Elevated levels of toxic algae have been found at Hamilton Burn, by Affleck Road, according to Environment Southland.

People and animals (dogs in particular) should avoid contact with this waterway and be mindful of the potential health risks, until health warnings are removed.

Toxic algae (benthic cyanobacteria) can appear in rivers and streams as a green/brown slime on rocks, or dark brown/black mats at the water’s edge.

High levels of nutrients, run-off into waterways, a sudden increase in temperature or low flows can all contribute to the growth of this algae.

Environment Southland senior scientist Roger Hodson said 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”.

These algae can produce toxins that are harmful to people and animals if swallowed, or through contact with skin.

Anyone experiencing health symptoms after contact with contaminated water should visit their doctor immediately while animals should be taken to a vet.

Click here for further information www.es.govt.nz/toxic-algae