occurring additions of volume to the beach and those associated with impoundment at the jetty. 

 Changes in sand volume for this same area from 1929 to 1956 show net accretion of 

 4.12±1.46Mcy (natural beach volume additions). Dredging records indicate that sand 

 deposition in two well-defined areas along the north side of the entrance channel occurs at a rate 

 of 67,000 to 99,000 cy/year (Bodge 1994). This range of deposition rates represents the quantity 

 of sand transported through and around the north jetty. 



Given these data, the net longshore transport rate in the vicinity of the Harbor is determined 

 as the sum of sand accumulation north of the north jetty (8.36 Mcy over 40 years gives 

 209,000 cy/year) and the rate of sand deposited along the edge of the north channel (maximum 

 deposition in two areas along the edge of the north channel is 99,000 cy/year). Consequently, 

 southerly directed, net long-term sand transport north of the Harbor (equal to net long-term sand 

 accumulation at the total littoral barrier) has been occurring at a rate of approximately 308,000 

 ±28,000 cy/year. The amount of sand that was transported to beaches south of this point prior to 

 Harbor construction is obtained by subtracting the net accretion rate in this area from 1929 to 

 1956 (4.12Mcy/year over 27 years, or 153,000 ±41,000 cy/year) from the total sand 

 accumulation rate of 308,000 cy/year. The resultant sand-bypassing rate is 155,000 



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±26,000 cy/year. This rate of sand bypassing is equivalent to 6.4 ±1.1 Mcy of sand for the past 

 41 years (1956 to 1997). 



Approximately 6.3 Mcy of sand have been placed on or along the shore south of Canaveral 

 Harbor in Brevard County, of which 4.0 Mcy were placed by the USACE and local sponsors 

 within a 1 7,000-ft-long zone directly south of the Harbor, where evidence of Harbor-induced 

 erosion exists. The remaining 2.3 Mcy of sand were placed on beaches or in nearshore disposal 

 areas located farther than 17,000 ft south of the Harbor. Consequently, from 1956 to 1997, the 

 supplied volume of 6.3 Mcy replaced the sand that would have been transported south by the 

 longshore current, if not for the Harbor. 



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Furthermore, approximately 90% of the plaintiffs purchased their properties after 1972. If 

 155,000 cy/year had been bypassed between 1972 and 1997, 3.9 Mcy would have been placed, 

 which is equivalent to the amount of material (4.0 Mcy) placed by the USACE within the first 

 17,000 ft south of the Harbor. Calculation of shoreline-position change from measurements 



The USACE would not have bypassed 155,000 cy each year since 1972. If the USACE had started to bypass sand in 

 1972, it would have been based on the data in the 1962 authorization, and the rate of 350,000 cy/year was the stated goal 

 at that time. The USACE did not change (lower) its estimate of bypassing until the 1987 General Design Memorandum for 

 the Sand Transfer Plant. In 1987, the USACE estimated the net deficit for the first 2.1 miles south of the Harbor to be 

 136,000 cy/year, after tightening of the south jetty. The current USACE sand-bypassing rate is based on the 1993 General 

 Re-evaluation Report rate of 106,000 cy/year. Although the 1996 USACE Feasibility Report (Appendix A, Paragraph A-96) 

 for the Brevard County Shore Protection Project recommended a bypassing rate increase to 156,000 cy/year, this rate has 

 not yet been implemented by the USACE. The amount of material for each future sand bypassing will be based on 

 monitoring surveys of the borrow and disposal areas for the sand bypassing. 



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Of these 90%, 50% purchased in the 1980s and 28% purchased in the 1990s. 

 3-12 Chapter 3 Assessment of Coastal Change 



