Patent attributes
A water hydrant for suppling potable water from a water source has an internal movable riser contained within a housing that extends beneath the ground to a depth below which freezing temperatures cannot reach. A chamber housing located at a distal end of the hydrant, beneath the frost line, contains a valve which may be actuated by the moving riser to provide a flow of water from the water source and through the riser. The chamber housing is configured to receive residual water from the riser when the flow of water has been shut off by the valve and to store the water beneath the frost line under sanitary conditions. A piston is disposed on a distal end of the riser, is slidably disposed within the chamber housing, and moves with the riser to expel water from the chamber housing when a handle of the hydrant is subsequently moved to reopen the valve.