It displace large number of people and inhabitance of flora fauna and many aquatic plants and animals are lost
they donot give adequate facilities to those who are displaced
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The Brainliest Answer!
The construction of large dams completely change the relationship of water and land, destroying the existing ecosystem balance which, in many cases, has taken thousands of years to create. Currently there are around 40,000 large dams which obstruct the world's rivers, completing changing their circulation systems: this is not going to occur without dire environmental impacts. 

Throughout the past few years, the negative impacts of dams have become so well known that most countries have stopped building them altogether and are now forced to invest their money into fixing the problems created by existing dams.
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