Wave incidence 



Offshore Contours 



Shoreline Contours 

 4At 



Accretion and erosion near a groin, 



with diffraction (two-line theory) 



Wave incidence 



-8At 

 16At 



numerical solution 



Offshore Contours 



Shoreline Contours 



Behavior of beach and inshore between two groins 

 (two-line theory] 



Figure 15. Effect of wave diffraction 

 (from Bakker, 1970) . 



41 



