Below is the uncorrected machine-read text of this chapter, intended to provide our own search engines and external engines with highly rich, chapter-representative searchable text of each book. Because it is UNCORRECTED material, please consider the following text as a useful but insufficient proxy for the authoritative book pages.
71  Understand the Hazards and Threats (Step 5) This step considers the level at which and the procedures used by your agency to identify the potentially disruptive hazards or threats facing your transportation system. Many transportation agencies have achieved some level of understanding of the top hazards and threats to their system, even if it is simply based on institutional knowledge or drawing upon hazard mitigation processes driven by the stateâs emer- gency management department. Understanding potential hazards and threats translates to having a comprehensive picture of those that constitute the greatest concern across the system. This is particularly important as the preferred strategies for mitigating the hazards and threats may, in fact, change when the analysis is expanded to include the collection of affected assets. For example, one strategy might be appropriate for a given hazard or asset, but another might be more cost-effective in reducing the impacts across a few hazards or reducing the hazard across several assets. The first step in this process is to identify comprehensively which assets in the transportation system may be exposed. This chapter focuses on two important pathways to assess agency resilience readiness and maturity: ⢠The depth and breadth of the technical work (for example, the tools and resources used, availability of data, etc.), and ⢠The maturity of the agency to conduct the technical work and integrate the results into its practices. A fully mature agency will have conducted a sophisticated, well-vetted, all-hazards exposure analysis that considers the interdependencies across other sectors. The recommendations from these analyses will have been institutionalized within the agency. This information is a critical part of the systems-level vulnerability or risk analysis (comprising Steps 5 to 7 of the Framework), the prioritization of detailed asset-level assessments (Step 8C), and investment decisions (Step 9). Capability Factors and Levels of Maturity The maturity levels are presented in the descriptions below for each factor and then summarized in the self-assessment table. C H A P T E R  7
72 Mainstreaming System Resilience Concepts into Transportation Agencies: A Guide Factor 5.1: Have you established a working group for a system-wide assessment? To ensure that the analyses draw on and are driven by the most up-to-date information, practices, resources, and tools, it is important to include subject matter and agency experts in the self-assessment process. Note that Step 2: Organize for Success includes a factor focusing on whether an institutional mechanism has been created to lead your agencyâs resilience strategy. In contrast, this factor focuses on the existence of a working group to guide the system-wide assessment of hazards and threats. Given the interdependencies between transportation and other sectors, informed transporta- tion decisions will also often require discussions with other agencies. In addition, collaboration with the private sector can provide an important source of data, such as from providers of traffic and navigation apps that collect hazard impacts in real time (e.g., data that can be used to iden- tify incidence hot spots for poor visibility during a dust storm event). Establishing a working group provides a forum for sharing data, resources, and knowledge that collectively are indis- pensable for understanding hazards and threats. Further, a working group can be an important source of information and agency guidance for the self-assessment steps that follow. The levels of maturity in this factor are distinguished by the degree to which your agency has formed and utilized a working group to guide the system-wide assessment. ⢠Level 1: We have identified agency participants and formed an ad hoc working group to guide the hazards and threats analysis scope and milestones. Our working group is largely composed of internal unit representatives. ⢠Level 2: We have formed a formal working group to guide the hazards and threats analysis scope and milestones. The working group has identified key technical capabilities to support this self-assessment and enlisted representatives from other agencies to participate in the working group. The working group has (or will) prioritize the recommendations from the analysis. ⢠Level 3: We have achieved Maturity Level 2. In addition, the working group has formed subcommittees as needed to draw on external technical experts to support the technical assessment, including experts on climate science, environmental impacts, and cybersecurity specialists. The working group has also identified roles and responsibilities for implementing the findings, including establishing an ongoing institutional responsibility for the working group. Factor 5.2: Have you identified natural hazards that may impact your transportation system? Table 13 shows examples of natural hazards that may impact transportation. An event might include multiple hazards such as a tropical storm with heavy winds, precipitation, and coastal flooding. Although Table 13 covers most of the primary natural hazards in the United States, your agency may need to consider additional hazards. For larger regions, hazards will likely vary by geography. Importantly, natural hazards often result in physical damage to an asset or lead to disruptions in system operations. It is important to identify hazard exposure that could lead to both types of impacts. The process of identifying hazards can include: (1) internal agency workshops and discussions; (2) review of available resources and reports, which can include traffic incident reports, after- action reports, and emergency reimbursement forms; (3) review of maintenance records; and (4) interviews with key agency staff to discuss past experiences. It is also important to identify how natural hazards may change over time. For some natural hazards, climate change may already be influencing the stressor, such as increased incidents of extremely hot days. This presents a disconnect between todayâs conditions and the design values and environmental
Understand the Hazards and Threats (Step 5) 73  conditions that were considered during the design and construction of existing assets. Moving forward, future changes in climate may impact the robustness of todayâs designs as well as the integrity of existing assets. Because of this, it is important that climate-related hazards are projected for change over the coming century. This also translates to other hazards where external drivers may affect the frequency and/or magnitude of the event (e.g., land cover change in a watershed can affect riverine flooding potential). There are numerous data resources for this effort. For example, NOAAâs Storm Events Data- base can be used to assess whether tornadoes have occurred within your region (NOAA n.d.). It is also important to identify any hazard data that has been vetted and peer-reviewed for use in your region. By using accepted data, you will provide consistent messaging to the public with usable outcomes that are easily transferable to other agencies also conducting assessments. However, if the data is inadequate, outdated, or not appropriate for your analyses, then the reasoning for not using this data should be documented with a discussion of how the findings may differ based on data choice. ⢠Level 1: We have reviewed hazard mitigation plans and reached out to our agencyâs main- tenance staff for their knowledge of past âhot spotsâ of exposure. We have also reviewed guidance documents on asset sensitivity to hazards such as those available on FHWAâs website (U.S. DOTâs Sensitivity Matrix). ⢠Level 2: We have achieved Maturity Level 1. In addition, we have reviewed after-action reports and analyzed maintenance response records to identify past events that resulted in disrup- tions to the transportation system. ⢠Level 3: We have achieved Maturity Level 2. In addition, we have analyzed future climate changes that might affect the transportation system. This includes reviewing national, state, and local hazard reports and reaching out to specialists (e.g., climate scientists) and other experts on individual stressors. Factor 5.3: Have you identified physical or human-caused threats that may impact your agency? Examining disruption threats against a transportation system and/or your agency also includes those that might originate from human causes, either intentional or not (see Table 13). Natural Hazards Human-Related Threats Winds Precipitation Winter Storms Ice storms Blizzards Coastal Environment Sea-level rise causing tidal flooding and inundation Storm surge Tsunami Coastal cliff retreat Coastal erosion Other Hazards Wildfires Droughts Cyberattacks Severe winds Tornadoes Dust storms Temperature Fluvial flooding (including dam failures, riverine flooding, flash flooding) Pluvial flooding (such as from extreme rainfall, snowmelt) Public health emergencies Terrorism Pandemics Unintentional/accidental harm Extreme temperatures Warming average annual and/or seasonal temperatures Freeze-thaw days Geohazards Volcanic eruptions Earthquakes and seismic activity Subsidence/sinkholes Landslides and mudslides Rockfalls Permafrost thaw Table 13. Examples of natural hazards and threats that may impact a transportation system.
