What happens to the water after having been used in our homes or in industrial production processes? The hidden world of
wastewater begins in drains and
sewers, in a labyrinth of underground pipes and tunnels which lead to the
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where, after a series of treatments, step by step, it becomes clean enough to be discharged into rivers, lakes or the sea without harming the environment.
And so where does this wastewater go, starting from the drains in your house, to reaching the point where it will be, once again, pure and clean? Identify the right path in the
labyrinth and then read the letters you find: they will give you the name of the mysterious object!
