Are hydroelectric dams good

Answer 1

It depends on how you look at it. While they provide us with a clean way of producing electricity, the water they dump back has too many minerals that erode the soil on the river banks too quickly. Also, It makes it very hard for fish to navigate around the dam and it can destroy wildlife as well.

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The returned water may cause erosion if it is not handled properly, but NOT by "minerals". The water already holds dissolved salts, and the hydroelectric plant has no effect on them. Any erosion is due to the flow from the power-station outlets being allowed to impinge on the river-bed or banks. Normally it is directed so it will do no harm.

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The obstruction to fish is a genuine problem, and many dams and weirs now have special "fish ladders" that allow migrating fish to pass upstream by swimming up a series of small cascades in a sloping channel shaped like a staircase with a pool on each tread.