which may occur in the area (Table 3). Then, this division should be 

 further subdivided into the five primary structural groups: groins^ 

 seawalls and bulkheads , offshore breakwaters ^ revetments^ and miscella- 

 neous types. For each subcategory, the shoreline change rate, volumetric 

 accretion rate, and supplemental data should be compiled. The final 

 output from this data compilation should result in guidelines for shore 

 property owners on what methods result in the greatest benefits per 

 dollar invested. If a substantial number of structures of one type are 

 studied, that subdivision could be further subdivided into concrete, 

 steel, timber, and rubble-mound types. 



Table 3. Categories of upland shore types 



Code 



A 



HBE 



HBN 



LBE 



LBN 



HD 

 LD 

 PE 

 PN 



W 



Type 



Artificial fill area 



High bluff erodible, 30 feet or higher 

 High bluff nonerodible, 30 feet or higher 

 Low bluff erodible, less than 30 feet high 

 Low bluff nonerodible, less than 30 feet high 



High sand dune, 30 feet or higher 

 Low sand dune, less than 30 feet high 

 Erodible low plain 

 Nonerodible low plain 

 Wetlands 



VI. CONCLUDING REMARKS 



The primary reasons for monitoring shore protection structures are 

 to determine if structural maintenance is required and at what cost, 

 and to evaluate whether the installation is effective in combating 

 erosion. A program to maintain structural integrity must continue 

 throughout the life of the structure. These guidelines contain minimum 

 and optimum programs for evaluating the effectiveness of shore protec- 

 tion structures. The concept that a small amount of data is better 

 than none is not always valid, because the small amount of data may 

 indicate performance for a year that is completely different from 

 the long-range, average annual performance. Unless sufficient system- 

 atically collected data are gathered for a number of structures, it 

 will be difficult if not impossible to evaluate the relative effective- 

 ness or economy of different structures. 



Assistance in establishing a monitoring program can be obtained from 

 a U.S. Army Engineer Division or District office. Division and District 

 boundaries, and offices for the Great Lakes, with addresses and phone 

 numbers are shown in Figure 11. 



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