[R.O. 2004 § 330.010]
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.
[R.O. 2004 § 330.020]
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.
[R.O. 2004 § 330.030]
A. 
The City Traffic Engineer is hereby authorized to determine and designate streets, parts of streets or specific lanes thereon upon which vehicular traffic shall proceed in one (1) direction during one (1) period and the opposite direction during another period of the day and shall place and maintain appropriate markings, signs, barriers or other devices to give notice thereof. The City Traffic Engineer may erect signs temporarily designating lanes to be used by traffic moving in a particular direction, regardless of the center line of the roadway.
B. 
It shall be unlawful for any person to operate any vehicle in violation of such markings, signs, barriers or other devices so placed in accordance with this Section.