Section 135B: Airport Safety and Compatibility Overlay (ASCO) Zone
A. Purpose. The Airport Safety and Compatibility Overlay (ASCO) Zone is an overlay zone that supplements the provisions of the underlying zones. The purpose of the ASCO zone is to establish compatibility and safety standards to promote air navigational safety and reduce potential safety hazards for persons living, working or recreating near the Hillsboro Airport, thereby encouraging and supporting its continued operation and vitality.
B. Boundary Delineations and Applicability. The location and dimensions of the Hillsboro Airport runways, civil airport imaginary surfaces, airport noise impact boundaries, and compatibility zones as defined and described in this Section, are delineated for the Hillsboro Airport on Figures 135B 1, 135B 2, 135B 3, and 135B 4. By their inclusion in this Section, these boundaries are made part of the Official Zoning Map.
1. All land, water and airspace, or portions thereof, located within the imaginary surfaces, airport noise impact boundaries, and compatibility zones are subject to the requirements of the ASCO zone. Where the boundary of an imaginary surface, airport noise impact contour, or compatibility zone divides an individual property, the location of that boundary on that property shall be determined by the Planning Director or the Director’s designee upon request by an interested party.
2. Adjustments adopted by the Port of Portland to the airport noise impact boundaries delineated on Figure 135B 3 shall be made to that Figure following completion of a public hearing process as set forth in Section 116 Public Hearing on an Amendment. The public hearing shall be held before the Planning and Zoning Hearings Board, and notice of the hearing shall be provided to owners of properties to be wholly or partially included or excluded in any relocated noise contour boundary as required in Section 116 1 b. Publication of the notice in a general circulation newspaper shall not be required.
C. Definitions.
1. Airport (also referred to as “Hillsboro Airport”). Those properties lying generally north of NE Cornell Road, east of NE 25th Avenue, west of NE Brookwood Parkway, and south of NW Evergreen Road, which are owned and administered by the Port of Portland for general aviation purposes including taking off and landing aircraft. Hillsboro Airport includes airside facilities (runways, taxiways, lighting, markings, signage and navigational aids) and landside facilities (terminals, aircraft storage/maintenance hangars, aircraft parking aprons, and support facilities such as fuel storage, automobile parking, roadway access, firefighting and aircraft rescue). The Hillsboro Airport Runways are illustrated on Figure 135B 1.
2. Airport Safety and Compatibility Overlay Zones: Areas on and near the Hillsboro Airport in which land use and development restrictions are established to protect the safety of the public. The dimensions of the Hillsboro Airport Safety and Compatibility Overlay Zones are based upon guidelines from the California Airport Land Use Handbook which are in turn based on patterns of aircraft accidents at and near general aviation airports. The Airport Safety and Compatibility Overlay Zones dimensions are illustrated and defined on Figure 135B 4 and are generally located as follows:
a. Zone 1 - Runway Protection Zone (RPZ): Trapezoidal areas extending from the runway ends, centered on the extended runway centerlines.
b. Zone 2 - Inner Approach/Departure Zone: A rectangular area extending beyond the RPZ. If the RPZ widths approximately equal the runway widths, the Inner Approach/Departure Zone area extends along the sides of the RPZs from the end of the runway.
c. Zone 3 – Inner Turning Zone: A triangular area over which aircraft are typically turning from the base to final approach legs of the standard traffic pattern. The Inner Turning Zone also includes the area where departing aircraft normally complete the transition from takeoff to climb mode and begin to turn to their en route heading.
d. Zone 4 – Outer Approach/Departure Zone: A rectangular area located along the extended runway centerline beyond the Inner Approach/Departure Zone.
e. Zone 5 – Sideline Zone: A rectangular area in close proximity and parallel to the runway.
f. Zone 6 – Traffic Pattern Zone: An elliptical area that includes the majority of other portions of regular air traffic patterns and pattern entry routes, and generally extends to the farthest points of 6,000 foot radius arcs from the centers of each of the primary surfaces and connecting lines tangent to those arcs.
