Sewage treatment

Wastewater from homes and businesses is conveyed to a wastewater treatment plant through a series of pipes and pump stations.

We then treat the wastewater before it is reused or discharged to rivers in accordance with the high standards determined by the Environment Protection Authority.

Central Highlands Water has ten wastewater treatment plants. They are located in:

  • Avoca 
  • Ballan
  • Ballarat South
  • Ballarat North (Including Creswick)
  • Beaufort
  • Cardigan Village
  • Clunes
  • Daylesford (Including Hepburn)
  • Maryborough
  • Skipton

The treatment process at each treatment plant depends on the type of sewage being treated and also on how the treatment effluent will be used. The treatment steps across our wastewater plants are:

Pre-treatment – This mechanical process is used to remove foreign objects from the sewage such as rags and grit.

Primary treatment – This process step involves hydraulically slowing down the sewage to allow the solids to settle out and fats and grease to be skimmed off the top.

Secondary treatment – This step involves biologically removing small contaminants in the sewage through the use of bacteria. Tanks known as clarifiers are then used to help remove the bacteria from the clear liquid. At some treatment plants, chemical addition is required to help remove some nutrients.

Tertiary treatment – This step involves disinfecting the clear liquid to kill off any harmful organisms. We then use ultra violet light to carry out this process.

Once the sewage has been treated, clear effluent is then reused on land or discharged to waterways.