Recycling grey water around the home

More and more people are looking to beat the water restrictions and maximise our precious water resources by reusing their bathroom and laundry grey water.

What is grey water exactly?

"Grey water is water from the bath, shower, hand-basin and laundry washing machine, which many people use to keep their gardens and lawns looking good during the extended drought period," says Leon Stackpole, from the Environmental Protection Agency (EPA) Victoria.

According to Sydney Water, an estimated 61 per cent of an average household's water can be used as grey water, accounting for more than 350 litres a day. This does not include water from the toilet, known as black water, which cannot be reused, or kitchen waste water, which should be avoided due to the fats and solids it contains.

Which grey water is the best?

The most suitable grey water comes from your bathroom, or the washing machine rinse cycle. Washing water can also be used, but you need to use a low-salt, phosphorous-free detergent. Water used for washing dirty nappies or animals should never be used.

What is a diverter system?

Diverter systems can be as simple as bucketing the water onto your garden or fixing a hose to the outlet pipe on your washing machine. More complex systems must be installed by a plumber, but can make life much easier, with water automatically being diverted through pipes to your garden.

How can I divert grey water straight to my garden?

"Those looking to divert the water straight onto the garden can do so with simple diverter systems available from the hardware store, while those looking to store the water for more than 24 hours must use an EPA-approved system and contact their local council to obtain a permit," says Leon.

When diverting grey water to your garden, keep in mind that it should only be used for watering plants, shrubs and lawns, not vegetables that are consumed raw.

When do I have to use grey water by?

Untreated grey water must be used within 24 hours, as it contains bacteria that can cause an offensive smell. For those who are serious about getting the most from their grey water, treatment systems are available that allow you to store the water for a longer period. This means you can use it for flushing toilets and washing clothes.

There have been no long-term studies into the effects of grey water on gardens, so it's important to monitor the health of your plants and, if you notice any adverse effects, rest the area for a while.

Contact a grey water expert in your area to find out how you can use grey water around the home: