Disinfecting your drinking water

Disinfecting your drinking water

All drinking water needs to be disinfected to make it safe to drink. We filter and use a range of treatment methods, from the moment it starts its journey to your property from one of many sources.

Like chlorine, chloramine is a disinfectant that destroys bacteria and other pathogens that can be present in source water and ensures your tap water is clean and safe to drink.

In South Australia, drinking water has been safely and effectively disinfected with chloramine since the 1980s. More than  220,000 South Australians have been supplied with chloraminated tap water for many years, being provided across the mid north of the state, Port Pirie, Port Augusta, Whyalla, the Yorke Peninsula and in the southern Adelaide Hills and Tailem Bend, Strathalbyn and Keith.  Chloramination is also used  in Sydney, Brisbane, Bendigo and a large part of Western Australia as well as in international water supplies.

Across Australia, drinking water is governed by health regulators that enforce the Australian Drinking Water Guidelines, which are among the most stringent in the world. In South Australia, our robust Drinking Water Quality Management System enables us to consistently meet or exceed national drinking water quality targets. We maintain these high standards through SA Health-approved drinking water quality monitoring programs, where we carry our more than 370,000 water tests in our laboratories each year. If we were working around the clock, we’d carry out more than 1000 tests per day, or one test every 100 seconds.

SA Health, through the Australian Drinking Water Guidelines, and the World Health Organisation both confirm that chloramine is safe and effective in drinking water supplies.

To see a full profile of the drinking water supplied to your area, including how it is disinfected, you can search your postcode and suburb in our handy search tool.

About chloramine

Chloramine is made by combining ammonia and chlorine. We only use a small amount of chloramine, typically between 2 to 4mg/L, to ensure a safe but effective disinfection residual in the drinking water supplied to our customers. The amounts of free ammonia in drinking water as a result of chloramination are also very small, typically less than 0.2 mg/L. We constantly monitor these levels as part of our water quality monitoring program to ensure your drinking water is safe, clean and in reliable supply. As outlined by the Australian Drinking Water Guidelines, only at levels of greater than 1000 mg/L (that’s about 5,000 times higher than concentrations in drinking water) does ammonia have a potential effect on human health.  As these concentrations are highly unlikely to occur in drinking water, no health-based guideline for ammonia has been set.

Why water utilities disinfect drinking water with chloramine

Like chlorine, chloramine destroys bacteria and other pathogens that can be present in source water. Chloramine is also used as a disinfection method because it persists in the water supply for a long time which is useful for long pipe networks such as those used in South Australia’s Fleurieu Peninsula network which has about 600 kilometres of water mains.

Know the facts

There’s a lot of misinformation about chloramine online so we want to make sure you have the facts, including about the safety of your drinking water. We recommend you rely on expert health-based advice for information.

Drinking or bathing in chloraminated water will not make you sick

As a result of our rigorous treatment processes and water quality monitoring programs, your tap water is safe to drink, cook with and bathe in, regardless of its disinfection method.

Only very small amounts of chloramine are used in drinking water disinfection and our chloraminated drinking water meets all requirements of the Australian Drinking Water Guidelines, which includes the guideline amount for chloramine in drinking water.

Some people can experience a response to various types of environmental factors and occasionally, SA Health have received reports about skin irritations associated with people showering in both chlorinated and chloraminated water. These instances are rare and often linked with other pre-existing conditions.

If you have a question about your individual health circumstances and your tap water, we encourage you to speak with your GP or contact SA Health’s expert water quality team directly on 08 8226 7100 or waterquality@sa.gov.au

Chloramine in drinking water doesn’t have a major affect on taste and smell

We understand people have different perceptions about the taste of water and personal preferences vary.

Some people notice that tap water disinfected by chlorine can have a distinct smell and taste. Disinfecting with chloramine lessens this effect, and it’s acknowledged as a better tasting water through independent and blind taste tests. Chloraminated drinking water produced by the Morgan Water Treatment Plant has also won the prize for best tasting drinking water in South Australia on several occasions in recent years.

Chloramination is not a lesser quality, or cheaper way to disinfect drinking water supplies

While the cost of water treatment technologies is considered, it is of far less importance than ensuring the safety of drinking water that consistently and holistically achieves the compliance and intent of the Australian Drinking Water Guidelines.

Before the disinfection process which destroys pathogens (bacteria, virus and protozoa), our water supplies also undergo filtration. Filtration methods used by SA Water can include granular activated carbon, membranes and sand filtration, depending on the source of the water

Dogs and cats and other pets can drink chloraminated drinking water

Your tap water is safe for humans and animals to drink. In chloraminated supplies, only small amounts of chloramine are used and they are in line with the guideline amount set in the Australian Drinking Water Guidelines to ensure drinking water is safe and free from naturally occurring pathogens.

Fish and other aquatic pets are impacted by drinking water

Fish are sensitive to both chlorine and chloramine and any drinking water supply must be neutralised before it is used to fill fish tanks, aquariums and ponds. Retailers selling fish and aquariums are aware of this and sell water conditioners to neutralise the residual chorine and chloramine in tap water. Talk to your pet shop for advice.