74 Mainstreaming System Resilience Concepts into Transportation Agencies: A Guide Terrorist attacks against transportation systems worldwide have caused significant disruptions to system operations as well as fatalities and injuries often resulting in significant economic impacts. Although not as prevalent in the United States as in other countries, domestic terrorists have targeted U.S. transportation systems as well, especially public transit services. Physical attacks against command and control facilities could cause a loss of system management abilities that result in operational disruptions (e.g., a 2014 arson attack against the Federal Aviation Administration regional operations center in Aurora, Illinois, closed Chicago airspace and caused the rerouting of air travel for 3 weeks). In addition to possible human-caused physical attacks against your agency, transportation officials should also consider the possible disruptive effects of public health emergencies that could affect system operations and/or employee availability. An example of this is the 2020 COVID-19 virus pandemic (coronavirus) that significantly affected international and domestic travel. In its worst manifestation, pandemics could cause the physical quarantine of entire communities that would require blocking and monitoring of roads and transit access. Also, many of the national, state, and local pandemic transportation-related plans examine the challenges of transportation agencies providing services during pandemic/epidemic outbreaks when many of their staff are sick or taking care of family members. Although transportation agencies have an important role to play in identifying potential physical threats and strategies to protect against them, the lead role in such efforts is usually held by law enforcement agencies. Therefore, effective efforts for this factor include participation in multi-agency planning and field exercises. The distinctions in the maturity levels for this factor reflect the degree to which your agency has examined all possible physical threats to the transportation system and the level to which your agency interacts with the agencies charged with security and protection of critical infrastructure. ⢠Level 1: We are aware of the types of physical threats that confront the agency and its employees, including concerns about crime, terrorism, assault, and those relating to CBRNE (chemical, biological, radiological, nuclear, and explosives). This awareness lies primarily in the operations unit in our agency. We maintain a security awareness program. ⢠Level 2: We have achieved Maturity Level 1. In addition, we have consulted with outside professionals in law enforcement, the Department of Homeland Security (DHS), Transpor- tation Security Administration (TSA), the transportation security industry, and public health agencies to identify specific threats to our agencyâs assets and operations. ⢠Level 3: We have achieved Maturity Level 2. In addition, we participate in a working group(s)/ coordinating committee(s) consisting of security, enforcement, transportation, public health, and other sector representatives whose focus is on protecting critical infrastructure and mission-critical operations. We actively participate in the development and updates of the State Hazard Mitigation Plan. We also participate in field exercises and drills that simulate physical attacks against transportation infrastructure. Factor 5.4: Have you identified cyber threats to your agency? As transportation agencies and their command and control systems become ever more dependent on digital and internet-based communications, they become more vulnerable to cyberattacks. The February and March 2018 cyberattack against the Colorado DOT (CDOT) is an example of the type of threat such attacks represent to transportation agencies. At its worst, over half of CDOTâs computers were affected by ransomware malware affecting almost every unit in the agency. Traffic operations computer networks had been separated from CDOTâs business network by a next-generation firewall that detected and blocked the ransomware from entering its network. Thus, traffic command and control centers were not attacked. The agency
Understand the Hazards and Threats (Step 5) 75Â Â The Basics of Modeling Coastal Flooding (National Climate Assessment n.d.) Coastal flooding is directly affected by relative sea level (i.e., local conditions), which is calculated as the combination of global mean sea level rise, regional conditions, and local conditions. Global mean sea level rise is largely due to the thermal expansion of warming seawater and meltwater from glaciers and ice sheets. Regional conditions that affect changes in relative sea level primarily include changes in regional ocean currents, while local conditions may include ground settling, upstream flood control, erosion, and uplift/subsidence. Rising sea level can translate to higher high tides and an increase in high-tide flooding. The Federal Interagency Sea Level Rise and Coastal Flood Hazard Scenarios and Tools Task Force, a joint task force of the National Ocean Council and the U.S. Global Change Research Program, developed scenarios of global mean sea level and provided regionalized global scenarios for the United States coastline. The six global mean sea level rise scenarios developed are shown in the figure below. There is higher probability that the lower sea level rise scenarios will occur over the coming century [e.g., under the RCP4.5 (representative concentration pathway 4.5), the lowest scenario of 0.3 meters by 2100 has a 94% chance of occurring, while the intermediate-low of 0.5 meters by 2100 has a 73% chance of occurring]. The U.S. Army Corps of Engineers Sea Level Rise Calculator and NOAA Sea Level Rise Viewer are public tools that translate the global mean sea level rise to local conditions. Models are routinely used to simulate coastal flooding during storm events, such as a hurricane or norâeaster, under current and future sea levels. The winds of a coastal storm can produce a surge of water that moves toward the coastline. The height and inland extent of the surge depends on numerous factors, such as storm intensity, forward speed, size, angle of approach, central pressure of the storm, and coastal features. In transportation assessments, generally one of two surge models is used: (1) Sea, Lake, and Overland Surges from Hurricanes (SLOSH), a two-dimensional hydrodynamic circulation model that simulates storm surge for hurricane forecasts (NOAA uses SLOSH operationally, hence it is computationally efficient and can be run under a variety of storm simulations such as storm track, intensity, speed, and size) and (2) ADvanced CIRCulation (ADCIRC), a more sophisticated, very high-resolution finite element model that combines rain, pressure, and wind fields to predict storm surge and flooding. In addition to the surge, some assessments may further capture wave actions as simulated by Simulating WAves Nearshore (SWAN), a high-resolution regional wave model.
