AbstractThe authors proposed an institutional and technical framework for preparation, planning, design, construction, and maintenance for road geohazard risk management in developing countries. As technical assistance in this area is an urgent issue, a universal framework for managing risks in road geohazards, such as sediment flows and flash floods, needs to be proposed. To this end, the best practices of road geohazard risk management in the world have been examined and analyzed from technical and institutional perspectives. This paper aims to discuss the universal applicability of the proposed institutional and technical framework to different countries that are at different stages of development. The proposed framework comprises the stages of (1) institutional capacity and coordination, (2) systems planning, (3) engineering and design, (4) operations and maintenance, and (5) contingency planning. The framework can be put in place in a step-by-step manner depending on the capacity and financial constraints of the project-implementing countries. The technical validity of the framework was confirmed with the cooperation of The World Bank’s Task Team Leaders and other experts in the field of transport and disaster risk management. Finally, case studies in Brazil and Serbia were conducted to verify the applicability of the framework.IntroductionBackgroundDisasters have affected billions of people, in particular, the poor and vulnerable in developing countries. Since 1980, more than two million people and over $3 trillion have been lost to disasters caused by natural hazards. The total damages have been increasing by more than 600% per year, from $23 billion a year in the 1980s to $150 billion a year in the last decade (World Bank 2019). Kikuchi et al. (2015) evaluated 445 disaster prevention projects funded by the Japanese government, focusing on the number of reduction effects of death, and the world disaster-related funding since 1990 was analyzed by the same evaluation indicator. The funding for preparedness contributes to reducing the number of deaths, and the financial assistance, which is placed fifth in terms of the total amount of funding, is the main factor in terms of death toll reduction. Japanese funding is highly evaluated to give priority to investing for the promotion of prevention and preparedness.The Japan-World Bank Program for mainstreaming disaster risk management was started in 2014 with funding from Japan to share knowledge, expertise, and technology with developing countries in order to give priority to disaster risk reduction (DRR) (World Bank 2018). DRR is a broad term that includes anything we do to prevent or reduce the damage caused by natural hazards like earthquakes and floods. Since developing countries lack sufficient funds and knowledge to implement full-scale disaster prevention measures, this program will enable each country to mainstream disaster prevention in national development plans and infrastructure investment programs depending on the capacity constraints of the country. It was pointed out that there is a need for a mechanism to effectively and efficiently implement DRR. In addition, it was required to convey necessary institutional and technical know-how in an understandable manner for policy makers and practitioners in national and local governments.In developing countries, there is a high demand for the development of transport infrastructure, which is the basis of national and regional socio-economic activities. Whenever they are acting as a connection to crucial services during emergency situations, transport linkages are critical to disaster risk management. Strategically planned transport systems are foundational to the resilience of urban and rural residents (World Bank 2017). In particular, since there are enormous needs for highway development, disaster risk countermeasures should be put in place at each stage of planning, implementation, and management in order to mainstream disaster prevention in highway projects in developing countries. One of the major natural disaster risks in the road sector would be road geohazards, which is defined as “events caused by geological, geomorphological, and climatic conditions or processes that represent serious threats to human lives, property, and the natural and built environment” (Solheim et al. 2005). The authors have targeted road geohazards for this study, in which disaster risk countermeasures will be examined, and a framework for road geohazard risk management will be proposed.An institutional and technical framework contributing to DRR will be proposed through a review of best practices for disaster prevention measures in the world. Development of the framework will be phased in stages according to the capacity and financial constraints of developing countries. The framework will be utilized to mainstream disaster prevention in the road sector in developing countries and to construct a mechanism for effectively and efficiently implementing measures against disaster risks.Literature ReviewApproaches to mainstream DRR in developing countries and frameworks for disaster risk management in the transport sector are found in the following cases. Asian Disaster Preparedness Center and Department of Disaster Management (Bhutan) (2014) developed a policy recommendation on numerous options for mainstreaming DRR into the road and bridge sector in Bhutan. These options include the use of disaster risk assessments during the construction of new roads as well as the use of natural hazard risk information in land use management. It is indicated that the consideration of hazard and risk information at the early stages of the project management process can lead to long-term savings, both in terms of the initial cost of the project and the cost of maintenance operations over the life of the infrastructure. This is because investment in the mitigation and management of risk has generated high economic rates of return.World Bank (2015) proposed an analytical framework for mainstreaming resilience in transport systems. This framework addresses the three key levels when identifying problems in a transport system and planning, designing, and evaluating transport projects. Those levels are temporal dimensions, transport management domains, and principles of resilience. The temporal dimensions are the three key stages: predisaster risk assessment and management, emergency response and risk reduction, and postdisaster recovery and reconstruction. Transport management domains introduced for resilience are