1993 as the spit straightened and gained sand. As of 1999, the width of the inlet
was 5,600 ft (1,707 m).
A northern ebb channel formed in early 1995 some 1,000 ft (305 m) north of
the original breach. That northern channel meandered to the north and as of 1999
was 800 ft (244 m) wide. With two ebb channels, and a complex system of shoals
at the mouth of the south ebb channel, the south ebb channel narrowed to approxi-
mately 500 ft (152 m) in July 1999. It is now positioned against the South Beach
shore and presumably will lose its dominance to the north channel. As a single
south ebb channel, it was approximately 600 ft (183 m) wide.
A plot of the channel center lines through time shows the southern migration
of the south ebb channel, with the position becoming fixed in 1994 after the South
Beach became permanently attached to the mainland (Figure 21). The north
channel meandered around after its formation in 1995, but has remained north of
the original breach. Chatham Inlet has evolved into a two-ebb channel system and
the channels have continued to change position within the inlet throat, with the
north channel now taking a more dominant role as the preferred channel.
Mainland Shoreline Segments
With the opening of the inlet, the mainland shoreline went from a low energy,
tidally dominated estuarine condition to an open ocean wave and tide dominated
system. These processes had a profound influence on the morphologic evolution
of the mainland shore, with the beach responding to both cross-shore and long-
shore currents. To describe the highly variable change in the mainland shoreline,
it has been divided into four segments, based on morphology and position relative
to the inlet throat.
Aunt Lydia's Cove
Part of segment 1, north of the Fish Pier extending from Cow Yard Landing
to the Fish Pier has been protected from waves and tidal currents by Tern Island
and the extensive shoals on the north end of Tern Island. This mainland shoreline
in Aunt Lydia's Cove, behind Tern Island has changed little throughout the study
period (Figure 22). The shore is composed of a narrow width of sand and some
marsh. In contrast, south of the Fish Pier the shoreline reach extending to Claflin
Landing has undergone extensive change. This area of the Cove's shoreline has
been influenced by the changes in the south Tern Island shoal and later by
changes in the navigation channel and western ebb spit of the north flood shoal.
South of Claflin Landing, the shoreline experienced erosion and flood tidal cur-
rents have transported some of that sand northward. A spit formed at the southern
point of Aunt Lydia's Cove in 1990 as the sand deposit started to grow north. This
spit progressed to the north in yearly increments until 1996 when the accretion
formed a wide beach in that area. Since 1996 the shoreline has remained in that
position as the Tern Island shoal eroded and the main channel has occupied the
area just off the beach. The town has nourished the beach at Claflin Landing with
an approximate total of 8,000 cu yd (6,117 m3) in May 1998 and May 2000.
35
Chapter 3 Inlet Throat, Shoreline, and Channel Evolution
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