It is determined that an airport hazard endangers the lives and property of users of airports, and the health, safety and welfare of property or occupants of land in its vicinity and, also, if of the obstruction type or of the incompatible use type in effect reduces the size of the area available for landing, takeoff and maneuvering of aircraft, thus tending to destroy or impair the utility of airports and the public investment therein. Accordingly, it is declared that:

1. The creation or establishment of an airport hazard is a public nuisance and an injury to the region served by airports;
2. It is necessary in the interest of public health, public safety and general welfare that the creation and establishment of airport hazards be prevented; and
3. The prevention of these hazards should be accomplished, to the extent legally possible, by the exercise of the police power without compensation.

In this chapter, the following terms, phrases, words, and their derivations, shall have the meanings as defined in this section:

"Air circulation system" means any method of cooling and heating an area with windows and doors closed, or with evaporative coolers and similar devices.

"Airport" means any landing area, runway, or other facility designed, used or intended to be used either publicly or by any person or persons for the landing or taking off of aircraft, including all necessary taxiways, aircraft storage and tiedown areas, hangars, and other necessary buildings and open spaces, as permitted by local zoning ordinances.

"Airport elevation" means the highest point of the airport's usable landing area, measured in feet from mean sea level.

"Airport hazard" means any structure or object of natural growth located on or in the vicinity of the airport, or any use of land near the airport, which obstructs the airspace required for the flight of aircraft in landing or takeoff of an aircraft.

"Airport reference point" means the point established as the approximate geographic center of the airport landing area, and so designated.

"FAA" means the Federal Aviation Administration.

"Height." For the purpose of determining the height limits in all zones set forth in this chapter and shown on the zoning map, the datum shall be mean sea level elevation unless otherwise specified.

"Incompatible use" means any structure or use of land which, because it exposes residents or occupants in the vicinity of airports to aircraft noise, constitutes an airport hazard.

"Nonconforming use" means any preexisting structure, tree or use of land which is inconsistent with the provisions of this chapter or an amendment thereto.

"Nonprecision instrument runway" means a runway having an existing instrument approach procedure utilizing air navigation facilities, with only horizontal guidance or area-type navigation equipment for which straight-in nonprecision instrument approach procedure has been approved or planned, and for which no precision approach facilities are planned or indicated on an FAA planning document.

"Person" means an individual, firm, partnership, corporation, company, association, joint stock association or governmental entity. It includes a trustee, receiver, assignee or similar representative of any of the foregoing.

"Precision instrument runway" means a runway having an existing instrument approach procedure utilizing an instrument landing system ("ILS") or a precision approach radar ("PAR"). It shall also mean a runway for which a precision approach system is planned and is so indicated on an FAA approved airport layout plan or any other FAA approved planning document.

"Primary surface" means a surface longitudinally centered on a runway. When the runway has a specially prepared hard surface, the primary surface extends two hundred feet beyond each end of such runway; but when the runway has no specially prepared hard surface, or planned hard surface, the primary surface of a runway will be that width prescribed in Part 77, Section 77.24 of the Federal Aviation Regulations ("FAR"), which is hereby incorporated by reference and made a part hereof, for the most precise approach existing or planned for either end of that runway. The elevation of any point on the primary surface is the same as the elevation of the nearest point on the runway centerline.

"Runway" means a defined area on the airport prepared for landing and takeoff of aircraft along its length.

"Structure" means an object constructed or installed by man, including, but without limitation, buildings, towers, smokestacks, earth foundations and overhead transmission lines.

"Tree" means any object of natural growth.

"Utility runway" means a runway that is constructed for and intended to be used by propeller-driven aircraft of twelve thousand five hundred pounds maximum gross weight or less.

"Visual runway" means a runway intended solely for the operation of aircraft using visual approach procedures with no straight-in instrument approach procedure and no instrument designation indicated on an FAA approved airport layout plan or on any planning document submitted to the FAA by competent authority.

Except as otherwise provided in this chapter, no structure or tree shall be erected, altered, allowed to grow or be maintained in any zone created by this chapter to a height in excess of the applicable height limit established in this chapter for such zone.

Utility runway visual approach zones are established with the inner edge coinciding with the width of the primary surface, and being two hundred fifty feet wide. The approach zone expands outward, uniformly, to a width of twelve hundred fifty feet at a horizontal distance of five thousand feet from the primary surface, its centerline being the continuation of the centerline of the runway.

