Executive Summary

INTRODUCTION

Hurricane Hugo, which caused approximately $10 billion in damage, had been the costliest hurricane to strike the United States before Andrew three years later in 1992. Hugo was, in some ways, two hurricanes in one. From September 17 through 18, 1989, it passed through the U.S. Virgin Islands and Puerto Rico, leaving $3 billion in damage in its wake. After leaving the islands, Hugo remained over the waters of the Atlantic for over 3 days, gaining in strength and size until it made its assault on the South Carolina coast near Charleston minutes before midnight on September 22. Even after making landfall, Hugo remained a threat and caused damage over 200 miles inland, and its effects were felt beyond Charlotte, North Carolina.

Some common threads run through Hugo's story from the Caribbean to the Carolinas, such as the lack of surface-wind-speed data, the prediction capability of the Sea, Lake, and Overland Surges from Hurricanes (SLOSH) model, and the poor performance of school buildings in high winds. However, the many significant differences between the Caribbean Islands and the Carolinas pointed to the need for two study teams to perform reconnaissance studies after Hugo.

This report for the Committee on Natural Disasters (CND) is unique in that it is two reports in one. The first section covers the U.S. Virgin Islands and Puerto Rico, and the second section reports on the Carolinas.

The report also affords a unique opportunity for comparison of emergency preparation and response efforts and the extent of property damage between mainland states and a commonwealth, one-language and two-language cultures, and island and mainland coastlines. The format of this report allows the reader to focus on one region at a time so that in-depth study and analysis on a particular area can be readily made.



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HURRICANE HUGO: PUERTO RICO, THE U.S. VIRGIN ISLANDS, AND SOUTH CAROLINA Executive Summary INTRODUCTION Hurricane Hugo, which caused approximately $10 billion in damage, had been the costliest hurricane to strike the United States before Andrew three years later in 1992. Hugo was, in some ways, two hurricanes in one. From September 17 through 18, 1989, it passed through the U.S. Virgin Islands and Puerto Rico, leaving $3 billion in damage in its wake. After leaving the islands, Hugo remained over the waters of the Atlantic for over 3 days, gaining in strength and size until it made its assault on the South Carolina coast near Charleston minutes before midnight on September 22. Even after making landfall, Hugo remained a threat and caused damage over 200 miles inland, and its effects were felt beyond Charlotte, North Carolina. Some common threads run through Hugo's story from the Caribbean to the Carolinas, such as the lack of surface-wind-speed data, the prediction capability of the Sea, Lake, and Overland Surges from Hurricanes (SLOSH) model, and the poor performance of school buildings in high winds. However, the many significant differences between the Caribbean Islands and the Carolinas pointed to the need for two study teams to perform reconnaissance studies after Hugo. This report for the Committee on Natural Disasters (CND) is unique in that it is two reports in one. The first section covers the U.S. Virgin Islands and Puerto Rico, and the second section reports on the Carolinas. The report also affords a unique opportunity for comparison of emergency preparation and response efforts and the extent of property damage between mainland states and a commonwealth, one-language and two-language cultures, and island and mainland coastlines. The format of this report allows the reader to focus on one region at a time so that in-depth study and analysis on a particular area can be readily made.

