PEOPLE and pets are being urged to stay out of the water of a mid Wales reservoir following the discovery of blue-green algae.

Natural Resources Wales says it has confirmed the presence of the algae in Llyn Clywedog near Llanidloes and people and pets are being advised not to enter the water.

The algae produce toxins which can cause skin rashes, nausea, vomiting, stomach pains, fever and headache if swallowed. Occasionally it can cause more serious illness such as adverse effects on the liver and nervous system.

The blue-green algae (cyanobacteria) occur naturally in inland waters, estuaries and seas and cannot be removed or treated. They thrive in warm conditions and are likely to come and go throughout the summer season.

Natural Resources Wales say it has contacted the landowner and asked them to put up warning signs around the lake as a result.

Powys County Council has also issued advice.

It says, given the potential health risks caused by blue-green algae people are advised not to swim in the water or to become immersed; not to swallow the water; not to eat fish caught in Llyn Clywedog and not to allow pets or livestock to come into contact with the water

Anyone who has come into contact with water containing blue-green algae should shower with fresh water immediately.

Anyone who has come into contact with affected water and has become ill should obtain medical attention.

For further help and advice please contact Powys County Council’s Environmental Health Team on 01597 827467.