NATURAL DISASTERS AND FRESHWATER RESOURCES Strategic Approaches to Reduce the Impacts of Natural Disasters on Freshwater Resources and its Supply CONTENTS INTRODUCTION A. General B. Background I. IMPACTS OF NATURAL DISASTERS ON WATER MANAGEMENT A. Extreme Hydro-meteorological events 1. Floods 2. Droughts 3. Storm surges B. Effects of Climate Variations and Climate Change 1. El Nin~o 2. Climate Change C. Geological Catastrophes 1. Earthquakes 2. Volcanoes D. Human Induced Disasters 1. Pollution II. RISK MANAGEMENT A. Structural Measures B. Non Structural Measures C. Emergency Response III. CONCLUSIONS AND RECOMMENDATIONS FOR STRATEGIC ACTION A. Conclusions B. Recommendations and Priority for Strategic Action 1. Growing Awareness 2. Integrated Freshwater Resource Management 3. Generation of Financial Resources 4. United Nations Responses in Support of Actions INTRODUCTION A. General 1. The primary goal of natural disaster reduction is to lessen the impact of hazards on human lives. One of the most severe hazards causing natural disasters is that of floods. Yet ironically, droughts are also an important cause of natural disasters. Water management is therefore an important issue in natural disaster reduction. 2. Water is the most valuable resource for societies: an essential component of welfare and productivity. The world■s agriculture, hydroelectric power production, industrial needs, inland navigation are dependent on the natural endowment of surface and groundwater resources. Reducing the impacts of natural disasters on water resources is therefore necessary for sustainable development. 3. All natural disasters have impacts on water resources. Their protection should systematically be taken in account within preventive and mitigation measures. Distinction should be made between water-related disasters and disasters affecting water resources. «Water-related disasters» is a term referring to floods and droughts, i.e. disasters which find their origin in hydro-meteorological extreme events but this term does not specifically include their impacts on water resources, even though both are closely linked. Nevertheless, other disasters such as earthquakes and volcanoes have also dramatic effects on water management and freshwater supply. 4. Progress in the field of integrated water management, could at present, allow us to cope with the complexity and specificity of natural disasters caused by extreme hydrological events. The present document is an attempt to deal comprehensively with the impacts of natural hazards on water resources and freshwater supply, and proposes strategic approaches to reduce them. B. Background 5. This document is a joint International Decade for Natural Disaster Reduction (IDNDR) / World Meteorological Organization (WMO), contribution to the sixth session of the Commission on Sustainable Development (CSD) scheduled to meet in April 1998. It provides an input for the Report of the Secretary General on Strategic Approaches to Freshwater Management. 6. Disaster prevention and mitigation with regard to freshwater is an issue addressed in Agenda 21 (United Nations Conference on Environment and Development ; Rio, 1992) : «Water resource management must be developed within a comprehensive set of policies for (i) human health; (ii) food production, preservation and distribution; (iii) disaster mitigation plans; (iv) environmental protection and conservation of the natural resource base...» 7. Following recommendations from various reports mentioning the need for water-related, or more specifically, freshwater resource-related disaster mitigation and preparedness, IDNDR is honoured to provide this document in line with the Mar del Plata Action Plan (Argentina, 1977), the International Drinking Water Supply and Sanitation Decade (1981-1990), the Technical Conference on the Hydrology of Disasters (WMO, 1988), the Dublin Statement (International Conference on Water and Environment, 1992), and in accord with considerations of the Committee on Natural Resources of the Economic and Social Council (see E/C.7/1994/2). 8. The impacts of natural disasters on water management will be reviewed in the first section. The current methods in water-related risk management will be presented. In order to face new challenges and risks associated with the 21st century development requirements, recommendations for priorities in strategic actions for protecting water resources and freshwater supply will be proposed. I. IMPACTS OF NATURAL DISASTERS ON WATER-MANAGEMENT A. Extreme Hydro-meteorological Events 1. Floods 9. Floods are the most common cause of natural disaster and lead to the greatest number of deaths and the most physical damage. However, even if floods are perceived as causing the most severe water-related disasters, their potential impact on water supply and water-resource management is often not taken adequately into consideration in disaster prevention activities. The reason for this is that priority is generally given to the protection of lives and property. It is also because in times of abundance of water, access to drinkable water is often not questioned. The excess of water during floods is difficult to use because it is often contaminated by mud and other pollutants. This water should be carefully stored in reservoirs and purified, especially since floods can destroy water purification and supply systems. 10. A flood plain is land situated next to a river and directly subject to flooding. Because flood plains are generally flat, located near water and usually fertile, they have been attractive places for human settlements and development since the dawn of civilization despite the risk of loss of property and lives from flooding. Flood plains, through their multiple ecological functions, naturally control flood and erosion by reducing flow velocities, flood peaks and by stabilizing soils. They also maintain the supply and quality of groundwater by promoting infiltration and aquifer recharge and by increasing base flows. Finally, by reducing sediment loads, filtering nutrients and pollutants, processing organic and chemical wastes, and by moderating water temperature, they maintain surface water quality. 