Undoubtedly, hydropower, one of the major sources of renewable energy production, has been a boon of  advancement in technology. But with it also  come two of the most pressing global environmental challenges of modern society i.e.accelerated biodiversity loss and climate change. Such huge projects like the" Three Gorge Dam" of china even have the ability to slow down the earth's revolution time which increase the length of day by only 0.06 microseconds and make the Earth only very slightly more round in the middle and flat on the top.It would shift the pole position by about 0.8 inch. 

Dam construction has played significant roles in flood control, irrigation, navigation, and energy supply; however, the enormous negative effects, such as landslides, ecological problems, siltation, reservoir triggered seismicity ,and water quality decline, could surpass positive gains.