Rainwater tanks and greywater systems

The south-west of Western Australia is facing challenges caused by a drying climate, population growth and reduced groundwater availability, to the extent that it can no longer rely on traditional water supplies to meet the community's demands for water.

The Town of Victoria Park supports the use of alternative water sources, such as installation of greywater systems and rainwater tanks, where it is socially acceptable, economically viable and environmentally sustainable to do so. The Department of Health (DoH) regulates the installation of such systems within WA.

Below provides some guidance on greywater and rainwater tank installation, in accordance with DoH guidelines.

Greywater

Greywater is used household water sourced from baths, showers, bathroom basins and laundries, but excludes water from the toilet ('blackwater'). Greywater reuse systems can vary in complexity and can be categorised into two main areas: untreated (bucketing and greywater diversion) and treated (greywater treatment systems). The majority of greywater reuse is at the household level.

Find out more about greywater:

Department of Health

Water Quality Australia

Greywater and Wastewater Industry Group

Rainwater

Rainwater is water harvested directly from roof runoff from domestic or commercial buildings and captured in rainwater tanks. Rainfall is variable in Perth, so to optimise the full potential of rainwater as a water source, the rainwater system should be plumbed into the building for non-drinking purposes, such as in laundries and toilets.

On average, a roof area of 100 m2 (approximately 50% of an average house in Perth) can collect about 50,000 litres of water a year when plumbed for internal and external use. With an appropriately sized rainwater tank, this could supply up to 20% of a household's water needs.