Another South West lake will remain off limits after toxic blue-green algae was confirmed by recent tests.

Lake Burrumbeet has been closed to the public following reports of the lake water becoming green.

The Ballarat Council said the lake will remain closed until two successive water samples return results of lowered levels of bacteria.

They said the lake is closed for swimming, water sports, wading and fishing.

Extracting water for stock or domestic use is also been banned along with allowing pets to make contact with or drink the water.

Water will continue to be tested and monitored weekly.

Signs posts warning of the lake's closure have been installed at boat ramps, park entrances and track entrances off Bo Peep Road.

With Lake Burrumbeet likely to be closed for some weeks, lake users are encouraged to make use of Lake Learmonth, and Lake Wendouree, both of which remain open to the public.

Blue-green algae can result in taste and odour issues in water supplies.

Some species of blue-green algae produce toxins that are harmful to humans and animals when they are consumed, inhaled or contact the skin.

Higher than normal temperatures and high ph readings in the water can contribute to the problem.

In dry periods low water storage levels and low water inflows can also create similar problems.