3. Airport Elevation. The highest point of the Airport’s usable runways, measured in feet above mean sea level.
4. Airport Imaginary Surfaces. The areas established in relation to the airport and to each runway consistent with FAR Part Section 77.25 Civil Airport Imaginary Surfaces in which any object extending above these imaginary surfaces, by definition, is an obstruction. The Hillsboro Airport Imaginary Surfaces area illustrated on Figure 135B 2, and are generally located as follows:
a. Primary Surfaces. A surface longitudinally centered on a runway. The primary surface extends 200 feet beyond the 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. The width of the primary surface for runway 12/30 is 1000 feet, 500 feet for runway 2/20 and 500 feet future runway 12L/30R.
b. Approach surfaces: An aerial surface longitudinally centered on the extended runway centerline and extending outward and upward from each end of the primary surface. An approach surface is applied to each end of the runway based upon the type of approach available or planned for that runway end.
The inner edge of the approach surface is the same width as the primary surface and it expands uniformly to a length of 1,250 feet for runway ends 12L/30R, 1,500 feet for runway ends 2/20, 3,500 feet for runway end 30 and 16,000 feet for runway end 12.
The approach surface extends for a horizontal distance of 5,000 feet at a slope of 20:1 for runway 2/20 and future runway 12L/30R. The approach surface extends for a horizontal distance of 10,000 feet at a slope of 34:1 for runway 30. The approach surface extends for a horizontal distance of 50,000 feet for runway 12 at a slope of 50:1 for 10,000 feet and then 40:1 for the remaining 40,000.
The outer width of the approach surface for future runway 12L/30R is 5,000 feet. The outer width of the approach surface for runway 2-20 is 5,000 feet. The outer width of the approach surface for runway 30 is 50,000 feet. The outer width of the approach surface for runway 12 is 10,000 feet.
c. Transitional Surfaces. Sloping aerial planes extending upward and outward at 90 degree angles to the runway centerlines and the extended runway centerlines. Transitional surfaces rise at a slope of seven (7) feet horizontally for each foot vertically from the sides of the primary and approach surfaces to the points of intersection with 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 a 90 degree angle to the extended runway centerline.
d. Horizontal Surface. A horizontal plane 150 feet above the established airport elevation. The horizontal surface perimeter of the Hillsboro Airport is located at the farthest points of 10,000 foot radius arcs from the centers of each of the primary surfaces and connecting lines tangent to those arcs.
e. Conical Surface. A sloping aerial plane extending outward and upward from the perimeter of the horizontal surface at a slope of 20:1 for a horizontal distance of 4,000 feet.
5. Airport Noise Impact Contour Boundaries. Areas located within 1,500 feet of an airport runway or within established noise contour boundaries exceeding 55 DnL, as defined and demarcated in the most recently adopted Hillsboro Airport Master Plan, and as illustrated on Figure 135B 3. The noise exposures contours on Figure 135B 3 are derived from projected long term noise exposure contours in the most current Hillsboro Airport Master Plan.
6. Avigation Easement. A type of easement which conveys the following rights:
- A right-of-way for free and unobstructed passage of aircraft through the airspace over the property at any altitude above a surface specified in the easement (set in accordance with Federal Aviation Regulations Part 77 criteria).
- A right to subject the property to noise, vibrations, fumes, dust, and fuel particle emissions associated with normal airport activity.
- A right to prohibit the erection or growth of any structure, tree, or other object that would penetrate the imaginary surfaces as defined in this ordinance.
- A right-of-entry onto the property, with proper advance notice, for the purpose of marking or lighting any structure or other object that penetrates the imaginary surfaces as defined in this ordinance.
- A right to prohibit electrical interference, glare, misleading lights, visual impairments, and other hazards to aircraft flight as defined in this ordinance from being created on the property.
7. Building permit. Within Section 135B, a permit issued by the Hillsboro Building Department for structural improvements on a property, excluding permits for electrical, mechanical, plumbing or grading improvements, non-residential tenant improvements, residential remodeling, or any other permit which does not increase the number of residential dwelling units or the square footage of non-residential structures on a property.
8. Commercial Child Care Facility. Any child care facility, other than certified or registered family child care homes or childcare centers used by and operated solely for employees of one or more businesses within the boundaries of the ASCO zone.
