Rainwater harvesting is the most effective method of water conservation. This is the most useful method for a developing country like India, where there is a huge gap in demand and supply of fresh water while also reducing the cost of transportation and treatment of water for use. The collected water reduces flooding and decreases soil erosion by decreasing the likelihood of run offs during periods of heavy rainfall. This is good for our rivers, streams, oceans and lakes, as they will be less polluted over time. It is important to conquer the deficiency of surface water to meet our demands. To capture decline in the ground water levels. To improve the accessibility of ground water at particular place and time and use rain water for supportable advancement. To build invasion of rain water in the subsoil this has diminished radically in urban regions because of the clearing of open zone.