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From page 18... ... 18 Chapter 2: LITERATURE REVIEW AND RESILIENCE DEFINITION Introduction This literature review examined four major topical areas. The next section examines alternative definitions of resilience as offered by a range of disciplines. Read the entire page →
From page 19... ... 19 Figure 2: Perspectives on Resilience Will Vary by Where You Sit at the Table • "The ability to prepare for and adapt to changing conditions and withstand and recover rapidly from disruptions. Resilience includes the ability to withstand and recover from deliberate attacks, accidents, or naturally occurring threats or incidents" (Office of the President 2009) Read the entire page →
From page 20... ... 20 voluminous and dispersed throughout the TRB modal and subject area domains. As of January, 2019, for example, 219 security-, emergency management-, and infrastructure protection-related planning and implementation projects had been initiated through TRB programs. Read the entire page →
From page 21... ... 21 For purposes of this project, the working definition of resilience offered by The National Academies was adopted: The ability to prepare and plan for, absorb, recover from, or more successfully adapt to adverse events (The National Academies 2012) This definition contains some key phrases that are inherent to a good approach leading to a more resilient transportation system. Read the entire page →
From page 22... ... 22 Locks and Dams 52 and 53 The approximate $3 billion Olmsted Locks and Dam project to replace the Locks and Dams 52 and 53, completed in 2018, was the US Army Corps of Engineers' (USACE) largest civil works project since the construction of the Panama Canal. Read the entire page →
From page 23... ... 23 • The ability to maintain or restore normal traffic operations under a range of conditions; and • The ability to maintain or restore mission-critical business processes. The state-of-the-practice in transportation system resilience varies considerably across the nation. Read the entire page →
From page 24... ... 24 Each domain represents important capabilities contributing to the operational resilience of an organization. More specifically, each domain is composed of a purpose statement, a set of specific goals and associated practice questions unique to the domain and a standard set of Maturity Indicator Level (MIL) Read the entire page →
From page 25... ... 25 "leadership is necessary." One area where transportation agencies have shown leadership among public agencies is in the application of CMMs to enhance aspects of their agency performance. Before discussing examples of CMMs and their application to transportation contexts, it is useful to transition to this discussion with a summary of the key concepts in organization theory and from the literature on organizational change that serve as the foundation for a CMM approach to state DOT self-assessment for resilience. Read the entire page →
From page 26... ... 26 Maturation – changing the level of maturity of collaborative planning by using strategies targeted at specific influence factors. For example, establishing formal institutional mechanisms for fostering collaboration is likely an important step in institutionalizing what may have been done on an ad hoc basis previously. Read the entire page →
From page 27... ... 27 Georgia DOT (GDOT) Institutional Response to Serious System Disruptions On January 29, 2014, thousands of cars and trucks were stuck on ice-coated highways in the greater Atlanta area. Read the entire page →
From page 28... ... 28 • Performance measurement including measures definition, data acquisition, and utilization • Culture including technical understanding, leadership, outreach, and program legal authority • Organization and workforce including programmatic status, organizational structure, staff development, and recruitment and retention • Collaboration including relationships with public safety agencies, local governments, MPOs and the private sector Four levels of maturity were defined: Level 1 - Activities and relationships largely ad hoc, informal and champion-driven, substantially outside the mainstream of other DOT activities Level 2 - Basic strategy applications understood; key processes support requirements identified and key technology and core capacities under development, but limited internal accountability and uneven alignment with external partners Level 3 - Standardized strategy applications implemented in priority contexts and managed for performance; TSM&O technical and business processes developed, documented, and integrated into DOT; partnerships aligned Level 4 - TSM&O as full, sustainable core DOT program priority, established on the basis of continuous improvement with top level management status and formal partnerships FHWA Business Process Frameworks for Transportation Operations: In support of an agency's TSM&O efforts, FHWA has developed CMM-based self-assessment frameworks in seven topical areas (FHWA 2020; Scriba et. Read the entire page →
From page 29... ... 29 to each criterion in the 31 questions. They can then see how the overall program effectiveness matches to others or how it changes over time. Read the entire page →