76 Mainstreaming System Resilience Concepts into Transportation Agencies: A Guide adopted a four-phase strategy in response: containment, eradication, recovery, and sustainment (U.S. DOT 2019). This factor reflects the extent to which your agency has systematically and routinely examined your internet and digital network resources to identify potential threats. The distinction among maturity levels reflects the degree to which this assessment has been comprehensive and the level to which you have taken a future-oriented perspective on the likely characteristics of such threats. Note that factors similar to this one are also found in other steps in the self- assessment tool. ⢠Level 1: We have reviewed resident information technology (IT) systems and the potential targeting against these systems. The history of attacks against each system has been documented. ⢠Level 2: We have achieved Maturity Level 1. In addition, we have consulted with outside professionals in government and industry to identify all information system weaknesses and points of failure. ⢠Level 3: We have achieved Maturity Level 2. In addition, we have considered how cyber threats may evolve in the future. This includes maintaining constant vigilance through daily assessments of the âInternet of Thingsâ (IoT) and the cyber universe. We have engaged âwhite-hatâ hackers to attack our IT systems to determine weaknesses. Factor 5.5: Have you identified relevant hazard metrics by asset type? For asset exposure analyses, it is important to identify relevant hazard metrics to determine whether current and future environmental conditions exceed the design parameters associated with each asset type (see text box FHWA Recommended Asset Types) (FHWA 2017). Design standards and discussions with engineers are generally an appropriate path for identifying relevant hazard metrics. For example, a state design manual may require a culvert to be built to withstand a stream flow rate at the 10% annual exceedance probability (also known as the 10-year return period). The value of this rate is generally provided in the design manual devel- oped using a baseline set of observations over a given time period. However, these values will change in response to such factors as changing environmental conditions and land use and may fluctuate depending on what years are used to represent the observational record. This is particularly important in regions where there has been a statistically significant change in values over the historic record. At most agencies, designed standards have been updated and enhanced to higher standards over time. This translates to older assets having been built with outdated parameters given todayâs standards. This factor catalogs appropriate hazard metrics by asset type and may also include corresponding time periods that align with any variations in design standard values. A more comprehensive understanding of hazard metrics also includes expanding your effort to review past engineering studies that identify asset failures and empirical research. The distinctions in maturity levels reflect the extent to which your agency has reviewed design manuals and standards for different asset types in light of expected threats and the level to which past failures have been examined and lessons learned incorporated into your agencyâs standard operating procedures and guidelines. ⢠Level 1: We have reviewed design manuals to infer critical thresholds applicable to each asset type. We have used these resources to identify the hazard metrics and thresholds that, if exceeded, could damage our assets. ⢠Level 2: We have achieved Maturity Level 1. We have also interviewed our engineers to gain additional understanding and knowledge regarding design and failure thresholds. We have FHWA Recommended Asset Types ⢠Roadway pavement ⢠Bridges ⢠Culverts ⢠Signage ⢠Guard rails ⢠Intelligent Transportation System (ITS) components ⢠Lights ⢠Weigh stations ⢠Rest areas
Understand the Hazards and Threats (Step 5) 77  The Basics of Climate Projections (IPCC 2014) Global climate models (GCMs) are mathematical models that characterize the Earth system processes (atmosphere, ocean, cryosphere, and land surface) to simulate past and future climate. GCMs are developed and run at research institutions around the world, where each climate model uses a distinct set of algorithms to simulate large-scale to small-scale processes. GCMs can be run to simulate several scenarios that represent changes in radiative forcing over time linked to plausible changes in land use, population, fossil fuel use, etc., that correspond to different greenhouse gas concentrations in the Earthâs atmosphere. These scenarios have been developed by the international climate community and are used to drive climate models. The climate impact community currently focuses on four representative concentration pathways (RCPs) in considering how future society may evolve, considering equivalent carbon dioxide concentrations: ⢠RCP2.5: Concentrations peak in the early part of this century and then decline substantially. This is not considered plausible as an aggressive reduction in emissions would need to have occurred already. ⢠RCP4.5: Continued increase in concentrations until 2040 and then a decline with stabilization achieved by end of century. ⢠RCP6.0: Continued increase in concentrations until 2080 and then a decline after. ⢠RCP8.5: Aligns with our current trajectory but suggests significant increases in concentrations by end of century. For climate impact assessments, results across multiple climate models are generally used to provide an indication of the scientific uncertainty when modeling the climate system. Results tied to multiple concentration scenarios provide an indication of how change in future society may influence future climate projections. Depending on the purpose of the impact assessment, multiple time periods may be used to assess how future change may evolve over the coming century. This is a requirement for an asset with a long design life that needs to be resilient against todayâs and future conditions. (continued on next page) This figure shows the equivalent carbon dioxide (CO2) concentrations in the atmosphere under a series of future scenarios (IPCC 2014)
78 Mainstreaming System Resilience Concepts into Transportation Agencies: A Guide The Basics of Climate Projections (IPCC 2014) (Continued) Peer-reviewed climate projections are publicly available that assess future change for locations in the United States. The following climate datasets are often used in many transportation vulnerability and risk assessments: ⢠Localized Constructed Analogs (LOCA): Publicly available, statistically down- scaled GCM data was developed by the Scripps Institute of Oceanography at the University of California, San Diego, covering the continental United States. Downscaled results are provided at 1/16 degree spatial resolution for daily temperature and precipitation for RCP4.5 and RCP8.5 for more than 30 climate models from the World Climate Research Program (WCRP) Coupled Model Intercomparison Project (CMIP5) from 1950 to 2099. FHWA provides a CMIP processing tool that a user can run on their desktop after downloading LOCA data, to produce several temperature and precipitation projections relevant to transportation practitioners. The second version of this tool that uses LOCA data has not yet been published on the FHWA website at the time of publication but is expected to be released soon. ⢠Coordinated Regional Climate Downscaling Experiment (CORDEX): Publicly available, regional, downscaled GCM data is available through the North American Coordinated Regional Climate Downscaling Experiment (NA-CORDEX) covering the continental United States, a portion of Alaska, and the Caribbean. For this effort, regional downscaling refers to a GCM that is used to drive a regional climate model (RCM). There is a growing number of GCM/RCM combinations for RCP4.5 and RCP8.5. The spatial resolution is at 0.22 or 0.44 degrees. Because this effort draws on regional modeling, there are several climate variables, including temperature and precipitation, available at varying temporal scales from 1950 to 2100. There are also processed climate projection data available through federal, state, and academic portals. These provide helpful information and data. However, note that these portals are unlikely to provide tailored projections that represent specific thresholds and hazard metrics of interest when assessing impacts on your transportation system. investigated how asset types were impacted during past events, including examining after- action reports. ⢠Level 3: We have achieved Maturity Level 2. In addition, we have reviewed empirical research, engineering studies on asset failures as well as other technical references. This information has been incorporated into our metrics and standard design procedures. Factor 5.6: Have you collected geographic information system (GIS)-based transportation asset data necessary to perform an exposure analysis? Transportation asset classes should be identified in as comprehensive a manner as possible. For example, the asset classes for a state DOT might include pavements, bridges, culverts, signage, guard rails, intelligent transportation system (ITS) technologies, and streetlights.
