SA Health has advised people to avoid 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 avoid swimming and diving and take extra care not to ingest 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. 

It is not related to the ongoing marine 𝘒𝘢𝘳𝘦𝘯𝘪𝘢 𝘮𝘪𝘬𝘪𝘮𝘰𝘵𝘰𝘪 microalgae bloom currently affecting beaches on the Fleurieu Peninsula, Yorke Peninsula and Kangaroo Island.

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. 

SA Health Principal Water Quality Adviser Dr David Cunliffe says it’s fine to visit the area and enjoy its recreational options but not to swim or dive in the channel or drink the water, and keep pets and children well clear. 

“If you have been in the water in this section of the Goolwa Channel and start to feel unwell you should see your GP and tell them you might have been exposed to blue green algae. 

“Dogs are also vulnerable and should be kept out of the water because the algae can stick to their fur and be ingested if they groom themselves. 

“Fish caught in the channel should be cleaned with fresh water and gutted thoroughly before being eaten. SA Water does not source water from the channel. “