DEWEES ISLAND 



CAPERS INLET 



CAPERS ISLAND 

 Longshore drift direction 



ATLANTIC OCEAN 



WAVE PEBOO 4.0 SEC 

 DEEPWATER ANGLE 90.0 DEGREES 

 DATE PLOTTED 08/14/78 

 DEEPWATER WAVE HEIGHT ■ 1.0 FT 



CONTOUR AT MLW 



RELATIVE WATER LEVEL-; qoo FT 



MAP DATE. 1921 



Figure 16. Wave refraction diagram showing drift reversal as a result 

 of ebb delta bathymetry (Fico 1978, reprinted by permission) 



and forces landward migration of swash bar complexes that periodically nourish 

 the shoreline. Migrating inlets, which are shallow and not anchored in 

 pre-Holocene material, move under the influence of littoral drift. Typically, 

 southward migration is accompanied by spit elongation on the north side of an 

 inlet. Eventually, the elongated inlet channel becomes inefficient, and a new 

 channel breaches the spit to the north, renewing the cycle. The severed spit 

 generally welds to the downdrift beach. A third type of inlet is one in which 

 the ebb channel, under influence of the littoral drift, is pushed south across 

 the delta until it becomes inefficient. It then cuts a new channel to the 

 north side of the ebb delta, where it again begins its southward migration. 

 Sand along the old southern channel migrates landward and welds to the beach, 



36 