Understand the Hazards and Threats (Step 5) 79  To be useful for a system-wide assessment of hazards and threats, the database should include asset location, condition, and use (see text box FHWA Recommended Asset Data for Vulnerability Assessments). Data on costs and consequences (such as replacement cost, level of use, evacuation routes) are addressed in Chapter 8, Step 6. In addition, information should be collected that is relevant to assess susceptibility factors that may amplify the damage caused by a hazard or threat. The distinction in maturity levels for this factor reflects the extent that your agency has developed a database for the assets for which it is responsible. ⢠Level 1: We have developed an asset data inventory for pavement and bridges that includes location, condition, and use. Assumptions have been made to fill in gaps as needed. We have developed written documentation describing how the data were collected and incorpo- rated into our GIS systems. ⢠Level 2: We have achieved Maturity Level 1. In addition, our GIS database includes location data and characteristics on the next most important asset types (such as culverts or other drainage treatments). The data are considered complete and are updated on a set schedule. The data attributes have also been screened to support linking hazards to the asset thresholds. All datasets are accurately georeferenced to elevation data and other relevant data sources. For example, roadway travel lanes are not depicted by a single georeferenced line for highways but with two lines to capture travel lanes. ⢠Level 3: We have achieved Maturity Level 2. In addition, our GIS database includes auxiliary assets (e.g., signage, guard rails, ITS, lights, weigh stations, rest areas, geotechnical hazard mitigation measures, etc.). These assets may also include protective measures such as geo- technical assets including retainer walls, safety netting, guard pillars, and so on (where guard pillars protect against vehicular terrorism and slope instability). The data are updated at least every 2 years. Factor 5.7: Have you evaluated the current and future spatial extents of the natural hazards facing your agency? Natural hazards may range from chronic risks (that is, occurring regularly over a long period), occur multiple times a year but not reoccurring every year, to rarely occurring. The description of the hazard or threat provides the magnitude and duration of the event. Hence, there may be a series of hazard exposures assessed for a given hazard. For example, under coastal flooding, there may be a series of coastal flood exposures that are important to assess. Different frequencies of occurrence, magnitudes, and extents of exposure will likely be associated with different hazards. This factor develops a set of hazard data across the geo- graphic area of interest. It can be challenging to accurately portray the likelihood of a hazard occurring based on historical data given the value can change depending on the years examined. This is particularly true for assessing the likelihood of extreme events that rarely occur. To ensure credible values, it is important to conduct sensitivity tests to reveal any outliers that may skew the data or conduct a Mann-Kendall Test to quantify if conditions have significantly changed. (The Mann-Kendall Trend Test is used to analyze data collected over time for consis- tently increasing or decreasing trends.) In some instances, changing conditions, such as climate change or the increasing sophistication of hackers, will already be notable when comparing recent events to events experienced several years in the past. FHWA Recommended Asset Data for Vulnerability Assessments (FHWA 2017) ⢠Age of asset ⢠Design life ⢠Stage of design life ⢠Geographic location ⢠Current and historical performance and condition ⢠Elevation information ⢠Structural designs ⢠Occurrence/location of maintenance events ⢠Structural design (as-built plans)
80 Mainstreaming System Resilience Concepts into Transportation Agencies: A Guide The future likelihood of whether a hazard might occur introduces a level of uncertainty in the estimation. [Generally, likelihood is considered as the probability of the event occurring in a given year ranging from 0% (full confidence that the event will not happen) to 100% (full confidence that the event will happen)]. A few methods are possible to consider future change, such as trend analysis and processing data from causal models. Trend analysis. This method uses the observed change in the frequency or magnitude of specific hazards and threats that have occurred over a past time period and linearly extrapolates the trend into the future. This can be appropriate for hazards that have shown some evolution in frequency or magnitude but are not intricately linked to nonlinear drivers (e.g., climate change). Future trends projected from causal models. For most natural hazards (but not for such hazards as seismic events), a changing climate will influence the likelihood of future events occurring over the coming century. For future conditions, it is often important to assess the likelihood of an event occurring for plausible future scenarios relating to those factors contributing to the hazard. For example, in climate change projections, a plausible future scenario assumes global society will evolve along a given trajectory in energy use, technological advances, population growth, etc. Assuming a future scenario occurs and given the credibility of the underlying causal relationships in the model, estimates of the likelihood of future events occurring can be made (see the example of the probability of coast flooding below). This can then be done across a few different trajectories to provide a range of possible futures (see textbox The Basics of Climate Projections). For hazards that can be characterized by spatial exposure, such as flooding and earthquakes, the minimum analysis for identifying potentially affected assets is to develop GIS hazard maps that portray future impacts under likely and the most extreme futures. If an asset is not affected at the most extreme level, then it is intuitively understood that the asset is not likely to be affected by less extreme future conditions. This is a conservative measure to ensure no potentially affected asset is dropped from future analyses. For a more sophisticated approach, hazard stressors can be estimated for multiple future scenarios and presented visually in a way that captures the uncertainty in future projections. For example, likely damaged areas from varying Richter scale earthquakes can indicate how extensive the damage might be. Climate-change-related analyses are different than those for other hazards in that much research and guidance has been developed on how future projections should be made. There are different approaches in developing future climate scenarios for assessing which transportation assets are at risk. There may be a preference to (1) identify climate simu- lations that represent specific future physical conditions (e.g., GCM/RCP combinations that suggest hot and dry summer conditions, referred to by some methods as âclimate narrativesâ or âstorylinesâ); (2) identify climate simulations that represent plausible futures at the median and extreme values of the stressor; and (3) average across the ensemble of GCMs for the median and uncertainty ranges for each stressor. With higher levels of agency maturity, your agency will become increasingly savvy as to which approach is most appropriate for analyses. For example, if the analyses use hazard stressors independently, then it may be appropriate to work with the median/extremes for each stressor. If the analyses use hazard stressors collectively, then it may be more acceptable to work with stressor values from estimates of future physical conditions. Given there are several GCMs available, some researchers feel more confident using the ensemble averaging approach. However, it is important to recognize that averaging across climate model results for some climate stressors may lead to nonsensical results (e.g., climate models could suggest significant increases in a precipitation stressor as well as significant decreases; the average, though, suggests minimal change). Because of this, care should be used when evaluating the results to ensure confidence in using the ensemble average.
