Fig. 11. Change in depth and transport vectors at hr 99, fair-weather wave

Militello_Kraus-03
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enters the channel, moving around the updrift jetty, and would contribute to tidal bypassing.

The ebb shoal deepens in its central area and shallows on its seaward and northeast flanks.

Transport vectors on the shoal indicate that material bypasses from the central shoal area to the

regions of deposition. Morphology change on the shoal indicates an overall spreading pattern

taking place, as the bathymetry moves toward an equilibrium state with the hydrodynamics.

Fig. 11. Change in depth and transport vectors at hr 99, fair-weather wave

Case 3: Storm Wave

Morphology change and transport vectors at hr 99 from the storm wave simulation are shown

in Fig. 12. Little accretion occurs at the south jetty because the surf zone current forms a rip at

the jetty. Sand then deposits in a deltaic form located southeast of the ebb shoal. Erosion along

the beach north of the north jetty also takes place. Scour holes form at the intersection where the

north jetty meets the beach and in an area centered approximately 500 m north of the jetty (the

jetty is 250 m long). Breaking waves on the ebb shoal transport material to the north and west,

spreading the shoal over a wider area. Material is also transported and deposited inside the south

jetty as a tip shoal. Morphology change on the ebb shoal for the storm waves has a different

pattern than for fair- weather waves, with deposition taking place around most of the perimeter

of the shoal. The fair-weather waves produce a splitting pattern in transport where deposition

takes place on different sides of the shoal. The storm wave produces shoaling in the inlet near

the south jetty and erosion at the north jetty. The fair-weather wave produces erosion at the

south jetty, and a mixed erosion and accretion pattern at the north jetty. These differences at the

inlet entrance and the ebb shoal owe to the different patterns of wave refraction, shoaling, and

breaking on the shoal for the storm and fair-weather waves. Bypassing bars also form up-and

Militello and Kraus