Barrier Island Ecology of Cape Lookout National Seashore and Vicinity, North Carolina
NPS Scientific Monograph No. 9
EFFECTS OF MAN ON THE OUTER BANKS (continued)
Despite the obvious hazards of building too close to
the beach, new hotels, such as the Holiday Inn on Wrightsville Beach
shown in Fig. 106, are being constructed all along the Atlantic
shoreline and are inviting disaster from the next hurricane. After a
short time, the beach retreats and the owners of beach property then
lobby for a publicly funded beach nourishment project (Fig. 107) to
protect their private holdings which, in most cases, should never have
been built there in the first place. Thus starts a never-ending cycle of
erosion and temporary engineering solutions for a situation that will
continue to worsen.
Fig. 106. A resort motel under
construction at Wrightsville Beach, North Carolina. The high tide line
is in the foreground.
Fig. 107. The eroded scarp typical of
beaches artificially built of fine sediment dredged out of the
On the western end of Bogue Banks, acres of prime
maritime forest, festooned with Tillandsia usneoides, were
cleaned off to build a four-lane highway (Fig. 108). Near the middle of
the island, one developer has gone so far as to cut nearly through the
dry land with a channel from the sound side to provide boat access to a
trailer park, thus inviting the formation of a new inlet by the next big
Fig. 108. Road cut through an
outstanding maritime forest on western Bogue Banks.
All these developments must be supplied with water.
Deep wells on the islands produce water that is unpleasantly sulfurous.
Shallow wells sunk into the surface water table result in better water,
but the water table floats as a lens resting on and surrounded by salt
water, and is derived entirely from rainfall. If too much fresh water is
removed, the salt water moves in more or less permanently. This is a
widespread difficulty with coastal water supplies.
That those who use the developments may be spared the
problem of mosquitoes, some of the Outer Banks' salt marshes have been
ditched and, in the past, sprayed. This removes a small amount of the
marsh itself from estuarine productivity, and may have other ecological
effects such as drying out the marsh so that more terrestrial and less
productive species can invade. However, the overall result may not be
entirely negative, since there are suggestions that nutrient exchange
and productivity output may be improved by ditching (Fig. 109).
Fig. 109. Salt marsh mosquito ditches in
eastern North Carolina, The ditches are 6 ft. (1.8 m) wide, very deep,
and built without regard for natural drainage patterns.
Marshes have also been used as a source of beach fill
and barrier dike material, as well as being filled for various
development purposes (Figs. 110 and 111). Such ecologically disastrous
operations should presumably no longer be permitted on Federal lands,
but they are still being carried out at alarming rates on private land,
despite efforts to protect these resources. Dredging and filling of
marshlands have been all too common activities behind the more easily
accessible barrier islands. The size of Cape Lookout, however, has been
greatly increased in recent years, and its shape changed, partly because
of the jetty which was built there in 1915 (Figs. 129 and 130).
Fig. 110. This boat-launching bay was
made by excavating a salt marsh to get fill to shore up an eroding dune
line. Cape Hatteras National Seashore is in the background. The already
vulnerable island has been further narrowed.
Fig. 111. Marsh adjacent to the same bay
is being filled to make a parking lot for the boat launchers. This sort
of thing would presumably not be done today.
The effects of technology and development on barrier
beaches are graphically illustrated when natural beaches are compared to
highly modified ones, where erosion has become a problem and various
techniques are being used to "control" barrier-island retreat. Figure
112 is an aerial view of the still undeveloped Cape Lookout beach
system, where the only major human impact consists of the lighthouse and
a few buildings on the back side of the Cape. Storm tides can sweep
across Cape Lookout but do no real damage, and the beach retreats
according to natural processes. Here beach erosion is not a problem.
Fig. 112. Cape Lookout Lighthouse.
Thirty or forty years ago the Hatteras Lighthouse was separated from the
ocean by a similarly side berm. (Photo by R. Simpson.)
In contrast, Figs. 113 and 114 show several stages in
the degradation of the beach at Cape Hatteras, and consequent attempts
to control erosion. The Cape Hatteras region was once much like Cape
Lookout, with a wide beach and no developments near the beach.
Historically, the section of the Hatteras beach near the lighthouse has
experienced continuous retreat, but when the lighthouse was built in the
mid-1800s, the beach was wide. Over the years the beach has retreated
closer to the lighthouse. The greatest problems came in recent years,
however, following the creation of a "stabilized" dune line on the
beach. Private land was quickly developed with summer houses and motels,
and in addition, a U.S. Navy facility was built just north of the
lighthouse. The man-made dunes did not solve the erosion difficulties,
but they have been increasingly attacked by waves, with obvious threat
to the structures behind.
Fig. 113. (A) In 1969, Cape
Hatteras Lighthouse and the naval facility just beyond were in serious
danger from the sea. The white strip in front of the lighthouse is
plastic bags filled with sand. Note the narrowness of the beach, the
irregularity of its outer edge, and the artificial dunes in the
foreground. (Photo by Cape Hatteras National Seashore.)
