CHAPTER 4

MITIGATION

Mitigation — actions taken to prevent or reduce the risk to life, property, social and economic activities, and natural resources from natural hazards — is central to the Decade initiative. Awareness, education, preparedness, and prediction and warning systems can reduce the disruptive impacts of a natural disaster on communities. Mitigation measures such as adoption of zoning, land-use practices, and building codes are needed, however, to prevent or reduce actual damage from hazards. Avoiding development in landslide- and flood-prone areas through planning and zoning ordinances, for example, may save money in construction and reduce the loss of life and damage to property and natural resources. Postdisaster studies continue to confirm the fundamental fact that community investment in mitigation pays direct dividends when a disaster occurs.

Development trends in the United States underscore the need to instill a new commitment to mitigation. The National Institute of Standards and Technology (NIST) projects a national investment of $4 trillion during the 1990s in new construction and infrastructure. Advances in the fields of hazard and risk assessments are providing decision-makers with increasingly accurate and useful information on the potential impacts of natural disasters on society. The challenge is to apply this information and translate current understanding of natural hazards into meaningful action at the community level to protect the substantial investments in new and existing development. Equally important is the human side of mitigation; programs should reflect the needs of an urban, aging, technologically oriented society.

Despite increasing vulnerability to natural disasters, many communities resist adopting mitigation programs. The barriers are economic, social, and political, and mitigation is often perceived as restrictive, costly, and incompatible with the community's economic development goals. Mitigation may involve solutions that are technically sound but politically unpopular. In this context, elected officials are often reluctant to pursue mitigation programs vigorously.

Progress toward adoption of mitigation practices will require community commitment, recognition of constraints and barriers, and innovative solutions. Flood-prone areas, for example, could be incorporated into community-enhancing open space, wildlife and recreation attractions, or hiking and physical fitness trails. New awareness and education programs need to be developed to foster incorporation of the lessons learned from disasters and the findings from social research into mitigation practice.

Mitigation initiatives, above all, need to involve the key groups that participate in developing, adopting, implementing, and enforcing mitigation — public officials, finance and insurance specialists, engineers, planners and architects, civic groups, marketing specialists, educators, and researchers. To be effective, mitigation requires a multidisciplinary team approach free from domination by any one special interest group; each discipline has a role and contribution to make. Close communication and coordination among researchers, practitioners, and policymakers increase the likelihood that effective mitigation programs will be implemented.



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A SAFER FUTURE: Reducing the Impacts of Natural Disasters CHAPTER 4 MITIGATION Mitigation — actions taken to prevent or reduce the risk to life, property, social and economic activities, and natural resources from natural hazards — is central to the Decade initiative. Awareness, education, preparedness, and prediction and warning systems can reduce the disruptive impacts of a natural disaster on communities. Mitigation measures such as adoption of zoning, land-use practices, and building codes are needed, however, to prevent or reduce actual damage from hazards. Avoiding development in landslide- and flood-prone areas through planning and zoning ordinances, for example, may save money in construction and reduce the loss of life and damage to property and natural resources. Postdisaster studies continue to confirm the fundamental fact that community investment in mitigation pays direct dividends when a disaster occurs. Development trends in the United States underscore the need to instill a new commitment to mitigation. The National Institute of Standards and Technology (NIST) projects a national investment of $4 trillion during the 1990s in new construction and infrastructure. Advances in the fields of hazard and risk assessments are providing decision-makers with increasingly accurate and useful information on the potential impacts of natural disasters on society. The challenge is to apply this information and translate current understanding of natural hazards into meaningful action at the community level to protect the substantial investments in new and existing development. Equally important is the human side of mitigation; programs should reflect the needs of an urban, aging, technologically oriented society. Despite increasing vulnerability to natural disasters, many communities resist adopting mitigation programs. The barriers are economic, social, and political, and mitigation is often perceived as restrictive, costly, and incompatible with the community's economic development goals. Mitigation may involve solutions that are technically sound but politically unpopular. In this context, elected officials are often reluctant to pursue mitigation programs vigorously. Progress toward adoption of mitigation practices will require community commitment, recognition of constraints and barriers, and innovative solutions. Flood-prone areas, for example, could be incorporated into community-enhancing open space, wildlife and recreation attractions, or hiking and physical fitness trails. New awareness and education programs need to be developed to foster incorporation of the lessons learned from disasters and the findings from social research into mitigation practice. Mitigation initiatives, above all, need to involve the key groups that participate in developing, adopting, implementing, and enforcing mitigation — public officials, finance and insurance specialists, engineers, planners and architects, civic groups, marketing specialists, educators, and researchers. To be effective, mitigation requires a multidisciplinary team approach free from domination by any one special interest group; each discipline has a role and contribution to make. Close communication and coordination among researchers, practitioners, and policymakers increase the likelihood that effective mitigation programs will be implemented.