The height limitation in a utility runway visual approach zone slopes upward twenty feet horizontally for each foot vertically, beginning at the end of and at the same elevation as the primary surface, and extends to a horizontal distance of five thousand feet along the extended runway centerline.

Runways larger than utility with a visible minimum as low as three-fourths' mile nonprecision instrument approach zones are hereby established, with the inner edge of this approach zone coinciding with the width of the primary zone, and are one thousand feet wide. The approach zone expands outward, uniformly, to a width of sixteen thousand feet at a horizontal distance of fifty thousand feet from the primary surface, its centerline being the continuation of the centerline of the runway.

The height limitation in a runway larger than utility with a visual minimum as low as three-fourths' mile nonprecision instrument zone slopes upward one hundred feet horizontally for each foot vertically, beginning at the end of and at the same elevation as the primary surface, and extends to a horizontal distance of ten thousand feet along the extended runway centerline; thence slopes upward forty feet horizontally for each foot vertically to an additional horizontal distance of forty thousand feet along the extended runway centerline.

Precision instrument runway approach zones are hereby established, with the inner edge of this approach zone coinciding with the width of the primary surface, and are one thousand feet wide. The approach zone expands outward, uniformly, to a width of sixteen thousand feet at a horizontal distance of fifty thousand feet from the primary surface, its centerline being the continuation of the centerline of the runway.

The height limitation in a precision runway approach zone slopes upward one hundred feet horizontally for each foot vertically, beginning at the end of and at the same elevation as the primary surface, and extends to a horizontal distance of ten thousand feet along the extended runway centerline; thence slopes upward forty feet horizontally for each foot vertically to an additional distance of forty thousand feet along the extended runway centerline.

Transitional zones are hereby established as the area beneath the transitional surfaces. The surfaces extend outward and upward to ninety-degree angles to the runway centerline and the runway centerline extended, at a slope of seven feet horizontally for each foot vertically from the sides of the primary and approach surfaces to where they intersect the horizontal and conical surfaces. Transitional zones for those portions of the precision approach zones which project through and beyond the limits of the conical surface extend a distance of five thousand feet, measured horizontally from the edge of the approach zones and at a ninety-degree angle to the extended runway centerline.

1. The height limitation in a transitional zone slopes upward and outward seven feet horizontally for each foot vertically, beginning at the side of and at the same elevation as the primary surface and the approach zones, and extending to a height of one hundred fifty feet above the airport elevation.
2. In addition to the foregoing, there are established height limits sloping upward and outward seven feet horizontally for each foot vertically, beginning at the sides of and at the same elevation of the approach zones, and extending to where they intersect the conical surface.
3. Where the precision instrument runway approach zone projects beyond the conical zone, height limits sloping upward and outward seven feet horizontally for each foot vertically shall be maintained beginning at the sides of and at the same elevation as the precision instrument runway approach surface, and extending to a horizontal distance of five thousand feet, measured at a ninety-degree angle to the extended runway centerline.
   

1. Horizontal zones are hereby established as that area the perimeter of which is constructed by swinging arcs of specified radii from a point on the centerline and two hundred feet beyond each end of each runway, and connecting the adjacent arcs by lines tangent to those arcs.
2. The radius of each arc is five thousand feet for all runways designated as utility or visual, and ten thousand feet for all other runways. The radius of the arc specified for each end of a runway will have the same arithmetical value. That value will be the highest determined for either end of the runway. When a five-thousand-foot arc is encompassed by tangents connecting two adjacent ten-thousand-foot arcs, the five-thousand-foot arc shall be disregarded in determining the horizontal zone.
3. The horizontal zone does not include the approach and transitional zones.
   

The height limitation in a horizontal zone shall be one hundred fifty feet above the airport elevation.

Conical zones are hereby established as the area that commences at the periphery of the horizontal zone and extends outward therefrom a horizontal distance of four thousand feet. The conical zone does not include the precision instrument approach zones and the transitional zones.

The height limitation of the conical zone shall slope upward and outward twenty feet horizontally for each foot vertically, beginning at the periphery of the horizontal zone and at one hundred fifty feet above the airport elevation, and extending to a height of three hundred fifty feet above the airport elevation.

Nothing in this chapter shall be construed as prohibiting the growth, construction or maintenance of any tree or structure to a height consistent with the terms of this chapter.