11. Therefore, in addition to protecting developments in the flood plains from loss, any flood plain management plan should also aim to protect the natural and cultural resources located in the flood plain. The protection of these resources will not only lead to the maintenance of a good quality water supply but will also preserve the natural flood-alleviating functions of the flood plains. In view of such facts, flood control measures presented in paragraph II, should not only aim to protect lives and property but should also integrate the protection of water resources and supply. Such measures will be proposed in chapter III. 2. Droughts 12. Droughts and floods are at opposite hydrological extremes. While water is regarded as a given, something to be taken for granted, in some countries where water shortages almost never occur, it is something rare and precious, for example in Africa, in small island developing states (SIDS), and in developed countries such as in the USA and Australia. 1997■s World Day for Water (WMO - 22nd March 1997) was being undertaken on the theme "Water Resources Assessment", and with the slogan: "The World■s Water - Is there enough ?". Even though this questions remains an open one, when considering future global aspects of water use in relation to increased urbanization, population density and industrialization, the answer is definitely negative for some parts of the world today. 13. Droughts are a consequence of the combined lack of the runoff to rivers, precipitation and groundwater resources. The consequences of droughts are felt most keenly in arid areas. However, drought should not be confused with aridity nor with desertification which might be caused by land abuse. Droughts occur on all continents (Chile, Mexico, India, and China), though recently the most devastating drought occurred in the Sahel Desert of Africa. Development in these countries is hindered by droughts. 14. Deforestation and overgrazing in many countries of the world lead to desertification. Therefore, desertification in addition to climate change, make the problem of droughts a global one. However, well managed lands will recover from droughts with minimal adverse effects if the rains return. On the other hand, the combined effect of drought and land abuse may lead to faster erosion, faster run-off of river water and larger floods without replenishment of the aquifers if the rain returns. 15. The problems of floods and droughts are two-fold : - they are both hydrological extremes related to weather and climate ; - their impact can be worsened by careless human activity. As will be seen in chapter II, measures to reduce their impacts can be studied jointly since for both, it is necessary to store water, to control its flow and to enhance its infiltration in the soil. Their relation with climate can also be approached simultaneously. 3. Storm-surges 16. Many floods in coastal areas and in river estuaries of a continent or an island are due to storm-surges which result from the sea being driven onto the land by meteorological forces. Storm-surges are commonly associated with tropical cyclones but they can occur with any intense storm. Flooding due to a storm-surge can have destructive effects, even more than the strong winds. Wave action, normal tides and storm-surges can have a combined effect resulting in high-water levels which can be damaging. Buildings, roads and public utility services may be destroyed or disrupted. Powerlines may be downed by the storm and desalination units may be disabled. Water storage tanks may be destroyed and sewage treatment systems disabled. 17. The violence of a storm-surge is most often be followed by water scarcity. Not only may water-supply systems be disrupted for several months, but the intrusion of saltwater would burn grass, kill bushes and affect the freshwater resources. Water quality may be affected after a storm-surge and many fish and shellfish may perish. Aquatic habitats may be disturbed by physical disruption of the shoreline, freshwater flowing into lagoons as a result of the plentiful rains. B. Effects of Climate Variations and Climate Change 18. Floods and droughts, even if local phenomena, can be related to large-scale or global climate mechanisms. Climate variations is a term referring to «year to year» or inter-annual fluctuations in the annual cycle, including also anomalous cycles ranging from two to ten years in duration. Climate variability persistent over a ten years period is referred to as climate change. Through the study of atmospheric teleconnection mechanisms between remote areas of the planet, scientists are now increasingly able to link extreme weather events such as droughts and storms with climate variations and climate change. 1. El Nin~o-Southern Oscillation (ENSO) 19. One of the most spectacular climate variation consequences is El-Nin~o. The El Nin~o event, a warm water current along the coast of Peru and Chile, is part of a climatic phenomenon known as the El-Nin~o-Southern Oscillation (ENSO) which strongly affects tropical and mid-latitude countries. Impacts of ENSO are droughts over southeast Asia, heavy rains in the tropical Pacific and the west coast of the Americas at tropical and mid-latitudes. At the same time droughts appear further east, over northeastern Brazil and southern Africa. The generation of ENSO is not yet fully understood. Its recurrence interval varies from two to seven years, with an average of four years. 2. Climate Change 20. The Working Group II of the Intergovernmental Panel on Climate Change (IPCC, 1995) concluded that: «There is evidence, from climate models and hydrological impact studies, that flood frequencies are likely to increase with global warming». Global warming can be expected to produce changes in the frequency of intense rainfall. Higher sea-surface temperatures can be expected to increase the intensity of tropical cyclones and to expand the area over which they may develop. Rainfall intensity is likely to increase with increasing greenhouse gas concentrations and there may be an increasing concentration of rainfall on fewer rain days. 21. Changes in the magnitudes of snow-melt and rain-on-snow floods will deserve particular attention in some temperate regions ; floods caused by snow-melt may increase. Impacts of climate change are expected to be greater on Tundra Lands and in alpine regions. Deglaciation on temperate mountains would increase sediment loads in alpine rivers and accelerated sedimentation in lakes and artificial reservoirs. Lakes dammed by landslides, moraines and glaciers may drain suddenly and produce floods or debris flows of an order of magnitude larger than normal stream flow. Less snow and glacier ice will influence the seasonality of river flow by reducing melt-water production in the warm season. The expected smoothing of the annual runoff amplitude could be both beneficial (e.g. energy production in winter, reduction of summer flood peaks) and adverse (e.g. reduced water supply for summer irrigation in dry areas, more frequent winter floods). The general tendency in high mountains will be an increased vulnerability of people, transport routes, and economic infrastructures. 