Sydney toilets and laundries to use recycled stormwater

Green Square Water, a private water utility owned by Flow Systems, will use recycled stormwater at 20 sites to service 7000 residents and 8500 workers in Sydney’s Green Square neighbourhood.

As part of an agreement with the City of Sydney, Green Square Water will design, build and maintain the recycled water network using a parallel plumbing system installed in the new buildings, providing up to 900 kL of recycled water every day.

Flow Systems will treat the stormwater using three processes: ultrafiltration, reverse osmosis and purification. Managing director and founder Terry Leckie said the water is purified to high standards, with the Independent Pricing & Regulatory Tribunal and NSW Health monitoring the network to ensure it meets health and safety requirements.

To be used in toilets and laundries, the recycled water will be cheaper than Sydney Water’s drinking-quality water, resulting in an average $20 drop in annual water bills. This will make a big difference to apartment dwellers, who are known as the highest consumers of drinking water but one third of what they use is either flushed down the toilet or used in the laundry.

Lord Mayor Clover Moore said the City of Sydney is “already bringing storm and rainwater harvesting and re-use programs to many of our parks and public buildings”, but this is the first time it has been available for businesses and residents - “and in a way that benefits the environment and is commercially viable”.

Moore expects Sydneysiders to be consuming 20 billion litres of stormwater per year by 2030.

Leckie explained that the project allows us “to harness stormwater, purify it on site and re-use it to green gardens and sporting fields, plus [for] air cooling, clothes washing and toilet flushing”. The recycled water is planned to be used to irrigate Matron Ruby Park on the old grounds of South Sydney Hospital and the planned library at Green Square.

The project is the first of many being formulated under the City of Sydney’s Decentralised Water Master Plan and is being partially funded through the City and the Australian Government’s National Urban Water and Desalination Plan, part of the Water for the Future initiative.