Data for the START file 



356. The initial model configuration is contained in START_INIT. The 

 data in START_INIT represent the first modeling conceptualization of the site. 

 As discussed below, values for many quantities were taken from aerial photo- 

 graphs, whereas other data represent only an initial estimate. Values of 

 selected entries are now reviewed. 



357. Line A. 3 . The lengths of the detached breakwaters are 250 ft and 

 the gaps between them 160 ft. Good resolution requires about 10 cells per 

 breakwater and about 4 cells in the gaps, leading to DX = 25 ft as a reason- 

 able value for describing detail of the breakwater configuration, yet not 

 giving an excessive number of calculation cells. 



358. Line A. 5 . Because the wave data set was constructed with values 

 at 6-hr intervals, as will be discussed below, the time interval DT = 6 hr 

 is taken as a first guess. However, warnings of high values of the stability 

 parameter R s (STAB) are expected, since experience indicates that DX 



= 25 ft is relatively small for use with a 6-hr time interval. The convenient 

 DT = 6 hr is tried to see how large the value of the stability parameter will 

 be under the wave conditions. If high values of R s occur, the value of DT 

 will be reduced until R s falls below 5 or few stability warnings occur. 



359. Line A. 12 . The values of Kl and K2 will be determined in the 

 calibration process. As a first guess, nominal values are chosen. The value 

 of 0.77 is associated with the potential sand transport rate of about 

 21,500 cu yd/year. As the actual annual rate is much lower, the calibrated 

 value of Kl is expected to be smaller than 0.77. 



360. Line B.l . The values of these change parameters may be altered at 

 a later stage, but, as a rule, they are initially set to give no change. 



361. Line C.l . The native sand has a median grain size in the range of 

 about 0.15 to 0.20 mm. However, the median grain size of the fill material is 

 0.40 mm, so the latter value is used, since the fill predominates. 



362. Line C.2 . The design indicates the initial beach fill was placed 

 with a berm elevation of 8 ft. 



363. Line C.3 . The depth of closure is estimated to be twice the 

 maximum annual wave height, which for Lakeview Park is 8 ft according to 

 available wave data, giving a depth of closure of 16 ft. 



156 



