National Academies Press: OpenBook

Risk Assessment Techniques for Transportation Asset Management: Conduct of Research (2023)

Chapter: Section 5 - Summary of State of the Practice

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Suggested Citation:"Section 5 - Summary of State of the Practice." National Academies of Sciences, Engineering, and Medicine. 2023. Risk Assessment Techniques for Transportation Asset Management: Conduct of Research. Washington, DC: The National Academies Press. doi: 10.17226/27130.
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Suggested Citation:"Section 5 - Summary of State of the Practice." National Academies of Sciences, Engineering, and Medicine. 2023. Risk Assessment Techniques for Transportation Asset Management: Conduct of Research. Washington, DC: The National Academies Press. doi: 10.17226/27130.
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Suggested Citation:"Section 5 - Summary of State of the Practice." National Academies of Sciences, Engineering, and Medicine. 2023. Risk Assessment Techniques for Transportation Asset Management: Conduct of Research. Washington, DC: The National Academies Press. doi: 10.17226/27130.
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Suggested Citation:"Section 5 - Summary of State of the Practice." National Academies of Sciences, Engineering, and Medicine. 2023. Risk Assessment Techniques for Transportation Asset Management: Conduct of Research. Washington, DC: The National Academies Press. doi: 10.17226/27130.
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Suggested Citation:"Section 5 - Summary of State of the Practice." National Academies of Sciences, Engineering, and Medicine. 2023. Risk Assessment Techniques for Transportation Asset Management: Conduct of Research. Washington, DC: The National Academies Press. doi: 10.17226/27130.
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Suggested Citation:"Section 5 - Summary of State of the Practice." National Academies of Sciences, Engineering, and Medicine. 2023. Risk Assessment Techniques for Transportation Asset Management: Conduct of Research. Washington, DC: The National Academies Press. doi: 10.17226/27130.
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Suggested Citation:"Section 5 - Summary of State of the Practice." National Academies of Sciences, Engineering, and Medicine. 2023. Risk Assessment Techniques for Transportation Asset Management: Conduct of Research. Washington, DC: The National Academies Press. doi: 10.17226/27130.
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Suggested Citation:"Section 5 - Summary of State of the Practice." National Academies of Sciences, Engineering, and Medicine. 2023. Risk Assessment Techniques for Transportation Asset Management: Conduct of Research. Washington, DC: The National Academies Press. doi: 10.17226/27130.
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Suggested Citation:"Section 5 - Summary of State of the Practice." National Academies of Sciences, Engineering, and Medicine. 2023. Risk Assessment Techniques for Transportation Asset Management: Conduct of Research. Washington, DC: The National Academies Press. doi: 10.17226/27130.
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Suggested Citation:"Section 5 - Summary of State of the Practice." National Academies of Sciences, Engineering, and Medicine. 2023. Risk Assessment Techniques for Transportation Asset Management: Conduct of Research. Washington, DC: The National Academies Press. doi: 10.17226/27130.
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Suggested Citation:"Section 5 - Summary of State of the Practice." National Academies of Sciences, Engineering, and Medicine. 2023. Risk Assessment Techniques for Transportation Asset Management: Conduct of Research. Washington, DC: The National Academies Press. doi: 10.17226/27130.
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13   The state of the practice, summarized here, documents how existing and potential approaches can be used to integrate enterprise-, network-, and program-level risk analysis. The research team reviewed effective processes by summarizing the legislative requirements and the risk manage- ment practices documented in the states’ TAMPs and interviewing selected state agency officials who indicated they had notable risk management practices. The summary includes the current state of bridge and pavement modeling to support multi-objective, cross-asset investment deci- sion making under conditions of uncertainty. The complete state of the practice assessment is provided in Appendix C. A general observation is that elements of risk-based asset management are scattered through- out the literature and transportation asset management guides, policies, and practices. However, they are not summarized into an overall framework that could be used as is for managing risk throughout the asset management process. With the 23 CFR 515 requirements, DOTs had to develop formal asset management plans. In their TAMPs, DOTs are acknowledging the impor- tance of risk management of assets and are increasing the engagement of agency personnel and leadership in developing and implementing TAMPs. This increased awareness is a step toward maturating asset risk management. The state of the practice assessment resulted in several conclusions that directly led to the tools and approaches developed in later stages of NCHRP 08-118: • The FHWA asset management plan requirement in 23 CFR 515 led all states to assess risks to their assets, which gave the states at least a basic level of risk management understanding. • However, risk management was often limited to one section of TAMPs and did not appear to be ingrained into states’ overall asset management practices. • Interest in managing risks from climate change is growing as many states are developing tools. • However, risk management and climate risk assessment were developing on separate paths. • States were not using the latent ability of BMSs and PMSs to assess risk. • Management systems were used to assess conditions, not risks. 5.1 Survey and Interview Summaries A short survey was deployed to gather information about tools and techniques state transpor- tation agencies used and/or developed to manage risks to assets. Twenty-two DOTs submitted responses (two DOTs provided responses from two SMEs). The survey responses were analyzed, and follow-up interviews were conducted when the responses indicated the DOT used or devel- oped tools to manage risks to assets. S E C T I O N 5 Summary of State of the Practice