Understand the Hazards and Threats (Step 5) 81  Example of Probability of Coastal Flooding in 2030 Under a Future Sea Level Rise Scenario, Boston (MassDOT-FHWA 2015) Coastal flooding was defined at a depth greater than or equal to 2 inches (5 cm). The probability of exceeding this threshold is presented by color shading in geographic locations of the study area based on ADCIRC-SWAN modeling. Along with these types of methods, it is important to identify and account for susceptibility factors that may amplify impacts. Susceptibility factors may then include the timing of the event occurring (e.g., Is it more apt to happen at the close of the rainy season when soils are saturated or is it more apt to occur after significant drought conditions?), other environmental conditions that parallel the event (e.g., snowmelt in spring), and societal/environmental changes (e.g., more impervious surfaces increasing runoff ). The distinctions among the maturity levels reflect the degree to which you have examined the spatial extent of current and future natural hazards. ⢠Level 1: We have collected/developed GIS data showing the areas currently susceptible to all identified hazards. We have used available tools to project how hazards may change over the life span of our assets. This entails using past conditions to assess the likelihood of the hazards and threats occurring. For example, assume a precipitation event that has a 1% chance of occurring in any given year is projected to occur with significantly more frequency in the future or the likelihood of a winter storm occurring in a given year. For climate change, projections are based on the worst-case emissions scenario using the ensemble average of GCMs.
82 Mainstreaming System Resilience Concepts into Transportation Agencies: A Guide ⢠Level 2: We have collected/developed GIS data showing the areas currently susceptible to all identified hazards. We have used available tools to project how hazards may change over the life span of our assets. For climate change, projections are based on multiple scenarios to capture emissions uncertainty and provide median and extreme climate model projections to capture model uncertainty. When possible, we have estimated the probability of the hazards occurring. ⢠Level 3: We have achieved Maturity Level 2. In addition, we have applied models to map those hazards that are not directly provided by models (e.g., the use of climate models for drought, surge, landslides, wildfires, etc.). When possible, we have estimated the probability of the modeled projections. We considered the interaction amongst hazards when esti- mating potential impacts (e.g., How likely is it that two hazards occurring sequentially or in tandem will exacerbate resulting impacts?) and used this information to identify which (if any) combinations of hazards and threats pose a significant concern. We have also con- sidered human influences on the environment (e.g., levees and dams, changes in impervious surfaces, etc.) that can amplify/dampen the hazards. Factor 5.8: Have you identified transportation assets exposed to natural hazards? The previous factor focused on your agencyâs efforts to identify the extent of hazard exposure in your study area. It is next critical to identify which transportation assets might be exposed to hazards and threats. This exposure could result in damaged assets and/or system operational disruptions. This factor involves overlaying the hazard data with the asset information dis- cussed in prior factors. Such overlays can be readily accomplished through GIS applications. The distinction among maturity levels is the level of comprehensiveness of the analysis in identifying exposed assets. If possible, itâs also important to identify the associated uncertainty and confidence (see textbox Confidence and Uncertainty in the Exposure Analysis). ⢠Level 1: We have identified assets that exceed specified thresholds of the observed/projected hazards and threats. This information is captured in a GIS database. For those hazards where future thresholds might be reached (e.g., when precipitation levels might create flood- critical flows), we have included the estimated length of time before such thresholds are likely reached (e.g., within the next decade, by mid-century, etc.). This is done by overlaying the time of exceedance with the design life of the asset. ⢠Level 2: We have achieved Level 1 maturity. In addition, we have included in the GIS database the degree to which the hazards exceed the critical thresholds. We have further indicated the levels of certainty and confidence of exposure. Our database also includes information on the past occurrence of hazards and threats over at least the past 20 years. We have developed metadata for all of this data in the GIS database. ⢠Level 3: We have achieved Maturity Level 2. In addition, we have evaluated exposure from a systems perspective (not just asset-by-asset) across the transportation network. Factor 5.9: Have you developed written documentation that describes the data, methodologies, and findings of the exposure analysis? To ensure that the tools, resources, data, decisions, and institutional knowledge applied in this step are captured, it is important to document the process along with the findings. It is also important to have written documentation on the methods and approaches used for this type of analysis given that the state-of-the-art and state-of-science are ever-evolving. A writ- ten document will also help to establish a baseline when methods and approaches are updated.
