No permanent sidewalk or footwalk shall be constructed within the city by any person unless it conforms to the specifications therefor on file in the office of the Mayor of the city; provided, that under special circumstances the Council may, by an order entered of record, specify any change or variation from such specifications. All permanent sidewalks or footwalks built by the city, where the owners have failed to construct them, shall be built in accordance with those specifications; but if any variation is made in the construction of such sidewalks by the city, such variation shall not deprive the city of its right to recover the cost of the construction of the sidewalk, and such variation in the specifications shall be deemed to have been made under the authority of the Council if the sidewalks, after being so constructed, are accepted from the contractor by the Council.
(1991 Code, § 18-16)