policies, institutions, and processes; expertise; financial arrangements and incentives; operations and maintenance; and technical planning and design. Nine principles of resilience including safe failure, redundancy, and good governance are introduced across these domains and stages to measure resilience in transport systems. World Road Association (2013) compiled a technical report on risks associated with natural disasters, climate change, man-made disasters, and security threats for highway management and operations. This work focuses on four key areas: (1) step-by-step user guide to assist road authorities in evaluating risks associated with all hazards; (2) practical techniques for managing risks associated with natural disasters; (3) case studies documenting a step-by-step user guide to assist road authorities in reducing or mitigating risks; and (4) a proposed web-application Risk Management Toolbox.Park et al. (2013) proposed risk and resilience approaches integrated into catastrophe management in engineering systems, in which resilience can be defined as the capability of systems to anticipate and adapt to the potential for surprise and failure. They argue that resilience is better understood as the outcome of a recursive process that includes sensing, anticipation, learning, and adaptation. In this approach, resilience analysis can be understood as differentiable from, but complementary to, risk analysis with important implications for the adaptive management in the engineering systems. Meyer et al. (2012) argue that most transportation asset management plans do not currently detail the specific causes of failure. Any hazard that affects the condition, performance, and life of the asset and its ability to provide a reliable and safe service will influence the timing of rehabilitation and replacement. They concluded that risk ratings or vulnerability indicators can be included in an asset-management database, which could be gathered by engineering surveying, to enable agencies to quickly determine where to target adaptation actions.As a result of the literature review, despite the frequency of natural hazards and the threat of more extreme weather as a result of climate change, there are few works on how a systematic approach can be established to address natural disaster risks in the transport sector. To the best of the authors’ knowledge, no studies have been done on comprehensive risk management frameworks for particular risk hazards to mainstream DRR in the transport sector in developing countries.Study MethodologyThis study aims at proposing an institutional and technical framework for preparation, planning, design, construction, and maintenance for road geohazard risk management. A technical skill is required to implement effective road disaster prevention measures because it is difficult to assess risks in the road geohazard (e.g., debris flows, sediment flows, and flash floods). In other words, it is difficult to identify the likelihood and consequence of such risk occurring. As technical assistance in this area is an urgent issue, a universal framework for managing risks in road geohazards needs to be proposed. The best practices of road geohazard risk management in the world including Japan have been analyzed, and a technical framework examined the following areas: (1) responsibility and role-sharing between central and local governments, (2) laws and regulations on geohazard disasters, (3) disaster risk management plan, (4) countermeasures and investment plan, (5) implementation of structural and nonstructural measures, (6) inspection, survey, and management of road geohazard disasters, (7) risk calculation and index for DRR investment, (8) advanced technology for nonstructural countermeasures, and (9) emergency response/recovery/reconstruction.Depending on the capacity and financial constraints of the project-implementing country, it will be possible to gradually manage road geohazard risks through the proposed framework. The framework was devised so that simple/low-cost technology or high-cost technology could be selected. Furthermore, the technical validity of the framework was confirmed with the cooperation of The World Bank’s transportation experts and other experts in the field of disaster management. Finally, case studies in Brazil and Serbia were conducted to verify the applicability of the framework.Framework for Road Geohazards Risk ManagementThe road geohazard risk management approach proposed in the study aligns with the practices in the ISO 31000 standard (ISO 2018). It is indicated that “the risk management process involves the systematic application of policies, procedures, and practices to the activities of communicating and consulting, establishing the context and assessing, treating, monitoring, reviewing, recording, and reporting risk,” as illustrated in Fig. 1. Road geohazard mitigation measures fall into two broad categories: (1) proactive, applied before a disaster; and (2) response and recovery, applied after a geohazard event to manage secondary damage and recovery. For the former, road geohazard risks against the probability (or likelihood) of disasters and consequence (or impact) of occurrence need to be assessed. The management of such risks can be integrated into all phases of the infrastructure’s lifespan: ensuring risk-informed designs, engineering resilient infrastructure, managing existing assets, planning for emergencies, and building partnerships to improve transportation infrastructures for the future. The risk management methodologies are further discussed in Section 3 from institutional aspects.The World Bank’s approach to proactively manage the risks of disasters and hazards for resilient transport is to consider the entire life-cycle of the infrastructure from system planning, engineering and design, operations and maintenance, and contingency programming, as shown in Fig. 2 (World Bank 2017). In addition, insufficient knowledge and capacity to implement disaster prevention measures should be addressed in the context of low- and middle-income countries. Therefore, a proposed road geohazard risk management plan is composed of the following stages: •Institutional capacity and coordination cover the institutional arrangements that are necessary for the successful implementation of geohazard management.•Systems planning covers the systems planning aspects pertaining to the identification, assessment, and evaluation of risks, along with raising awareness of disasters.•Engineering and design deals with the engineered solutions to address geohazard risks, giving examples of different solutions to particular risk types.