u/DungeoneeringDave

Before I begin, I should preface that I only have a rudimentary understanding of hydrological structures.

I was watching an episode of Our Planet that brought up the issue of dams causing rivers to reduce and straining the ecology that depends on a consistent flow, which made me wonder:

I understand that these dams are constructed for the express purpose of serving human populations in agriculture, industry and domestic water usage, but can't we design dams that let off enough water to only reduce the flow of the river rather than eliminate it for the sake of ecological health?