TAMA COUNTYAIRPORT TALL STRUCTURE ZONING ORDINANCE
AN ORDINANCE REGULATING AND RESTRICTING THE HEIGHT OF STRUCTURES AND OBJECTS OF NATURAL GROWTH IN THE VICINITY OF AN AIRPORT BY CREATING THE APPROPRIATE ZONES AND ESTABLISHING BOUNDARIES THEREOF; DEFINING CERTAIN TERMS USED HEREIN; AND IMPOSING PENALTIES.
This Ordinance is adopted pursuant to the authority conferred by Chapter 329.3 of the Code of Iowa. It is hereby found that an Airport hazard endangers lives and property of users of the Airport and property or occupants of land in its vicinity. Accordingly, it is declared:
(1) that the creation or establishment of an obstruction has the potential of being public nuisance and may injure the region served by the Airport.
(2) that it is necessary in the interest of the public health, public safety, and general welfare that creation of Airport hazards be prevented.
(3) that this should be accomplished to the extent legally possible by the proper exercise of police power.
It is further declared that the prevention of the creation or establishment of hazards to air navigation, the elimination, removal, alteration, or mitigation of hazards to air navigation, or the marking and lighting of obstructions are public purposes for which a political subdivision may raise and expend public funds and acquire land or interest in land.
It is hereby ordained by the Tama County Board of Supervisors as follows:
Section I: Short Title
This Ordinance shall be known and may be cited as the Tama County Airport Tall Structure Zoning Ordinance.
Section II: Definitions
1. Airport. The Belle Plaine Municipal Airport of Benton County; the Traer Municipal Airport; the Toledo Municipal Airport, and any public Airport to be constructed in Tama County in the future. This does not include private runways.
2. Airport Elevation. The highest point of the Airport's usable landing area measured in feet above mean sea level.
3. Approach Surface. A surface longitudinally centered on the extended runway centerline, extending outward and upward from the end of the primary surface and at the same slope as the approach zone height limitation slope set forth in Section IV of this Ordinance. In plan the perimeter of the approach surface coincides with the perimeter of the approach zone.
4. Approach, Transitional, Horizontal, and Conical Zones. The zones are set forth in Section III of this Ordinance.
5. Board of Adjustment. A Board created pursuant to the Tama County Zoning Ordinance and consisting of members appointed by the Board of Supervisors as provided in Chapter 329.12 of the Code.
6. Conical Surface. A surface extending outward and upward from the periphery of the horizontal surface at a slope of 20 to 1 for a horizontal distance of 4,000 feet.
7. Hazard to Air Navigation. An obstruction determined to have a substantial adverse effect on the safe and efficient utilization of the navigable airspace.
8. Height. For the purpose of determining the height limits in all zones set forth in this Ordinance and shown on the zoning map, the datum shall mean sea level elevation unless otherwise specified.
9. Horizontal Surface. A horizontal plane 150 feet above the established Airport elevation, the perimeter of which in plan coincides with the perimeter of the horizontal zone.
10. Nonconforming Use. Any pre-existing structure, object of natural growth, or use of land which is inconsistent with the provisions of this Ordinance or an amendment thereto.
11. Nonprecision Instrument Runway. A runway having an existing instrument approach procedure utilizing air navigation facilities with only horizontal guidance, or area type navigation equipment, for which a straight-in nonprecision instrument approach procedure has been approved or planned.
12. Obstruction. Any structure, growth, or other object, including a mobile object, which exceeds a limiting height set forth in Section IV of this Ordinance.
13. Person. An individual, firm, partnership, corporation, company, association, joint stock association, or governmental entity; includes a trustee, a receiver, an assignee, or a similar representative of any of them.
14. Primary Surface. A surface longitudinally centered on a runway. When the runway has a specially prepared hard surface, the primary surface extends 200 feet beyond each end of that runway; for military runways or when the runway has no specially prepared hard surface, or planned hard surface, the primary surface ends at each end of that runway. The width of the primary surface is set forth in Section III of this Ordinance. The elevation of any point of the primary surface is the same as the elevation of the nearest point on the runway centerline.
15. Runway. A defined area on an Airport prepared for landing and take-off of aircraft along its length.
16. Structure. An object, including a mobile object, constructed or installed by man, including but without limitation, buildings, tower, cranes, smokestacks, earth formation, and overhead transmission lines.
