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Chapter 16 - Climate Change

What Does This Topic Include?

This topic covers the regulatory framework, an overview and background for general climate change (greenhouse gas [GHG] emissions and adaptation) and recommended procedures for conducting climate change analysis and evaluation for projects on the State Highway System (SHS) for which Caltrans is the lead agency under CEQA. The primary GHG emissions associated with transportation projects are discussed as well as anticipated changes in future climate conditions. Preparation of the climate change section of the environmental document, including analysis requirements, is discussed in detail. There is also guidance on making determinations for the California Environmental Quality Act (CEQA) checklist GHG questions and addressing sea level rise and other climate change considerations for projects.

Laws, Regulations, and Guidance Related to Climate Change (GHG and Adaptation)

See also SER, Chapter 1, "Federal Requirements" and Chapter 2, "State Requirements" for laws and regulations that apply to all environmental analysis activities.

The primary laws and guidance related to GHG emissions and climate change stem from California state legislation, such as Assembly Bill (AB) 32 and Senate Bill (SB) 32, as there is currently no comprehensive federal law specific to climate change or the reduction of GHG emissions. However, the United States Environmental Protection Agency (U.S. EPA) and National Highway Traffic Safety Administration (NHTSA) implement fuel efficiency standards that have a direct effect on GHG emissions. The United States has also submitted a Nationally Determined Contribution (NDC) under the Paris Agreement, which aims to reduce national GHG emissions by 50 to 52 percent by 2030 from 2005 levels.

On January 9, 2023, CEQ issued National Environmental Policy Act Guidance on Consideration of Greenhouse Gas Emissions and Climate Change, interim guidance to assist agencies in analyzing greenhouse gas and climate change effects of their proposed actions under the National Environmental Policy Act.  An analysis of project generated GHG emissions is required under CEQA. This includes an additional analysis of greenhouse gas emissions as a cumulative impact due to the global nature of climate change (Pub. Resources Code, § 21083(b)(2)). As the California Supreme Court explained, “because of the global scale of climate change, any one project's contribution is unlikely to be significant by itself.” (Cleveland National Forest Foundation v. San Diego Assn. of Governments (2017) 3 Cal.5th 497, 512.) In assessing cumulative impacts, it must be determined if a project's incremental effect is "cumulatively considerable" (CEQA Guidelines Sections 15064(h)(1) and 15130).

To make this determination, the incremental impacts of the project must be compared with the effects of past, current, and probable future projects. Although climate change is ultimately a cumulative impact, not every individual project that emits greenhouse gases must necessarily be found to contribute to a significant cumulative impact on the environment.

Analysis of GHG emissions can be described as the impact of the transportation system on the environment, while impacts related to climate stressors may be considered the impact of the environment on the project. At this time, analysis of potential climate change impacts to the project is not explicitly required under CEQA, unless the project will exacerbate the impacts of those stressors. However, state agencies are required to consider climate change in all planning and investment decisions, pursuant to Executive Order (EO) B-30-15 and subsequent policies.

The following laws, regulations, orders, and guidance are relevant to the analysis of GHG emission and climate change impacts. Additional regulatory information is provided below under Regulatory Setting.

Federal Laws, Regulations, and Orders

Greenhouse Gas Emissions

Adaptation and Climate Change

  • Federal Highway Administration (FHWA) Order 5520 (2014) – The purpose of this directive is to establish the FHWA policy on preparedness and resilience to climate change and extreme weather events. 
  • Executive Order 13990 (2021) – This Executive Order directs all executive departments and agencies to immediately review and, as appropriate and consistent with applicable law, take action to address the promulgation of Federal regulations and other actions during the last 4 years that conflict with these important national objectives, and to immediately commence work to confront the climate crisis.
  • Executive Order 14008 (2021) – The EO has three overarching objectives 1) promote safe global temperature, 2) increase climate resilience, and 3) support a financial pathway toward low greenhouse gas emissions and climate-resilient development. The EO reinstates the Presidential Memorandum of September 21, 2016 (Climate Change and National Security), establishes the Climate Policy Office within the Executive Office of the President, and establishes a National Climate Task Force. In addition, the EO aims to use Federal procurement to support robust climate action including a carbon pollution-free electricity sector, no later than 2035 and clean and zero-emission vehicles for Federal, State, local, and Tribal government fleets.

