t r 



SEAWALL SLOPE 1:1 I 

 NO BERM 



ANGLE OF ATTACK 



Figure 19. Effect of angle of wave 

 attack (from Owen 1982) 



depth decreases the relative freeboard F/H,. 



Not only does a rise in water 



level decrease the freeboard F , but it also allows higher waves to reach the 

 structure if the waves are depth limited. Figures 8, 11, 15, 16, and 17 all 

 show the dramatic dependence of overtopping on relative freeboard F/H s . 

 Therefore, a varying water level, such as a tide or a storm surge, will cause 

 the overtopping rate to vary significantly through time. 



36 



