costly approach. Such protection often fails at flanks of these reaches as 

 the adjacent unprotected shores continue to recede. Partial or inadequate 

 protective measures may even accelerate erosion of adjacent shores. Coordi- 

 nated action under a comprehensive plan that considers erosion processes over 

 the full length of the regional shore compartment is much more effective and 

 economical. 



Onshore structures, termed bulkheads, seawalls, and revetments, provide 

 protection, based on their use and design, for the upper beach which fronts 

 backshore development or erodible bluffs. Shore-front owners have resorted to 

 this shore armoring by wave-resistant walls of various types when justified by 

 the economic or esthetic value of what is protected. 



Figure 1-10. Damage after the 1962 storm, Rehoboth Beach, Delaware. 



Bulkheads and seawalls are similar in design with slightly differing pur- 

 poses. Bulkheads are primarily soil-retaining structures which are designed 

 to also resist wave attack. Conversely, seawalls are principally structures 

 designed to resist wave attack but also may retain some soil to assist in 

 resisting wave forces. The land behind seawalls is usually a recent fill 

 area. Bulkheads and seawalls may be built of many materials including steel, 

 timber, or concrete piling, gabions, or rubble-mound structures. 



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