BLUE-green algae levels have increased in the Metung area leading to authorities to warn against coming into contact with the water.
Metung Marina, Tambo Bay, Chinamans Creek and Metung beach areas have returned high readings which has triggered the health warnings.
Regional incident co-ordinator Daniel Mainville said people were relieved to see lower levels recorded across the Lakes system a fortnight ago but there was always the possibility the levels would rise during summer.
"This is why we're conducting regular tests across the Lakes system, so we can immediately advise the public when levels rise above the point at which human health might be at risk," Dr Mainville said.
The Lakes Entrance, Eagle Point and Jones Bay areas and areas west of Paynesville remain at low levels and are safe for recreational water use. Lake Tyers is free of blue-green algae.
Mussels, prawns and crabs caught anywhere in the Lakes system are not safe for human consumption, the Health Department warns.
