Question

Why are dams considered to be good source of conserving and managing water resource?

Answer 1

Precipitation and melt water are irregular in time and quantity. Dams create reservoirs that allow knowledge and predictability of how much is water is available and what rate of usage is practical. In addition, a dam raises the elevation of that stored water, reducing the energy required to distribute it.

Finally, dams can permit some degree of control over water release rates and thereby reduce damage by flooding and erosion.

Of course, there are watersheds that rely on periodic flooding to refresh historical downstream environmental conditions. For some, that is a natural value that should be preserved. Those who are protected from flooding may have other opinion