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A SAFER FUTURE: Reducing the Impacts of Natural Disasters December 1990 floods in Washington state destroyed acres of young Christmas trees. The financial effect of the loss on this atypical agricultural crop may not befelt for a few years.

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A SAFER FUTURE: Reducing the Impacts of Natural Disasters A program for enhancing the nation's hazard mitigation capabilities should capitalize on opportunities for immediate and near-term success and sustain progress into the next century. Numerous cost-effective mitigation programs should be recognized and profiled. Transferable solutions need to be closely examined. At the same time, a balanced Decade program should address the fundamental problems associated with mitigation — the economic, social, and political barriers. The Committee recommends that every community at significant risk adopt and enforce an appropriate mitigation program, including both nearterm goals and a comprehensive long-range plan for reducing the impacts of natural disasters. To achieve this goal, the Committee proposes that local jurisdictions take the following steps: incorporate both structural and nonstructural mitigation measures in new development, examine ways to reduce the vulnerability of existing structures, take steps to reduce the vulnerability of natural resources, and undertake mitigation training with support from state and federal governments. A program for enhancing the nation's hazard mitigation capabilities should include: Protection of schools and hospitals. All new schools and hospitals should be located and constructed to ensure that high-hazard areas are avoided and that special provisions are made to reduce the potential for damage by natural hazards. In addition, existing school and hospital buildings should be surveyed to determine their levels of resistance to relevant hazards. Strenuous efforts should be made to strengthen facilities that would fail in a disaster. In some instances, legislation may be required to ensure that mitigation actions are taken. The Committee believes that special emphasis should be placed on implementing mitigation measures in schools and hospitals because of their critical role in community life and their heightened importance during disasters. One of this nation's greatest resources — children — spends a large portion of time in school buildings. Schools also serve as primary shelters for evacuees during disasters. All too often, however, school buildings are neither constructed nor maintained to withstand the physical effects of natural hazards, and in many states they are exempt from building codes. As a result, they are potential death traps for the students or evacuees within them. Hospitals and other health care facilities minister to the sick and injured and are the locus of the medical technology and expertise that are essential in a disaster. When hospital facilities fail during a disaster, as they have in numerous recent earthquakes and hurricanes, not only are patients and medical personnel killed or trapped within them, but stricken communities are also deprived of needed medical resources, equipment, and supplies. Wherever economically feasible, communities should strengthen other essential facilities such as emergency operations centers, police and fire stations, utilities, and telecommunications and transportation networks, all of which are critical to emer-

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A SAFER FUTURE: Reducing the Impacts of Natural Disasters Response and recovery plans need to be incorporated into communities ' disaster preparedness. Family plans should include specified meeting places in case family members are separated before or during an event, and local schools need to make plans for protecting and accommodating children until they can be reunited with family. gency response and recovery. Museums, convention centers, theaters, and other places of public assembly should also be included in a program to strengthen buildings. Plans are also needed to include the private sector in mitigation activities for both public and private structures. Adoption of nonstructural measures. Businesses and homes should incorporate nonstructural mitigation measures to minimize injuries and property damage from natural disasters. Furniture and equipment, for example, can be easily secured to reduce injuries and damage from earthquakes. Other nonstructural measures are management of vegetation to reduce damage from wildfires and location of structures away from high-hazard areas. Nonstructural mitigation represents a major opportunity for immediate low-cost action to reduce the impacts of natural hazards on the home and the workplace. The private sector can contribute significantly to promoting nonstructural mitigation. Lending institutions are ideally positioned to incorporate mitigation provisions as conditions for loans, and the insurance and reinsurance industries can adjust underwriting rate structures as an incentive for mitigation. Incorporation of mitigation into new development. Local jurisdictions should ensure that new development is located, designed, and constructed to withstand natural hazards. They should use information from hazard and risk assessments, land-use plans, and zoning regulations to limit development of hazard-prone areas. Compatible uses of floodplains and other hazardous areas should be incorporated into local planning and zoning so that losses are reduced. Such areas could have a high value for recreation, fish and wildlife reserves, open space, or other community use. Building codes that set minimum specifications for design and construction can be a powerful tool for mitigating the effects of natural hazards; lives were saved in the Loma Prieta earthquake as a direct result of seismic design and construction practices implemented two or more decades earlier. Fire codes, dam safety standards, and emergency provisions (e.g., ensuring that power is cut off to broken utility lines) have significantly reduced the damage from natural events. Building codes should be a central part of a mitigation strategy for new construction. Barriers to the adoption and enforcement of modern codes should be identified and strategies developed that

