(A) Regulations not retroactive. The regulations prescribed in this subchapter shall not be construed to require the removal, lowering, or other change or alteration of any structure not conforming to the regulations as the effective date of this subchapter, or otherwise interfere with the continuance of a nonconforming structure. Nothing contained herein shall require any change in the construction, alteration, or intended use of any structure, the construction, alteration of which was granted all necessary and appropriate permits from regulatory authorities and was began prior to the effective date of this subchapter, and is diligently pursued.
(B) Marking and lighting. Notwithstanding the preceding provisions of this section, the owner of any existing nonconforming structure is hereby required to permit the installation, operation and maintenance thereon of such markers and lights as shall be deemed necessary by the Board of Aviation Commissioners to indicate its presence, at the expense of the city.
(Ord. 50-C-90, passed 2-12-91)