The chickens had been playing with it and it caused a nipple to be on the drip position long enough to empty 5 gallons of water onto the sand under it.

Yes, a heated coop in an arid climate would make drying out soaked sand, and using sand in the first place, a much more viable proposition....as well as the frequency of 'cleaning up' that you employ @azygous .I did not need to shovel and haul the wet sand out. I merely stirred it up, aerated it so it could air dry. It was dry in two days in spite of the freezing cold. It did not freeze solid because my enclosed run stays ten degrees warmer than outside and the chickens kept it stirred up since they love digging in damp sand.