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 **In 1954 Hurricane Hazel raked the coast of the Carolinas; a storm not unlike the hundreds of hurricanes through the centuries, but she left a path of over $280 million in destruction (fig 1.1). In 1965, Hurricane Betsy became the first .gif) hurricane to exceed one billion dollars in total damages, mostly in Florida and Louisiana (fig 1.2); and in 1969 Hurricane Camille killed 256 along the Gulf Coast and slightly exceeded Betsy in damages, accounting for over $1.4 billion of property loss. Ten years later Hurricane Frederic ran up a $2.3 billion bill in losses along much of the same Mississippi-Alabama coast (fig 1.3). That record stood until 1989 when Nature's forces turned again on the Carolinas and Hurricane Hugo left a wake of widespread destruction along the coast as well as inland to the tune of $7 billion. And the cost more than tripled again in 1992 when Hurricane Andrew's visit to Florida and Louisiana destroyed or damaged property worth about $25,000,000,000 (table 1.1). Since then, Opal, Fran, and Floyd have all left their mark. The ten costliest hurricanes of the 20th century came after 1964. Is each successive hurricane getting bigger; more severe in wind velocity, wave energy, and associated flooding?
 ***Hurricanes are not the only big events in the spotlight. Winter northeaster's expend their energy over great stretches of the Atlantic coast and wave erosion associated with extratropical storms is not uncommon on the Gulf shores as well. The Ash Wednesday storm of 1962 affected nearly the entire U. S. Atlantic Coast causing over $300 million in property damage and changing the shape of the shore in terms of beach and dune erosion, opening new inlets, and burying roads and property under overwash sand (fig 1.4). Extensive overwash was again the case in North Carolina during the 1972 Lincoln's Birthday storm. The Halloween storm of 1991 was described as one of the greatest northeaster's in 50 years, but just two years later, a 1993 northeaster was dubbed the "Storm of the Century"! Are hurricanes and big winter storms becoming more frequent?
**No matter how we measure the impact, whether in number of buildings destroyed, lives lost, people temporarily displaced, or the billions of dollars in losses, we have to wonder "What is happening?" and "Who is paying the bill for all of these losses?".
Although there are suggestions that storm frequency and intensity do vary with global climatic changes, today's spiraling losses are not being caused by bigger hurricanes. Hurricanes Andrew and Hugo were not as powerful as Hurricane Camille; yet their financial impacts were far greater. Hurricane Agnes (1972) was a lightweight, but is fourth on the all-time damage list (see table 1.1). On the other hand, the work of Davis and Dolan (1993) suggests that the in the past decade there have been fewer northeasters, but more big ones, compared to the last 50 years of record. If the latter is a long-term trend, what are the implications for development in the coastal zone?
What has changed most significantly since the 1950s is the dramatic, rapid population increase in the coastal zone. The associated density of development is in an area that is far more vulnerable than inland areas to being impacted by natural processes such as wind, waves, storm- surge flooding, coastal erosion, and related processes.
**In regard to who is paying the ever increasing costs for these events, and the day-to-day losses in "little" events that go unreported, the answer is "we are all paying" and in a variety of ways. The individual property owner suffers the obvious loss; their neighbors and community maintain the streets and services that must be repaired and replaced; the county and state taxpayers share the burden of such costs; every federal taxpayer (even those far removed from the shore) also contributes through underwriting disaster assistance, the national flood insurance program, loans to communities to build and replace the infrastructure of services, loans to businesses, loans to veterans, temporary housing for those who are displaced, and the list of "donuts for disaster victims" goes on. Taxpayers at all levels support the federal portion of costs for U. S. Army Corps of Engineers projects to rebuild beaches, and to construct the coastal defenses such as seawalls that protect property at the cost of beach loss (a public resource). When we pay "tourist" taxes--the motel fee, the beach-user's tag, the community sales tax--we contribute to the maintenance of the seawall or the next truck load of sand purchased for the town beach.
If you purchase or own property insurance, especially flood insurance, or own stock in an insurance company, you will share the cost of coastal property losses. Insurance companies with home offices outside of the storm area, for example, in Connecticut or Michigan will take the financial hit from the resulting claims from damaged buildings in Texas or wind-ripped mobile homes in Florida. Hurricane Andrew caused the demise of nine Florida-based insurance companies, and caused several more to withdraw or reduce their exposure in Florida. Ownership in any business closed down or lost in a storm is ownership in the loss. Surviving building suppliers and ice plants do a land-office business in the aftermath.
**All of us pay in one way or another for the studies, plans, and projects to restore, maintain, and protect these high risk coastal communities. We as residents, recreational users, taxpayers, investors, insurance customers, and so on are the underwriters of coastal development, coastal land use, and mitigation against coastal hazards. We are contributing to a giant welfare system in which high-risk development is encouraged and then rewarded when disaster strikes!
