Electrolysis at work, baby! Look at that neutral.
I'm still amazed that nothing tripped, that water would have needed an impedence of better than sixteen ohms to avoid tripping out a 15A breaker on a leg-to-leg fault. Given all the contaminants that I'm sure were floating around in it, I'm amazed it was that resistive.
Maybe the water itself kept the breakers from operating? The cooling would mess up the thermal characteristics and the water itself would foul the mechanism?
On a side note, can you imagine coming home and opening your basement door to find water lapping at the top step? That must've been horrifying.
-John
