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4 An International Perspective on Avalanche Management Avalanche hazards are a global management concern, affecting Austria, Bulgaria, Canada, Chile, China, Czechoslovakia, France, Greenland, Iceland, India, Italy, Japan, Nepal, New Zealand, Norway, Pakistan, Peru, Poland, Romania, Scotland, Sweden, Switzer- land, the United States, West Germany, and the U.S.S.~. Each nation manages its avalanche hazard in relation to its form of government, appropriate historical precedents, political in- fluences, social concerns, the economic climate, and its technological sophistication. These variables affect the emphasis placed on avalanche management, the implementation strate- gies adopted, and the relative success or failure of the strategies in achieving individual program objectives. When devising strategies to reduce avalanche impacts, the parameters of crow dynamics are targeted as well as the distribution and activities of people. The physical aspects of avalanche control are discussed in Chapter 5; the human element is of concern in this chapter. Of particular interest are the strategies that have been implemented frequently or that have shown greater sophistication in the past decade: these include avalanche legislation and regulation, avalanche zoning, and hazard mapping insurance or disaster relief (Kockelman, 1986~. These strategies are examined in this chapter in an international context, with the following countries selected for comparison: Austria, Canada, France, New Zealand, Norway, Switzerland, the United States, and the U.S.S.R. This sample reflects both the dominant avalanche management interests and a diverse geographic distribution. LEGISLATION Switzerland has both significant avalanche hazard and a well-documented legislative mandate (Frutiger, 1980~. The Swiss Federal Confederation oversees 26 cantons, 12 of which are mountainous. The confederation does not have the power to legislate avalanche safety, but it does have the authority to direct the cantons and communes to legislate. Cantons are responsible for enacting planning or zoning and building laws, and communes are responsible for the safer of life and property and, as such, can impose land-use controls directly. 27

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28 In 1951 the confederation passed an act requiring cantons and communes to adopt avalanche hazard zoning plans. The response was poor; so in 1972 the confederation again passed an act ordering cantons to zone avalanche hazards, threatening severe consequences for lack of action. Most cantons responded: six have zoning codes expressiv for avalanches, five have zoning cocles for hazards in general, ant! one still has no zoning (Frutiger, 1980~. Swiss avalanche zoning is carried out with the aid of subdivision regulations and/or regu- lations and codes that require the subdivicler to submit maps showing avalanche hazards. Maps are subsequently reviewed by local governments and adjusted if necessary. Build- ing regulations and codes specify the conditions that must be met for development to be permitted in or near an avalanche path, including structural design, construction materials, and even avalanche defenses. Thus, both subdivision and building regulations outline the conditions under which a structure can be built. Construction can begin only after zoning maps indicate that building at a particular location will not jeopardize lives and property. In addition, numerous legal precedents serve to define the law if regulations are absent. Of particular significance are decisions concerning safe access and the duty to warn involving the sale of property (Frutiger, 1980~. In the latter case, property sales can be contested if avalanche hazard becomes evident later; a seller can be charged with intentional fraud if he or she does not inform a prospective buyer of a known hazard. The French Alps have avalanche situations similar to those in SwitzerIanci, but land speculation in the 1950s compounded the problems (de Crecy, 19S0~. Regulation is central- ized, with the central government having the obligation to define avalanche hazard! zones. In 1980 the French government created an interministry committee to study mountain safety, which subsequently recommended that the task of mapping avalanches be assigned to the Institute Geographique Nationale (Cazabat, 1972~. Once compiled, avalanche maps became the property of the Minister of Agriculture. Under the French Code de I'Urbanisme (town planning code), areas with avalanche hazards are delimited by a 1974 prefect decree, and within these zones construction can be restricted. The hazard zones must be defined before ~ . , . ~ ~ ~ ~ ~ ~ a building permit can be issued, and the government controls development in these zones through a ou~ct~ng code that requires certain structural specifications. Code limitations can include restrictions on the density of buildings and mandatory evacuation or seasonal use of buildings during periods of high avalanche hazard idle Crecy, 1980~. As of 1979, , ~ ~ . .. . . . ~ ~ , ~ approximately 50 mountain communities in France had avalanche zoning plans