little authoritative data on its requirements or performance are available. 



In many instances it will be found that alternative solutions of shore 

 problems are indicated by tte analysis of tie physical problemo In other 

 instances there ■mill be a unique solution. TOien a choice is possible the 

 problem analysis should include information on the comparative economic cost 

 in sxifficient detail to permit final selection of a plan of solution on the 

 basis of economic advantage between otherwise equal plans „ It may be found . 

 that two csr more plans are feasible but not eqimlly desirable from a physical 

 viewpoint. In many cases economic cost may be the controlling item dictat- 

 ing the selection of the plan^ even at the expense of desirable physical 

 advantages. 



It is recognized by engineers in this field that many aspects of 

 coastal processes are not clearly understood „ and several institutions have 

 undertaken research programs to improve present knowledge of the various 

 processes. 



Research is conducted in the laboratories of the Beach Erosion Board 

 (and in the field) and is designed to improve knowledge of physical ]aws 

 pertaining to shore processes and design of shore structures for use of the 

 engineering profession, and to compile general information regarding shores 

 of the United States and the forces acting thereon to aid in the solution 

 of engineering problems at specific locations. 



Projects in progress include: (1) a study of the direction and velocity 

 of littoral currents generated by vsves_, Tri.th secondary data on how groins 

 modify littoral currents; and (2) a study of methods of by-passing sand at 

 inlets, which is contributing information on how sand builds up at a jetty, 

 the tidal currents in a jettied inlet, the wave climate in the area, the 

 daily, weekly and bi-monthly changes in the shore line position and bottom 

 topography, the amount of sand transported by waves, and data for relating 

 littoral currents to the generating waves » Laboratory studies include 

 measurements of wave forces against structures with high speed photographs 

 for the study of breaking waves. Another laboratory study is the development 

 of factors that affect the equilibrium profile of beaches.- This same data 

 is used to determine the feasibility of using models to study beaches. 



Over the course of vaanj years the Board has amassed a large amount of 

 basic data on the character of United States shores. Such information con- 

 sists chiefly of the geology of the shore, the wave and wind climates, data 

 on the shore material, and the historical record of changes in shore position 

 and condition c It is planned to continue the collection of this background 

 information, which serves as a reservoir of data available for use in beach 

 erosion control studies, thus reducing thejj: cost and the time required for 

 their completion. 



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