22. As climatic warming occurs, there will be notable changes in the hydrology of Arctic areas. River-ice regime might be altered and substantial effects on the hydrology can be expected that will affect flow, water levels, and storage. For cold continental rivers, many hydrologic extremes, such as low flows and floods, are frequently more a function of ice effects than landscape runoff. Projected climates will delay the timing of freeze-up and so prolong the autumn low flow period. At break-up, the rapid hydraulic storage and release of water by river-ice jams often forms the most significant hydrologic event of the year. Of all river-ice processes ice jams are the major source of economic damages. Changes in damages from such events depend on how climate change affects the frequency and severity of river-ice freeze-up and break-up events. 23. Drought has generally received little attention, but it is reasonable to think that an increase in the frequency and intensity of floods may be associated with an increase in the occurrence and severity of droughts in order to compensate the first extreme and to reestablish the natural energy and water balance. 24. It thus appears that progress in climatology and in the development of numerical models not only enable scientists to relate extreme weather events, such as floods and droughts, with climate variations like ENSO, but they can give some insight to climate change scenarios due to global warming, such as sea level rise and changes in frequency, strength and geographical distribution of extreme events. These results should be of great help in taking the right measures and in building up the adapted policies. 25. In view of possible climate change scenarios, natural disaster prevention and mitigation have an even greater importance. It is now possible to build up policies based on climate studies results, in order to get ready for the expected impacts of climate change. Until now, states and societies have learned from the past and may be, more or less, prepared to face certain events which are recurrent. But up-to-date measures and policies will no longer be sufficient if the intensity of extreme events increases and if their geographical distribution changes. The uncertainty brought on by climate change will have to be taken into account in risk management. C. Geological Catastrophes 1. Earthquakes 26. Recently, urban growth in areas with a high risk of seismic activity has highlighted the risk of disruption faced by resources and water supply infrastructures. This risk is particularly important when considering that the increasing population density of certain cities is already reaching the limits of water resources available. The rapid industrial expansion as well as the increase in waste waters also create serious pollution hazards in earthquake prone areas. 27. The impacts of earthquakes on water management and development include dam failure, and the ensuing flooding. This is particularly relevant since large reservoirs may increase the seismicity of certain areas. Water pipelines might also be disrupted. The resulting water cuts will affect the emergency response. The damaged water system will, with time, increase, the number of casualties for a given earthquake. 28. Water leakage due to the fissuring of the pipelines and water reservoirs associated with ground deformation and soil failure may also occur. The resulting rise in groundwater levels under a city may result in subsidence and an increase in the risk of liquefaction during the aftershocks. The risk of pollution due to the collapse of liquid storage tanks and other industrial installments are to be considered as well. 29. In many areas, water for irrigation, domestic and other uses, is transported in large quantities through open aqueducts. Ground shaking may result in negligible local damage or readily repairable failures, but a major earthquake would destroy such aqueducts and restoring them to full capacity may require many months. Water wells may also be affected by earthquakes, when drilled in unconsolidated material. These wells can be severely damaged through strong ground shaking, lateral displacement, and high ground acceleration. 2. Volcanoes 30. An erupting volcano may, of course, destroy nearby water supply structures. Specific to volcanoes are, however, the ash clouds with accompanying pyroclastic flows which may pollute the water resources and cover catchments over a large area, making water unusable for a long time after the eruption. 31. Rivers originating from volcanic zones may have varying chemistries which can affect aquatic ecosystems downstream and subsequently, fisheries. Another natural disaster resulting from volcanic activities is the risk of flooding due to the melting of snow and ice on the flanks of a volcano with ensuing mud flows and landslides. D. Human Induced Disasters 1. Water pollution and contamination 32. Water is necessary for industries which are therefore often located near a river. Thus, natural disasters may not only affect the water resources and their management directly but floods and earthquakes may also destroy industries producing or using toxic materials or dangerous chemicals which might be released into floodwaters. The polluted water may cause death or diseases by poisoning. 33. Such catastrophes, even if induced by natural phenomena, are not « natural » in themselves. Their origin is human industrial activity and they can be avoided through properly applied policies and good decision making. With increased urbanization, increase in population density and industrialization, the problem of pollution might also become more important. 