Which characteristic is NOT typical of dry barrel hydrants?

Dry barrel hydrants are specifically designed to prevent water from freezing in cold climates. This is achieved through the design where the hydrant remains empty of water when not in use. The presence of a drain hole allows any water that might be residual in the hydrant to drain out, preventing freezing. When a dry barrel hydrant is activated, water flows from the underground supply to the nozzle, and once the nozzle is shut off, the water drains back out, leaving the hydrant dry.

The characteristic of remaining filled with water at all times is not accurate for dry barrel hydrants. This is what distinguishes them from wet barrel hydrants, which do contain water at all times. Therefore, the correct answer highlights the unique design feature of dry barrel hydrants that allows them to function safely in freezing conditions by avoiding the risk of ice formation within the hydrant.