9. Commercial Senior or Convalescent Care Facility. Any senior or convalescent care facility, other than licensed residential homes or residential facilities, which provides overnight sleeping rooms for residents’ use.
10. FAA. The Federal Aviation Administration.
11. Height. The highest point of a structure or tree, plant or other object of natural growth, measured in feet above the Airport Elevation.
12. Day-Night Average Sound Level (DNL or Ldn). The noise metric adopted by the U.S. Environmental Protection Agency for measurement of environmental noise. It represents the average daytime noise level during a 24-hour day, measured in decibels and adjusted to account for the lower tolerance of people to noise during nighttime periods. The mathematical symbol is Ldn.
13. Noise Sensitive Uses. Real property normally used for sleeping or as a school, church, hospital, or public library.
14. Obstruction. Any structure or other natural object penetrating an Airport Imaginary Surface.
15. Airport Activity Disclosure Statement. A disclosure statement that acknowledges that a subject property is located within the noise impact boundary and/or the 55 DNL and signifies an owner’s awareness of the noise levels and activities associated with airport operations, such as over flights, vibration and odors.
16. Public Assembly Facility. A permanent or temporary structure, facility, place or activity where concentrations of people gather in reasonably close quarters. Public assembly facilities include, but are not limited to: schools, churches, conference or convention facilities, employment and shopping centers, arenas, athletic fields, stadiums, clubhouses, large museums, and similar facilities and places, but do not include parks, golf courses, fair grounds or similar facilities. Public assembly facilities also do not include air shows, structures or uses approved by the FAA in an adopted airport master plan, or places where people congregate for short periods of time such as parking lots or bus stops.
17. Runway. The defined areas at the Hillsboro Airport constructed and used for aircraft landing and takeoff. Runways at the Hillsboro Airport include existing Runway 12/30, existing 2/20, and future Runway 12L/30R.
18. Structure. For purposes of this Section, any constructed or erected object which requires location on the ground or is attached to something located on the ground. For purposes of this section, structures include but are not limited to buildings, decks, fences, signs, towers, cranes, flagpoles, antennas, smokestacks, earth formations and overhead transmission lines, but do not include concrete or asphalt surfaces exceeding the surrounding ground level by less than six inches.
19. Water Impoundment. A temporary or permanent, human-made body of water, excluding above-ground or in-ground swimming pools, hot tubs, or spas with surface areas less than 650 square feet. Water impoundments include wastewater treatment settling ponds, storm water swales, detention and retention ponds, artificial lakes and ponds, and similar water features. An expansion of an existing water impoundment is considered a new impoundment except where such expansion was authorized by the City prior to November 5, 2009.
D. Compatibility and Safety Standards regarding Height. All structures permitted in the ASCO zone under the standards of the underlying zone shall comply with the height limitations of this Section. Where height limitations of the underlying zone are more restrictive than those of this Section, the underlying zone limitations shall control. Pursuant to Section I, installation of obstruction markers or lighting, or alteration of the structure, may be required on any pre-existing legally constructed structures built or permitted prior to November 5, 2009 not conforming to these standards if the structure is determined to be a potential air navigation hazard.
1. Except as provided in subsections 2 and 3 of this Section, no structure, tree, plant, object of natural growth and temporary structures, such as construction equipment, shall penetrate the Imaginary Surfaces shown on Figure 135B 2.
2. Within the Imaginary Surfaces outside the approach and transition surfaces, where ground elevation exceeds the Airport Elevation to the degree that existing or permitted structures penetrate or would penetrate the primary, conical, or horizontal Surfaces, the City may issue permits for construction of structures up to 35 feet in height.
3. Variances or exceptions to allow structural heights exceeding the standard of the underlying zone may be permitted. Applications for height variances shall be processed as required under Zoning Ordinance Sections 106 through 111, or 136 (X).
4. Proposed structures, trees, plants, objects of natural growth and temporary structures that would penetrate the imaginary surfaces must be reviewed through the FAA’s Obstruction Evaluation / Airport Airspace Analysis process and the applicant must file a Notice of Proposed Construction or Alteration (Form 7460-1) with the FAA. Approval of a variance for increased height within the ASCO may be subject to conditions recommended by the FAA.