representing approximately one-half of the communities with avalanche-prone terrain. The main innovation since 1980 has been the Plan d'Exposition aux Risques (PER), a risk map with legal connotations defined in a 1982 law bearing on natural hazard insurance (Brugnot, 1987~. Although 1982 was a year of decentralization laws in France, the govern- ment decided that responsibility for natural hazards would not be transferred to individual communities, as was responsibility for most other urban planning problems. A subsequent 1984 decree specified the procedures for producing a PER. The PER is developed under the authority of the prefect (as government representative), but approbation of the communities is required. If agreement is lacking between local councils and the prefect, final decisions regarding PER are rendered by a national conciliation court. MuniciDal boards regulate development in Norwav. The national huildin~ code deter- . . . . . . 1 0 - r ~ a ~ - ~-- ~-~~~~-~-~~ - ~~~~~~~o ~~ ~~ - ~ mines whether residential land use will be permitted, stating that the "ground can only be built on if there is sufficient safety against subsidence, inundation, landslides, etc." (Hestnes and Lied, 1980~. If there is inadequate avalanche protection, areas must be classified in area

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29 development plans as dangerous (Ramsli, 1974). Zoning per se is not a mandatory require- ment of municipal governments. The alternative approach of avalanche mapping became the responsibility of the Norwegian Geotechnical Institute in 1972; previously, mapping was carried out by the University of Oslo's Department of Geography (Ramsli, 1974~. Avalanche legislation and regulation in Canada are a provincial and a local concern. In British Columbia the ministry of the attorney general, the ministry of highways and transportation, and the ministry of municipal affairs play key roles in legislating and reg- ulating avalanche hazards. The ministry of the attorney general is involved in avalanche management through the administration of the Land Title Act, RSBC 1979, especially with regard to subdivision plans. If the land in question is in a municipality, subdivision approval is a municipal concern; if, however, the land is rural, subdivision approval is obtained through the ministry of highways and transportation. For rural land, subdivision plans must be accompanied by topographic details that include environmental impact assessments. Within the Land Title Act, subdivision plans can be refused if "the land is subject, or could reasonably be expected to be subject, to flooding, erosion, land slip or avalanche" (B.C. Government, RSBC 1979, C.219, Sec. 86~. Specific reference is made to avalanches; thus, both municipalities and highways have the mandate to control development and refuse it where potential avalanche hazards exist. The ministry of municipal affairs is also involved in avalanche management: under the Municipal Act, RSBC 1979, municipal councils have the power to relocate and close municipal highways, develop community plans, regulate sitings of buildings, and regulate land use through zoning. Municipal councils also have the power to restrict specific uses within a particular zone, and it is this potential management strategy that is particularly useful in preventing large-scale loss of life and property damage from avalanche hazards. Yet as of 1984, zoning had been ad hoc and infrequent (McFarlane, l984~. In the United States the onus to zone lies mainly with state and local governments, rather than federal agencies (Niemczyk 1984~. Most progress has been made in Colorado, where in response to an increase in land speculation and recreational development in the Rocky Mountains (Ives and Krebs, 1978), House Bill 1041 was legislated in 1974. This bill was concerned with hazard zoning for land-use planning; its adoption by local governments was voluntary (Rold, 1979), but counties were required at minimum to map their geological hazards and to use the mapping as a basis for land development approvals. Before devel- opment controls could be implemented, it was first necessary to identify buildings already situated in avalanche paths; in Vail, for example, 40 such structures were identified (Ives and Krebs, 1978~. After the initial identification procedure, a few developers responded by introducing design changes into partly built structures located in avalanche paths; others did not. However, since 1974, new proposals for development have been subjected to strict building codes and regulations. Alta, Utah, also has an avalanche zoning plan. It is administered by the Salt Lake County Planning Commission, which controls development in avalanche zones through building permits (Tesche, 1977~. Another example is Ketchum, Idaho, where about 35 residential lots with buildings were found to have avalanche paths directly affecting them. Restrictions were placed on subsequent buildings through special design specifications; defense structure requirements; confining residence to the period April 15 to November 15; property subdivision prohibitions; and, in addition, a requirement to notify tenants, lessees, read estate agents, and sellers of any avalanche hazards (Mears, 1980~. Similarly, in Placer and Nevada counties in the Sierra Nevada of California, building ordinances enacted in 1982

