When the use of grease, oil and sand traps is required by the UPC or the Bothell standards, whichever is more stringent, such traps shall be installed by the owner or occupant of any property or premises before such property or premises is connected to the public sewers or during any expansion or renovation. Where installed, all grease, oil and sand traps shall be maintained by the owner or occupant, at the user’s expense, in continuously efficient operation at all times. (Ord. 2261 § 9, 2018; Ord. 1634 § 1, 1996).