REVETMENT - A facing of stone, concrete, etc., built to protect a scarp, 

 embankment, or shore structure against erosion by wave action or 

 currents. 



RIDGE, BEACH - A nearly continuous mound of beach material that has been 

 shaped up by wave or other action. Ridges may occur singly or as 

 a series of approximately parallel deposits. 



RIPARIAN RIGHTS - The rights of a person owning land containing or 

 bordering on a water course or other body of water in or to its 

 banks, bed, or waters. 



RUBBLE-MOUND STRUCTURE - A mound of random- shaped and random-placed 



stones protected with a cover layer of selected stones or specially 

 shaped concrete armor units. (Armor units in primary cover layer 

 may be placed in orderly manner or dumped at random.) 



RUNUP - The rush of water up a structure or beach on the breaking of a 

 wave. Also UPRUSH. The amount of runup is the vertical height 

 above Stillwater level that the rush of water reaches. 



SCARP, BEACH - An almost vertical slope along the beach caused by erosion 

 by wave action. It may vary in height from a few inches to several 

 feet, depending on wave action and the nature and composition of 

 the beach. 



SCOUR - Removal of underwater material by waves and currents, especially 

 at the base or toe of a shore structure. 



SEAWALL - A structure separating land and water areas, primarily 



designed to prevent erosion and other damage due to wave action. 

 See also BULKHEAD. 



SEICHE - (1) A standing wave oscillation of an enclosed water body that 

 continues, pendulum fashion, after the cessation of the originating 

 force, which may have been either seismic or atmospheric. (2) An 

 oscillation of a fluid body in response to a disturbing force having 

 the same frequency as the natural frequency of the fluid system. 

 Tides are now considered to be seiches induced primarily by the 

 periodic forces caused by the sun and moon. (3) In the Great Lakes 

 area, any sudden rise in the water of a harbor or a lake whether or 

 not it is, oscillatory. Although inaccurate in a strict sense, this 

 usage is well established in the Great Lakes area. 



SETUP, WAVE - Superelevation of the water surface over normal surge 

 elevation due to onshore mass transport of the water by wave 

 action alone. 



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