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Once transportation vulnerabilities are identified, a logical next step is to consider how to address them. Integrating results of the vulnerability assessment into decision making is important to ensure that study results are used in practice. While the information developed from the vulnerability assessment should be used to satisfy the study objectives, the results may also be useful in ways not initially anticipated. This section includes strategies to effectively incorporate vulnerability assessment findings into practice.
While we include several in practice examples in this section, the FHWA's initial round of vulnerability assessment pilot projects was for the most part limited to the vulnerability assessment itself. The FHWA will sponsor a second round of pilots with a goal of helping further the State of the practice in applying vulnerability assessment results into decision making.
Transportation agencies may choose to focus their efforts on those assets identified in the vulnerability assessment as having high likelihood of climate impact and high consequence. For these assets, detailed analysis of the costs and benefits of adaptation strategies could be conducted. Strategies might include engineering new assets to withstand environmental conditions anticipated in the future (e.g., construction materials better suited to higher heat days), retrofitting existing assets (e.g., adding barriers to prevent water incursion into tunnels), more intensive maintenance schedules (e.g., more frequent cleaning of drains), systems planning (e.g., siting new facilities outside of expanded flood plains), and improved operations plans for weather emergencies. Adaptation strategies should be evaluated based on cost savings from avoided impacts as well as implementation costs. Strategies should also be evaluated based on their feasibility, efficacy, ability to withstand a range of climate hazards, and co-benefits.
Not many agencies have conducted these analyses to date. As such, the FHWA anticipates making this section of the framework more robust based on experience with the second round of pilots.
Incorporating vulnerability assessment results into existing and updated processes can be an effective mechanism to implement lessons learned quickly and comprehensively. Use of the vulnerability assessment results in this way can be seen as improving existing analysis and practice, rather than as a separate and distinct activity. Considering climate change as one of many risks to be considered in transportation decision-making rather than as a separate issue lowers barriers to adaptation. Agencies may be able to incorporate climate change vulnerability assessment results into:
The asset management process is a natural fit for incorporating climate change and extreme weather vulnerability information. In many cases, existing infrastructure may not be up to handling climate change and extreme weather events. Consideration of resilience, replacement, and restoration of assets can be integrated into asset management programs. Work on a vulnerability assessment can serve as a launch point to begin looking at a State's asset management system from the standpoint of climate resilience.
State DOTs and MPOs have a strong interest in integrating climate change adaptation, hazard mitigation, and transportation planning into a holistic planning process. In many communities, hazard mitigation occurs separately from local planning processes, including transportation planning. This practice can sometimes result in land use and transportation planning that inadvertently encourages development in hazardous areas.
One of the assets evaluated was the San Francisco-Oakland Bay Bridge touchdown and toll plaza on the Oakland side. The asset is protected by a combination of engineered shoreline protection and wetlands. Even so, the shoreline protection would be overtopped under the mid and late century sea level rise plus 100-year storm scenarios. This would inundate the bridge touchdown and toll plaza as well as other transportation assets in the area (Interstate 80, West Grand Avenue, Mandela Parkway, Burma Road, 7th Street Highway and Railroad Pumps, and Union Pacific Martinez subdivision).
For asset-specific adaptation measures for midcentury, the team considered improved drainage, retrofit, and raised road surface. Improved drainage around the freeway and toll plaza would mean that when inundation occurs, there might be only partial closure of the roadway and, after a storm/high tide event, water would drain off the road surface quickly enough to minimize disruption. Retrofitting to better withstand temporary inundation would include placing wiring and electronics for the toll plaza above the flood elevation and waterproofing buildings and toll booths. Raising the road surface in areas identified as particularly vulnerable could be done as part of regularly scheduled maintenance. For end-of-century, more expensive measures may warrant consideration such as elevating the entire freeway above the end-of-century 100-year storm level. This might also provide benefits to the region because the raised road could serve as a levee protecting West Oakland.
The team also considered regional adaptation measures for midcentury-creating a berm, supporting wetland growth, and constructing a floodwall. For end-of-century the team considered constructing levees, raising a floodwall built at midcentury, and building new wetlands (It is unlikely that wetlands will be able to keep pace with sea level rise at the end of the century).
FHWA Adaptation Peer Exchanges Final Report, FHWA, August 2012. This report synthesizes key themes and lessons from a series of three FHWA-sponsored peer exchanges on climate change adaptation, including examples of effective implementation practices presented by the MPO and State DOT participants.
Flooded Bus Barns and Buckled Rails: Public Transportation and Climate Change Adaptation, FTA, 2011. This comprehensive FTA report on climate change adaptation for public transit includes a chapter on implementation of climate change adaptation strategies at transportation agencies. There is also a case study on Transport for London's experience with asset management.
Eligibility of Activities to Adapt To Climate Change and Extreme Weather Events Under the Federal-Aid and Federal Lands Highway Program, FHWA, 2012. This memo clarifies that Federal-aid and Federal Lands highway funding may be used for climate change adaptation work. The memo notes that creating
a more resilient transportation system is a priority for the FHWA and provides some examples of eligible uses of Federal-aid and Federal Lands highway funds to consider the potential impacts of climate change and extreme weather events and apply adaptation strategies.
It is difficult to overstate the importance of public stakeholder engagement in vulnerability assessment and adaptation planning. If the target audience does not buy into the vulnerability assessment, it may not support the resulting adaptation actions. The appropriate method of engaging stakeholders will vary according to the agency, context, and objectives. It is very important to plan for a specific target audience, and agencies often engage different groups of stakeholders in stages.
Successful engagement of internal staff requires listening and incorporating their feedback and perspective. If these staff members are engaged and feel that they can take ownership over the strategy, they may be more willing to provide valuable leadership and insight.
Communicating the need for climate change adaptation is challenging for several reasons. First, people often assume that "climate change" issues refer exclusively to mitigation. Organizations and government agencies often house climate change adaptation efforts within traditional environmental programs, even though adaptation impacts multiple programs, including asset management, risk mitigation, operations, and planning. Second, the term climate change has become politicized, inhibiting public agency communication and action in those jurisdictions where political forces do not wish to address the issue. Lastly, it is difficult to communicate the range of uncertainty associated with climate projections. For example, agencies are often concerned about releasing detailed inundation maps, which might alarm and alienate coastal property owners because it is difficult to describe the specific assumptions and uncertainties associated with these maps. Almost any adaptation assessment effort will show increased vulnerability to flooding for coastal properties, but acknowledging potential additional flooding vulnerability decreases the economic value of the property.
The 2010 pilots and participants in the FHWA sponsored peer exchanges have identified several strategies for effectively communicating climate change vulnerability: