[RedDevil]

I've been in the Eifel last summer, close to a large(ish) lake created by a dam.
However, large dams and lakes are pretty much the exception there. The Rur river is dammed every few kilometers downstream with just a few meters drop each time.

It is way cheaper to build a string of tiny dams than to build one big one, while the same amount of water flows over the same drop height. The river remains a river, more or less, and the land loss is minimal. The large lake upstream helps by regulating the flow to negate changes in the weather, so all dams can produce electricity fairly constantly.