?_ 



Crest of berm- 



I —^~ I 



PLAN 

 d_ 



b 



Direction of Littoral Drift 



/ 



Wove OrThogonols'^''''^ 



SECTION 



I 

 d 01 b 



FIGURE 60. THEORY OF THE GROIN 



LAND 

 Resulting Shore Line- 



T — Original Stiore Line 



Groin Field 



Direction of Littoral Drift 



WATER 



FIGURE 61. DESIRED EFFECT OF GROIN FIELD 



79 



