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Integrating Climate Change into the Transportation Planning Process

Chapter 2: Opportunities for Linking Transportation Planning and Climate Change

State DOTs and MPOs nationwide use common methods in transportation planning. Most long range transportation planning efforts follow a sequence of several steps to arrive at a plan. At each step certain information is incorporated and decisions are made. While these typical practices may not be explicitly mentioned in federal planning statues and regulations, they are conventional applications that are common across regional and state boundaries. Within these conventions, there are potential points to integrate considerations of climate change. Although there is no federal mandate to consider climate change in transportation planning, state DOTs and MPOs can go beyond existing statutes to integrate climate change at these specific points.

At the same time, federal planning legislation plays an important role in transportation planning processes. DOTs and MPOs are required to meet certain minimum standards in their LRTPs. Federal regulation establishes planning timelines, factors to consider, and parties to consult. While future legislation may explicitly mention climate change and GHG emissions, existing legislation is already relevant to climate change. Both legislators and planners should be aware of how federal regulations can enable consideration of climate change in long range transportation planning.

2.1. Review of the Long-Range Transportation Planning Process

Transportation plans can consider both mitigation of and adaptation to climate change. Mitigation of climate change means reducing the major cause of climate change: GHG emissions released by human activities. Adaptation to climate change means minimizing the potential impacts on the transportation system from climatic changes such as rising average temperatures, increased intensity of storms, rising sea levels, and increases in overall climatic variability.

Opportunities for practitioners to address climate change exist within several key elements of transportation plans. Each of these elements can incorporate climate change directly, by explicitly addressing climate change, and indirectly, by addressing elements of transportation that are linked to climate change. Components within both statewide and metropolitan transportation plans that can include climate change are:

In addition to the basic components of planning documents, transportation agencies can also incorporate climate change through their long term planning processes. The stakeholders involved, the information considered, and the decision-making structure at each step of transportation planning influence the eventual outcome of the plan. Opportunities to incorporate climate change throughout the transportation planning process include:

The figure below illustrates the basic steps in the long range transportation planning process of state DOTs and MPOs in relation to the above opportunities to integrate climate change. The steps are organized to reflect the typical metropolitan transportation planning process. Most MPOs will go through each of these steps in drafting their transportation plans, although the order of steps may vary slightly. In addition, state DOTs use many of the same steps in drafting statewide transportation plans. The steps can also apply to the drafting of corridor plans, an increasingly important function of MPOs. The paragraphs following the figure explain the steps and their relation to climate change in more detail.

Figure 1: Opportunities to Integrate Climate Change in Long Range Transportation Planning
This diagram describes the typical long range transportation planning process in terms of steps, components, and processes. In the center of the diagram is a series of six basic steps, with arrows leading from step to step. Step 1 is Stakeholder Identification and Initial Outreach. Step 2 is Establish Vision, Goals, and Objectives. Step 3 is Define Performance Criteria and Data Needs. A feedback loop connects Step 3 back to Step 2, indicating that Step 2 may be repeated or refined in the course of carrying out Step 3. Step 4 is Evaluate Deficiencies. Step 5 is Develop Alternative Plan Scenarios. Step 6 is Evaluate Alternatives & Select Preferred Alternative. A feedback loop connects Step 6 to Step 5. A larger feedback loop also connects Step 6 to Step 1, indicating that any earlier step may be repeated or refined at any point in the process. Above these six steps are key processes in long range transportation planning that can incorporate climate change. Processes of coordination and stakeholder outreach span all six steps in the process. The process of integrating land use planning can begin in Step 2 and continue through Step 6. The process of linking funding mechanisms to climate change considerations can occur especially at Steps 3, 5, and 6. Below the series of six steps are the key components of long range transportation plans, represented in the order they are typically developed. At Step 2, the vision, goals, and trends are developed. At Step 3, performance measures are developed. At Step 4, trends and challenges are developed. At Step 5, strategies and improvement projects are developed. At Step 6, performance measures may be further developed.

