Oceanfront Construction Setback Factors
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North Carolina's oceanfront construction setback factors are calculated using the long-term (approximately 50 years) average annual shoreline change rates for the sole purpose of establishing oceanfront construction Setback Factors, and the Ocean Erodible Areas of Environmental Concern (OEA AEC), which were initially established by the Coastal Resource Commission (CRC) under the Coastal Area Management Act (CAMA) in 1979 .
Oceanfront shoreline change rates have been calculated using the end-point method since the first study completed in 1979. This method simply uses the earliest and most current shoreline data points where they intersect any given shore-perpendicular transect line. The distance between the two shorelines (shore-transect intersect) divided by the time between the two establishes the rate. The use of current mapping and spatial analysis technology make this process repeatable and precise; ESRI's Geographic Information Systems (GIS), and USGS's Digital Shoreline Analysis System (DSAS). To explore shoreline change rates (or erosion and accretion rates) simply use the Google Map provided to zoom in/out, and click on green (accretion) or red (erosion) transect lines to see the rates (feet/year).
Oceanfront Erosion & Accretion Rates:
Shoreline Change Rates (ft/yr) - click transect to view info window.
Oceanfront construction setback is measured landward from the first line of stable natural vegetation, or a static vegetation line when applicable. Setback distance is determined by two variables; (1) size of structure; (2) a setback factor based on shoreline position change rates (see table below). As specified in Rule 15A NCAC 7H .0304(1)(a), the minimum setback factor is 2, unless the shoreline is eroding at a rate greater than 2 feet per year. Therefore, when the shoreline is accreting (moving seaward), or eroding at a rate less than 2 feet per year, the default setback factor is 2. The Google Map below is provided to illustrate current setback factors.
Oceanfront Construction Setback Factors:
SBF = 2
SBF = 2.5 to 4
SBF = 4.5 to 6
SBF = 6.5 to 8
SBF > 8
SBF/OEA Transition Boundary
Construction Setback Factors (SBF) - click lines to view info window.
The shoreline position change rate information presented here is not predictive, nor does it reflect the short-term erosion that can occur during storms. The associated report describes the methodology used to calculate both shoreline position change rates and setback factors, and also provides a summary of rates. The document is not considered to be a "state of the shoreline report," nor was it designed to address "why" the shoreline is accreting or eroding. The most current oceanfront development setback factors and erosion rates depicted in these data were adopted (February-2013) by the Coastal Resources Commission for incorporation into oceanfront setback rules. Please contact your CAMA Local Permit Officer or the nearest regional field office of the N.C. Division of Coastal Management for more information.DCM's Oceanfront Interactive Map Viewer is an interactive map illustrating historic oceanfront data. Currently this site works best with Internet Explorer® (IE). The Division is actively working to release a new map viewer in the summer of 2014 that will function on multiple web browser platforms.