Whenever any ordinance of the City designates any one-way street or alley, the City Traffic Engineer shall place and maintain signs giving notice thereof, and no such regulation shall be effective unless such signs are in place. Signs indicating the direction of lawful traffic movement shall be placed at every intersection where movement of traffic in the opposite direction is prohibited.
Upon those streets and parts of streets and in those alleys described and designated by ordinance, vehicular traffic shall move only in the indicated direction when signs indicating the direction of traffic are erected and maintained at every intersection where movement in the opposite direction is prohibited.