6.0 Implementation
6.1 Approach to Implementation
6.2 Creating a State Department of Transportation Policy
6.3 Challenges and Solutions
6.1 Approach to Implementation
Each transportation agency will have an established set of policies and procedures for conducting environmental reviews at the project level, consistent with federal and any applicable state regulations and guidelines. Consideration of greenhouse gas (GHG) emissions and climate change effects can be integrated within these policies and procedures.
While these issues could be considered on an ad-hoc basis in every Environmental Impact Statement (EIS) and Environmental Assessment (EA) conducted by the agency, it can be helpful for the agency to establish a written policy and/or guidelines on how GHG emissions and climate change effects will be addressed for different types of projects and different levels of National Environmental Policy Act (NEPA) review, including Categorical Exclusions (CEs) as well as EAs and EISs. Doing so ensures that agency staff know what their charge is and do not need to “reinvent the wheel” every time. It will also result in a consistent approach for all agency projects. A clear set of procedures also ensures that partner agencies and stakeholders understand how these effects will be considered. These procedures may be incorporated in an existing environmental procedures manual if one has been created by the agency. GHG emissions may also be incorporated in an air quality manual, if one has been created, given the degree of overlap between analysis of GHG emissions and other transportation-related air pollutants.
A potential template for agencies to follow when developing guidelines or procedures for considering GHG emissions and climate change effects might be as follows:
- If a climate change or sustainability office or team exists within the agency, hold a joint meeting with that office or team, environmental staff, project development staff, and any other key agency staff to discuss the overall procedural approach for developing guidance on GHG emissions and climate change effects. Ensure this approach aligns with any executive or legislative directives. Continue to coordinate with this group moving forward.
- Review programmatic or systems-level GHG emissions and vulnerability assessments conducted by the agency and determine whether these provide relevant information to inform project-level assessment. If a programmatic or systems-level assessment has not been conducted, discuss the feasibility, benefits, and potential level of effort of conducting one and the value of the information it might provide. As programmatic or systems-level GHG emissions and vulnerability assessments are updated, consider the need to modify project-level guidance and procedures to reflect new programmatic or systems-level findings.
- Review project development procedures and the degree to which GHG emissions and/or climate effects have already been considered within project development activities. Discuss whether there could be better consideration of these issues in the early phases of project development (e.g., establishment of purpose and need, definition of alternatives), and if so, how. If needed, work with project development staff to prepare policy or guidance for incorporating GHG emissions and/or climate effects in the early phases of project development.
- Include GHG emissions and climate change considerations in CE checklists.
- Identify existing procedures, tools, and methods for project-level traffic and air quality analysis and identify the degree to which those could support GHG emissions analysis. As appropriate, develop technical details (e.g., inputs to emission or traffic models) for inclusion within project-level guidance or procedures. Identify any additional data or methods that might be needed to estimate GHG emissions effects.
- Identify any existing procedures, tools, and methods for considering climate change effects, including equity impacts, in project-level environmental analysis, considering both affected communities and the implications for the design and operation of the project. Identify any additional data or methods that might be needed to consider and address climate change effects.
- Develop a menu of GHG emission mitigation options and resilience strategies to be considered at the project level, encouraging project sponsors to propose additional measures where they make sense. Develop a process for NEPA practitioners and agencies to work with design teams early on to ensure that mitigation and resilience measures developed under NEPA are practicable and compatible with project design.
- Develop procedures for project lead agencies to identify how GHG emissions mitigation and resilience commitments or considerations will be implemented as part of the project, specifying when mitigation would occur, which organizations will be responsible for implementation and monitoring, and how the community will be informed about implementation status.
- Develop processes for integrating mitigation and resilience strategies developed during NEPA through design completion, construction specifications, and maintenance procedures.
- Solicit input from partner agencies and stakeholder groups (e.g., community and environmental groups) on what changes the agency should make to better consider and address GHG emissions and climate change effects associated with projects.
