"It may be grandfathered in..... repairing existing dam ?"
EXACTLY! That's why I mentioned that if you pull up any current website map (aside from Google Earth Satellite), the lake is shown to still be there!
Also a correction. My Uncle just told me that the dam was built in 1948-50, and never actually busted. Water was seeping AROUND the edge that was formed into the side of that sandy/sedimentary rock, so my Great Uncle busted the dam and drained the lake before it had a chance to cause any unforeseen damage of the land around the dam. That was in 1970.
