I have a dock project that I've convinced the client would be so much better timber framed than built with Pressure Treated lumber. I'm back and forth on using white oak (Somewhat local to NH) or red or yellow cedar which is lighter and maybe better suited to sitting over open water (not actually in contact with it) anyone have any thoughts about appropriateness. I think I would use 1x4 cedar or Trex composite for decking, and of course steel posts to support it over the pond. Another advantage/selling point of this dock system is that the all wood connections and dovetailing could make it easy to disassemble and remove in the fall. The decking could built in sections on rails to make it somewhat modular.