RIP SURF. See RIP CURRENT. 



RIPARIAN. Pertaining to the banks of a body of water. 



RIPARIAN RIGHTS. The rights of a person owning land containing or bordering 

 on a watercourse or other body of water in or to its banks, bed, or 

 waters. 



RIPPLE. (1) The ruffling of the surface of water; hence, a little curling 

 wave or undulation. (2) A wave less than 0.05 meter (2 inches) long 

 controlled to a significant degree by both surface tension and gravity. 

 See CAPILLARY WAVE and GRAVITY WAVE. 



RIPPLES (bed forms). Small bed forms with wavelengths less than 0.3 meter (1 

 foot) and heights less than 0.03 meter (0.1 foot). 



RIPRAP. A protective layer or facing of quarrystone, usually well graded 

 within wide size limit, randomly placed to prevent erosion, scour, or 

 sloughing of an embankment of bluff; also the stone so used. The 

 quarrystone is placed in a layer at least twice the thickness of the 50 

 percent size, or 1.25 times the thickness of the largest size stone in the 

 gradation. 



ROLLER. An indefinite term, sometimes considered to denote one of a series of 

 long-crested, large waves which roll in on a shore, as after a storm. 



RUBBLE. (1) Loose angular waterworn stones along a beach. (2) Rough, 

 irregular fragments of broken rock. 



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 a primary cover layer may be placed 

 in an orderly manner or dumped at random.) 



RUNNEL. A corrugation or trough formed in the foreshore or in the bottom just 

 offshore by waves or tidal currents. 



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

 Also UPRUSH, SWASH. The amount of runup is the vertical height above 

 still-water level to which the rush of water reaches. 



SALTATION. That method of sand movement in a fluid in which individual 

 particles leave the bed by bounding nearly vertically and, because the 

 motion of the fluid is not strong or turbulent enough to retain them in 

 suspension, return to the bed at some distance downstream. The travel 

 path of the particles is a series of hops and bounds. 



SALT MARSH. A marsh periodically flooded by salt water. 



SAND. See SOIL CLASSIFICATION. 



SANDBAR. (1) See BAR. (2) In a river, a ridge of sand built up to or near 

 the surface by river currents. 



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