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HURRICANE HUGO: PUERTO RICO, THE U.S. VIRGIN ISLANDS, AND SOUTH CAROLINA THE U.S. VIRGIN ISLANDS AND PUERTO RICO: SEPTEMBER 17-18, 1989 Meteorology/Storm History Hurricane Hugo began as a tropical disturbance off the west African coast on September 9, 1989. It belongs to the class of hurricanes termed Cape Verde storms. Hugo gained intensity while crossing the Atlantic, and by September 13 it had reached full hurricane status, with a wind speed in excess of 64 knots (74 mph). Hugo affected several islands in the Caribbean, including Guadeloupe and Montserrat, the U.S. Virgin Islands of St. Croix and St. Thomas, and Puerto Rico. Before reaching the islands, sustained wind speeds of 165 knots (190 mph) were measured at 1,500 ft altitude, qualifying Hugo as a category 5 hurricane on the Saffir-Simpson scale. Category 5 is the most intense category included on the scale. Equally notable, Hugo's central pressure in the eye hit a low of 27.1 inches (918 millibars [mb]), a tie for the record minimum pressure in the Atlantic. Hugo was a category 4 hurricane when it crossed the Caribbean islands. On Guadeloupe, about half of the capital city of Pointe-a-Pitre was destroyed. Severe damage also occurred on the nearby island of Montserrat. The U.S. Virgin Islands of St. Croix and St. Thomas were hard hit, with St. Croix experiencing an unusually prolonged battering of hurricane-force winds. Hugo crossed over St. Croix the evening of September 17 through the early morning of the 18th. Hugo then passed through Vieques Sound, between the islands of Culebra and Vieques, early on September 18 and moved over Puerto Rico around 0830 AST. After subjecting northeastern Puerto Rico to hurricane-force winds and rains and causing extensive damage, particularly in the San Juan area, Hugo was again over open water, heading for the mainland. Warnings/Evacuations/Emergency Response On Friday, September 15, at 2100 AST, a hurricane watch was issued by the National Weather Service (NWS) Office in San Juan, Puerto Rico; by 1515 AST on September 16, a hurricane warning was declared. As a result, Puerto Rico's Civil Defense Office activated the island 's Disaster Interagency Committee and began to evacuate coastal residents. Information about Hugo's approach, imminent extreme weather conditions, and evacuation preparedness was disseminated effectively by the mass media. Through the use of daily newspapers and radio and television broadcasts, the public was alerted to the approaching danger of Hurricane Hugo. San Juan and other municipalities in the area made use of the SLOSH “decision-arc” methodology to plan evacuation times and routes for areas threatened by Hugo. The SLOSH model proved to be very useful, particularly for conveying

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HURRICANE HUGO: PUERTO RICO, THE U.S. VIRGIN ISLANDS, AND SOUTH CAROLINA information to municipal authorities in a form that could be utilized effectively in the emergency decision-making process. Related Deaths Although Hurricane Hugo was one of the strongest storms to hit Puerto Rico and the Virgin Islands, there were surprisingly few storm-related deaths. Five fatalities in the U.S. Virgin Islands and Puerto Rico were directly related to Hugo. In addition, the American Red Cross Disaster Services reported 29 hurricane-related (indirect) deaths: 22 on Puerto Rico, 5 on St. Croix, and 1 each on St. Thomas and St. John. Most of the deaths were either drownings or electrocutions. Damages Before Hurricane Andrew in 1992, Hugo was the costliest hurricane endured by the United States. Monetary losses were over $10 billion, with about $3 billion of this damage in the Caribbean. St. Croix and St. Thomas suffered tremendous damage, as did the northeastern corner of Puerto Rico. San Juan, Fajardo, and Luquillo were hard hit, with Luquillo receiving the most severe damage. Hugo's most damaging winds and heaviest rainbands were located in its northeast quadrant, and damage on the Caribbean islands reflects this pattern. Damage to buildings ranged from superficial to total devastation. Many roofs were damaged or destroyed, and nonstructural elements such as doors, windows, and cladding also suffered extensive damage. Single-story concrete buildings weathered the storm well, with minimal damage. Several important lifeline systems were disrupted or damaged during Hurricane Hugo. Electrical distribution lines were particularly hard hit. Lack of electricity, in turn, caused problems in other lifeline systems, specifically for pumping water and transmitting broadcasts via radio and television. In many cases, telephone lines were out as a result of downed poles, often the same poles used for the electrical distribution system. The telephone system was heavily damaged in the Virgin Islands, where service was not restored until December or, in some cases, as late as March 1990. Serious water shortages were experienced in Puerto Rico and especially the Virgin Islands. On St. Croix, a fuel oil tank ruptured, causing nearby water facilities to shut down. Also on St. Croix, a tank supplying most of the island's potable water was knocked out of service by the storm. Water services in the San Juan area were disrupted for 9 days by the overtopping of the El Carraizo Dam. Electric motors in its pumping plant were flooded, leaving them inoperable. Tank trucks were used temporarily to distribute water from elsewhere on Puerto Rico.

