Chlorine and chloramine in drinking water

Most of South Australia’s drinking water is disinfected with either chlorine or chloramine to destroy bacteria and other pathogens that can be present in source water, ensuring water supplied to homes and businesses is safe and clean to drink.

Compared to chlorine, chloramine persists in the water supply for a long time, making it suitable for lengthy pipeline networks, primarily in regional areas of the state. Chloramine provides added protection against network recontamination or growth of some naturally occurring pathogens.

Chloramination was originally introduced to South Australian drinking water supplies in the 1980s to control the growth of the potentially fatal organism N.fowleri, which was endemic in a number of supplies. The introduction of chloramine virtually eradicated the organism. Chloramination has also been shown to be effective against other organisms such as Legionella, which commonly grow in building plumbing systems.

Chloramine is commonly used to safely disinfect water supplies across Australia and overseas. SA Health, through the Australian Drinking Water Guidelines (2011), and the World Health Organisation (WHO), both confirm that chloramine is safe and effective for this use.

Why we disinfect drinking water

Drinking water supplied to premises throughout South Australia must comply with the Australian Drinking Water Guidelines (2011) and the WHO Guidelines for Drinking Water Quality. To ensure that it meets those guidelines and is clean and safe to drink, it must be disinfected.

How water is disinfected

Chlorine or chloramine is added to drinking water at South Australia’s treatment plants, before it’s supplied to customers, in accordance with the Australian Drinking Water Guidelines (2011).

Safeguards to ensure over-dosing does not occur

Concentrations of chloramine and chlorine in the water are constantly monitored by SA Water or the relevant drinking water supplier, to make sure they’re at the optimal level of maximum effectiveness while complying with the Australian Drinking Water Guidelines (2011).

There are several controls that help ensure the correct amount of chlorine or chloramine is added. Regular water sampling and monitoring are undertaken at both the treatment plant and within the connecting pipeline network for all drinking systems across South Australia.

Human reactions to chlorine and chloramine

Chloraminated and chlorinated water are safe for humans and animals, with only very small amounts used in water disinfection, in line with the Australian Drinking Water Guidelines (2011).

A small number of people may experience skin irritation from chlorinated or chloraminated water.

If you are concerned, you should always seek medical advice from your GP or healthcare provider.