Rooftop rainwater harvesting is the technique through which rainwater is captured from the roof and stored for use later. Harvested rainwater can be stored in sub-surface groundwater reservoirs or in storage tanks.   Advantages of using rooftop rainwater harvesting Provides self-sufficiency to water supply. Reduces the cost of pumping groundwater. Provides high-quality water that is soft and low in minerals. Improves the quality of groundwater through dilution when recharged to the ground. Reduces soil erosion in urban and rural areas. Is a cost-effective and simple technique. RWH structures easy to construct, operate and maintain. In saline or coastal areas rainwater provides good quality water, and when recharged to the ground, it reduces salinity and also helps in maintaining the balance between the fresh-saline water interface. In Islands, due to the limited extent of freshwater aquifers, rainwater harvesting is the most preferred source of water for domestic use. # vadodara, Surat, Ahmedabad