- Create a draft set of policies, procedures, and technical methods for considering GHG emissions and climate change effects in environmental review. Test these procedures and methods on real or hypothetical projects.
- Share draft procedures and test results with partner agencies and stakeholders for feedback. Revise and finalize policies and procedures.
- Develop a communications and training program to inform relevant agency staff and the consultant community of the policies and procedures.
- Revisit policies and procedures after a suitable period of application to determine how well they are working, including level of effort and the value of information they are providing to inform decision-making. Also, revisit policies and procedures after enactment and implementation of new federal or state legislation or regulations to ensure consistency with new requirements. Modify policies and procedures as needed.
6.2.1 Benefits of a Departmental Policy
In some states, a written agency policy, which may be operationalized in a guidance or resource document, for considering greenhouse gas emissions and/or climate change is required by state legislation or at the governor’s direction. The requirements may be general, such as an overarching department-wide policy to coordinate on GHG emission reductions and climate adaptation and potentially to reduce GHG emissions by some amount consistent with state targets. The policy may also have more specific provisions, including provisions related to environmental review. Even when such provisions are not required, establishing a state department of transportation (DOT) policy specific to GHG and climate consideration in environmental review can have multiple benefits:
- It sends a message both to agency staff and the public that the DOT is aware of the transportation sector’s contribution to GHG emissions and the impact it has on climate change and is acting to document this impact and become “greener.”
- Spelling out the details provides consistency and clarity for environmental staff who are charged with overseeing project-level reviews and need to comply with federal and/or state guidance, and avoids the need to “reinvent the wheel” every time.
- A one-time review of the policy by federal lead and/or cooperating agencies (e.g., FHWA, FTA, Federal Railroad Administration, EPA) and other stakeholders (such as environmental and community groups) can help to streamline and expedite project-specific NEPA reviews.
If the agency is required to establish a policy, the legislation or executive order may include specific requirements for the policy. The agency may also decide to include elements that are not addressed in the legislation or executive order. For example, the 2019 New York State Climate Leadership and Community Protection Act (Section 75-0119, Paragraph 7) requires all state agencies involved with funding, permitting, or otherwise approving actions to “consider whether such decisions are inconsistent with or will interfere with the attainment of the statewide greenhouse gas emissions limits…” and “[W]here such decisions are deemed to be inconsistent with or will interfere with the attainment of the statewide greenhouse gas emissions limits, each agency, office, authority, or division shall provide a detailed statement of justification as to why such limits/criteria may not be met, and identify alternatives or greenhouse gas mitigation measures to be required where such project is located.” Other language in the Act spells out the need to not disproportionately burden disadvantaged communities and to prioritize reductions of GHG emissions in these communities. This is an example of climate legislation reaching down to the project level.
Many state DOTs publish resource documents to spell out their policies and procedures for environmental review. Sections related to GHG emissions and climate change effects could be added to such a resource document. This could be in addition to a general department-wide policy for addressing GHG emissions and climate change.
6.2.2 Elements of a Departmental Policy
A departmental GHG and climate change policy for environmental reviews may consider some of the following questions:
- Considerations across the stages of planning and project development:
- Should GHG emissions and/or climate change effects be evaluated at the planning or programming level, with reference to plan/program-level assessments in project documentation? Should effects only be considered at the project level? Or should planning-level analysis be conducted and referenced along with project-specific analysis, depending upon the project circumstances?
- How should information from a planning-level analysis be used to support or inform project-level assessment?
- Planning-level considerations:
- If a strategic GHG reduction or climate adaptation study has been (or will be) conducted, what should be the relationship of that study to the statewide Long-Range Transportation Plan (LRTP) and the Statewide Transportation Improvement Program (STIP)?
- Should a GHG and/or climate change effects assessment be conducted for the LRTP, STIP, or both?
- Should the assessment(s) be qualitative or quantitative?
- What requirements, if any, flow down to the metropolitan level for metropolitan LRTPs and TIPs? How will the state and MPOs coordinate on strategies, analysis, targets, etc.?
