173. Design B: 50-ft berm width. The recession-recurrence interval 
plots for Design B are shown in Figures 43 and 44, and the combined curve is 
shown in Figure 45. The combined storm analysis indicates that maximum reces- 
sions of 50 ft can occur with recurrence intervals of about 30 years. This 
amount of erosion would completely eliminate the flat protective berm region 
fronting the seawall, continued erosion would uncover the face of the seawall, 
rendering it increasingly vulnerable to scour. 
174. Design C: 30-ft berm width. The recession-recurrence interval 
relationships and the combined design curve for Design C are shown in Fig- 
ures 46-48. Results of the combined design curve indicate that maximum 
recessions to the seawall can occur in as short a time as two years. This 
severe recession indicates the vulnerability of the 30-ft design to storms of 
relatively short recurrence intervals. 
48.0 60.0 
TUMANAANNNLUUL 
SNUNTONOUUSTUTT 
PUGCORE BP IBORE 
B.0 
iS 
ira 
z 
° 
7) 
7) 
uu 
oO 
iv) 
a 
= 
2 
= 
~ 
< 
= 
24.0 
12.0 
RECURRENCE INTERVAL (YEARS) 
DESIGN B: 50-FT BERM WIDTH HURRICANES 
Figure 43. Hurricane recession-recurrence plot for 
Design B: 50-ft berm width 
95 
