Water is, after oxygen, the most important element without which life would not exist on this planet. Without oxygen one survives a couple of minutes, without water only some days. Although water is abundant only a small part is potable. Still it is wasted as though there is no tomorrow. While the world population will grow in the next 30-40 years by around 30%, from today 7 billion to 9 billion people the amount of potable water remains...

According to the BBC , 24. March 2010, the south-west of China faces a severe water shortage. Tenth of million of people are affected. Some blame the Climate Change for it. Even if the Climate Change has only a small part to the problem, it is safe to assume that with time the part will become bigger and more wide spread. Another problem is the growing world population. In the middle of this century world population will reach 9 billion...