The health warning for Lake Rotoiti has been partially lifted by the local Medical Officer of Health.
The warning remains in place for the Okere Arm and Okawa Bay at the western end of the lake.
Bay of Plenty Regional Council laboratory testing of recreational water showed the presence of potentially toxic levels of cyanobacteria or blue-green algae in the Okere Arm of the lake and at Okawa Bay, Toi Te Ora Public Health said in a statement today.
Laboratory tests also indicated algal blooms in other parts of the lake had subsided. Visual observations and satellite imagery provided by the Bay of Plenty Regional Council were consistent with the laboratory results, the statement said.
Despite the partial lifting of the warning, the public should always be cautious for signs of algal blooms if using lakes.