The waterworks on Lake Constance are fighting against an invasive mussel species that is spreading rapidly. The quagga mussel, which is up to four centimeters long, is not a problem for drinking water quality, but it gets stuck in pipes and filter systems, explained a spokeswoman for the Lake Constance water supply.

With special filters, larger pipes and new cleaning methods, the water suppliers around Lake Constance are taking up the fight against the intruder that was introduced from the Black Sea region around ten years ago.

According to a study by the University of Konstanz, the invasive mussel could cause millions of dollars in damage. She has also already arrived at Lake Geneva and Lake Biel. Lake Zurich, on the other hand, is still free of it. Flyers inform boat owners around Zurich to clean their boats before using them in Lake Zurich to avoid bringing in the mussel. According to one of the study authors, the spread can no longer be stopped in areas that have already been infected.

The US lake is made up of 90 percent mussels

According to the study, the quagga mussel mass per square meter in Lake Constance, Lake Geneva and Lake Biel is expected to increase nine to twenty-fold over the next two decades, caused primarily by greater population in the deeper areas of the lakes. This could lead to major changes in the ecosystem.

The Lake Constance water supply estimates that Lake Constance is about 15 years away from the situation at Lake Michigan in the US. There the mussel has spread so much that it now represents 90 percent of the biomass.