•Operations and maintenance focuses on the operation and maintenance aspects of geohazard management—whether through the maintenance of previously engineered solutions or the nonengineered solutions available to mitigate the impacts of geohazard risks.•Contingency programming addresses contingency programming issues, such as postdisaster response and recovery, and the important issue of funding arrangements.For most countries, there are significant opportunities to enhance the existing means of geohazard management, covering all stages of the life-cycle, as shown in Table 1.Table 1. Opportunities for enhancing road geohazard risk management by life-cycle stageTable 1. Opportunities for enhancing road geohazard risk management by life-cycle stageStageInstitutional aspectTechnical aspectSystems planning (instrumental setup)•No or insufficient laws, regulations, or technical standards, including assignment of responsible organizations•No or insufficient national or subnational government plans or strategies•No or insufficient mechanism, funding•No or insufficient expertise, or lack of essential data, for road geohazard risk management (such as historical weather data and disaster records)•No or insufficient risk evaluation practicesEngineering and design•No or insufficient mechanisms or funding for proper design and construction•No or inappropriate highway and risk management planning•No or insufficient engineering investigation for design•Lack of proper design and constructionOperations and maintenance•No or insufficient mechanisms or funding for proper nonstructural measures or for operations and maintenance responses•No or insufficient mechanism and system [staff, machinery, equipment, asset management information system (AMIS), information gathering and communication systems, guidance manuals, training, coordination, and partnership system] for nonstructural measures•Weak or nonexistent domestic road maintenance contracting industryContingency programming•No or insufficient mechanisms or funding for proper postdisaster response and recovery•No or insufficient contingency planning for both technical and physical response to events, including intelligent transport systems (ITS) and related AMISRoad geohazard risk management entails three main elements covered by the framework: (1) institutional setup, (2) road geohazard risk management for new roads, and (3) road geohazard risk management for existing roads. An adequate institutional framework is a necessary condition to guarantee proper road geohazard risk management, whose activities typically follow the road project management stages of preconcept, concept, design, construction, and operation and maintenance. The road geohazard risk management processes for new and existing roads differ only in the risk assessment and geohazard risk management planning stages. The measures common to both new and existing roads include (1) proactive structural measures, (2) proactive nonstructural measures, (3) postdisaster response, and (4) recovery. The proposed road geohazard risk management framework is summarized in Fig. 3. The framework is characterized by institutional and technical approaches that are applicable to developing countries. It is designed for application across all road types and road hierarchies. The World Bank disseminates the road geohazard risk management framework by compiling details of its techniques and practices into a handbook. The subsequent chapters will discuss concrete measures followed by recommendations on how techniques and practices in the framework can be applied to the developing world.Institutional Capacity and CoordinationInstitutional Setup and Asset ManagementWithout an appropriate institutional setup, within which the geohazard risk management tasks are implemented, there is little chance of a successful outcome. The institutional setup covers two primary aspects: •Institutional framework, such as the appropriate laws, regulations, and technical standards to enable geohazard management•The appropriate capacity and capability of human resources to deliver an appropriate geohazard risk management program.While the underlying laws, regulations, and technical standards may be largely the same from country to country regarding the need to manage the road network safely and efficiently, the amount of human capital expended on geohazard management will reflect the relative risk exposure in each country (or part of a country). For instance, a road authority managing a road in a mountainous country with high rainfall will reasonably be more concerned about geohazards and hence invest more time and effort in their management.This study is intended to put geohazard risk management in place within national governments, road agencies, and local authorities managing road infrastructure. In the majority of countries, road assets are financed by the government budget, and managing costly road assets requires a systematic approach, which assures an adequate decision in each step of the project life-cycle, namely planning, designing, building, and managing. The importance of efficient infrastructure asset management is significantly increasing. As defined by the AASHTO, “Transportation Asset Management is a strategic and systematic process of operating, maintaining, upgrading, and expanding physical assets effectively throughout their life-cycle. It focuses on business and engineering practices for resource allocation and utilization, with the objective of better decision making based upon quality information and well-defined objectives” (AASHTO 2016).Geohazard management activities must fit within the road authority’s overarching asset management framework, as shown in Fig. 4. For some developing countries that have incorporated road asset management practices into the project life-cycle, it would not be difficult for these countries to put road geohazard risk management in place with the financial and technical support of international organizations and developed countries. For developing countries that have not yet started road asset management, most road geohazard risk management activities can correspond with the traditional management processes in the road authorities.Institutional FrameworkAn integrated and effective institutional setup is required to promote a systematic and efficient approach to road geohazard risk management. The institutional framework comprises (1) laws, regulations, and technical standards; (2) national and subnational