New analysis has estimated South Australia’s ongoing algal bloom has cost the state more than $250 million, as environmental groups call for major gas producers to help fund the recovery.
The bloom was first reported in March 2025 at Waitpinga Beach on the Fleurieu Peninsula, when surfers and beachgoers reported irritation and illness in the water. Dead marine life and thick foam soon appeared along parts of the coast as the bloom spread.
Analysis released today by Conservation Council South Australia, compiled by Springmount Advisory, estimates the economic impact has exceeded a quarter of a billion dollars over the past 12 months.
The report suggests more than $46.8 million has been lost from tourism, more than $100 million from the fisheries industry and more than $100 million through government response costs.
Conservation Council SA chief executive Kirsty Bevan said the scale of the financial impact highlighted the need for stronger action.
“It’s only fair that South Australia’s biggest climate polluters contribute to repairing the damage they cause,” Kirsty Bevan said.
“Given the scale of the gas industry’s emissions, it should be footing the bill for climate damage like this algal bloom.”
The organisation argues a levy on oil and gas production in South Australia could raise between $254 million and $275 million a year to help cover environmental damage and restoration.
The algal bloom has persisted along large stretches of the state’s coastline for much of the past year, killing marine life and affecting fishing, tourism and coastal businesses.
Separate scientific research released last week has also shed new light on the bloom’s origins.
Researchers analysing archived seawater samples found the toxic algae species Karenia cristata – now considered a dominant species in the bloom – has been present in South Australian waters for at least a decade.
Scientists believe the species dramatically increased in abundance in 2025, though the exact cause is still being investigated.
Preliminary government research has pointed to a combination of environmental factors leading up to the event, including increased nutrient loads from River Murray floods, a lack of cold-water upwelling and a marine heatwave.
The bloom continues to be studied by researchers from the University of Technology Sydney, the South Australian Research and Development Institute, CSIRO and the Integrated Marine Observing System.
