FOREWORD

During the last two decades natural disasters have tended to be more destructive as they affect ever larger concentrations of population. While the response of the International Community has primarily focussed on relief action, it is now also realized that the actual and potential consequences of natural hazards are becoming so serious and so increasingly global in scale, that much greater emphasis will henceforth have to be given to pre-disaster planning and prevention.

The effects of natural phenomena must be viewed not only in humanitarian and broad social terms, but also in economic and development terms since natural disasters are indeed a formidable obstacle to economic and social development. When calculated as a percentage of gross national product, the losses caused by disasters in many disaster-prone developing countries more than off-set economic growth. Consequently, there has been a growing awareness by Governments of the need to pay more attention to disaster preparedness and prevention, and to recognize the fact that pre-disaster planning should be an integral part of national development policy.

In the developing countries, rapid urbanization and the increase of populations living or settling in hazardous areas are matters of growing concern, as they contribute to ever heavier losses of life and to mounting costs of disaster damage. In disaster-prone areas, orderly urban expansion becomes prohibitive unless investments in infrastructure, housing and other services are protected from such damage at all stages of their development.

The formulation and enforcement of land-use policies and plans, as well as appropriate building codes, are key factors for the orderly establishment and safe growth of human settlements. These should logically be based on knowledge of existing natural hazards present and on analysis of the disaster risks which may result. This method of risk identification and evaluation has been referred to in the past by UNDRO as “vulnerability analysis”. Through vulnerability analysis it becomes possible to make rational decisions on how best the effects of potentially disastrous natural events can be mitigated through proper planning, as well as through a system of permanent controls.

The concept of “vulnerability analysis” has over the years been developed by UNDRO, notably in the UNDRO Compendium of current knowledge on disaster prevention and mitigation (Volumes: 3 - Seismological Aspects, 4 - Meteorological Aspects, 5 - Land Use Aspects, 6 - Engineering Aspects (under preparation), 7 - Economic Aspects), and in two technical co-operation projects in pre-disaster planning: Composite Vulnerability Analysis, A methodology and case study of the Metro Manila Area, Report of an UNDRO Technical Advisory Mission, 1977, and Planning for the Prevention of Natural Disasters, Central American Regional Project, Report of a Technical Co-operation Mission 1978.

In 1979, after six years of research and development, UNDRO convened an international Expert Group Meeting of scientists and planners specialized in the major natural hazards of meteorological, geological and geophysical origin, to review UNDRO’s work in vulnerability analysis, provide further guidance on defining concepts and developing methodologies for applying the results of such analysis to practical physical planning and building techniques in disaster-prone developing countries, and lastly to advise UNDRO on its further activities in this field. The present publication is the report of that meeting.

Geneva
August 1980