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A health warning has been issued for all of Lake Rotorua and Ōhau Channel due to a significant rise in cyanobacteria concentration, Health NZ says.
Routine water monitoring results provided by the Bay of Plenty Regional Council detected high levels of cyanobacteria – the blue-green algae bloom visible in thewater.
Dr Greg Evans, Medical Officer of Health for the National Public Health Service Bay of Plenty/Lakes, said people should avoid any activity which results in contact with the lake water “in any shape or form”.
Blooming blue-green algae. Photo / 123RF
“If people do come into contact with water at lakes with health warnings or where there are visible changes in water colour, shower and change your clothing as soon as possible afterwards, even if you do not have symptoms.
“If you feel unwell after coming in contact with the lake, you should seek health advice from your doctor or by calling Healthline on 0800 611 116,” Evans said.
Contact with algal blooms can cause asthma and hay fever symptoms in some people, 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.
Ōhau Channel looking towards Lake Rotorua. Photo / File
Warning signs will be erected at Lake Rotorua advising potential lake users about the algal bloom and monitoring will continue, Health NZ said.
Parents were advised to keep an eye on children near the water as algal bloom scums can form at the edge of the lake, and children will sometimes play with them.
Dog owners should prevent their dogs from drinking or swimming in the water or eating algal bloom scum as dogs are particularly sensitive to cyanobacteria and could become seriously ill.
