Traffic controls for utility construction and maintenance operations shall conform with OSHA Standards and the Manual on Uniform Traffic Control Devices for Streets and Highways. All construction and maintenance operations should be planned with full regard to safety and keeping traffic interference to an absolute minimum. On arterial streets or streets within the Downtown Business District, as defined by the Zoning Ordinance, construction or maintenance operations interfering with traffic shall need to be coordinated with the City Engineer in order to establish working hours.