E. Compatibility and Safety Standards regarding Noise. Applications for land use approvals, limited land use approvals, or building permits for properties within the boundaries of the ASCO zone received after November 5, 2009 shall demonstrate compliance with the noise disclosure and mitigation requirements of this Section. The requirements of Section E shall not be construed to require the compliance of any pre-existing legally established structure or land use approval not conforming to these requirements.
1. Within the Airport Noise Impact Boundaries shown on Figure 135B 3, recordation of any land division of residentially zoned property shall include recordation of a Airport Activity Disclosure Statement. Any Covenants, Conditions and Restrictions or similar documents shall include citation of the Airport Activity Disclosure Statement. Issuance of a Development Review approval, under Zoning Ordinance Section 133 Development Review / Approval of Plans, for a multi-family residential development not including a land division shall be conditioned to require documentation that an Airport Activity Disclosure Statement is included within any lease or rental contracts. Documentation demonstrating compliance with this standard shall be provided to the Planning Department prior to issuance of a Certificate of Occupancy.
2. Within the Airport Noise Impact Boundaries shown on Figure 135B 3, where airport noise levels are identified at or above 55 Ldn, construction plans submitted for building permit applications for noise sensitive land uses shall include noise abatement methods incorporated into building design and construction as necessary to achieve an indoor noise level not to exceed 45 dBA. Such noise abatement methods may include, but are not limited to: additional insulation; drywall; air conditioning; and/or double- or triple-glazed windows. Building permit applications for construction of noise sensitive uses shall include documentation from a certified acoustician that the building design and construction will achieve an indoor noise level equal to or less than 45 dBA.
F. Compatibility and Safety Standards regarding Development. The following items have the potential to create hazards to aircraft flight. Applications for land use approvals, limited land use approvals, or building permits on properties within the boundaries of the ASCO zone received after November 5, 2009 shall demonstrate compliance with the requirements of this Section. The requirements of Section F shall not be construed to require the compliance of any pre-existing legally established development improvement not conforming to these requirements.
1. Outdoor Lighting. Industrial, commercial, institutional, or recreational uses or facilities shall not use outdoor lighting which projects vertically. Outdoor lighting for all developments shall incorporate shielding in its design to reflect light downward. No outdoor lighting shall be approved which is similar in size, pattern or intensity to airport lighting, and which may impede the ability of pilots to distinguish such outdoor lighting from airport lighting.
2. Reflectivity. Use of exterior metal or glass on the east, west, and south building faces or roofs of new structures shall include any of the following or equivalent methods to reduce the reflectivity of these materials: glare control film or tinting on windows; reduced pane size or overall window area; enlarged mullions; downward-angled windows; exterior louvers, panels, or screens on windows; and matte finishes on metal surfaces. For the purposes of this section, solar panels, collectors and arrays installed with permits issued by the City are not considered reflective materials and are not subject to the provisions of this section.
3. Emissions. Within the ASCO approach surface boundaries, emissions of smoke, dust or steam that could obscure a pilots’ visibility are discouraged. Applications for new industrial, commercial, institutional, or other uses which are anticipated to regularly or intermittently create such emissions shall, during the Development Review process under Zoning Ordinance Section 133, provide documentation that the applicant has consulted with the Port of Portland to ensure that under normal weather conditions such emissions are likely to dissipate and not obscure pilot visibility before reaching the nearest runway approach surface elevation. The City may impose as conditions of approval requirements for reasonable and practical mitigation measures as necessary to ensure that emissions are unlikely to obscure pilot visibility.
4. Communications Facilities and Electrical Interference. No land use, facility, or utility installation shall cause or create radio transmissions or electrical interference at frequencies or levels which may disrupt navigational signals or radio communications between the Airport and an aircraft. Applications or proposals for the location of new or expanded radio, radiotelephone,
andtelevision transmission facilities, electrical transmission lines, or facilities using high frequency electrical impulses in any on-site process within the ASCO zone shall be coordinated with the Port of Portland prior to approval or installation. Approvals of cellular and other telephone or radio communication towers on leased property located within the Airport Imaginary Surfaces illustrated on Figure 135B 2 shall be conditioned to require their removal within 90 days following the expiration of the lease agreement and shall be further conditioned with a requirement to provide a bond or other security to ensure such removal.
