Question

mention three disadvantages of producing hydroelectricity by constructing the dams

Answer 1

Hydropower offers advantages over other energy sources but faces unique environmental challenges. Hydropower is a fueled by water, so it's a clean fuel source. Hydropower doesn't pollute the air like power plants that burn fossil fuels, such as coal or natural gas.

Answer 2

Disadvantages:

A vast variety of flora and fauna (plants and animals) get affected.

Dams can be constructed only at a limited number of places.

it creates sedimentation of rocky sand particles thereby  creating poor sedimentation which leads to the decline of fishes reproduction