How much water is on earth?
The awareness that water is a scarce and extremely valuable resource is the first step and perhaps the most important to achieve a sustainable use of water. If society is awareness the rest will come naturally.
How much water do we use?
A simple question like, «how much water per month do we use?» is enough to bring out that we are not aware of the volume of water we use and how much water we could save if we took certain measurements. Other problems are even less visible to society, such as reduced water quality caused by our consumption and altering the natural water cycle that occurs in intervening in nature.
Just being aware of the problem, we can start looking for solutions.
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