5. Water and Waste Water Treatment Facilities: Sewage and industrial waste treatment systems and water treatment systems using permanent open ponds or tanks that attract and sustain wild life populations which pose a threat to the safe operation of fixed wing aircraft are not allowed within the ASCO zone boundaries, with the exception of the following:
- Structural walled flocculation/sedimentation basins, mix basins, and/or structural walled filter basins all with permanently attached structurally framed roofs and open air side walls.
- Closed piped industrial waste treatment such as Acid Waste Neutralization, and solvent waste collection systems used by semiconductor and solar industries are not open waste water treatment facilities.
- Closed piped industrial water treatment systems such as RO / DI plants and associated pre-treatment are not open water treatment facilities.
- Collection, use, or treatment of rainwater or gray water, which does not attract or sustain wild life populations that threaten safe operation of fixed wing aircraft.
G. Compatibility and Safety Standards regarding Land Use.
Within the six Airport Compatibility Zones in the ASCO zone, land uses established after November 5, 2009 shall be limited or restricted as described in this Section. In the event of conflict with the underlying zone, the more restrictive provisions shall control. As used in this section, a limited use means a use that is allowed subject to special standards specific to that use. The requirements of Section G shall not be construed to require the discontinuance of any pre-existing legally established land use not conforming to these requirements.
1. Compatibility Zone 1: Runway Protection Zone
(a) Prohibited land uses include the following: public assembly facilities; residential, commercial, industrial, and institutional land uses; athletic fields, sanitary landfills, water treatment plants, mining, water impoundments, wetland mitigation, and the storage of fuel and other hazardous materials.
(b) Uses and facilities are restricted to those requiring location in Compatibility Zone 1 for which no practicable alternative location exists.
(c) Roads and parking areas may be permitted in Compatibility Zone 1 upon demonstration that there are not practicable alternatives. Plans for lights, guardrails and related road and parking area improvements may be subject to conditions recommended by the Port of Portland based on FAA airport design standards.
(d) No structures are allowed in Compatibility Zone 1, with the sole exception of structures accessory to airport operations whose location within Compatibility Zone 1 has been approved by the FAA.
(e) Utilities, power lines and pipelines shall be underground.
2. Compatibility Zone 2: Inner Approach/Departure Zone
(a) Prohibited land uses include the following: commercial child care facilities; schools; hospitals, commercial senior or convalescent care facilities; and sanitary landfills.
(b) Residential development shall be limited to the densities specified on the Hillsboro Comprehensive Plan Land Use Map as of November 5, 2009. Land use approvals which would increase residential densities above the existing densities as of November 5, 2009 shall not be approved by the City.
(c) Nonresidential development intensity in new developments shall be limited to:
(1) A maximum average intensity of 60 people per gross acre at any time.
(2) A maximum intensity of 120 people on any single gross acre at any time.
(d) Structures shall be located as far as practical from the extended runway centerline.
(e) Land use or limited land use approvals by the City shall be conditioned to provide an avigation easement and an Airport Activity Disclosure Statement to the Port of Portland prior to recordation of land division plats or Certificates of Occupancy, as applicable.
(f) Water impoundments up to 10,000 square feet in surface area are permitted. Applications for water impoundments shall include documentation to the Planning Department that the applicant has consulted with the Port of Portland to ensure that the design of the water impoundment reduces its attractiveness to wildlife and minimizes the risk to aviation.
3. Compatibility Zone 3: Inner Turning Zone
(a) Prohibited land uses include the following: commercial child care facilities; schools; hospitals, commercial senior or convalescent care facilities; and sanitary landfills.
(b) Residential development shall be limited to the densities specified on the Hillsboro Comprehensive Plan Land Use Map as of November 5, 2009. Land use approvals which would increase residential densities above the existing densities as of November 5, 2009 shall not be approved by the City.
(c) Nonresidential development intensity in new developments shall be limited to:
(1) A maximum average intensity of 100 people per gross acre at any time.
