face,
couple comments from el dorado.
chances are the tree wont make it either because of saturated soil failure or drowned roots (insufficient oxygen exchange in saturated soil) in either case as theo says, you'll have a nice big BG condo when it falls in.
another factor, is the pond exposed to much wind? erosion even in clay is possible along the shoreline, an undercut can develop, and eventually the tree comes down.
on the other hand, the tree could last many years before suffering. doug firs have a pretty good tap root (similar to a ponderosa) but they do prefer well drained soil conditions and an intact drip line for shallow root feeding and oxygen exchange.
good luck
