Health warning removed for algal bloom at Hurunui River

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 7. This was issued on February 15, 2016.

Recent water testing at Hurunui River has shown the quantity of potentially toxic blue-green algae (benthic cyanobacteria) in the river has decreased and concentrations are now below the levels that are of concern to public health.

Dr Ramon Pink, Canterbury Medical Officer of Health, says Environment Canterbury’s sampling of Hurunui River has finished for the season and will resume next summer when there is increased likelihood of cyanobacteria growth.

Facts about cyanobateria:

• 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 Environment Canterbury’s website.

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