By using a non-potable water supply as an 'alternative water source', where appropriate, it is possible to significantly reduce the amount of potable water used by your development. Alternative water sources are optional, but in most cases a dwelling will need to nominate an alternative water source to achieve the required water target.
Types of alternative water
Different types of alternative water require varying levels of treatment and the uses permitted for an alternative water source will vary depending on the type and the treatment method selected.
BASIX recognises the following alternative water sources:
- Rainwater– collected from roof areas and stored in a rainwater tank
- Stormwater– collected from trafficable surfaces and stored in a stormwater tank
- Greywater– diversion and treatment systems can be used to collect and re-use wastewater from the bathroom and laundry
- Private dams (single dwellings only)– for toilet flushing, laundry, and garden irrigation
- Reticulated recycled water– recycled wastewater supplied by a water authority or central authority via a reticulated system to individual lots for non-potable use
- Central on-site recycled water systems (multi-dwelling developments only)– for toilet flushing, laundry, and garden irrigation
- Hot water recirculation and diversion– collecting water from hot water fittings until the water reaches the desired temperature
BASIX does not recognise groundwater, river water or on-site sewage management systems as alternative water sources. Please refer to sources not recognised by BASIX for further information.
Water uses
For each water use in the development, you must nominate a water source. The source may be mains-supplied potable water or one of the recognised alternative water sources.
Acceptable uses can include:
- garden and lawn
- toilets– only if all toilets are connected
- laundry
- hot water– only if all hot water uses the alternative water source
- household uses– only if all water uses the alternative water source
- pool and spa top-up
- cooling tower make-up water