with inlet location and the length of time the inlet was open, the anomalous 

 island widths shown near latitudes 36°15' and 36°00' most likely reflect pre- 

 1585 inlets. The existence of these sites indicates that the islands have 

 existed in or near their present locations for at least the past 400 years. 



118. Wide portions of barrier islands are usually less susceptable to 

 a new inlet opening than are narrow portions. Thus, while the existence of 

 an anomalously wide island reach often reflects the past site of an inlet, it 

 probably is not a prime site where a new inlet will open. However, ocean and 

 sound hydraulic characteristics, which were once maximized at the previous 

 inlet location, probably did not change much; therefore, that general region 

 remains a potential site for a new inlet. These sites can be identified in 

 Figure 11. 



119. Inlet effects on the ocean coast are rapidly muted after the inlet 

 closes. Within a decade after closure, the effect of an inlet on the adjacent 

 shorelines is no longer noticeable (see New Inlet, for example, in Figure 37). 

 This occurs because alongshore sediment transport and the landward transport 

 of ebb-tidal shoal material act to straighten the ocean side of the previously 

 inward-flaired coast. 



120. Conversely, the effects of an inlet on the sound shoreline may per- 

 sist for hundreds of years (see Kitty Hawk Inlet, for example, in Figure 11). 

 In the years after the inlet closes, the flood-tidal shoals may become islands, 

 or may weld to the adjacent sound shores and spread and become less pronounced 

 with time. 



Capes and shoreline change 



121. Cape influence is reflected in the behavior of adjacent ocean 

 beaches. It appears that changes in the east-facing ocean shoreline at least 

 14 km south of Cape Henry and 10 km north of Cape Hatteras are dominated by 

 the respective capes (Figures 28 and 31). 



122. At Cape Henry the east-facing shoreline prograded while the nearby 

 north-facing shoreline retreated (Figure 44), a situation that will likely 

 continue into the future. The progradation could increase if additional arti- 

 ficial beach fill is placed on Virginia Beach. Some of the recently placed 

 fill material moved north and was deposited along the east-facing shoreline 

 (Figure 28). 



123. The position of Cape Point at Cape Hatteras is highly variable 

 (Figure 41), and its year-to-year movements do not appear to be predictable. 



102 



