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5 Loss Reduction Strategies A successful loss reduction program must be based on effective application of landslide information at federal, state, and local levels. While recognizing that significant improvements in our ability to mitigate landslide losses undoubtedly will be developed in the future, a wide range of effective loss reduction measures exist now. Out- reach programs and additional assistance measures are needed to help ensure that such loss reduction strategies are in fact used by state and local agencies and private entities. The major responsibility for employing loss reduction measures for any particular project resides with the person or entity actually develop- ing the project. All government units, including cities, special districts, counties, states, and federal agencies, have a responsibility to use appro- priate loss reduction measures when undertaking public projects. Most development, however, is undertaken privately. In these cases, it is up to the government agencies that approve private development to ensure that appropriate loss reduction measures are followed. Professionals in the field share this responsibility to use the most up-to-date mitigation mea- sures. The National Landslide Hazards Mitigation Strategy proposal (Spiker and Gori, 2000) acknowledged that a successful strategy must include a mitigation component and that mitigation activities are generally under- taken by state and local governments, private businesses, and individuals. The proposal notes that a range of mitigation measures exist including land-use planning and regulation, engineering, building codes, assess- ment districts, financial incentives and disincentives, emergency warn- 60
LOSS REDUCTION STRATEGIES 61 ing, and emergency preparedness but also points out that there are impediments to the use of such measures. It then proposes the following actions: 1. Evaluate the impediments to effective planning and controls on development and identify approaches for removing these impediments. 2. Develop an education program for state and local elected and appointed officials to sensitize them to the risk and costs of landslide hazards. 3. Develop and disseminate prototype incentives and disincentives for encouraging landslide mitigation to government agencies, the private sector, and academia. 4. Evaluate engineering and construction approaches to mitigate landslide hazards and develop a national plan for research to improve these techniques. 5. Encourage implementation of successful landslide mitigation tech- nologies. 6. Improve the ability to prepare for, respond to, and recover from landslide disasters. 5.1 IMPLEMENTATION OF LOSS REDUCTION MEASURES The loss reduction measures suggested in the National Landslide Hazard Mitigation Strategy proposal (Spiker and Gori, 2000), presented above, form part of the range of items that should be considered in a comprehensive national loss reduction program. These measures are described only briefly in the strategy proposal. The education and public awareness components of loss reduction are dealt with in the following chapter; here the committee's comments and suggestions related to the other loss reduction measures are presented. Section 5.2 discusses a number of additional measures that should be considered as components of a national loss reduction strategy, and a commentary on the informa- tion collection, interpretation, dissemination, and archiving components of the strategy can be found in section 5.3. Impediments to Effective Planning and Controls on Development. Although considerable information exists in some areas of the country with respect to landslides, in general, such information is not sufficiently known or used by local governments. In many cases, this is because nega- tive information (e.g., information concerning natural hazards) is not highly attractive to local elected officials and the development commu- nity. Considerable literature exists in the social science field that addresses these issues this literature must be assessed and the results employed in
62 PARTNERSHIPS FOR REDUCING LANDSLIDE RISK designing an effective outreach program. The Natural Hazards Center at the University of Colorado in Boulders is an important resource in this respect, making available a substantial library on natural hazards and human responses to such risks. The center also hosts an annual workshop attended by a broad spectrum of federal, state, and local officials involved in natural disaster mitigation; academic researchers; and representatives of professional and nongovernmental organizations. As noted earlier, most local governments do not have landslide haz- ard maps, and communities usually look to a higher level of government for mapping. In California, to comply with the Seismic Hazards Mapping Act, the state is preparing maps that identify areas subject to landslides and enhanced ground shaking. Prior to approval of a development project, cities and counties must require a geotechnical report on the subject property. In addition, property sellers or their agents must disclose infor- mation shown on these maps prior to property sale. Oregon has adopted similar legislation that specifically addresses fast-moving landslides (debris flows). This legislation directs the state to undertake mapping of landslide- prone areas and directs local governments to take actions to reduce potential damage from mapped landslides. Funding for this mapping pro- gram was provided by the Federal Emergency Management Agency's (FEMA's) Project Impact (FEMA, 2003~. In addition to these examples from California and Oregon, some other state geological surveys have carried out extensive mapping of geological hazards (e.g., Alabama, Colorado [see Box 3.6], Kentucky). As noted in Chapter 3, the substantial opportunities arising from high- resolution digital elevation mapping using LIDAR (Light Detection and Ranging) have prompted