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OCR for page 165
F
Aftermath of Hurricane Hugo
Hurricane Hugo made landfall on September 22, 1989, just north
of Charleston, South Carolina. This Class IV hurricane had sustained
winds to 135 mph and generated a maximum storm surge of 20 feet.
Although storm flooding extended several miles inland, the worst
destruction occurred on the low-lying, sandy barrier islands along
the coast. These islands were essentially under water during the
height of the storm surge (average island elevations are less than
10 feet), and hurricane-forced waves battered the Atlantic Coast
beaches. While field survey data are still being analyzed, the first
indications are that beach recession averaged over 100 feet, with some
profile comparisons indicating 150 feet of beach erosion and complete
dune leveling. The damage to beachfront houses was extensive on
many of the islands near the storm track (e.g., Pawleys, Sullivans,
and Follys islands, S.C.~. It should be noted, however, that the true
erosional potential of this Class IV hurricane was not experienced
because of the rapid forward motion of the storm (24 mph, which is
over twice the normal rate of progression).
The importance of acquiring historical shoreline change and
Dr. Stephen P. Leatherman, a member of this committee and the author of
this appendix, is also a member of the National Research Council's Hurricane
Hugo Post-Storm Assessment Team.
165
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166
APPENDIX F
oceanographic data and applying this information to establish coastal
erosion zones is well illustrated by the relative damage to beachfront
houses in the area affected by the hurricane. The differences in
sustained damage at Isle of Palms (north of Charleston, maximum
average storm surge of 13 feet) and Folly Beach (south of Charleston
and eye of hurricane, maximum average storm surge of 12 feet) was
striking. While there was extensive damage at Isle of Palms due to
inundation of the island, beachfront houses were generally protected
by a wide beach and sand dunes. This storm buffer zone served its
purpose well, with damage concentrated to areas where the beaches
were narrow and dunes small to absent. The building practices at
Isle of Palms were generally consistent with shoreline dynamics, and
most damage was inflicted upon pre-FIRM houses sitting on grade.
Unreinforced concrete block houses were particularly susceptible to
destruction in the V-zone. Often no more than a few blocks of a
whole house could be found still attached after the storm. These
ill-suited houses appeared to have been "blown-out" by the storm
surge and superimposed hurricane-generated waves.
Folly Beach, on the other hand, experienced considerably more
and greater damage despite the fact that it was on the weaker (south)
side of the storm center. The beach at Folly has been subjected to
long-term erosion, so it was already critically narrow before the
storm. Residents had resorted to dumping large stones and concrete
rubble on their beaches to form riprap revetments, so the shore
was heavily armored. These preparations were largely ineffective,
as the high surge allowed the storm waves to overtop these coastal
engineering structures and inflict heavy damage on the beachfront
houses.
The Atlantic House, a local landmark and popular seafood
restaurant on Folly Beach, was completely destroyed by Hurricane
Hugo. Erosion had gradually whittled away the beach, so an elevated
ramp over the water was necessary in order to reach the restaurant.
While the hurricane surely swept away the building, it was the long-
term erosion that set it up for inevitable destruction. This illustrates
the difficulty the general public has in understanding the process (the
gradual, long-term erosion of beaches) and the total emphasis placed
on an event (hurricane) in terms of the resulting damage. Certainly
better data on long-term shoreline changes, public understanding
and acceptance of this information, and the institutionalization of
conformance standards for setbacks need to be given considerable
attention.
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APPENDIX F
167
based on emotional reactions and stop-gap solutions often super-
sede sound judgment. Minions of dollars was spent for emergency
procedures to scrape sand oE the beach to rebuild flattened dunes
without any consideration of sustainability. Perhaps more impor-
tantly, state legislators are now calling for rescission of the South
Carolina Beachfront Management Act or at least a liberal interpre-
tation of its building setback provisions so that beachfront homes
can be rebuilt in their prestorm locations. Certainly this is a diffl-
cult time to enforce regulations that are viewed by property owners
as "taking." The reality is that their property has been physically
eroded away, and any reconstruction must be set back an appropriate
distance based on the long-term erosion rate.
National attention is being focused on South Carolina's recovery
from this devastating coastal storm and on the application of the
Beachfront Management Act. If we learned anything from this storm,
it is that the hard decisions must be made before a catastrophe occurs
and that the public must be aware of the consequences for poststorm
construction. Delineation of an Ozone and implementation of the
new FEMA directives in building setback requirements will go a long
way to relieve the current dilemma and public misunderstandings.
Representative terms from entire chapter:
beachfront houses