Patent ID: 7520294

Claim:
A water security system for protecting a water supply from contamination being inserted into a fire hydrant, the water security system comprising: a hydrant shoe defining a cavity having a longitudinal axis, wherein the cavity is in fluid communication with the water supply and the fire hydrant; and a backflow prevention assembly positioned in the hydrant shoe, the back flow prevention assembly comprising: a seat positioned in the cavity at an angle with respect to the longitudinal axis of the hydrant shoe, wherein said seat defines an aperture; and a flapper device configured to cooperate with the seat such that the flapper device is spaced apart from the seat in response to the flow of water from the water supply to the hydrant and further configured to contact the seat in response to the flow of water from the hydrant to the water supply to prevent contamination from entering the water supply from the fire hydrant, and wherein the flapper device includes a disc portion defining a plane, a short arm portion oriented at an angle relative to the plane and a resilient portion intermediate the disc portion and the short arm portion.