(Amended by Ordinance Nos. 138415, 173369, 177028 and 184957, effective November 25, 2011.)  It is unlawful for owners or occupants to permit any tree upon or in front of their premises, to interfere with or come in contact with wires belonging to the City, or to permit the branches of such trees to be less than 7-1/2 feet above the sidewalk, or 11 feet above the roadway; provided, however, that on any street which is designated as a Regional Trafficway, Major City Traffic Street, or a District Collector, or a one-way street, and where parking has been prohibited, limbs of trees shall be trimmed to a height of 14 feet above the crown of the street.  Whenever the Director of the Bureau of Transportation finds that a condition prohibited by this Section exists, the condition is a public nuisance.  In addition to the penal enforcement of this Title, the Commissioner of the department under whom the Office of the Director of the Bureau of Transportation is administered may take steps in accordance with the procedures set forth in Title 29 concerning abatement of nuisances, including assessment of cost of abatement against the property on which or in front of which the tree is located.