government plans and strategies; and (3) mechanisms for implementation.Laws, Regulations, and Technical StandardsGovernments may or may not have laws, regulations, and technical standards that govern road geohazard risk management. If they exist, the laws and regulations stipulate the responsibility and authority of the actors involved, such as road management authorities and traffic police, to ensure the implementation of road geohazard risk management.National and Subnational Plans and StrategiesThe development of national and subnational plans and strategies is essential to promote proper road geohazard risk management, and therefore, such development is an essential target of national and subnational governments. When national governments formulate development plans and strategies, the management plan for road geohazards must be incorporated as well. The government or road management authorities also formulate specific investment programs and projects to support geohazard risk management.Mechanisms for ImplementationBecause geohazard management is part of the road authority’s overall management activities, the organizational structure will not be determined solely by geohazard management risk requirements. The recommended practice is that geohazard risk management is fully integrated into every practice of the organization.In terms of implementation mechanisms in developing countries, limited capacity for disaster risk management at the local level is a common challenge. National governments have various roles to support local governments, who have the primary responsibility in disaster risk management, to prepare for and respond to disasters. Similarly, local offices in the road authorities are in a position to be the first responder. It might take some time for road authorities to accumulate experience and develop institutional and technical capacity at the local level. Delegation of responsibilities and decision-making authority to a lower organizational level would be required at a certain point to promote road geohazard risk management (Asian Development Bank Institute 2013).Institutional Capacity ReviewOne of the most important aspects of geohazard risk management is the institutional capacity review, which measures how the road authority addresses geohazard risk and risk mitigation at the national and subnational levels, considering the following aspects: •Existence and level of maturity of the legal framework, institutions, and plans or strategies•Institutional capacity and capability•Implementation level of plans or strategies•Situation and effectiveness of projects on road geohazard risk management.Results of an institutional capacity review reach an official consensus on weaknesses, targets for institutional strengthening, and investment priorities and their financing strategy.The authors propose three step-up targets on road geohazard management. First, essential targets are the initial requirements for instituting road geohazard risk management and setting up road geohazard management. Second, intermediate targets are the next level of requirements to operationalize road geohazard risk management. Finally, advanced targets enhance road geohazard risk management through more rigorous review, elaboration, and enhancement using advanced technologies. Each government reviews its institutional capacity and budget constraints and sets a target as a first step. Examples of the items and activities of each target are shown in Table 2.Table 2. Setup targets for strengthening road geohazard risk managementTable 2. Setup targets for strengthening road geohazard risk managementAspect of road geohazard risk managementEssentialIntermediateAdvancedLaws, regulations, and technical standardsFormation of key laws and regulations pertaining to responsibilities for road geohazard management and responseReview and updating of laws and regulationsFurther review and updating of laws and regulations, including the contribution of the road function subnational geohazard managementFormulation of technical standards and guidelinesRisk evaluationStarting with the basic method of risk evaluation (such as simple risk qualitative evaluation, using multiple criteria)Review and updating the immediate method of risk evaluation (for example, risk-level rating)Further review and updating the advanced method of risk evaluation (for example, economic risk evaluation as potential annual loss)Structural measuresConstruction of fundamental structural measures (for example, earthworks and surface drainage)Construction of common structural measures (for example, standard retaining walls)Adaptation of advanced structural measures for higher-magnitude geohazardsNonstructural measuresEstablishment of fundamental measures (for example, routine patrol and monitoring)Enhancement of nonstructural measures (for example, precautional road closure arrangements)Further enhancement (for example, a road geohazard early warning system using ICT)Postdisaster response and recoveryPreparation and fundamental practice for a postdisaster response, including preidentification of responsibilities and budgets to address geohazard eventsEnhancement of postdisaster response, including formalized plans to address specific geohazard eventsFurther enhancement of postdisaster response and recovery (for example, formation and training of special task force for wide-area severe geohazard event)National road authorities formulate institutional, technical coordination, and funding mechanism for the efficient implementation of road geohazards risk management. When setting up targets in developing countries, it should be noted that limited capacity at the local level must be taken into consideration. The checklists for institutional capacity review added to the annex of the handbook would help developing countries to assess the current capability. Knowledge and insight are required to identify and recommend ways to address any deficiencies between the assessed and target competencies. Governments of developing countries must have a thorough consultation with experts and leaders as well as institutions and stakeholders to set targets for each item where the target capability is above the current assessed capability.Systems PlanningSystems PlanningThe systems planning stage covers those activities that are necessary to be in place to support the overall geohazard risk management process. It comprises two main aspects: Risk evaluation and risk management planning. Although the geographic scope of any geohazard risk evaluation will inherently be different