(This would work for pets also.) homemade chicken waterer- so stinking simple and smart! (Wonder if you could do the same thing with a large "Gatorade" cooler and give your hens cool water in the summer.
This non-motorized design uses the chickens’ own weight and a counterbalanced bucket of sand or earth to open and close the door. “The door system is not prone to electrical outages and it automatically self-adjusts for Daylight Savings Time,”