34. Worldwide, considerable disease is linked to the interrelated problems of water quality, water availability, sanitation and hygiene. A reduction in water supply could reduce the water available for drinking and washing, and lower the efficiency of local sewage systems, leading to increased concentration of pathogenic organisms in raw water supplies. Additionally, water scarcity may necessitate the use of poorer quality sources of freshwater, such as rivers, which might be contaminated. Warming of above-ground piped-water supplies also affects water quality through the proliferation of amoebas. 35. Aquatic ecosystems such as ponds and wells, and irrigation and drainage systems, provide breeding grounds for certain parasites or disease vectors. Natural networks of rivers, lakes and marshes, also play a role in the transmission of water-related and vector-borne diseases. If these undergo increased flooding, community water supplies could become contaminated, leading to greater incidence of faecal-oral diseases such as cholera, typhoid, hepatitis A and diarrhea. 36. Developing countries are at most risk with respect to waterborne and water-washed diseases, and urban communities are at greater risk than rural communities. 37. Following a flood, sanitation problems due to disruption of water or sewage systems and prevention of solid-waste collection and disposal, often contribute to increased infectious disease incidence and may kill people particularly through watery diarrhea. 38. Any increase in heavy precipitation and consequently in runoff from agricultural lands, would also be likely to increase contamination of water with chemicals such as pesticides. Human exposure to toxic agents and chemicals from agricultural lands and industrial sites may then occur if water or animals that have become contaminated are consumed. Chemicals may also persist for a longer period of time in flooded soils than in non-flooded soils. II. RISK MANAGEMENT 39. As most disasters are specific to certain locations (flood plains, unstable slopes, seismic regions, in proximity to volcanoes, arid regions), a primary form of prevention consists of avoiding as much as possible these particularly dangerous areas. Such a measure is called « non-structural » in opposition to structural measures, which are protective works (such as dams, dikes, and levees). In the next chapters, both types of measures will be presented with their application to water management from the resource to its supply. A. Structural measures 1. Floods 40. Structural measures to limit the effect of floods include the construction of dikes, flood banks or levees to divert the flood waters ; dams and reservoirs to retain flood waters upstream ; and channel improvements to evacuate flood waters more rapidly. These measures have proved to be very effective in saving lives and property, but they are often expensive, both to build and to maintain. An advantage of structural methods is that they can be effective in protecting existing developments on the flood plain. By contrast, many non structural measures may only benefit new developments. 41. However, structural measures protect losses only up to a certain level of risk. Precaution should be taken that a false sense of total security is not created in people■s mind. If dams and dikes are built to protect the flood plain from a « 100-year » flood (i.e. a flood which intensity appears, in average, once in hundred years) and that a « 500-year » flood occurs, inundation may most certainly not be avoidable. 2. Droughts (a) Surface Water Management 42. Structural measures to limit the consequences of hydrological droughts are similar, in their concept, to those that can be taken for floods. The use of reservoirs for storing the excess flows from wet years is even more important when coping with droughts. But this is not always practical in arid and semi-arid zones where a great deal of stored water is lost through evaporation. Natural drinking ponds are typically very shallow in such regions were 95% of the water is lost by evaporation. One solution lies in increasing the depth of water by creating small deep artificial reservoirs within these natural ponds. A second solution for these same arid and semi-arid areas is to construct small reservoirs in the upper reaches of intermittent streams or to use covered cisterns supplied by natural or artificial impermeable catchments. (b) Groundwater Management 43. The use of surface water supplies is, however, not always possible during severe droughts, so it is necessary to make use of available groundwater resources. Groundwater is less sensitive to evaporative loss and sometimes entirely unaffected, when deep enough. During hydrological droughts, the use of groundwater is general in all countries. Too large a depletion of the aquifer, or its total exhaustion, before the end of drought must be avoided. In countries at all levels of development, aquifer levels are being lowered to dangerous levels by excessive or unsustainable demands, causing land subsidence, saline intrusion and degradation of the fissure network. To avoid overexploitation of groundwater resources requires the quantification of existing water resources and the optimization of their use. Structural measures to optimize groundwater management are the artificial augmentation of aquifer recharge which can take two forms : - increasing the area covered by the floods in arid countries and also increasing the duration of the submersion using a small dam and diversion channel ; - directing water to wells, or to locality of very high infiltration capacity. B. Non-structural measures 44. Non-structural measures include all measures related to policy determination and application such as physical planning (zoning, urban and regional planning, building codes). Other mechanisms, especially in developed countries, would include the use of financial instruments, such as mortgage policies, loans or subsidies for housing or the development of business or insurance as incentives for prevention. Early warning using forecasts are also useful non-structural preventive measures all the more because predictions are progressively more accurate. 