Be mindful of blue-green algae this summer

Tuesday 12 December, 2023

With the warmer weather arriving, Goulburn-Murray Water (GMW) encourages people visiting its lakes, dams, and reservoirs to check for blue-green algae warnings and take the necessary precautions.

GMW regularly tests for blue-green algae across its storages and distribution systems, issuing warnings when blue-green algae levels exceed a certain threshold.

Water Quality Coordinator Bianca Atley said people must heed these warnings for their safety.

“We see more blue-green algae warnings during the summer, which coincides with when a lot of people are visiting our storages, so it is important to check for warnings before you leave and adjust your plans accordingly,” she said.

“Blue-green algae contain toxins that can be harmful to people and animals that come into contact with it or swallow water containing it.

“Often, the symptoms from algae exposure can take up to a week to occur, so people do not always recognise it as the reason they have gotten sick.”

People coming into contact with water containing high levels of blue-green algae may experience rashes; sore eyes, ears, and nose; asthma; numb lips and limbs; nausea, vomiting, or diarrhoea. Anyone experiencing symptoms should seek medical attention.

Despite its toxicity, blue-green algae are naturally occurring.

Low levels of blue-green algae are present in water all the time. Warnings are issued when samples exceed the maximum level considered safe for humans.

Ms Atley said while it was not possible to predict how long a warning would remain in place, blue-green algae levels did tend to change at certain rates.

“While blue-green algae levels can increase rapidly, the rate of decline is often gradual,” she said.

“Occasionally, people think it is safe to get in the water when a warning is in place because there is no discernible change to the colour of the water.

“However, high levels of blue-green algae are not always visible, and levels can only accurately be determined through testing, so it is crucial when people see a warning that they play it safe.

Warnings can be found 24 hours a day on the GMW blue-green algae hotline, call (03) 5826 3785 and on the GMW website: https://www.g-mwater.com.au/news/bga