Grey water is the waste water stream from all sources other than the toilet and kitchen because this water contains sewage, oil, fats and food scraps which will not break down easily and will cause blockage in filters and pipes. Most houses can easily re-use Greywater from their laundry’s and bathrooms to water the garden.
On average an Australian household will use 700-800 litres of water per day. This equals about 300,000 litres of water a year, and 40% of that use is on gardens. Water is a very valuable, scarce resource in Western Australia, this is why any endeavour to reduce freshwater consumption or to reduce wastewater disposal is encouraged.
What do you need to know about Greywater?
Any Greywater system must be approved by your local government and a licenced plumber is required to make any changes to the sewer system
The Greywater needs to first pass through a filter and/or settling tank before reuse. The filter will remove any coarse materials (i.e. hair, soap, sand)
Greywater cannot be used to water root-crop vegetables (i.e. carrots) but can be used on above ground food and fruit crops, lawn and other plants.
An overflow safety device and diverter valve needs to be installed to divert Greywater back into the sewer line or into a wastewater treatment system.