Blue-green algae concentrations have increased significantly in the Lachlan River arm of the storage with the potential to move through the storage.

A red alert level indicates people should not undertake recreational activities where they may come into direct contact with the water such as swimming, as well as domestic use including showering and washing.

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

The species of blue-green algae identified are potentially toxic and may cause gastroenteritis in humans if consumed and skin and eye irritations after contact.

Boiling the water does not remove algal toxins.

People are advised not to enter the water, not to drink untreated water or bathe in water drawn from the dam while this red alert level warning is in place.

Town water supplies remain unaffected and safe to drink.

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.

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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 generally has a strong musty or earthy odour.

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

Blue-green algae can 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, but 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.