What is rain water harvesting? Write a note on advantages of rain water harvesting?

Rain water harvesting is a process by which we conserve rain water. The rain water is stored for reuse before it goes down the drain and gets wasted. The water which falls on the roof of a house is collected in an underground tank through a rain pipe. From the tank, water is purified and reused. 

This water can be used for irrigating plants, cleaning, washing etc. The conserved water can also be used for the purpose of drinking if the tank used for storing the harvested water is completely cleaned.

Few of the advantages of rain water harvesting are:

1) Rain water harvesting requires very small amount of maintenance. It provides free water which can be used for various purposes at a very low cost.

2) Rain water thus collected can be used for various domestic purposes such as drinking, cooking, bathing, washing, laundry etc.

3) This water can also be used for irrigation and provides regular water supply in drought prone areas.

4) Rainwater harvesting also reduces the risk of flooding of roads in cities as collecting of rainwater reduces excess of water to get wasted.