Voluntary installation requirements for supplementary water systems

Builders and property owners in any local government area can voluntarily install a rainwater tank or other supplementary water supply system (regardless of whether the local government has opted into the QDC).

All rainwater tanks or other supplementary water systems installed voluntarily must comply with the appropriate health and safety standards (regardless if the property is located within a reticulated town water area) under:

• QDC 4.2 – Rainwater tanks and other supplementary water supply systems (PDF, 51KB) – for residential buildings, covering Class 1, 2 and 10 buildings
• QDC 4.3 – Supplementary water sources (PDF, 70KB) – for commercial and industrial buildings, covering Classes 3 to 9 buildings.

A rainwater tank can be installed voluntarily to supply water for either:

• outdoor use only (e.g. gardening)
• both outdoor and indoor use (e.g. flushing the toilet or cold water for a washing machine).

Plumbing and building approvals

For an existing house or building where a rainwater tank is voluntarily connected for indoor use, the plumber must lodge a  Form 4 – Notifiable work (as it is plumbed to internal fixtures that have connection to the reticulated town water supply). A Form 4 is not required where a rainwater tank is for outdoor use only.

Local government planning scheme requirements may also apply for siting and boundary setbacks to correctly locate the rainwater tank on the property.

You may need a building approval to install a rainwater tank where the property is located in a tropical cyclone area (Wind Region C under AS/NZS1170.2 Wind Loading Code). Wind Region C covers the immediate coastal areas continuous from Bundaberg to the Queensland–Northern Territory border.

For non-cyclone areas, a building approval is only required where a rainwater tank is greater than 10m² in plan area and is more than 2.4m in height above ground. However, where it is smaller and shorter than these dimensions, it will not require a building approval.

It is recommended that you check with the relevant local government about any local requirements.

Use this installation checklist (PDF, 99KB) to assist with choosing a rainwater tank for your property.

Maximising the rainwater tank

By installing water efficient appliances and fixtures, such as a water efficient washing machine and toilets, water from the rainwater tank can last longer. Many household appliances and fixtures are star rated under the national Water Efficiency and Labelling Standards scheme (WELS). You can search for the star rating for household appliances and fixtures.

Also consider...

• Read the Queensland Plumbing and Wastewater Code.
• Download the rainwater tank information sheet (PDF, 1.2MB).
• Read Queensland Health's guide to keeping your rainwater tank safe (PDF, 849KB).
• Find out about rainwater on the Australian Government's Your Home website.