Editing Water turbine (section)

== Environmental impact ==
{{Main|Environmental impacts of reservoirs}}
[[File:Central hidroeléctrica de Walchensee, Kochel, Baviera, Alemania, 2014-03-22, DD 04.JPG|thumb|[[Walchensee Hydroelectric Power Station]] in [[Bavaria]], Germany, has been in operation since 1924]]
Water turbines are generally considered a clean power producer, as the turbine causes essentially no change to the water. They use a renewable energy source and are designed to operate for decades. They produce significant amounts of the world's electrical supply.

Negative consequences of water turbines are mostly associated with the dams normally required for their operation.  Dams alter the natural ecology of rivers, potentially killing fish, stopping [[Fish migration|migrations]], and disrupting livelihoods. Dams also cause less obvious, but potentially serious, consequences, including increased evaporation of water (especially in arid regions), {{clarification needed span|text=buildup of [[silt]] behind the dam,|reason=How is silt buildup a serious environmental consequence of dam construction?|date=April 2024}} and changes to water temperature and flow patterns. In the [[United States]], it is now illegal to block the migration of fish, so [[fish ladder]]s for species such as [[salmon]] and [[white sturgeon]] must be provided by dam builders.{{cn|date=April 2024}}