(A)   The City Manager, subject to any directions which the Council may give by motion or resolution, is hereby authorized to have traffic lanes marked upon the roadway or any street where a realignment of traffic is necessary.
   (B)   Where the traffic lanes have been marked, it is unlawful for the operator of any vehicle to fail or refuse to keep the vehicle within the boundaries of any lane, except when lawfully passing another vehicle or preparatory to making a lawful turning movement or otherwise authorized by ordinance.
(`90 Code, § 20-33)