No residential lot may be created by subdivision which will be subject to periodic inundation or overflow from storm drainage or floodwaters. All building construction and other improvements shall conform to the City’s flood ordinance. The City Engineer may require that the top of the curb elevations be designed so as to ensure adequate evacuation of persons by automobile in the event of a 100-year flood. All elevations shall be referenced to the United States Coast and Geodetic Survey or to elevations established by the City Engineer.