State Laws, Regulations, and Orders

Greenhouse Gas Emissions

  • Executive Order S-3-05 (2005) – Established a GHG emission reduction target for California to reduce GHG emissions to 80 percent below 1990 levels by 2050.
  • Assembly Bill 32 (2006) –Set a target for 2020 greenhouse gas levels to be reduced to 1990 levels.
  • Executive Order S-20-06 (2006) – Directs state departments to implement a cap-and-trade program.
  • Senate Bill 97 (2007) – Requires the Governor’s Office of Planning and Research (“OPR”) to prepare CEQA guidelines for the mitigation of GHG emissions, including, but not limited to, effects associated with transportation or energy consumption.
  • Executive Order S-01-07 (2007) – Formally established the Low Carbon Fuel Standard (LCFS) and directs CARB to determine if an LCFS can be adopted pursuant to AB 32. In 2009, CARB introduced the LCFS, and it took effect in 2011.
  • Senate Bill 32 (2006) – Increased and extended the emission reduction mandate to 40 percent below 1990 levels by 2030.
  • Executive Order B-30-15 (2015) –Established a new interim greenhouse gas reduction target of 40 percent below 1990 levels and directed state agencies to take additional actions to prepare for the impacts of climate change.
  • Assembly Bill 134 (2017) – Takes $900 million of funds derived from auctioning off carbon allowances and puts it into incentives for reducing emissions from cars, trucks, buses, and other engines.
  • Executive Order B-55-18 (2018) – Set a statewide target to achieve carbon neutrality no later than 2045.
  • Executive Order N-19-19 (2019) – Requires every aspect of state government redouble its efforts to reduce greenhouse gas emissions and mitigate the impacts of climate change while building a sustainable, inclusive economy.
  • Assembly Bill 1279 (2022) – The California Climate Crisis Act: Mandates carbon neutrality by 2045. Solidifies a goal included in executive order B-55-18. Requires the state board to work with relevant state agencies to ensure that updates to the scoping plan identify and recommend measures to achieve these policy goals and to identify and implement a variety of policies and strategies that enable carbon dioxide removal solutions and carbon capture, utilization, and storage technologies in California, as specified.
  • Assembly Bill 1493 (2022) – Directs CARB to set carbon-dioxide emission standards from vehicle exhaust to "achieve the maximum feasible reduction of greenhouse gases" from cars, light-duty trucks, and other non-commercial vehicles.