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A SAFER FUTURE: Reducing the Impacts of Natural Disasters include incentives and other mechanisms to overcome community and industry resistance. Although land-use planning, zoning ordinances, and building codes and regulations are the responsibility of local and state government, technical and financial assistance will be needed to adopt and implement these mitigation measures. This assistance should be provided through NIST, FEMA, and professional organizations such as the Applied Technology Council, the Building Seismic Safety Council, and the Earthquake Engineering Research Institute. Protection of cultural properties. Protection of libraries, monuments, historic buildings, works of art, and other cultural resources should be incorporated into mitigation planning and action. Losses in the historic district of Charleston, South Carolina, from Hurricane Hugo show the particular vulnerability of cultural properties to natural disasters. There is a need for both information and practical assistance to reduce this kind of loss. Following a disaster, preservation of historic sites can be an emotional and costly aspect of recovery and reconstruction. Mitigation training should include the issue of preservation to promote informed decision-making and community involvement. National and international groups are working under the aegis of the United Nations Educational, Scientific, and Cultural Organization (UNESCO), the International Council of Museums, and other organizations to raise awareness of the threat of natural hazards to cultural properties and to mitigate or prevent damage and losses. Foundations and private groups can contribute to these efforts. Protection of natural resources. Particularly valuable natural resources such as endangered species of wildlife, fish, and plants should be identified in mitigation plans and protection measures included in disaster response plans. Such natural resources are found not only in the wild, but in zoos and parks as well. Mitigation plans might include particular attention to the location and design of facilities so that a fire or windstorm does not act as a conduit for unexpected damage to important natural resources. For example, pipelines and power lines frequently traverse important natural resources areas. In such cases, it is possible to anticipate probable damage to adjacent natural resources caused by rupture of a pipeline or a broken power line. Automatic flow controls, special breakers, and other features are readily available and can dramatically reduce damage. For particularly valuable and endangered populations of wildlife and plants, prudent planning might include relocating a portion of the population so that a natural event does not result in the loss of the entire population. Government leadership of mitigation implementation. Government at all levels should set an example by requiring that new facilities that it funds, regulates, or leases be designed, built, and located in accordance with modern building codes and sound Whether sparked by lightning or by powerlines downed in a storm, the path of forest fires is unpredictable, leaving behind a stark landscape, here including the blackened remains of a chimney and cement foundations of a cabin.

