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while the beaches actually suffered a volumetric loss. Clear seasonal trends in 

 the volume of sand above MSL were evident. A net accretion occurred from June 

 through October, while November through May was a period of sand loss. The 

 average seasonal range in sand volume above MSL was 18 cubic yards per foot. 

 The seasonal range of sand volume change within the Sea Isle City groin system, 

 located in the middle of the study area, averaged less than 10 cubic yards per 

 foot. Yearly changes in sand volume varied from a gain of 2.9 cubic yards per 

 foot to a loss of 4.6 cubic yards per foot. Net yearly sand volume changes 

 over the 10-year survey interval averaged -1.12 cubic yards per foot per year 

 (a loss of 40,000 cubic yards per year from the entire island above MSL). The 

 average MSL shoreline retreat rate for the same interval was 8.2 feet per year. 

 The inlets bounding Ludlam Beach are characterized by an erratic shoreline, sub- 

 marine bars, and shoal movements which typify inlets along sandy coasts. Corson 

 Inlet, on the north, widened and migrated south at an average rate of 92 feet 

 per year over the study period. Townsend Inlet migrated southward at an 

 average rate of 9 feet per year. The inlets remove sand from the littoral 

 zone at the expense of downdrift beaches. Thus material is released gradually 

 or abruptly, such as following the March 1962 storm. A sand wave initiated by 

 this unique event contained about 240,000 cubic yards of material which was 

 moved from Corson Inlet southward at an average rate of 5 feet per day. Passage 

 of the sand wave resulted in a time-ordered sequence from north to south of a 

 sand volume gain followed by a voliame loss on the beach profiles. Periods of 

 shoreline advance alternated with periods of shoreline retreat. Groins at Sea 

 Isle City appear to have their greatest effect on the downdrift coast by de- 

 flecting north to south littoral drift offshore. This seaward deflection 

 results in a downdrift "shadow zone" where less than the normal amount of sedi- 

 ment moved offshore is returned. 



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