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30 for avalanche zones place engineering requirements on new construction, reconstruction, and expansion of existing structures and require written notification to renters and buyers (Penniman, 1989a). There are no land-use restrictions for buildings in avalanche paths in Alaska (Tesche, 1977; Hackett and Santeford, 1980; Mears, 1980), although omnibus legislation (Senate Bill 301) passed in May 1980 relates to avalanche warning and control systems (James, 1981~. Through Bill 301, Alaska's Department of Public Safety is mandated to forecast and control avalanche hazards and coordinate an avalanche information program and "to assist local governments and state agencies in identifying hazardous avalanche zones and in developing snow avalanche zoning regulations" (James, 1981~. Thus, a vehicle has been established for future avalanche zoning policies in Alaska. Unfortunately, it is little used. HAZARD DELINEATION Avalanche legislation usually prepares the way for avalanche zoning, which in turn subdivides the land so as to enforce building restrictions. Criteria vary from country to country. Three types of hazard maps are distinguished in Norway: hazard registration maps, geomorphic hazard maps, and hazard zoning maps (llestnes and Lied, 1Ys()~. Hazard reg- istration maps detail historically known avalanches from literature, documents, interviews, and field work. Geomorphic hazard maps add the results of geomorphic investigations, while hazard zoning maps show both actual and potential paths, together with mathematically or ~ ~ ~ ~ . _ ~ . . ~~ ~ ~ . ~ . ~ ~ ~ r . ~ 1 statistically derived runout distances. typical survey maps give general information about hazards at a scale of 1:50,000. Detailed maps at 1:5,000 scale have high accuracy but demand comprehensive and time-consuming field work. Hazard zoning maps include an estimate of potential risk (i.e., future natural hazard activity and damage). Acceptable levels of risk for housing are evaluated in comparison with other types of social risk. The proposed highest tolerable risk level for damage to dwelling houses in Norway is 3 x 10~3 per year (Hestnes and Lied, 1980), well above the proposed international standard for "planned activities" of X ]0 6 (Starr, 1969~. Mapping for communities, highways, construction sites, and power lines is carried out by the Norwegian Geotechnical Institute (H. Norem, Norwegian Geotechnical Institute, Osio, written communication, 1986~. Over 1,000 paths had been recorded in detail by 1980, but the objective is to cover 100,000 km2, nearly a third of the nation's land surface. Some recent mapping has been done based on topographic information alone, using computer- based digital terrain models to identify avalanche starting zones and to establish runout boundaries with empirically based modeling laws (Toppe, 1987~. In the U.S.S.R. a national inventory has been completed. In this inventory, snow avalanche hazards have been placed into the second most significant group of hazards, classed as destructive natural phenomena that seldom cause loss of life but that result in significant damage to the economy, especially industry (Gerasimov and Zvonkova, 1974~. Because avalanches occur in approximately 20 percent of the land area of the U.S.S.R. (Tushinsky et al., 1966; Akifyeva et al., 1978), zoning is important. Russian criteria for zoning are based on vegetation characteristics. It is recommended that no construction be allowed in avalanche "natural-territory complexes of meadow and subalpine elfin for- mations," whereas construction of summer buildings should be permitted in avalanche "natural-territory complexes with mixed forests and pine forests of various ages in which

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31 recurrence intervals range from fifty to three hundred years" (Akifjeva et al., 1978~. This type of zoning explicitly takes into account the frequency of an avalanche, its size, areal extent, impact pressures, and seasonality. Avalanche hazard mapping at a scale of I:SO,OOO was initiated in France in 1964 under the direction of the minister of water and forests (Cazabat, 19729. The scale of mapping was changed to 1:20,000 in 1970, and Cartes de Localisation Probable des Avalanches (CEPA) maps were produced for an area of 7,000 km2 in the Alps and Pyrenees, using photointerpretation, field investigations, and assemblages of local witnesses confronting one another- thus testing the accuracy of recollections against each other or against historical documentation (de Crecy, 1980; Brugnot, 1987~. These COPY maps, prepared in a novel fashion, were distributed to civic authorities responsible for public safety and land-use planning. In addition, French law obliges the government to define the limits of zones subject to natural risk before a building permit can be obtained. Consequently, in 1974, Plans des Zones Exposees aux Avalanches (PZEA) maps at a scale of 1:2,000 or 1:5,000 