several states to undertake or propose partial or complete statewide LIDAR mapping programs. A nationally coordinated program to accelerate LIDAR mapping would provide significant assis- tance to local governments and make a major contribution toward land- slide hazard mapping. However, from a national perspective, state landslide hazard map- ping activities are severely restricted by the minimal funds available. Some federal assistance has been provided (e.g., U.S. Geological Survey [USGS] demonstration mapping, FEMA Project Impact support), but there is a clear need for additional funding for this activity. The payoff from such state-level funding comes in the form of enhanced awareness and mitigation at the local level. Conditions vary across the country, but a balance between USGS, state, and local mapping should be established for each state. States could then implement legislation to require that local iSee htip: / /www.colorado.edu/hazards/
LOSS REDUCTION STRATEGIES 63 governments take account of such information. In addition, guidelines could be developed and disseminated to assist states in their efforts to ensure that such maps are used effectively at the local level. Encouraging Landslide Mitigation for Government Agencies, the Private Sector, and Academia. Emphasis should be placed on developing and disseminating incentives for mitigation. Communities must be con- vinced that it is in their own best interest to avoid the effects and reper- cussions of landslide disasters. Materials should describe such repercussions, which can include loss of life, injuries, financial losses to the private and public sectors, and lawsuits. Examples of successful land-use planning approaches should be documented and distributed. In some instances, land-use planning may lead to development of landslide-prone areas being avoided while at the same time allowing increased development in stable areas as compensation. In other instances, high land values may call for expensive engineering solutions for unstable land. Outreach activities, either as hard-copy publications or web-based information, are needed to inform communities of the seriousness of development in landslide-prone terrain and the advantages of recognizing and realisti- cally dealing with the problem. Another approach is to establish disincentives in the situation where development may be allowed in spite of hazards. For example, a dis- incentive can exist where a community allows a development in a landslide- prone area with the provision that the developer must disclose to property purchasers that they are buying property with a potential natural hazard. Otherwise, the developer may be disinclined to plan properly and the purchaser, particularly if notified at the last minute, is often disinclined to call off the deal. It is important that this information also be available to financial institutions (mortgage and insurance providers) that may be stakeholders. Evaluation of Engineering and Construction Approaches to Mitigate Landslide Hazards and Development of a National Plan for Research to Improve These Techniques. Considerable information already exists that describes current engineering and construction approaches to miti- gating landslide hazards. This information must be assembled and ana- lyzed so that the major needs for the development of new engineering solutions to landslide problems can be identified. A specific research pro- gram could then be implemented to both improve existing techniques and develop new mitigation techniques. Analysis to determine if more effective and cost-efficient approaches can be developed would also be useful. In addition, new information continues to come from landslide experiences. This information should be analyzed to determine whether
64 PARTNERSHIPS FOR REDUCING LANDSLIDE RISK new engineering designs and practices are needed, and any such designs and practices should then be disseminated to the user community. In situations where legal liability issues might otherwise lead to a reluc- tance by industry to adopt new mitigation techniques, sponsorship and support of such techniques by government agencies may ensure more widespread application. Implementation of Successful Landslide Mitigation Technologies. This can be accomplished largely through dissemination, via a national infor- mation clearinghouse (see section 5.3), of model approaches and good case histories. It is necessary to convince state and local agencies that although they might potentially be affected by landslides, there are effec- tive ways to mitigate the hazard. This should be part of a coordinated outreach program undertaken as part of the national mitigation strategy. Improving the Ability to Prepare for, Respond to, and Recover from Landslide Disasters. Landslide disasters normally affect small areas, com- pared to the more regional effects of events such as earthquakes, floods, or hurricanes. Nonetheless, they can cause major disruption in the affected and immediately surrounding areas. Accordingly, geologists, engineers, and emergency response professionals must be trained to understand the likely problems associated with a landslide, the emergency response that may be necessary, and the potential longer-term reconstruction needs. The full range of public utilities must be included in such preparation. Although such education and training should be included in the normal disaster plans and training programs at the local level, there is an impor- tant role for the national mitigation strategy to encourage such efforts and make available supporting materials. 5.2 ADDITIONAL LOSS REDUCTION MEASURES The USGS proposal (Spiker and Gori, 2000) recognized and was responsive to many issues related to loss reduction activities; however, several additional areas should be addressed. Standards of Care for Landslide Mapping and Engineering. Local regu- lations not only must require detailed landslide hazard mapping, but must ensure that the quality of hazard mapping meets appropriate standards of care. Such standards for hazard mapping and interpretation must be spelled out in local regulations, and the maps and reports prepared on behalf of a developer should be peer-reviewed by a qualified geologist on behalf of the jurisdiction. Finally, the actual grading and construction must be approved by both the preparer and the reviewer of these reports and
