I am confused when hearing people talking about duck impoundments. I hear people talking about building duck impoundments for duck refuges, etc and then i hear about people buying/leasing them to hunt. Can someone help me understand what the difference is?

An impoundment is going to be man made structure. It will have levees built or it will be dug out to hold water. examples; flooded corn field, rice fields with potholes, reservoirs, flooded timber, moist soil units. All examples of waterfowl impoundments.