(5) North flood shoal - has grown in area and migrated north expanding
from a circular shoal into a more typical flood shoal shape, with a
flood ramp, east and west flood channels, ebb shield, ebb spits, and
spillover lobes.
Analysis Methods
All of these areas have undergone major morphologic change from the
preinlet conditions to their present form. Table 3 gives the area of the shoals and
adjacent spits measured from the areal photography. The visible edge of the shoal
was digitized in ArcView from the rectified and georeferenced aerial photogra-
phy. The shoal edge was identified by the change in gray tones from the light gray
of the shoal to the dark gray of the deeper water. In most cases the annual aerial
photography was quite clear and the shoal boundary was distinct. The digitized
outline of the shoal for each year was entered onto a separate layer and the area
was calculated by ArcView. From the one and only bathymetric survey of the inlet
collected by the SHOALS lidar system in November 1998, the approximate depth
range of the visible shoal edge on the July 1998 aerial photography was deter-
mined to be between 5 and 10 ft (1.5 and 3 m) mllw. The water clarity and tone
quality appeared to be consistent on all yearly photo sets, so it is assumed that this
depth range was digitized on each of the shoal edges. This depth range was
assumed for the ebb shoal/swash platform, north and south flood shoal, south