Adaptation and Climate Change

  • McAteer-Petris Act (1965), Government Code Title 7.2 – The San Francisco Bay Conservation and Development Commission (BCDC) administers permits for projects in the coastal zone which includes most transportation projects along the Bay's nine-county shoreline wherein projects must demonstrate consistency with the Bay Plan’s 8 Policies; expectations for climate change including sea level rise is provided in the 2021 Climate Change Policy Guidance. BCDC also coordinates with local governments, regional councils of government, and other agencies and interested parties in development of regional climate change adaptation strategies as part of the Adapting to Rising Tides program.
  • Porter-Cologne Water Quality Control Act (1969), Water Code Division 7 and Related Sections – For sea level rise, as part of the Bay Area Basin Plan Amendment adopted in July 2022, Signed Resolution R2-2022-0027 contains a set of questions to support climate change and adaptation considerations that minimize adverse impacts to the aquatic ecosystem in permitting necessary for fill or dredge activities (California Regional Water Quality Control Board, San Francisco Bay Region 2022).
  • California Coastal Act (1976), Public Resources Code Division 20 – The primary law governing coastal management, land use and development, public access and recreation, and protection of coastal resources in the Coastal Zone. The California Coastal Commission and local agencies with certified Local Coastal Programs (LCPs) will evaluate how sea level rise was analyzed throughout the Caltrans project development process when Coastal Development Permits (CDPs) are required for Caltrans projects (Sections 30001.5(f) and 30421). The Coastal Commission bases its standard of review for CDPs on the Chapter 3 policies, Sections 30235, 30236, and 30253 focus on coastal hazards and shoreline development. Specific to transportation, section 30253(d) requires that VMT be minimized.
  • Senate Bill 375 (2008) – Gave the California Air Resources Board authority over sources of greenhouse gas emissions, including cars and light trucks and directed the California Air Resources Board to set regional targets for reducing greenhouse gas emissions.
  • Executive Order S-13-08 (2008) – Directs state agencies to complete analysis of the effects of sea level rise on California.
  • Senate Bill 391 (2009) – Required the Department of Transportation to update the California Transportation Plan by December 31, 2015, and every 5 years thereafter. The bill required the plan to address how the state will achieve maximum feasible emissions reductions in order to attain a statewide reduction of greenhouse gas emissions to 1990 levels by 2020 and 80% below 1990 levels by 2050.
  • Executive Order B-16-12 (2012) – Directed state government to help accelerate the market for zero-emission vehicles (ZEVs) in California and calling for 1.5 million ZEVs in California by 2025.
  • Senate Bill 743 (2013) – SB 743 requires the amount of driving and length of trips – as measured by "vehicle miles traveled" or VMT (instead of being based on the potential increase in traffic) – be used to assess transportation impacts on the environment for CEQA review. 
  • Assembly Bill 1482 (2015) – Requires state agencies to maximize specified objectives, including, among others, promoting the use of the climate adaptation strategy to inform planning decisions and ensure that state investments consider climate change impacts, as well as promote the use of natural systems and natural infrastructure, as defined, when developing physical infrastructure to address adaptation.
  • Senate Bill 379 (2015) – Requires local General Plans to include climate change vulnerability assessments, measures to address vulnerabilities, and a comprehensive hazard mitigation and emergency response strategy.
  • Senate Bill 1386 (2016) – Declares it to be state policy that protecting and managing natural and working lands is key to meeting California's climate change goals and directs all relevant state agencies to consider this policy when conducting their work.
  • Assembly Bill 2800 (2016) – Requires state agencies to take into account the current and future impacts of climate change when planning, designing, building, operating, maintaining, and investing in state infrastructure.
  • Senate Bill 150 (2017) – Requires the California Air Resources Board to prepare a report to the Legislature starting in 2018, and every four years thereafter, to discuss progress related to the Sustainable Communities Act, or SB 375, implementation. This progress report uses data-supported metrics to assess progress on transportation, housing, and land use strategies, identifies best practices and challenges to achieving greater reductions, and discusses the impact of State policies and funding.
  • Senate Bill 1 (2017) – To the extent deemed cost effective, and where feasible, in the context of both the project scope and the risk level for the asset due to global climate change, the Department of Transportation and cities and counties receiving funds under the program shall include features in the projects funded by the program to better adapt the asset to withstand the negative effects of climate change and make the asset more resilient to impacts such as fires, floods, and sea level rise.
  • Executive Order B-52-18 (2018) – Establishes a goal of treating 500,000 acres of vegetation per year to reduce wildfire risk.
  • Executive Order N-82-20 (2020) – Directs the State to accelerate and expand use of nature-based solutions while mitigating greenhouse gas emissions to adapt and become more resilient to the impacts of climate change through conserving 30 percent of California’s land and coastal waters by 2030.
  • Senate Bill 1 (2021) – Declared that the impacts of sea level rise are both environmental and economic, including losses to publicly owned infrastructure, such as airports, rail lines, streets and highways, pipelines, wastewater treatment plants, schools, hospitals, and other facilities. The purpose of the declaration is to establish new planning, assessment, funding, and mitigation tools for California to address and respond to sea level rise.

Caltrans Climate Change Policies

Climate Action Plan for Transportation Infrastructure

The California Action Plan for Transportation Infrastructure (CAPTI) builds on executive orders signed by Governor Newsom in 2019 and 2020 targeted at reducing GHG emissions in transportation, which account for more than 40 percent of all polluting emissions, to reach the state's climate goals. Under CAPTI, where feasible and within existing funding program structures, the state will invest discretionary transportation funds in sustainable infrastructure projects that align with its climate, health, and social equity goals (California State Transportation Agency 2021). 

