WATER TREATMENT: DISINFECTION
All water supplies should be disinfected in order to protect public health. Disinfection inactivates any remaining bacteria in the water after previous treatment steps and provides a residual disinfectant to inactivate bacteria introduced by any subsequent ingress of contaminated water during storage or distribution.
At present, the principal disinfectant used worldwide is chlorine, although alternatives are being increasingly investigated and process such as ozonation are becoming more important in industrialized countries. It is important to note that all disinfectants produce by-products and that
the greater knowledge about the by-products formed from the use of chlorine because it is this most widely used disinfectant should not compromise it's use. It is also important that
disinfection of water supplies is never compromised because of a risk of potential health effects from by-products in the final water. Any health impacts from chemical contamination is likely to be long-term, whereas the absence of disinfection puts the consumers at risk from infectious diarrhoeal disease.