ogies, such as a shoreline change model (e.g., Kraus 1983, Kraus , Hanson, and 

 Harikai 1985), which compute the time rate of change of shoreline position 

 based on estimates of wave -induced longshore sand transport. 



The model produced realistic results in test calculations of profile 

 adjustment of hypothetical nourishment projects, giving proper trends of 

 erosion and accretion, including bar and berm formation, with respect to grain 

 size of the beach material, wave steepness, change in water level, and initial 

 profile configuration. The capability to reproduce beach recovery was also 

 demonstrated to some extent. This capability is needed for long-term simula- 

 tions, since beaches exhibit recovery during mild wave conditions and between 

 storms . 



Comparison of model results for the adjustment of a standard berm- type 

 beach fill and a fill distributed over the profile in equilibrium form (the 

 "Bruun beach fill") showed that the Bruun fill better resisted erosive action 

 caused by steep storm waves and high surge. The Bruun fill, however, has 

 greater potential for depletion through longshore transport, since more 

 material is located in the active littoral zone. An artificial berm is 

 probably more economical to construct than a Bruun fill and provides protec- 

 tion against inundation brought by high wave setup and surge. Where surge is 

 a problem, combination of a high berm and a Bruun fill might provide the 

 optimal protective design. 



The economics of a fill depend on location of the material, access to the 

 beach, type of equipment available, and the projected longevity of the fill. 

 The present model can be used to provide guidance on the latter factor. The 

 model can be used as a design and planning tool to assist in evaluating the 

 efficiencies and benefits of proposed beach fill schemes, taking into account 

 in a quantitative way such factors as fill volume and cross-section, grain 

 size, waves, surge, and frequency of occurrence of storms. 



ACKNOWLEDGEMENTS 



We would like to thank Ms. Kathryn Gingerich and Dr. Norman Schef f ner , 

 colleagues at the Coastal Engineering Research Center, for helpful discus- 

 sions, and Mrs. Kinuyo Kraus for assistance in preparing the figures. 



This research was conducted by the work unit "Surf Zone Sediment Transport 

 Processes" under the Shore Protection and Restoration Program of the United 



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