14 Risk Assessment Techniques for Transportation Asset Management: Conduct of Research The survey requested that state DOTs rate their agencies’ asset risk management maturity based on the following general guidelines: • Emerging: There is an understanding of risk management but there has been no implementa- tion yet. • Low: The agency conducts risk assessment but does not incorporate risk management into decisions yet. • Medium: Risk management is occurring for high-value assets such as bridges and pavements. • High: Asset risk is considered in planning, programming, and project delivery of high-value assets such as pavements and bridges. • Very high: Risk management is institutionalized and is a routine part of decision making in the agency. • Uncertain: The respondent is not sure of the agency’s maturity level. None of the DOTs selected “uncertain” as the rating for their agency’s asset risk management maturity. The 22 DOTs ranked their risk-based asset management maturity as follows: • Fifteen rated the DOT’s maturity as medium. • Five rated the DOT’s maturity as high. • One rated the DOT’s maturity as very high. • One rated the DOT’s maturity as low. The survey responses reflected that all 22 DOTs apply risk management to pavements and bridges. The following is a summary of information gathered from the survey responses, follow-up interviews and e-mail exchanges, a literature review, and reviews of all 52 2019 TAMPs. 5.2 Risk Management Practices in the 2019 TAMPs The following are risk management practices or trends evident in the 2019 TAMPs, plus addi- tional information gathered from interviews and a review of agency documents. • Many states appear to have conducted their first risk assessments in 2018 and 2019 to comply with the asset management regulation. The TAMPs reveal that all 52 transportation agencies were exposed to risk management, understand its definition, and have undertaken a prelimi- nary assessment of risks to their assets. • Several states, such as Minnesota, Washington, Vermont, and California, reported having for- mal asset management risk programs for several years and have iterated several risk analysis efforts. • Idaho and New York report having formal enterprise risk management programs that manage some elements of risk to assets but whose primary focus is broader enterprise risk management. • Several states capitalize on risk elements of the NBI data to evaluate risks to bridges, such as whether they are scour critical, are fracture critical, would create lengthy detours if they fail, are closed, or are load limited. These NBI risk items are incorporated into several bridge pri- oritization processes. • Risk considerations are less common in pavement management processes. • Some programs to manage at-risk assets, such as seismically vulnerable structures or unstable slopes, have been in place for decades. • Similar programs are emerging for other at-risk assets, such as those at risk of sea level rise, more intense precipitation, and more intense heat. Several TAMPs discussed new tools to help manage these assets at risk of a changing climate. • Several TAMPs provided examples of other at-risk assets such as inventories of aging concrete pavements, high-cost aging bridges, or deep stormwater tunnels.

