“The toxins can affect the nervous system causing numbness and difficulty with breathing, and also sparking asthma attacks. Contact with the water can also cause skin rashes, stomach upsets and visual problems.”
Shoemack said it was likely the algae bloom would be present for several kilometres along the Kaituna River as water from both lakes flowed into it.
He urged people to keep an eye out for blooms while using lakes and rivers in the Bay of Plenty and Lakes districts over summer.
“Algal blooms can develop rapidly and unpredictably. If the water looks discoloured, has an unusual smell, or has green or brown particles floating in it then it is best to avoid contact with it.”