For years I haven't supplemented light in my coops to extend the daylight during winter to promote laying. This year I've decided on doing so. I've always kept food and water out of the coops for lots of reasons, mostly because they aren't needed while the chickens sleep.
In the middle of the night the other night, which is not an uncommon time for me to suddenly get major brain flashes, it occurred to me that the light will wake my chickens and they may need water during those two hours before sunrise. Duh.
So I had a couple sets of vertical type nipples and I found some plastic containers and in minutes, had a waterer for each of the two coops.
The only issue with keeping water inside a coop at night, especially in deep winter, is that if they leak, it will increase the humidity in the coop, presenting the danger of frostbite.
I solved the problem by placing an old, very shallow cake pan under each waterer. The water in the drip pans gets emptied before nightfall, and the bedding, which is sand, stays dry.