Summary of State of the Practice 15   • What could be described as “qualitative risk management,” in which the judgments of staff are used to assess risks, was common in the TAMPs. Common risks cited in the TAMPs included – Uncertain funding and purchasing power – Loss of staff expertise – Likelihood of diminishing political or organizational support for asset management – External threats such as rising sea levels, higher temperatures, and more intense rainfall – Locally controlled National Highway System (NHS) assets managed by underfunded local agencies that do not prioritize the NHS over other local routes – At-risk asset subgroups, such as roads and bridges subject to flooding, critical asset classes, and high-cost assets • What could be described as “quantitative risk assessment,” in which costs or other numeric values were calculated, was rare except for – Capturing some risk-based values related to bridge elements – Estimating threats caused by climatic events, such as increased temperatures and rainfall events 5.3 Risk Management Practices for Managing Climate, Weather, and Environmental Risks Overall, the general level of maturity in managing climate change risks is growing. Early efforts include agencies using geographic information systems (GIS) to assess vulnerable locations and prioritizing efforts to strengthen at-risk assets such as culverts and slopes. While some agencies have conducted risk assessments, fewer have incorporated the results into enterprise-wide decision making. Differences in maturity may be attributed to capacity, resource availability, leadership engagement, or the recentness of extreme events. Some agencies have inte- grated resilience considerations only on an ad hoc basis. Other agency planning, programming, and project delivery actions indicate that several practices are emerging for systematic change in risk management: • Integrating resilience considerations into project evaluation criteria • Considering resilience when evaluating future transportation and land use scenarios • Integrating resilience into corridor studies • Developing dedicated funding streams for resilience projects • Conducting benefit–cost assessments to determine the preferred level of resilience investment • Incorporating natural hazard risk screening as part of project initiation forms • Developing climate change guidance • Considering climate change risks in the environmental review process • Incorporating resilience into emergency management planning • Integrating climate change projections into deterioration modeling Among the specific practices states reported were • Developing a flooding database to identify vulnerable locations and prioritize them for improvements • Collecting GIS data to evaluate vulnerability and risk for DOT assets • Forming a resiliency working group to evaluate current design standards, policy, and practices and to recommend changes to address climate change and weather-related risks • Participating in an FHWA extreme weather and proxy indicators pilot study, which resulted in the proposal to develop a resiliency system management tool to map and analyze loca- tions vulnerable to extreme weather events, as well as environmental, socioeconomic, and other factors

16 Risk Assessment Techniques for Transportation Asset Management: Conduct of Research • Developing an environmental resiliency tool that uses a visualization application to map assets where sea level rise affects bridge and pavement investments • Creating a corridor risk management process that could assess risks such as flooding, rockfall, earthquakes, and wildfires by corridor • Using GIS to review vulnerability data and analyze the sea level rise impacts in the project environmental review process • Prioritizing bridges prone to scour risk • Developing metrics and models that incorporate risk, such as a level of risk score for geohazard sites and a pavement model that makes different investment decisions based on roadway category • Using a slope vulnerability model in GIS to identify at-risk slopes • Using GIS to identify geographic areas across the state to assess locations in the transportation network that may be more vulnerable to weather-related risks • Incorporating risks into designs and specifications for sizing culverts • Developing a culvert prioritization tool that creates a vulnerability index based on streamflow and geomorphology • Calculating risk scores for roadway locations subject to rockfall and mitigating high-risk areas, subject to funding availability • Developing a statewide climate change vulnerability assessment tool that will include maps and, potentially, new data sets that identify high-risk corridors and those assets most at risk • Deploying a web-based application to identify bridges, culverts, and road embankments vulnerable to damage from floods, estimate risk based on the vulnerability and criticality of roadway segments, and identify potential mitigation measures based on the factors driving the vulnerability • Conducting FHWA extreme weather risk pilots • Developing an extreme weather risk register 5.4 State of the Practice for Incorporating Risk Analysis into Management Systems The surveys, literature reviews, and interviews did not reveal that many agencies were using their management systems to model risk. Nor was there evidence of risk analysis using systems other than BMSs and PMSs. There are, however, encouraging signs that agencies are starting to better link overall risk concepts of resilience and vulnerability to asset management planning more generally. It is apparent from interviews with states and management system vendors that the main pavement and bridge management vendors are not focused on implementing risk functionality specifically. The reasons for this can be summarized for pavement and BMSs separately. 5.4.1 Bridge Management Systems Most U.S. transportation agencies do not have operational large-scale bridge management systems that meet the requirements of 23 CFR 515.17. As a result, the agencies are focused on implementing and operationalizing basic BMSs. As part of this process, agencies are concentrat- ing on implementing systems that maximize various condition-based indices and utility func- tions. They are incorporating risk only indirectly by weighting benefits of improvement actions by factors such as traffic that are surrogates for consequence. It is likely that, until these first implementations concentrated on condition objectives are complete, risk will not be incorporated more explicitly into overall utility and objective func- tions. Nonetheless, based on such work as NCHRP 20-07/Task 378, “Assessing Risk for Bridge

