Greywater and rainwater
Using alternative water supplies safely in your home and garden.
Using a diverse range of water sources improves the security of our water supply. When used safely and according to regulations and environmental standards, alternative water sources can help protect our environment.
The permanent water saving rules and water restrictions do not apply to greywater, rainwater and recycled water – unless supplemented by the mains water supply. This includes rural water users and domestic and stock water usage.
Greywater is wastewater from non-toilet plumbing systems such as bathroom sinks, washing machines, showers and baths. It doesn’t include water from toilets. That is blackwater which may contain pathogens that spread disease.
If you grow vegetables or fruits that are eaten raw, these plants should not be watered with greywater. Do not use greywater as drinking water. See Safe drinking water.
You must use greywater carefully. This includes treating and disinfecting it before use. If it’s not used properly, it can make people and animals sick and kill the plants in your garden.
Greywater containing kitchen wastewater requires a greywater treatment system that is certified to handle kitchen wastewater. Greywater treatment systems may require a council permit.
Greywater can be a good option during times of drought and water restrictions. The safest greywater is from the rinse cycle in your washing machine. Water from the wash cycle is the next safest, followed by bath or shower water.
Greywater can be useful for:
- garden watering, with precautions – for example:
- Use garden-friendly, biodegradable detergents, soaps and shampoos.
- Use cleaning products that are low in salt and phosphorous.
- Apply greywater to plant roots – below the soil surface.
- toilet flushing and clothes washing, if the greywater is properly treated.
We recommend that you display a sign if you use greywater to water your garden.
For guidelines on using greywater, see:
- Victorian Environment Protection Authority (EPA) – About greywater
- Australian Government Your Home website – Wastewater reuse.
Capturing rainwater from your roof is a great way to supply water for your home. It is a good source of water for washing clothes, flushing toilets and watering your garden.
It is recommended that you do not use rainwater for drinking and food preparation. The quality of water in household rainwater tanks is generally not as reliable as mains water supplies, which have been treated to be safe for human consumption. See Safe drinking water.
For guidelines on using rainwater, see:
- Victorian Environment Protection Authority (EPA) – Alternative water sources and their use
- Australian Government Your Home website – Rainwater.
Installing a rainwater tank
Before purchasing or installing a rainwater tank, make sure you:
- choose the right tank for your needs
- organise installation and maintenance
- check the health, building and/or council regulations in your area
- make sure the tank meets relevant Australian standards
- ensure safety and water quality.