Understand the Hazards and Threats (Step 5) 83  The distinction among the levels of maturity is defined by the thoroughness, level of review, and availability of the documentation. ⢠Level 1: We have written documentation of the data used, our methodologies, and findings in the form of technical memoranda. ⢠Level 2: There is a single document that comprehensively describes all aspects of the expo- sure assessment. The working group has reviewed the document. ⢠Level 3: We have achieved Maturity Level 2. In addition, we have produced a publicly available document that is graphically rich and aimed at a broader nontechnical audience. Table 14 shows the factors that are included in the self-assessment tool. The maturity levels for each factor are presented in the descriptions of each factor. Confidence and Uncertainty in the Exposure Analysis (IPCC 2014) When considering future projections, the Intergovernmental Panel on Climate Changeâs Fifth Assessment Report suggests the following two metrics to communicate the degree of certainty in findings (note that these terms are transferable to historic analyses as well): ⢠Confidence: âRelated to the validity of a finding, based on the type, amount, quality, and consistency of evidence (e.g., mechanistic understanding, theory, data, models, expert judgment) and the degree of agreement. In this report [Fifth Assessment Report], confidence is expressed qualitatively.â ⢠Uncertainty: âThe degree of certainty in each key finding of the assessment is based on the type, amount, quality, and consistency of evidence (e.g., data, mechanistic understanding, theory, models, expert judgment) and the degree of agreement. The summary terms to describe evidence are: limited, medium, or robust; and agreement: low, medium, or high. The likelihood, or probability, of some well-defined outcome having occurred or occurring in the future can be described quantitatively through the following terms: virtually certain, 99â100% probability; extremely likely, 95â100%; very likely, 90â100%; likely, 66â100%; more likely than not, >50â100%; about as likely as not, 33â66%; unlikely, 0â33%; very unlikely, 0â10%; extremely unlikely, 0â5%; and exceptionally unlikely, 0â1%.â The findings of exposure should be weighed against the evidential support based on confidence in the findings and the associated uncertainty. Results can be presented with some measure of uncertainty or assigned a level of confidence, for example, using cartographic hashing when displaying the hazard layers on a map where there is significant agreement across models of the future change or described with terms such as âlikelyâ representing 66% to 100% probability of the likelihood of the outcome. When considering non-climate-related conditions, the uncertainty is significantly low for events that occur frequently, increasing confidence in expected exposure. When an event occurs with some regularity, then historical data can be used, assuming there is no reason to believe amplification of dampening of events in the future. For rare events, expert judgment or modeling can provide information on future events and the associated uncertainty.
Maturity Factor Level 1 (1 point) Level 2 (2 points) Level 3 (3 points) 5.1 Have you established a working group for a system-wide assessment? We have identified agency participants and formed an ad hoc working group to guide the hazards and threats analysis scope and milestones. Our working group is largely composed of internal unit representatives. We have formed a formal working group to guide the hazards and threats analysis scope and milestones. The working group has identified key technical capabilities to support this self-assessment and enlisted representatives from other agencies to participate in the working group. The working group has (or will) prioritize the recommendations from the analysis. We have achieved Maturity Level 2. In addition, the working group has formed subcommittees as needed to draw on external technical experts to support the technical assessment, including experts on climate science, environmental impacts, and cybersecurity specialists. The working group has also identified roles and responsibilities for implementing the findings, including establishing an ongoing institutional responsibility for the working group. 5.2 Have you identified natural hazards that may impact your transportation system? We have reviewed hazard mitigation plans and reached out to our agencyâs maintenance staff for their knowledge of past âhot spotsâ of exposure. We have also reviewed guidance documents on asset sensitivity to hazards such as those available on FHWAâs website (U.S. DOTâs Sensitivity Matrix). We have achieved Maturity Level 1. In addition, we have reviewed after- action reports and analyzed maintenance response records to identify past events that resulted in disruptions to the transportation system. We have achieved Maturity Level 2. In addition, we have analyzed future climate changes that might affect the transportation system. This includes reviewing national, state, and local hazard reports and reaching out to specialists (e.g., climate scientists) and other experts on individual stressors. 5.3 Have you identified physical or human- caused threats that may impact your agency? We are aware of the types of physical threats that confront the agency and its employees, including concerns about crime, terrorism, assault, and those relating to CBRNE (chemical, biological, radiological, nuclear, and explosives). This awareness lies primarily in the operations unit in our agency. We maintain a security awareness program. We have achieved Maturity Level 1. In addition, we have consulted with outside professionals in law enforcement, Department of Homeland Security (DHS), Transportation Security Administration (TSA), the transportation security industry, and public health agencies to identify specific threats to our agencyâs assets and operations. We have achieved Maturity Level 2. In addition, we participate in a working group(s)/coordinating committee(s) consisting of security, enforcement, transportation, public health, and other sector representatives whose focus is on protecting critical infrastructure and mission-critical operations. We actively participate in the development and updates of the State Hazard Mitigation Plan. We also participate in field exercises and drills that simulate physical attacks against transportation infrastructure. 5.4 Have you identified cyber threats to your agency? We have reviewed resident information technology (IT) systems and the potential targeting against these systems. The history of attacks against each system has been documented. We have achieved Maturity Level 1. In addition, we have consulted with outside professionals in government and industry to identify all information system weaknesses and points of failure. We have achieved Maturity Level 2. In addition, we have considered how cyber threats may evolve in the future. This includes maintaining constant vigilance through daily assessments of the âInternet of Thingsâ (IoT) and the cyber universe. We have engaged âwhite-hatâ hackers to attack our IT systems to determine weaknesses. Table 14. Assessment table for Step 5: Understand the Hazards and Threats.
