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D.C. fire officials are reporting that two of the closest hydrants to the Georgetown branch library were out of service when the majestic building went up in flames yesterday, ruining collections of precious and irreplaceable material. It’s not clear at this point if firefighters could have put out the blaze more quickly with a full complement of hydrants. But one thing is for sure: Dry hydrants are not a secret among those whose job it is to rush to fires.

Last September, we did a story about the phenomenon. The piece discussed a fire in a Northeast rowhouse that was surrounded by dead hydrants.

From the story: [A]s Lt. L.A. Matthews of Engine 21 in Adams Morgan says, “Even one [inoperable hydrant] is too many, especially if it’s in front of my house.”

Matthews says that some old-timers at the department have so little faith in the reliability of the city’s fire hydrants that they keep mental maps of swimming pools in their service areas to tap in case a hydrant fails. In addition to providing peace of mind, proximity to fire hydrants has financial benefits. Insurance companies typically vary their rates depending on the home’s distance from a hydrant.