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HURRICANE HUGO: PUERTO RICO, THE U.S. VIRGIN ISLANDS, AND SOUTH CAROLINA Physical Processes The shorelines of Puerto Rico and the Virgin Islands are composed of both rocky, steep coasts and sandy beaches. Direct-wave attack and storm-wave overwash were the principal forces of erosion impacting these coasts. Because of the steep, rocky nature of much of the shoreline, the storm surge from Hugo did not have as great an effect in the Caribbean as it did in the Carolinas. In a few areas, however, the storm surge was high enough to ground a large ferry and many boats. Overwash sand covered some shorefront roads, impeding traffic flow after Hugo's passage. As with most hurricanes, many beaches suffered extensive erosion. This is particularly hazardous, since it “sets up” the coastline for further erosion from winter storms following the hurricane season. In addition, considerable damage was inflicted on coastal developments, especially seawalls, paved roads, sidewalks, and many small structures. Since Hugo was a relatively “dry” hurricane, flooding and landslides were not major problems. Some localized flooding did occur, but only in low-lying areas that experience flooding fairly regularly. Landslides were relatively insignificant and were generally associated with exposed roadcuts. Conclusions and Recommendations Hurricane Models The revised NHC83 dynamical/statistical model of the National Hurricane Center (NHC) produced the best forecast tracks for Hurricane Hugo out to 48 hours. However, more time, effort, and support need to be given to the development of a consistent hurricane-prediction model. Currently, no models are available to predict hurricane intensity changes. These changes can be crucial for the prediction of where the most severe damage will occur, and they are also important in the determination of evacuation times and areas to be evacuated. Wind-Speed Data Surface-wind-speed data for Hugo were very sparse in the Caribbean. The U.S. Virgin Islands did not obtain a single verifiable record of surface-wind speed. The only verifiable surface-wind-speed measurements were obtained in Puerto Rico at San Juan International Airport and Roosevelt Roads Naval Station. There must be a reinvigoration of the surface observing network in the Caribbean islands. Rugged wind/pressure instrumentation is available at a moderate cost and could significantly increase the quantity and quality of data recorded during the next hurricane to strike the islands. It is also imperative that the National Oceanic and Atmospheric Administration (NOAA) and the U.S. Air Force (USAF)

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HURRICANE HUGO: PUERTO RICO, THE U.S. VIRGIN ISLANDS, AND SOUTH CAROLINA continue to provide coordinated aerial reconnaissance and monitoring of Atlantic hurricanes so that critical data can be relayed back to National Hurricane Center (NHC) forecasters in real time. Informing Local Media Accurate wind-speed data should be reported to the local media so that speculation and overestimates are avoided. At the beginning of the hurricane season, reporters and journalists should be informed about the nature of wind and its effects on buildings and other structures. Overestimating surface-wind speeds by the media can contribute to a false sense of security about the wind forces that structures can withstand. It can also lead to the gross overdesigning of structures, an unnecessary and expensive practice that can be avoided. Design Criteria Single-family homes suffered the most severe damage from Hugo in the Caribbean. Many homes were built without regard to existing code requirements, and “do-it-yourself” types of wood construction suffered very extensive damage. A concerted technology-transfer effort is needed among federal, Puerto Rican, and U.S. Virgin Islands governments to provide state-of-the-art, economical design criteria for low-income housing in areas affected by Hurricane Hugo. Emergency Power Supply A major problem occurred when the workers at El Carraizo Dam, which provides the main water supply for the city of San Juan, were unable to open its floodgates. Because no backup motors were available, the water stored in its reservoirs was inaccessible to the people of San Juan for 9 days. Dams in hurricane-prone areas must be properly maintained, with provisions for backup motors made in advance. Known weaknesses in the maintenance of E1 Carraizo Dam were documented over 5 years before Hugo struck. Clear lines of responsibility for the El Carraizo Dam must be established in the Commonwealth of Puerto Rico so that a more catastrophic event is not encountered there in the future. ALERT Rain Gage Network The hydrology of Hurricane Hugo was well defined over Puerto Rico, where conventional rain gages were supplemented with data from a special Automated Local Evaluation in Real Time (ALERT) network. In the Virgin Islands,

