A phenomenon that is becoming increasingly common during hot, dry summer months: a green film on the surface of the water. This is usually caused by blue-green algae.

However, blue-green algae is actually a misnomer, as these are not algae but cyanobacteria that can develop in slow-flowing or stagnant waters.

They form green streaks or a floating green film.
When the weather remains warm and there is little rainfall, they can temporarily multiply rapidly, resulting in what is known as a "blue-green algae bloom."

Blue-green algae can irritate the skin, mucous membranes, or eyes upon direct contact.

Therefore: Please take care of your health. Avoid contact with the water.

The good news is that as temperatures drop and rainfall increases, the concentration of blue-green algae will decrease again.

Why are we pointing this out? Quite simply: blue-green algae can also form on our rainwater retention basins.

And since there are one or more rainwater retention basins in every urban area, which are not always recognizable as such but are often mistaken for natural lakes due to their natural design, it is important to us to inform you about the phenomenon of blue-green algae.

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