Hydroelectricity

What are some disadvantages of hydroelectricity?

Hydroelectric plants can damage the aquatic ecosystems up and downstream. It has been shown that plants along the Nroth Atlantic and Pacific coasts of North America have contributed to a decrease in the population of native salmon.

The reservoirs of some plants may produce large amounts of methane and carbon dioxide, due to decomposing plant materials on the lake floor.

Dam failures can lead to large-scale catastophes.