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HURRICANE HUGO: PUERTO RICO, THE U.S. VIRGIN ISLANDS, AND SOUTH CAROLINA precipitation data were sparse because of the lack of ALERT rain gages and the inability of conventional rain gages to withstand the severe winds of Hugo. More stable rain gage mounts capable of sustaining heavy winds are needed in areas susceptible to hurricanes. In addition, an updated ALERT rain gage network should be extended throughout the U.S. Virgin Islands and Puerto Rico in order to record hurricane and flash-flood precipitation data. This is particularly recommended for areas prone to flash flooding. Emergency Broadcasts The Emergency Broadcast System (EBS) network of stations needs to be extended throughout the U.S. Virgin Islands and Puerto Rico. The EBS, along with the new NOAA Weather Wire, should be expanded to cover the entire Caribbean region. This will allow satellite communications of hurricane and other severe weather information to be obtained in a timely manner. Evacuation Efforts and Shelters Evacuation efforts by civil defense authorities before and during Hugo were successful. The SLOSH model was effectively utilized in the systematic planning of evacuation routes and timing. Unfortunately, several problems were encountered with shelters. During the evacuation many shelters did not open on time or lacked staff and adequate provisions, such as cooking facilities and water. There was also a notable failure of bureaucratic cooperation and coordination throughout the sheltering process. Another problem was the disruption of the school year as a result of schools being used as shelters for too long after Hugo. The ability of shelters in Puerto Rico to accommodate displaced persons throughout various emergency situations must be assessed. Particularly important are the structural soundness and flooding potential of buildings designated as shelters, especially schools. Coastal Zone Management Beaches along the coasts of Puerto Rico and the U.S. Virgin Islands are decreasing in size because of erosion from storms such as Hugo and also because of rises in sea level. Seawalls generally have led to accelerated shoreline erosion rather than preservation, and beaches in front of walls have largely disappeared. Action must be taken to save recreational beaches. Buildings must be moved back, or beach-replenishment programs must be established. Proper setback of coastal buildings and developments is the most practical and economical measure that can be taken to preserve beaches.

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HURRICANE HUGO: PUERTO RICO, THE U.S. VIRGIN ISLANDS, AND SOUTH CAROLINA SOUTH CAROLINA: SEPTEMBER 19-22, 1989 Meteorology After passage through the Caribbean, Hurricane Hugo weakened from a category 4 storm to a category 2 on the Saffir-Simpson scale. As Hugo continued to move northwest toward the U.S. mainland, it slowly gained strength, accelerating and intensifying rapidly back to category 4 status just 10 hours before landfall. Minutes before midnight on September 21, Hugo made landfall near Charleston, South Carolina. Hugo's peak-measured wind gust in South Carolina of 119 knots (137 mph) was recorded by the 36-m (118-ft) anemometer at the North Charleston Navy Yard minutes before Hugo made landfall. After landfall, a maximum sustained surface-wind speed of 76 knots (87 mph) was measured at the Charleston Customs House. In the Bulls Bay area northeast of Charleston, where the storm surge exceeded 20 ft, the sustained surface-wind speed was estimated to be 105 knots (121 mph), based on a reconstruction of the surface windfield after landfall. Three hours after landfall, Hugo's maximum wind speeds were below hurricane force in the vicinity of Columbia and Sumter, South Carolina. Hugo reached Charlotte, North Carolina, 6 hours after landfall with tropical storm force winds of 47 knots (54 mph) at the surface accompanied by gusts up to 76 knots (87 mph). Ground and air surveys and meteorological reports indicate that no tornadoes were generated during Hurricane Hugo. However, Hugo maintained a rapid northward motion after coming onto the mainland and caused extensive damage from South Carolina to well beyond Charlotte, North Carolina, over 200 miles inland. Warnings and Evacuations On Wednesday, September 18, as Hugo headed for the mainland, a hurricane watch was issued for the region from St. Augustine, Florida, to Cape Hatteras, North Carolina. Thursday morning, the watch remained in effect, with a 30 percent probability that Hugo would hit Charleston. At 0600 on September 19, with Hugo's arrival imminent, the NHC issued a hurricane warning extending from Fernandina Beach, Florida, to Cape Lookout, North Carolina. The governor of South Carolina ordered the evacuation of barrier islands, beaches, and peninsulas on September 19, and Charleston County officials ordered the evacuation of Charleston residents on the same day. Most evacuation plans assumed Hugo would hit the mainland as a category 3 storm. However, as Hugo came closer to the coast, it intensified and eventually made landfall as a category 4 storm. Because of this sudden increase in intensity, evacuees in at least one Myrtle Beach, South Carolina, shelter had to be relocated farther inland.

