not aid shoreline stability since once the storm is over this material will 

 still be in deeper water and not in the normal littoral regime area. To 

 include this effect in the calculations, material was transported out of the 

 dumped material profile over a surf zone width that covered the normal near- 

 shore transport zone. This normal nearshore transport zone was assumed to be 

 contained within the surf zone which existed 95 percent of the time over the 

 typical year. At Oregon Inlet, this zone extended to a water depth of 

 approximately 2.6 m. 



96. There were two depths at which the dredged material was dumped: 

 11 ft (3.4 m) and 17 ft (5.2 m) . The shape of the dumps was trapezoidal, as 

 provided by SAW (Plates 2 and 3). The dump in 11 ft of water was 11,000 ft 

 long, and the dump in 17 ft was 9,800 ft long. Multiple rows of dumps were 

 used. For example, an initial dump in 11 ft of water was made. The next 

 month the profile was monitored to determine whether or not the material in 

 the dump had moved out of the region sufficiently (no more than a 0.5-ft depth 

 of material remaining) to allow another dump to be made. If a dump could not 

 be made, a second row offshore from the first row was established. The next 

 month the profile was monitored again. If the second row contained material 

 that extended more than 0.5 ft above the base of the first dump location, then 

 it was assumed that the dredge could not pass, and the material was dumped in 

 a third row. The first row location was monitored if the dredge could pass 

 the second row location. If the material could not be dumped in the first row 

 location, it was dumped in the second row location again. A maximum of three 

 rows was allowed for the dumps beginning in 17 ft of water, since it was 

 desired not to dump material in water depths so great that the material would 

 not be transported. Originally, the 17-ft dump was 4,900 ft long, and mate- 

 rial was dumped once a month. However, three rows of material were not suffi- 

 cient for the case (near the end of the year a dredge could not pass the third 

 row and thus could not dump material). Therefore, the row was extended to a 

 length of 9,800 ft, and dumps were made once every 2 months (so that the same 

 total quantity of material was dumped) . The 11-ft dumps were made once a 

 month. Several dumping schedules were tested. First, a year was simulated 

 with dumps beginning in January (both 11- and 17-ft depths) . Then similar 

 calculations were made for years starting in April, July, and October. 

 Table 1 presents the percentage of dumped material transported into the active 

 surf zone in 1 year. Somewhat more material was transported into the active 



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