Why and how water is treated
The way water is treated depends on its source. South Australia has more than 80 different water supply systems.
We use the best treatment methods based on what’s required, providing the highest quality of drinking water to everyone in the state.
Our standards for your water
We treat your water to make sure it looks, smells and tastes right—and meets health standards. The treatment method we use depends on the water source and is chosen for its effectiveness in meeting our high standards. To learn how your tap water is disinfected, use our location-based search tool.
Learn about your suburb’s drinking water
Water treatment glossary
Chlorine is used in the water treatment process to protect public health and ensure water is safe to drink, destroying bacteria and other pathogens that can be present in source water.
Chloramine is used to safely disinfect water in Australia and overseas. It is approved as safe and effective by SA Health, the Australian Drinking Water Guidelines, and the World Health Organisation.
Like chlorine, chloramine kills bacteria and other pathogens, keeping tap water safe. It’s more effective in long pipes, so we use it in extended water systems across South Australia.
Chloraminated water also tastes better. It performs well in taste tests and is a favourite in blind trials. In one study using water from Myponga Reservoir, people preferred the taste of chloraminated water over chlorinated water.
Chloraminated water must be neutralised before use in fish tanks, aquariums or ponds to protect aquatic life. Use a water conditioner or carbon filter. For advice, speak with a vet or pet shop.
Although small amounts of ammonia can occur naturally in tanks, higher levels from chloramine can harm fish and amphibians, even in low doses
Learn more about chloramine and its use in drinking water in South Australia.
Our desalination plants use a technology called reverse osmosis which removes up to 99 per cent of the impurities and salt in the water. Once the impurities are removed, the water is treated to meet the Australian Drinking Water Guidelines, ensuring it is safe and ready to drink.
Saline concentrate is one of the by-products of the desalination process and at the Adelaide Desalination Plant at Lonsdale, this concentrate is put back into the ocean using a series of special diffusers. These sit about one kilometre off-shore and rapidly mix the concentrate with seawater to dilute it.
Fluoride is a trace mineral found naturally in water, soils and foods. It is added to South Australia’s metropolitan and major country drinking water supplies, as mandated by our state health authority, because it's proven to provide a significant public health benefit. Fluoride does not affect taste, look or the smell of your drinking water.
For more information on fluoride in water, visit the SA Health website.
You can find the full glossary of what makes up your water here
Other treatment options
We’ve invested in membrane filtration plants as part of our commitment to the future of water treatment. This process filters water through fine membrane pores, creating a stronger barrier against certain pathogens and further reducing public health risks.
Many South Australian groundwater sources have higher levels of iron and other chemicals. The iron removal process takes these natural elements out of the water. Iron is not a health risk, and the water is safe to drink, but high levels can affect its colour and taste.
We’re upgrading our iron removal plants to reuse backwash water. This reduces groundwater use and lessens environmental impact.
Our Mount Pleasant and Middle River Water Filtration Plants were the first plants in the world to use Magnetic Ion Exchange (MIEX®) to treat the water.
Discovered through years of research by SA Water, Orica and CSIRO, MIEX removes dissolved organic carbon—the main cause of water colour. It also improves taste, smell and reduces the levels of chlorine needed.
Some plants use ultraviolet (UV) light to destroy bacteria, viruses and protozoa, making them safe for humans. The UV dose depends on water clarity, dissolved compounds and microorganisms.