Blue-green algae can sometimes build up in our reservoirs, particularly during warmer months. These algal blooms are a natural phenomenon, caused by a rapid increase in the population of algae.

Although algal blooms aren't always harmful, some can be toxic and so all visitors to the reservoir are strongly advised to avoid contact with the water and to prevent animals drinking from it.

The algae itself is removed during the water treatment process and does not, therefore, represent a danger to the drinking water in supply.

Image of algal bloom in water