(a) The accumulation or existence upon any premises, lot or parcel of ground of any material of any kind which could or would become offensive to human beings, or detrimental to health, or which by its existence constitutes a rat infestation or conditions conducive to rat infestation, shall constitute a nuisance.

    (b) A "rat infestation" will be deemed to exist upon a showing of the actual presence of rats. Conditions conducive to rat infestation will be deemed to exist when conditions favoring the multiplication or continued existence of rats are present or when conditions providing shelter, protection or food for rats are present, or when there is any evidence indicating the presence of rats.

(Code 1964, § 10.5010)