting your drinking water, especially in commercial or high-risk settings, a certified backflow preventer is essential. It’s not just a recommendation—it’s a legal requirement in many cases, and it keeps your water safe for everyone.

Pro-Tip: Don’t guess your risk level. Have a licensed plumber assess your property and recommend the appropriate backflow prevention system for your specific needs.

Installation Considerations

Backflow preventers require professional installation and regular testing to ensure they work correctly. Licensed plumbers follow Australian standards and use specialised tools to install and maintain these devices. Check valves are simpler but still need to be fitted correctly to avoid future problems.

FAQs About Backflow Prevention System Application

Where should a backflow preventer be installed?

Backflow preventers should be installed at cross-connection points, where your potable water supply could be contaminated with contaminated water. This is usually where the main water line enters your property or connects to irrigation systems, fire sprinklers, or commercial appliances.

Can you put a backflow preventer on a sewer line?

While you can install a backflow preventer on a sewer line, it’s more common to use a backwater valve for this purpose. When there is a blockage or a lot of rain, backwater valves stop sewage from flowing back into your property.

Do you need a backflow preventer on a house?

If your home has connections that could allow contaminated water into the main supply—such as irrigation systems, rainwater tanks, or fire sprinklers—you likely need a backflow preventer. Local regulations vary, but it’s essential for safety and compliance.

Where should a backwater valve be installed?

A backwater valve is put on the main sewer line that leaves your property. This is typically done in the basement or underground to prevent sewage from backing up into your building.

How do I know if my house has a backflow preventer?

Look near where your main water line enters the house. You might see a device with test cocks and shutoff valves. If you’re unsure, call a licensed plumber to inspect and confirm.

What if I want to know more about the backflow prevention system application?

If you want to understand more about which backflow prevention system application fits your property or need expert advice on compliance and safety, we’re ready to help. At All Needs Plumbing, we offer a $0 callout fee, 24/7 same-day service, a 15% seniors’ discount, and $150 off hot water systems. We’re here to keep your water safe and your plumbing compliant without any hassle.

Contact us today and let’s get your backflow prevention sorted by professionals you can trust.

Available 24/7 For Emergency

1300 110 230 Get a Free Quote