SHADES OF GREYWATER

Learning how to use greywater opens up even more water-conserving opportunities

- KAREN SUTHERLAND

In many households, greywater is a large and untapped resource. Reusing at least some of your waste water on site fits in with permaculture principles, reducing your impact on the environment as no resources are being used to process it off-site. For the many areas of Australia that have been in drought for years, with garden water availability either limited or curtailed, greywater may be the only way to have a garden.

Of course, there are caveats. The regulations governing the use of greywater vary considerably, so check with your local council to make sure its use is permitted in your area. Some areas allow diverted greywater to be used; others only greywater that has been through an approved treatment system. Also, remember that greywater should not be used if there is no need for irrigation normally.

Another commonly asked question is whether greywater can be used on veggies, herbs or fruit trees. The answer lies in gaining an understanding of what greywater is and how it can be safely used.

WHAT EXACTLY IS GREYWATER?

Greywater is waste water from the laundry and bathroom (that is, the bath, shower, handbasin or final rinse of the washing machine). The toilet is classified as black water and in Australia, kitchen waste water is also usually classified as black water. It’s not advisable to reuse the water from hand basins and laundry troughs (unless it’s been treated) as it contains many substances not suitable for gardens.

An often overlooked resource is the water saved while warming up the shower, washing fruit and vegetables before eating and vegetable and pasta-cooking water. It is possible to save at least 20 litres of this water a day for reuse on pots, herbs and vegetables and this amount can keep a small vegetable patch alive. The water from rinsing soap from clean dishes is also suitable for use in this way.