- Should assessment be conducted only on a plan or program-level for the build vs. no-build alternative, or for multiple plan or program alternatives?
- What scope of emissions should be included (modal, geographic, emissions sources, etc.)? What climate change effects should be considered?
- What tools, methods, and data sources should be used?
- Should STIP assessment include metrics related to GHG emissions and resilience for individual projects to support prioritization?
- How should equity related to emissions and climate change effects be considered?
- Should GHG reduction targets be set? On what basis? What actions might be taken if targets are not met?
- How will progress be measured and reported?
- Project-level considerations:
- Under what circumstances should a project have quantitative assessment(s) of GHG and/or climate change effects, qualitative assessment(s), or no assessment at all?
- What scope of emissions should be included (modal, geographic, emissions sources, etc.)? What climate change effects should be considered?
- What tools, methods, and data sources should be used?
- At what stage of project development should information first be developed? How should it be used to inform decision-making?
- How should equity related to emissions and climate change effects be considered?
- How should findings be reported? (e.g., absolute vs. percent changes, annual vs. cumulative effects, specific comparisons made)
- What (if any) criteria might be used to consider whether emissions and climate change effects are acceptable or not? What actions might be considered if they are not determined to be acceptable?
All of the above questions may be answered differently for GHG emissions than for climate change effects. For example, the department might determine that a planning-level analysis adequately covers GHG emissions effects for the vast majority of projects, but that a more detailed project-level analysis is necessary for climate change effects.
6.2.3 Examples in Practice
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The state DOTs of California, the District of Columbia, Minnesota, Oregon, Pennsylvania, and Virginia are all examples of agencies that have incorporated direction on GHG and/or climate change considerations in their project development and/or environmental review manuals. California[1] and Minnesota (Minnesota DOT undated) have done so in their forms and templates for project review. Colorado and the District of Columbia have done so in the air quality section of their environmental manuals (Colorado DOT 2023; District DOT 2012). Colorado, Oregon, Pennsylvania, and Virginia have done so or are planning to do so in their project-level air quality manuals or resource documents (Colorado DOT 2023; Oregon DOT 2018a; Pennsylvania DOT 2017; Virginia DOT undated).
Washington State DOT has established a stand-alone guidance document for project-level climate change evaluations that it updates regularly pursuant to NEPA and Washington’s State Environmental Policy Act (SEPA) (Washington State DOT 2022).
In some states, there are requirements set by the state executive office or environmental agency to which the DOT must adhere. For example, in Massachusetts, projects subject to the Massachusetts Environmental Policy Act that require an EIS must quantify emissions and reduce GHG emissions to the maximum amount feasible (Massachusetts EOEA 2010, 2021).
This section identifies a number of challenges and potential solutions that agencies might encounter when considering GHG emissions and climate change effects in environmental reviews.
Challenge: The available data and modeling tools are insufficient to reliably estimate critical aspects of project’s effects that might determine whether GHG emissions increase or decrease compared to the no-build alternative, and the general magnitude of the increase or decrease.
Potential solutions: (1) Apply sketch methods or screening tools to estimate the potential magnitude and direction of GHG impacts, applying sensitivity analysis to test uncertainties in key parameters. (2) If these potential impacts are small under a reasonable range of parameters, document the sensitivity analysis. (3) If the potential impacts are large, consider whether additional data collection and/or improved analysis methods are warranted.
Challenge: Modeling tools do not measure induced demand associated with a capacity expansion or operational improvement project.
Potential solutions: (1) Discuss with Planning or other agency staff with expertise in traffic and travel demand modeling how induced demand is captured in existing traffic and travel demand modeling policy and procedures. (2) Document the results of the outcome of the discussion. (3) Discuss potential induced demand effects qualitatively to reflect agency policy and procedure and the adequacy of existing policy and procedure to account for induced demand. (4) If needed, reference demand elasticities from the literature and perform a sensitivity analysis of how demand growth might affect emissions (magnitude and direction of impacts). (5) In the long term, identify potential enhancements to modeling systems to better account for induced demand.
