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Greywater use

Greywater (or grey water) is typically water from baths, showers, hand basins and washing machines. It does not include water from the toilet. Water from kitchen sinks and dishwashers is also technically greywater, however the high concentration of food wastes and chemicals mean that it is less suitable for re-use.

Should you reuse greywater?

Using greywater may be the only solution for keeping gardens alive during periods of hot, dry weather. Greywater replaces the need to use mains water for watering gardens or lawns and can potentially save thousands of litres of drinking water a year.

Benefits of using greywater:

Decreases your water bills.

Reduces the amount of sewage discharged to the oceans or rivers.

Irrigates your garden during drought periods.

Can be used to keep gardens alive when water restrictions prevent the use of mains water.

Greywater Do's and Dont's

The following list covers some of the major do's and don'ts when using a greywater system and is applicable to all residents in Australia. For further information, contact your local council or water retailer.

Use low phosphorus detergents
Diverted greywater (untreated) should only be used on the garden and not always in the same spot
Apply diverted greywater to the garden by a below ground seepage pipe. This will reduce human exposure to the water.
Use greywater only during prolonged warm, dry periods: use only what you need to meet the plant's water requirements
Ensure greywater is diverted to the sewer during wet periods
Install a diversion system that is 'fail-safe', where the greywater will automatically be diverted to the sewer if the greywater system blocks or malfunctions
Stop using greywater if you smell odours and your plants do not appear to be healthy
Wash your hands after watering with greywater and after gardening in greywater irrigated areas
Use less fertiliser when irrigating with greywater
Ensure greywater does not contaminate any source of drinking water: extreme care must be taken to ensure there is no cross-connection between the greywater re-use system and the drinking water supply

Don't

Never water vegetable gardens if the crop is to be eaten raw
Never use greywater that has faecal contamination, for example, wastewater used to wash nappies
Never store untreated greywater for more than 24 hours
Never drink greywater or allow children or pets to drink or play with greywater
Never allow greywater to flow beyond your property boundary or enter stormwater systems
Do not use kitchen wastewater (including dishwashers) - it contains highly concentrated food wastes and chemicals that are not readily broken down by soil organisms
Do not allow greywater to pool or stagnate as this will attract insects and rodents, which may transmit disease.

Greywater systems, permits, costs and rebates

Greywater systems vary greatly in price, depending on the complexity of the system and the intended end-use for the water. A simple diverter can cost under $100, while complete treatment systems can cost several thousand dollars. For further information on systems and prices visit our product library.

The permits required to install a greywater system and costs and rebates that apply vary according to where you live. For further information, contact your local council or water retailer.