We just lost our first chicken this morning, and I think to the same problem (even though there WAS water available...it has been 90+ degrees every day). Either that or coccidosis...it's hard for this first-timer to know.
We nursed her for a few hours last night with electrolyte water (homemade molasses kind), but she was gone by sunrise. Tough loosing your first one! I don't think I'll get used to it.
So glad your dumb chicken recovered ;).
Awe I'm sorry. I think if it was coccidia more chickens would be showing symptoms and you'd be finding suspect poop. I hope it's not.
I'm not sure about the homemade electrolytes... haven't used them myself. But did use baking soda water to rid pasty butt. I'd actually try giving them some baking soda water. 1tsp per gallon.
The rest of the flock is doing perfectly fine, thankfully, which is why I suspect stupidity-dehydration. The one that died was always small, picked-on, and somewhat unsure-seeming.
What signifies the coccidia poop? I've read through lists of symptoms multiple times, but not heard as much about the actual characteristics of the poop.