Summary of State of the Practice 17   Management,” there is a well-documented framework that could be incorporated into bridge management once agencies are mature enough with their bridge management implementations. States reported several relevant uses of management systems: • DOTs can use the risk assessment capabilities within BMSs and PMSs. Because management systems can incorporate inputs that affect asset condition, the risks surrounding the inputs can be analyzed. Inputs such as investment levels, unit costs, deterioration rates, loadings, and other factors can be modeled using these systems. The degree of influence of each input on asset condition reflects either opportunities or threats. For example, given a fixed budget, DOTs can use management systems to assess the risks attributable to rising unit costs or the opportunity attributable to falling unit costs. • DOTs can use management systems to optimize scenarios by designating risk factors as objec- tive functions. For example, an objective function could be to reduce the risk of the number of structures that are load limited, or fracture critical, or subject to scour. An objective function can be used to optimize investment strategies in order to reduce these risk factors. • Currently, vendors are not focused on implementing any specific risk functionality in their software. • Whether a structure was on an evacuation route was not included as a factor in any BMS analysis. • Several DOTs used or planned to use various attributes collected as part of the NBI inspec- tions, but fewer used or planned to use attributes not currently in the NBI. • Condition and traffic were the most common factors that ranked high in addressing risk. • Detour length and scour were the next two factors considered. • Seismic and fracture-critical attributes were also factors considered. 5.4.2 Pavement Management Systems Most pavement management systems have been in place for many years, and the use of PMSs in many agencies is mature. Risks related to sea level rise, flooding, hurricanes, and other natural disasters are not being considered in pavement modeling, possibly because pavement managers have not been thinking in terms of these risks and are more concentrated on asset condition deterioration. This is understandable, as pavements do not initially appear especially vulnerable to such threats. However, when considering mitigation actions such as raising the road or miti- gation actions that are not directly related to the road itself but to the culverts under the road or the stability of cut and fill slopes in heavy rains, modeling of these mitigation actions and the vulnerabilities they mitigate could be a much larger part of the management of roadways. As a result, there may be considerable opportunity to extend, for instance, the framework laid out in NCHRP 20-07/Task 378 and combine it with other frameworks such as the FHWA Vulnerability Assessment and Adaptation Framework2 to incorporate other risks into PMSs. This will require the development of guidelines and considerable outreach efforts, including training and pilots, to become widespread. 5.4.3 Potential for Management Systems to Assess Risk Although the surveys, interviews, and literature review did not reveal widespread use of man- agement systems to assess risk, the management systems possess the potential to do so. One of the fundamental capabilities of management systems is to model one or more metrics for any sequence of treatment actions over time. This is accomplished by modeling the deterioration of any number of indices. In addition to modeling the deterioration of the indices, the systems model improvements to these assets such that any treatment is associated with either a direct improvement or a reduction in the deterioration rate. These indices can then be aggregated into a

