It is hereby declared that any junk or junk vehicle located upon private property, unless excluded by Section 51.04, constitutes a threat to the health and safety of the citizens and is a nuisance within the meaning of Section 657.1 of the Code of Iowa. If any junk or junk vehicle is kept upon private property in violation hereof, the owner of or person occupying the property upon which it is located shall be prima facie liable for said violation.
(Code of Iowa, Sec. 364.12[3a])