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Recycled water (Werribee)

For information on Shandy Mix salinity levels visit Waterline. 

  • 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 Energy, Environment and Climate Action, 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 water under the scheme in January 2005.

  • Class A recycled Water

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

    Class A recycled water is water that has been collected from the sewage catchment and treated to make it safe for a wide variety of non-drinking uses.

    The process used to ensure the Class A recycled water is safe for its intended use is strictly regulated by the Environment Protection Authority (EPA) Victoria.

    The treatment process consists of multiple stages of treatment that remove different types of compounds. At the Western Treatment Plant (WTP) we use three stages of treatment, primary, secondary and tertiary:

    • Primary treatment involves physical removal of large pollutants such as plastics, rags and other material that will sink or float.
    • Secondary treatment involves biological removal of compounds like ammonia, nitrogen, carbon and other dissolved compounds.
    • Tertiary treatment involves disinfection to kill residual pathogens left in the water, such as bacteria, protozoa and viruses.

    It is important to remember that although Class A recycled water has been treated for reuse, it should only be used for its intended purpose. For more information on recycled water, visit Melbourne Water.

  • Uses of Class A recycled water

    Class A recycled water can be used for a wide range of non-drinking purposes including for the irrigation of food crops intended for raw or unprocessed consumption. 

    It should not be used for drinking, cooking, showering, filling domestic swimming pools or drinking water for pigs. 

    Class A recycled water is supplied by Melbourne Water who follow strict state and national guidelines for producing recycled water. 

    Please add another accordion titled: Class A recycled water and blue-green algae

    The Victorian blue-green algae circular, published by the Department of Energy, Environment and Climate Action (DEECA), includes guidance on the limits (cells/mL) beyond which blue-green algae is considered a public health risk.

    Melbourne Water follows the recommendations set by DEECA and will cease supply of Class A recycled water if the blue-green algae cell count exceeds the limit published in this guide for swimming. A notification is sent to Southern Rural Water customers when the cell count reaches 10% of the limit to remind customers to limit their exposure to the water.

    More information about blue-green algae can be found on our blue-green algae warning page.

 

Using Class A recycled water for irrigation

Western treatment plant recycled water quality

Click the links below to access the “western treatment plant recycled water quality – Post disinfection” report for the corresponding month.