Health warning removed for algal bloom in the Hurunui River
Health warning removed for algal bloom in the Hurunui
River at State Highway 1
The Community and Public
Health division of the Canterbury District Health Board has
lifted its algal bloom health warning issued along the
Hurunui River at State Highway 1. This was issued on the
12th January 2017.
Recent cyanobacteria surveying for the
Hurunui River at SH1 has shown a decrease in potentially
toxic blue-green algae mats (benthic cyanobacteria) in the
river and the cover is now below the levels that are of
concern to public health.
Canterbury Medical Officer of Health Dr Alistair Humphrey says Environment Canterbury’s monitoring of the Hurunui River will continue to the end of this summer and then will resume next summer when there is increased likelihood of cyanobacteria growth.
A warning remains in place for the Hurunui River near SH7.
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.
ends