Water quality alerts

SA Water routinely monitors the quality of several public water resources for microbiological (eg blue green algae, E. coli, protozoa) and chemical levels and provides results to SA Health. Health advice will be issued when there is a health risk to the public.

Not all water sources in South Australia are tested for water quality.

Avoid contact with fresh water (eg rivers, lakes, creeks, dams) if it has scum or a coloured film on the surface.

Do not drink water unless you know it is safe. Untreated water can cause gastroenteritis including diarrhoea, vomiting and nausea.

Current alerts

Goolwa Channel — 2 May 20025


SA Health advises people to avoid swimming, diving or other activities that might involve accidental ingestion of water from the Goolwa Channel after testing identified elevated levels of potentially harmful blue green algae.


People living in the area or visiting Lake Alexandrina and the Goolwa Channel can still enjoy boating and fishing but are strongly advised to take extra care not to ingest the water in the channel. The affected area stretches from Point Sturt to the Goolwa Barrage where water samples showed elevated levels of the algae.


Unlike other forms of blue green algae, the species detected there generally does not form scums, so is not easily visible to the naked eye. It is the same form of algae that closed Lake Alexandrina to swimming and diving from March to August in 2024.


Direct contact with the water could cause irritation to the skin, eyes, ears, nose and mouth. Swallowing water containing the algae can cause gastrointestinal symptoms including vomiting, diarrhoea and abdominal cramps.


Southern Fleurieu Peninsula, Yorke Peninsula and Kagaroo Island — updated 7 May 2025


There have been reports of a significant bloom of algae affecting the waters around the Southern Fleurieu Peninsula, Yorke Peninsula and Kangaroo Island.


This bloom can travel depending on weather and water conditions.


Exposure to algae, including through breathing in algae particles (or aerosols) can cause skin irritation (if swimming in the water), eye irritation (swimming or exposed to sea spray or aerosols) and respiratory symptoms such as cough and shortness of breath (through exposure through aerosols carried on the wind or sea-spray).


There have been reports of people experiencing symptoms from users of beaches and nearby residents in the area between Victor Harbor to Goolwa. People who have experienced symptoms so far have reported their symptoms going away within several hours of leaving the water or beach.


The alga does not produce a toxin that is harmful to humans or could cause long term effects.


 What to do:


• Avoid swimming in obviously affected areas and avoid contact with discoloured water. If you do enter this water, take care to wash in clean water afterwards.


• Do not eat dead fish and cockles because of decomposition and spoilage. Fish caught live are safe to eat.


• Avoid swimming at beaches where there is discoloured water and foam.


• Avoid walking on affected beaches if experiencing symptoms.


• If you live in the area and experience symptoms outside your home, stay indoors with windows closed, until symptoms resolve.


• If you have symptoms that are severe or do not resolve, seek medical advice from your doctor. Call 000 in a medical emergency.


An update from the Department for Environment and Water is available here.

Monitoring water quality

SA Water routinely monitors water quality from sites along the River Murray as part of ensuring safe drinking water. Results are also used to inform the community about water quality safety for domestic use (laundry, irrigation, bathroom etc) and recreational activities.

See the SA Water – water quality testing locations (PDF 106KB) to see where testing is regularly done.

Testing frequency

  • E. Coli - weekly to monthly, depending on location.
  • Cyanobacteria - weekly.
  • Chemicals - weekly to monthly, depending on location.

Testing other sources

SA Health and SA Water may test other water sources not listed above, and testing frequency will increase if there is a public health concern.

Blue green algae (cyanobacteria)

Blue green algae (cyanobacteria) can build up in fresh water, which can sometimes cause bright coloured surface scums or algae ‘blooms’ to form. Some blue green algae produce toxins which can be harmful to humans and animals.

Blackwater

Blackwater in the River Murray poses no direct public health risk. In a small number of people, blackwater may cause a skin irritation due to sensitivity to natural organic matter in the water.

It is recommended not to drink water from the River Murray at any time unless it is treated.

For more information, see Blackwater on the Department for Environment and Water website.

More information