Hi Sean...
I knew the chap but did not see the accident.
The pilot was landing his bugsmasher on floats, it was not amphibious to fuel up we think.
The bugsmasher (think it was a cub but not sure now) dipped a wing flipping the aircraft.
The pilot was knocked unconscious and drowned when the aircraft sank.
There were no boats nearby, that was quite a few years ago now.
Cheers...Happy Landings...Doug