If you spend some time observing bees suck up water you should notice that they like dry feet. Their feet. A water hose with a slightly leaking nozzle on concrete is a good bee waterer. The bees land in dry spots around the damp/wet area and tank up. I do have 5 gallon buckets of water with a foam float that I place at hives not near the water hose. The sand idea sounds good.
They, the queen court, take care of the queen's every need and desire. Since the colony contains no jesters I fill in, on a part time basis of course. After all, I want dem bees aworking and not alaffin' all da time