At Step 1: Stakeholder Identification and Initial Outreach, transportation agencies typically identify partners and stakeholders to participate in the process. They also establish and publicize a framework for the planning process. Although outreach and coordination continues throughout the planning process, this is a key point for its initiation. Transportation agencies can actively engage environmental and state and local government agencies and other organizations involved in climate action planning. Private industries with a large impact on transportation GHG emissions, such as those with large vehicle fleets, can also be contacted.

At Step 2: Establish Vision, Goals, and Objectives, agencies establish a vision and related goals and objectives for the transportation system. The vision reflects an overall desired end state for the system, while goals and objectives address individual aspects of the system such as mobility, safety, preservation, and environmental performance. The vision can emphasize mitigating the system's impact on climate change and consider preservation of the system in the face of shifts in climate. Goals can address specific linkages between transportation and climate change such as VMT per capita, total energy use, and total GHG emissions. Connections between transportation and land use can be formally considered beginning with this step.

In Step 3: Define Performance Criteria and Data Needs, agencies develop criteria that will measure progress towards stated objectives. They also identify data that will be needed to measure performance against the criteria. Agencies can include performance measures related to GHG emissions and adaptation to climate change. The selection of appropriate performance measures at this step can help prioritize funding for projects that mitigate or adapt to climate change at later stages of the process.

In Step 4: Evaluate Deficiencies, agencies characterize the existing system relative to performance criteria, gather input from stakeholders and the public on priority deficiencies, and forecast future deficiencies. At this stage agencies can incorporate climate change into the assessment of trends and challenges. Specifically, agencies can recognize and assess the threat posed by GHG emissions and climate change and forecast vulnerability of the transportation system to climate change. This step might involve screening existing transportation infrastructure and proposed projects to determine their potential vulnerability to the impacts of climate change. Once this screening step is complete, it may be necessary to conduct detailed vulnerability assessments that incorporate localized projections of climate change impacts and the associated effects on the system. Additionally, adaptation also may be an important criterion both for determining the form of the system and prioritization of projects.

At Step 5: Develop Alternative Plan Scenarios, agencies develop various approaches for achieving the stated objectives and distill several diverse, manageable alternatives. Agencies typically identify fiscal constraints and opportunities at this stage as well. This step can identify alternatives that facilitate mitigation of GHG emissions or adaptation to climate change. Specific strategies and improvement projects can be included in the alternatives developed.

In Step 6: Evaluate Alternatives and Select Preferred Alternative, agencies apply performance criteria to alternative scenarios and select the alternative that best meets community goals. This stage includes the preparation of a tiered project list based on the selected scenario. At this step, agencies can apply climate change related performance criteria to the alternatives developed. Agencies can examine the impacts of proposed mitigation and adaptation strategies to ensure that the selected alternative appropriately addresses climate change. It is important to note that decisions often include tradeoffs among community goals. For example, maximizing highway mobility may increase GHG emissions.

2.2. Relationship of Federal Planning Statutes and Regulations

Several federal statutes and regulations govern the transportation planning process. The text of these documents provides some opportunities to link climate change considerations with the planning process. Specifically, federal planning regulations include:

These documents set out the requirements for undertaking transportation planning, and include statements regarding the scope of planning processes, required procedures, and required content for metropolitan and statewide transportation planning under both FHWA and FTA. While there are no specific requirements to directly address climate change, recent revisions to legislation have further incorporated energy and environmental considerations. These revisions offer greater opportunities for MPOs and state DOTs to integrate climate change considerations within their planning processes. For example, 23 USC 143(a) states that it is in the national interest to:

...encourage and promote the safe and efficient management, operation, and development of surface transportation systems that will serve the mobility needs of people and freight and foster economic growth and development within and between States and urbanized areas, while minimizing transportation-related fuel consumption and air pollution through metropolitan and statewide transportation planning processes...

The goal of minimizing fuel consumption and air pollution can be interpreted as a direct link to climate change and justification for metropolitan transportation planning to consider climate change mitigation strategies. Section 23 USC 135(a) mandates similar consideration of fuel-consumption and air pollution in statewide planning. Additionally, requirements for the examination of the effects of transportation decisions on the environment and energy consumption are reiterated throughout the planning legislation. Energy and environment are one of the eight required planning factors.

