Dangerous Algae Detected Near Te Anau Milford Highway

Environment Southland has detected toxic algae in the Upukerora River at Te Anau Milford Highway, prompting a health warning for water users.

The regional council's monitoring team discovered the harmful algae during routine observations. Officials warn that similar algae growth may be occurring in other waterways across Southland.

Toxic algae appear as dark green or brown slime on rocks, or dark brown and black mats at the water's edge. While most algae are harmless, some species produce toxins and can rapidly bloom to dangerous levels during fine weather and stable river flows.

Environment Southland says water users should avoid all contact with the algae, which can pose significant health risks to people and animals if swallowed or through skin contact.

"Keep dogs on the lead and children away from affected areas," the council advises. "See a doctor immediately if you experience health symptoms after contact with contaminated water."

Pet owners are urged to take animals to a vet immediately if they consume toxic algae or contaminated water.

The council cannot monitor every waterway in the region, so encourages river users to learn what toxic algae looks like and stay informed through their website.

Photos and detailed descriptions of toxic algae are available at www.es.govt.nz/toxic-algae.

Environment Southland's communications team can be contacted on 0800 76 88 45 for more information about the algae alert.