between studies on existing roads or potential new-road alignments, the underlying methods are the same. For existing roads, the approach may be constrained to a single site, a single road, or expanded to the entire network of roads. For new-road alignments, the approach needs to ensure full coverage of all potential road alignments.For existing roads, the outcome of the geohazard risk evaluation is to develop a prioritized list of sites for subsequent mitigation. For new-road alignments, the risk evaluation process should ensure that there is a basis for proper planning to avoid cost overruns, construction delays, and costly operation and maintenance outcomes. The workflow for risk evaluation of geohazards consists of two steps: (1) identification and mapping of geohazards; and (2) assessment of geohazards.Risk EvaluationDepending on the capacity and financial constraints of the project-implementing country, the authors proposed three options for identification and mapping of geohazards and assessment of geohazards:Identification and Mapping of GeohazardsBasic MethodThe road maintenance staff identifies any abnormality or deformation of the road by using their maintenance experience, on-site visual inspections, and information provided by road users.Intermediate MethodGeotechnical engineering experts conduct an identification survey of hazard-prone road locations by collecting data of historical geohazard damage events and screening hazard-prone road locations via on-site observations.Advanced MethodEngineering geology experts conduct detailed hazard mapping along with the intermediate method. The detailed hazard map to identify hazard-prone locations is prepared through the analysis of contour maps, and interpretation is conducted using either aerial photographs or satellite images.The fundamental principle is that experienced road authority staff investigate and monitor hazards through routine maintenance. In developing countries, there are few or no road authority staff with experience in inspecting geohazards and abnormalities. There is no other choice but to gain this experience at the local level since the staff members are responsible for activities and decision making on risk management. In the meanwhile, there is no problem with outsourcing identification surveys to fill out inventory sheets for each hazard-prone road location. Detailed hazard mapping would be conducted depending on the available funds and risk level. It is important that executive officers periodically check inventory sheets, including (1) location type; (2) simple observation results; and (3) sketches and photographs, to prevent overlooking potential road geohazard risks.Assessment of GeohazardsIn principle, new-road planning aims to ensure that the true long-term costs of the different alignments are appropriately assessed, which typically results in avoidance of high-risk hazardous locations. In contrast, for existing roads, risk evaluation and planning is intended to ensure that funds to mitigate risks are appropriately prioritized and that contingency plans can be put in place. Three options for assessment of geohazards are proposed:Basic MethodFor the initial assessment, rather than undertaking a quantitative evaluation of both the likelihood and consequence of a risk event occurring, a simpler qualitative evaluation may be used. Likelihood may be defined in terms of occurrence probability, for example: low (more than 20 years between failure events), medium (5–20 years between failure events), and high (less than 5 years between failure events). A consequence may be defined in terms of the duration and magnitude of damage, for example, low (would not cause a loss of human life or significant safety issues), medium (may have an impact on human life), and high (could have a significantly negative impact on human life).Intermediate MethodThis approach builds on the basic method. The risk rating of an endangered road location is calculated by evaluating the likelihood and magnitude of damage on a number of subcategories, with a score assigned to each. These scores are then multiplied to generate an overall score of the risk level.Advanced MethodA risk index is calculated as a potential annual economic loss. The potential annual economic loss is the result of the integral computations of the economic losses of several extents of road damage and their probabilities. This index is useful for understanding, from an economics perspective, the prioritization of studies for those measures among different hazard-prone road locations. Its biggest advantage as a risk index is that it can be used for the benefit estimation of investments for road geohazard risk management, which in turn is used in the cost-benefit analysis.The governments of developing countries would tend to take a reactive approach by retrofitting existing roads after disasters. While the countermeasures against natural disasters seem costly, the investment pays off. There is a lack of understanding of the importance of investing in the promotion of proactive disaster prevention. Assessment of geohazards is a critical part of road geohazard risk management in terms that objective evaluation is used as the basis for the budgetary provision required for structure and nonstructure measures. The budgeting process in the governments of developing countries being based on evaluation results would lead to a better understanding that funding for preparedness and prevention contributes to reducing the amount of damage caused by disasters (Inter-American Development Bank 2017).Risk Management PlanningRisk management planning requires recognizing, understanding, and addressing all potential risks, which are identified and assessed in the risk evaluation process, to prioritize hazard-prone road locations for the subsequent application of risk mitigation measures (Amarjit 2017). Although the techniques for risk management planning vary from country to country, the underlying methods are the same. In the framework, network-level analysis and project-level analysis, either of which can be applicable to most developing countries, are proposed to prioritize the roads for investment. In the subsequent paragraphs, project-level option selection will be discussed to illustrate the decision-making process for specific solutions at specific locations.There is a need for proper investment of time and money in project-level option selection. The first stage in selecting the preferred option is to define the evaluation approach. Typically, for existing roads, the different