The planning regulations also include a number of requirements that generally align with climate change mitigation and adaptation. For example, provisions that relate to efficient management and operation of the transportation system, coordination with land use plans, and congestion mitigation can all related to reducing GHG emissions. For adaptation, the requirements for infrastructure preservation and maintenance, as well as corridor preservation and connectivity of the system, can provide direct avenues for consideration of adaptation strategies in planning.

Types of Linkage Opportunities

There are four general types of climate change linkage opportunities in planning statutes and regulations:

  1. Requirements to address energy and environmental concerns - These sections provide a link to GHG mitigation, since GHG emissions from transportation are largely correlated with energy consumption and impacts of climate change are important considerations in environmental protection. (23 CFR 450 Subparts 200, 206, 214, and 306)
  2. Requirements to ensure an integrated transportation system, preserve the projected and existing system, and ensure the safety and security of the system for users - These sections could be interpreted as requiring or encouraging adaptation strategies, since MPOs and state DOTs will need to consider the implications of climate change (such as sea level rise and accelerated aging from temperature swings) on their infrastructure to ensure effective connectivity is preserved. (23 CFR 450 Subparts 206, 214, and 306; 49 CFR 613 Subparts 100 and 200)
  3. Transportation demand management and transportation system management strategies - Many sections of the federal requirements contain language that encourages these strategies. Both can be considered climate change mitigation strategies, if they reduce congestion or reduce vehicle travel. Similarly, transit enhancements and emphasis on non-motorized (pedestrian and bicycle) transportation can potentially serve as climate change mitigation strategies. (23 CFR 450 Subparts 200 and 320)
  4. Consultation requirements - These requirements could be interpreted as requiring that transportation planning processes consider climate action planning activities going on at the state or regional level, local government plans or policies that may consider climate change, and the work of environmental agencies as it relates to climate change and GHG emissions. (23 CFR Subpart 208 and 214)

Federal Planning Factors

Federal statutes require MPOs and state DOTs to consider eight factors in their planning functions. These factors serve as de facto goals for transportation planning and include topic areas of economic vitality, safety, security, mobility, environment, connectivity, efficiency, and preservation. While climate change is most directly related to the environment and energy conservation planning factor (factor 5), it is related to each of the eight factors, if indirectly, as illustrated in Table 1.