18 Risk Assessment Techniques for Transportation Asset Management: Conduct of Research single index (also called a utility function) that can be maximized or minimized over time using optimization analysis. Management systems can model metrics or indices that are surrogates or proxies for risks. Examples could include scour criticality, vulnerability to seismic or geotechnical events, impacts such as detour lengths, average daily traffic (ADT), or potential for damage from flooding or sea level rise. Each of these risks can be modeled and their reduction optimized, as with pavement or bridge deterioration. The ability to model risk metrics over time is already incorporated into one of the more common asset management systems, AASHTOWare BrM bridge management software. Factors that BrM can assess include ADT, channel conditions, fracture criticality, weight-limit posting, scour, under clearances, and waterway adequacy. This functionality allows practitioners to map values of NBI attributes such as ADT and scour criticality to a utility value. Then AASHTOWare BrM can use weighting to amalgamate these utility values up to a more general risk utility value. Finally, this risk utility, or index, can be incorporated into a higher-level overall objective. Users could model investment strategies that minimized these conditions, just as they could model how to minimize overall bridge deficiencies. Other common asset management systems are more general and provide frameworks that support any point-in-time index calculations from modeled subindices. These calculations can also be rolled up to an overall index that can be used as an objective function to be maximized or minimized during optimization. The overall effect is therefore similar. However, these other systems, such as Deighton dTIMS and AgileAssets Structures Analyst and Pavement Analyst, do not explicitly provide a specific function to model risk over time. In concept, risk is a point-in-time metric that can be calculated for any set of assets in the same way as a condition metric. Using the management framework described in Section 5.4.2, the vulnerability of a bridge to being washed out in a certain magnitude of storm can be linked to a metric relating to scour. Similarly, the consequence of the washout can be modeled as a metric, relating to ADT and detour length. Based on a definition of risk being a function of likelihood and consequence, the general functionality provided by common asset management systems enables the development of risk indices. Risk would be a function of various factors such as ADT and scour criticality. This level of risk can be modeled over the course of a sequence of risk mitigation actions. Like a condition index, an overall risk index could be modeled in various management systems to result in an overall average (or other statistic) of the risk level and overall average cost to maintain that level. The ability of various models to optimize investments to reduce risks reflects their ability to capitalize on risk-related factors captured by the NBI. The state of the practice report notes that bridge engineers have managed risk for decades, even if the term “risk” was not commonly used. Among the NBI items related to risk are detour length, functional classification, year built, ADT, design load, scour, fracture criticality, under clearance, channel adequacy, abutment protection, and even the overall condition ratings of good, fair, and poor. Many states’ bridge prioritization processes include one or more of these factors. 5.4.4 Capitalizing on Bridge Risk Data The state of the practice report highlights several bridge management processes that build on NBI data, such as those mentioned for detour length, functional classification, fracture criticality, and scour.

