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Integrating Climate Change into the Transportation Planning Process

Chapter 3: Overview of Current Practice

A number of state DOTs and MPOs are already integrating climate change into planning documents and processes through the opportunities described above, and through other means. Practices are evolving rapidly. The experiences of these transportation agencies can inform other DOTs and MPOs as well as contribute to broader discussions on how best to integrate climate change into long range transportation planning.

3.1. Summary of Climate Change Integration Activities

Within long-range transportation plans, climate change appears in a number of places. The simplest way for a plan to incorporate climate change is to acknowledge its connection to transportation, often in a section on trends and challenges. Many plans also now include mitigation of GHG emissions in a hierarchical policy structure (Vision - Goals - Policies - Strategies). The position of climate change within the structure varies from plan to plan. Some plans include an individual goal related to climate change. Others include policies or strategies related to climate change mitigation under one or several goals. Finally, a few plans incorporate performance measures based on GHG emissions.

The integration of climate change into long-range transportation plans is a new development. Plans adopted within the last year or two are much more likely to incorporate climate change than plans adopted a few years ago. Many DOTs and MPOs are working on plans or concepts related to climate change that have not yet been fully incorporated into LRTPs.

Quantification of GHG emissions will likely be a key component of transportation planning in the future. In order to effectively reduce GHG emissions, planners need to know current and future emissions levels and the potential impacts of various policies and strategies on emissions. While only New York State currently requires quantification of GHG emissions from plans or transportation improvement programs (TIPs), several other states are considering such a requirement. Likewise, only a handful of MPOs have conducted analyses of GHG emissions, but more are considering or planning to conduct such analyses. Agencies face a number of questions about appropriate tools, methodologies, and data.

As expected, larger MPOs are typically doing more than smaller MPOs with regard to climate change. In addition to the obvious differences in staff sizes and resources, the variation in autonomy and regional planning powers that MPOs have also plays a role. Some larger MPOs serve as independent regional planning agencies, with influence (though not necessarily jurisdiction) over land use, economic development, natural resources, and community development. These functions allow for integrated planning, which can be much more effective at reducing GHG emissions from transportation than the traditional transportation planning process alone. The needs and concerns of small MPOs in relation to climate change are substantially different than those of large MPOs, and merit special attention.

A few GHG mitigation strategies are emerging as particularly popular among transportation agencies. Many agencies cite integrated transportation and land use planning as the most promising long term strategy for reducing transportation GHG emissions. In the shorter term, pricing strategies and promotion of alternative modes are also priorities for many agencies. Meanwhile, LRTPs often do not explicitly recognize the effect that existing policies and strategies can have to reduce transportation GHG emissions. For example, transportation demand management policies to reduce congestion and air pollution can also reduce GHG emissions.

Mitigating responses to climate change are much better developed than adaptive responses. Some agencies are beginning to develop very specific strategies to analyze and reduce GHG emissions. At this point, adaptive responses in plans are typically just acknowledgements of risk or suggestions for research. At least one transportation agency, the San Francisco Bay Area's Metropolitan Transportation Commission, is conducting a research study on the topic.

Many DOTs and MPOs are working across institutional boundaries on climate change issues. DOTs and MPOs are both leading and participating in multi-agency climate change groups focused on developing action plans, tools, and guidance documents for climate change mitigation and adaptation. Some DOTs and MPOs are also addressing climate change through existing interagency groups. Climate change issues span boundaries of geography and jurisdiction. Many agencies recognize that multi-agency action has the greatest potential to incorporate climate change into transportation planning.

By the same token, some transportation agencies are deferring individual action on climate change in expectation of direction from multi-agency groups or from higher levels of government. There is considerable uncertainty about how climate change regulation at both the federal and state levels will impact transportation planning requirements. Many agencies are eager to receive appropriate guidance before taking steps on their own.

3.2. Influence of State Climate Change Regulatory Action

Many of the DOTs and MPOs that have been most proactive in the area of climate change are in fact driven by state legislation on GHG emissions. California in particular is developing a strong administrative and regulatory framework to reduce GHG emissions in response to AB32. The California Department of Transportation (Caltrans) and the state's large MPOs are moving rapidly to adapt to expected future mandates.

In California, Assembly Bill (AB) 32 (the Global Warming Solutions Act of 2006) drives much of the activity around climate change mitigation. The law mandates that California reduce GHG emissions to 1990 levels by 2020. The transportation sector, as a large contributor to GHG emissions, is expected to produce significant reductions. Proposed legislation (SB 375) would require the California Air Resources Board (CARB) to set emission reduction targets for the transportation sector and allocate those reduction targets to MPOs. If enacted, this legislation would directly affect the long-range planning functions of MPOs in the state.

While Congress was clear that it was not extending NEPA requirements to transportation plans and programs (23 CFR Appendix A to Part 450), recent legal and legislative action at the local level suggests that transportation agencies will also have to consider GHG emissions under the California Environmental Quality Act (CEQA). In 2007, the state Attorney General began warning MPOs that they could be required to analyze the GHG impacts of their regional transportation plans under CEQA. Even though no official guidance exists on how such analyses should be conducted, or how significance of impacts should be determined, some MPOs have begun exploring GHG impacts in their CEQA documents.

In addition, the California Transportation Commission (CTC) recently proposed revisions to California's RTP Guidelines that incorporate climate change into the regional transportation planning process. The new guidelines suggest specific policies, strategies, and performance measures for regional smart growth. They suggest modeling and analysis techniques for transportation GHG emissions. They also promote technical assistance by Caltrans and the CTC to regional transportation planning agencies for GHG modeling.

Washington State is also instituting regulations that will affect transportation planning. In March 2008, Washington Governor Gregoire signed climate change framework legislation HB 2815, which includes a requirement to reduce light duty vehicle per capita VMT 18% by 2020, 30% by 2035, and 50% by 2050. Washington has formed a Climate Action Team (CAT), which includes Washington's Transportation Secretary. The CAT is being advised by sector-specific Implementation Working Groups, charged with developing the specific implementation steps needed to achieve the reductions in the climate plan. A WSDOT representative co-chairs the Transportation Implementation Working Group. The group is currently developing recommendations for specific actions that can help achieve the VMT reduction goals laid out in HB 2815. It is likely that implementation steps will eventually result in new requirements on LRTPs in Washington.

In New York State, the State Energy Plan, adopted in 2002, is one of the first in the nation to integrate transportation planning, energy conservation, greenhouse gas mitigation, and air quality planning. One of the recommendations in the State Energy Plan is that MPOs, in conjunction with the State, assess the energy use and greenhouse gas emissions expected to result from implementation of transportation plans and programs. In response, NYSDOT has drafted methodological guidance to help MPOs fulfill this recommendation. All 13 MPOs in New York have now estimated energy use and CO2 emissions from their LRTPs and also from their transportation improvement programs (TIPs).

Updated: 12/23/2016
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