way of an expanded beach to an already existing shore protection structure, and/or (b) to 

 counteract the gradual wearing back of a shoreline. In this latter instance, a stretch of beach 

 is, for some reason, not receiving as mucli sand as the waves are transporting away. In cases 

 where beach nourishment is applied, however, the problem being corrected is generally not 

 man-induced, as is usually the case where sand bypassing is required. 



The idea of placing sand onto a shoreUne was not new.* Pumped sand had been used in 

 the 1920's, for example, to enlarge and/or create several recreational beaches near the New 

 York metropolitan area such as Rye Beach^^^ and Coney Island.^ ^^ What was different 

 about these early efforts in New York and those following World War II was essentially one 

 of purpose.^ ^ ^ Sand had been pumped onto Rye Beach to enlarge tlie beach and thereby 

 enable it to accommodate more people for recreation. Beach nourishment, on the other 

 hand, was a "protective" measure.^ ^^ By periodically adding more sand to the "supply" 

 end of a unit of beach, the input into the system would'more closely balance the amount of 

 sand moving out of the system. The intended result would be to create a new equOibrium 

 and thereby stabilize tliat segment of shoreUne. 



Studies had begun to illustrate that beach nourishment was feasible from a purely 

 economic point of view. A second consideration was one of esthetics— periodic beach 

 replenishment normally did not require an array of sometimes unsightly shore protection 

 structures. But more importantly, and to quote Jay V. Hall, Jr., from a paper he wrote on 

 the subject in 1952, "there has developed a growing recognition of the fact that preventing 

 erosion by means of protective structures is a dangerous practice, in the sense that in many 

 cases such protection is secured at the expense of producing an ever-expanding problem 

 area."^^^ To elaborate on Hall's statement, when a coastal structure is built to protect a 

 stretch of beach from erosion by retaining sand or decreasing wave action in the area, that 

 particular stretch of beach is generally preserved. However, the adjoining downdrift segment 

 of shoreline is then exposed to the same wave conditions as before, but these waves are now 

 denied the sand source which had come from the previously unprotected area. This leads to 

 erosion of the adjoining beach. The wave-sand system is still out of balance and as long as 

 this situation prevails, erosion will continue. Beach nourishment deals directly with this 

 problem of imbalance rather than with its symptoms. 



A greater amount of BEB research became concerned with the problems related to beach 

 nourishment. It was found, for example, that the grain-size and size distribution of the 

 material to be placed on a beach were important parameters in a beach replenishment 

 program. The need to know both the gross and the net volume of sand per unit of time 

 moving alongshore was also vitally important. Furthermore, greater emphasis on beach 

 replenishment began to raise questions regarding sand reserves. Well into tlie 1950's, the 

 opinion was that the back-bay areas (i.e., lagoons, estuaries, and sounds) along the Nation's 

 coastline could adequately provide all the material that would be needed for beach 

 nourishment projects. 



*As early as 1916, Elliott J. Dent made the following observation, "The writer knows of no means by which 

 exposed sandy beaches for surf bathing may be preserved, except by feeding fresh beach material to them as 

 rapidly as the old material is carried away. "1^9 



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