People and their pets are being urged to avoid stormwater ponds and wetlands in Christchurch as they could contain the potentially toxic algae, cyanobacteria.

Christchurch City Council Head of Three Waters and Waste Helen Beaumont says the algae has been confirmed in at least one pond and maybe present in others.

“As we head into the summer and warmer weather, it is likely that we’ll find more toxic algal blooms, particularly as we have had a long period of low rainfall.’’

The algae typically presents as dark brown or black mats in the water.

“If you’re going for a walk around one of our wetlands or stormwater basins, please avoid contact with the water as we can’t guarantee there isn’t potentially toxic algae in it. We don’t want either you or your pet to get sick,’’ Ms Beaumont says.

Human exposure to cyanobacteria may cause skin rashes, nausea, stomach cramps, tingling and numbness around the mouth and fingertips. If you experience any of these symptoms, visit your doctor immediately.

Pets that show signs of illness after coming into contact with algal mats should be taken to a vet immediately.