Chloramine in drinking water is not uncommon, and is not banned in other countries

Chloramine is a common water disinfection method across the world. It’s been used effectively in South Australia since the 1980s with more than 220,000 customers across our state drinking chloraminated water. It is used in all mainland states of Australia , including major cities like Sydney and Brisbane, and in a wide range of international drinking water supplies such as London and Singapore and across the United States.

Chloraminated water is less corrosive to pipes

Chloramine disinfection enables us to raise the pH of your drinking water so that it is less corrosive to pipes and water mains than chlorinated water.

Most pipes are wrapped in cement to give them strength. Acids, which are liquids with a pH under 7, dissolve cement. This causes corrosion to the pipe surface. Acids are also highly corrosive to cast iron, which most pipe valves are made of.

Most water has a pH of between 7 and 7.5. When drinking water is disinfected with chlorine or chloramine, additives are used to ensure the pH doesn’t drop below 7. However, chlorine must stay below a pH of 8 to be effective, while chloramine remains effective at pH levels up to 9.5.

This enables us to keep your chloraminated drinking water at a pH of approximately 8, which is the same pH as seawater. The slightly higher pH has no effect on the taste or quality of your water, but it is less likely to corrode pipes and valves. This extends the lifespan of our water mains and network which can mean fewer temporary interruptions to your drinking water supply.

Changing to chloramine in the Fleurieu Peninsula

In early December 2021, the disinfection method for the Fleurieu Peninsula’s mains drinking water supply will change from chlorine to chloramine to improve the quality of tap water.

This will apply to homes and businesses in and surrounding Victor Harbor and Encounter Bay through to Middleton, Goolwa and Hindmarsh Island as well as Willunga, Sellicks Beach and parts of Aldinga Beach.  People in Myponga Township changed to chloraminated tap water in 2018, followed by Yankalilla, Normanville and Carrickalinga in March this year.

In the Myponga Reservoir which supplies drinking water across the Fleurieu, a large amount of leaves, earth and sediment runs into the catchment which produces dissolved organic carbon.

Chlorine can react with this and produce disinfection by-products – one of which is trihalomethanes (THMs). Levels of THMs in some parts of the Fleurieu Peninsula’s drinking water network have exceeded recommended guidelines from time to time, and while SA Health has always confirmed the water is safe to drink, we aim to achieve the guidelines 100 per cent of the time. Changing from chlorine to chloramine will ensure THMs are continuously within the recommended guidelines.

To stay informed about the change to chloraminated tap water in the Fleurieu Peninsula, register to receive updates at watertalks.sawater.com.au.

What to expect during the change

As the tap water changes from early December 2021, if you live or work in the Fleurieu Peninsula you may notice a temporary change in the taste and smell of your drinking water. This is normal and an expected part of the transition period. It may take about two to three weeks to settle. The smell will be more distinctive at first, and then lessen as the water moves through the pipes.

As the chloraminated water begins to travel through the network, it may lift organic matter that has built up on the inside of pipes over time, called biofilm. This is not harmful, but it can temporarily discolour the water. The water is still safe to use. If you experience discoloured water, simply run a sink tap or give your garden a drink to help it pass through the system, until the water runs clear.

Fish and aquatic pets

Whether chlorinated or chloraminated,    tap water must be neutralised before it is used in fish tanks, aquariums and ponds to protect your fish or other living aquatic creatures. This can be done using a product such as a water conditioner or a carbon filter. If you’d like specific advice on the most appropriate product for your situation, please contact your local pet shop or aquarium retailer.

While very small amounts of ammonia can sometimes be present naturally in fish tanks, the higher levels of ammonia through the use of chloramine to disinfect drinking water can be harmful to fish and aquatic amphibians, even at low levels.

If you have a fish tank or pond, any change from chlorinated to chloraminated water could affect your fish or other living aquatic creatures.

Home dialysis patients

We are working closely with SA Health, and the Biomedical Engineering Team at the Royal Adelaide Hospital (RAH) is aware of the upcoming changeover to a chloraminated water supply. Home dialysis units are fitted with a filter that removes chloramine from the water supply.

If you, or anyone you know in the changeover area has or will be receiving a home dialysis machine, it is important that you contact us or the RAH so we can work with you. Please contact Amy Czura from SA Water on 1300 SA WATER or project@sawater.com.au or Biomedical Engineering at the RAH on (08) 7074 5500.

Pools and spas

After the changeover, you may need to add more chlorine than normal to achieve the right chlorine concentration, whether you’re topping up your pool or filling it for the first time with chloraminated tap water. Make sure you continue to test your overall chlorine concentration as part of your normal maintenance routine. We suggest you contact your pool supplier for specialist advice, or refer to SA Health’s information about swimming pools and chloraminated water at sahealth.gov.au.

We’re here to help

If you have questions, please call us on 1300 SA WATER or email project@sawater.com.au

If you have questions about health-related matters according to your specific circumstances, the Australian Drinking Water Guidelines or the Safe Drinking Water Act (2011), you can contact SA Health’s specialist Water Quality Unit on 08 8226 7100 or waterquality@health.sa.gov.au.