TREATED sewage will be used to irrigate crops, golf courses, and a racecourse in Melbourne's outer south east under a water recycling scheme.

The $25-million Eastern Irrigation Scheme, one of Victoria's largest class A water recycling schemes, will deliver about 5000 million litres of water a year to the Cranbourne-Five Ways.

Class A water is the highest quality of recycled water, which has undergone a three stage treatment process and pathogen removal.

A dual pipe system in residential developments will also allow the recycled water to be used for flushing toilets and watering gardens.

The sewage is initially processed by Melbourne Water at the Eastern Treatment Plant in Carrum Downs.

Private company TopAq further treats about 3.5 per cent of the plant's recycled water at their ultra filtration plant, then delivers it through 50km of pipes in a 170sq m area around Cranbourne.

The scheme's first customer was the Sandhurst Club residential development in Carrum Downs, which will use 1200 million litres of recycled water a year on two golf courses, gardens and toilet flushing in 1850 homes.

Water Minister John Thwaites, who launched the scheme from the Eastern Treatment Plant today, said the project was an important step in the State Government's target to recycle 20 per cent of Melbourne's wastewater by 2010.

About 70 vegetable growers in the Werribee region have already signed up for 4100 million litres from a key water recycling scheme in Melbourne's west.

Source: AAP