(B) The beach after groins were built in 1970. The groins have
captured sand moving down the beach and the lighthouse is temporarily
safe, but note how the artificial dune has been cut away by erosion on
the downdrift side of the groin. (Photo by Cape Hatteras National
Fig. 114. (A) Looking south along
the Hatteras Island beach in 1969. Note motels and private houses just
behind the dune line, (Photo by Cape Hatteras National Seashore.)
(B) The same just after a bad storm in November 1971, cut away
much of the dune line. There has been a breakthrough with overwash; the
waves are very close to the motels; the objects on the beach in the
foreground are the remains of plastic bags filled with sand to hold back
the sea. (Photo by Cape Hatteras National Seashore.) (C)
To remedy the situation in B, an experimental beach nourishment
project was begun in February 1972, with sand pumped from Hatteras
Point. The erosion problem in front of the motels is temporarily
relieved. (Photo by Cape Hatteras National Seashore.)
As the stabilized dunes broke down, various temporary
remedies were initiated, such as placing bags of sand at the toe of the
dune in front of the lighthouse (Fig. 113A). Following the failure of
these attempts, three groins were built opposite the naval facility and
the lighthouse, resulting in predictable changes in the beach system
(Fig. 113B). The groins did indeed stop migration of sand down the beach
from the north and widened the beach, but the downdrift side of the
structures was then starved for sand, and here erosion was greatly
accelerated. Concern was then raised about the historic site of the
former lighthouse, south of the present structure, which was soon
threatened by more rapid erosion, not to mention the general loss of
National Seashore land south of the groins. Thus, while the groins may
have slowed the erosion at the lighthouse, they hastened the loss
farther down the beach and changed the whole shape of the shoreline.
With erosion continuing to the north of the
lighthouse (which soon took on the appearance and exposure of a headland
at sea), and periods of overwash through what remained of the dune into
the developed areas (Figs. 114A and 114B), a plan was devised to
artificially restore the beach. Sand was pumped from an accreting part
of Cape Hatteras south of the lighthouse to the eroding sections on the
north side (Fig. 114C).
This beach "restoration" is another type of
environmental tampering which has both positive and negative aspects.
Dredging fine sediment out of the estuaries and marshes to "nourish" the
beach is purest folly, for the material is so fine that it is soon
washed away in the high energy environment of the beach (Fig. 107). The
beach is "improved" for only a little while, but the sound or marsh from
which the fill was taken is damaged permanently. Clearly, the short-term
benefits obtained by this operation must be weighed against the
longer-term costs of estuarine destruction. Nourishment can be more
useful when normal beach sand is moved from accreting to eroding areas,
thus putting the sand back into the littoral drift (Fig. 114) or by
pumping spoil from inlet dredging onto the downdrift beach. All such
operations are expensive in terms of initial costs, long-term cost, and
hidden ecological cost. They are clearly only temporary solutions, and
must be carefully evaluated as to the value of the structures they are
designed to protect. In many cases it might be cheaper and more
desirable to remove or relocate the threatened buildings than to
continuously rebuild the beach by artificial techniques.
The most practical "use" that can be made of the
Outer Banks is recreation. A great deal of fishing, shellfishing,
hunting, swimming, and just plain enjoying the outdoors has taken place
on both developed and undeveloped islands over the years. There is
nothing intrinsically destructive to the environment about these
activities as long as the participants follow the rules on catch limits,
and if they can enjoy themselves without the help of a lot of
environmentally destructive development. Unfortunately, a good many
people have shown no respect for the Outer Banks environment and have
spoiled a great deal of it for more sensitive visitors. Surf fishing on
Core Banks is a case in point. There are a great many camps on the
island where the fishermen stay; clusters of them are sometimes
surrounded by rings of abandoned cars towed there in an effort to
protect the buildings from the sea (Fig. 115). Fishermen bring to the
island an old car which they drive up and down the beach until it wears
out or gets hopelessly stuck. This in itself does no real harm unless
the car is driven over dune grass or through bird nesting grounds, but
the car is eventually left to rust on the beach, where it is an esthetic
insult and a safety hazard. No one wants to pay to have a valueless
vehicle ferried ashore. There are probably over a thousand such hulks on
Core Banks (Fig. 116). Most builders of cabins are squatting on the
land, since at present most of the land in Cape Lookout National
Seashore is owned by the state of North Carolina. Although some people
have put up neat, decent little buildings, many of the cabins are
unsightly, vermin-infested hovels surrounded by rubbish (Figs. 117 and
118). Such conditions will eventually be remedied by the National Park
Service as it takes control of Cape Lookout National Seashore.
(Esthetics and health considerations aside, the cabins do show that it
is possible to build on the unprotected parts of the islands if one
accepts flooding as inevitable; the camps are built mostly on posts and
the high water simply flows underneath.)
Fig. 115. A typical fishing camp on Core
Banks, with a line of old cars in front to catch sand.
Fig. 116. The cars have started a few
small Uniola dunes, but the unsightly array does not help the
beach nor does it provide real protection from a major storm.
Fig. 117. A representative scene inside
the fishing camp.
Fig. 118. Solid waste and the remains of
a feral cat on Core Banks.
Last Updated: 21-Oct-2005