Grey water is waste water from washing machines, kitchens, showers, basins and baths. It excludes water from toilets or bidets.
Grey water can be used to water gardens and lawns and if treated, to flush toilets and wash clothes - and you can use as much as you like, since it's not subject to water restrictions.
Just by watering your garden and lawns with grey water, you can cut up to 100,000 litres of drinking water use each year!
There are generally two types of grey water use - direct diversion or a grey water treatment system. Direct diversion is the cheaper option - about $2000 - whereas a full treatment system can cost around $10,000.
It's illegal to pipe grey water directly onto your garden without using direct diversion or a treatment system. This is because grey water contains bacteria which can be a health hazard if not properly managed.
Although Council approval is no longer needed for most homes, you will need a licensed plumber to install a direct diversion or a treatment system so you can use grey water. You should also check with the EPA that your preferred option meets their requirements.