A blue-green algal alert has been issued by Eurobodalla Shire Council today for Lincoln Downs Lake, Surfside.

Council's Divisional Manager for Environmental Services, Deborah Lenson, says the algae numbers are in the high range and could pose a potential health risk to people and animals.

"Some people may have noticed a musty odour in the area caused by the high level of algae in the lake," said Ms Lenson.

"The levels are high due to the unseasonably warm weather, the shallowness of the lake and the urban stormwater that drains into the lake, all of which are perfect conditions for algal growth," said Ms Lenson.

Warning signs have been placed in the affected areas.

Ms Lenson says Eurobodalla residents and visitors should avoid any activities on the lake that will bring them into contact with the water such as swimming or fishing.

Pets should also stay out of the water as blue-green algae have the potential to kill animals. "Dogs are particularly susceptible as they can ingest algae when they lick their coats," Ms Lenson said.

Blue-green algal growth looks like clumps of dirty green paint scum on the water and has a strong odour. The toxins in it can cause severe stomach upsets, nausea and skin irritation and cannot be removed by boiling the water.

If you believe you have been affected by the algae, please seek medical treatment. Council will continue to monitor the algal bloom and will update the community as the situation changes.