Toi Te Ora Public Health has issued a health warning for Lake Rotorua as testing by the Bay of Plenty Regional Council has confirmed a bloom of potentially toxic blue-green algae.
The health warning means that people should avoid any contact with the lake water.
Contact with algal blooms can cause asthma and hayfever attacks in susceptible individuals, as well as skin rashes, stomach upsets, and in some cases neurological effects such as tingling around the mouth, headaches, breathing difficulties and visual problems.
Monitoring will continue and this warning will be updated as needed.