I live in NY area and I do not put water in the coop, just the pen. My coop is rather small and is really only used by the hens for the nesting boxes and by all to sleep.
It's been my experience that when chooks are roosting, they are sleeping and they rarely move around, let alone eat or drink.
It would certainly not be a problem to put a waterer in the coop to be on the safe side, however, I'd suggest placing it where it would be less likely to get knocked around and spilled.
All the best with your coop design and building!