were introduced as a legal document to cover areas where town planning is envisioned or is in progress (de Crecy, 1980~. Three zones are delimited by specialists in PZEA zone maps. The red zone indicates a high degree of danger and no construction is permitted. The blue zone is an intermediate hazard area that includes extremely rare and yet severe avalanches with return periods greater than 300 years, as well as less severe avalanches with return periods every 30 to 50 years. Construction in the blue zone is permitted only under conditions established by specialists, which include evacuation when required, reinforcement specifications for buildings, protective structures (forests or man-made defenses), and/or annual inspections. A building in the blue zone may be denied windows on walls facing uphill, and the pitch of the roof may be specified (de Crecy, 1980~. Research on mathematical avalanche models was undertaken to provide tools to assist in the delineation of blue zone boundaries and to provide criteria for structural design. The third zone, white, is an area that is most likely safe from avalanches and where construction thus is not restricted. The PER risk map, a legal document defined by 1982 and 1984 laws, follows some of the guidelines of the existing PZEA procedure (Brugnot, 1987~. Red, blue, and white zones are again established; these have implications concerning insurance, as discussed below in the section on Insurance and Disaster Relief. Zoning decisions are nevertheless complicated, involving local governments and appro- bation of the communities involved. Although a general technical handbook describing the state of the art in natural hazard protection was prepared for distribution to local author- ities (Delegation aux Risques Majours, 19SS), additional technical expertise is recognized as necessary. A population of experts is likely to cause discrepancies and inconsistencies; this is considered a problem, since the PER maps are government endorsed and the aim is to treat all citizens in an identical fashion with regard to building restrictions that reflect natural hazards (Brugnot, 1987~. In early discussions concerning the PER procedure, some government officials expected such problems to disappear through advances in technology. This opinion seems unrealistic, despite the recognized need for continued research and de- velopment of scientific tools, such as dynamic modeling, an avalanche data base, and expert systems (artificial] intelligence). Work on the latter topic commenced in 1985 (Brugnot, 1987; LaFeuille et al., 1987~. Switzerland uses two types of hazard maps: avalanche zone plans and avalanche hazard maps. Avalanche zone plans are legitimized by avalanche zoning laws and are legally

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32 bincling; moreover, they are a component of the builcling cocle (Frutiger, 1980~. Avalanche hazarc! maps, on the other hancI, are not legally binding and are merely tools to assist the decision maker in regulating lane} use. The ctistinction between the two types of maps, macle in 1975 by the Federal Bureau of Forestry (Frutiger, 1980), is used in the follomng - c .lscusslon. Under the Swiss color zoning scheme, impact pressure and avalanche frequency are used to quantity the clegree of risk. This is not a purely scientific question but also a political anc! psychological one; authorities have to clecicle the level of risk that shouIc! be accepted (Buser et al., 1985~. The maps are compilecI at scales of 1:25,000 ant} I:10,~0 (~enho~z, 1978; Frutiger, 1970,1972; Buser et al., 1985; cf. Mears, 1979, 1980~. Rec! zones constitute the areas of highest risk. Avalanches are either powerful (impact pressures greater than 30 kN/m2, or approximately 0.5 psi) with a return period of 300 years or less or frequent (return periods up to 30 years), irrespective of intensity (Buser et al., 19SS; Bunclesant fur Forstwesen, 1984~. New builclings and winter parking lots are generally not allowed in this zone. Blue zones have dynamic pressures less than 30 kN/m2 with return periods of 30 to 300 years. Residential development is permitted if it is protected by avalanche defenses or if construction meets design specifications to resist avalanche forces. The specifications can include such criteria as building strength, materials, shape, size, spacing, or function (Kienho~z, 1978~. Churches, schools, hospitals, lodges, and other public places are not permitted in blue zones. The white zone is beyond the limit of design avalanches, though not necessarily outside the range of all possible avalanches. An optional yellow zone has been used to define an area where avalanches are rare or where air blasts occur. Buildings in this zone must conform to building code standards. This area can be impacted by powder avalanches with dynamic pressures of 3 kN/m2 (approx- imately 0.05 psi) or less and a return period greater than 30 years and/or by rare flowing avalanches with return periods exceeding 300 years. The latter are not well understood, and the criteria for determining their occurrence are subject to question (Frutiger, 1980; Brugnot, 1987~. No building restrictions related