Blue-green algae Red Alert for Clarrie Hall Dam on the North Coast

Blue-green algae Red Alert for Clarrie Hall Dam on the North Coast

15 January 2021

A Red Alert warning (high alert) for blue-green algae has been issued for Clarrie Hall Dam by Tweed Shire Council due to increasing concentration of blue-green algae in the storage.

Warning signs have been erected at key recreational areas that will remain in place while high levels of blue-green algae are present. This alert does not affect Tweed Shire Council drinking water supplies, which remain safe to drink.

A Red Alert level warning indicates that people should not undertake recreational activities where they may come into direct contact with the water, such as swimming or watersports. Contact with the water may also pose a threat to livestock and pets.

People are advised not to enter the water, swim or bathe in water, or drink untreated water drawn from the lake while the Red Alert level warning is in place.

Livestock owners are reminded to continue to check stock water supplies for blue-green algae and to remove stock from foreshores where surface scum is visible or blue-green algae are suspected.

People should 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.

Blue-green algae usually appear as green paint-like scums on the water, near the edges, or as greenish clumps throughout the water. It makes the water appear dirty, green or discoloured and may have a strong musty or earthy odour.

Blue-green algae occur naturally and can reproduce quickly in favourable conditions where there is still or slow-flowing water, abundant sunlight and sufficient levels of nutrients.

It is not possible to predict how long the algae will remain at high levels. Regular monitoring will continue, and the alert will be lifted as soon as the high levels of algae dissipate.

People who believe they may have been affected by blue-green algae are advised to seek medical advice.

Updates about blue-green algae blooms and Red Alert level warning areas can be obtained by calling 1800 999 457 or at or

Media Contact – Tony Webber – 0428 613 478


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