SHALLOW WATER - (1) Commonly, water of such a depth that surface waves 

 are noticeably affected by bottom topography. It is customary to 

 consider water of depths less than one-half the surface wavelength 

 as shallow water. See DEEP WATER. (2) More strictly, in hydro- 

 dynamics with regard to progressive gravity waves, water in which 

 the depth is less than 1/25 the wavelength. 



SHORE - The narrow strip of land in immediate contact with the sea, 

 including the zone between high and low water lines. A shore of 

 unconsolidated material is usually called a beach. 



SHORELINE - The intersection of a specified plane of water with the shore 

 or beach. (e.g., the highwater shoreline would be the intersection 

 of the plane of mean high water with the shore or beach.) The line 

 delineating the shoreline on U.S. Coast and Geodetic Survey 

 nautical charts and surveys approximates the mean high water line. 



SLIP - A berthing space between two piers. 



SOUNDING - A measured depth of water. On hydrographic charts the 



soundings are adjusted to a specific plane of reference (Sounding 

 Datum) . 



SOUNDING LINE - A line, wire, or cord used in sounding. It is weighted 

 at one end with a plummet (sounding lead). Also LEADLINE. 



SPIT - Small point of land or a narrow shoal projecting into a body of 

 water from the shore. 



STILLWATER LEVEL - The elevation that the surface of the water would 

 assume if all wave action were absent. 



SURF - The wave activity in the area between the shoreline and the 

 outermost limit of breakers. 



SURF ZONE - The area between the outermost breaker and the limit of 

 wave uprush. 



TOMBOLO - A bar or spit that connects or "ties" an island to the 

 mainland or to another island. 



UPDRIFT - The direction opposite that of the predominant movement of 

 littoral materials. 



UPRUSH - The rush of water up onto the beach following the breaking of 

 a wave. Also Swash, RUNUP. 



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