Water is a natural element essential for animal and plant survival on planet Earth . We know that with each passing year it is becoming increasingly scarce, both due to global warming caused by the emission of polluting gases emitted by human beings, and by the pollution of drinking water with urban sewage.
In the history of humanity, rivers played an elementary role in the emergence of the first civilizations:they were used to transport people and goods; and played an important role in the survival of various peoples, primarily supplying civilizations with fish and drinking water and later with the development of agriculture .
The civilizations of so-called Eastern Antiquity , mainly Mesopotamia and Ancient Egypt , knew how to use the floods or floods of the rivers Tigers and Euphrates (Mesopotamia) and the Nile River (Egypt) to fertilize the lands. In this way, the land was fertile for the practice of agriculture. In addition, they developed the construction of dams (to accumulate water from rivers during the dry season, in order to irrigate crops) and dykes (to prevent river flooding from destroying these crops).
It is important to note that the territories in which Mesopotamia and Ancient Egypt were found were arid regions with few conditions for survival , therefore the waters of the rivers were fundamental for the development of these civilizations .
Today, after several centuries, water remains essential for the maintenance of life in the world. However, drinking water is a finite natural resource , that is, that it will have an end. Today, 2.5% of all water in the world is potable and 97.5% is salt water (which we do not use for consumption).
Of this percentage of fresh water quoted above (2.5%), only 0.3% represents water from rivers and lakes , the remainder (2.2%) of drinking water is found in groundwater and glaciers . Thus, of all the water in the world, only a small part is available for human consumption.
So what are the factors that are contributing to making the small amount of fresh water that exists in the world even more scarce for consumption? Answering the question, there are several factors that contribute to this alarming state, such as pollution , the urbanization and industrialization . In other words, sewage and waste thrown into rivers due to urbanization and industrialization and the waste of water by the populations of cities are contributing considerably to the scarcity of drinking water in the world.
Currently, reversing this process of pollution and scarcity of drinking water is one of society's greatest challenges. We need to avoid a global water supply crisis for both present and future generations. For this, the public power must initiate an awareness and education program for the maintenance of potable water in the world.
By Leandro Carvalho