7-1-3: AIRPORT ZONES:
In order to carry out the provisions of this chapter, there are hereby created and established certain zones for existing and future planned airport conditions as they apply to a particular airport. These zones include all the land lying within the primary zones, approach zones, transitional zones, horizontal zones and conical zones. Such zones are shown on the St. Maries airport hazard zoning map consisting of one sheet prepared by J-U-B Engineers, Inc., and dated January 1977, which is attached to this chapter and made a part hereof. Whenever the zoning map shows zones for future planned airport improvements, the more stringent future planned zones govern. Their limitations and boundaries shall be adapted for present zoning purposes. The various zones are hereby established and defined as follows:
   A.   Utility Runway Visual Approach Zones: These zones are hereby established as the area beneath the approach surfaces. The inner edge of this approach zone coincides with the width of the primary surface and is two hundred fifty feet (250') wide. The approach zone expands outward uniformly to a width of one thousand two hundred fifty feet (1,250') at a horizontal distance of five thousand feet (5,000') from the primary surface, its centerline being the continuation of the centerline of the runway.
   B.   Transitional Zones: These zones are hereby established as the area beneath the transitional surfaces. These surfaces extend outward and upward at ninety degree (90°) angles to the runway centerline and the runway centerline extended at a slope of seven feet (7') horizontally for each foot vertically from the sides of the primary and approach surfaces to where they intersect the horizontal surface.
   C.   Horizontal Zone: This zone is hereby established as the area below the horizontal surface. The horizontal zone perimeter is delineated by swinging arcs of five thousand feet (5,000') radii from the center of each end of the primary surface of each runway, and connecting the adjacent arcs by drawing lines tangent to those arcs. The horizontal zone does not include the approach and transitional zones.
   D.   Conical Zone: This zone is hereby established as the area below the conical surface. The conical zone is the area that commences at the periphery of the horizontal zone and extends outward therefrom a horizontal distance of four thousand feet (4,000'). (Ord. 16, 6-12-1978)