Backflow prevention devices stop water flowing the wrong way. They're used to protect the public drinking-water supply and to protect people living or working inside buildings and properties.

Did you receive a letter from us about backflow prevention?

You may need to install a backflow prevention device at your property or let us know about an existing device. 

Please complete our backflow prevention devices online form(external link) to:

  • let us know which installation option you’ve chosen; or
  • to notify us of an existing device; or
  • to get in touch with us.

We’ll email you back within 10 working days, usually sooner.

This section applies to you if you recently received a letter from us about backflow prevention and you’ve chosen to self-manage the installation of only a backflow prevention device at your property’s boundary (‘Option 1’ in the letter you received).

For any other situation, such as:

  • you want to install a backflow prevention device as part of other building work
  • you didn’t recently receive a letter from us about backflow prevention at your property

You need to apply for building consent in the normal way. Please refer to the section below titled ‘Installing a backflow prevention device’.

Fees

We’ve streamlined the building consent process if you’re only installing a backflow prevention device – a fixed fee of $430 (incl. GST).

Your streamlined building consent will be approved within two working days of receiving your application, provided you’ve supplied all necessary information.

Please note that the fixed fee may not always cover all of the consent-related costs of an application (e.g. if the application does not contain all necessary information).

Process

1. Let us know 
You need to let us know(external link) that you’ve chosen to self-manage the installation of your backflow prevention device (‘Option 1’ in the letter you received). 

We’ll email you within two working days with the information and documents you need.

2. Apply for a building consent 
Complete and submit an Application for a building consent for the installation of a backflow prevention device (Form B-009) [DOCX, 396 KB]

3. Install your backflow prevention device 
Once your consent is approved, a certifying plumber can go ahead and install your backflow prevention device on the private side of your property’s boundary. 

After the device is installed, you may notice a small drop in water pressure. This is a sign that the device is working properly.

4. Apply for a code compliance certificate
After your backflow prevention device has been installed, you need to apply for a code compliance certificate using Form B-011 [PDF, 206 KB]. The cost of this is already included in the streamlined building consent application fee. 

When you apply for a code compliance certificate, you also need to include the following information:

We’ll then issue you with a code of compliance certificate with a compliance schedule (or an amended compliance schedule) for your building.

5. Get your device tested annually
Your device needs to be tested annually (or after any repairs) by an IQP, as required by the compliance schedule, for you to be able to issue the annual building warrant of fitness.

You need a building consent from us before you can install a backflow prevention device. But if you've already applied for a building consent for other work, you can include your device in the same application.

To apply for a building consent for a backflow prevention device, please complete and submit the following two forms: 

  1. Application for a building consent (Form B-002), available either as a Word Doc [DOCX, 425 KB] or PDF [PDF, 257 KB].
  2. Backflow prevention device check sheet [PDF, 96 KB] (Form B-052). 

Please refer to the Building Consents fees  for more information.

Please note that the fixed fees and minimum application fees do not always cover all of the consent-related costs of an application (e.g. if the application does not contain all the required information).

A typical backflow prevention device for 'high risk' protection.

The property owner is responsible for the costs of installing, maintaining and testing any backflow prevention device. Costs for installation vary widely and depend on the:

  • degree of protection required (risk level)
  • size of the device
  • complexity of the installation

A certifying plumber must install a backflow prevention device and all testing of the device must be carried out by an Independent Qualified Person (IQP)(external link)

More information about backflow and backflow prevention.

A backflow prevention device is a specified system. Specified systems need to be included on a compliance schedule.

A backflow prevention device needs to be tested annually (or after any repairs) by an independent qualified person (IQP)(external link), as required by the compliance schedule, for you to be able to issue an annual warrant of fitness 

A building warrant of fitness confirms that your specified system has been inspected and maintained as required. Please see our compliance schedule webpage for more information about specified systems, compliance schedules, and IQPs.

How do I know if I need a backflow prevention device?
All commercial and industrial properties, other than those with a backflow risk similar to a residential house, are required to have a backflow prevention device installed. If you recently received a letter from us asking you to install a backflow prevention device, then you need to complete this online form(external link) and have one installed as soon as possible.

I recently received a letter from you about backflow prevention. What process do I need to follow?
Please use this online form(external link) to:

  • let us know which installation option you’ve chosen, or 
  • to notify us of an existing backflow prevention device, or
  • to get in touch with us.

We’ll email you back within 10 working days, usually sooner.

If you’re self-managing the installation of your backflow prevention device (‘Option 1’ in the letter you received), please refer to the section above titled ‘If you recently received a letter from us’.

Do residential properties need backflow prevention?
Yes, if there are any 'high' or 'medium' backflow risk activities occurring on-site. This includes hairdressers, swimming pools, spa pools, and irrigation systems with underground controllers. A certifying plumber can advise about your specific property.

Why do I need to install backflow prevention?
Backflow can cause water (and potentially chemicals and other contaminants) to be sucked or pushed back into the public drinking-water supply, potentially causing serious illness, injury or death. As a commercial or industrial property owner, you are legally responsible for preventing backflow from your property and for making sure you don't contaminate the public drinking-water supply.

I already have a device installed – what should I do?
If you recently received a letter from us but already have a backflow prevention device installed, then you need to let us know what devices are located on your property and the level of risk they protect against. Please use this online form(external link) to let us know.

What’s the difference between boundary backflow prevention and ‘zone protection’?
Protecting the drinking water within your property’s boundaries (e.g. within a building) is known as ‘zone protection’. This is a separate matter to protecting the public drinking-water supply, which requires a backflow prevention device at your property’s boundary. A boundary device prevents water from your property’s water pipes potentially back-flowing into the public pipes.

I own property but no building – do I still need a device?
If you don't intend to use water on your property, then you don't need to have a backflow prevention device installed. However, any use of water, even for irrigation, may mean you need a device. When applying for building consent to develop a property, backflow is considered as part of this application. If you don't need a water connection to your property, you can apply to have it removed.

I received a letter but my neighbour didn't – why?
It's possible they haven't yet received their letter from us, or their property wasn't deemed to be a risk to the public water supply network.

Can I choose not to install a device?
As a commercial or industrial property owner, you’re legally responsible for preventing backflow from your property and for making sure you don't contaminate the public drinking-water supply. If you don't meet these responsibilities, we may need to install a backflow prevention device at your cost.

If you recently received a letter from us about backflow prevention, please contact us using this online form(external link) or by phoning 03 941 8999.

For all other queries:

email backflowconsents@ccc.govt.nz.