Greywater recycling

Greywater can be used to supplement your household and farm’s water supply. Greywater includes wastewater from plumbing systems, such as hand basins, washing machines, showers and baths, but not the toilet (blackwater). In the home, it can be used for laundry and toilet flushing. Outside of the home, greywater can be used to water garden plants (but not vegetables), wash machinery and vehicles, and keep dust down around the house.

Things to consider

Unless you have a proper treatment facility you should not store greywater (over 24 hours).

You can use greywater in three ways:

  1. Manual bucketing – collecting water in a bucket (eg. from the washing machine or shower and watering the garden). This is the cheapest option.
  2. Greywater diversion – these systems divert greywater to a small holding tank and then to an irrigation system below the soil surface.  
  3. Greywater treatment – these systems clean greywater enough to be stored and can be used in any weather. It is not clean enough to drink but can be used to flush toilets, wash clothes and water the garden.

Two key benefits of using greywater include the reduced need for freshwater and the reduction in the amount of wastewater entering sewers.

Take care when using greywater. It has the potential to make people in your household unwell and kill plants. Make sure farm animals and pets don’t drink it and that it doesn’t run into creeks or other waterways. There are also biodegradable washing products that make your greywater safer to use.

Find out more about this topic on Better Health Channel

Fast facts:

  • Greywater from basins, washing machines, showers and baths can be used. Do not use water from toilet systems.
  • Use greywater with care. Don’t store grey water; use it immediately on your garden or for washing cars or farm vehicles.
  • Make sure greywater does not run or leech into creeks, dams or other waterways and do not use it for stock or other animals.
  • Check your local greywater regulations as they differ around Australia. 

References used for this topic

More information:

Department of Sustainability, Environment, Water, Population & Communities
Guidelines for developing recycled water schemes in horticulture

Sustainable Earth Technologies
Grey Water Treatment

Better Health Channel
Greywater – recycling water at home

Research & reviews:

Journal of Water, Air and Soil Pollution
Reuse of domestic greywater for the irrigation of food crops