missing numbers in the sequence correspond to gages outside the grid segment 

 shown in Plate 7. 



84. Plate 8 shows the match between the computed and prototype tide for 

 10 November 1982 at the four gage locations. The computed signals at 



Gages 2-4 are merely the prototype tide with the datum adjustments added, 

 since these gages are boundary conditions in the model. Computations for tide 

 Gage 1, in the inlet, match the prototype data. 



85. Plates 9-13 compare the model computations of tidal currents to the 

 prototype surface and middepth velocities at ranges 1, 3, and 4. (Solid 

 curves represent numerical results and dashed curves prototype data.) Varia- 

 tions with time of both velocity magnitude and phase are shown over a tidal 

 cycle. Since the numerical model is depth-averaged, in general its results 

 would match the middepth measurements more closely. The agreement between the 

 computations and the prototype data at the inlet (range 1) is excellent, both 

 in magnitude and phase. The ability of the tidal current model to simulate 

 the inlet velocities is crucial to the other aspects of this study, and the 

 model performs this task well. In the case of ranges 3 and 4 (Plates 10-13) 

 the numerical results represent the whole range. The computed and prototype 

 velocities at range 4 (Cumberland Sound) also agree well. The velocity com- 

 parisons at range 3 (St. Marys River) agree in magnitude but differ slightly 

 in phase. This phenomenon is probably due to the drainage characteristics of 

 large marsh areas around St. Marys River which lie outside the boundaries of 

 the tidal model. 



86. Plates 14 and 15 show the computed velocity patterns in St. Marys 

 Entrance for the peak flows of ebb and flood tide. The dashed portions of the 

 barriers represent the permeable sections of the inlet jetties. The flow 

 across the jetties can be seen on these Plates, and it appears that the flow 

 is more pronounced across the south jetty. 



87. In summary, the tide model used prototype gage elevation data for 

 forcing boundary conditions. The measured tidal elevation at the south jetty 

 of the inlet was reproduced in the numerical model. There was good agreement 

 of numerical results with measured velocity data at range 1 in the inlet and 

 satisfactory agreement at interior velocity ranges. Where the flows are 

 influenced by other features in the region interior to the inlet, such as 

 marshes which are not included in the tide model of Model B, close agreement 

 is not expected. This lack of agreement should not cause concern since the 



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