California Transportation Plan

The California Transportation Plan (CTP) is a statewide, long-range transportation plan to meet our future mobility needs and reduce GHG emissions. It serves as an umbrella document for all the other statewide transportation planning documents. The CTP 2050 presents a vision of a safe, resilient, and universally accessible transportation system that supports vibrant communities, advances racial and economic justice, and improves public and environmental health. The plan’s climate goal is to achieve statewide GHG emissions reduction targets and increase resilience to climate change. It demonstrates how GHG emissions from the transportation sector can be reduced through advancements in clean fuel technologies; continued shifts toward active travel, transit, and shared mobility; more efficient land use and development practices; and continued shifts to telework (Caltrans 2021a).

Senate Bill (SB) 391 (Liu 2009) requires the CTP to meet California’s climate change goals under Assembly Bill (AB) 32. Accordingly, the CTP identifies the statewide transportation system needed to achieve maximum feasible GHG emission reductions while meeting the state’s transportation needs. While Metropolitan Planning Organizations (MPOs) have primary responsibility for identifying land use patterns to help reduce GHG emissions, the CTP identifies additional strategies.

Caltrans Strategic Plan

The Caltrans 2020–2024 Strategic Plan includes goals of stewardship, climate action, and equity. Climate action strategies include developing and implementing a Caltrans Climate Action Plan; a robust program of climate action education, training, and outreach; partnership and collaboration; a vehicle miles traveled (VMT) monitoring and reduction program; and engaging with the most vulnerable communities in developing and implementing Caltrans climate action activities (Caltrans 2021b).

Funding and Technical Assistance Programs

In addition to developing plans and performance targets to reduce GHG emissions, Caltrans also administers several Sustainable Transportation Planning Grants. These grants encourage and support projects that improve local and statewide infrastructure climate resiliency along with the development of multimodal transportation and other adaptation strategies. This also includes technical assistance projects for under-resourced and climate vulnerable communities to perform climate adaptation planning.

Caltrans Policy Directives and Other Initiatives

Caltrans Director’s Policy 30 (DP-30) Climate Change (June 22, 2012) established a Caltrans policy to ensure coordinated efforts to incorporate climate change into Caltrans’ decisions and activities.

The Caltrans Greenhouse Gas Emissions and Mitigation Report (2020), (found under the Technical Resources, Tools and Training tab) provides a comprehensive overview of Caltrans’ emissions. The report documents and evaluates current Caltrans procedures and activities that track and reduce GHG emissions and identifies additional opportunities for further reducing GHG emissions from Caltrans-controlled emission sources, in support of Caltrans and state goals.

Caltrans Climate Change Vulnerability Assessments

Caltrans conducted climate change vulnerability assessments to identify segments of the State Highway System (SHS) vulnerable to climate change effects including precipitation, temperature, wildfire, storm surge, and sea level rise. The approach to the vulnerability assessments was tailored to the practices of a transportation agency, and involves the following concepts and actions:

  • Exposure – Identify Caltrans assets exposed to damage or reduced service life from expected future conditions.
  • Consequence – Determine what might occur to system assets in terms of loss of use or costs of repair.
  • Prioritization – Develop a method for making capital programming decisions to address identified risks, including considerations of system use and/or timing of expected exposure.

The climate change data in the assessments were developed in coordination with climate change scientists and experts at federal, state, and regional organizations at the forefront of climate science. The findings of the vulnerability assessments will guide analysis of at-risk assets and development of adaptation plans to reduce the likelihood of damage to the SHS, allowing Caltrans to both reduce the costs of storm damage and to provide and maintain transportation that meets the needs of all Californians. The Caltrans Vulnerability Assessments accompanying interactive maps for each district are posted on the 2019 Climate Change Vulnerability Assessments page.  

District-specific adaptation priorities reports were prepared in 2020 and can be found on the Division of Transportation Planning’s page.

Resources/References

Definitions

The following terms are commonly used in the discussion and analysis of climate change and adaptation. Several definitions are adopted from California’s Fourth Climate Change Assessment (2018), Paying it Forward: The Path Toward Climate-Safe Infrastructure in California(2018), and Planning and Investing for a Resilient California: A Guidebook for State Agencies (2017).

