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Health warning lifted for Te Wairewa – Lake Forsyth

Friday 25 November 2016Media release2 minutes to read

The Community and Public Health division of the Canterbury District Health Board has lifted its algal bloom health warning issued for Te Wairewa / Lake Forsyth on 25 November 2016.

Recent water testing at Te Wairewa / Lake Forsyth has shown the quantity of potentially toxic blue-green algae (Anabaena and Nodularia) in the lake has decreased and concentrations are now below the levels of concern to public health.

Dr Alistair Humphrey, Canterbury Medical Officer of Health, says Environment Canterbury's sampling of Te Wairewa / Lake Forsyth will continue on a fortnightly basis over the summer months and the public will be notified if there is a risk to public health again.

Facts about cyanobacteria:

The algae occur naturally but can increase rapidly during warmer months.
If the water is cloudy, discoloured, or has small globules suspended in it, avoid all contact.
Not all cyanobacterial blooms are visible to the naked eye and toxins can persist after the blooms disappear.
Cyanobacterial concentrations can change quickly with changing environmental conditions (e.g. wind). If a health warning is in place avoid contact with the water.
If a warning is in place, people and animals should not drink the water from the lake at any time, even boiled water.
Exposure to an algal bloom can cause skin rashes, nausea, stomach cramps, tingling and numbness around the mouth and fingertips. If you experience any of these symptoms visit your doctor immediately and please let your doctor know if you have had contact with lake water when there is a health warning in place.
For further information visit Environment Canterbury's website

Or contact Community and Public Health on (03) 364 1777.



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Page last updated: 19 December 2018

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