It shall be the general duty of the city traffic engineer to determine the installation and proper timing and maintenance of traffic-control devices and signals, to conduct engineering analyses of traffic accidents and to devise remedial measures, to conduct engineering and traffic investigations of traffic conditions and to cooperate with other city officials in the development of ways and means to improve traffic conditions, and to carry out the additional powers and duties imposed by ordinances of this city. Whenever, by the provisions of this title a power is granted to the city traffic engineer or a duty imposed upon him or her, the power may be exercised or the duty performed by his or her deputy or by a person authorized in writing by him or her. (Ord. 432 § 2(part), 1982).