1. Floods (a) Flood plain management 45. The non-structural flood defense measures to be considered here include land-use planning and zoning to control the use of flood-prone areas, flood-proofing of existing structures, soil and water conservation to reduce flood flows, and forecasting and warning systems. Among these non-structural measures, the most important one is the control of flood plain development. Flood plain maps indicate the areas with high flood risk and are used as the basis of flood plain management. They show where development needs to be controlled if flood damage is to be reduced. A variety of methods is available for controlling development and the particular methods adopted will depend on the legal and administrative systems of the country. Usually, control will involve some sort form of land-use regulations. 46. The regulations do not need to prohibit all development on the flood plain. A feature of use in most flood plains is that designated activities can be interrupted at flood times with only relative inconvenience. Incentives to choose safer areas, when possible, should be given for developments that would suffer greater from floods (e.g. agriculture, camping or hotels). On the other hand, there are facilities that should never be located in the flood plain because they will be needed in times of flood emergency. These include hospitals, telephone exchanges, electricity sub-stations and emergency control centres and water supply systems. (b) Floodproofing 47. Floodproofing is a means of protecting individual structures from the effects of flooding and consists in elevation above the flood level, and flood walls. These are used to protect houses but can be applied to water plants and purification systems too. Water supply and sewage systems must be safe from flooding and designed to prevent contamination of flood waters. (c) Soil and water conservation 48. The aim of soil and water conservation is to catch more water close to the place where it falls. Such measures are important since human activity often reduce infiltration by increasing runoff and erosion in catchments. Reforestation, terracing, contour ploughing, small ponds or farm dams are beneficial measures to the soil and the water. Promoting a good deep soil profile, capable of storing a substantial volume of water, with a healthy cover of vegetation, whether trees, crops or grass, can only reduce flooding and increase flows during dry periods, thus making the water more readily available for human use. (d) Flood forecasting and warning systems 49. Flood forecasting is based on weather forecasts, telemetry network, radar and satellite data, river gauges network. Input data and model results can be displayed graphically for the use of the forecasters and telexes, faxes or e-mails, for sending forecast results to the end-users can be generated on-line. 50. The general population also needs to know how to respond in case of an emergency and this requires well organized preparedness. The warnings are disseminated to the population by official announcements through the radio and television and through official channels. However, people often fail to heed warnings. 2. Droughts 51. Non-structural measures to reduce the impact of droughts are also very similar to those mentioned for floods. Land-use and management, logistical and social measures for mitigating drought consequences are most practical and effective. In the developed world, an important objective of drought planning is to diversify activities to include drought tolerant ones such as industry and tourism. In the less developed world, the theory of integrated development of drought response fails to take into account the existing cultural, social and economical environment. Inappropriate technology, human and stock disease, inadequate infrastructure, all stand as obstacles to the actual implementation of a sophisticated drought plan. 52. Everything that might obviate the catastrophic consequences of droughts should be attempted. The first set of measures concerns the improvement of the availability of water during the drought by artificial modification of surface flows, by a greater or better utilization of groundwater, or by a combination of the two. The reduction of water losses is also important and consist in reducing the losses in the irrigation system or reticulation network of domestic water supply and reducing evaporation from water surfaces. 53. Unhappily, it has been found impossible to meet water needs during the more severe droughts strictly by technical means. Measures other than the purely technical ones should be taken including : food storage during wet years, insurance, international help. 54. Many of these measures require international efforts, for instance, the integrated management of large basins, or aquifers which straddle national boundaries. Of equal importance is the international effort needed for the selection and marketing of agricultural products. One should also stress the international role of transmitting experience and technology from one country to another, from developed countries to developing countries and also between developing countries facing the similar problems. 55. Finally, there is hope for better prevention and preparedness through the progress of climatological studies dealing with the hydrological cycle. Research would result in a better understanding of the physical mechanisms of the distribution of, and the contents of atmospheric water vapor. Knowledge on freshwater fluxes between the atmosphere and the ocean is also necessary for the study of precipitation and evaporation patterns. Such studies could help to predict floods and droughts better through the understanding of teleconnection between remote areas (i.e. remote cause and effect relations). When coupled with hydro-geological studies, they could also enable enhanced groundwater management practices to be employed. C. Emergency response 56. No system of defense can protect against all hazards nor achieve a zero risk-level. The marginal cost of reducing each additional increment of risk typically rises rapidly as reliability approaches 100%. Hence, decision makers usually deal with 90%, 95%, and 99% levels of reliability as useful performance measures of the available quality and quantity of water. Emergency measures are therefore necessary. 