The Cessnock Wastewater Treatment Works (WWTW) serves the communities of Cessnock, Aberdare, Bellbird and Nulkaba.

It currently treats 5.8 megalitres per day and can handle wastewater from a population equivalent to 32,000 people.

Treatment Process

The Cessnock WWTW is designed to remove nutrients (nitrogen & phosphorus) and to provide a high level of disinfection.

It provides tertiary treatment of the wastewater by the following process:

  • inlet works, including screening flow meter and grit removal
  • soil bed biofilter for odour control
  • two primary clarifiers
  • four trickling filters
  • a humus clarifier
  • chemical dosing to remove phosphorus
  • anaerobic digestion system for sludge stabilization
  • an onsite Centrifuge dewatering system
  • a tertiary flotation plant to remove algal cells and other suspended solids
  • a UV disinfection system after flotation.

Recycling & Reuse

All biosolids produced at the Cessnock Wastewater Treatment Works (WWTW) are beneficially used for mine site rehabilitation.

Recycled water is used for:

  • grit and screening washing
  • general wash down around the WWTW
  • ground irrigation.

A nearby farmer and golf course also take up to 50 megalitres per year of recycled water from the Cessnock WWTW for irrigation. 

The rest of the effluent is discharged to Black Creek. Downstream irrigators are also licensed to extract water from Black Creek, the flows of which are mainly sustained by treated effluent from Cessnock WWTW.

Hunter Water recycles approximately 5091 megalitres per year. Learn more about our recycling and reuse initiatives.