Pumped storage is a bit different than an ordinary reservoir with a dam, though. You have more opportunity to build it in a place where it's less likely to caus

Pumped storage is a bit different than an ordinary reservoir with a dam, though. You have more opportunity to build it in a place where it's less likely to cause harm is something goes wrong. It has been used pretty effectively on both sides of the border near Niagara Falls for 60+ years. It's not perfect, of course. Accidents still happen, for example: https://en.wikipedia.org/wiki/Taum_Sauk_Hydroelectric_Power_Station#2005_upper_reservoir_failure https://en.wikipedia.org/wiki/Taum_Sauk_Hydroelectric_Power_... although fortunately nobody was killed.