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From page 45... ... 45 Transportation agencies across the modes have taken different steps to integrate resilience analysis into their decision-making processes. Some agencies have developed comprehensive quantitative analysis procedures to estimate both the current level of resilience and the relative benefits and costs of candidate investments to improve resilience. Read the entire page →
From page 46... ... 46 INVESTING IN TRANSPORTATION RESILIENCE practices in response to federal or state legislation.1 Sometimes multiple factors occurring at the same time or in succession had influence. Hurricane Katrina (2005) Read the entire page →
From page 47... ... MEASURING AND MANAGING TRANSPORTATION SYSTEM RESILIENCE 47 TYPES OF METRICS USED IN PRACTICE While a single, direct measure of resilience cannot be readily developed or commonly applied, there are common elements in the methods that agencies use to evaluate their resilience to natural hazards and the likely effectiveness of strategies and actions to improve resilience. These elements include analysis methods and metrics for (1) Read the entire page →
From page 48... ... 48 INVESTING IN TRANSPORTATION RESILIENCE Vulnerability Vulnerability evaluates the effects of a specific natural hazard of a particular magnitude on an infrastructure asset or transportation service. Thus, measures of vulnerability assess susceptibility of infrastructure assets to damage by particular hazard events. Read the entire page →
From page 49... ... MEASURING AND MANAGING TRANSPORTATION SYSTEM RESILIENCE 49 same elements as "consequences" (such as costs to users) but also includes broader economic and social impacts, for example, on shippers of freight movements that are disrupted and on tourism industries due to disruptions to passenger transportation. Read the entire page →
From page 50... ... 50 INVESTING IN TRANSPORTATION RESILIENCE FIGURE 3-1 Resilience can be assessed by a matrix of criticality and vulnerability.6 Input Data and Derived Measures The resilience analysis process requires input data, such as hazards, asset conditions, and functionality. These are used in the agency's analytical process to measure (or estimate) Read the entire page →
From page 51... ... MEASURING AND MANAGING TRANSPORTATION SYSTEM RESILIENCE 51 FIGURE 3-2 Location of the FHWA pilots.7 NOTE: MPO = Metropolitan Planning Organization. FEDERAL PILOT PROGRAMS Pilot projects funded by the U.S. Read the entire page →
From page 52... ... 52 INVESTING IN TRANSPORTATION RESILIENCE learned to further develop or update its guidance documents and resilience tools. FTA conducted pilots through its Climate Change Adaptation Initiative, launched in 2011.9 The program funded pilots for nine transit agencies in seven locations.10 Each pilot identified current and future climate hazards (in particular flooding and extreme precipitation, extreme heat, sea level rise, and tropical storms and hurricanes) Read the entire page →
From page 53... ... MEASURING AND MANAGING TRANSPORTATION SYSTEM RESILIENCE 53 BOX 3-1 RAMCAP Plusa -- Basic Model Structure The RAMCAP model grew out of a 2002 White House conference on the protection of critical infrastructure. The highest priority of the more than 100 senior executives from the private sector in attendance was the creation of "an objective, consistent and efficient method for assessing and reducing infrastructure risks in terms directly comparable among the assets of a given sector and across sectors."a RAMCAP Plus is the most current version of the continuing development of RAMCAP. Read the entire page →
From page 54... ... 54 INVESTING IN TRANSPORTATION RESILIENCE Colorado DOT RAMCAP offers a systematic and quantitative framework for integrating risk and resilience, and Colorado DOT's application has particular value in that it moves the core ideas of RAMCAP into practice. Colorado DOT's "Risk and Resilience Analysis Procedure" is designed to bring natural hazards into its risk-based asset management program. Read the entire page →
From page 55... ... MEASURING AND MANAGING TRANSPORTATION SYSTEM RESILIENCE 55 Vulnerability, the second intermediate measure for annual risk, is defined as the probability of damage to an asset caused by a specific hazard. Specifically, it is "the probability of the Worst Reasonable Case occurring," assuming that a hazard event has happened. Read the entire page →
