Supply options
At household level
Bucketing is a simple method to collect greywater directly from the bathroom and laundry with a bucket and apply it evenly on garden or lawn areas.
Greywater diverters are usually gravity diversion devices that coarsely filter greywater. This method only allows greywater to be used for irrigation below ground to reduce the risk of human contact. There are a number of products on the market that range in price depending on their complexity. The filter system generally requires regular maintenance by the homeowner.
Greywater treatment systems collect, store, treat (chemically and/or biologically) and may disinfect greywater to the standards specified by the Department of Health. Depending on the level of treatment, this enables the use of treated greywater for above ground irrigation, toilet flushing and cold water supply to washing machines. Treated greywater can be stored for longer than 24 hours, unlike untreated greywater.
All greywater diversion and greywater treatment systems have to be approved by the Department of Health and must be installed by a licensed plumber.
At community scale (buildings and new residential developments)
There is growing interest in the collection of greywater from a new office or apartment complex for on-site treatment and reuse in the toilets of that building or watering of small on-site green spaces. The quantities of greywater produced and the intended reuse will depend on the purpose of the building – residential or commercial. A water service provider may be required to provide the service.
New urban developments may include decentralised or centralised greywater reuse options.
Decentralised greywater reuse
This option involves individual treatment systems at each new home, managed directly by the householder. It is important that information or assistance is provided to householders on the use of suitable cleaning products and appropriate operation and maintenance of the greywater reuse system.
Centralised greywater reuse
This option involves greywater being treated at a centrally located treatment system and distributed back to households. A water service provider is required.