Marine algal red alert issued for Berowra Waters

Marine algal red alert issued for Berowra Waters

25 October 2019

A red alert level warning (high alert) for potentially toxic marine algae has been issued for the estuary at Berowra Waters.

A red alert level warning indicates that people should not undertake recreational activities where they may be coming into direct contact with the water.

Contact with the water may also pose a threat to livestock, and pets.

The algae bloom appears as an orange-red discolouration in the water.

People are advised not to enter the water, not to drink untreated water or swim in untreated water while a red alert level warning is in place. Boiling the water will not remove algal toxins.

People should also not eat mussels or crayfish from red alert warning areas.

Any fish caught should be cleaned and washed thoroughly in uncontaminated water and any internal organs disposed of before consumption.

It is not possible to predict how long the algae will remain at high levels.

Hornsby Shire Council is erecting signage and is monitoring the situation closely.

Regular water sampling will continue, and the alert will be lifted as soon as the high levels of algae dissipate.

People who suspect they may have been affected by algae are advised to seek medical advice.

For more information visit Hornsby Shire Council’s website –

Updates about blue-green algae or marine algae blooms and red level warning areas can be obtained by calling 1800 999 457.

WaterNSW media Contact – Tony Webber – 0428 613 478


Saturday 27 November
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Saturday 27 November