Water is not only a place where life began on Earth, but has always been a key element in the survival of civilizations. Even in ancient times in ancient Egypt and Mesopotamia as the homeland of the Incas, the man realized the great importance of water and inhabited in its immediate vicinity. Oldest known wells come from Mesopotamia, around 4000 BC, and the first water system was built in Jerusalem during Solomon, about 1000 years BC. In ancient Rome water sewer system was well developed. Water since time immemorial considered a sacred liquid was a symbol of purification and general engine.
The total amount of water on Earth, including groundwater and water vapor in the atmosphere is estimated at 160 million cubic kilometers. One cubic kilometer contains billion cubic meters respectively trillion liters! But despite the abundance of water on our "blue" planet to satisfy their biological and technological needs of man it is available only a very small part. In fact, 97% of the water is in the oceans and seas salt, 2% is frozen in polar ice caps and glaciers, and in the form of accessible, fresh water there is about 1.5 million billion cubic meters in streams and groundwater water. Scientists aggressively emphasize that the lack of usable water can become a limiting factor of life and production. In many world cities only bottled water is drunk. Today the question is: how will the future provide enough quality water to humans, animals and plants?