57. Emergency response systems are more or less similar for any natural disaster and involve the same civil defense personnel, first to educate, then to alert the population and, when necessary, to help protect them. In the case of an emergency, response should take in account the possible scarcity of water after a disaster, and advance storage should automatically be part of emergency measures. III. CONCLUSIONS AND RECOMMENDATIONS FOR STRATEGIC ACTIONS A. Conclusions 58. A natural phenomenon, however violent, does not necessarily cause a disaster: there is a disaster only if the phenomenon in question strikes an unprotected or poorly protected human settlement resulting in the loss of lives. Loss of lives may also occur when drinking water is absent or polluted. In general, most countries and societies have faced drinking water shortages due to natural weather and climate variability (floods and droughts), earthquakes and volcanoes, desertification, overexploitation and pollution of the resource base. Therefore, management of water resources inherently entails mitigating the effects of hydrological extremes and providing a greater degree of reliability in the conservation and delivery of water-related services. 59. Water management consists in protecting the water resources and developing its distribution. It should therefore include measures to prevent the loss of water resources and to protect freshwater supply sources and systems from natural disasters and their consequences, in particular, pollution, due to human activity. Some measures to prevent from and reduce the impacts of the main natural disasters have been described in the previous chapters. Even though significant progress has been achieved in disaster and water management, especially in developed countries, natural hazards are suspected to become even more hazardous, due to climate change. Structural and non-structural measures taken in response to past events might no longer be sufficient alone to cope with more intense or geographically altered water-related disasters. 60. Moreover, adequate supply of freshwater may be one of the most challenging problems of the next century : water is not only scarce in arid or semi-arid areas, but is becoming an increasing problem in urbanized regions, because of increase in population density, industrialization and pollution. 61. As adopted at the Nineteenth Special Session of General Assembly (September 1997), Resolution S-19/2 of the -Programme for the Further Implementation of Agenda 21■ recommends that « programmes for sustainable development should give higher priority to the implementation of the commitments made at the World Conference on Natural Disaster Reduction held at Yokohama, Japan from 23 to 27 May 1994. » (see A/CONF.172/9 and add.1). Paragraphs 73 to 75 refer to -natural and technological disasters with an adverse impact on the environment■, and urge for the strengthening of coping mechanisms and policies designed to reduce the socio-economic impact of disasters, in particular an appropriate transfer of technology and adequate early-warning systems. Further recommendations for action are proposed in the next chapter, in order to give higher priority to natural disaster prevention and mitigation, within the framework of freshwater resources management and supply. B. Recommendations and priority for strategic actions 1. Growing Awareness 62. A disaster is not an unavoidable phenomenon - it is an extreme act of nature which, often complicated by human activity, severely impacts human lives. Although not much can be done to prevent natural phenomena such as floods and earthquakes, human activities can modified to become more harmonious with their natural environment, in order to reduce the hazard's impact. This applies to all human activity - from that of individuals, to communities, to nations. 63. Of course, natural disasters cannot be predicted with a great deal of accuracy, and there is always the risk that they could strike anywhere, at any time. Societies prepare for such risks through the acceptance of certain levels of risk and reliability - as explained above, water managers usually deal with 90%, 95% and 99% levels of reliability. These levels of risk and reliability are based on an analysis of cost effective standards, and on a goal of zero loss of lives. However, societies■ prevention and preparation mechanisms are faced with increased risk due to the uncertainty brought on by climate change and because of urbanization, increase in population density and industrialization. 64. A 1% risk, i.e. the risk that a disaster occurs, on average, once in hundred years, may not be a valid concept anymore. Therefore, any false sense of security in the population should be erased through prevention. While some populations may be familiar with water scarcity and recurrent natural disasters such as cyclones or floods and droughts, a very high number of people not only in developing countries but also in developed countries, have no knowledge of emergency response. 65. To ensure that a culture of prevention prevails in the twenty-first century century, IDNDR proposed a Action Plan 1998-1999 which was endorsed by all Members of the Scientific and Technical Committee for IDNDR at its ninth session, held in Geneva from 13 to 17 October 1997 and positively presented the 3rd November 1997 at the fifty second session of the General Assembly under Agenda item 98 (d), (A/52/560). 66. One important aspect of the Action Plan 1998-1999 relates to the anticipation of the kind of disasters likely to prevail in the twenty-first century. Early warning, as well shared knowledge and technology issues are primary themes of the plan upon others based on the original aims of the Decade. Successful early-warning depends on translating technical and scientific knowledge into an understandable message that informs a political decision-making process. Early warning is therefore a cross-cutting issue, and the role of the Decade■s programmes as a bridge between science and the users is vital. (see A/52/561). 2. Integrated Freshwater Resources Management 67. No matter how effective water policies may have been in guiding water resources management over the past decades, such policies may no longer be suitable for meeting the challenges of the next century. 