A dam is a barrier that impounds water or underground streams.
Dams generally serve the primary purpose of retaining water, while other structures such as floodgates or levees (also known as dikes) are used to manage or prevent water flow into specific land regions. Hydropower and pumped-storage hydroelectricity are often used in conjunction with dams to generate electricity. A dam can also be used to collect water or for storage of water which can be evenly distributed between locations.
The state-wise list of dams and reservoirs in India.It also includes lakes. Nearly 3200 major / medium dams and barrages had been constructed in India by the year 2012.