If any person in violation of this chapter permits loose material to fall on or accumulate on public property, he shall immediately abate such condition or shall be deemed to have created a public nuisance. Such a nuisance shall be abated with or without legal action and such other proceedings shall be taken with respect thereto as authorized by law and the ordinances of the city for the prevention, abatement and punishment of nuisances; and it shall be no defense to any prosecution or proceeding under this section that the person violating the same has a franchise to use or occupy such public property. Failure to abate such nuisance which results in action being taken by the city for such abatement shall result in the violator being liable for all expenses incurred by the city in its abatement action. (Ord. 154 §1, 1970; Ord. 152 §3, 1970).