Lake warnings

We monitor more than 100 popular recreational sites in Canterbury during summer. Health warnings are placed at sites where an increased risk of cyanobacteria or faecal contamination is present. Advisory notes may be present but are not an official public health warning.

Cyanobacteria can occur in any waterway, at any time, so it is important that you know what it looks like. Find out more about cyanobacteria in waterways and how you can protect yourself and your animals.

Faecal contamination poses a risk to health, check out LAWA’s swim smart checklist, to know what to check before you swim.

Pegasus Lake

10 December 2021
 

Canterbury DHB’s Community and Public Health unit has issued a health warning after potentially toxic blue-green algae (planktonic cyanobacteria) was found in Pegasus Lake.

People should avoid the lake and animals, particularly dogs, should not be allowed near the water until the health warning has been lifted.

Environment Canterbury continues to monitor the lake on a regular basis.

Wainono Lagoon

03 December 2021
 

Canterbury DHB’s Community and Public Health unit has issued a health warning after potentially toxic blue-green algae (planktonic cyanobacteria) was found in Wainono Lagoon.

People should avoid the lake and animals, particularly dogs, should not be allowed near the water until the health warning has been lifted.

Environment Canterbury continues to monitor the lagoon on a regular basis.

Algal Bloom in Te Roto o Wairewa (Lake Forsyth)

19 October 2021
 

Canterbury DHB’s Community and Public Health unit has issued a health warning after potentially toxic blue-green algae (planktonic cyanobacteria) was found in Te Roto o Wairewa (Lake Forsyth).

People should avoid the lake, and animals, particularly dogs, should not be allowed near the water until the health warning has been lifted.

Dr Cheryl Brunton, Canterbury Medical Officer of Health, says the algal bloom can produce toxins harmful to humans and animals.

Environment Canterbury continues to monitor the lake on a regular basis.

Lake Rotorua (near Kaikoura)

Last updated 8 March 2019
 

Long term water testing indicates that there is a regular bloom of the potentially toxic cyanobacteria Anabaena and/or Microcystis present.


There is a permanent health warning advising people to avoid contact with water at this lake.


Environment Canterbury continues to monitor the lake on a regular basis.