SURVEY OF COASTAL REVETMENT TYPES 



by 



Bruce McCartney 



I. INTRODUCTION 



Industrial and recreational development have caused shore- front prop- 

 erty in many areas to become very valuable. As land values have increased, 

 concern about the natural process of shoreline erosion has grown. This 

 concern has resulted in the investigation of suitable coastal protection 

 measures . 



The magnitude of coastal erosion in the United States was reported 

 in The National Shoreline Study (U.S. Army, Corps of Engineers, 1971) 

 which listed 20,500 miles of eroding shoreline on the Atlantic, Pacific, 

 gulf, and Great. Lakes. These eroding shorelines include both sheltered 

 beaches with low to moderate wave attack and exposed beaches with a high 

 wave attack. Construction of beach protection can cost as low as $50 per 

 lineal foot on sheltered coasts to in excess of $1,000 per lineal foot on 

 exposed coasts. Assuming an average shore protection cost of $200 per 

 lineal foot, protection of the 20,500 miles of eroding coast would cost 

 over $21 billion. 



Shoreline erosion can be controlled by the following methods of beach 

 protection: (a) revetments, (b) groins, (c) breakwaters, (d) beach res- 

 toration, (e) vegetation, or (f) combinations of two or more of these. 

 Each method has slightly different characteristics so one is usually more 

 suited for a given site than the others. The choice of protection method 

 will depend on the beach character, wave climate, and project purpose. 

 The advantages and limitations of most of these methods are discussed in 

 the Shore Protection Manual (SPM) (U.S. Army, Corps of Engineers, Coastal 

 Engineering Research Center, 1973). 



This report is concerned with revetment types of beach protection 

 that could be constructed of materials available in most areas in the 

 United States. Other beach protection methods will not be discussed 

 further. 



A revetment is defined as a facing of resistant material, such as 

 stone or concrete, built to protect a scarp, embankment, or shore struc- 

 ture against erosion. The major components of a revetment are the armor 

 face, filter, and protective toe (Fig. 1). 



Armor Foce- 



Figure 1. 



Revetment components 