LOSS REDUCTION STRATEGIES 65 plans. These standards of care are necessary to ensure that the final prod- uct meets the approved design. Institutionalization of such requirements in local regulations will help ensure that geological hazard mapping is used effectively. Model standards of care should be developed as a com- ponent of the national strategy to assist in the administration of local regu- lations, and an ultimate goal of partnership activity in this area would be incorporation of model standards of care into the Uniform Building Code and other building codes. Linking Hazard Mapping to Land-Use Planning. Land-use planning approaches at the local level consist of general plans, zoning regulations, and subdivision regulations. Mapping, even at the standard USGS topo- graphic map scale (1:24,000), can be useful to a community in helping shape its general plan for future development. Major areas of potential instability can be identified as needing special investigations or, in some instances, designated for open space use. In extreme conditions, general plans may propose cluster development in which construction is limited to stable areas and unstable areas serve as open space attendant to the development. The creative use of geological hazard information in pre- paring general plans, however, depends on a staff that has had training in the application of geologic information to plan making. Recognition that there are often negative implications from the identification of landslide- prone areas, in the form of decreased valuations, emphasizes the impor- tant support role that nationally accepted standards of practice have for staff at the local level. Local zoning regulations stipulate, usually in great detail, how land can be used. Some communities have developed landslide matrices that are included in the zoning ordinance or as an adjunct to the ordinance. These matrices correlate categories of land stability with permitted or recommended land uses; they reflect a certain level of risk that the com- munity has accepted. Two examples of this system occur in Morgan Hill and Portola Valley, both in California (Spangle Associates, 1988; Morgan Hill, 1994~. A similar approach, although not incorporated in zoning, was prepared for the Portland, Oregon, regional government (DOGAMI, 1998~. In some cases, not only are land uses identified, but they may be tied to general building types. Somewhat similar approaches have been applied in other parts of the country (e.g., Cincinnati, Ohio; see Box 1.3~. It is at the subdivision stage (neighborhood zonation maps, see Box 3.2) that the future pattern of ownership and land use is firmly established. It is at this stage that a community must demand the most detailed informa- tion about geologic hazards. The preparation of subdivision regulations that address geologic hazards is not complicated a more difficult task is to ensure that the regulations are properly administered. In addition,
66 PARTNERSHIPS FOR REDUCING LANDSLIDE RISK elected officials have to be convinced of the need for such regulations, and there must be both an administrative process and a staff capable of imple- menting the regulations. Guidance and assistance, in the form of publica- tions and effective outreach, should be provided to local governments as part of the national strategy outreach, so that they are better able to incor- porate landslide mitigation provisions into their general plans, zoning regulations, and subdivision regulations. Protection of Existing Development. Unfortunately, many urban areas were developed prior to the adoption of good hazard mapping and review practices in landslide-prone areas. Each year, the news media report cases in which houses are damaged due to differential settlement, lost in land- slides, or in the worst cases, destroyed by debris flows. Although most of these cases result in financial losses, in the case of debris flows the results are often much more catastrophic and can include loss of life. For devel- oped landslide-prone areas, the developers have left the scene in most cases and property owners face the prospect of potentially or actually losing their homes. The problems for governments when landslides impact government property are less serious than for homeowners, since the loss usually represents a small fraction of a government's assets. However, with private property the loss can represent most of the owner's assets. It is in this area that governmental assistance is needed. Landslide Insurance. Landslide insurance could potentially provide a financial mechanism for spreading the costs of addressing or recovering from landslides among broad categories of those at risk, while also being linked to incentives for reducing risks. Costs arising from landslides are already a significant charge to insurance companies as those affected by landslides engage in litigation to determine fiscal responsibility for remediation costs. Landslide insurance is not presently offered because of the "adverse selection" of potential policyholders (Olshansky, 1996~. That is, without mechanisms for expanding the pool of policyholders, only those who are at greatest risk would purchase policies, making it finan- cially infeasible to offer insurance. In addition, landslide loss records are insufficient for establishing risk-based rates for landslide insurance. These problems are similar to those associated with establishing a viable pro- gram for earthquake insurance. The National Flood Insurance Program (NFIP) has often been cited as a model that could be applied to landslide hazards, and in fact there have been instances in which the NFIP has covered damage caused by mud- slides. In this program, the federal government produces maps of areas that are subject to flooding across the nation. In order for local govern- ments to have properties in their jurisdiction eligible for the NFIP, they
