Question: why are some fire hydrants green?
Answer: Green: 1000-1500 GPM, for a 4-story house that's 61 by 61 and 40 ft tall. Blue: 1500 GPM or more, for a 4-story house that's 70 by 70 feet and 40 ft tall. Some colors don't always refer to GPM. Yellow indicates that the water comes from a public supply system.