Summary of State of the Practice 19   The Minnesota Department of Transportation’s (MnDOT) Bridge Replacement and Improve- ment Management System includes a risk assessment element called the Bridge Planning Index (BPI). The BPI treatment logic considers factors such as bridge width, vertical clearance, design live load, and historical design details. It also includes risk factors that determine the probability of a service interruption, as well as four factors that create an importance factor. All this informa- tion is used to create candidate lists of bridge projects.3 The Delaware Department of Transportation (DelDOT) 2019 TAMP included the Bridge Health Index, a risk-based bridge deficiency formula based on several NBI items. The DelDOT TAMP states that the agency developed the bridge deficiency formula to assist in ranking bridges most at risk, rather than only those in the poorest condition.4 The formula is based on two prin- ciples, structural capacity of the structure and user demand for the structure. Structural capacity is the structure’s ability to carry vehicle loads, the condition of bridge components, and the type of bridge. User demand is based on traffic volume, length of potential detour if closed, and restric- tions on the truck weights and classification of the roadway. Historical significance and suscepti- bility to scour and friction are also factors. When fully implemented, the Bridge Health Index will also indicate the condition state of the bridge based on the condition state of each bridge element. The New York State Department of Transportation (NYSDOT) TAMP states that in its BMS a portion of a structure’s prioritization score is determined by its hydraulic vulnerability. Detour length is also a contributing decision factor. NYSDOT also has a GIS-based tool that identifies known flooding-vulnerable locations on state-owned roads.5 5.5 Identification of At-Risk Assets and Asset Groups The state of the practice document identified many practices representative of an increasing focus on managing risks to assets: • Wave Vulnerability: Following hurricane impacts on bridges in 2004 and 2005, the Florida Department of Transportation (FDOT) conducted studies of wave vulnerability to mitigate wave damage to structures. Some of the factors that affect storm surge are bay bathymetry, storm direction, storm duration, fetch, tides, current, and horizontal channel restrictions. Storm surge will vary depending on these parameters. A study of bridges in Tampa Bay deter- mined that depending on storm surge, wave height, and current speed, many bridges in Florida could be destroyed by wave action and there is no practical way to strengthen them. FDOT then determined the location of all wave-vulnerable state bridges in Florida and developed emergency response plans. The plans anticipate responses for the possible damage to or loss of bridges and include detour plans, emergency contacts, utility disruption, boat landings, ferry slips, and resource availability. New bridges are designed to clear storm surge heights or to resist wave action forces. FDOT continues to prioritize operations and mainte- nance activities, such as culvert maintenance, that contribute to risk mitigation. It also devel- oped emergency response plans that emphasize active monitoring and management, such as bridge scour monitoring before, during, and after flooding events. FDOT will continue to prepare for intermittent loss of service by developing alternate routes or services through system expansion and by instituting emergency detour plans. • Environmental Risk Assessment: The Maine Department of Transportation has developed a GIS-based evaluation tool called the Transportation Risk Assessment for Planning and Project Delivery (TRAPPD).6 TRAPPD uses existing data sources to evaluate multiple risks at the asset level. The tool includes an evaluation matrix of 12 questions applied to each bridge and large culvert. Questions include whether the structure is within an endangered salmon watershed or habit for protected species, in a flood plain, subject to coastal threats, within an impaired

20 Risk Assessment Techniques for Transportation Asset Management: Conduct of Research watershed, or the sole access for emergency vehicles. If any of those conditions are met, the risks they pose are considered in the project development or maintenance processes. • Slope Vulnerability: MnDOT completed a slope vulnerability study for the Twin Cities metro- politan area and southern Minnesota. As a result, a slope vulnerability model was developed using geomorphology to assess impact to MnDOT roadways. The primary causes of slope fail- ures in each region were identified, a GIS analysis applied these factors to the existing terrain, and a spatial output mapped vulnerable locations to be used in agency decision making. • Coastal Vulnerability: The Rhode Island Department of Transportation (RIDOT) 2019 TAMP notes that the state’s 400 miles of coastline and large inland watersheds are vulner- able to hazards such as sea level rise, storm surge, and flooding. In response to these threats, RIDOT participated in the development of a GIS tool called STORMTOOLS.7 The models and maps in STORMTOOLS allow illustration of the risks of coastal inundation under different sea level rise scenarios. The TAMP says that for coastal roads and bridges, even a foot of sea level rise could result in flooding and structural problems. The impact of sea level rise is even more pressing, given the many storm drainage outfalls near sea level. Significant sea level rise would swamp outfalls and cause the drains to fail. • Bridge Hardening: The NYSDOT TAMP stated that to mitigate the effects of extreme weather, the state provided $500 million in 2016 to make roadways less susceptible to flood- ing and other extreme weather events, including ice jams. Another $518 million project hardened 106 at-risk bridges against scour and flooding threats. • Flood Hazard Analysis: The Pennsylvania Department of Transportation (PennDOT) con- ducted an extreme weather vulnerability study that produced a GIS tool that highlights poten- tial flood risks.8 The Road Condition Reporting System (RCRS) enhanced with this GIS tool monitors the condition of a road and is used to identify locations of flooding vulnerabilities. The tool includes a map of all sites at risk of flooding, with each site ranked by whether it is in the top 1 percent, 5 percent, 10 percent, 15 percent, 20 percent, or 25 percent of the vulnerable sites.9 Data include the number of times each site has been closed because of flooding, its ADT, and a risk prioritization score. PennDOT also conducted a pilot in three counties to identify sites’ future potential for flooding given precipitation projections. • Analyzing Flood Plain Hazards: The Texas Department of Transportation (TxDOT) ana- lyzed the number of bridges within 100-year and 500-year flood event plains, which cross water, and have an NBI item 113 rating for scour susceptibility of 4 or less. The analysis showed that while only 2 percent of the state structures met those criteria, that 2 percent resulted in 132 bridges vulnerable to either a 100-year or 500-year event. TxDOT said it has made changes to reduce bridge scour from flood-prone areas and increased bridge heights to address potentially higher storm surge. Programmatically, resiliency efforts for riverine and coastal areas are included in planning and programming when assets need repair, rehabilita- tion, or reconstruction.10 • Corridor Risk Assessments: The Colorado Department of Transportation conducted a dem- onstration project assessing risks to the Interstate 70 corridor through the Rocky Mountains. It is the only multi-lane artery across the Rockies in Colorado and its closure results in extensive detours. The Colorado DOT assessed the corridor using the RAMCAP process, which stands for Risk Analysis and Management for Critical Asset Protection. RAMCAP multiplies factors such as estimated likelihood of an event by the financial impact of the event to develop an expected value of the cost of the risk. Colorado DOT assessed the annualized costs of risks to the I-70 corridor from avalanches, floods, fires, rockfall, landslides, and high wind. The state’s 2019 TAMP stated that the agency hopes to develop risk data for other state highways using this methodology.11 The Utah Department of Transportation developed a corridor risk assessment process appli- cable statewide. It uses publicly available data to assess risks from hazards such as flooding,

