If any of the City taxes on real property on the City tax roll remain unpaid on March 1 next following the date when the roll was received by the Treasurer, then it shall be the duty of the City Treasurer to return all such unpaid taxes on real property to the County Treasurer in the same manner as returns made by township treasurers of State and County taxes. These returns shall be made on a delinquent tax roll which the City Treasurer shall make in duplicate. This roll shall include all the additional charges previously provided by this Charter. The additional charges on the roll shall be added to the amount assessed against each description in the roll. The taxes thus returned shall be collected in the same manner as other taxes returned to the County Treasurer are collected under the provisions of the general tax laws of the State, and the same rate of interest and all charges shall be collected upon that real property, and all taxes upon real property so returned as delinquent shall be and remain a lien upon that real property until paid. The City Treasurer shall retain the copy of the delinquent tax roll in the files of the City.