options can be compared using life-cycle cost analysis on the presumption that each option will broadly offer the same benefits to road users, and the decision is primarily a technical one as to which solution can be delivered for the lowest cost. The life-cycle costs include the initial investment costs of each option, along with the corresponding annual maintenance cost. The evaluation period for determining the life-cycle cost should align with established practices within the road authority, which typically range between 15 and 50 years. Where no guidance is provided within a country on the period to analyze, a good approach is to consider the life expectancy of the longest-life option.For new-road alignments, the decision will typically involve multiple factors, including many nongeohazard factors such as cost (initial construction and ongoing maintenance), safety, social and environmental impacts, property impacts, cultural issues, vehicle operating costs, and so on. For such scenarios, road authorities will often revert to the use of multicriteria analyses (MCAs) or similar techniques. Where the benefits or disbenefits between solutions are not broadly the same, then comparison on a basis other than just cost will be required. MCAs enable such a comparison to be made, wherein the options are ranked across a range of user-defined factors. The challenge in applying MCAs is to determine the relative weighting between the different factors being assessed. Once the rating criteria have been set, each option is then scored across the criteria and the sum (often weighted) of the criteria is determined.DRR investments, in particular, infrastructure projects, may cause to decrease viability from a short-term perspective, but these pay off in a long-term perspective. While many developing countries have made some progress on formulating DRR policy framework, the implementation of DRR including road geohazard risk reduction still needs further progress. It is recommended that the governments of developing countries formulate planning guidelines on road geohazards risk management since risk management planning is used as the basis for funding for preparedness contributing to reduce the damage caused by catastrophic disasters. The guidelines would help the national and local governments of developing countries to institutionalize planning principles and practices, thus resulting in mainstreaming DRR in the transport sector.Design and Construction, Maintenance and Operation, and Contingency ProgrammingDesign and ConstructionEngineered (or structural) measures are engineering solutions to prevent or protect road damage due to geohazards. They include measures implemented as (1) preventive (proactive) measures implemented to lower the risk of geohazard failure; (2) emergency works, in highly susceptible areas or during geohazard events, that are subject to engineering design; and (3) recovery conducted as secondary damage protection or recovery works in a postdisaster stage that are subject to engineering design. Although the trigger to implement an engineered measure may vary, the fundamental approach is often similar, particularly when the solution to be implemented is a long-lived one, such as a concrete retaining wall. A well-engineered road with a functionally efficient geohazard-proof system will have more or less negligible vulnerability. The same road, if badly designed and constructed, may be 100% vulnerable. In other words, vulnerability depends on the level of exposure, susceptibility, and degree of preparedness.Structural measures include structures made of concrete or mortar, steel, wood, asphalt, geosynthetics, earth, and vegetation or bioengineering as well as their composites. Geosynthetics refers to any synthetic material, such as geotextiles (permeable material) and geomembranes (impermeable material). Earth structures include engineered slopes (cutting slope) and embankments used as a counterweight of a sliding slope toe. Engineered measures can increase the robustness of roads. They are usually implemented during the stages of road construction and operation and maintenance based on the priority of the countermeasures required on road hazard-prone locations. They are measures for geohazard risk management, but they can also be implemented as postdisaster recovery measures.The types of structural measures are selected depending on the type of geohazard on the road. Earthwork with surface drainage and vegetation (bioengineering) is always the basic countermeasure to consider for each type of geohazard. Depending on the method of construction and materials, it is necessary to account for economic efficiency, availability of construction materials and machines, social or environmental negative impacts, and the difficulty of maintenance. Structural measures comprise four types: (1) Structural measures for mountainside fall or collapse, (2) structural measures for valley-side collapse or river erosion, (3) structural measures for slide-type geohazards, and (4) structural measures for flow-type geohazards. Structural measures for a fall or collapse (slope stabilization) are shown as an example in Table 3.Table 3. Example of structural measures for mountain fall or collapseTable 3. Example of structural measures for mountain fall or collapsePrimary categorySecondary categoryTertiary categoryProcedure for concept design layoutSlope stabilization measuresCutting or removal of unstable rock and soilSlope cutting•Unstable rock or soil on the slope is identified through visual inspection.•Estimate the volume for cutting or removal of the mountainside slope.TrimmingScalingPrevention of erosion or slope surface instabilitiesSlope drainage•Lay out slope drainage and vegetation for soil slope.•For the spring portion or identified erosion, drainage shall be laid out to drain surface water.Vegetation or bioengineeringSlope reinforcementRock bolting•Area of unstable soil or rock on the slope is identified through visual inspection.•Estimate the volume of the slope reinforcement area.Pitching workSlope framework (grid beam)Buttress walls (cavity filling)Protection measures for endangered roadResistance or absorption against the shockRetaining and breast walls•Determine the possibility of hitting the road directly or by several bounces by simple distance from slope to toe experimentation.•Determine the possible maximum rockfall size and calculate the energy of hitting.