Should any area wall become unsafe or insufficient for the proper support of the improvements constructed upon the street, the city manager shall order the same to be forthwith repaired to conform to the provisions of this chapter or other ordinances of the city in relation thereto, or if the person shall fail to so repair the same forthwith, the city manager shall cause the same to be filled up at the cost and expense of the person so permitting the same to be out of repair, and should any person allow any such area wall to remain out of repair for a period of five days after receiving notice to repair the same, he may be fined as hereafter provided.