Red toxic algae warning for Waikanae River at Jim Cooke Park

A red alert level warning for toxic algae is in place for the Waikanae River at Jim Cooke Park. Toxic algae, or cyanobacteria, is harmful to humans and lethal for dogs if ingested. 

Greater Wellington senior advisor integration and insights Penny Fairbrother says there are moderate amounts of detached algal mats accumulating at the river’s edge.  

“Detached mats pose the greatest risk to people and pets. We strongly advise everyone to avoid contact with water, and for dog walkers to avoid walking near the river at Jim Cooke Park,” says Fairbrother.  

“Dogs love the musty smell of algal mats as they dry on the river’s edge, and it can be hard to keep them away. Even a very small amount of toxic algae, the size of a 50-cent coin, is enough to kill a dog.” 

“For the time being, we recommend visiting other Kāpiti river areas, where toxic algae levels remain very low.”  

Dog owners who think their animals have swallowed toxic algae, or shows signs of lethargy, muscle tremors, fast breathing, paralysis or convulsions, should go to the nearest vet immediately.    

People who have been in contact with toxic algae and are feeling unwell, should see a doctor or ring Healthline on 0800 611 116.

Toxic algae grows on rocks in the riverbed and form leathery dark green or black mats, which can lift from the rocks and float on the surface. 

Greater Wellington is urging the community to check for LAWA website warnings and alerts before visiting rivers in the Wellington region this summer. 

Greater Wellington is currently monitoring popular river swimming spots for toxic algae on a weekly basis.   

Learn more about toxic algae 

Check for toxic algae alerts at the LAWA website