It is unlawful for any person or persons to consume any alcoholic beverage or possess any open container containing any alcoholic beverage in or about any swimming pool premises maintained and operated by the city as a swimming pool, and in or about any youth sports/recreation field and bleacher section adjacent to such youth sports/recreation field, and in or about any playground area of any park or recreation area maintained by the city. The city parks and recreation director shall cause to be posted appropriate warning signs in all such areas in which the consumption of alcoholic beverages, or the possession of any open container containing alcoholic beverages, is prohibited by this section and section 15-28. (Ord. No. 1231, § 5 (part).)