to avalanche hazard are prescribed. Swiss research continues on natural avalanche dynamics and on avalanche modeling, in order to provide better tools to meet the requirements of hazard zoning (Gubler, 1987, 1989~. In Canada the avalanche hazard line is considered the boundary of large infrequent avalanches, and development is defined as being inside or outside this line. The line, which corresponds to the boundary of the blue and white zones of the Swiss system, indicates how far extreme avalanches can reasonably be expected to travel. Its establishment does not account for return intervals and impact pressures. Occasionally, within active sites, additional categories are used to include frequent flowing avalanches with return intervals of less than 30 years, infrequent flowing avalanches with return intervals exceeding 30 years, and infrequent powder snow avalanches and wind blasts. In addition, a safety distance of 5~150 m (150-450 ft) is added onto the known boundary of the runout zone (Freer and Schaerer, 1980~. These hazard lines are recommendations only, and their implementation is at the discretion of the approval officer. If the developer does not agree with the zoning, an appeal may be made to the approval officer or the courts. Runout distances are established by terrain and vegetation analysis and by mathematical modeling. Base maps in Canada are at 1:50,000, a scale inappropriate for detailed avalanche studies. Aerial photographs are used extensively. No uniform policy exists in the United States. In Colorado, House Bill 1041 (1974) requires local communities to compile hazard maps. Since some of the work subsequent to

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33 this legislation was delegated to the Colorado Geological Survey while other work was given to private consultants (Rold, 1979; Ives and Plam, 1980; Mears, 1980), there are a number of different types of hazard maps and zoning plans, all with different criteria. Avalanche hazard maps compiled by the Colorado Geological Survey are at a scale of 1:24,000 and are published at a scale of 1:50,000 (Mears, 1979~; they define high hazard, moderate hazard, and no hazard areas based on impact pressures and avalanche return periods. "No hazard" is assigned to areas considered! free of avalanches or with return periods up to one or two centuries, or where air blasts might occur, and is ignored for planning purposes. Recommendations are made that no permanent residences be allowed in high hazard areas and that engineering design precautions be adhered to in moderate hazard areas (Mears, 1979~. The Institute for Arctic and Alpine Research has also been involved in avalanche haz- ard mapping in the United States (Ives and Bovis, 1978; Ives and Krebs, 1978; Ives and Plam, 19SO). In the institute's unpublished 1:24,000 maps, avalanche paths are designated according to whether they are active or potential. While these maps give some idea of the location of hazard, they do not have the technical standards required for assisting in regu- lation of specific development in mountain areas. Detailed mapping with impact pressures and return probabilities is desirable for land-use planning in mountain environments. In Alaska, maps indicating high hazard, potential hazard, ant} no hazard have been compiled at scales of 1:250,000 and 1:53,000 (Hackett and Santeford, 1980~. These scales are inadequate for detailed planning but represent a step in the right direction. Detailed maps are available for some areas. With respect to avalanche zone plans, similarities are shared by Vail, Colorado, and Ketchum, Idaho. Both communities have a color scheme to differentiate degrees of avalanche hazard, white being nonhazardous. Red zones correspond to high hazard] ar- eas in which "impact pressures on a flat surface normal to the flow" exceed 600 Ib/ft2 anchor avalanche return periods of less than 25 years (Mears, 1980~. Residential construction is not permitted in rect zones. In blue zones, impact pressures are less than 600 Ib/ft2 and avalanche return periods are approximately 25 to 100 years. Builcling in this zone is permit- ted if design by a registered engineer provides for avalanche forces. This modification to the Swiss definitions recognizes the uncertainty in specifying long return periods in a region of short observational records. Responsibility for providing safe design lies with the property owner or the owner's consultant, not with the community. Another plan, developed for Ophir, Colorado, uses slightly different frequencies and impact criteria. The important factor in all these cases is the incorporation of avalanche zone plans into the city's land-use ordinances. Zone plans for Placer and Nevada counties, California, illustrate some zoning problems for two geographically similar areas faced with identical avalanche hazards. The zone plans are based on a single hazard study conducted for both counties at the same time, by the same consultant, using identical procedures (Penniman, 1989a). Hazards were defined by a red zone (high hazard, occurrence probability for a damaging avalanche 1:209; a blue zone (moderate hazard, probability 1:20 to 1:100~; a yellow zone flow hazard, probability less than I:100~; and a white zone (no hazard). The Placer County ordinance places engineering requirements on new construction in red and blue zones and notification of hazard to property users in yellow zones. In contrast, Nevada County requires engineering measures in red zones and only written notification in blue zones and treats equally the yellow and white (no hazard) zones. The wisdom of ignoring yellow zones can perhaps be challenged

