s-lightly to 180 m in 1982/83. Updrift and downdrift sides of the inlet have 

 been relatively stable since 1920 with only minor erosion updrift between 1920 

 and 1955 and accretion (60 m) of a small spit on the downdrift side between 

 1971 and 1982/83. 

 Fripp Inlet (Map 6) 



122. Fripp Inlet has become progressively offset seaward downdrift 

 through shoreward erosion on the updrift side and accretion downdrift. Down- 

 drift accretion reached its maximum in 1955, having accreted approximately 



1.8 x 10 6 m 2 since 1856/59 (18,000 m 2 /year) . This accretion reversed between 

 1955 and 1962. Little change occurred since 1962 on the downdrift side. Net 

 change between 1955 and 1983 is erosion of 1.4 x 10 6 m 2 (50,000 m 2 /year) . Most 

 change in area is due to onshore/offshore changes; however, there was a net 

 60-m alongshore erosion on the southwest side of the inlet. Alongshore 

 changes updrift had a comparable 60-m accretion. However, between 1856/59 and 

 1955, shoreline erosion resulted in a 2.3 x 10 6 m 2 loss, followed by slight 

 accretion (0.2 x 10 6 m 2 ) by 1982/83. Most of this was due to onshore/offshore 

 sedimentation. Inlet throat width varied only slightly during this period, 

 from 610 m wide in 1856/59 to 790 m in 1964 to 670 m wide in 1982/83. 



St. Helena Sound (Map 6) 



123. In 1856/59, a large spit extended northeast from Hunting Island 

 into St. Helena Sound. Landward shoreline erosion and alongshore erosion on 

 the order of 2,000 m by 1920 resulted in a 6.0 x 10 6 m 2 (99,000 m 2 /year) loss 

 to the spit. Spit erosion continued to 1964 (1.1 x 10 6 m 2 lost, 26,000 m 2 / 

 year) , but alongshore accretion to the northeast dominated between 1964 and 

 1983 (12,000 m 2 , 640 m 2 /year) . With spit losses, the north end of Harbor 

 Island, which lies north of Hunting Island, began accreting. From 1856/59 to 

 1955, it grew about 850 m north into St. Helena Sound. This 0.6 x 10 6 m 2 

 increase in area (10,000 m 2 /year) was followed by an increase between 1920 and 

 1964 (50,000 m 2 ) and a small amount of erosion (200,000 m 2 ) between 1964 and 

 1982/83. Net change to the spit was 7.2 x 10 6 m 2 erosion, with a coincident 



2.9 x 10 6 m 2 growth of Harbor Island. The absence of data between the dates 

 presented here makes it impossible to investigate causal relationships of spit 

 loss and growth of Harbor Island, but it is reasonable to speculate that sedi- 

 ment composing the 1859 spit may have migrated landward to build out Harbor 

 Island. 



107 



