section_path: Rivers and lakes
section_name: Rivers and lakes
paragraph_text: Rivers and lakes
  
  The Alps provide lowland Europe with drinking water, irrigation, and hydroelectric power. Although the area is only about 11% of the surface area of Europe, the Alps provide up to 90% of water to lowland Europe, particularly to arid areas and during the summer months. Cities such as Milan depend on 80% of water from Alpine runoff. Water from the rivers is used in at least 550 hydroelectricity power plants, considering only those producing at least 10MW of electricity.
  
  Major European rivers flow from the Alps, such as the Rhine, the Rhône, the Inn, and the Po, all of which have headwaters in the Alps and flow into neighbouring countries, finally emptying into the North Sea, the Mediterranean Sea, the Adriatic Sea and the Black Sea. Other rivers such as the Danube have major tributaries flowing into them that originate in the Alps.
  
  The Rhône is second to the Nile as a freshwater source to the Mediterranean Sea; the river begins as glacial meltwater, flows into Lake Geneva, and from there to France where one of its uses is to cool nuclear power plants. The Rhine originates in a 30 km (12 sq mi) area in Switzerland and represents almost 60% of water exported from the country. Tributary valleys, some of which are complicated, channel water to the main valleys which can experience flooding during the snowmelt season when rapid runoff causes debris torrents and swollen rivers.
  
  The rivers form lakes, such as Lake Geneva, a crescent-shaped lake crossing the Swiss border with Lausanne on the Swiss side and the town of Evian-les-Bains on the French side. In Germany, the medieval St. Bartholomew's chapel was built on the south side of the Königssee, accessible only by boat or by climbing over the abutting peaks.
  
  Additionally, the Alps have led to the creation of large lakes in Italy. For instance, the Sarca, the primary inflow of Lake Garda, originates in the Italian Alps. The Italian Lakes are a popular tourist destination since the Roman Era for their mild climate.
  
  Scientists have been studying the impact of climate change and water use. For example, each year more water is diverted from rivers for snowmaking in the ski resorts, the effect of which is yet unknown. Furthermore, the decrease of glaciated areas combined with a succession of winters with lower-than-expected precipitation may have a future impact on the rivers in the Alps as well as an effect on the water availability to the lowlands.