From page 56... ... 56 INVESTING IN TRANSPORTATION RESILIENCE characteristics of the people in each county.12 The criticality procedure then transforms each of the six metrics into a score from 1 to 5, which is summed with equal weighting into an overall criticality score. The criticality score is further categorized as low, medium, and high. Read the entire page →
From page 57... ... MEASURING AND MANAGING TRANSPORTATION SYSTEM RESILIENCE 57 FIGURE 3-3 The Colorado DOT is experimenting with a measure of resilience that combines measures for cumulative annual risk and criticality in a way that can assess the comparative resilience of an entire highway system. This figure shows variations in the level of resilience for segments of I-70.13 equal to 1, and hence the term drops out of the equation when the terms are multiplied together. Read the entire page →
From page 58... ... 58 INVESTING IN TRANSPORTATION RESILIENCE to produce a quantitative measure of resilience, defined as 1 divided by the product of risk and criticality. As with the Colorado DOT, the Utah DOT used pilot studies (including one focusing on I-15) Read the entire page →
From page 59... ... MEASURING AND MANAGING TRANSPORTATION SYSTEM RESILIENCE 59 FIGURE 3-4 Hazus-MH can be used to compare regional seismic risk by annualized earthquake losses.17 Transportation Systems Center.18 The FAST Act required the incorporation of resilience considerations into transportation planning, and the development of the RDRM is part of FHWA's effort to respond to that mandate. The goal of the RDRM project is to develop a "nationally replicable modeling tool that quantifies direct and indirect costs" of the kinds of disruptive events associated with natural hazards. Read the entire page →
From page 60... ... 60 INVESTING IN TRANSPORTATION RESILIENCE measures as RAMCAP models, such as hazard probabilities, vulnerability of infrastructure assets to particular hazards, and the consequences of damages to infrastructure. It is intended to be used in conjunction with the travel demand models used by metropolitan and regional planning organizations. Read the entire page →
From page 61... ... MEASURING AND MANAGING TRANSPORTATION SYSTEM RESILIENCE 61 of 1 to 4. For example, for sensitivity to higher temperatures, ballast type is one indicator for rail, and age of buses is one indicator for mass transit services. Read the entire page →
From page 62... ... 62 INVESTING IN TRANSPORTATION RESILIENCE FIGURE 3-5 Steps for the vulnerability assessment conducted by the San Diego International Airport.22 to the hazard in terms of its nature and degree. Step 2 identifies the sensitivity or "the degree to which the physical condition and functionality of an asset, population, or system is affected by climate stressors." The analysis of adaptive capacity in Step 3 requires identifying the "inherent characteristics that allow the asset to readily respond or adapt" to the stressors. Read the entire page →
From page 63... ... MEASURING AND MANAGING TRANSPORTATION SYSTEM RESILIENCE 63 FIGURE 3-6 San Diego International Airport flooding forecast due to sea level rise, maximum high tide, and 100-year storm surge.24 The San Diego County Regional Airport Authority then went beyond the vulnerability assessment to examine the consequences of the vulnerabilities identified and developed a preliminary list of initiatives to mitigate those vulnerabilities. For assets deemed vulnerable, they conducted a "highlevel risk assessment" that analyzed the potential economic, social, and environmental consequences of the damage or disruption associated with each climate stressor. Read the entire page →
From page 64... ... 64 INVESTING IN TRANSPORTATION RESILIENCE The vulnerability profiles identified, through qualitative descriptions, which specific assets are vulnerable to which stressor and during which time frame. The specificity in the vulnerability profiles allowed for the development of a corresponding list of initiatives to be implemented in the near, medium, and long term. Read the entire page →
