Although oceans cover about 70 percent of the Earth’s surface, water is nonetheless a scarce commodity – at least freshwater, which represents only three percent of the world’s water resources. And most of that is frozen in the polar ice caps. Compared to the salt water of our planet’s seas – about 1.3 billion cubic kilometers – the roughly 200,000 cubic kilometers of water in the world’s lakes and rivers are like a pathetic trickle. Man has direct access to less than one percent of global water supplies.

As valuable as crude oil
The most abundant freshwater reserves are found in groundwater, but half of it is more than 800 meters underground. More than 50 countries around the world are already experiencing acute water shortages. Some 1 billion people have no access to clean drinking water, while sanitary facilities are an absolute luxury for 2 billion people. Every day, thousands of children die of infections caused by dirty water. And the situation is becoming ever more dire: Environmental pollution, globalization, climate change with the allied threat of a falling water table, and springs that are drying up will make this precious liquid as valuable as oil in the next few decades.

Immense consumption for food production
In Germany, people use about 122 liters of water daily. Only between three and six liters of that are needed for drinking and cooking. Most of the water is used for flushing the toilet, taking a bath or showering. But that's only the “visible” part. Around the world, some 70 percent of water consumed is used for cultivating food or producing everyday products. The British scientist John Anthony Allan investigated these hidden quantities and coined the term “virtual water”. These are amounts of water that are used in the production of goods. Allan determined that every cup of coffee contains 140 liters of virtual water that had been used for the cultivation, processing, packaging and shipping of the beans. According to this calculation model, 2,400 liters of water are needed to produce a hamburger. Projected, a U.S. citizen uses 6,000 liters of water per day and a German citizen about 4,000 liters.

Astonishing facts about the use of “virtual water”:

• 550 liters of water are needed to produce 400 grams of flour.
• 1,000 liters of water are needed to produce one liter of milk.
• Water consumption for the production of one kilogram of…
• Rice: 3,000 liters
• Corn: 900 liters
• Wheat: 1,350 liters
• Beef: 16,000 liters
  
  

(Source: “100 facts and figures on the topic water”, German IHP/HWRP national committee at the Federal Institute of Hydrology, ihp.bafg.de/servlet/is/8397/)