Health warnings issued for Lake Ohakuri and Lake Maraetai

A health warning has been issued for Lake Ohakuri and Lake Maraetai. Samples taken from both lakes by Waikato Regional Council have confirmed a bloom of potentially toxic blue-green algae.

Today’s health warning is an update and extension of the health warning issued yesterday for Lake Ohakuri after a visual assessment by the regional council indicated a suspected algal bloom.

“Members of the public should avoid any activity which results in significant contact with the water in the lakes,” says Dr Jim Miller, Medical Officer of Health.

Contact with water affected by blooms of blue-green algae can cause asthma and hayfever attacks in some individuals.  Contact with the blue-green algae can also cause skin rashes, stomach upsets, and in some cases neurological effects such as tingling around the mouth, headaches, breathing difficulties and visual problems.

Signage has been erected at both lakes advising potential lake users about the algal bloom. 

Dr Miller advises the public to always watch out for signs of algal blooms if using lakes. Signs to look out for include discoloured water, an unusual smell, or green or brown floating algae particles.

Up-to-date information on health warnings for the Bay of Plenty and Lakes districts is available through these channels:


For information on health alerts for Waikato district, visit the Waikato DHB website or contact Waikato Health Protection on 07 838 2569.

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