Term Definition
Adaptation Adjustment in natural or human systems in response to actual or expected climatic stimuli or their effects, which moderates harm or exploits beneficial opportunities.   Planning for and responding to impacts to reduce vulnerability and increase resilience. Adaption strategies may include protect, accommodate, or retreat.
Adaptive capacity   The combination of the strengths, attributes, and resources available to an individual, community, society, or organization that can be used to prepare for and undertake actions to reduce adverse impacts, moderate harm, or exploit beneficial opportunities.”
Anthropogenic The term "anthropogenic" in the context of greenhouse gas inventories, refers to greenhouse gas emissions and removals that are a direct result of human activities or are the result of natural processes that have been affected by human activities.
Avoidance and minimization measures (AMMs) Actions to further reduce effects (NEPA) or less-than-significant impacts (CEQA).
CEQA mitigation Actions to reduce significant impacts under CEQA to less than significant.
Climate change Atmospheric changes caused by global warming (or cooling) including changes in hot and cold weather, average sea level, ocean water composition, and amounts and timing of rain and snow.
Climate change mitigation GHG reduction
Climate-safe infrastructure Infrastructure that is sustainable, adaptive, and that meets design criteria that aim for resilience in the face of shocks and stresses caused by current and future climate.
Exposure The presence of people, infrastructure, natural systems, and economic, cultural, and social resources in areas that are subject to harm.
Global warming An increase in average global temperature that results from increasing greenhouse gas (GHG) emissions, mostly from human activities.
Greenhouse effect Warming of the Earth caused by excess accumulation of GHGs that slow the rate at which energy escapes to space, like a blanket insulating the planet.
Greenhouse gases (GHGs) Gases in the atmosphere that absorb the sun’s energy to moderate the temperature of the atmosphere. GHGs include carbon dioxide, methane, nitrous oxide, water vapor, and fluorinated gases. Each gas has a different capacity to trap heat.
Resilience The capacity of any entity—an individual, a community, an organization, or a natural system—to prepare for disruptions, to recover from shocks and stresses, and to adapt and grow from a disruptive experience. Adaptation actions contribute to increasing resilience, which is a desired outcome or state of being.
Sensitivity The level to which a species, natural system, or community, government, etc., would be affected by changing climate conditions.
Vulnerability The susceptibility to harm from exposure to stresses associated with environmental and social change and from the absence of capacity to adapt. Vulnerability can increase because of physical (built and environmental), social, political, and/or economic factor(s). These factors include, but are not limited to ethnicity, class, sexual orientation and identification, national origin, and income inequality. Vulnerability is often defined as the combination of sensitivity and adaptive capacity as affected by the level of exposure to a changing climate.

Background

Climate Change Basics

Climate change refers to long-term changes in temperature, precipitation, wind patterns, and other elements of the Earth's climate system. The research of the Intergovernmental Panel on Climate Change (IPCC) and other scientists over recent decades has unequivocally attributed an accelerated rate of climatological changes over the past 150 years to GHG emissions generated from the production and use of fossil fuels. Human activities generate GHGs consisting primarily of carbon dioxide (CO2), methane (CH4), nitrous oxide (N2O), tetrafluoromethane, hexafluoroethane, sulfur hexafluoride (SF6), and various hydrofluorocarbons (HFCs). CO2 is the most abundant GHG; while it is a naturally occurring and necessary component of Earth’s atmosphere, fossil-fuel combustion is the main source of additional, human-generated CO2 that is the main driver of climate change. In the U.S. and in California, transportation is the largest source of GHG emissions, consisting mostly of CO2.

In California and elsewhere, the impacts of climate change are already being observed in the form of sea level rise, drought, extended and increasingly severe fire seasons, and historic flooding from changing storm patterns. The most important strategy to address climate change is to reduce GHG emissions. California has been innovative and proactive in addressing GHG emissions and climate change by passing multiple Senate and Assembly bills and executive orders, as listed above. To comply with legislation and policies, Caltrans must demonstrate how projects will be adapted or resilient to climate change effects. Addressing vulnerabilities in the transportation system involves long-term planning and risk management. This process must begin at the earliest stages of system, corridor, and project planning.

State and National GHG Emissions Inventories

The California Air Resources Board (CARB) collects GHG emissions data for transportation, electricity, commercial/residential, industrial, agricultural, and waste management sectors each year. It then summarizes and highlights major annual changes and trends to demonstrate the state’s progress in meeting its GHG reduction goals, and posts annual reports and data on its California Greenhouse Gas Emission Inventory Program webpages.

