Algal Bloom in Rakahuri/Ashley River (Updated)
Clarification of affected area [further to last night’s media release]
Health Warning – Algal Bloom in Rakahuri/Ashley River around the Bridge on State Highway 1 near Waikuku
The Community and Public Health division of the Canterbury District Health Board have issued a health warning for Rakahuri/Ashley River in the areas around the Bridge on State Highway 1 near Waikuku.
The warning follows finding moderate cover with detaching mats of potentially toxic blue-green algae (benthic cyanobacteria) in the Rakahuri/Ashley River State Highway 1 bridge area.
People and animals, particularly dogs, should avoid the area of the Rakahuri/Ashley River State Highway 1 until the health warning has been lifted.
Dr Ramon Pink Canterbury Medical Officer of Health, says the algae look like dark brown to black mats and can produce toxins harmful to people and animals.
“Exposure may cause skin rashes, nausea, stomach cramps, tingling and numbness around the mouth and fingertips,” Dr Pink says.
“If you experience any of these symptoms, visit your doctor immediately, also let your doctor know if you’ve had contact with dark brown/black algal mats or water in this area.”
Reticulated town water supplies are currently safe but no one should drink water from the river at any time
Pets that show signs of illness after coming into
contact with algal mats should be taken to a vet
immediately.
Dr Ramon Pink
says people and animals should remain out of the waterways
until the warnings have been lifted.
Environment
Canterbury is monitoring the sites and the public will be
advised of any changes in water quality.
The existing warnings to remain out of the
following waterways due to ongoing algal blooms are still in
place:
• Te Waihora/Lake Ellesmere
• Selwyn River
at Whitecliffs Domain
• Selwyn River at
Glentunnel
• Ashley River Rangiora/Loburn
Bridge
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