17. Transitional Surfaces. These surfaces extend outward at 90 degree angles to the runway centerline and the runway centerline extended at a slope of seven (7) feet horizontally for each foot vertically from the sides of the primary and approach surfaces to where thy intersect the horizontal and conical surfaces. Transitional surfaces for those portions of the precision approach surfaces, which project through and beyond the limits of the conical surface, extend a distance of 5,000 feet measured horizontally from the edge of the approach surface and at 90 degree angles to the extended runway centerline.
18. Tree. Any object of natural growth.
19. Utility Runway. A runway that is constructed for and intended to be used by propeller driven aircraft of 12,500 pounds maximum gross weight and less.
20. Visual Runway. A runway intended solely for the operation of aircraft using visual approach procedures.
Section III: Airport Zones
In order to carry out the provisions of this Ordinance, there are hereby created and established certain zones which include all of the land lying beneath the approach surfaces, transitional surfaces, horizontal surfaces, and conical surfaces as they apply to the Airport. An area located in more than one (1) of the following zones is considered to be only in the zone with the more restrictive height limitation. The various zones are hereby established and defined as follows:
1. Utility Runway Visual Approach Zone. The inner edge of this approach zone coincides with the width of the primary surface and is 250 feet wide. The approach zone expands outward uniformly to a width of 1,250 feet at a horizontal distance of 5,000 feet from the primary surface. Its centerline is the continuation of the centerline of the runway.
2. Utility Runway Nonprecision Instrument Approach Zone. The inner edge of this
approach zone coincides with the width of the primary surface and is 500 feet wide. The approach zone expands outward uniformly to a width of 2,000 feet at a horizontal distance 5,000 feet from the primary surface. Its centerline is the continuation of the centerline of the runway.
3. Horizontal Zone. The horizontal zone is established by swinging arcs of 5,000 feet 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.
4. Conical Zone. The conical zone is established as the area that commences at the periphery of the horizontal zone and extends outward therefrom a horizontal distance of 4,000 feet.
Section IV: Airport Zone height Limitations
Except as otherwise provided in this Ordinance, no structure shall be erected, altered, or maintained, and no tree shall be allowed to grow in any zone created by this Ordinance to a height in excess of the applicable height limit herein established for such zone. Such applicable height limitations are hereby established for each of the zones in question as follows:
1. Utility Runway Visual Approach Zone. Slopes twenty (20) feet outward for each
foot upward beginning at the end of and at the same elevation as the primary surface and extending to a horizontal distance of 5,000 feet along the extended runway centerline.
2. Utility Runway Nonprecision Instrument Approach Zone. Slopes twenty (20) feet outward for each foot upward beginning at the end of and at the same elevation as the primary surface and extending to a horizontal distance of 5,000 feet along the extended runway centerline.
3. Transitional Zone. Slope seven (7) feet outward for each foot upward beginning at the sides of and at the same elevation as the primary surface and the approach surface, and extending to height of 150 feet above the Airport elevation. In addition to the foregoing, there are established height limits sloping seven (7) feet outward for each foot upward beginning at the sides of and at the same elevation as the approach surface, and extending to where they intersect the conical surface. Where the precision instrument runway approach zone projects beyond the conical zone, there are established height limits sloping seven (7) feet outward for each foot upward beginning at the sides of and at the same elevation as the approach surface, and extending a horizontal distance of 5,000 feet measured at 90 degree angles to the extended runway centerline.
4. Horizontal Zone. Established at 150 feet above the Airport elevation.
5. Conical Zone. Slopes twenty (20) feet outward for each foot upward beginning at the periphery of the horizontal zone and at 150 feet above the Airport elevation and extending to a height of 350 feet above the Airport elevation.
6. No structure shall be erected in Tama County that raises the published Minimum Descent Altitude or Decision Height for an instrument approach to any runway, nor shall any structure be erected that causes the Minimum Obstruction Clearance Altitude or Minimum Enroute Altitude to be increased on any Federal Airway in Tama County.
Section V: Use Restriction
Notwithstanding any other provisions of this Ordinance, no use may be made of land or water within any zone established by this Ordinance in such a manner as to create electrical interference with navigational signals or radio communication between the Airport and aircraft, make it difficult for pilots to distinguish between Airport lights and others, result in glare in the eyes of pilots using the Airport, impair visibility in the vicinity of the Airport, create bird strike hazards, or otherwise in any way endanger or interfere with the landing, takeoff, or maneuvering of aircraft intending to use the Airport.
