generally fit other beach erosion seasonality data, with these Currituck 

 data having two exceptions, a fall storm season later than usual in 

 1975, and a summer storm in July 1976. 



Generally, a representative beach in Currituck County would be 

 expected to have a beach- face slope of from 2.5 to 6.5 and a sand 

 grain size ranging from 2.5 to 1.5 phi, with both parameters varying 

 widely. The northern two-thirds of Currituck County has a rather broad 

 beach, with low dunes, and has an increasing amount of coarse red sand 

 showing on the beach surface. 



6. Influence of Beach Usage on Beach Behavior. 



The study area is divided into four categories by beach usage: 

 natural, residential, commercial (resort), and military (Fig. 2, Sec. 

 II, 4). The area can also be divided into reaches (Table 2]. Tables 

 10 and 11 examine to what degree this variability in beach usage or 

 geographic reaches is reflected in measured beach changes. 



It does seem apparent from the high accretion in the commercial 

 area of Virginia Beach (Table 11) that the sand nourishment program 

 is both necessary and successful. As for the erosional value for the 

 natural area, many profile lines in this location are eroding, due in 

 part to the high wave energy concentration in this area (Goldsmith, 

 et al., 1974b). The natural processes appear to dominate over usage 

 effects, as shown by the volume change averages (using CERC's compu- 

 tations), and correlate closely with the variations in beach morphology. 

 It appears that the Virginia Beach commercial area would be far more 

 erosional without the extensive sand nourishment and that this beach 

 fill is necessary for the long-term stability of the Virginia Beach 

 commercial beaches (sec. VII, 3). 



VI. RELATIONS BETWEEN PROCESSES AND BEACH CHANGES 

 1 . Storms . 



Storms have definite and sometimes long- lasting effects on beach 

 activity in this area (see Section V) . The factors affecting 

 storm intensity (of those monitored) are wind direction, windspeed, 

 wind duration, barometric pressure, wind-generated seas, and time of 



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