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 Toi Te Ora Public Health warning is an update and extension of the warning issued yesterday for Lake Ohakuri after a visual assessment by the regional council indicated a suspected algal bloom.
Lake Ohakuri is located on the Waikato River between Ātiamuri and Waikite. Lake Maraetai is also on the river, located near Mangakino.
Medical Officer of Health Dr Jim Miller said people "should avoid any activity which results in significant contact with the water in the lakes".
Contact with water affected by blooms of blue-green algae can cause asthma and hay fever 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.
Miller said people using lakes should always watch out for signs of algal blooms, including 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:
Phone: 0800 221 555
Website: www.ttophs.govt.nz/health_warnings
Fact Sheet: www.ttophs.govt.nz/vdb/document/43
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