Figure 5. A recurved spit (center, left) extends Kiawah’s length, formed by the continuous accretion of longshore transported sand.
The Kiawah River flows along the spit’s landward side. Captain Sams Inlet with its small ebb-tidal delta lies between Kiawah and
Seabrook Islands. (Photo by L. Sautter, 2014).
a hooked, or recurved morphology, where the accreting sand
has wrapped around the spit’s end. Over time, the accreted
sand may form dunes and become stabilized by vegetation.
At the beginning of Kiawah’s spit feature can be found the
narrowest section of the island, often referred to as the
“neck,” measuring less than 0.1 mile. The neck is threatened
on its landward side by a large bend in the tidally-influenced
Kiawah River.
As Kiawah’s spit accretes in the downdrift, or southwest
direction, the inlet also migrates southwest, cutting into
the shoreline of Seabrook Island. In the case of Captain
Sams Inlet, migration is an ongoing occurrence. In the
1970s, Walter J. Sexton (Masters Thesis, University of South
Carolina) examined historical charts dating back to 1661 and
documented that both the inlet’s location and spit’s length
have changed dramatically through the years. Not only has
the spit’s growth caused the inlet to migrate downdrift, but
Captain Sams Inlet has on numerous occasions been naturally
relocated to an updrift (i.e., northeast) position by severe
storms and hurricanes. Large storm surges and excessively
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large waves have combined to cause breaching of the spit,
most likely at the neck, its narrowest and most erosion-
vulnerable point.
Once breached, tidal currents are able to flow immediately
into the newly formed channel, thereby maintaining it. The
decreased flow within the old inlet serves to help sediments
infill the channel over time. Following a breach, normal
longshore currents resume and allow the spit to begin
accreting again, along with the gentle but steady migration of
Captain Sams Inlet toward Seabrook Island. A long history of
continual southwestward migration of Captain Sams Inlet and
the narrowness of the spit’s neck make the southwest end of
Kiawah a highly dynamic and vulnerable stretch of shoreline.
The last natural spit breaching and subsequent relocation
of Captain Sams Inlet occurred in the 1940s. In the
decades that followed, Seabrook Resort experienced severe
erosion from inlet migration. In 1983, Research Planning,
Inc. (formerly called Research Planning Institute) was
contracted by Seabrook Island to engineer a breach of the
spit approximately 0.9 miles from the current Charleston
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