The AV Aviation Overlay District is intended to provide for the safe operation of aircraft into and out of Seward Municipal Airport, located in Section 5, Township 10 North, Range 3 East in Seward County, Nebraska. The district provides special regulations to maintain adequate clearance and to eliminate potential hazard, safety, and development conflicts between airport operations and surrounding development. The following additional regulations shall apply to such lands within the corporate limits of Seward, Nebraska and its two-mile zoning jurisdiction within the area of three miles in all directions from the boundaries of any airport. This area within three miles of the boundaries of said airport shall be known as the "airport hazard area" and shall be regulated as follows.
A. 
Detailed description of hazard area. The hazard area consists of approach and operation zones, transition zones, and turning zones.
(1) 
The outer boundary of the hazard area is composed of a series of connected tangents and simple curves which also constitute the outer boundaries of the approach and turning zones.
(2) 
The inner boundary of the hazard area is a boundary consisting of a series of intersecting tangents, 500 feet from and parallel to the center line of the instrument runway or landing strip and 250 feet from and parallel to the respective center lines of all other runways or landing strips and connecting the inner boundaries of adjacent approach zones at the ends of the runways, landing strips or proposed runways or landing strips.
B. 
Zone descriptions.
(1) 
An operation zone shall be located at each end of each existing or proposed runway, landing strip or other portion of the airfield used regularly, or to be used regularly, for the landing or taking off of airplanes. Such approach zones shall begin 200 feet beyond the ends of their respective strips and at such beginning shall be 1,000 feet in width for the instrument runway or landing strip and 500 feet in width for all other runways and landing strips. The approach zones shall begin at the ends of their respective operation zones and shall extend and expand uniformly centered along the extended center line of the respective landing strip, to the outer boundary of the approach zone at a rate of 30 feet of width for each 100 feet of horizontal length for the instrument runway or landing strip and 20 feet of width for each 100 feet of horizontal length of all other runways.
(a) 
The inner area of each approach zone shall be that portion of the approach zone beginning 200 feet beyond the end of the respective or proposed landing strip and extending to the intersection of the controlling glide angle with a plane 150 feet above the highest elevations of the end of the respective runway or landing strip.
(b) 
The outer area of each approach zone shall be the area between the inner area of the approach zone and the outer limit of the approach zone.
(2) 
The transition zones shall be the areas bounded by the inner boundary of the hazard area, the sides of contiguous inner areas of approach zones and the outer limits of the transition zones; said outer limits of the transition zones being the intersections, at elevations of 150 feet above the highest elevation at the ends or edges of the closest runway or landing strip, or proposed runway or landing strip, of a series of contiguous planes originating from bases established by the inner boundary of the hazard area and the edges of adjacent inner areas of approach zones; said planes rising from their respective bases at the rate of one foot vertically to seven feet horizontally to the lines of intersection previously referred to.
(3) 
The turning zones shall comprise all portions of the hazard area not contained in the approach zones and in the transition zones. The outer limits of the turning zones shall be a series of points forming a line which is a horizontal distance of three statute miles from the nearest points of the airport's property line boundary.
A. 
Height regulations. No building, transmission line, communication line, pole, tree, smokestack, chimney, wires, tower or other structure or appurtenance thereto of any kind or character shall hereafter be erected, constructed, repaired or established, nor shall any tree or other object of natural growth be allowed to grow:
(1) 
In inner areas of approach zones to a height above the elevation of the nearest point on the end or proposed end of said instrument runway or landing strip in excess of 1/50 and all other runways or landing strips in excess of 1/40 of the distance from the end of the approach zone to said structure or object.
(2) 
In the outer area of approach zones and in turning zones to a height in excess of 150 feet above the elevation at the end or proposed end of the nearest runway or landing strip.
(3) 
In the transition zones to a height above the planes forming the transition slopes.
(4) 
In the existing or proposed operation zones to a height above the existing or proposed finished grade of said runways or landing strips or the surface of the ground.
B. 
Exceptions. In the outer area or approach zones and within the turning zones, these height regulations shall not apply to construction or planting which is no higher than 75 feet above the elevation of the end of the nearest runway or landing strip.
A. 
Permit required. It shall hereafter be unlawful to erect, construct, reconstruct, repair or establish any building, transmission line, communication line, pole, tree, tower, smokestack, chimney, wires or other structure or appurtenance thereto of any kind or character or to plant or replant any tree or other object of natural growth within the boundary of the hazard area of said airport without first obtaining a permit from the Building Official of Seward, Nebraska.
B. 
Application forms. Application for a permit as required under these regulations shall be made upon a form to be available in the office of the Building Official, Seward, Nebraska, and shall indicate the approximate location, ground elevation with reference to the elevation at the end of the nearest runway or landing strip and height of the proposed structure or planting.
A. 
Nonconforming structures. Within the hazard area as hereinbefore defined, no nonconforming building, transmission line, communication line, pole, tree, tower, smokestack, chimney, wires or other structure or appurtenance thereto of any kind or character or object of natural growth shall hereafter be replaced, substantially reconstructed, repaired, altered, replanted or allowed to grow, as the case may be, to a height which constitutes a greater hazard to air navigation than existed before these regulations were adopted; if such structures or objects of natural growth have been torn down, destroyed, have deteriorated or decayed to an extent of 80% or more, or abandoned for a period of 12 months or more. "Transmission lines" and "communication lines" as referred to in these regulations shall be interpreted to mean all poles, wires, guys and all other equipment necessary for the operation and maintenance of same within the zone regulated.
B. 
Marking of nonconforming structures. Whenever the Building Official shall determine, or shall be notified by the Joint Zoning Board or the Nebraska Department of Aeronautics, that a specific nonconforming structure or object exists and has existed prior to the passage of these regulations and within the zones area hereinbefore described at such height or in such position as to constitute a hazard to the safe operation of aircraft landing at or taking off from said airport, the owner or owners and the lessor or lessors of the premises on which such structure or object is located shall be notified in writing by the Building Official and shall within a reasonable time permit the marking thereof by suitable lights or other signals designated by the Building Official. The cost of such marking shall not be assessed against the owner or lessor of said premises.
A. 
Administrative agency. The Building Official of the City of Seward, Nebraska, shall administer and enforce these regulations and shall be the administrative agency provided for in Neb. RS 3-319, and shall have all the powers and perform all the duties of the administrative agency as provided by the Joint Airport Zoning Board.
B. 
Board of Adjustment. The Board of Adjustment of the City of Seward, Nebraska, shall be the Board of Adjustment with respect to these regulations, to have and exercise the powers conferred by Neb. RS 3-320, and such other powers and duties as are conferred and imposed by law.