Dangerous levels of toxic algae have been found in the Waikanae River prompting Greater Wellington to strongly advise the public not to swim in near Jim Cooke Park.

A red alert has been issued on the Land, Air, Water Aotearoa (LAWA) website at the swimming site near the park where detached algal mats have also been detected.

Toxic algal mats grow on rocks in the riverbed and form leathery dark green or black mats, which can break off and accumulate on the riverbank.

As detached algal mats dry out, they become light brown and emit a distinctive musty odour that attracts dogs.

Dog owners walking near these sites should keep their animals leashed. Do not let your dog scavenge on the riverbank. Eating a tiny algal mat can kill a dog.

Greater Wellington monitors popular swimming spots on a weekly basis to make sure the community knows when and where it’s safe to swim.

To know if an area is suitable for swimming visit the LAWA website and check for warnings and alerts in the Wellington region.

To learn how to identify toxic algae visit Greater Wellington’s toxic algae webpage.

If you have been in contact with toxic algae and are feeling unwell, see your doctor or ring Healthline on 0800 611 116.

If you think your dog has swallowed toxic algae and it’s having difficulty breathing, take it immediately to the nearest vet.

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