Water Recycling at Rouse Hill


A new residential development at Rouse Hill, Sydney is being supplied with treated wastewater, which households can use for non-drinking purposes.

Sewage from houses goes to a nearby treatment plant. The treated water returns via its own pipe system.

The treated water is not for drinking. It can be used for toilet flushing, irrigating gardens, and washing cars. Taps and pipes are lilac to distinguish them from the drinkable water plumbing. The taps have a removable handle and a reverse thread hose fitting.

On some days the treated is water is topped up with drinking water. Presumably in hot or dry periods, when outdoor water use exceeds treated water supply. On average 15% of the treated water supply comes from drinkable water.

Treated water at Rouse Hill has a cheaper per-unit price than drinkable water and is not subject to the same dought restrictions. So lawns in households with access to treated water tend to be greener than drinkable water only lawns.


Water Recycling - Rouse Hill

Rouse Hill Recycled Water Area Project. Sydney Water

In Sydney's north-west, recycled water has being introduced to new properties in the Rouse Hill Development Area.

These homes have two water supplies: recycled water and drinking water. This is known as dual reticulation. The recycled water taps, pipe-work and plumbing fittings are coloured lilac to ensure that recycled water is not confused with drinking water.

Recycled water is highly treated wastewater. Recycled water goes through a complex series of treatments including micro filtration and chlorination in addition to the usual high level of treatment it receives. Recycled water has strict guidelines that limit its use to toilet flushing and outdoor purposes such as car washing and gardening. It is NOT for drinking.

Recycled Water Plumbing - Rouse Hill

Recycled Water Plumbing. Sydney Water

Houses in the Rouse Hill Recycled Water area, using recycled water, require a dual-plumbing arrangement.

The NSW Recycled Water Guidelines state that special recycled water taps must be used on the recycled water system. These taps are lilac coloured, have a removable handle and a reverse thread hose fitting.

Rouse Hill Avoids Drought

Turf War as Streets Green with Envy. Vanessa McCausland and Lillian Saleh. Daily Telegraph. 2004.6.17

Most of the lawns in Rouse Hill are thriving - thanks to the suburb's connection to a recycling water plant. Sewerage water is treated and recycled back into lilac-coloured pipes which residents can then use to water their gardens and flush their toilets.

Baby William O'Neill is among the new generation of residents in Rouse Hill who is never likely to see the ugly brown grass of drought.His parents Nathan and Melinda O'Neill said they couldn't remember the last time they watered their lush-green lawn - instead, they use fertiliser and mow it twice a week.

Sydney Water said yesterday it was looking at introducing recycled water pipes in new developments. "It is fairly difficult to retrofit existing suburbs with recycled water because it means digging up pipes. But we are looking to do more of this in the future where there is an opportunity at the planning and development stage."

Rouse Hill Water - Recycled or Fresh?

Recycled Water is being Topped Up with Fresh to Meet Demand. Nick O'Malley. Sydney Morning Herald. 2003.12.9

Thousands of Sydney residents are wasting millions of litres of potable water in their gardens under the mistaken belief it is recycled.

The 13,000 households buy recycled water from Sydney Water's Rouse Hill plant, but when demand for the "grey" water - which is not subject to restrictions - outstrips supply due to hot weather or plant failures, Sydney Water tops up the supply with fresh drinking water.

On an average year, 15 per cent of the water sold as recycled by the Rouse Hill plant is clean drinking water.

A decision was made not to tell customers that on some days they were using clean rather than recycled water because it might confuse them.

Of 438 million litres of potable water sold as recycled between September 2001 and August 2002, more than half (57 per cent) was due to plant failure.

The top-ups appear to have cost Sydney Water $200,000 a year. Residents pay a little over 30 cents for a thousand litres for the grey water, about one third the cost of potable water.

Recycled Water - Pricing

Recycled Water Pricing. Sydney Water

Recycled water is about one third of the price of drinking water. Plumbing a house for recycled water is more expensive than for a normal house. There is a recycled water service charge and a recycled water usage charge.