A. Future Uses:
1. Except as specifically provided in subsections A1a and A1b of this section, no material change shall be made in the use of the 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.
a. In the area lying within the limits of the horizontal zone and the conical zone but not within the limits of an approach zone or transition zone, no permit shall be required for any tree or structure less than one hundred forty feet (140') 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.
b. In the areas lying within the limits of the approach zone but at a horizontal distance of not less than one thousand two hundred feet (1,200') from each end of the runways, no permit shall be required for any tree or structure less than thirty feet (30') of vertical height above the established airport elevation, except when such tree or structure would extend above the height limit prescribed for such instrument or noninstrument approach zone.
2. Nothing contained in any of the foregoing exceptions shall be construed as permitting or intending to permit any construction, alteration or growth of any structure or tree in excess of any of the height limits established by these regulations except as set forth in section 10-1-4 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 of these regulations or any amendments thereto or than it is when the application for a permit is made. Except as indicated, all applications for such a permit shall be granted.
C. Nonconforming Uses Abandoned Or Destroyed: Whenever the city council determines that a nonconforming structure or tree has been abandoned or more than eighty percent (80%) torn down, destroyed, deteriorated 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 these regulations, may apply to the city council, through the airport commission for a variance from such regulations. Such variance 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 these regulations.
E. Hazard Marking And Lighting: Any permit or variance granted may, if such action is deemed advisable to effectuate the purpose of these regulations and be reasonable in the circumstances, be so conditioned as to require the owner of the structure or trees in question at the owner's 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. 912, 10-9-1995)