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Warning now lifted from Lake Hakanoa
Warning now lifted from Lake Hakanoa
The health warning has now been lifted for Lake Hakanoa, but warnings remain in place for three other regularly tested lakes outside Hamilton. These lakes are Ngaroto, Waikare, and Whangape. Waahi had its health warning lifted in February and the biovolume remains very low in that lake.
Lake Rotoroa in Hamilton also has no health warning at present, as cell counts have been low over the summer.
Waikato Regional Council is no longer routinely testing Lake Kainui but caution is always advised for users of this lake, because of its history of cyanobacterial blooms.
As always, these test results should be used for general guidance only, as cyanobacteria and their toxins will not be evenly spread through any lake and may be concentrated in some areas by wind and water movements. Cyanobacterial blooms can happen very quickly when conditions for growth are favourable, and it is possible that the recent unusually warm weather, if sustained, may encourage cyanobacterial growth.
During blooms, lakes should not be used for any activity which involves skin contact with the water,” said Dr Hood. Scums are a particular risk and contact with scums should be avoided. If contact does occur, skin should be rinsed clean and clothing changed as soon as possible. Because of their small size, this warning is particularly important for children.
Swallowing water from lakes affected by blooms should also be avoided.
“If people still choose to use the lakes when warnings are in place, they should shower and change their clothing as soon as possible afterwards, even if no symptoms are noticeable.”
While not everyone will be affected, for some, the risks include rash, skin and eye irritation, allergy symptoms such as hayfever and asthma and possibly stomach upsets such as diarrhoea and vomiting.
These effects may not appear until some time after contact with the affected water. Long term exposure to cyanobacterial toxins may bring additional health risks. Scums on any lake are likely to contain high levels of toxin.
The Waikato DHB Population Health Service would like to be informed about health problems which develop after exposure to any of the Waikato lakes.
“Up-to-date information on cyanobacterial cell counts is available from local councils and Waikato Regional Council. The Waikato Regional Council website: http://www.waikatoregion.govt.nz/Environment/Natural-resources/Water/Rivers/Waikato-River/Algal-Blooms-in-the-Waikato-region/
Health advice is available from the Population Health Service (07) 839 8899 in and out of hours.
ENDS
Waikato District Health Board
Healthy People. Excellent Care
Waikato District Health Board (DHB) employs over 6500 people and plans, funds and provides hospital and health services to more than 391,770 people in a region covering eight per cent of New Zealand.
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