68. At a national level, water resources management is typically divided among a number of governmental sectors and/or ministries. This means that water policies are not the exclusive domain of water as a resource sector but overlap with other sectoral policies. In many countries, the ministry of agriculture has purview over irrigation, and many policies concerning this extremely important water use are established by this agency. Similarly, other water use such as hydroelectric power and navigation are the policy domain of the ministries of energy and transport. Urban and rural water supply and sanitation are often concerns of the ministries of health and human settlements, while environmental agencies establish policies for water quality and preservation of natural aquatic ecosystems, and forestry agencies are often involved in watershed management activities which have major repercussions on water resources. In addition, macro-economic policies on finance, budgets and trade can have important impacts on water resources management. 69. Since a natural disaster affects all sectors, there is a need to develop an overall water policy based on appropriate land-use management. To alleviate human induced droughts and floods, occurring on a regional scale due to inappropriate land-use practices, standards for land-use should be developed to minimize erosion and maximize the interception and infiltration of water. These standards should be developed in cooperation with the aid of the scientific community. 3. Generation of Financial Resources 70. Money may be a leading constraint for the improvement of water management and freshwater resource protection. One way of dealing with the financial problem and to obtain the needed additional funds would be through charges for water pollution or for water consumption. However, most of the people who are currently unserved by water supply in developing countries are poor and unable to pay the full cost of additional services. Since water is crucial for development in any country, public, governmental and international commitment to water management and freshwater supply should be increased as a high priority investment. 71. Increased flood frequencies probably would lead to increased expenditures on flood management. There is a lack of information about the economic impact of droughts and therefore, only marginal interest exists in planning for droughts. The magnitude of drought impacts is assumed to be less than that of other natural hazards because losses associated with other natural hazards are more evident and generally are incurred during short periods of time. In contrast, drought losses generally are distributed over longer time periods. When the true costs of drought are known, drought losses can dwarf the losses from other natural hazards. 72. The World Bank has laid out a framework for water resource management that is expected to serve the needs of developing nations well into the next century and to meet objectives of Agenda 21 of the Rio Conference on Environment and Development. At a regional level, some banks have also become aware of the need for proactive mitigation measures before disasters strike and include vulnerability analysis and risk assessment in their projects. 73. At the global scale, the international insurance and reinsurance industry may be seriously threatened by global warming effects. The primary purpose of insurance is, of course, to pay for the damage caused by a disastrous event, but it is also often recommended as a means of good development. Insurance could be a useful tool for preventive measures if its cost is in proportion with the risks. It could thus encourage people to settle or to move in safer areas. 74. In most developing countries, the full cost of insurance in high-risk areas is too financially burdensome for many property owners. Insurance premiums must be based on a full assessment of risks, for instance, with the use of mapping data. In developing countries, this assessment is usually lacking and the general interest for buying such insurance policies is low. Therefore, it is difficult to control construction of economic structures in high-risk areas of most developing countries except through incentive measures. 75. By encouraging the protection against natural disasters, through loans or assistance for housing or business, the government can also implement prevention measures and, in so doing, create the conditions for a culture of prevention to develop. 4. United Nations Responses in Support of Actions 76. The International Decade for Natural Disaster Reduction (IDNDR), launched its 1997 public awareness campaign around the theme « Water - Too much...Too little...Leading Cause of Natural Disasters ». It aimed to raise the awareness of the fact that unsustainable development patterns that ignore sustainable water management are exposing urban and rural communities to greater risks. 77. IDNDR has established a regional office for Latin America and the Caribbean. This helped to raise regional interest in making prevention and mitigation measures a development priority, in particular in the health sector. An IDNDR proposal for « Disaster mitigation and preparedness for water supply systems in Latin America and the Caribbean » has been elaborated together with the Pan American Health Organization (PAHO), a regional office of the World Health Organization (WHO). The project is funded by Germany and its objective is the prevention and mitigation of damages caused to water supply and sewage systems (treatment plants and pipelines). 78. Since water is essential for sustainable development, prevention and mitigation measures to reduce the socio-economical impacts of natural disasters should include the protection of water resources and of freshwater supply. Conversely, water managers should take into account the prevention and reduction of water-related disasters. This could be achieved through the implementation of similar projects as the one conducted in Latin America and the Caribbean. 79. Newly observed phenomena, such as the possibility of long term climate change with the expectation of disastrous effects on a global scale or, on a shorter term, the irregular occurrence of El Nin~o- Southern Oscillation, create further uncertainties and new challenges for institutionalized warning practices. The combination of the forces of natue with the ill-considered, or uncontrolled, behaviour of humankind, can easily increase the vulnerability of communities and threaten the assets on which they must depend. 