Whether RWH helps to get immediate benefits?
Yes. In case roof top rainwater harvesting where the water is collected in storage tanks/sumps after filtering, the water is available for use the moment it rains. In case of ground water recharge where the quality of ground water is poor or moderate considerable improvement in quality would be observed from three to five years, if continuous recharge of rain water is effected into an open well. However, slight improvement can be seen within weeks of rain if RWH structures have been installed. As far as improvement in ground water table is concerned, the improvement can be seen even during one rain fall season if large number of people have done RWH in a locality. In short, rain water is relatively pure form of water and when it is added to the relatively poor quality of ground water, the quality of that water will improve due to dilution. More the water harvested, better will be the result.
