Question

why there is a need for harvesting rain water

Answer 1

in order to conserve water to prevent lack of water

Answer 2

There is an urgent need of rainwater harvesting against the disadvantages of multipurpose project.Reasons r :
1. It is viable alternativefor both social nd economical nd enviromental.
2. It is carried out to conserve nd store water.
3. It reduces water scarcity.