Challenge: Climate model outputs include ranges that account for different assumptions regarding climate (low to high impact projections), as well as the time horizon (2020s to 2100s). These ranges present a challenge to infrastructure design teams.
Potential solutions: Agencies could address a part of this challenge by providing guidance regarding the types of climate impacts to include (e.g., sea level rise, extreme temperatures, storm surge, high winds), the time horizon, and climate scenario to be used for planning and design, based on the project type and location. Considerations on which part of the climate projection range to use or what time horizon to plan and design could depend on the criticality and value of the project, as well as the anticipated project lifetime. An approach might, therefore, include the following: (1) Evaluate potential impacts under a range of possible effects consistent with broadly defined and modeled scenarios. (2) Confirm that the project is consistent with the latest relevant design standards or exceeds these standards if needed to address potential effects. (3) Review existing and future vulnerability assessments and other studies to evaluate the adequacy of existing design standards. Consider updates to standards as needed to improve resiliency across the system.
Challenge: Available data on potential climate change effects (e.g., sea level rise, flooding) are of inadequate resolution to provide information on potential impacts of climate change on the project, or on the potential impacts of the project on the local environment.
Potential solutions: Agencies could encourage considerations of a dynamic adaptive pathways approach, whereby short and long-term resiliency actions are identified and evaluated during planning and implemented over time and in response to identified climate effects identified as triggers.
Challenge: Evaluation of potential climate change effects on the project suggests that designs exceeding current standards may be warranted to withstand potential extreme weather impacts; however, funding cannot be used for costs incurred in excess of existing standards.
Potential solutions: (1) Develop design standards to meet project needs, using the best available vulnerability assessments and other studies, as needed. (2) For projects on the Interstate or NHS systems, request a waiver from FHWA, if needed. (3) In the long term, consider updates to standards as needed to improve resiliency across the system.
Challenge: Stakeholders feel that the NEPA process is too late to effectively consider GHG emissions or climate change effects and argue that different alternatives should have been evaluated and advanced.
Potential solutions: (1) Ensure that broad-based stakeholder input has been critically considered in the project’s scoping, Purpose and Need, definition of alternatives, and evaluation criteria for those alternatives. (2) Document the public input that was received and clearly justify the basis of decisions made. (3) As consideration of alternatives can sometimes be constrained by the scope of decisions that can be undertaken by a specific agency, consider broadening the alternative options that would achieve the project purpose by encouraging co-lead agencies for projects whose purpose and need could be satisfied by multiple modes or a mix of modes.
Challenge: Some stakeholders believe that the project will create effects that cause disproportionate harm or do not proportionately benefit disadvantaged communities related to climate change effects, e.g., by exacerbating flooding in low-income neighborhoods.
Potential solutions: (1) Ensure that the public input process has solicited broad-based and meaningful input from all affected communities, including disadvantaged communities. (2) Critically evaluate the potential negative and beneficial effects through an equity lens, looking at who benefits and who is negatively impacted. (3) If negative impacts appear disproportionate, or if disadvantaged communities do not receive an equal share of the benefits, consider revisions to the project and/or mitigation measures.
Challenge: State climate change legislation or executive orders often establish emission reduction targets, i.e., a certain emission reduction by a certain year. Public or stakeholder input asks how the transportation project affects the ability to attain those targets (especially for large or major transportation projects).
Potential solutions: States that have established emission reduction strategies typically develop a Climate Action Plan (or other similar document) that identifies and quantifies the emission reduction potential of various emission reduction strategies, including strategies for the transportation sector. Evaluate and document the consistency of the project with the Climate Action Plan, including a comparison of quantitative emissions effects with any emissions effects from similar project or strategy types in the plan. Provide a qualitative discussion of how the project may facilitate (or hinder) the implementation of strategies in the plan.
[1] Caltrans (undated). Standard Environmental Reference Forms and Templates. https://dot.ca.gov/programs/environmental-analysis/standard-environmental-reference-ser/forms-templates