IN a first for NSW, carbonisation technology will soon be used as a new and innovative way to treat byproducts of wastewater treatment, within the expanding North West Growth Area.


A $50M upgrade at Riverstone Water Resource Recovery Facility (WRRF) will see biosolids, a wastewater treatment byproduct, collected from an upgraded plant and converted into a sustainable product called biochar. The carbon-rich material can be reused in various applications such as agriculture and manufacturing.

Sydney Water Head of Major Project Delivery Bernard Clancy said the process will not only substantially increase treatment capacity in the region but will also improve the quality of discharge that flows into the Hawkesbury-Nepean River system.

“Biochar is an organic charcoal-like product. The process involves thermally treating the organic and inorganic solid material captured in the process of treating wastewater to remove contaminants such as microplastics, then releasing a clean product back into the environment,” Mr Clancy said.

“It can also enrich soil quality and stimulate crop growth, which helps contribute to more sustainable farming practices and a circular economy model.”

The treatment process to produce biochar is already occurring in Australia. The site in Logan City, Queensland, has been recognised with an international innovation award.

Sydney Water’s carbonisation initiative is part of a series of staged works to expand wastewater treatment capacity in the Sydney’s North West. More than $1.5B will be invested between now and 2030 in the three WRRFs (Riverstone, Rouse Hill and Castle Hill) that service the area.

“The population in this area is expected to double by 2036, which is why we are investing in major upgrades to provide effective wastewater treatment capability and capacity to cater for the forecast growth and to keep local waterways healthy,” Mr Clancy said.

“The planned increase in treatment capacity across the North West Hub will support the servicing of 200,000 new homes by 2056.”

Sydney Water’s infrastructure project pipeline is supporting the NSW Government’s housing growth ambitions with an improved and expanded network across Sydney.

To learn more, visit Sydney Water’s major projects pipeline.

IMAGE: Riverstone Water Resource Recovery Facility (WRRF).