estimate of the peak spectral period and was made using data from the Wave- 

 rider buoy and the seaward-most Baylor gage located at the end of the pier. 

 The deepwater wave angle was computed using this peak period and a wave direc- 

 tion estimated from the radar imagery. The time at which the radar image was 

 taken also is given. Inherent in the procedure used to calculate the wave 

 parameters in deep water is the assumption that the bottom contours seaward of 

 the pier are straight and parallel. This assumption is quite reasonable for 

 this stretch of coastline. The deepwater wave height represents a significant 

 height and was computed using the peak period, deepwater angle, and the sig- 

 nificant height recorded by the offshore Waver ider buoy. The recorded wave 

 spectra at the offshore gage are shown for all six cases in Figure B1 . 



53. Bottom bathymetry is required as model input. The total water 

 depth matrix, used in the model, is computed by simply adding some tidal ele- 

 vation to each depth value. Depth values were taken from one of two surveys 

 shown in Figure B2. The particular survey used for each verification case is 

 shown in Table 1. The tidal elevation (relative to mean sea level (MSL)) also 

 is given in Table 1. The areal extent of each survey is identical, covering 

 1,200 m in the y-direction and 900 m in the x-direction. The orientation of 

 the survey axes was adopted for use in constructing the model grid system. 



The x-axis is parallel to the FRF pier. Actual depth values (relative to MSL) 

 were provided for each cell of a grid comprised of 75 cells in the x-direction 

 and 50 cells in the y-direction. This grid completely encompasses the sur- 

 veyed region. Cell dimensions are 12 and 24 m in the x- and y-directions, 

 respectively. 



54. Comparisons between simulated and observed significant wave heights 

 along the pier are shown for each case in Figures B3 and B4. For these tests, 

 the model is being used to propagate some amount of energy (here, designated 

 by the significant height) with a single frequency and some mean direction. 



By requiring that the radar imagery be clear and contain only a unidirectional 

 wave train, only waves which are nearly planar (long-crested) are being con- 

 sidered. Since most of the wave spectra are narrow-banded (with the exception 

 of Case 4), the cases being considered represent nearly monochromatic condi- 

 tions. Therefore, assumptions inherent in the model's governing equations are 

 essentially upheld, and the model should be able to simulate these conditions. 

 Results show that RCPWAVE accurately predicts wave propagation for these types 

 of wave conditions over a complex bottom. In all cases the scour hole causes 



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