Water Purifies Itself Continuously

When rain falls and before it comes into contact with any aerial pollution the water created from condensed vapour is pure. This water then falls upon the land and becomes contaminated with fertilisers and other materials.
The water then flows into rivers and streams or sinks through the soil to be stored underground.
However when water is evaporated the impurities are left behind (as though the water had been distilled) and the resulting water vapour starts the cycle all over again.
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