All traffic control signs, signals and devices shall conform with the Indiana Manual on Uniform Traffic Control Devices as approved for streets and highways by the Indiana Department of Highways. All signs and signals required under this chapter for a particular purpose shall be so far as practicable be uniform as to type and location throughout the city. In addition, the city traffic engineer may design and erect special signs and markings as required, but not inconsistent with state law, to further the purposes of this chapter. All traffic control devices so erected and not inconsistent with the provisions of state law or this chapter shall be official traffic control devices. (Prior code § 15-26)