It is unlawful to create, perform or maintain a public nuisance on public or private properly within the city. A public nuisance consists of knowingly creating, performing or maintaining anything affecting any number of citizens without lawful authority which is either: (1) injurious to public health, safety, morals or welfare; or (2) interferes with the exercise and enjoyment of public rights, including the right to use public property. (Prior code § 7-2-13)