Table 1: Applicability of Federal Planning Factors to Climate Change (23 CFR 450.206(a) and 450.306(a))
Planning Factor Applicability of Climate Change Considerations
(1) support the economic vitality of the [United States, the States, nonmetropolitan areas, and] metropolitan area[s], especially by enabling global competitiveness, productivity, and efficiency; In addition to a physical threat, climate change also poses an economic threat. Climatic changes can damage natural environmental assets as well as manmade assets. Weather-related natural disasters can cause damage worth billions of dollars. These losses have a direct toll on local, regional, and national economies. At the same time, the development of new technology to reduce and prepare for climate change offers economic development opportunities. New transportation technologies can generate new economic activity as they are developed and exported.
(2) increase the safety of the transportation system for motorized and nonmotorized users; A safe transportation system protects users from hazards, including hazards resulting from climate-related stresses on the system. Transportation agencies need to protect the system from potential floods and perform routine maintenance and replacement on infrastructure components affected by extreme temperatures and storms. Other safety enhancements can actually reduce GHG emissions. Enhancements that reduce the risk of crashes and smooth traffic flow reduce GHG emissions from congestion. In some cases, slowing vehicle travel speeds can contribute to improved fuel efficiency and improved safety.
(3) increase the security of the transportation system for motorized and nonmotorized users; A secure transportation system ensures the protection of critical infrastructure and exposes users to less risk. Infrastructure protection is going to require assessing risk from climate-related stresses on the system. Transportation agencies need to consider security as part of a broader consideration that incorporates planning for natural disasters, emergency response and preparedness and infrastructure preservation.
(4) increase the accessibility and mobility of people and freight; While accessibility and mobility have often been interpreted as synonymous with more travel by car and truck, these goals can also be achieved with reduced vehicle travel. Multimodal transportation systems can be coordinated with land use patterns such that people and goods need to travel shorter distances and make fewer trips by car and truck. In fact, travel by private car is inherently inaccessible for many low-income, elderly, and young people. The systematic provision of other options both improves mobility for these populations and helps to reduce GHG emissions.
(5) protect and enhance the environment, promote energy conservation, improve the quality of life, and promote consistency between transportation improvements and State and local planned growth and economic development patterns Mitigating climate change is essential in order to protect the environment from long term shifts in weather patterns. Reducing GHG emissions is virtually equivalent to conserving energy, since most GHG emissions come from the burning of fossil fuels. One of the chief ways that transportation agencies can reduce GHG emissions is to reduce the total amount of on-road travel. When transportation improvements are coordinated with planned growth patterns, the need to travel (and especially the need to travel by car) can be reduced.
(6) enhance the integration and connectivity of the transportation system, across and between modes [throughout the State], for people and freight; One of the chief ways that transportation agencies can reduce GHG emissions is to reduce the total amount of on-road travel. Shifting passenger trips from cars to public transportation, biking, and walking, and freight trips from trucks to rail (and possibly ships) can help to reduce on-road travel. To the extent that agencies can provide more modal choices and improve the ease of transfers between modes, passengers and shippers are more likely to choose an alternative mode for at least part of each trip.
(7) promote efficient system management and operation The energy efficiency of the transportation system depends in part on the efficient operation of the system. Travel times can be improved and congestion reduced in many cases through better incident management, real-time information distribution, and traffic flow engineering. Reduced congestion translates to improved fuel efficiency and reduced GHG emissions.
(8) emphasize the preservation of the existing transportation system The transportation system, like other assets of our built environment, is threatened by climate change. Adaptive responses to increased heat, rising sea levels, and higher incidences of flooding must be considered in order to preserve the system.

Other Federal Regulations

In addition to federal requirements that directly address the transportation planning process, air quality and climate change issues are becoming more prevalent in the transportation planning process through other avenues. For example, a new requirement in the Energy Bill, Section 55601(f), encourages state and local governments to include short sea shipping and other marine transportation solutions in their transportation planning process as a means to reduce transportation-related energy consumption:

§55601. Short sea transportation program

(f) Multistate, State and Regional Transportation Planning - The Secretary, in consultation with Federal entities and State and local governments, shall develop strategies to encourage the use of short sea transportation for transportation of passengers and cargo. The Secretary shall–

  1. (1) assess the extent to which States and local governments include short sea transportation and other marine transportation solutions in their transportation planning;
  2. (2) encourage State departments of transportation to develop strategies, where appropriate, to incorporate short sea transportation, ferries, and other marine transportation solutions for regional and interstate transport of freight and passengers in their transportation planning; and
  3. (3) encourage groups of States and multi-State transportation entities to determine how short sea transportation can address congestion, bottlenecks, and other interstate transportation challenges.

Similarly, SAFETEA-LU Section 6001 requires consultation and environmental mitigation strategies to be incorporated early into the transportation decision making process. This requirement presents an opportunity for considering climate change mitigation strategies. Mitigation strategies could include, for example, short sea shipping strategies, thereby also fulfilling the Section 55601(f) requirements.

Specific Linkage Opportunities

Appendix B presents specific opportunities to link existing federal transportation planning requirements to climate change mitigation and adaptation. The table in Appendix B lists the relevant sections of legislation, the aspect of planning that the section addresses, excerpted relevant language from the legislation, and the potential ties to climate change considerations. Since this table breaks down the legislation comprehensively section by section, and the language within the legislation is often repetitive between sections, the table intentionally reiterates similar opportunities for integration of climate change considerations by both MPOs and state DOTs. Within the table, we identify opportunities for direct and indirect linkages to existing language and opportunities to add new language to the legislation to create linkages.

Updated: 12/23/2016
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