Assembly Bill 32 required CARB to develop a Scoping Plan that describes the approach California will take to achieve the goal of reducing GHG emissions to 1990 levels by 2020, and to update it every 5 years. CARB adopted the first scoping plan in 2008. The second updated plan, California’s 2017 Climate Change Scoping Plan, adopted on December 14, 2017, reflects the 2030 target established in EO B-30-15 and SB 32. The AB 32 Scoping Plan and the subsequent updates contain the main strategies California will use to reduce GHG emissions.

The U.S. EPA conducts nationwide GHG data collection and publishes an annual inventory of U.S. greenhouse gas emissions and sinks.

When preparing the GHG analysis for environmental documents, check both the CARB and U.S. EPA sites against the Caltrans Climate Change Annotated Outlines on the SER Forms and Templates page to ensure you are presenting the latest information.

According to the IPCC’s fifth assessment in Climate Change 2014 Synthesis Report: Summary for Policymakers, warming of the climate system is unequivocal (IPCC 2014). Global average air and ocean temperatures as well as global average sea level have risen, while amounts of snow and ice have decreased. Eleven of the 12 years from 1995–2006 ranked as among the warmest on record since 1850 (IPCC 2007), and many observed changes since the 1950s are unprecedented over decades to millennia (IPCC 2014). While some of the increase is explained by natural processes, the IPCC’s 2014 update report concludes that it extremely likely that anthropogenic GHG emissions and other human drivers are the main cause of observed warming since the mid-20th century. The report notes that “emissions of CO2 from fossil fuel combustion and industrial processes contributed about 78% of the total GHG emissions increase from 1970 to 2010, with a similar percentage contribution for the increase during the period 2000 to 2010” (IPCC 2014).

For California, similar effects are described in the 2019 California Fourth Climate Change Assessment. Based on projections using state-of-the-art climate modeling, temperatures are expected to rise between 5.6- and 8.8-degrees Fahrenheit by the end of the century, depending on the level of GHG emissions. The report states that these temperature increases will have negative impacts on public health, water supply, agriculture, plant and animal species, and the coastline. [See California Climate Change Center. Our Changing Climate: Assessing the Risks to California (July 2008), p. 1.]  Climate change is also expected to decrease snowfall and winter snowpack; change precipitation patterns and increase the frequency, intensity, and duration of extreme storms; and increase extreme heat conditions. These changes can affect California’s transportation system by leading to increased risk of flooding, slope failure, and landslides that block roadways; cause heat damage to roads, railroad tracks, and bridge joints; and result in system disruptions from washouts and wildfire.

Climate change may also exacerbate the indirect effects of projects on resources. For instance, when a project reduces the area of important habitat, remaining habitat may be further impaired by warming or reduced precipitation.

Impacts of Projects on Climate Change

Projects affect climate change by directly and indirectly generating GHG emissions. GHG emissions from transportation projects can be divided into those produced during operation and use of the SHS (operational emissions) and those produced during construction. The primary GHGs produced by the transportation sector are CO2, CH4, N2O, and HFCs. CO2 emissions are a product of burning gasoline or diesel fuel in internal combustion engines, along with relatively small amounts of CH4 and N2O. A small amount of HFC emissions related to refrigeration is also included in the transportation sector.

The CEQA Guidelines generally address greenhouse gas emissions as a cumulative impact due to the global nature of climate change (Pub. Resources Code, § 21083(b)(2)). As the California Supreme Court explained, “because of the global scale of climate change, any one project's contribution is unlikely to be significant by itself.” (Cleveland National Forest Foundation v. San Diego Assn. of Governments (2017) 3 Cal.5th 497, 512.)

Adaptation

Reducing GHG emissions is only one part of an approach to addressing climate change. The state must plan for the effects of climate change on the state’s transportation infrastructure and strengthen or protect transportation facilities from damage. Projects must plan for and address threats of changes in sea level rise, precipitation and riverine flooding, wildfire, and temperature to transportation assets.

