Health warning removed for algal blooms in the Selwyn/Waikirikiri River at Glentunnel and the Hurunui River at State
Highway 7
The Community and Public Health division of the Canterbury District Health Board has lifted its algal bloom health
warnings issued for the Selwyn/Waikirikiri River at Glentunnel and the Hurunui River at State Highway 7
Recent cyanobacteria surveying of the water in the Selwyn/Waikirikiri and Hurunui Rivers has shown the quantity of
potentially toxic blue-green algae (benthic cyanobacteria) in the river has decreased and are now below the levels that
are of concern to public health.
Dr Ramon Pink, Canterbury Medical Officer of Health, says Environment Canterbury's routine monitoring of rivers in the
Canterbury region has been completed for this summer season.
"It will resume again next summer when there is increased likelihood of cyanobacteria growth," Dr Pink says.
"The public is however reminded that there are still some lakes where warnings remain in place due to algal blooms."
The warnings remain in place at the following waterways due to ongoing algal blooms;
Lake Ellesmere (Te Roto o Waihora)
Lake Forsyth (Te Roto o Wairewa)
Lake Pegasus
Facts about cyanobacteria:
Appears as dark brown/black mats attached to rocks along the riverbed.
The algae occur naturally but can increase rapidly during warmer months.
It often has a strong musty smell and algal toxin concentrations can vary over short periods with changing environmental
conditions.
Although high river levels will remove the algal bloom, detached mats can accumulate along the shore and increase the
risk of exposure to toxins.
If a health warning is in place avoid contact with the water.
Although district or city councils may place warning signs, these may not be seen at the numerous river access points,
hence the need for people/ dog-walkers to treat every low-flowing river cautiously.
For further information visit https://www.ecan.govt.nz/your-region/your-environment/water/swimming-water-quality/
Or contact Community and Public Health on (03) 364 1777.
For more information on Mahinga kai:
Gathering Mahinga Kai
ENDS