5.5 Have you identified relevant hazard metrics by asset type? We have reviewed design manuals to infer critical thresholds applicable to each asset type. We have used these resources to identify the hazard metrics and thresholds that, if exceeded, could damage our assets. We have achieved Maturity Level 1. We have also interviewed our engineers to gain additional understanding and knowledge regarding design and failure thresholds. We have investigated how asset types were impacted during past events, including examining after- action reports. We have achieved Maturity Level 2. In addition, we have reviewed empirical research, engineering studies on asset failures as well as other technical references. This information has been incorporated into our metrics and standard design procedures. 5.6 Have you collected geographic information system (GIS)-based transportation asset data necessary to perform an exposure analysis? We have developed an asset data inventory for pavement and bridges that includes location, condition, and use. Assumptions have been made to fill in gaps as needed. We have developed written documentation describing how the data were collected and incorporated into our GIS systems. We have achieved Maturity Level 1. In addition, our GIS database includes location data and characteristics on the next most important asset types (such as culverts or other drainage treatments). The data are considered complete and are updated on a set schedule. The data attributes have also been screened to support linking hazards to the asset thresholds. All datasets are accurately georeferenced to elevation data and other relevant data sources. We have achieved Maturity Level 2. In addition, our GIS database includes auxiliary assets (e.g., signage, guard rails, ITS, lights, weigh stations, rest areas, geotechnical hazard mitigation measures, etc.). These assets may also include protective measures such as geotechnical assets including retainer walls, safety netting, guard pillars, and so on (where guard pillars protect against vehicular terrorism and slope instability). The data are updated at least every 2 years. 5.7 Have you evaluated the current and future spatial extents of the natural hazards facing your agency? We have collected/developed GIS data showing the areas currently susceptible to all identified hazards. We have used available tools to project how hazards may change over the life span of our assets. This entails using past conditions to assess the likelihood of the hazards and threats occurring. For example, assume a precipitation event that has a 1% chance of occurring in any given year is projected to occur with significantly more frequency in the future or the likelihood of a winter storm occurring in a given year. For climate change, projections are based on the worst- case emissions scenario using the ensemble average of GCMs. We have collected/developed GIS data showing the areas currently susceptible to all identified hazards. We have used available tools to project how hazards may change over the life span of our assets. For climate change, projections are based on multiple scenarios to capture emissions uncertainty and provide median and extreme climate model projections to capture model uncertainty. When possible, we have estimated the probability of the hazards occurring. We have achieved Maturity Level 2. In addition, we have applied models to map those hazards that are not directly provided by models (e.g., the use of climate models for drought, surge, landslides, wildfires, etc.). When possible, we have estimated the probability of the modeled projections. We consider the interaction amongst hazards when estimating potential impacts (e.g., How likely is it that two hazards occurring sequentially or in tandem will exacerbate resulting impacts?) and used this information to identify which (if any) combinations of hazards and threats pose a significant concern. We have also considered human influences on the environment (e.g., levees and dams, changes in impervious surfaces, etc.) that can amplify/dampen the hazards. (continued on next page)
Maturity Factor Level 1 (1 point) Level 2 (2 points) Level 3 (3 points) 5.8 Have you identified transportation assets exposed to natural hazards? We have identified assets that exceed specified thresholds of the observed/projected hazards and threats. This information is captured in a GIS database. For those hazards where future thresholds might be reached (e.g., when precipitation levels might create flood-critical flows), we have included the estimated length of time before such thresholds are likely reached (e.g., within the next decade, by mid- century, etc.). This is done by overlaying the time of exceedance with the design life of the asset. We have achieved Maturity Level 1. In addition, we have included in the GIS database the degree to which the hazards exceed the critical thresholds. We have further indicated the levels of certainty and confidence of exposure. Our database also includes information on the past occurrence of hazards and threats over at least the past 20 years. We have developed metadata for all of this data in the GIS database. We have achieved Maturity Level 2. In addition, we have evaluated exposure from a systems perspective (not just asset-by-asset) across the transportation network. 5.9 Have you developed written documentation that describes the data, methodologies, and findings of the exposure analysis? We have written documentation of the data used, our methodologies, and findings in the form of technical memoranda. There is a single document that comprehensively describes all aspects of the exposure assessment. The working group has reviewed the document. We have achieved Maturity Level 2. In addition, we have produced a publicly available document that is graphically rich and aimed at a broader nontechnical audience. Score Range Description of Agency Maturity in Understanding the Hazards and Threats 0 to 12 Your agency is emerging into this area and has taken initial steps to begin to understand and document potential hazards and threats to your transportation system. 13 to 23 Your agency has implemented several activities for understanding the hazards and threats, capturing the geospatial relationship between assets and hazards/threats. 24 to 27 Your agency has reached significant maturity in understanding your hazards and threats. The major focus should be on maintaining and enhancing existing efforts when appropriate and taking advantage of enhancing and validating current practices whenever possible. Table 14. (Continued).
