01/30/2009
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–S&W–DEW [DRAFT]
Accreted Land Management Plan
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2253 [30 JANUARY 2009]
Town of Sullivan’s Island, SC
1.0 INTRODUCTION
The town of Sullivan’s Island includes over 190 acres of accreted beachfront property, placing
it among a handful of barrier islands in South Carolina that have gained sand during the past
century (Hayes 1994, Kana and Gaudiano 2001). Historical shoreline studies dating back to
the 1970s (eg – Stephen et al 1975) attributed the buildup along Sullivan’s Island to Charleston
Harbor jetty construction in the late 1800s. Also, an important factor is a plentiful updrift sand
supply which periodically bypasses from Isle of Palms to Sullivan’s Island by way of Breach
Inlet (Nelligan 1982).
Following its construction a century ago, the Charleston jetty trapped sand before it could pro-
ceed around the south end of the island. Since then, extensive buildup along the front beach
has buried the landward end of the jetty and now allows sand to migrate freely over the weir
section and accrete along the western end of the island. Some sections of the beach have
accreted over 1,500 feet (ft) since the 1940s.
As accreted land (AL) evolves, a succession of vegetation types occurs that are typical of low-
country barrier islands. First to appear are dune grasses and pioneering beach shrubs such
as Iva imbricata (beach elder). Later stages bring species such as Yucca (Spanish bayonet).
Waxed myrtle (Myrica cerifera) is a dominant transition species that generally becomes estab-
lished within ten years after the land has accreted. If the land remains free of tidal flooding,
primary maritime forest species (palmetto, live oak, cedar, magnolia, loblolly pine) become
established. After several decades free from flooding, the maritime forest species grow high
enough to blanket the myrtle and other shrubs, leading to a natural die-off of the understory.
The type of vegetation in the backshore area offers insight regarding the age of the land:
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Grassed areas are usually very young (measured in a few years).
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Waxed myrtle zones are at least one decade old.
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Forested areas are at least several decades old.
As new land has accreted and vegetation has matured, the character and vistas of the beach
front have changed. Views of the ocean have been altered; access has become more difficult;
and new habitats have formed. Some aspects are generally favorable such as increased sep-
aration between development and damaging waves. Other aspects are problematic, such as
blocked views, increased fire hazards, nuisance species, and lowered security along beach-
access paths.