LOSS REDUCTION STRATEGIES 67 must adopt local ordinances to ensure that losses from flooding will be minimized. The same type of requirements for cities and counties would be needed for landslide insurance. Another potential insurance approach would be to include landslide hazards into an all-hazard residential risk insurance program, as is the case for homeowners under New Zealand's governmentally subsidized natural disaster insurance program (Box 5.1) which covers earthquakes, landslides, tsunamis, and other natural haz- ards (Earthquake Commission, 2003~. It is important to recognize that loss- sharing mechanisms such as insurance are only a means for spreading the financial burden of landslides; they accomplish nothing themselves in terms of reducing risks. However, if mitigation measures are required as conditions for insurance, they can result in significant loss reduction. Accordingly, losses arising from landslides should be incorporated into any future national program of disaster insurance as long as such a pro- gram includes encouragement of or requirements for landslide mitigation measures. Assessment Districts and Homeowner Associations. At least two addi- tional types of financial arrangement special assessment districts and homeowner associations are worthy of consideration for addressing landslide hazards. Both can provide financing for remedial actions prior to or in the aftermath of landslides. Special assessment districts are political jurisdictions created by state legislation for the purpose of taxing residents of those districts in order to carry out designated functions. California, for example, has statutory provisions that enable creation of Geological Hazard Abatement Districts. Another vehicle for remedial action is through homeowner associations. The covenants and conditions that govern the association can provide for assessments to care for areas that fail due to landslides. This can be critically important because in many developments, the homeowner association actually assumes the responsi- bility for maintenance of major areas and facilities that are owned in common by the association. 5.3 INFORMATION COLLECTION, INTERPRETATION, DISSEMINATION, AND ARCHIVING The proposed National Landslide Hazards Mitigation Strategy incor- porates a plan for information collection, interpretation, dissemination, and archiving (Spiker and Gori, 2000~. The objectives of this component of the strategy are the following: · Evaluate and use state-of-the-art technologies and methods for the
68 PARTNERSHIPS FOR REDUCING LANDSLIDE RISK dissemination of technical information, research results, maps, and real- time warnings of potential landslide activity. · Develop and implement a national strategy for the systematic collection, interpretation, archiving, and distribution of this information. The proposed national strategy will collect a large quantity of infor- mation that must be interpreted correctly and translated into usable products, and then effectively disseminated to users. The information must also be archived in a manner that will permit ease of access by inter- preters and users at all levels and also will ensure permanent future access. The types of information to be collected and archived will include:
LOSS REDUCTION STRATEGIES 69 reports; · digital information, including images, maps, and reports; · nondigital information, including hard copies of maps and images; · nondigital technical research, loss estimation, and implementation · Information from real-time monitoring; · weather information and hazard alerts; and · manuals, videos, and other training materials. The committee offers the following comments on specific items in the plan to assist with the development of detailed implementation strategies. Information Collection. An extensive program of information collection
70 PARTNERSHIPS FOR REDUCING LANDSLIDE RISK is essential for the development of maps and other interpretative products for hazard mitigation. Much of the information will be aerial photographs or electronic imagery from which high-accuracy topographic, geologic, and landslide inventory maps can be compiled. The proposed program anticipates that many workers will be involved in information collection, including USGS scientists, personnel from other federal agencies, per- sonnel from state geological surveys and agencies, university researchers, and private consultants. Effective coordination is required to ensure that the most important information is collected, archived, and made available using efficient and high-quality procedures. In all cases, digital geospatial data should have associated metadata in accordance with Federal Geo- graphic Data Committee (FGDC) guidelines (Box 5.2), as a component of the National Spatial Data Infrastructure (NSDI). Interpretation of Information. Information must be interpreted by trained scientists and engineers. At the national level, scientists and engineers with the USGS and other federal agencies will have lead responsibility for collection and interpretation of information. At the state level, scientists and engineers in state geological surveys, highway departments, emer- gency response units, and other agencies will take the lead in preparing interpretive products. Contracts with universities and private companies should be used to expand the resource pool of qualified data collectors and interpreters. The products at the state level, however, will be devel- oped for use at the local level by counties, cities, transportation and utility districts, and so forth. In many instances, local agencies will have to adapt or develop