In a statement published on Monday, the government said that the staff at List research centre had detected cynobacteria at the Romwiss beach, close to Baschleiden in the Boulaide district. “The toxins produced by these cyanobacteria can be dangerous to humans, aquatic wildlife, domestic animals and livestock,” it wrote.

Dogs should be prevented from entering the water at this beach and humans are advised not to eat fish caught there.

No ban was introduced on any of the other beaches at the popular bathing lake. At the time of writing there was also no restriction on bathing at the Weiswampach lake or Remerschen ponds.

With summers heating up, blue algae blooms are becoming more frequent at the reservoir, the water from which is treated and used for human consumption in the national network. The water authority said there was no risk related to the consumption of drinking water as the raw water is drawn from a depth of 25 metres where the concentration of cyanobacteria is very low.

The public can monitor the situation by visiting www.waasser.lu.