a parametric model. The wave heights were approximately 25% higher while the 

 wave periods were 1.5 to 2 times higher. Although four wave gages were 

 proposed to be installed in the area during our study period: two within the 

 Sound and two offshore from the barrier islands, only two were installed and 

 the available wave data contained too much contamination and hence did not 

 , allow a detailed comparison with the model prediction. Since any 

 overestimation of the wave parameters could lead to overestimation of 

 wave-induced entrainments of sediments, it is our opinion that future studies 

 in the area should include a more careful validation of the wave model. 



Sheng (1980) compared various wave hindcasting models with data from the 

 shallow coastal waters in Lake Erie. It was found that several models, which 

 were originally designed for the deep-water environment, did very poorly in 

 shallow waters. One such model was actually used in a study on wave-induced 

 sediment transport in the Long Island Sound (Bokuniewicz et al., 1977). 



7.5 Deposition, Entrainment, and Transport of Sediments during 

 9/02/80 to 9/05/80 



Ship Survey Data 



Ship surveys were conducted on 9/2/80 and 9/3/80. It was originally 

 planned to take water samples from all the transect stations as shown in 

 Figure 7.24. The 9/2/80 survey covered all the western stations between the 

 Grand Island and the Ship Island. Due to high wave conditions on 9/3/80, the 

 planned survey for the eastern Sound was halted. The water samples collected 

 at half Secchi depth below the surface and 2 feet above the bottom were 

 analyzed by Isphording (1980) for suspended sediment concentrations. His 

 analysis for all stations indicated concentrations near the surface were 

 generally higher than those near the bottom more than twofold. At station 

 T-4, the surface concentration was found to be 596 mg/1 while the bottom 

 concentration was only 13.8 mg/1. Although this is possible to occur locally 

 at some points, it is unlikely that such a remarkably high surface 

 concentration could have prevailed over such a large area under the given 

 climactic conditions. A concurrent measurement on the water turbidity was 

 conducted from the survey ship with a nephel ometer. The nephelometer data at 

 all stations indicated generally higher turbidity near the bottom. It is thus 



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