Section VI: Nonconforming Uses
1. Regulations Not Retroactive. The regulations prescribed by this Ordinance shall not be construed to require the removal, lowering or other change or alteration of any structure or tree not conforming to the regulations as of the effective date of this Ordinance, or otherwise interfere with the continuance of nonconforming use. Nothing contained herein shall require any change in the construction, alteration, or intended use of any structure, the construction or alteration of which was begun prior to the effective date of this Ordinance, and is diligently prosecuted.
2. Marking and Lightning. Notwithstanding the preceding provision of this Section, the owner of any existing nonconforming structure or tree is hereby required to permit the installation, operation and maintenance thereon of such markers and lights as shall be deemed necessary by the Tama County Zoning Ordinance Administrative Officer to indicate to the operators of aircraft in the vicinity of the Airport the presence of such Airport obstruction. Such markers and lights shall be installed, operated, and maintained at the expense of the Airport.
Section VII: Variances
1. Variances. Any person desiring to erect or increase the height of any structure, or permit the growth of any tree, or use property, not in accordance with the regulations prescribed in this Ordinance, may apply to the Board of Adjustment for a variance from such regulations. The application for variance shall be accompanied by a determination from the Federal Aviation Administration as to the effect of the proposal on the operation of air navigation facilities and the safe, efficient use of navigable airspace. Such variances shall be allowed where it is duly found that a literal application or enforcement of the regulations will result in unnecessary hardship and relief granted, will not be contrary to the public interest, will not create a hazard to air navigation, will do substantial justice, and will be in accordance with the spirit of this Ordinance. Additionally, no application for variance to the requirements of this Ordinance may be considered by the Board of Adjustment unless a copy of the application has been furnished to the Iowa Department of Transportation Aeronautics Division for advice as to the aeronautical effects of the variance. If the Iowa Department of Transportation Aeronautics Division does not respond to the application within fifteen (15) days after receipt, the Board of Adjustment may act on its own to grant or deny said application.
2. Obstruction Marking and Lighting. Any variance granted may, if such action is deemed advisable to effectuate the purpose of this Ordinance and be reasonable in the circumstances, be so conditioned as to require the owner of the structure or tree in question to install, operate, and maintain, at the owner's expense, such markings and lights as may be necessary. If deemed proper by the Board of Adjustment, this condition may be modified to require the owner to permit the Municipal Airport at its own expense, to install, operate, and maintain the necessary markings and lights.
Section XI: Judicial Review
Any person aggrieved, or any taxpayer affected, by any decision of the Board of Adjustment, may appeal to the Court of Record as provided in Section 414.5 of the Iowa Code.
Section XII: Penalties
Each violation of this ordinance or of any regulation, order, or ruling promulgated hereunder shall constitute a misdemeanor and shall be punishable by a fine of not more than $100 dollars or imprisonment for not more than 30 days and each day a violation continues to exist shall constitute a separate offense.
Section XIII: Conflicting Regulations
Where there exists a conflict between any of the regulations or limitations prescribed in this Ordinance and any other regulations applicable to the same area, whether the conflict be with respect to the height of structures or trees, and the use of land, or any other matter, the more stringent limitation or requirement shall govern and prevail.
Section XIV: Severability
If any of the provisions of this Ordinance or the application thereof to any person or circumstances are held invalid, such invalidity shall not affect other provisions or applications of the Ordinance which can be given effect without the invalid provision or application, and to this end, the provisions of this Ordinance are declared to be severable.
Section XV: Effective Date
Whereas, the immediate operation of the provisions of this Ordinance is necessary for the preservation of the public health, public safety, and general welfare, an emergency is hereby declared to exist, and this Ordinance shall be in full force and effect from and after its passage by the Tama County Board of Supervisors and publication and posting as required by law.
TAMA COUNTY BOARD OF SUPERVISORS
By: /s/ Ferdinand Kvidera, Chairperson, Board of Supervisors; November 2, 1993.
Attest: /s/ John A. Adams, County Auditor
Pursuant to Section 331.302 (8) of the Code of Iowa, the undersigned Auditor of Tama County, Iowa hereby certifies that Ordinance entitled " Tama County Airport Tall Structure Zoning Ordinance" was published once each in the Tama News Herald, Toledo Chronicle, and Traer Star-Clipper newspapers on the ____th day of November, 1993.
/s/ John A. Adams, Tama County Auditor