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34 on legal and ethical grounds, and subtle issues arise when property owners appeal hazard ratings based on a site-specific study. As in all cases involving municipalities with avalanche problems, policymakers are in the unenviable position of deciding whether the public good is best served by warning the public of a potential danger or by trying to maintain property values until the danger is proven. INSURANCE AND DISASTER RELIEF Avalanche insurance is not available in many countries; disaster relief is often the alternative. A few exceptions are worth noting. Norway is one of the few countries in which private insurance against avalanche damage can be obtained. However, private insurance is generally not necessary because avalanche damage insurance is compensated by the Norwegian National Fund for Natural Disaster Assistance (Ramsli, 1974; Hestnes and Lied, 1980~. This organization has been active in preventing development in high-risk areas, and has supported pilot hazard mapping projects by the Norwegian Geotechnical Institute. From 1962 to 1971, Norway was subjected to an estimated $~.6 million worth of private property damage from avalanches (Ramsli, 19744. Although insurance was not available earlier in Switzerland (Peria and Martinelli, 1976), in recent years it has become an increasingly popular option. Proposals are now being tendered for using insurance companies to enforce building regulations, and it has been suggested that buildings constructed in hazardous places be denied avalanche insurance (Frutiger, 1980~. Such a strategy might force cantons and communes to implement land-use zoning and thus ensure development only in avalanche-safe areas. In some cases insurance companies are a cantonal institution, and their guidelines carry official legal authority. The most elaborate and well-defined natural hazard insurance system is in France; it is regulated by the PER risk map concept (Brugnot, 1987~. Accordingly, for future or existing construction in red zones, insurance companies may refuse protection; in the former case the possibility also exists for legal prosecution against the community. For new construction in a blue zone, no insurance company can refuse to insure the property if the provisions of the PER have been followed regarding reinforcement or protective structures. For preexisting buildings in a blue zone, the insurance company cannot refuse protection, but the owner has a 5-year period in which to comply with PER requirements. Several aspects of the French system are particularly important: first, natural hazard insurance is implicit, which signifies that no additional insurance cost applies to blue zone properties. Thus, every French household contributes to natural hazard indemnification. The national increase in insurance fees due to natural hazards was about ~ percent in 1985 (Brugnot, 1987~. Second, any refund of damages is conditioned by acknowledgment of the existence of a natural disaster situation by a government panel. To date, practically every avalanche damage case presented for indemnification has been accepted, even disputed ones. Because the most costly part of the insurance scheme, by far, concerns flooding, other hazards have been considered leniently. Most avalanche cases admitted as disaster situations were defined in terms of large snowfalls, but exceptional snow metamorphism also was cited as a criterion to satisfy the specification of a disaster situation. Avalanche insurance in New Zealand can be obtained through a national natural hazard insurance policy (Olshansly and Rogers, 1987~. Any building covered by fire insurance is automatically charged an additional $0.05 per $100 of coverage; the funds are split- 90 percent for the Earthquake and War Damage Fund and 10 percent for the Extraordinary

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35 Disaster Fund, both administered by the Earthquake and War Damage Commission. To qualify for natural hazard insurance, a property owner must have safeguarded the property against a "normal" or "reasonably expected" event. Thus, unless building codes have been met, coverage may be refused or may be assigned a more costly premium. This insurance, however, is only for the "abnormal" event; the "normal" event must be covered through private insurance even though private insurers currently do not like to insure high-risk properties (O'Riordan, 1974~. In the U.S.S.R., insurance against avalanche damages can be obtained from the "Gosstrakh" (Gerasimov and Zvonkova, 1974~. This government-administered insurance agency has a mandate to cover losses from natural hazards. The Soviet government com- pensates