They drink from a zillion places, even the smallest puddle in the woods. If your pond is the only water around and there's deer in the area, they'll be using it...you're just missing the sign. Either way, I wouldn't count on hunting a "Water Source". A quick shower can ruin your hunting plans. Like I say, all they need is a little puddle somewhere. Hunting a water source would only be regular to me in extreme drought...which can end with an overnight shower.