A scheme to reclaim 4.3billion litres of effluent for industry in western Sydney may not be ``sexy'' said Water Minister Nathan Rees, but it's probably unique.

Mr Rees was announcing last Wednesday that contracts for the $100million Rosehill-Camellia Recycled Water Scheme had been signed with AquaNet Sydney and Veolia Water Australia.

The companies will build and operate a water-treatment plant at Fairfield to recycle sewerage from treatment plants at Fairfield and Liverpool.

An existing network of disused gas pipes will transport the effluent to the treatment plant and then onto companies including Basell Australia, James Hardie, Rosehill Gardens, Visy Paper and Marubeni Australia Power Services.

During a tour of the Visy Paper recycling plant at Smithfield to mark the signing of the contracts, Mr Rees said the project would take Sydney a step closer to recycling 70billion litres of water a year by 2015.

"Provision of both potable water and recycled effluent into the same property is easy in greenfields sites where's it's just a matter of putting pipes in and connecting up to the sources,'' he said.

"But where there's already development, whether commercial residential or industrial, it's a very different story.

"If you want to retro-fit homes to get recycled water into each home, it's about $9000 per property.

"The cost is just exorbitant you can't afford it.

"This is the first time in the world, as far as we can determine, that we've been able to get recycled water systemically into an already established urban area.

"Not only does this make good sense in terms of water policy but it makes good financial sense for the organisations.

"At 1.8megalitres a day you're looking at about $10,000 a week on potable water expenditure, that's $500,000 a year.

"This is stuff that's never been done anywhere else in the world. It's fundamentally re-engineering the way we deliver water and water services.

"We're making serious gains in a way that no other jurisdiction in Australia is making.''