owners for all damages to buildings and animals caused by "natural processes not peculiar to a given region" (i.e., abnormal occurrences similar to New Zealand's restric- . ~ err , ~ . ~ ~ . ~ ~ ~ r ~ r tlons). thus, areas that can be insured against avalanche damage are, tor example, forest areas below avalanche runout zones never before impacted by avalanches. In Canada the costs of disaster relief are shared by the federal government and the provinces, since private avalanche insurance is not available. The national agency that ad- ministers disaster relief is Emergency Planning Canada (EPC); its involvement in avalanche disaster has so far been limited to large-scale events. In the absence of relief funding from EPC, other federal and provincial administrations such as the British Columbia Provincial Emergency Program have absorbed the costs. Private insurance against avalanches is generally not available for property owners in the United States. Nevertheless, under lenient interpretation, repairs due to an airborne dry snow avalanche in March 1962 in Juneau, Alaska, were covered by homeowners' insurance policies; the insurance company adjustors determined that the damages were caused by the wind (Hart, 1972~. A national landslide insurance fund has been proposed but not enacted, accompanied by a program for mapping hazard zones and determining actuarial rates (Olshansky and Rogers, 1987~. National hazard relief funds are administered by the Federal Emergency Management Agency (FEMA), and funding of emergencies is shared by the federal government and the states in question. However, no avalanche damage has yet been covered by FEMA funds. FEMA has struggled with the dilemma of how to spend disaster funds not only to aid victims but also to encourage mitigation efforts. With respect to landslides, FEMA has wavered between a liberal policy of paying for stabilization and reconstruction of public infrastructures, which does little to discourage development in hazardous areas, and a strict policy of allowing only emergency repairs (Olshansly and Rogers, 1987~. Finally, personal insurance for skiers (covering, for example, search and rescue costs and legal fees related to injuries to other skiers) is available worldwide from Carte Neige, through La Federation Fran~aise de Ski (WelIs, 1987~. COMMENTS I. Legislation regulating land use in avalanche hazard areas is most restrictive in Switzerland, France, and a few regions of the United States (particularly Colorado). There is a lack of overall legislation requiring local communities to zone for avalanche hazards in Canada, Norway, and most locations in the United States, although in Norway the National Fund for Natural Disaster Assistance has been active in preventing development in areas at

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36 risk. Legislation is desirable that requires properties with known avalanche hazards to be registered, since such legislation offers protection to a buyer. 2. Avalanche hazard maps and avalanche zone plans require the level of clarification specified in Switzerland or France; terminology and definitions, often not used uniformly, can lead to ambiguities. Additional clarification of terms would help differentiate legislated versus noniegislated avalanche hazard mapping. 3. The maps used for avalanche hazard mapping are often too small to clearly specify hazard boundaries. Maps at a scale of 1:50,000 do not provide enough detail to be useful in land-use planning, where detail is critical. Thus, 1:25,000 is the minimum scale acceptable for general avalanche zone plans, while 1:10,000 to 1:2,000 is desirable for greater accuracy. 4. European nations with modern zoning plans invariably also carry out effective pro- grams of research in order to develop, calibrate, and modernize tools necessary for the definition of zone boundaries and the establishment of design criteria. No such research is currently supported in the United States. 5. A number of countries with avalanche problems have insurance coverage, with the French system in many respects the most novel. Insurance policies can be effectively used to support building regulations if individuals must meet required zoning and design specifications to qualitr for insurance. 6. Insurance systems demanding extreme or abnormal events, as in New Zealand and the U.S.S.R., serve a restricted if occasionally important role. The French definition of disaster conditions provides readily available protection to the public yet also provides the incentive to build in safe areas and to use adequate protection. 7. Comparison of the United States with other countries reveals that overall avalanche management has, at least in the past, been accorded some regional emphasis. Options that have not been adequately explored include avalanche insurance and land registry of avalanche-threatened property. It should also be noted that the current use of zoning strategy is subject to criticism, for it is carried out on an ad hoc basis rather than compre- hensively. These are aspects of avalanche management that would benefit from an overall strategy. Additional aspects are discussed in the next chapter.