Standards and Regulations of the Raleigh Airport Overlay District (-AOD)
The Airport Overlay District (-AOD) in the City of Raleigh prohibits all residential and social service uses to protect the public from aircraft noise and ensures that building heights do not interfere with aviation operations. This overlay modifies base standards by requiring full-cutoff lighting, uniform non-reflective rooftops, and specific tree canopy coverage for allowed industrial outdoor uses. Additionally, it supersedes standard height exceptions, often imposing stricter limits determined by the Raleigh-Durham Airport Authority.
Purpose and Applicability
The Airport Overlay District (-AOD) is established by the City of Raleigh to protect the efficiency and long-term usefulness of the area's aviation facilities, highways, and major streets. Its primary objectives include ensuring the attractiveness of significant gateways to the City of Raleigh and protecting the public from the adverse health effects and annoyance caused by aircraft noise [Section 5.1.1.B.1 and Section 5.2.1].
Use Modifications
The Airport Overlay District (-AOD) significantly restricts the types of activities allowed compared to base zoning districts. While uses permitted in the underlying district are generally allowed, the Airport Overlay District (-AOD) prohibits several broad categories to minimize risk and noise exposure.
Prohibited Uses
The following uses are strictly prohibited within the Airport Overlay District (-AOD) regardless of the underlying base district [Section 5.2.1.A.3]:
| Use Category | Prohibited Specific Uses |
|---|---|
| Residential | All household living and all group living. |
| Social Service | All social service uses. |
| Civic | All civic uses (except cemeteries, police, fire, and EMS stations), day cares, and hospitals. |
| Industrial/Other | Detention centers, jails, prisons, resource extraction, and landfills. |
| Signs | Off-premise signs. |
| General Activity | Any use involving dangerous, noxious, or offensive activity (excessive smoke, odor, glare, vibration, or interference with radio/television/radiation). |
Standards for Specific Allowed Uses
For uses involving allowed outdoor storage or concrete and cement mixing plants, the Airport Overlay District (-AOD) requires full shielding via permanent overhead covers or a shade tree canopy. These canopies must meet the following requirements [Section 5.2.1.A.2]:
- Tree Density: At least 1 locally-adapted shade tree for every 2,000 square feet of total site area.
- Canopy Coverage: The expected combined tree canopy must cover at least 35% of the site area at maturity.
- Segmentation: If the site is larger than 5 acres, it must be divided into segments of 5 acres or less, separated by an expected canopy of shade trees at least 100 feet wide.
Dimensional and Development Standards
The Airport Overlay District (-AOD) maintains base district setbacks but heavily modifies height and supplemental design standards to comply with aviation safety.
Height and Setbacks
While the setbacks of the underlying district apply, the height standards are subject to the Raleigh-Durham Airport Authority [Section 5.2.1.B].
| Standard Type | Requirement in the Airport Overlay District (-AOD) |
|---|---|
| Setbacks | Underlying base district setbacks apply. |
| Height Limit | Maximum height limits of the underlying district apply unless the Raleigh-Durham Airport Authority adopts more restrictive limits. |
| Height Encroachments | Typical exceptions (chimneys, flagpoles, parapets) may not exceed established height limits if the site is within an -AOD [Section 1.5.7.D.2]. |
Supplemental Regulations
The City of Raleigh imposes additional design requirements for structures within the Airport Overlay District (-AOD) to prevent pilot distraction and ensure visual uniformity [Section 5.2.1.C]:
- Lighting: All outdoor lighting must be "full cutoff" to prevent light pollution and glare. All illuminated signs must also be shielded so that no direct glare can be seen from above [Section 7.3.16.G.6].
- Rooftops: Rooftops must be uniform in color and constructed of non-reflective materials.
- Special Use Limitations: For religious shelter units, the City of Raleigh prohibits their location within the Airport Overlay District (-AOD) [Section 6.8.2.H.7].
Sections Cited
- Section 1.5.7.D. Height Encroachments
- Section 5.1.1.B. Environmental Overlays
- Section 5.2.1. Airport Overlay District (-AOD)
- Section 6.8.2.H. Religious Shelter Unit
- Section 7.3.2. Signs Allowed by District
- Section 7.3.16.G. Illumination of Signs