Water is a substance that was among the first discovered and abundantly used by the man. Although it is well studied from both, a scientific and a philosophical point of view, its new characteristics and features are still being discovered. Thanks to the development of the science of water, man learned that there are different types of water by its origin, use, characteristics and content of other substances in it. The term „green“ and „blue“ water was introduced into the scientific literature by Swedish ecohydrologist Malin Falkenkamp from the Water Institute (SIWI) in Stockholm. Although this term has been used in the world for years, it has remained closed in the narrow circles of scientific specialists. The term is used especially at the level of consideration of global problems of water and land management and the problem of water crisis that threatens the world. In addition to our daily use of water, water is probably a natural resource that the ordinary world understands the least, so it is rightly considered that this resource is not sufficiently understood even by the engineering educated world. Not without reason, Einstein warned: „There is more perfection in an ordinary drop of water than in all the machines that people have invented.“ Green Water has neither managers nor hosts who care about sustainability and its more rational management, unlike managers and government agencies that care about blue water.
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