Grey water

As we consider ways of saving water, one important method is using more grey water, which basically means using the same water more than once. There are risks and concerns around grey water use, which is why users of grey water must be careful to make sure grey water does not get confused with clean, safe drinking water. However, there are many ways we can use grey water, which greatly improves our water saving ability.

• Grey water is the wastewater collected from your basins, showers, baths, spas, laundry and kitchen. The safest, or cleanest, grey water comes from the shower, bath and washing machine.
• Grey water does not include blackwater from toilets.

• Yes, grey water is safe when guidelines are followed and it used for its intended purpose.
• Primarily, the use of recycled water is governed by the NSW Guidelines for Grey water reuse in Single Household Residential Premises. This document provides guidance for the correct and safe use of grey water, there are additional guidelines for multi-premises and commercial premises.

• Residential households can use less clean drinking water if they use grey water for some of their needs (meeting the requirements of BASIX).
• Reduces demand on drinking water which helps conserve water resources and reducing the discharge of effluent to waterways.
• Cost saving benefit in using grey water over potable water.
• Grey water is available all year round

• Currently there are two types of grey water systems that are approved for sewered single domestic premises; grey water diversion devices and domestic grey water treatment systems.
• Grey water diversion devices are installed to redirect grey water to the garden or lawn via a sub-surface irrigation system. Approval is no longer required from your local council to install a grey water diversion device; however a licensed device must be used and a certain criteria must be met.
• Grey water treatment systems collect, store, treat and may also disinfect grey water to a higher standard grey water to be used in more ways.  The installation and operation of grey water treatment systems require local council approval and registration with NSW Health.
• Hunter Water supports the reuse of grey water by households. However, it is not our role to supply information on installing, treating and using grey water devices and treatment systems within your household. Our view notes that many grey water and rainwater recycling systems are plumbed back to toilet and/or washing machines have a potable water top-up capacity to ensure tanks do not run dry. This raises the risk of cross contamination, which we believe should be prevented by installing a testable backflow prevention device.
• To ensure correct and safe application of grey water, please consult your local council, the NSW Guidelines and the NSW Department of Energy, Utilities and Sustainability.

Australian Government Initiatives

On 30 January 2009 the Minister for Climate Change and Water announced that the Australian Government is offering rebates of up to $500 to households for:the purchase and installation of a permanent greywater treatment system. For more information click here.

• Department of Water and Energy