Recycled water (Werribee)

6.25ec

Salinity Levels Shandy Mix

ec = electrical conductivity
21 July 2017

Introduction of the Recycled Water Scheme

The Werribee Irrigation District is an important vegetable growing area on the western fringe of metropolitan Melbourne. Using water from the Werribee River, the aquifer below and the recycled water scheme, over 400 growers produce lettuces, broccoli, cabbages and many other vegetables for local consumption and export.

During 1994 the then Victorian Minister for Water, John Thwaites, announced the Werribee Irrigation District Recycled Water Scheme would be established. The scheme was designed to assist in overcoming water shortages due to drought and to secure water for greater production in the future.

During 2004 grower representatives, project partners (Department of Environment, Land, Water and Planning, Melbourne Water and Southern Rural Water), and regulators (EPA Victoria and Department of Health) took up the challenge of bringing the scheme to fruition.

More than $20 million was invested in additional water treatment at Melbourne Water’s Western Treatment Plant, a connecting pipeline into the Werribee Irrigation District, environmental investigations and approvals, and the operating arrangements for the scheme. Growers received the first deliveries of Class A recycled waterunder the scheme in January 2005.

Class A Recycled Water

The Class A recycled water supplied by Melbourne Water is delivered to participating growers by Southern Rural Water through its existing irrigation channels and pipelines.

The recycled water is treated through the standard wastewater treatment system and two additional disinfection systems – chlorination and ultra violet light. The Department of Health has classified the Class A recycled water as safe for irrigation of food crops – including those eaten raw. Victorian standards for Class A Recycled Water comply with strict national guidelines set by the National Health and Medical Research Council.

They are also consistent with standards in the United States, and exceed the international standards for the use of recycled water set by the World Health Organisation. The Department of Health requires an extensive verification process to ensure Class A quality can be guaranteed, and has endorsed Melbourne Water’s recycled water as Class A. EPA Victoria has approved the Environment Improvement Plan for the scheme, which ensures good environmental practice under the Scheme.

Melbourne Water is working to reduce the salinity of the recycled water, which at present needs to be mixed with water from the Werribee River to meet the requirements of the Environment Improvement Plan.