Does the collected rain water requires treatment?
Yes, the collected rain water requires treatment even though rain water is not in itself contaminated but as there are many pollutants and impurities present in the atmosphere, such as suspended particulate matter, harmful gases like oxides of nitrogen and sulphur, etc which either react with the rain water or get dissolved in it; therefore treatment of the rain water becomes important. Treatment is all the more necessary as ground water once polluted cannot be treated back.
