When people make dams for their use, they harm the earth in many ways. While making the dam a big place area is required and because of that many trees which are in that area are cut down. This leads to a shortage of trees and because of that environmental pollution increases. While making the dam the equilibrium in the surface area of the earth is imbalanced. A lot of people from that area need to be replaced. They are shifted to other places which make their life tough.