Toxic Algae Warning for Waiau RiverToxic Algae Warning for Waiau River

Environment Southland has issued a warning after detecting toxic algae in the Waiau River near the Excelsior Creek inflow. While algae naturally occur in waterways, certain types can produce harmful toxins, especially during stable river flows and fine weather.

Toxic algae can appear as dark green or brown slime on rocks or as dark brown or black mats along the water’s edge. These algae pose risks to humans and animals if ingested or through skin contact.

A spokesperson said: “We encourage river users to familiarise themselves with the signs of toxic algae. Our website provides photos and descriptions to help identify these potentially harmful blooms.”

While Environment Southland monitors water quality, algae growth varies and may occur in areas not regularly tested. Residents and visitors are urged to check local conditions, avoid contact with the algae, and keep dogs and children away from affected areas.

The spokesperson added: “Anyone experiencing symptoms after contact with contaminated water should seek medical attention. Likewise, animals showing signs of illness after exposure should be taken to a vet immediately.”

For detailed information and images, visit the Environment Southland website: www.es.govt.nz/toxic-algae. For further inquiries, contact the communications team at 0800 76 88 45.