Coastal Population Bomb
 **Despite the all too real potential for coastal catastrophe, the USA's population is migrating toward the coast at a rapid rate. In recent decades, areas within five miles of the shoreline have experienced population growth rates three times the national average. Unfortunately, the demand for ocean views and private beach access encourages development in extreme-risk, beachfront areas, placing ever increasing property investments, and more and more residents at high risk to the impacts of storm winds, waves, and flooding. Oceanfront property is at risk from natural shoreline migration.
**The storm record demonstrates that the danger is not just to beachfront property, but extends inland, especially on barrier islands. As more and more people live and vacation along the coast, more lives, property and dollars are put at risk. More private development in the coastal zone means more limited access to beaches. The growing congestion, in turn, means that evacuation capabilities may be exceeded. Risks increase with growth. The end result is the spiraling total value of coastal property, and the staggering exposure to potential losses in storms. A survey and projections of USA coastal population change by the National Oceanic and Atmospheric Administration (Culliton et al., 1990) gives a good idea of the magnitude of the growth. In the USA there are 30 coastal states, including the Great Lakes. Counting the District of Columbia, 23 boroughs or census areas in Alaska, and 42 independent cites in Virginia and Maryland that are "county equivalents," there are 451 coastal counties and 1,569 noncoastal counties in the 30 coastal states. In 1960, 80 million people lived within U.S. coastal counties (Culliton et al., 1990). By 1990 the figure had grown to 110 million. By 2010, projections are for over 127 million people to live in U.S. coastal counties (fig1.5). These numbers amounted to a population density of 1,177 persons per shoreline mile in 1988, with 1,358 per mile projected by 2010. This concentration of population and vulnerable development is especially alarming given the projected increase in hurricane frequency and intensity, if such storm conditions are controlled by changing cyclical climatic patterns (Gray, 1992), and possibly to the greenhouse effect. Even without such changes, a reflection on the history of hurricanes and northeasters for the Atlantic and Gulf coasts tells us that nearly 40 million people's lives are going to be affected one way or another in the next few decades. How do we defuse this population bomb?
Hazards, Vulnerability, Risk, and Mitigation
**As long as coasts have existed, waves, tides, hurricanes, northeasters, tsunamis, and all of the associated natural changes have come and gone without notice. These natural processes, which include erosion, flooding, high winds, and similar high-energy events, only became hazards (or hazardous) when humans occupied the coastal zone with fixed habitations and related structures such as docks, wharfs, buildings, pipelines, utilities, and roads. A natural hazard is any process which may cause loss of life or property placed in the path of the process (e.g., at the shoreline, in the flood plain, in the seismic zone). Processes have always been hazardous, but there haven't always been people and development vulnerable to the hazards. Without both hazards and vulnerability, there is no risk. A house on the floodplain is vulnerable, or susceptible to flooding; the risk might be thought of as the potential or probability of damage or loss from the inevitable flood. Another way of looking at risk is to put it in terms of: how much am I willing to lose if I locate in this hazard zone?
Poor development siting and inappropriate island alterations are directly responsible for much of the problem (fig1.6). Single-family houses are often unwisely located in island interior flooding zones, in an inlet hazard area, and directly on the ocean beach. A large area of dunes has been removed for siting of the houses near the top of the figure. Maritime forest has been removed for other houses. Houses located on high ground behind high, wide dunes or within the forested portions of the island interior are at the lowest risk for damage. Building within the forest reduces the amount of protection and also leads to increased degradation and killing of the exposed portions of the maritime forest from salt spray, wind, and wind-borne sand abrasion.
**Risk assessment involves a two-step process, combining information on physical hazards with information about vulnerability (NRC, 1994). The needed information on physical hazards includes types of processes, their intensity, and frequency, plus identification of areas of potential impacts. The vulnerability of a community refers to exposed population, the type and location of structures, critical facilities such as hospitals, shelters, and power plants, evacuation routes, and natural resources (NRC, 1994).
**Defining the natural hazards, measuring the vulnerability, and evaluating the risk are the preliminary steps leading to avoiding the hazards and/or reducing the risks, and in turn the vulnerability. Mitigation is the common term used by planners and managers for reducing the impacts and potential for loss of life and property from hazards. Although mitigation techniques are being applied in the coastal zone, property losses continue to climb.
**Given that the coastal population growth will continue, coastal communities and society at large must take a series of collective actions to stem these catastrophic losses. The following are essential:
o Recognize that the most heavily developed coasts are barrier islands; fragile systems that behave differently from mainland coasts.
o Learn the "Rules of the Sea" as a basis for living with, and managing, barrier islands, and mitigating hazards.
o Develop new whole-island, "natural" mitigation techniques (i.e., island-wide approaches that mimic nature in preserving, augmenting, and restoring environments.
Table 1.1. The costliest hurricanes in U.S. history listed in order of unadjusted cost. Modified (after Hebert and Taylor, 1988).
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