Climate change adaptation for transportation infrastructure involves long-term planning and risk management to address vulnerabilities in the transportation system. California’s Fourth Climate Change Assessment (2018) is the state’s effort to “translate the state of climate science into useful information for action” in a variety of sectors at both statewide and local scales.

Key Case Law Decisions

Cleveland National Forest Foundation v. San Diego Assn. of Governments (2017)

Center for Biological Diversity v. California Department of Fish and Wildlife (2015)

Eureka Citizens for Responsible Gov’t v. City of Eureka (2007)

Berkeley Keep Jets Over the Bay v. Bd. Of Port Commissioners (2001)

Mission Bay Alliance v. Office of Community Investment & Infrastructure (2016)

Protect the Historic Amador Waterways v. Amador Water Agency (2003)

Ballona Wetlands Land Trust v. City of Los Angeles (2011)

Interagency Coordination

Greenhouse Gas Emissions

With respect to GHG emissions, Caltrans has the primary responsibility for the climate change/GHG analysis and oversight (advisory) responsibility for Caltrans projects on the SHS. No interagency coordination on greenhouse gas analysis specifically is required by state or federal regulations.[See Caltrans and the Coastal Commission Partnership Agreement.]

Adaptation

California legislation and executive orders such as those listed in the Laws, Regulations, and Guidance section above direct state agencies to consider climate change in general and sea level rise in their planning and investment decisions. Accordingly, Caltrans has implemented policies to consider and report the potential effects of climate change on projects and must endeavor to design assets to be protected from or resilient to climate-related impacts. Caltrans coordinates with other state agencies to obtain various permits for Caltrans projects that may have an impact on the environment. Under AB 1282 (Mullin 2017), Caltrans participated in a multi-agency Transportation Permitting Task Force to develop a structured coordination process for early engagement with permitting agencies to streamline the processing of permit applications for transportation projects. “Early” is defined as the period from the planning/scoping phase of an individual project (e.g., Project Initiation Document (PID) or Preliminary Environmental Study (PES) process) through the completion of the draft environmental document or prior to issuing a CEQA exemption. For simple projects or those that do not require permits, early coordination is optional. It is, however, advisable for all projects to consult with both State and local agencies with jurisdiction in a project area to coordinate with regional or local climate change adaptation plans and efforts as well as to ensure Caltrans' documentation will meet permitting requirements. For further guidance on coordination please see the Caltrans Coastal Program webpage and the AB 1282 Transportation Permitting Task Force 2019 Final Report.

Reporting

Greenhouse Gas Emissions

No technical reports for GHG emissions are mandated by state or federal law. For projects that increase capacity or are highly controversial, Caltrans requires a quantitative analysis of changes in operational GHG emissions. It should generally be presented in the body of the environmental document, but a complex or lengthy analysis may also be prepared as a separate technical report or memo using the GHG analysis section of the Climate Change Annotated Outline as a guide. If creating a standalone document, include a summary project description to provide context for the climate change analysis. The results may then be summarized in the environmental document to support the CEQA significance determination.

All projects must report construction GHG emissions in the environmental document, including CEQA exemptions/NEPA categorical exclusions (CE/CE). GHG emissions are generally calculated at the PID phase or in the air quality report or memo or can be requested from the project’s air quality specialist. Include the results in the CE along with any Standard Specifications and project avoidance and minimization measures that co-benefit GHG emissions. Preserve the air quality report or memo in the project file. Additional information on analysis methods is presented below under Information Needed for Environmental Document.

Adaptation

All projects must conduct a project-level adaptation analysis to demonstrate the project’s resilience to future climate change effects. For projects in the Coastal Zone or the Sacramento-San Joaquin Delta, environmental documents must include a discussion of sea level rise risks and adaptation measures, as instructed in the Climate Change Annotated Outlines. The sea level rise risk assessment and analysis should be developed in phases from the earliest planning stages, and the decision-making process and conclusions reported in the environmental document. For projects requiring specialized studies such as wave run-up or other risk factors, a separate sea level rise technical report may be warranted. Consult the Caltrans Sea-Level Rise Guidance Update (in preparation) for detailed guidance on sea level rise analysis.

Processing and Approval of Technical Reports

Submit the climate change chapter of the environmental document, the separate GHG and/or sea level rise technical reports if applicable, and other supporting documents to the district climate change reviewer. Technical reports may be submitted for review prior to or concurrent with preparation of the environmental document.

