The Central Basin and West Basin of Lake Burley Griffin have been closed to swimming and other high-contact activities due to extreme levels of blue-green algae.

The closures apply to all primary contact recreation, including activities involving full immersion such as swimming, bathing and sports like windsurfing, where there is a higher risk of swallowing water, the National Capital Authority said on Friday.

The NCA is urging people undertaking secondary contact activities, such as rowing and canoeing to limit exposure to the water and shower immediately after contact.

Weston Park East remains open, but a medium-level blue-green algae alert is in place.

All other areas of the lake are open, however the NCA is warning pet owners not to allow animals to swim in or drink from water where algal scum is present.