Summary of State of the Practice 21   rockfall, avalanche, debris flow, and earthquakes. The identified risks were noted and whether to mitigate them will be considered when projects are developed at those locations. • At-Risk Asset Groups: The Washington State Department of Transportation (WSDOT) iden- tified at least three groups of assets at risk of not achieving condition targets or of requiring excessive investments. First were nearly 1,000 lane miles of concrete pavement that are more than 40 years old. Second are the thousands of miles of chip seal pavements. If the chip seal pavements are not regularly and predictably treated, they are prone to failure, which would affect thousands of miles of Washington’s low-volume roads. Third were the 23 percent of the NHS roadways that are locally owned. A lack of data and investment for those routes creates risks that they will not achieve their condition targets. • Stream Hazards: The Vermont Agency of Transportation (VTrans) developed the Transpor- tation Resilience Planning Tool (TRPT) to identify bridges, culverts, and road embankments vulnerable to damage from floods; estimate risk based on the vulnerability and criticality of roadway segments; and identify potential mitigation measures based on the factors driving the vulnerability. The TRPT combines river science, hydraulics, and transportation planning methods and is applied at a watershed scale. The TRPT was developed and tested in three pilot watersheds and was ready to be applied in these watersheds to inform project scoping, capital programming, and hazard mitigation planning for state and local highways. • Legislative Requirements and International Practice: The state of the practice also sum- marized legislative requirements for risk management and reviewed international practices. Because findings from those two sections did not influence later stages of the project, they are not summarized here. Instead, the reader can find those summaries in Appendix C. 5.6 Practices for Incorporating Financial Risk The state of the practice review including the literature review and surveys did not identify many examples of state DOTs using probabilistic methods to assess the financial risks of income loss or excessive inflation. Both risks could represent substantial threats to an asset management plan. Alternatively, lower-than-expected inflation or revenues that exceed predicted levels could be opportunities. Several financial risk assessment practices were found in the 2019 TAMPs, although most did not use probabilistic tools such as Monte Carlo simulation. The 2019 Kentucky Transportation Cabinet (KYTC) TAMP addressed the financial risks to achieving its TAMP objectives.12 Financial risks addressed include uncertainty in federal and state road fund revenues, which is compounded by funding uncertainties for a major project known as the Brent Spence Bridge replacement across the Ohio River. KYTC uses a formal con- sensus forecasting group to develop annual road fund projections. This body of experts serves as a form of financial risk management by pooling forecasters’ expertise to generate a consensus revenue forecast. The Ohio Department of Transportation produces deterministic construction inflation fore- casts that also serve as a form of risk analysis.13 It produces a high, most likely, and low annual construction cost forecast for the current and subsequent four years. The literature review for NCHRP 08-118 did not identify many examples of financial risk management published by U.S. transportation departments. The lack of examples was a primary reason this project included probabilistic financial risk analysis as a tool to be tested in Task 5. Several tools lend themselves to such analysis, which is pertinent in eras of volatile inflation, as shown in Figure 5-1.

