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, including 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 (2011), 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 (2011), 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 and 4 mg/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, with the ideal range in a chloraminated system typically between 0.1 and 0.3 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 (2011), 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.
As a result of our rigorous treatment processes and water quality monitoring programs, your tap water from our drinking water systems 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 (2011), which includes the guideline amount for chloramine in drinking water.
Some people can experience a response to various types of environmental factors and occasionally, this can include skin irritations associated with people showering in both chlorinated and chloraminated water. These instances are uncommon and can be linked with other pre-existing conditions. SA Health recommend that you seek medical advice from your GP with regards to your individual health circumstances and these skin irritations.
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.
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.
Your tap water is safe for humans and animals, except aquatic pets, 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.
The health of the aquatic animals living in your fish tank, aquarium or pond depends on many factors that influence one another. Tap water and the compounds it contains are only some of these factors that need to be managed.
See more information here on the safe use of tap water in your fish tank, aquarium or pond. For advice specific to your own requirements, speak to your local pet shop or aquarium retailer.
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.
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.
Home dialysis units are fitted with a filter that removes both chloramine and chlorine from the water supply.
For more information, contact the Biomedical Engineering Team at the Royal Adelaide Hospital on (08) 7074 5500.
Whether you’re topping up your pool or filling it for the first time with chloraminated tap water, you may need to add more chlorine than normal to achieve the right chlorine concentration. 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 sahealth.gov.au for information on home swimming pool maintenance.
