Skip to main content


Biosolids are a nutrient rich organic material that is produced from the wastewater recycling process.

With a combination of water and organic materials, biosolids contain valuable nutrients such as nitrogen and phosphorous. They make a viable alternative fertiliser solution if applied under the right conditions.

Biosolids have a soil-like consistency and are used as:

  • fertilisers
  • soil conditioners
  • topsoil substitute for landfill
  • compost with green waste
  • structural material in the construction of roads.

Biosolids meet specific quality criteria and are regulated by the Environment Protection Authority (EPA).

Greater Western Water is partnering with local farmers and communities to develop a sustainable biosolids industry. If you are interested in using biosolids for agricultural purposes please download, complete and return an Expression of Interest form. If you have any questions, please contact us on 13 44 99.

Biosolids to Biochar Project

Our Melton Recycled Water Plant (RWP) is piloting innovative technology on site to convert biosolids to biochar, a material with a variety of uses for farmers and the wider agricultural industry.

Although significant progress has been made to increase reuse and reduce waste from our wastewater treatment processes, some waste – in the form of biosolids is currently being stored or sent to landfills.

The biosolids to biochar project aims to eliminate waste from our wastewater treatment processes entirely by using innovative technology to convert excess biosolids to the value-added product, biochar.

PYROCO, developed by RMIT’s research team in collaboration with Greater Western Water, South East Water and Intelligent Water Networks, is the name for the energy-neutral process used to convert biosolids into biochar.

Piloting this process at Melton RWP will provide essential information to help understand how it could be used on a larger scale across the water industry.

    Further information

    More Information