In the recent times, dams have come under great opposition because:
(i) Construction of dams has resulted in problems like excessive sedimentation, water-logging, soil erosion, sudden floods, large scale deforestation, extinction of species, displacement of communities and tribal communities loosing their livelihood. Dams also fragment rivers, making it difficult for aquatic fauna to migrate, especially for spawning.
(ii) Dams that were built to control floods have triggered floods due to sedimentation in the reservoirs. Big dams have been unsuccessful in controlling floods at the time of excessive rainfall. The release of water from the dams during heavy rainfall worsens the situation.
(iii) Dams also cause earthquakes, waterborne diseases and pollution due to excessive use of water.
