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.