distribution and amount of sand. The sources of material may be either 

 from land or offshore. The methods of placement include placing sand 

 directly on the beach along the entire length of the project, placing it in 

 stockpiles at a feeder beach at one end of the site, and placing it as an 

 offshore bar. The grain size of the materials used should be larger than, 

 or at least the same size as, the original beach material. If coarser 

 sands are used in the beach restoration, the equilibrium slope will be 

 steeper than the existing one, and vice versa for finer particles. A more 

 detailed presentation on beach nourishment may be found in Chapters 5 and 6 

 of the SPM (U.S. Army, Corps of Engineers, CERC, 1977). 



A subsand filter system (gravel filter bedding layer placed in the 

 foreshore or offshore zones) may be useful in the stabilization of offshore 

 profiles. Preliminary studies have indicated that such filters may have a 

 stabilizing effect on the bed material in the offshore zone and that they 

 may be effective in speeding accretion in the foreshore zone. The latter 

 use may be employed for berm building or berm replacement (Machemehl, 

 French, and Huang, 1975). 



The construction of dunes is another type of nonstructural erosion 

 mitigation. Dunes are constructed or enhanced by the placement of sandfill 

 and by the planting of stabilizing vegetation. Snow fences may also be 

 used to physically retain initial sand. Dunes are generally constructed 

 parallel to and behind the beach proper and serve to trap and absorb sand 

 which is transported by onshore winds, storm overwash, or offshore winds 

 blowing over overwash plains. The construction and stabilization of sand 

 dunes is discussed in Chapters 5 and 6 of the SPM (U.S. Army, Corps of 

 Engineers, CERC, 1977). 



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