The period of active reproduction or bloom of cyanobacteria in Luxembourg is from August to October. These unicellular bacteria prefer calm waters rich in nutrients. In the Grand Duchy, these include the Upper-Sûre Lake, the Weiswampach Lakes and the Moselle.
The Luxembourg Institute of Science and Technology (LIST), the Administration de la gestion de l'eau (Water Management Authority), has adapted the Bloomin'Algae mobile tool to collect the latest information on the location of cyanobacteria hotspots. Users of the app can literally send a photo of "blooming" water, a description and a geolocation with a few taps on the screen.
The dangers of cyanobacteria should not be underestimated. They produce dangerous toxins that threaten the health of not only humans, but also domestic animals and pets. For dogs and cats, bacterial poisoning can be fatal if not treated in time.
Last year, the bacteria bloomed early due to heat and drought. Now there are no breeding grounds, so they will not stop the bathing season yet. However, at the slightest threat, it is worth waiting until the beaches are closed, as happened in Remerschen on August 26 last year.