From page 30... ... 30 • Place greater emphasis on a reliable and efficient transportation system as a planning goal • Begin the process of putting in place safeguards to protect the transportation system and its users given projected future weather conditions • Emphasize the importance of physical network connections (cascading effects, dependencies, etc.) in determining transportation needs • Emphasize institutional partnerships and collaboration • Promote the consideration of the broader implications of transportation system resilience to other policy areas • Provide evidence for local government bonding requirements that infrastructure risk has been considered as part of the "due process" requirement • Help satisfy Federal requirements (ARC 2018) Read the entire page →
From page 31... ... 31 With respect to transportation agencies, NCHRP 20-05 Topic 48-13 noted that a broader systems perspective on resilience is required due to three primary barriers to incorporating resilience into state DOTs' management practices: • Lack of understanding of how resilience is related to risk assessment • Lack of metrics to measure system resilience and the benefits expected from resilience investments • Lack of clear direction as to how system resilience can affect mandated transportation performance measures such as safety, infrastructure health, system operations, and vice versa (Flannery et. Read the entire page →
From page 32... ... 32 DISRUPTION IMPACTS AND SYSTEM ADAPTATION The literature on disruptions and on strategies to adapt to such disruptions is vast and diverse, with the range in literature reflecting the type of disruption being considered and the context of the disruption itself. The following discussion summarizes some of the key contributions of this literature as they relate to understanding better the actions that can be taken to enhance transportation system resilience. Read the entire page →
From page 33... ... 33 • Low – disruptive events that can affect regional or local transportation and rank low to moderate on economic loss incurred, and/or due to injuries incurred. Events such as the bridge closure on a major highway fall in this category. Read the entire page →
From page 34... ... 34 Improving the Resilience of Transit Systems Threatened by Natural Disasters: This report compiled into one table the potential impacts to public transit infrastructure and services of different natural disasters, threats, and hazards. Table does not group these impacts into larger categories. Read the entire page →
From page 35... ... 35 Table 1: Summary Table of Climate Impacts on Highway System Climatic/ Weather Change Impact to Infrastructure Impact to Operations/ Maintenance Temperature Change in extreme maximum temperature • Premature deterioration of infrastructure; • Damage to roads from buckling and rutting; • Bridges subject to extra stresses through thermal expansion and increased movement. • Safety concerns for highway workers limiting construction activities; • Thermal expansion of bridge joints, adversely affecting bridge operations and increasing maintenance costs; • Vehicle overheating and increased risk of tire bow-outs; • Rising transportation costs (increase need for refrigeration) Read the entire page →
From page 36... ... 36 Climatic/ Weather Change Impact to Infrastructure Impact to Operations/ Maintenance Precipitation Greater changes in precipitation levels • If more precipitation falls as rain rather than snow in winter and spring, there will be an increased risk of landslides, slope failures, and floods from the runoff, causing road washouts and closures as well as the need for road repair and reconstruction; • Increasing precipitation could lead to soil moisture levels becoming too high (structural integrity of roads, bridges, and tunnels could be compromised leading to accelerated deterioration) ; • Less rain available to dilute surface salt may cause steel reinforcing in concrete structures to corrode; • Road embankments at risk of subsidence/heave. Read the entire page →
From page 37... ... 37 Climatic/ Weather Change Impact to Infrastructure Impact to Operations/ Maintenance Sea-level rise Sea-level rise • Higher sea levels and storm surges will erode coastal road base and undermine bridge supports; • Temporary and permanent flooding of roads and tunnels due to rising sea levels; • Encroachment of saltwater leading to accelerated degradation of tunnels (reduced life expectancy, increased maintenance costs and potential for structural failure during extreme events) ; • Loss of coastal wetlands and barrier islands will lead to further coastal erosion due to the loss of natural protection from wave action. Read the entire page →
From page 38... ... 38 Table 2: Categories of Public Transit Infrastructure and Services Impacts Category of Impacts Public Transit Infrastructure and Services Impacts Electrical & Power Damage  Power failures  Power failures due to tree and debris damage  Power failures due to flooding of substations  Power failure/damaged electrical infrastructure from accumulating snow/ice, brown outs  Overheated electrical equipment  Sagging and/or failure of catenary systems  Auxiliary system failures at stations and on buses/trains due to increased use of air conditioning  Lightning strike damage to catenary lines, circuitry and switching systems • Damaged electrical transmission, signal systems and other circuitry associated with surface and subterranean facilities Asphalt Damage • Asphalt buckling • Asphalt heaving/potholes from freeze-thaw • Urban/street and riverine flooding from snow melt • Ground and embankment failure resulting in rail/pavement damage Rail Damage • Rail buckling • Rail fracturing • Gradual degradation of tracks/rail beds from increased freeze-thaw • Frozen rail switches • Track and tunnel misalignments • Ground and embankment failure resulting in rail/pavement damage Bridge Damage • Binding/locking of moveable bridges • Ice jams impacting bridges • Wind induced bridge vibrations/damage • Bridge pier and abutment scouring • Seismic damage to bridges Other Damage • Damage to signage and other overhead structures • Damage or replacement to bus shelters • Damage to stations and buildings (fixed facilities) • Damage to docks, levees, channels and dams necessary to maintain water-borne transit • Damage to fixed facilities located in the path of fire • Damage to fixed facilities such as stations (surface and subterranean) Read the entire page →