(2) A maximum intensity of 200 people on any single gross acre at any time.
(d) Structures shall be located as far as practical from the extended runway centerline.
(e) Land use or limited land use approvals by the City shall be conditioned to provide an avigation easement and an Airport Activity Disclosure Statement to the Port of Portland prior to recordation of land division plats or Certificates of Occupancy, as applicable.
(f) Water impoundments up to 10,000 square feet in surface area are permitted. Applications for water impoundments shall include documentation to the Planning Department that the applicant has consulted with the Port of Portland to ensure that the design of the water impoundment reduces its attractiveness to wildlife and minimize the risks to aviation.
4. Compatibility Zone 4: Outer Approach/Departure Zone
(a) Prohibited land uses include the following: commercial child care facilities; schools; hospitals, commercial senior or convalescent care facilities; and sanitary landfills.
(b) Residential development shall be limited to the densities specified on the Hillsboro Comprehensive Plan Land Use Map as of November 5, 2009. Land use approvals which would increase residential densities above the existing densities as of November 5, 2009 shall not be approved by the City.
(c) Nonresidential development intensity in new developments shall be limited to:
(1) A maximum average intensity of 100 people per gross acre at any time.
(2) A maximum intensity of 300 people on any single gross acre at any time.
(d) Structures shall be located as far as practical from the extended runway centerline.
(e) Land use or limited land use approvals by the City shall be conditioned to provide an avigation easement and an Airport Activity Disclosure Statement to the Port of Portland prior to recordation of land division plats or Certificates of Occupancy, as applicable.
(f) Water impoundments up to 10,000 square feet in surface area are permitted. Applications for water impoundments shall include documentation to the Planning Department that the applicant has consulted with the Port of Portland to ensure that the design of the water impoundment reduces its attractiveness to wildlife and minimizes the risk to aviation.
5. Compatibility Zone 5: Sideline Zone
(a) Prohibited land uses include the following: commercial child care facilities; schools; hospitals, commercial senior or convalescent care facilities; and sanitary landfills.
(b) Residential development shall be limited to the densities specified on the Hillsboro Comprehensive Plan Land Use Map as of November 5, 2009. Land use approvals which would increase residential densities above the existing densities as of November 5, 2009 shall not be approved by the City.
(c) Nonresidential development intensity in new developments shall be limited to:
(1) A maximum average intensity of 150 people per gross acre at any time.
(2) A maximum intensity of 300 people on any single gross acre at any time.
(d) Structures shall be located as far as practical from the extended runway centerline.
(e) Land use or limited land use approvals by the City shall be conditioned to provide an avigation easement and an Airport Activity Disclosure Statement to the Port of Portland prior to recordation of land division plats or Certificates of Occupancy, as applicable.
(f) Water impoundments up to 10,000 square feet in surface area are permitted. Applications for water impoundments shall include documentation to the Planning Department that the applicant has consulted with the Port of Portland to ensure that the design of the water impoundment reduces its attractiveness to wildlife and minimizes the risk to aviation.
6. Compatibility Zone 6: Traffic Pattern Zone
(a) Prohibited land uses include the following: schools; hospitals, commercial senior or convalescent care facilities; sanitary landfills, and publicly-owned water treatment plants.
(b) Water impoundments are permitted. Applications for water impoundments shall include documentation to the Planning Department that the applicant has consulted with the Port of Portland to ensure that the design of the water impoundment has reduced its attractiveness to wildlife and minimized the risk to aviation to the greatest extent practicable.
(c) Applications for increased densities of residential development may be approved if implementation of such increased densities can be conditioned to be constructed consistent with the safety and compatibility standards in this Ordinance regarding building height and noise management. Approvals by the City of increased residential densities shall be conditioned to provide an avigation easement and an Airport Activity Disclosure Statement to the Port of Portland prior to recordation of land division plats or Certificates of Occupancy, as applicable.
(d) There are no nonresidential development intensity limitations in this compatibility zone.
H. Wetland Mitigation, Creation, Enhancement and Restoration
1. To minimize risk and reduce hazards to air navigation near the Airport, the establishment of wetland mitigation banks outside the ASCO zone boundaries is encouraged.