From page 65... ... MEASURING AND MANAGING TRANSPORTATION SYSTEM RESILIENCE 65 The agency produced its first organization-wide "Resilience Indicator Framework" in 201528 and in 2020 issued a significant update.29 The agency built on a vulnerability assessment completed in 2014 and on a previous pilot project for transit indicators funded by FTA.30 The agency selected the indicators after a review of research and best practices worldwide and adapted them to be specific to LACMTA's organization and practices.31 Table 3-1 lists the technical and organizational indicators as refined in 2020. Technical indicators evaluate the performance of physical systems. Read the entire page →
From page 66... ... 66 INVESTING IN TRANSPORTATION RESILIENCE Technical Indicators Organizational Indicators Redundancy RE-01. Alternate Route/Mode Availability RE-02. Read the entire page →
From page 67... ... MEASURING AND MANAGING TRANSPORTATION SYSTEM RESILIENCE 67 Each indicator is accompanied by a grading rubric that describes a score from 1 to 4, with a score of 4 representing the highest level of resilience. For example, for the resilience design criteria indicator, the lowest score corresponds to no resilience design criteria and the highest score to "resilience design criteria have been developed and strategies have been implemented for new and upgrade/repair projects." For the alternative route/mode capacity indicator, the lowest score is assigned if the "alternate mode has <25% capacity of the failed mode during peak demand" and the highest score if the "alternate, unaffected mode has >75% capacity of failed mode during peak demand."34 The 1–4 scores are then transformed into percentages to make them easier for the public to understand. Read the entire page →
From page 68... ... 68 INVESTING IN TRANSPORTATION RESILIENCE DESIGN GUIDES The practice of resilience is, for the most part, still in the stages of customized analysis and application experimentation. Design guides are one example of how resilience may become part of the routine practices of transportation agencies. Read the entire page →
From page 69... ... MEASURING AND MANAGING TRANSPORTATION SYSTEM RESILIENCE 69 TABLE 3-2 New York City Climate Resiliency Design Guidelines Climate Change Data for Designing with Future Heat Conditions Extreme Heat Events Design Criteria End of Useful Life # of Heat Waves per Year # of Days at or Above 90oF Annual Average Temperature 1% Dry Bulb Temperature Cooling Degree Days (Base –65°F) Historic trend (1971–2000) Read the entire page →
From page 70... ... 70 INVESTING IN TRANSPORTATION RESILIENCE TABLE 3-3 Summary of Resilience Measures Used by Transportation Agencies Output Measures Intermediate Measures Input Data Annual Risk (Colorado DOT) Hazard probability Probability of rockfalls Probability of floods Probability of debris flows Vulnerability Engineering judgment Consequences Repair costs to Colorado DOT Number of days highway closed Length of detour required Lost wages and truck revenues Risk Value (Utah DOT) Read the entire page →
From page 71... ... MEASURING AND MANAGING TRANSPORTATION SYSTEM RESILIENCE 71 Output Measures Intermediate Measures Input Data Vulnerability (San Diego International Airport) Exposure Annual number of days of extreme heat Area exposed to flooding 95th percentile risk of sea level rise Consequences Asset damage Service disruption Job loss Life safety consequences Bird habitat damage Resilience Indicators (LACMTA) Read the entire page →
From page 72... ... 72 INVESTING IN TRANSPORTATION RESILIENCE Output Measures Intermediate Measures Input Data Net Benefits of Resilience Improvements (Colorado DOT) Annual risk without improvement Annual risk with improvement Costs of improvements Net Benefits of Resilience Improvements (Utah DOT) Read the entire page →
From page 73... ... MEASURING AND MANAGING TRANSPORTATION SYSTEM RESILIENCE 73 subsequent studies of mitigation actions. They conduct assessments of consequences to gain an understanding of the impacts of failing to act in the face of climate change. Read the entire page →

From page 45...

... 45 Transportation agencies across the modes have taken different steps to integrate resilience analysis into their decision-making processes. Some agencies have developed comprehensive quantitative analysis procedures to estimate both the current level of resilience and the relative benefits and costs of candidate investments to improve resilience.