A sanitary hydrant comprises an isolated reservoir that can be positioned below a freeze level at the location of installation. A piston within the isolated reservoir is operable to expel, during a downward stroke, stored fluid from the reservoir before actuating a valve that allows fluid to flow from a fluid supply source through the hydrant. On an upward stroke, the piston releases the valve and generates a negative pressure within the reservoir that draws fluid from within the hydrant into the reservoir.