No outside toilets shall be kept or allowed in the city, except for professionally maintained portable toilet units for which the city has approved a permit. The mayor shall have the authority to issue permits for the placement of professionally maintained portable toilet units at such locations in the city as the mayor deems necessary to avoid unsanitary conditions or practices. Any such permit shall be in writing and shall include the location of the unit, the term of the permit and the name of the person authorized to place and maintain the unit. The person to whom the permit is issued shall maintain the portable toilet unit in a clean and sanitary condition. Permits may not be issued for a term of more than nine (9) months. (Ord. 625, 3-11-2002)