Current values of the water balance components, water consumption and water use for Switzerland (a: Hubacher & Schädler, 2010, b: FOEN 2012, c: Sinreich et al 2012, d: Freiburg House, 2009, e: SDC & WWF 2012, f: calculated from BFE 2012, g: data from nuclear power plant operators). 1 km3 = 1 billion m3. 41 km3 corresponds to a layer of water about 1 m deep over the surface of Switzerland (41.285 km2). To illustrate the magnitude of the reservoir: The water content of Swiss lakes (130 km3, considering only the Swiss portion) corresponds to a 3 m deep layer of water spread over the entire area of Switzerland, or more than 2 years’ worth of precipitation. The overall water balance of Switzerland is clearly illustrated here.