The health warnings issued for Lake Ohakuri and Lake Okaro in December have now been lifted by the local Medical Officer of Health.
Results of water testing by the Waikato and Bay of Plenty Regional Councils confirmed the algal blooms had subsided in the lakes.
Medical Officer of Health for Toi Te Ora Public Health Dr Phil Shoemack said despite the lifting of these warnings it was always important to look for signs of algal blooms before using lakes.
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"Algal blooms can develop rapidly and unpredictably and can sometimes produce toxins that are harmful for people as well as animals.
"If there is an obvious algal bloom, or the water looks discoloured, has an unusual smell, or has green or brown particles suspended in it, then it is best to avoid contact with it," he said.
Shoemack said experience showed that Lake Okaro was prone to algal blooms at any time of the year.
"Lake users must exercise caution and make their own judgement about water quality by looking at the colour and clarity of the water, and whether it smells at all.
"Laboratory testing of lake water by Bay of Plenty Regional Council only occurs on a weekly basis during summer months so it is important to look before you leap. If in doubt, it is best to avoid contact with the water and swim or play somewhere else," he said.