Those are sound points. I can add that the neighbor across the street has a one acre pond that he claims is only fed by a spring. He told me in the 30 years he's lived there(pond was existing) he's only had the pond level drop one foot in the worst of droughts. When I hear something like that it makes me wonder if the existence of a spring is really a concern or it could be a benefit. His pond is at an elevation of about 20 feet above where mine would be. This area supposedly has a large aquifer under it. There's a water bottling plant not far away that supposedly is here because of this aquifer.

Spring or no spring I had intended to have a sealed bottom pond. Relying on a spring to keep a pond full seems like a gamble and I'm not much into gambling when the stakes are high.