22 Risk Assessment Techniques for Transportation Asset Management: Conduct of Research Figure 5-1 illustrates the values as of Quarter 3 of 2021 from the FHWA Construction Cost Index, a composite index of highway construction costs. The sharp spikes in prices seen from 2005 to 2008 and from 2017 to 2021 illustrate the unpredictable nature of highway construction inflation. Probabilistic forecasting tools can help state DOTs better quantify the magnitude of uncertainty that can surround their construction cost forecasts. 5.7 Conclusions from State of the Practice Review The state of the practice assessment resulted in several conclusions that directly led to the tools and processes developed in later stages of the project: • The FHWA asset management plan requirement led all states to assess risks to their assets, which gave the states at least a basic level of risk management understanding. State TAMPs demonstrate that all 52 state DOTs assessed risks, developed risk registers, and identified strategies to respond to risks to their assets. • However, risk management often was limited to one section of the TAMPs and did not appear to be ingrained into states’ overall asset management practices. For example, few, if any, TAMPs discussed how the adopted investment strategies would reduce threats or capitalize on opportunities. Nor did many states in describing their assets and their condition identify which asset groups created the greatest risks. Exceptions were Missouri, singling out large bridges; Washington, aging pavements; and Minnesota, deep stormwater tunnels. Most states, however, did not note which assets merited the greatest investments to mitigate the risks they pose. Nor did the TAMPs note the risks of implementing life cycle–based investment strategies. • Interest in managing risks from climate change is growing as many states are developing tools. The state of the practice identified dozens of tools or processes states were developing to assess climatic and other threats to their assets. • However, risk management and climate risk assessment were developing on separate paths. The TAMP risk management sections often acknowledged climate risks, but the TAMPs seldom Figure 5-1. Inflation as illustrated by the FHWA Construction Cost Index, 2003–2021.

Summary of State of the Practice 23   identified strategies to protect assets from climatic or environmental threats. Also, the risk analyses used different terminology than did the climate threat analyses, even when discussing similar risks. • States were not using the latent ability of BMSs and PMSs to assess risks of asset deterioration or failure. Although management systems can optimize bridge and pavement attributes or con- ditions, those optimization techniques are not being deployed to optimize strategies that reduce risk. The management systems have latent capabilities to quantify and optimize strategies that reduce the risks around asset deterioration or failure. • Staff were not often focused on the potential for management systems to help make risk-based decisions. States are focusing on the first generation of management system application, which is to optimize conditions with available resources. The next generation of applications could be to optimize strategies that reduce threats to asset condition and performance. • Management systems were used to assess conditions, not risks. Criteria within bridge and pavement management inventories can become elements that are maximized or minimized within management system optimization routines. For example, investments to maximize the reduction of scour risk or other flood hazards could be among the scenarios produced by management systems. To do so, however, requires widespread demonstration of the potential to use management systems for risk analysis, not only for condition analysis.

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The assessment of climatic and extreme weather risks is increasingly becoming important to the operation of transportation agencies. There are easy-to-use tools and techniques that can be implemented by agencies.

NCHRP Research Report 1066: Risk Assessment Techniques for Transportation Asset Management: Conduct of Research, from TRB's National Cooperative Highway Research Program, discusses how to assess risks and summarizes 12 studies that demonstrate how to enhance the measurement of risks, quantify risks, and better link risk management processes with the appropriate tools.

Supplemental to the report are a presentation and NCHRP Web-Only Document 366: Risk Assessment Techniques for Transportation Asset Management: Appendices.

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