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HURRICANE HUGO: PUERTO RICO, THE U.S. VIRGIN ISLANDS, AND SOUTH CAROLINA Few evacuees went to public shelters. More people went to motels than shelters, and the majority of the evacuees went to the homes of family or friends. Shelter use was most prevalent among low-income households. Overall, the evacuation process proceeded as smoothly as anticipated. In some areas, such as Beaufort and Charleston, residents were discouraged from using public shelters because of concern over the number of people the shelters in these areas were equipped to handle. Before and during Hugo, South Carolina coastal officials relied heavily on the Charleston office of the NWS for advice and input regarding emergency decisions. Surge-inundation maps generated by the SLOSH model were used extensively and were valid in most locations. Coastal Processes Shoreline erosion from Hurricane Hugo's storm surge was experienced along much of South Carolina's low-lying coastal area and barrier islands. The tide gage at Charleston recorded a maximum surge of 12.9 ft. Fortunately, the highest storm surge (20 ft) occurred to the north of the storm path, in the largely undeveloped Bulls Bay area. The average elevation in coastal South Carolina is about 10 ft above mean sea level (MSL). Outer barrier islands generally have lower elevations, averaging around 5 feet, so most of the barrier surface was totally under water during the height of the storm surge. At Pawleys Island, damage was catastrophic where a temporary inlet was cut through the barrier. In the 18-ft storm surge, houses were floated from Pawleys Island across the marsh and onto the mainland. Beaches suffered intense erosion, particularly on the barrier islands. Areas with wide beaches and dunes were more protected from Hugo' s impact, since the beaches acted as buffer zones against Hugo's high winds and storm surge. Narrow beaches with a history of erosion, such as Folly Beach, were most heavily affected by Hugo. Coastal developments in locations with little beach suffered severe damage, despite efforts by residents to fortify the coastline with large stones and concrete rubble piled along the shore as a makeshift revetment. Related Deaths In South Carolina 27 deaths were attributed to Hurricane Hugo, about half of which occurred during the storm. There were seven wind-related deaths and six water/boating fatalities. The 14 deaths not occurring during the storm itself were primarily from cleanup accidents and open flames being used for light.

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HURRICANE HUGO: PUERTO RICO, THE U.S. VIRGIN ISLANDS, AND SOUTH CAROLINA Damage to Buildings and Structures In the Carolinas, property losses from Hurricane Hugo are estimated at about $7 billion. Hugo inflicted severe water damage on coastal structures. Wind damage was observed along the coast from Edisto Beach, South Carolina, to the North Carolina border and inland to beyond Charlotte, North Carolina. Along the coastline, most of the well-engineered and well-built structures sustained very little damage. In contrast, appurtenant structures such as decks, access ladders, and ramps significantly contributed to the damage, since most were not built to resist water forces. Elevation was the main prerequisite for structures to escape severe water damage in the coastal zone. Deep piles, at least 9 inches in diameter, were the only type of foundation to perform well consistently. Scouring behind seawalls due to overtopping was common, and most piers sustained severe damage or were totally destroyed. Poorly designed revetments performed marginally, sometimes retarding erosion, but more commonly contributing to local damage as their armor units became “missiles,” hitting nearby buildings. Jetties and groins suffered little damage during the storm. Wind damage occurred both inland and along the coast. Foundation failures due to wind were common, particularly in flood-prone coastal areas where structures were elevated on unreinforced masonry piers. Where the fastest-mile wind speed exceeded 74 knots (85 mph), major structural damage, including loss of roof structure, collapse of single-story masonry buildings, and complete destruction of mobile homes, occurred along with extensive damage to wood-framed construction and preengineered metal buildings. Wind damage varied according to the amount of exposure, with sheltered areas receiving little or no damage and exposed areas suffering heavy losses. Falling trees caused the majority of the damage in inland areas. Damage to Lifelines The most critical lifeline damaged by Hurricane Hugo in the Carolinas was the electrical power supply system. Between 1 million and 1.5 million customers were without electrical power for at least 2 to 3 weeks. Damage to the electric power system adversely affected the operation of other important lifelines, such as transportation and communications systems and water and wastewater facilities. Hugo interfered with transportation in the Carolinas, but caused only minor structural damage to mainland roads and bridges. Traffic was impeded by debris blocking the roadways and by destruction of traffic signals and signs. On the barrier islands, some roadways were completely washed out. In addition, the failure of the Ben Sawyer Bridge, which provides access to Sullivans Island and the Isle of Palms, severely hampered the recovery effort on those islands. Airports from Charleston to as far north as Hickory, North Carolina, were affected by Hugo. The Charleston

