Water quality in the ACT

Lake Tuggeranong in the ACT

The ACT has many types of recreational water bodies, such as lakes, ponds and rivers. 

Popular recreational water bodies include:

  • Lake Tuggeranong
  • Lake Ginninderra
  • Murrumbidgee River Corridor
  • Molonglo River, and 
  • Paddy’s River

Contaminated stormwater can affect water quality and pose the following health risks:

  • gastroenteritis
  • respiratory illness
  • ear infections, and 
  • skin and eye problems. 

Please contact your GP if you experience any of these symptoms after swimming in recreational water bodies.

To protect the community, ACT Health collects samples from these water bodies to check its quality. This activity occurs every year from September to April. The samples get delivered to our laboratories for analysis and all results are published on the Transport and City Services website.

The ACT Chief Health Officer may authorise to close a recreational water body, or part of it, if there is a potential risk to public health.

The community is also advised to check public information and signage near water bodies before undertaking water-based activities. 

Blue-green algae

Blue-green algae (or cyanobacteria) in Sullivans Creek, Canberra, ACT
Blue-green algae in Sullivans Creek, ACT (Source: CSIRO)

Blue-green algae, or cyanobacteria, usually grow on the surface of water. Low numbers of blue-green algae are a normal part of the ecosystem in most waterways, including lakes, rivers, creeks and wetlands.

'Bloom' is the term used to describe an accumulation of algal cells to a point where they discolour the water, form scums, produce unpleasant tastes and odours and reduce the water quality. Drought and increased temperature in summer may result in an increase in visible ‘blooms’ and surface scums on waterways.

Some types of blue-green algae can produce toxins that may be harmful to humans and animals.

Exposure can occur through:

  • Direct contact of skin, eyes, mouth or nose with affected water during water-based recreational activities such as swimming, diving, water-skiing, windsurfing, canoeing, rowing or other boating activities
  • Breathing in fine water spray or droplets created when the surface of affected water is broken during water-based recreational activities
  • Accidental swallowing of affected water
  • Consumption of fish or other seafood from affected waterways

The possible health effects vary with the type of toxin and the route of exposure including:

  • Direct skin contact with blue green algae toxins can cause skin and eye allergic reactions or irritation
  • Accidental swallowing of affected water or consumption of food from affected water can cause symptoms of gastroenteritis, including nausea, vomiting, diarrhoea, fever and abdominal pain. In extreme cases, damage to liver cells and nerve cells can also occur
  • Breathing in fine water spray or droplets from affected water during recreational water activities can cause asthma or hay fever-like symptoms

To avoid potential exposure to blue-green algae it is important to:

  • Follow the advice of any information signs around affected waterways
  • Avoid any recreational activities that could involve contact with affected water
  • Do not eat fish or seafood from any waterway that has been affected by blue-green algae in the past 3 months
  • Do not let pets drink or swim in blue-green algae affected water
  • Closely monitor children and pets near affected waterways and keep them well away from the edge of the water

If you have had skin contact with affected water, immediately remove any wet clothing and wash or rinse any body part that has been in contact with the affected water. If you feel unwell, see your GP. For more information, refer to our Blue-green algae fact sheet.

More information

The ACT Guidelines for Recreational Water Quality provides a framework for the management of recreational water sites within the ACT. It addresses risks such as blue-green algae and microbial pathogens.

Page last updated on: 9 Dec 2019