Chlorination is a form of disinfection, which is needed to kill harmful disease-causing germs (called pathogens) that can be present in water from the rivers and dams.


A chlorine particle’s job is to find and kill any bugs. Chlorine gas is injected into the water to kill off bacteria and viruses. Chlorine scatters and breaks up leaving water free of both bacteria and bad tastes.

Micro-organisms like bacteria, viruses and parasites that are too small to filter out, can be killed in a number of other ways including:

  • Heat – by boiling water for a few minutes
  • Chemicals – these can be added to water in tiny amounts that will kill germs but be perfectly safe for us. The most common form is Chlorination (which is used in the Shoalhaven) and one of the chemicals that is used is Hypochlorite.
  • Ozone – ozone gas can be bubbled through the water to kill germs
  • Ultra-violet light – using strong UV lamps or sunlight radiation