New Report Explains What Caused South Australia's Algal Bloom Crisis

The report was written by Madina Jaffari.

The topic is the environment.

It was published on Friday, July 24, 2026, at 9:25 pm.

In March 2025, yellow foam appeared on a beach in the Fleurieu Peninsula.

Here is a short summary:

A new report says three main things caused the harmful algal bloom.

The report found that floodwater, a coastal upwelling, and a marine heatwave caused the bloom.

What happens next?

The government will keep researching to fill in the gaps in the data.

After 18 months, the SA government has released a report about the algal bloom crisis.

The report says floodwater, a coastal upwelling, and a marine heatwave caused the bloom, but there was no single cause.

The South Australian Research and Development Institute did a preliminary investigation into the bloom.

The full report was released after an independent review.

The algal bloom was first seen in March 2025 and is known for its foamy and discolored water.

The report was released late.

The date on the report was May 15, but it was released later, which has been questioned.

Greens senator Sarah Hanson-Young said the SA government was too slow to act.

Sarah Hanson-Young says the SA government downplayed the impact of the toxic algal bloom.

When asked why the report was late, Minister Clare Scriven said it needed to be reviewed.

The report was reviewed by independent experts from Tasmania and the US.

But ecologist Faith Coleman said the report did not need to be peer-reviewed and should have been released sooner.

Faith Coleman welcomed the government's transparency and said the findings will be useful.

Faith Coleman has asked the government to release more data.

The report's findings

The report says three main things caused the bloom: floodwater, a coastal upwelling, and a marine heatwave.

The bloom developed during a marine heatwave.

The report says the heatwave and calm conditions helped the bloom grow.

The bloom happened after a long time of environmental changes.

Professor Mike Steer said a lot of research went into the report.

Understanding the causes of the bloom is important for predicting future blooms.

Mike Steer says there are gaps in the data.

Professor Steer was surprised by how quickly the report was finished.

Minister Clare Scriven said the research will help prepare for future blooms.

Clare Scriven says nothing can be done to prevent a harmful algal bloom.

Faith Coleman has asked the government to release more data.

Faith Coleman said the report is not a thorough review of the science.

She wants the government to release data on other hazardous species.

Faith Coleman hopes the government will change how it talks about the Murray River.

The Murray River was blamed for the bloom, which affects how it is managed.

There is a gap in the data

Professor Steer said there is still a lot to learn and it will take time.

The algal bloom hurt South Australia's coastline and killed many marine animals.

Answering one question in science often raises more questions.

The report is a good start for future research.

The new office will study topics like the biochemicals produced by the bloom.

The office will work with other countries to understand the impact of the bloom.

The report will help deal with similar crises in the future.

The focus now is on improving science to be better prepared.

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