(a) Northeast, north-northeast and east-northeast waves o£ periods 

 greater than or equal to 8 seconds are diminished in intensity 

 at the Virginia Beach commercial area because of refraction, 

 except for one small concentration for northeast 12- and 14- 

 second waves. These waves concentrate in Back Bay. 



(b) East and east -southeast waves tend to concentrate wave energy 

 in the Back Bay and Dam Neck areas. 



(c) Southeast and east-southeast waves tend to concentrate energy 

 in the Virginia Beach commercial and residential areas, as 

 well as Back Bay and Dam Neck. 



Previous observations in New Jersey (Goldsmith, Farrell, and 

 Goldsmith, 1974a) indicate a close correlation between differences in 

 beach morphology and areas of relative wave energy concentration, with 

 narrow, steep beaches and wide, low-gradient beaches in areas of high 

 and low wave energy, respectively. Based on the wave refraction data 

 from Goldsmith, et al. (1974b), there appears to be similar relation- 

 ship in this study area, with the narrow beaches in Dam Neck and Back 

 Bay, and the wide beaches at the north and south ends. The wave re- 

 fraction data, indicating large variations in shoreline wave energy 

 distribution, fit the large variations observed in these beach survey 

 data and historical shoreline changes (Goldsmith, 1975c), better than 

 the infrequently observed wave data shown in Figures 19 and 20. 



An additional factor is the dominant northerly transport in the 

 study area, which is related (to an unknown extent) to the relatively 

 high ratio of southeast-northeast wave energy along this shore. An 

 important aspect is the locus of zero net longshore transport (i.e., 

 reversal of transport direction) . This location is concluded to be 

 adjacent to Back Bay on the basis of the combination of: (a) Beach 

 morphology; i.e., narrower, steeper, inactive beaches in the center of 

 the study area, (b) beach response to storms; i.e., slow to recover 

 eroded sediment, (c) total cumulative beach volume changes; i.e., net 

 erosion in the center, and (d) wave refraction; i.e., an area of wave 

 energy concentration for both northeast and southeast waves . 



3. Profile Shapes . 



Beaches are ever-changing in response to the dynamic processes, 

 and as would be expected, the beaches in the study have changed 

 during the interim from September 1974 to November 1976. However, 

 despite these repeated changes, certain shapes are prevalent. 



76 