2. Wetland mitigation, creation, enhancement or restoration projects existing or approved on November 5, 2009 and located within the ASCO zone boundaries are recognized as lawfully pre-existing non-conforming uses.
3. Applications to expand existing wetland mitigation projects or to create new wetland mitigation projects within the ASCO zone boundaries shall be permitted only in Airport Compatibility Zone 6 upon demonstration to the Planning Department that:
a. The existing or proposed wetlands have a site-specific ecological function, including but not limited to critical habitat for threatened, endangered or state sensitive species, ground water recharge, etc.
b. The proposed mitigation created will be designed and located to avoid creating a wildlife hazard or increasing hazardous movements of birds across runways or in Airport Compatibility Zones 1-5.
4. Applications to create, enhance or restore wetlands within Airport Compatibility Zones, which include expansion of an existing water impoundment or creation of a new water impoundment, shall be permitted upon demonstration that:
a. The subject wetlands have or will have a site-specific ecological function, including but not limited to critical habitat for threatened, endangered or state sensitive species, ground water recharge, etc; and
b. The proposed wetland will be designed and maintained to avoid increasing hazardous movements of birds feeding, watering or roosting in areas across runways or in Airport Compatibility Zones 1-5.
5. Applications for new or expanded mitigation submitted under Section 3, or applications for wetlands creation, enhancement or restoration submitted under Section 4 shall be coordinated with the Port of Portland.
6. Any approval of new or expanded mitigation submitted under Section 3, or for wetlands creation, enhancement or restoration submitted under Section 4 shall be conditioned as deemed appropriate and necessary by the City to prevent increasing hazardous bird movements across runways and Airport Compatibility Zones 1-5.
I. Nonconforming Structures or Uses
1. The requirements of this Section shall not be construed to require the removal, lowering or alteration of any pre-existing legally constructed structure not conforming to these requirements. These regulations do not require any change in the construction, alteration or intended use of any structure, the construction or alteration of which was approved prior to November 5, 2009.
2. Notwithstanding Section 1 above, if an existing structure is determined by the City, based on FAA obstruction standards, to have an adverse effect on air navigational safety, the provisions of this Section shall be construed to allow the City to require that the owner of that structure to install or allow the installation of obstruction markers, in order to make the structure more visible to pilots.
3. No land use approval, limited land use approval, building permit or other permit shall be issued by the City after November 5, 2009 that would increase any air navigation hazard caused by a pre-existing nonconforming use or structure.
J. Land Use Applications in Airport Safety and Compatibility Overlay Zone.
1. In addition to the materials specified elsewhere in the Zoning Ordinance, applications for land use or limited land use approvals on properties within the ASCO zone shall include the following documentation:
a. Elevation data on the site plan, showing native grade and height of all existing and proposed structures, measured in feet above mean sea level.
b. Vicinity maps showing the location of the subject property in relation to the Imaginary Surfaces shown on Figure 135B 2; the Airport Noise Impact Boundaries shown on Figure 135B 3; and the Compatibility Zone boundaries shown on Figure 135B 4.
c. Documentation of a landscaping plan that is consistent with the standards in Section 5.2.4 Vegetation Management in the Port of Portland’s 2007 Hillsboro Airport Wildlife Hazard Management Plan.
2. The Planning Department shall provide to the Port of Portland notice of City review of applications for quasi-judicial land use or limited land use decisions or legislative decisions such as Comprehensive Plan or Zoning Ordinance text amendments, affecting properties within the ASCO zone, in the same manner and at the same time as notice is provided to surrounding property owners, as required elsewhere in the Zoning and Subdivision Ordinances and in the Comprehensive Plan.
3. Within Compatibility Zones 2, 3, 4, or 5, land divisions such as partitions, subdivisions, or condominiums, and Development Review approvals for multi-family residential development of any size, or non-residential structures exceeding 10,000 gsf, shall be conditioned to require provision to the Port of Portland of an Avigation Easement and an Airport Activity Disclosure Statement. Documentation of the recordation of the Avigation Easement and Airport Activity Disclosure Statement shall be provided prior to issuance of Certificates of Occupancy.
(Added by Ord. No. 5929/10-09)