I think I'm probably being overcautious but, I'm fine with that.
3 extra feet of water doesn't do much for my fishery - now is also sorta in the middle of spawning for 2 or 3 of my species so, it might not be good to go messing with water levels right now.
However, given my topography of the whole area around the pond, adding 3 feet of water would add almost an acre of surface area to my pond. The thing is, it would mostly be unusable surface area because it would mostly just flood areas that have dense bushes and trees. Later in the year, it might actually help with the subsequent spawns and survival of some of my shiners, though. They would have more protected areas.