BEDDING 

 LAYER 



GEOTEXTILE 

 FILTER 



BURIED TOE APRON 



BEDDING 

 LAYER 



GEOTEXTILE 

 FILTER 



BERM TOE APRON 

 Figure 7-121. Revetment toe scour aprons for severe wave scour. 



If a revetment is overtopped, even by minor splash, the stability can be 

 affected. Overtopping can (a) erode the area above or behind the revetment, 

 negating the structure's purpose; (b) remove soil supporting the top of the 

 revetment, leading to the unraveling of the structure from the top down; and 

 (c) increase the volume of water in the soil beneath the structure, contribut- 

 ing to drainage problems. The effects of overtopping can be limited by 

 choosing a design height exceeding the expected runup height or by armoring 

 the bank above or behind the revetment with a splash apron. The splash apron 



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