Toxic algae in Waipoua River

  • Published Date 24 Dec 2015

Toxic algae has been found parts of the Waipoua River, near Masterton, prompting authorities to warn dog owners to keep their dogs on the lead and people to take care.

Monitoring of the Waipoua River at Colombo Road by the Regional Council shows that the amount of brown or black toxic algal mats growing on the river bed has reached moderate levels.  If ingested it can kill livestock and dogs and contact can cause vomiting, diarrhoea and skin irritations in humans.

"Despite some recent rain, flow in the Waipoua River is dropping and temperatures are warming up providing ideal conditions for algal growth" says Regional Council Environmental Science Team Leader Juliet Milne.

Masterton District Council has posted toxic algae information signs at key access points along the river. Monitoring of Wellington waterways and coastal areas is carried out by Greater Wellington Regional Council, Regional Public Health and local authorities on a weekly basis over the summer months. Results of the monitoring are posted


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Updated April 29, 2022 at 9:52 AM

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