Algal bloom triggers new health warning for Lake Rotorua at Holdens Bay

A health warning has been issued for Lake Rotorua at Holdens Bay. Photo / NZME

A new health warning was issued for one Lake Rotorua bay on Friday while one of two Lake Rotoiti health warnings was removed.

A health warning has been issued for Holdens Bay at Lake Rotorua due to the discovery of potentially toxic blue-green algae.

Toi Te Ora Public Health issued the health warning on Friday based on the results for levels of cyanobacteria in water samples, visual assessments and satellite imagery provided by the Bay of Plenty Regional Council.

Toi Te Ora Public Health medical officer of health Dr Lynne Lane said it was important to avoid any activity which could result in contact with the lake water.

“Contact with water affected by blooms of blue-green algae can cause asthma and hayfever attacks in some individuals,” Lane said.

“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.”

The public health warning at Okawa Bay, Lake Rotoiti has been lifed. Photo / Andrew Warner

Lane said it was especially important for children to avoid contact with any algal mats and scum which could also accumulate along the shoreline of the lake.

“Dogs are particularly at risk and should also be kept away from the shoreline. Elsewhere in New Zealand there have been reported deaths of dogs that have eaten algae on shorelines.”

Meanwhile, Toi Te Ora has lifted the health warning in place at Okawa Bay at the western end of Lake Rotoiti.

The warning was lifted after water test results and visual observations provided by the Bay of Plenty Regional Council indicated the algal bloom at the bay had cleared.

The warning for Lake Rotoiti at the Okere Arm remains in place.

Signage is erected at sites along the shore of the bay advising potential lake users about algal blooms.

Lane advised the public to keep an eye out for signs of algal blooms if using lakes in our region.

“Algal blooms can develop rapidly and unpredictably and can sometimes produce toxins that are harmful for people as well as animals. If the water looks discoloured, has an unusual smell, or has green or brown particles floating in it then it is best to avoid contact with it.”