Airport restriction zones are established as follows:

1. Airport Restriction Zone A is that area shown on the airport zoning map exposed to the most severe levels of aircraft noise.
2. Airport Restriction Zone B is that area shown on the airport zoning map exposed to severe levels of aircraft noise.
3. Airport Restriction Zone C is that area shown on the airport zoning map exposed to moderate levels of aircraft noise.
4. Airport Restriction Zone D is that area shown on the airport zoning map exposed to noise from aircraft operating on a primary flight track.
5. Airport Restriction Zone E is that area shown on the airport zoning map exposed to noise from aircraft operating on a heavily used aircraft traffic pattern.

1. Except as provided for in this chapter, no structure or use of land shall be erected, altered or utilized in any airport restriction zone so as to create an incompatible use, as hereinafter established for such zones. In addition, any development within Airport Restriction Zones A, B, C, D or E requires an aviation easement.
2. For this purpose, "development" means and is defined as subdivision of property and as construction of buildings on vacant property, except on improved subdivided property recorded as of the effective date of the ordinance codified in this chapter.
3. Airport Restriction Zone A. The following uses are incompatible in this zone:
   1. Residential uses;
   2. Commercial uses, except those constructed with air circulation systems and at least twenty-five db of sound attenuation;
   3. Institutional uses, such as schools, hospitals, churches and rest homes;
   4. Hotels and motels, except those constructed with air circulation systems and at least thirty db of sound attenuation in sleeping areas, and at least twenty-five db of sound attenuation elsewhere.
4. Airport Restriction Zone B. The following uses are incompatible in this zone:
   1. Residential uses, except residences in agricultural zones with air circulation systems, and at least twenty-five db of sound attenuation;
   2. Institutional uses such as schools, hospitals, churches and rest homes, except those constructed with air circulation systems and at least twenty-five db of sound attenuation;
   3. Hotels and motels, except those constructed with air circulation systems and at least twenty-five db of sound attenuation in sleeping areas.
5. Airport Restriction Zone C. The following uses are incompatible in this zone:
   1. Residential uses, except those constructed with air circulation systems;
   2. Mobile homes, except those constructed with air circulation systems and at least twenty db of sound attenuation;
   3. Institutional uses such as schools, hospitals, churches and rest homes, except those constructed with air circulation systems.
6. Airport Restriction Zone D. The following uses are incompatible in this zone:
   1. Low-density residential and school uses except those constructed with air circulation systems.
7. Airport Restriction Zone E. The following uses are incompatible in this zone:
   1. No restrictions, except aviation easements are required.
      

All uses shall obtain permits before construction or installation, as required by other county ordinances.

No permit shall be granted that would allow the establishment or creation of an airport hazard, or permit a nonconforming use or structure to be made or become higher or become a greater hazard to air navigation than it was on the effective date of the ordinance codified in this chapter, or any amendment thereto, or than it is when the application for a permit is made.

Notwithstanding any other provision of this chapter, no use may be made of land or water within the county that will create any electrical interference with navigational signals for radio communication between the airport and the aircraft, making it difficult for pilots to distinguish airport lights and others, resulting in glare in the eyes of the pilots using the airport, impair visibility in the vicinity of the airport, or otherwise in any way create a hazard or endanger the landing, takeoff or maneuvering of aircraft intending to use the airport.

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 property owner at his 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.

The regulations prescribed in this chapter shall not be construed to require the removal, lowering, or other changes or alterations in any structure or tree not conforming to the regulations as of the effective date of the ordinance codified in this chapter, or otherwise interfere with the continuance of a 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 the ordinance codified in this chapter and which is diligently prosecuted.

Notwithstanding the provisions of Section 19.70.250, the owner of any existing nonconforming structure or tree is required to permit the installation, operation and maintenance thereon of such markers and lights as shall be deemed necessary, by the airport manager, to indicate to the operators of aircraft in the vicinity of the airport hazards.

Whenever the county development services director determines that a nonconforming structure has been abandoned for a period of twelve consecutive months, or physically deteriorated as defined in Section 203 of the Uniform Building Code, no permit shall be granted that would allow such structure to exceed the applicable height limit or otherwise deviate from the zoning regulations.

Where there exists a conflict between any of the regulations or limitations prescribed in this chapter and any other regulations applicable to the same area, including land use zoning, whether the conflict is with respect to height of structure or trees, the use of land, or any other matter, the more stringent limitation or requirements shall govern and prevail. Also, where an area is covered by more than one height limitation described in this chapter, the more-restrictive limitation shall prevail.