AGL closes Lake Liddell due to health risks

AGL Macquarie advises the community that due to a risk of infection from naegleria fowleri, Lake Liddell has been closed until further notice.

These carry a serious risk of harm to humans if they enter the body via the nose.

Lake Liddell is located approximately 15 kilometres south of Muswellbrook, just off the New England Highway.

It supplies cooling water to two nearby power stations, and is also a recreational facility.

Lake Liddell

Lake Liddell

Naegleria fowleri is an amoeba that lives predominantly in warm freshwater.

Following routine water monitoring by AGL at Lake Liddell, amoeba were found. 

AGL has notified all relevant authorities and the nearby recreation park at Lake Liddell.

The lake will be closely monitored. 

Naegleria are free-living protozoa that occupy a range of thermal niches in sediments, fresh water, sewage and sludge.

More than 40 Naegleria species have been identified, and some are thermophilic (heat tolerant), and able to grow at temperatures as high as 460 C.

Naegleria fowleri, can cause an infection called primary amoebic meningoencephalitis (PAM), an often fatal disease of the central nervous system. 


  • Naegleria fowleri are single-celled organisms (amoebae) that are found in warm fresh water bodies around the world;
  • Naegleria fowleri can cause a very rare infection of the brain, which is usually fatal; 
  • Infection can occur if water containing amoebae is pushed up the nose, through activities such as jumping, diving or falling into the water;
  • There is an extremely low risk from treated water supplies in Australia;
  • Recent cases of Naegleria fowleri in Australia were in private water supplies that were untreated or poorly treated;
  • Well-treated town water supplies with effective disinfection (such as chlorine) are not at risk from this organism.