An amber alert has been issued for the Waikanae River near the old State Highway 1 bridge following the discovery of moderate levels of toxic algae at the site.

The amber alert follows a red alert issued downstream at Jim Cooke Park last week and highlights the importance of checking LAWA for safe swimming locations even as summer winds down.

Toxic algae is harmful to dogs and people. Eating just a small piece of toxic algae is enough to kill a dog, while people can become sick if they ingest it.

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. Avoid letting your dog scavenge on the riverbank.

Greater Wellington is currently monitoring 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, 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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