Rainwater harvesting involves the storage rain water, that would otherwise be drained away. In rainwater harvesting, rain water is collected and diverted into percolation tanks. It is stored in them for later use.
This water helps to replenish groundwater reserves. Further, the stored rainwater can be used for washing and cleaning, thus reducing the demand for potable water for these activities. Also, it can be supplied to agricultural fields during times of water scarcity. Hence, it helps to solve the water problem.