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Inlet Processes, Massachusetts
Figure 4.
Shoreline changes along the barrier south of New Inlet between 1990 and 2000. During the period of record, sand trapping by
the bay, ebb-tidal delta, and updrift spit have reduced the sand supply to the downdrift barrier resulting in severe erosion.
INLET AND EBB-TIDAL DELTA EVOLUTION
across the barrier forming an overwash channel. It was this
diminutive channel that would become proto-New Inlet.
Accounts of the morphological development of New Inlet
The fact that the adjacent Pleasant Bay was wide and
and the ebb tidal delta can be found in LIU et al. (1993) and
relatively deep aided the development of the inlet by
STAUBLE (2001). One of the immediate effects of the
preventing formation of a broad overwash fan which would
breaching was a continuous widening of the inlet over the
have impeded the access of the bay tidal prism. The GIESE
next year and half, which involved the northward and
(1988) model and breaching of a barrier, in general, involve
southward retreat of the inlet shorelines. During this time
numerous factors that must work synergetically before a
much of the eroded barrier sand was washed into the inlet
stable tidal inlet can be formed.
enlarging the flood-tidal delta and other sand shoals
(FITZGERALD and MONTELLO, 1993; PENDLETON
and FITZGERALD, 2001; STAUBLE, 2001). Using the
configuration of the pre-breach shoreline and 1990
bathymetry (FITZGERALD and MONTELLO, 1993), it is
estimated that between 0.7 and 1.0 x 106 m3 of barrier sand
was washed into the bay. Some of this sediment was
Journal of Coastal Research, Special Issue 36, 2002
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