80. In that context, the General Assembly urges the Secretary General to include th El Nin~o Southern Oscillation (ENSO, or most commonly known as « El Nin~o ») phenomenom and its consequences in the ongoing activities of IDNDR to improve the effectiveness and increase international coordination of early-warning systems with regard to natural and similar disasters (see A/52/...(A/C.2/52/L.37). 81. In line with the resolution on « International cooperation to reduce the Impact of the El Nin~o phenomenom » adopted by the General Assembly on (date?), at its fifty second session (A/52/... (A/C.2/52/L.37), it is recommended that the Commission on Sustainable Development : (i) Encourages and supports the elaboration and implementation of national, regional and international projects aiming at reducing and preparing the impacts of disasters on water resources and water supply systems. Such projetcs could be part of an existing, or the starting point of new Natural Disaster Reduction and Prevention programme. (ii) Encourages the research activity on climate and its impacts in the context of natural disasters. Moreover, existing scientific knowledge should be applied and technology should be used to better : - control human occupancy of flood-prone lands; - plan drought mitigation measures, in particular adequate land- use management. 82. In this vein, climate information and prediction services, including the frequency and intensity of past storms, data on air humidity, precipitation, evaporation, runoff, river or reservoir gauges, could be used and developed for water management and disaster reduction. WMO has responsibility at the intergovernmental level for coordinating and supporting action by Member States to collect and distribute the meteorological and hydrological data and information that are needed to forecast water-related disasters and mitigate their effects. This involves the World Weather Watch, the Hydrology and Water Resources Programme of the Organization and the Climate Information and Prediction Services (CLIPS) project which aim is to provide the various users (decision makers, policy makers) with a package of relevant climate information and prediction services. Such tools are developed from statistics based on observation, real-time satellite observation and numerical models results. The implementation of integrated information management systems and real-time data observation and reporting systems, could provide the elements to build and organize disaster prevention. 83. The Commission on Sustainable Development is therefore invited to: (i) Support and encourage coordinated efforts among regional, national and international players in the use and development of modern climate information and prediction services. (ii) Support and encourage the transfer of technology and capacity building necessary to the development of such services, particularly in developing countries; (iii) Encourage international exchange of hydrological and meteorological data for conducting studies and support projects aiming to: - develop forecasts of flow and extreme hydrological regime in basins with joint use of water resources; - detect and prevent disasters due to insufficient water or temporary lack of water. 84. In order to reduce the vulnerability faced with extreme hydro-meteorological events, it is also recommended that the Commission on Sustainable Development: (i) Support and encourage Governments to apply such climate services to: - adopt a loss-minimization strategy for flood management, including structural and non-structural measures such as flood- proofing structures, flood insurance, flood warning systems, evacuation and restoration plans. - base redevelopment programmes following flood disasters on risk-minimization land-use controls and management strategies. Public investments, subsidies and incentives on private investment for redevelopment, should be in accord with such programmes. - plan drought mitigation measures based on specific rules for reducing water withdrawals. Efficient and equitable sharing of limited resources, through pooling of available supplies, allocations of use in line with the greatest social value, with appropriate compensation for losers may thus be achieved. - preventing and mitigating damages to water supply and sewage systems. By reducing the vulnerability of water supply systems to natural hazards, the population is less exposed to water borne disease risks. (ii) Encourages Governments to develop policies, regulations and controls to reduce risks of water pollution due to the effects of natural disasters on the production and/or use of dangerous chemicals and toxic materials. 85. Such measures are also relevant to other international programmes, namely: - the United Nations Convention to Combat Desertification which was adopted by 108 parties in June 1994 and entered in force in December 1996; - the United Nations Centre for Human Settlements (« Habitat »). Its outcome, the Habitat Agenda (Habitat II ; Istanbul, June 1996), reflects the priority issues to be addressed, such as natural disasters, availability of freshwater, environmental pollution and climate change. 86. Since many United Nations Agencies are involved in these programmes and in others, also relevant to water management and freshwater supply, it is recommended that the Commission on Sustainable Development: (i) Call on Member States to support the efforts undertaken in those programmes in order to achieve loss reduction as soon as possible, through close collaboration and concerted action at all levels: - at an international level, between United Nations Agencies; - between nations themselves, especially between developed and developing countries, and between countries sharing the same water resources, the same risks, and the same goals, i.e. to reduce vulnerability to natural disasters ; - at a national level, between Ministries concerned with any aspect of water management as well as with natural disaster reduction ; - at an individual level between decision makers, policy makers, scientists and users.
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Date last posted: 8 December 1999 15:15:30