It shall be the general duty of the 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 this Code or any other ordinances of this City. Whenever, by the provisions of this Chapter, a power is granted to the Traffic Engineer or a duty imposed upon him, the power may be exercised or the duty performed by his deputy or by a person authorized, in writing, by him.