The design, construction and financing of all required sidewalks, curbs, gutters, pavements, sanitary sewers, storm sewers, water mains, fire hydrants, drainage structures and monuments shall be the responsibility of the subdivider and shall conform to public improvement standards established by the city engineer and approved by the city council; provided, however, that the subdivider may meet such requirements by participation in an improvement district approved by the city. (Prior Code § 18A-20)