THE ACT government has issued an extreme alert level for blue-green algae in Lake Tuggeranong, closing the water for primary-contact activities such as swimming, diving, water skiing and windsurfing.

Secondary-contact recreation such as rowing, fishing, boating and canoeing are permitted, however, individuals are advised to avoid water contact as much as possible and shower after contact. 

It is also strongly advised that contact with any algal scum is avoided, and clothing that has been in the water be washed to remove algae residue. 

The government says water event organisers should ensure all participants are aware of the alert and the risks involved.

Pet owners are also advised to not allow their animals to swim in or drink the water as it can make them extremely ill and even result in death.

Symptoms of algae exposure may include skin, mucosa and eye irritation, flu-like symptoms, hay fever-like symptoms and gastrointestinal illness. Anyone concerned about possible symptoms of blue-green algae exposure following water exposure should contact their GP.

Water users are also reminded that algae levels can change quickly and should look for algae warnings signs which indicate the current algae alert level.