How nice to have a nearby river with a long enough stretch of clarity and depth - 5' or more? I suppose one could do similar with some quiet stretches of the Contoocook or Merrimack Rivers - but the latter, at least, is bigger and not particularly clear (or not clear at all).
I don't like "dark waters" - never have:-).
Yes, it is nice! The Lamprey water is not clear, rather murky. I could just barely see the bottom today with goggles (mid-day sun). I try not to touch bottom if I can - who knows what's there? The river does feel much cleaner though than the ponds especially after a stretch of heat and no rain. There are no algae blooms.