The charge for fifty thousand gallons per month shall be the maximum charge for water consumed and returned to the sanitary sewer system by residential users, public schools and the courthouse; all such water received from residential users, public schools and the courthouse in excess of fifty thousand gallons per month shall be received without charge; and, upon satisfactory showing by a commercial user that the water consumed by the user in excess of fifty thousand gallons per month does not reach the sanitary sewer system of the city, no fee shall be charged for all such water received in excess of fifty thousand gallons per month and shown to the satisfaction of the city not to reach the sanitary sewer system of the city; provided, however, that no reduction shall be allowed to any commercial user whose water consumption is less than an average of fifty thousand gallons per month. (Ord. 320, 1983: Ord. 3 11 § II, 1982)