Understand the Hazards and Threats (Step 5) 87  Recommended Actions to Maintain the Highest Level of Agency Resilience Capability The highest level of capability for Step 5: Understand the Hazards and Threats focuses on continual improvement in agency capability and actions to understand and quantify which hazards and threats affect your assets. If your agency has reached Maturity Level 3, the steps that can be taken to maintain this level include: ⢠Periodically reassessing the effectiveness of your agencyâs working group. Adjust membership of the group based on the results of the analysis, adding members and expertise that will be necessary given projected future hazards. ⢠Periodically reassess the identification of hazards and threats that could impact your system. This includes engaging with emergency management staff as well as hazard/threat experts. Update the hazard and threat exposure layers as new information, methodologies, and data become available. ⢠Periodically review the asset data available and consider opportunities to expand the asset information that would fill in any gaps that exist for effectively assessing asset damage and/or ensure updates to existing information. ⢠Incorporate after-event information into a database to be used for future vulnerability and risk assessments. Use these data to continue to refine and calibrate your methods and approaches. ⢠Stay abreast of developmentsâespecially in new data sources and analysis methodsâthat could be applied in the next update of your exposure analysis. This could include staff attendance at specialty conferences, workshops, peer exchanges, and staff training/professional development. If you did not score a 27 in the assessment (a perfect score in Level 3 efforts), identify those factors that were rated lower and identify a strategy or action steps to improve these particular components of Step 5. Recommended Actions to Achieve Higher Levels of Resilience Capability If you scored at the lowest level, you are just starting your evolution toward a more resilience- oriented agency. In such a case, the top managers of the agency should identify which of the factors in Table 14 were most lacking and determine priorities for better understanding hazards and threats. Table 15 is offered as a template to determine which actions your agency can take to improve its resilience capabilities, who should be responsible, the timeframe for implementation, and the expected outcomes. Letâs do this. (check) Action Re sp on si bi lit y? Ti m ef ra m e? Ex pe ct ed ou tc om es ? Develop a full and complete asset inventory, including asset location, condition, and use. Over time, this asset inventory should include all assets for which your agency is responsible. Collect and assess hazard and threat data and estimate the likelihood of the event occurring in the future (including noting the uncertainty in results as appropriate). Table 15. Actions to achieve higher maturity for Step 5: Understand the Hazards and Threats. (continued on next page)
88 Mainstreaming System Resilience Concepts into Transportation Agencies: A Guide Chapter 7 References FHWA. 2017. Vulnerability Assessment and Adaptation Framework, 3rd ed. FHWA Report. FHWA-HEP-18-020 Washington, DC. Retrieved June 30, 2020, from https://www.fhwa.dot.gov/environment/sustainability/ resilience/adaptation_framework/ IPCC. 2014. Climate Change 2014: Synthesis Report: Contribution of Working Groups I, II and III to the Fifth Assessment Report of the Intergovernmental Panel on Climate Change [Core Writing Team, R.K. Pachauri and L.A. Meyer (eds.)]. IPCC, Geneva, Switzerland. MassDOT-FHWA. 2015. Chapter 4. In Pilot Project Report, Climate Change and Extreme Weather Vulnerability Assessments and Adaptation Options for the Central Artery. https://www.mass.gov/files/documents/2018/ 08/09/MassDOT_FHWA_Climate_Change_Vulnerability_1.pdf National Climate Assessment. (n.d.) Sea Level Rise. Website. Retrieved March 17, 2021, from https://scenarios. globalchange.gov/sea-level-rise NOAA. n.d. Storm Events Database. Website. National Centers for Environmental Information. Retrieved March 17, 2021, from https://www.ncdc.noaa.gov/stormevents/. Letâs do this. (check) Action Re sp on si bi lit y? Ti m ef ra m e? Ex pe ct ed ou tc om es ? Collect maintenance records and other cost information for use in identifying likely hazards and the costs of responding. Identify susceptibility factors that may worsen or reduce the system disruption caused by expected hazards. Produce GIS mapping of hazard exposure across all assets in the transportation system for each hazard and threat. Identify the assets as most-exposed across hazards and threats. Identify the mission-critical operations at most risk across hazards and threats. Map system-scale disruptions for each hazard and threat. Develop quantifiable hazard-to-impact relationships that are tailored to your geographic location and asset class. Increase engagement and strengthen relationships internally with asset managers, engineers, emergency management, and GIS specialists. Increase engagement and strengthen relationships externally with governmental and university climate science research centers, state climatologists, health professionals, cyber and terrorist experts, geotechnical experts, and sector experts. Work with representatives from other sectors that affect and are affected by disruptions to respective networks. Identify potential points of vulnerability and collaboratively identify strategies for minimizing failure. Possible steps for Step 4: Implement Early Wins Table 15. (Continued).
Understand the Hazards and Threats (Step 5) 89  U.S. DOT. 2019. Colorado DOT offers lessons learned after recovering from two 2018 ransomware attacks. Intelligent Transportation Systems Joint Program Office. Retrieved March 28, 2021, from https://www.itskrs. its.dot.gov/its/benecost.nsf/ID/182bf1869996a8578525838c0070b645?OpenDocument=&Query=Home Useful Resources DHS. 2010a. DHS Transportation Systems SectorÂSpecific Plan: An Annex to the National Infrastructure Protection Plan. Washington, DC. Retrieved June 30, 2020, from https://www.dhs.gov/xlibrary/assets/nipp-ssp- transportation-systems-2010.pdf DHS. 2010b. Review of the Department of Homeland Securityâs Approach to Risk Analysis. Washington, DC. Retrieved June 30, 2020, from https://www.nap.edu/download/12972 European Commission. 2018. JRC Technical Report: Mapping of Risk WebÂPlatforms and Risk Data: Collection of Good Practices. Luxembourg: Publications Office of the European Union. Retrieved June 30, 2020, from https://publications.jrc.ec.europa.eu/repository/bitstream/JRC109146/mapping_of_risk_web-platforms_ and_risk_data_online_final.pdf FEMA. 2016. State Mitigation Planning Key Topics Bulletins: Risk Assessment. Washington, DC. Retrieved March 28, 2021, from https://www.fema.gov/sites/default/files/2020-06/fema-state-mitigation-strategy- planning-bulletin_10-26-2016_0.pdf FHWA. 2014a. Transportation Climate Change Sensitivity Matrix. Website. Washington, DC. Retrieved March 28, 2021, from https://toolkit.climate.gov/tool/transportation-climate-change-sensitivity-matrix FHWA. 2014b. Highways in Coastal Environment: Assessing Extreme Events. Hydraulic Engineering Circular No. 25, Volume 2. Washington, DC. Retrieved June 30, 2020, from https://www.fhwa.dot.gov/engineering/ hydraulics/pubs/nhi14006/nhi14006.pdf FHWA. 2015. Climate Change Adaptation Guide for Transportation Systems Management, Operations, and Maintenance. Washington, DC. Retrieved June 30, 2020, from https://ops.fhwa.dot.gov/publications/ fhwahop15026/fhwahop15026.pdf FHWA. 2016. Highways in the River Environment â Floodplains, Extreme Events, Risk, and Resilience. Hydraulic Engineering Circular No. 17, 2nd Edition. Washington, DC. Retrieved June 30, 2020, from https://www. fhwa.dot.gov/engineering/hydraulics/pubs/hif16018.pdf MassDOT. 2017. Technical Report for the Massachusetts Sea Level Rise and Coastal Flooding Viewer. Boston, MA. Retrieved June 30, 2020, from https://www.mass.gov/files/documents/2016/10/qs/flood-viewer-tech- report.pdf Van Westen, C. J. 2013. Remote Sensing and GIS for Natural Hazards Assessment and Disaster Risk Management. Retrieved March 28, 2021, from https://www.researchgate.net/publication/285929471_Remote_Sensing_ and_GIS_for_Natural_Hazards_Assessment_and_Disaster_Risk_Management Willis, H. H., et al. 2018. Homeland Security National Risk Characterization â Risk Assessment Methodology. Retrieved June 21, 2020, from https://www.rand.org/content/dam/rand/pubs/research_reports/RR2100/ RR2140/RAND_RR2140.pdf
