Coastal Areas Suitable for Model Application 



li9. Three types of coastlines have been classified according to 

 suitability for model application along the 5,600 km of the Gulf of Mexico 

 and Atlantic Ocean coasts. These classifications are listed in Table 6. 



Table 6 

 Classification of Coast for Application of Dune Erosion Model 



Percent Gulf and 

 Type Description Examples Atlantic Coast* 



I. Mostly Sand beaches with- South Texas; Florida 54 



suitable out structures or panhandle;Outer Banks, 

 high erosion; with N.C. 

 or without dune- 

 line. 



II. Marginally Limited extent of Portions of New Jersey 24 



suitable sand beaches, coast, southern Maine 



high erosion 

 and/or structured. 



III. Not Typically rocky, Eastern Long Island, 22 



required cliffed, or other N.Y.; Ten Thousand 

 nonsand beaches. Islands, Fla. 



* Percentages are approximate. 



Approximately 22 percent of this coast is nonsandy (mud or rock) where the 

 model is not required and existing FEMA procedures should be used. These 

 regions are classified as Type III. Of the remaining 78 percent, approx- 

 imately 69 percent consists of sandy beaches where use of the model is 

 classified as Type I, "mostly suitable." The remaining coast is classified 

 as Type II, "marginally suitable," either because of high annual erosion 

 rates (greater than 3 m/year) or because of a high concentration of coastal 

 structures. Figure 23 and Table 7 identify the areas which are classified as 

 either marginally unsuitable or not required. 



120. Within the Type I coast, the limitations of the model restrict 

 its use. Obviously, the model should only be applied, and is only required, 

 in areas where the dune crest is higher than the surge level. The Kriebel 

 model will function on low dunes but only up to the point in the surge hydro- 

 graph when the dune is overtopped, a feature which may be useful. Low areas 

 without dunes should be treated as flooded profiles. 



121. Additional care must be exercised in using the models in a Type 

 II zone. If the basic assumptions of the model are satisfied, the results 

 should be meaningful. Potential problem areas are those where strong 



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