•The protection measures are planned to be durable from the shock energy through energy absorption or by guiding the fall or collapse to the direction outside of the endangered road.Catch ditchesBarrier (catch fence, wall)Slope intermediate benchWire netting (rockfall net)Guide fall or collapse direction to the outside of the endangered roadGuide wallSheltersTunnelsTasks of design and construction are straightforward: investigate the cause of failure at the project site; estimate the likelihood and cost of future events; analyze mitigation options; and complete a detailed design and associated documentation. At the local office level, many countries including developing countries fully outsource the physical works to the private sector. The handbook offers standard templates for terms of reference (TOR) that can be adapted for procurements of design consultants and technical assistance projects with international development partners. The road authority staff can refer to details of the approaches and methodologies defined in the handbook.Maintenance and OperationIn contrast to structural measures, nonstructural measures for road geohazards, which enhance road geohazard risk management in the operations and maintenance stage, are any measures not involving physical construction. They are less expensive than structural measures and include: (1) Routine maintenance of previously constructed measures; (2) monitoring of geohazards (potentially using automatic measuring devices, linked to automated warning systems); and (3) road closures to prevent injury before (or during) a geohazard event.Nonstructural measures include risk avoidance methods, such as advanced warning, to prevent vehicle damage and loss of human life even if a geohazard event occurs. The early detection of anomalies is important to prevent disasters and avoid damage for road users. Road agencies have been successfully using automated geohazard monitoring, for example, monitoring of failing slope ground movement and geohazard triggers such as heavy rainfall or the rise of groundwater tables, as shown in Table 4. The monitoring is conducted at prioritized endangered road locations where structural measures have not been implemented owing to budgetary or technical difficulties. The monitoring results are used as criteria for early warning and precautionary traffic closures to avoid damage to road users.Table 4. Geohazard monitoring types and equipment usedTable 4. Geohazard monitoring types and equipment usedGeohazard phenomenaHardware supportSurface movementMonitoring CCTV camera, rockfall detector, extensometers, crack gauge, surface tilt meter, GPS devices, LiDARSubsurface movementBorehole inclinometers, pipe strain gauge metersGroundwater fluctuationGroundwater meter, piezometerRainfallRain gauge, automatic weather stationHow innovation and technology for geohazard monitoring can be effectively utilized to monitor risk roads in developing countries is the key to success. The monitoring results, such as displacement and distortion, are indispensable for the maintenance cycle to retrofit the risk roads. It is worth noting that monitoring mechanisms and measuring units of output data are different between monitoring devices in the global market. Technical standards must be developed in each country to adopt and diffuse road geohazards monitoring devices.Contingency ProgrammingContingency planning addresses contingency programming issues, such as postdisaster response and recovery, and the important issue of funding arrangements. As shown in Table 5, contingency programming consists of three distinct phases: (1) emergency preparedness before a geohazard event, (2) emergency response during and in the immediate aftermath of an event, and (3) recovery following the emergency to restore full functionality to the road network.Table 5. Contingency programming activityTable 5. Contingency programming activityPrograming phaseKey activityEmergency preparedness•Development of an emergency preparedness and response plan•Preparedness training•FundingEmergency response•Emergency inspection or postdisaster needs assessment•Emergency traffic regulation and public notice•Emergency worksRecovery•Management of the recovery•Repair•Rehabilitation and reconstructionPutting emergency preparedness, emergency response, and recovery into practice is a great challenge for national and local road authorities of developing countries. Many developing countries lack the institutional, technical, and financial capacity to effectively cope with disasters. National road authorities must formulate the mechanisms for the implementation of contingency programming, which would preferably be expressed as operation guidelines. These mechanisms comprise institutional, technical coordination, and funding mechanisms. For example, the national road authority should support local road authorities by coordinating the organizations concerned (meteorological agency, police, rescue agency, and so on) and deploying specialized teams to respond to catastrophic disasters. What is most important is how contingency funds are allocated when geohazard events occur because such emergency events would require funding beyond that of the road authority’s day-to-day activities.Case StudyThe case studies in Brazil and Serbia were conducted to verify the applicability of the framework to developing countries. Key elements for developing a road geohazard risk management framework were identified so that the framework is applicable to any country contexts. Documents and information about road geohazard risk management practices were reviewed to cover all technical areas defined by the proposed framework. The case studies identified gaps that can be improved:Brazil Case StudyThe study summarizes the institutional capacities of geohazard risk management at the different government levels in Brazil, focusing particularly on the federal government and state government. The study selected the São Paulo state as a case study for two reasons: (1) it is a state vulnerable to landslide disasters; and (2) the World Bank is implementing an investment operation in the road sector, including disaster risk management. There is no comprehensive approach to road geohazard risk management in order to protect the road infrastructure from geohazard events. Such an approach should be coordinated and implemented by relevant stakeholders. However, road administrators and other relevant institutions often work individually, and any official coordination mechanism on geohazard risk does not exist. An integrated, multiinstitutional approach is essential to enhance geohazard risk management of road infrastructure.The case study’s findings