Lake Constance

The size of Lake Constance

The shoreline of Lake Constance is 273 kilometers long, 173 kilometers in Germany, 72 kilometers in Switzerland and 28 kilometers in Austria. The surface area is 535 km². In Middle Europe, only Lake Balaton (594 km²) and Lake Geneva (582 km²) are bigger. From Bodman-Ludwigshafen to Bregenz the lake is 63,5 kilometers long. Because of the curvature of the earth, you can't see Bregenz (Austria) from Constance, even when there is a fabulous sight of the Alps. Because of its impressive size Lake Constance also is called "Swabian Sea", altough the town of Constance is not part of Swabia, but of Baden.

"Überlinger See", a part of the lake

Lake Constance and the Rhine

The Rhine flows through Lake Constance. Only 40 kilometers south of Constance, in Schaffhausen, Switzerland, the biggest waterfall of Europe is situated (the biggest, regarding the water flowing through, the Dettifoss-waterfall in Iceland ist twice as high). This natural barrier has a very good side effect for Lake Constance: There is hardly any shipping of goods on Lake Constance.

Formation of Lake Constance

The Lake Constance of today was shaped at the end of the last ice age, about 15.000 years ago. Because of sedimentation the surface area has halved since then. Even today the lake is becoming smaller (at a slow pace) by sediments which the Rhine brings into the lake.

Grey herons, the lake, the Alps

The quality of the water of Lake Constance

About 4 million persons get their drinking-water from Lake Constance. And today the quality of the water is good. But it wasn't always so. In the 1970s there were problems with to many algae. Fertilization in agriculture and a lack of water purification plants were the reasons for the polluted water. 1972 the federal German government classified Lake Constance as "strongly polluted". Then, in the 1970s purification plants were built. 1981 the German parliament introduced limits on phosphate in detergents. Since the 1980s the quality of Lake Constance's water steadily improved and is quite good today.

Effects of climate change on Lake Constance

Scientists of the university of Constance have found out, that there was a lack of oxygen in deep areas of the lake in the warm winters of 2006 /2007 and 2007/2008. If there was a combination of polluted water like in the 1970s and today's climate, there probably wouldn't be life in the lake any more. There are more problems now with high and low water levels because of climate change.