The city traffic engineer shall install and maintain official traffic signals at those intersections and other places where traffic conditions are such as to require that the flow of traffic be alternately interrupted and released in order to prevent or relieve traffic congestion or to protect life or property from exceptional hazard.
The city traffic engineer shall ascertain and determine the locations where such signals are required by resort to field observations, traffic counts and other traffic information as may be pertinent, and his or her determinations therefrom shall be made in accordance with traffic engineering and safety standards. (Prior code § 25.02.032)