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HURRICANE HUGO: PUERTO RICO, THE U.S. VIRGIN ISLANDS, AND SOUTH CAROLINA airport was closed to commercial traffic for a week after the storm because of damages to airport facilities and lack of off-site electrical power. Telephone systems performed well during and after Hugo, primarily because 80 percent of the lines are underground. Radio and television service was disrupted at both the transmitting and receiving ends by loss of power. Several transmitting towers were also downed by Hugo. Water and wastewater systems were affected primarily by loss of off-site power. Remote lift stations in the wastewater system were without power for extended periods, and some isolated cases of sewage overflow occurred before portable generators were installed. On several barrier islands, severe beach erosion destroyed water and sewer lines and exposed septic tanks. Damage to Cultural Property It is estimated that between 4,000 and 5,000 historic buildings in South Carolina were damaged by Hugo. In addition to the high winds and storm surge during Hugo, rains following the hurricane's passage caused severe water damage to buildings with wind-damaged roofs. Many chimneys and architectural details were lost, and damage to porches and porticos was common. More subtle forms of damage also surfaced in the form of shear cracks in masonry walls, mechanical and fungal damage to plaster, and salt attack on masonry. The Poe branch of the Charleston County Library System, located on Sullivans Island, lost most of its collection of 10,000 books. In addition, the West Ashley branch, the largest in the system, lost approximately 10,000 of its 50,000 books through the rupture of a sewer line. The Confederate Museum building in Charleston suffered structural damage, and its collections were subsequently water-damaged. Most museums, however, received only minor damage during Hugo. Conclusions and Recommendations Forecast Uncertainty The current state of the art in hurricane track and intensity prediction is such that coastal and inland regions must initiate storm preparations 36 to 40 hours prior to forecasted landfall. Hugo's rapid acceleration and subsequent track well inland was not detected until landfall, which caused problems for warning inland communities and implementing emergency procedures. This points to the need for improved track forecasts and intensity-prediction methods. Officials responsible for making emergency decisions need to be aware of forecast uncertainties. There should be an integration of forecast uncertainties into storm-risk assessment so that necessary precautions may be taken in the inland

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HURRICANE HUGO: PUERTO RICO, THE U.S. VIRGIN ISLANDS, AND SOUTH CAROLINA communities that lie within the error margin of postlandfall hurricane-track forecasts. When necessary, technical assistance should be given to emergency-response officials so that the implications of forecast uncertainties are more clearly understood. Wind-Speed Measurement Surface-wind-speed measurements are required to improve warning and forecast capabilities, study the physical processes associated with hurricane decay, and develop design criteria. Automatic surface-observation networks should be expanded and standardized in accordance with World Meteorological Organization (WMO) recommendations (10-min average at 10-m elevation in open exposure, along with peak gust over the averaging period). In addition, research on the development of NEXRAD (Next-Generation Weather Radar) algorithms for the assessment of near-surface hurricane windfields should be supported. Storm-Surge Maps Storm-surge maps, particularly those generated by the SLOSH model, were useful tools for decision makers during Hugo. However, scales no smaller than 1 inch to 2,000 ft should be employed so that detailed determination of the limits of surge-prone areas can be performed. Coastal Zone Management Studies of long-term erosion rates and other data about shoreline evolution are needed as a firm basis for assessing danger-prone areas along the coast. In accordance with the South Carolina Beachfront Management Act, setbacks for coastal buildings and structures should be enforced. Also, some level of compensation should be available to property owners that are not allowed to rebuild after coastal houses and buildings have been severely damaged and destroyed, perhaps based on the fair market value for the proportion of the remaining upland. Since beaches are an important source of revenue for the tourism industry, wise management of the coastal zone is vital. If the beaches are to remain an important attraction for tourists, steps must be taken to preserve them and minimize the effects of the encroaching developments along the coastline. Schools as Shelters During Hurricane Hugo, there was a problem with a school shelter in McClellanville, South Carolina, becoming flooded because of a 10-ft discrepancy

