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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
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.
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.