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A SAFER FUTURE: Reducing the Impacts of Natural Disasters land-use practices. On the national level, in January 1990, the President issued an executive order requiring that federal agencies design and construct all new buildings to be earthquake resistant. Similar directives, supported by active enforcement programs, are needed at the state and local levels, and they should encompass all relevant natural hazards. Such standards should be considered for all publicly funded infrastructures and lifelines such as highways and bridges. As resources permit, the requirements should be extended to existing buildings in a phased program that reflects their vulnerability. Mitigation training. Training programs that focus on contemporary challenges associated with implementing mitigation should be developed and offered. A national training program, supported by the federal government and fully integrated with the preparedness training proposed here, should be developed for this purpose. Its curriculum would include land-use planning, zoning, building codes and regulations, tax incentives, and nonstructural mitigation measures. Case studies from throughout the nation and around the world should be included. Mitigation training programs offered by FEMA and USFS should include more participants, disciplines, and subjects. Mitigation training should be highly interactive, reflecting real problems and issues. For example, how can hazard and risk data be used to promote mitigation at the community level? How can hazardprone land be used in ways that are important to communities but less vulnerable to natural disasters? How can a local emergency manager or other official develop a cost-effective mitigation program? How can mitigation policy and practice be moved up on the political agenda? How can local commitment to hazard reduction be developed? How can historic structures be cost-effectively protected to avoid expensive salvage attempts following a disaster? These and other issues need to be addressed in a nationwide training program. Hazard-specific research. Recent disasters have demonstrated the benefits of mitigation efforts while pointing out the need for research to improve mitigation practice. Although all hazards would benefit from such study, research agendas for earthquakes, landslides, and extreme winds are illustrated below. Earthquakes: There is a need to complete a national seismic monitoring network and establish a cooperative international program in strong-motion measurement and data analysis. Local networks should be established, as needed, to determine the effects of local site conditions on ground motion and the relationship between specific ground motion parameters and the degree of structural damage. The behavior of structures founded on different soil types is another area of research opportunity. The damage distribution in the Marina District during the Loma Prieta earthquake dramatized the effects of soil properties on structures and underscores the need for additional research in this area. Research is needed to develop cost-effective methods for strengthening existing buildings and structures, especially unreinforced masonry and brittle reinforced-concrete buildings. Federal and state governments should encourage the development and implementation of active and passive control systems and other new techniques to improve the seismic resistance of both existing and new buildings. Additional research should be conducted to improve techniques for controlling damage to nonstructural elements such as ceilings, windows, the electrical supply, and domestic gas pipes. Research to improve the design and construction of lifeline systems should be accelerated. Landslides: Each year, landslides in the United States cause approximately $2 billion in damage. Better understanding of the conditions that generate landslides would significantly improve hazard and risk assessments by local jurisdictions. Research is needed to develop designs that mitigate ground deformation and damage to structures, provide a technical base for mitigation measures such as landslide zoning, and test and evaluate innovative landslide stabilization techniques. The application of new techniques in satellite remote sensing, geophysics, and geotechnical engineering for delineating landslide hazard areas should be accelerated. Research is needed to identify the economic, political, and social processes that encourage or impede landslide mitigation programs. This information could be valuable when landslides are considered in insurance programs and local planning and zoning, including the location of key facilities. Extreme winds: Knowledge about wind-force effects on buildings is critical to developing wind speed provisions in building codes and designing wind-resistant structures. Research in this area is lacking; measurements of wind speeds at the height of mid- to high-rise buildings are rarely available.

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A SAFER FUTURE: Reducing the Impacts of Natural Disasters The stucco facade of this building shattered like an eggshell as lava flowing around the base of the three-story structure applied such pressure that the walls shifted and collapsed. A national wind hazard reduction program, modeled on the National Earthquake Hazard Reduction Program, is needed to improve building performance in high winds and severe weather. The program should emphasize mitigation. Schools and medical facilities, in particular, should be subject to stringent building codes. Home and business owners should be provided with “do-it-yourself” instructions on how to strengthen individual structures to withstand winds. High winds can cause substantial property damage and economic loss. Research needs to focus on whether current mitigation practice, including the wind-resistance provisions of building codes, is responsive to the potential magnitude of the problem. Overcoming resistance to mitigation. Barriers to the adoption of mitigation measures need to be clearly identified and innovative strategies developed to overcome resistance. Success stories, computer models, and simulations should be components of such a program. Real experiences can provide both insight into the factors that contribute to successful mitigation programs and the means for communities to capitalize on opportunities that follow a disaster. Computer simulations and other tools that incorporate the tax base, revenues, loss estimates, and other key variables can provide government and industry with information critical to their decision-making. Simulations of past recovery and reconstruction efforts, including decisions and trade-offs, may contribute to appreciation of the value of mitigation.

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A SAFER FUTURE: Reducing the Impacts of Natural Disasters Response and recovery need to be a coordinated effort of local, state, and federal government, private voluntary organizations, and community volunteers. During and after Hurricane Hugo, U.S. Marine Corps volunteers worked with the Salvation Army to move bottled water and other requisite supplies through relief centers and to appropriate locations in a timely manner.