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HURRICANE HUGO: PUERTO RICO, THE U.S. VIRGIN ISLANDS, AND SOUTH CAROLINA between its recorded and actual elevations. This prompted some to recommend that all proposed shelter sites be professionally surveyed; however, this is not necessary. A cost-effective solution to the problem is to superimpose large-scale maps showing shelter locations onto maps showing inundation zones. If specific concerns are raised by these comparisons, on-site surveys may be selectively conducted. Vulnerability of Vital Buildings to Wind Damage Often buildings that must continue to function during storms, including hospitals, emergency operations centers, and public shelters, are vulnerable to wind damage. Most schools used as shelters are not properly designed to withstand the high winds and gusts from hurricanes. Communities should have a qualified wind engineer inspect proposed shelters, hospitals, and other critical facilities to determine their safety. If they are not capable of resisting hurricane-force wind loads, other shelters should be sought or strengthening measures employed. Lifeline Protection and Backup Power To protect electrical lines from wind damage and provide a more consistent power supply to lifelines during emergencies, aboveground electrical lines to hospitals, water and wastewater treatment plants, wastewater lift stations, and communication facilities should be replaced with underground lines. In some of these cases, there may be an additional need to install or upgrade on-site backup generators as well. Emergency Equipment Regional pools of emergency equipment should be established along with a plan for postdisaster distribution and allocation. Equipment should include portable generators, chain saws, and trucks for debris removal. Also, the compatibility of emergency portable generators should be ensured by standardizing connections. Education and Training about Hurricane-Resistant Construction Educational and advisory programs should be developed so that the construction industry can benefit from wind engineering knowledge. Owners, insurers, and mortgagees should be included in these programs so that they can understand the risks and costs associated with certain forms of construction and make informed decisions. Also, building inspectors should participate in training and certification

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HURRICANE HUGO: PUERTO RICO, THE U.S. VIRGIN ISLANDS, AND SOUTH CAROLINA programs on hurricane-resistant construction practices so that they are prepared to enforce wind-related building codes. Evacuation from High-Risk Structures When a hurricane is approaching an area, people should be evacuated from certain types of buildings and structures even if there is no immediate threat of flooding. During Hurricane Hugo, people were instructed to evacuate mobile homes whether or not they were subject to flooding. Many lives were probably saved because of this action. Evacuation had previously been ordered only from areas prone to flooding. In future storms, evacuation should also be ordered from other structures that are likewise vulnerable to wind damage, especially nonengineered and preengineered. Storm Insurance The National Flood Insurance Program (NFIP) needs to recognize that high winds and flooding are not independent in coastal regions. Raising mobile homes 8 to 10 ft on masonry piers to comply with flood insurance requirements transforms a relatively low flood risk into a very high wind risk. To avoid this, comprehensive storm insurance, with provisions for both flooding and wind hazards, should be developed. This comprehensive disaster insurance could effectively simplify claims where buildings are subjected to both wind and flood action. Protection of Historic Properties Especially in areas with many historical buildings and properties, the Federal Emergency Management Agency (FEMA) should extend its organizational network to include those branches of the National Park Service concerned with historic properties, as well as state and local historic preservation societies. Recovery Planning Hurricane evacuation planning generally far exceeded recovery planning in the areas affected by Hugo. Increased recovery planning is needed to reduce the length of postdisaster recovery periods. FEMA should prepare a document to guide communities in making recovery plans.

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HURRICANE HUGO: PUERTO RICO, THE U.S. VIRGIN ISLANDS, AND SOUTH CAROLINA State Responsibility Few states appear to feel any financial obligation to provide disaster assistance to their citizens. Instead, they leave the task to the federal government and volunteer organizations. However, when the magnitude of a disaster's effects is not sufficient for a community to qualify for federal assistance, large financial hardships result. Over-federalization of disaster assistance can lead to inequitable cross-subsidies, especially since communities and states have varying degrees of per capita exposure to disaster losses. The role and responsibility of state governments in disaster assistance needs to be examined, including means of funding state programs.

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HURRICANE HUGO: PUERTO RICO, THE U.S. VIRGIN ISLANDS, AND SOUTH CAROLINA Hurricane Hugo, September 17-18, 1989: Puerto Rico and the U.S. Virgin Islands