Elevated levels of the potentially toxic algae have now been found in the Whitestone River below Hillside Road.

Environment Southland currently has toxic algae alerts in place at the Waikaia River at Waikaia, Aparima River at Thornbury, the Waiau River upstream of Excelsior Creek, and Upukerora River near Te Anau where a family's dog died after suspected contact with the toxic algae.

While algae occurs naturally in waterways some species can, given the right conditions including warm weather and low river flows, produce toxins and rapidly bloom to harmful levels.

Toxic algae is commonly identified in waterways as a dark green/brown slime on rocks, or dark brown/black mats at the water’s edge. 

It can be harmful to people and animals if swallowed, or through contact with skin.

People and animals (it can be deadly to dogs, in particular) should avoid contact with the river and be mindful of the potential health risks, until health warnings are removed. 

If you experience 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.

ES regularly monitors toxic algae at a number of river and lake sites across Southland.

CLICK HERE for further information.