A method of preventing tampering with a hydrant includes inserting an operating stem of the hydrant through a central bore of an operating nut to mount the operating nut on the operating stem; and rotatably threading a grooved nut onto a threaded distal end of the operating stem, the grooved nut defining an indentation in an outer surface of the grooved nut, wherein: rotatably threading the grooved nut onto the threaded distal end of the operating stem comprises engaging the indentation with a mating groove tool and rotating the grooved nut with the mating groove tool.