Blue Green Algae

Blue-green algae are a type of bacteria known as Cyanobacteria. Most blue-green algae species are safe or non-toxic, however some species are considered toxic and care should be taken to eliminate any contact with the affected water body.

Blue-green algae can occur in rivers, dams, lakes such as Blackburn Lake or Surrey Dive. The algae occurs more often when the water is still and the weather or water is warm.

The term "algal bloom" is used to describe a large number of cells that discolour the water bluey-green. It can be thick and have an unpleasant taste and smell. Blue-green algal blooms often last for several weeks, sometimes months, depending on the weather and water flow conditions. Algal blooms take oxygen out of the water which can kill fish and harm other animals.

As an algal bloom dies, the cells tend to become 'leaky' and, if the algal bloom produces toxins, the toxins will be released into the surrounding water. Once released, some toxins may persist in the water for more than three months.

Please contact Council if you see suspected blue-green algae in a creek or dam in the city of Whitehorse.

Health Risks

Blue-green algae toxins may cause health problems for people, domestic animals and stock that come into contact with the algae.

There have been reports of skin and eye irritations, nausea, vomiting, muscle weakness or cramps by some people who have swim through algal scum or swallowed it.

Blue-green algae blooms can cause:

  • Harmful human health effects
  • Death of livestock
  • Domestic animals and wildlife
  • Bad odours
  • Fish kills
  • Closure of water storages for drinking or recreational use
  • Higher water treatment costs

Do not swim, wade, fish or drink from water bodies that have blue-green algal blooms and do not let dogs and other animals wade or swim in affected water.

If you come in contact with affected water wash yourself and any clothing thoroughly with clean water.

If you are worried about your health or have been in contact with blue-green algae please contact your doctor.

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Blue-green Algae

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