From page 39... ... 39 • Landslides, washouts, land subsidence and erosion along/adjacent to infrastructure • Erosion along/adjacent to infrastructure and bank destabilization • Failure of overwhelmed drainage systems • Damage from salt water intrusion to low-lying coastal infrastructure • Higher water tables and permanently flooded infrastructure is rendered inoperable • Flooding of waterside ferry terminals, docks and piers on a recurring basis • Infrastructure previously unaffected becomes vulnerable due to changing flood zones and exposure to salt water, tidal flooding and storm surge • Vegetation loss impacting erosion control and maintenance Information Systems Disruption • Disruption of passenger information systems Vehicle Damage • Vehicle overheating and excess wear and tear on vehicle components, such as air conditioning and tires • Frozen air lines on locomotives and gelling of diesel engine fuel • More rapid degradation of batteries utilized by rail and buses • Vehicle damage from blowing debris • Train derailment and overturned rail cars during event Impeded Travel • Slow travel orders due to equipment stress (vehicles, tracks, catenary) • Slow travel orders for vehicles operating under high wind conditions • Slow travel orders or annulments of service • Increase in rock falls from freeze-thaw • Freezing of waterways navigated by ferries • Restrictions on ferry operations • Reduction in bridge clearance on waterways • Delays due to snow/ice removal operations • Potential debris on tracks and across navigable waterways • Decrease in water levels restricting use of navigable waterways Direct Impacts to DOT Organization and Operations • Worker/customer health and safety concerns • Cessation of operations until flooding subsides and damage is repaired • Diminished visibility that impedes operations • Risks to employee/customer safety due to slippery walkways/platforms • Rerouting to undamaged areas • Widespread impacts resulting in extensive assessment and repair time • Stranded customers following event • Reduced capacity to implement emergency plans • Potential rerouting or cessation of services until danger has passed Read the entire page →
From page 40... ... 40 • Employee health and safety concerns • Reduced visibility and safety Increased Vulnerability to Other Hazards • Increase in rock falls from freeze-thaw • Landslides, washouts, land subsidence and erosion along/adjacent to infrastructure • Infrastructure previously unaffected becomes vulnerable due to changing flood zones and exposure to salt water, tidal flooding and storm surge • Urban/street and riverine flooding from snow melt • Increase susceptibility to wildfires and the vulnerabilities such an event creates Source: (Matherly et.al. Read the entire page →
From page 41... ... 41 • Risk acceptance, which reflects a knowledgeable determination that a risk is best managed by taking no action at all. The proposed steps for risk assessment included: 1. Read the entire page →
From page 42... ... 42 Disruption Response Metrics – Time to Recovery from Incidents Recovery time and functionality/performance are key elements of measuring infrastructure system resilience and operational resilience. As NIST states, community resilience performance goals are "defined by how quickly the functionality of infrastructure systems recover after a hazard event" (NIST 2016b) Read the entire page →
From page 43... ... 43 Source: (Adams 2012) Figure 4: Resilience Triangle For transportation systems operations, resilience measurement reported in the literature has also focused on this "bouncing back" aspect of resilience with the use of the resilience triangles, recovery times of function or performance, or surrogate metrics to represent recovery performance. Read the entire page →
From page 44... ... 44 impacting Oregon's economy and communities (OSSPAC 2013) Read the entire page →
From page 46... ... 46 Transportation Systems or Network-level Resilience Metrics The degree to which a transportation system provides a reliable trip experience is one of the more important transportation system resilience measures to decision makers. This has been consistently rated highly among transportation system users as an important system performance characteristic. Read the entire page →
From page 47... ... 47 Community Resilience Metrics Community metrics answer the questions: "How resilient is my community? Will my community‘s decisions and investments improve resilience? Read the entire page →
From page 48... ... 48 According to NIST (2016b) , a community's social needs are expected to drive performance goals selected by the community. Read the entire page →
From page 49... ... 49 Examples of effective practices from several U.S. agencies and from one international agency (Transport for London) Read the entire page →

From page 18...

... 18 Chapter 2: LITERATURE REVIEW AND RESILIENCE DEFINITION Introduction This literature review examined four major topical areas. The next section examines alternative definitions of resilience as offered by a range of disciplines.