PART V: RECOMMENDATIONS 



64. In computing the volume of material required to construct a beach 

 fill having a certain width, the designer must assume that the improved beach 

 profile will parallel the existing beach profile down to some depth of clo- 

 sure. For example, at Carolina Beach, profile slopes seaward of the 25-ft 

 depth are relatively flat and generally outside the normal influence of lit- 

 toral forces. Therefore, in this instance, design volumes were computed as- 

 suming that the improved beach profile would parallel the existing bottom out 

 to -25 ft. 



65. Once the design volume is determined, the only practical way to 

 construct the fill is to place the required quantity on the beach in the form 

 of a sacrificial construction berm. The crest elevation of the construction 

 berm should be equal to the natural berm elevation in the area. The width of 

 the construction berm will depend on the slopes that the material assumes 

 during placement and the volume of material to be placed. Since this slope is 

 not generally known beforehand, surveys should be conducted during placement 

 to ensure that the correct volume of material is distributed along the beach. 

 Once in place, the construction berm material will be displaced to the deeper 

 portions of the active profile by wave action. 



66. Beach fills should be designed with adequate transitions from the 

 artificial beach back to the natural beach. If the transition is too sharp, 

 material will be eroded from the ends of the fill at a rapid rate and could be 

 transported out of the project area. 



67. Sediment traps in tidal inlets should be located in areas removed 

 from the concentrated tidal flows. For example, an ideal location for a sedi- 

 ment trap would be in the area of an existing interior shoal that is fed with 

 littoral material moving off the inlet shoulders. In the case of Carolina 

 Beach Inlet, much of the trap was located in the area of concentrated tidal 

 flows and, as a result, the trap only filled to about 66 percent of its 

 dredged capacity. The trap should also be dredged as deep as possible, but 

 not deep enough to create problems with sloughing of the adjacent shorelines 

 into the trap. 



25 



