Like John says they are not pools, spas, fountains or any other 680 thing since people don't actually bathe in them and they arent decorative. I doubt you can call them a sink so we are left with 682 by default if we look at the water at all. Assuming this is not at a coast or a flood plane the datum plane thing is moot so we are left with a GCFI needs to be used on outside receptacles. If they drop a tool in the water, the GFCI will trip.
I don't see any equipment in the water so we do not have an equipotential plane situation.