interpretive products for their specific application. Local per- sonnel must to be trained to ensure that these products are interpreted and applied correctly, as well as widely used for hazard mitigation (see Chapter 6 for additional discussion). Dissemination of Landslide Hazard Information. Because implementa- tion occurs primarily at the local level, dissemination of data and infor- mation to the local level is a key element of the program. To ensure that dissemination occurs and that those receiving the information are able to interpret and apply the products, effective cooperative partnership pro- grams must be developed between federal, state, and local partners. To provide incentives for local users to participate, a program of local grants and cost-sharing is needed. At present, the Federal Highway Administra- tion has programs for disseminating technical information and providing financial aid to states in applying that information, and the USGS National Landslide Information Center has an active program for distributing land- slide information to the public, researchers, and planners and to local, state, and federal agencies. The national strategy should contain a pro-
LOSS REDUCTION STRATEGIES 7 BOX 5~2 FGDC AND THE NATIONAL SPATIAL DATA INF~TRUCTURE he Federal Geographic Data: Commidde (FGDC) is ~ federal inter agency commode responsible for facilitating and coordinating the activities of the National Spatial Data Infrastructure (NSDI). The NSDI encompasses pal iciest standards, and procedures for organizations to cooperatively produce and share geographic data:. The 19 federal agencies that make up the FGDC are developing the NSDI ire cooperation with organizations from stab, local, and tribal governments, the academic commonly add the private sector. The NSDI jar relevant to any agency that collects, produces, acqu!ms' ma:!n~ins' distributes, uses' or presewes analog or digital spatial data' including all geographic ir,ffirm~ion Am activities, that am financed directly or indirectly, in whole or in park by ~dera:l funds. Deferent federal agencies have lead responsibilities for the various spatial data themes E.g.' U5G5 is responsible for all geologic mapping Information and related geoscience spatial dead. Lead agencies are required populate each da a theme' priacipa:lly by development of partnership programs with stays, tribes', academia, the private sector', and other federal agencies, and also tO facilitate the development and implementation of FGDC standards for each theme. To build and supped the NSDI, any agencies that collect, use, or dis- seminam geographic information angler carry out related spatial data activliles are required ~ do the Allowing' both internally and thmugh their activities involving partners' gravity and contract · Develop a strategy for adv~anc~r~g geographic information and related spatial data activities appropriate ~ their mission . Collect' maintain, d~ssemi Ate' and preserve spatial i affirmation such that the resulting days information, or produce can be shared readily with other federal agencies and r,on-fdderal users. . Allocate agency resources to fulfill the responsibliltles of efflct!ve spatial data collection' p~duct~on' and stewardship. · Use FGDC data standards, FGDC Content $tanda:rds for Digital Geospatj~l Metadata', and other approprjam standards' document spatial data with the relevant metada~, and make metadata available on-line through a mgismred NSDI-~ompat~ble clearinghouse node. · C ordinate n d work In padaership with federal' stab, tribal and local government agencies academia' and the private sector to ~'cjently and cost-effectively collect:; integrate, maintain, disseminate, and pre$ewe spatial data', building upon local data wherever possible. · $uppod emergency response activities requiring spatial dam in accor- dance with provisions of the Sword Act arid other governing legislation. · Search all sources, including the National Spatial Da fig house,, ~ de~rm~ne If existing federal,, stay, local,, or pri~vate~d~ata~me~et~ agency needs before expending funds for dam collection.
72 PARTNERSHIPS FOR REDUCING LANDSLIDE RISK gram of partnerships and cost-sharing between each of the federal agen- cies and their state counterparts, combined with effective education and training programs, to ensure that information is disseminated and applied at the user level. Archiving of Information. Repositories will be required to archive the data and make it accessible to all potential users. As much information as possible should be stored in digital format and made accessible through web sites. There should be a central point of contact, probably most effi- ciently managed through expansion of the existing National Landslide Information Center, with links to distributed data centers. Each state could provide links to these distributed data centers on state government sites, with emphasis on material most useful for its personnel and local user communities. Federal and state departments of transportation could include links to the central and distributed repositories of landslide infor- mation on their web sites. In effect, the primary national source for data and information would be a web-based national information clearing- house. Digital images, digital data files, interpreted maps, and many other useful materials will be stored in these web sites, which should be inter- linked to allow ease of access by users at all levels of interest. In addition to the web sites, archival libraries will be needed at the national and state levels to store nondigital documents and historical images. The USGS could locate regional landslide data repositories at each of its regional libraries, and each state geological survey or other lead agency participat- ing in the program should secure a special section in its state library for archiving landslide information. These collections of archived informa- tion should be made readily available to users at all levels.