cross-sectional area and its tidal prism for uncontrolled inlets on the 

 Atlantic Coast is given by Jarrett (1976)* as the following: 



A = 5.37 x 10" 6 P 1 ' 07 

 where 



A = cross-sectional flow area measured at mean sea level, sq ft 

 P = tidal prism of the inlet during spring tide conditions, cu ft 

 Based on this relationship and the minimum flow area of 7,050 sq ft measured 

 in September 1981, Carolina Beach Inlet should have a spring tidal prism of 



Q 



3.32 x 10 cu ft. Of the four discharge measurements listed in Table 7, only 

 the June 1981 observations were made during approximate spring tide condi- 

 tions. The April 1981 and September 1982 measurements were made during peri- 

 ods in which the predicted ocean tide range was slightly less than the mean 

 range, whereas the December 1981 measurements were made during a neap tide. 

 In any event, there is good agreement between the measured flood-tidal prism 

 for Carolina Beach Inlet and that predicted by Jarrett 's relationship. 



Material Size Characteristics 



60. Size characteristics of the material that accumulated in the sedi- 

 ment trap were determined from samples taken from vibracores 1, 2, and 4 

 through 7 located in the sediment trap (Figure 4). The composite characteris- 

 tics of this deposited material and the characteristics of the beach material 

 in 1980, the 1981 emergency fill material, the 1982 renourishment material, 

 and the ocean bar samples at Carolina Beach Inlet are given in Table 8. 



61. There is no true native beach material at Carolina Beach due to 

 previous beach fills; however, the 1980 beach profile samples can be assumed 

 to be representative of native sand since the material had been in place for 

 approximately 9 years prior to sampling. Based on this assumption, material 

 deposited in the Carolina Beach Inlet sediment trap is coarser than the beach 

 material and has a slightly wider range of particle sizes. The deposited 

 material is also similar to the material placed on Carolina Beach in 1981 and 

 1982. If used for beach nourishment, the deposited material would have an 

 overfill factor, as defined in the Shore Protection Manual (1984)* of 

 approximately 1.0. 



* Op cit. 



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