The Excelsior Creek inflow on the Waiau River has become the latest Southland waterway to harbour toxic algae.

Elevated levels of toxic algae had earlier been found by Environment Southland (ES) staff at Hamilton Burn, a tributary of the Aparima River, on the Waiau River near Tuatapere and in the Waihopai River.

Warm temperatures, low stable flows, high levels of nutrients and run-off are all thought to contribute to the annual occurrence of Toxic algae (benthic cyanobacteria) in Southland waterways.

The algae presents as a dark green/brown slime on rocks, or dark brown/black mats at the water’s edge.

Water users and animals should avoid contact with algal mats and remain alert in other parts of the river for algal growth or mats of algae floating in the water.

ES advise that anyone who experiences health symptoms after contact with contaminated water, visit a doctor immediately. If you are concerned that any animals have consumed toxic algae or contaminated water, they should be taken to a vet immediately.

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