11-3-7: PERMITS:
   A.   Future Uses: Except as specifically provided in subsection A1, A2 and A3 hereunder, no material change shall be made in the use of land and no structure or tree shall be erected, altered, planted or otherwise established in any zone hereby created unless a permit therefor shall have been applied for and granted. Each application for a permit shall indicate the purpose for which the permit is desired, with sufficient particularity to permit it to be determined whether the resulting use, structure or tree would conform to the regulations herein prescribed. If such determination is in the affirmative, the permit shall be granted.
      1.   In the area lying within the limits of the horizontal zone and the conical zone, no permit shall be required for any tree or structure less than seventy five feet (75') of vertical height above the ground, except when because of terrain, land contour or topographic features such tree or structure would extend above the height limits prescribed for such zone.
      2.   In the area lying within the limits of the approach zones but at a horizontal distance of not less than four thousand two hundred feet (4,200') from each end of the runways, no permit shall be required for any tree or structure less than seventy five feet (75') of vertical height above the ground, except when such tree or structure would extend above the height limit prescribed for noninstrument approach zone.
      3.   In the areas lying within the limits of the transition zones beyond the perimeter of the horizontal zone, no permit shall be required for any tree or structure less than seventy five feet (75') of vertical height above the ground except when such tree or structure, because of terrain, land contour or topographic features would extend above the height limit prescribed for such transition zones.
Nothing contained in any of the foregoing exceptions shall be construed as permitting or intending to permit any construction, alteration or growth of any structures or trees in excess of any of the height limits established by this Chapter except as set forth in Section 11-3-4 of this Chapter.
   B.   Existing Uses: No permit shall be granted that would allow the establishment or creation of an airport hazard or permit a nonconforming use, structure or tree to be made or become higher or become a greater hazard to air navigation than it was on the effective date hereof or any amendments thereto or than it is when the application for a permit is made.
Except as indicated, all applications for such permit shall be granted.
   C.   Nonconforming Uses Abandoned Or Destroyed: Whenever the City determines that a nonconforming structure or tree has been abandoned or more than eighty percent (80%) torn down, physically destroyed or decayed, no permit shall be granted that would allow such structure or tree to exceed the applicable height limit or otherwise deviate from the zoning regulations.
   D.   Variances: Any person desiring to erect or increase the height of any structure, or permit the growth of any tree, or use his property, not in accordance with the regulations prescribed in this Chapter, may apply to the Planning and Zoning Commission for a variance from such regulations. Such variances shall be allowed where it is duly found that a literal application or enforcement of the regulations would result in practical difficulty or unnecessary hardship and the relief granted would not be contrary to the public interest but will do substantial justice and be in accordance with the spirit of this Chapter.
   E.   Hazard Marking And Lighting: Any permit or variance granted may, if such action is deemed advisable to effectuate the purpose of this Chapter and be reasonable in the circumstances, be so conditioned as to require the owner of the structure or tree in question to permit the City at its own expense, to install, operate and maintain thereon such markers and lights as may be necessary to indicate to flyers the presence of an airport hazard. (Ord. 475, 1974)