Caused by climate change and the early melting of snow in the Alps, Lake Constance currently has a very low water level.
According to the Baden-Württemberg State Institute for the Environment (LUBW), the large inland lake currently has a level 90 centimeters lower than would be usual for the time of year.
Such a low water level is more typical for the climatic conditions in October.
At the same time, the surface water in the middle of the lake is a few degrees warmer than usual at 24.2 degrees.
"The warming of the water in Lake Constance is a directly measurable consequence of climate change," said Ulrich Maurer, President of the LUBW, on Thursday during a visit to the Institute for Lake Research in Langenargen.
In the marinas in Friedrichshafen or Langenargen, many boat owners are already forced to “unwater” their boats and bring them ashore.
This usually doesn't happen until October.
About a third of the boats cannot stay at their berths because of the low water levels.
80 percent of streams and rivers in the south-west also have water levels below the lowest levels in recent years.
Both small and medium-sized watercourses in the country and large rivers such as the Neckar, Danube and Upper Rhine are affected.
In the vicinity of Constance, the water level was 321 centimeters on Thursday; the last time the water level was lower there was on August 4, 2006. In some places on Lake Constance, floating green carpets of algae are forming;
they grow where the water warms up a lot and it contains a lot of nutrients.
One section of the bank that shows this consequence of climate change is the Schussen estuary at Langenargen.