and recommendations for the enhancement of road geohazard risk management in Brazil include, but are not limited to: •Ad hoc methodology for geohazard risk assessment. Road administrators are identifying and assessing road geohazard risks substantially depending on the experiences of local engineers, normally through visual inspection of roads. Though the experiences in local situations help to identify problems, this approach has certain limitations, not being based on any geological or statistical assessments;•No cost-benefit assessment for geohazard mitigation measures. Although geohazard mitigation could bring a substantial economic benefit by preventing a chronic need for recuperation of roads after disasters, economic assessment of geohazard mitigation measures from the life-cycle viewpoint has rarely been conducted;•Little data sharing among stakeholders in geohazard management. Environmental and geohazard risk-related information is not yet integrated with the transport sector. Each branch has been considered separately over the years without looking at each other’s data or information. For successful road geohazard risk management, data are one of the most valuable assets, and as such, it becomes fundamental that every institution involved in the area is aware and knowledgeable about all the available data; and•No strategic contingency program. Although a certain protocol exists at the local unit level of road agencies for preparing for geohazard events, no official and written procedures or contingency plan has been developed, which is key to reduce potential losses of life or assets under a natural disaster threat.Serbia Case StudyIt was found that road geohazard risk management is still new terminology, for which there is not yet a specific law or clause in Serbia. The case study’s findings and recommendations include, but are not limited to: •There are no separate technical standards, guidelines, or operational manuals for road geohazard management;•No data are available on cost-benefit analysis for road geohazard risk reduction in Serbia because the responsible authority repairs the damaged section of the road whatever the cost may be, considering the importance of the road; and•Although geohazard risk management planning for new roads is performed to minimize the total life-cycle cost of the new infrastructure, there were no geohazard risk reduction plans for existing state roads within operational maintenance programs.After the 2014 floods caused damage estimated at 5% of the Serbian gross domestic product (GDP), the National Disaster Risk Management Program for Serbia was officially launched in 2015. The program has created a common platform for managing risks associated with various types of disasters by identifying potential hazard risks and reducing them in the long term. It emphasizes a dual view of risk management on transport, not only as an exposed infrastructure but also as a key part of preparedness, response, rescue, and reconstruction. The program also provides an open platform to enable various sectoral actors and donors to coordinate and avoid replication of similar activities.ConclusionThis study developed an institutional and technical framework for road geohazard risk management in developing countries through the review of best practices for disaster prevention measures in the world. The adopted management approach aligns with the risk management practices in the ISO 31000. Since developing countries lack sufficient funds and knowledge to implement full-scale disaster prevention measures, it was required to convey necessary institutional and technical know-how in an understandable manner for policy makers and practitioners in national and local governments. This road geohazard risk management framework covers: (1) institutional setup, (2) road geohazard risk management for new roads, and (3) road geohazard risk management for existing roads. Those three activities are institutionalized in the governments and road agencies as road assets are financed by the government budget in most cases. The road geohazard management activities fit within the infrastructure asset management practices, such as the AASHTO’s Transportation Asset Management.The proposed framework is comprised of the stages of (1) institutional capacity and coordination, (2) systems planning, (3) engineering and design, (4) operations and maintenance, and (5) contingency planning. The framework would be put in place in a step-by-step manner depending on the capacity and financial constraints of the project-implementing countries. It also enables those countries to select simple/low-cost technology or high-cost technology case by case. The applicability of the framework was verified by conducting the case studies to collect information about disaster risk management practices in Brazil and Serbia and by consulting with The World Bank Task Team Leaders and experts in the field of transport and disaster risk management. For future work, a disaster risk management framework needs to be developed in other fields in civil engineering and against other natural disasters in order to mainstream DRR in developing countries.Data Availability StatementAll data that support the findings of this study are available from the corresponding author upon reasonable request.AcknowledgmentsThis study represents part of the results of the “Road Geohazard Risk Management Handbook.” World Bank, Washington DC. This is an adaptation of an original work by The World Bank. Views and opinions expressed in the adaptation are the sole responsibility of the author or authors of the adaptation and are not endorsed by the World Bank.References Kikuchi, R., M. Numada, and K. Meguro. 2015. Fundamental research on the evaluation of disaster prevention-related international support business that focuses on the future of damage mitigation effect: Focusing on the number of deaths relieving effect, 317–320. Tokyo: Institute of Industrial Science, Univ. of Tokyo. Park, J., T. P. Seager, P. S. C. Rao, M. Convertino, and I. Linkov. 2013. “Integrating risk and resilience approaches to catastrophe management in engineering systems: Risk analysis.” Risk Anal. 33 (3): 356–367. Solheim, A., et al. 2005. “International Centre for Geohazards (ICG): Assessment, prevention, and mitigation of geohazards.” Norw. J. Geol. 85 (1): 45–62. World Road Association. 2013. Risk associated with natural disasters, climate change, man-made disasters and security threats. Paris: World Road Association.

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