Tanilba Bay Wastewater Treatment Works

The Tanilba Bay Wastewater Treatment Works serves the communities of Lemon Tree Passage, Mallabula and Tanilba Bay.

It currently treats 1.3 megalitres per day and can handle wastewater from a population of up to 10,000 people.


The Tanilba Bay Wastewater Treatment Works provides secondary treatment of wastewater through the following process:

  1. screening of solids;
  2. extended aeration through intermittently decanting aeration tanks for nutrient removal (nitrogen only);
  3. UV disinfection of treated effluent;
  4. aerobic digestion and lagooning of biosolids for later dewatering and reuse in mine site rehabilitation projects.

Recycling and reuse

All biosolids produced at the plant are beneficially used for mine site rehabilitation and pasture improvement projects.

Effluent from the treatment works is returned to the environment through four sand infiltration ponds located along its eastern boundary. Flows are currently directed to Ponds 1, 2 & 3, which are operated in dry/wet mode and Pond 4 which is retained for wet weather flows.

At Hunter Water, we recycle approximately 5,000 megalitres of effluent per year. Learn more about our recycling and reuse initiatives..

Environmental Licence Monitoring

Pollution monitoring data is collected by Hunter Water, as required under the Environment Protection Licences (EPL) issued by the NSW Environment Protection Authority (EPA).