Information Needed for Project Delivery

Regional Transportation Plan

The Regional Transportation Plan (RTP) and corresponding environmental document prepared by the MPO or Regional Transportation Planning Agency (RTPA) for the project region provide information that should inform the climate change analysis and serve as a building block in subsequent decision making.

  • The RTP establishes a purpose and need for regionally significant projects.
  • Identify if your project is included in a current or prior RTP.
  • The RTP or its EIR may provide recommendations of project-level mitigation measures for GHGs and for other resources that could co-benefit GHG reduction. These measures should be considered and adapted for inclusion in your project and listed in the Project-Level GHG Reduction Strategies section of the climate change chapter and in the environmental commitments record.

Early Coordination with the Project Development Team

Consideration of potential GHG and climate change impacts should begin as early in the project development process as possible. The district Environmental Generalist should bring climate change issues to the attention of the Project Development Team (PDT) at the first team meeting. Considerations include ensuring the appropriate level of analysis of GHG emissions for the project (quantitative or qualitative) and screening for and addressing the impacts of climate change (e.g., sea level rise, changing precipitation, wildfire risk). Changes in design, materials, project features, and other adaptive or preventive measures that would protect the asset and the environment, including potential for location change, are best scoped into the project at the earliest planning stages. Hydraulics, traffic, construction, landscape, and maintenance functions may need to augment their analysis and reporting methods to address climate change concerns, which could require additional resources. Necessary resources should be accounted for in the PID, Preliminary Environmental Analysis Report (PEAR) or Mini-PEAR, and Transportation Planning Scoping Information Sheets (TPSIS). Appropriate resource-specific best management practices and specifications that help reduce GHG emissions or promote resilience should also be scoped at this stage.)

Early Coordination with Regulatory Agencies

Caltrans coordinates with other state agencies to obtain various permits for Caltrans projects that may have an impact on the environment. Under AB 1282 (Mullin 2017), Caltrans participated in a multi-agency Transportation Permitting Task Force to develop a structured coordination process for early engagement with permitting agencies to streamline the processing of permit applications for transportation projects. “Early” is defined as the period from the planning/scoping phase of an individual project (e.g., PID or Preliminary Environmental Study process) through the completion of the draft environmental document or prior to issuing a CEQA exemption. For simple projects or those that do not require permits, early coordination is optional. It is, however, advisable for all projects to consult with both state and local agencies with jurisdiction in a project area to coordinate with regional or local climate change adaptation plans and efforts as well as to ensure Caltrans' documentation will meet permitting requirements. For further guidance on coordination with the California Coastal Commission, please see the Caltrans Coastal Program webpage. Special attention is drawn to the Caltrans and the Coastal Commission Partnership agreement and the AB 1282; Transportation Permitting Task Force 2019 Final Report.

Project Initiation Document

The following information should be included in the Energy and Climate Change section of the PEAR prepared as part of the PID.

  • Acknowledge the potential for construction activities or operations to result in GHG emissions and identify potential GHG reduction strategies.
  • Determine the need for a quantitative operational GHG analysis. Scope time and resources needed.
  • Identify if the project is within the Coastal Zone or in a location subject to sea level rise, and therefore will require a sea level rise analysis. Scope necessary time and resources.
  • Identify if the project/project limits will be at risk due to projected climate stressors. Risks and proposed adaptation measures should be included in the PID.
  • Plan and resource any needed early coordination meetings.

Draft Project Report

This is the stage where the bulk of GHG/climate change analysis is done. Detailed analyses for all viable alternatives and the no-build alternative are completed. If a sea level rise analysis is required, it would be completed and or refined at this stage. The following information should be included in the draft environmental document (DED) or used as supporting documentation for a CE, as appropriate.

  • Identify project-level strategies that will be implemented to reduce GHG emissions and adapt to future anticipated climate change impacts in the draft project report. Summarize information that has been identified within the environmental document. 

Draft and Final Environmental Document

Refer to “Information Needed for Environmental Document” section below.

Project Report

The climate change section may be revised after circulation and public comment on the DED. To the extent that potential impacts or GHG reduction or adaptation strategies change, that information should be reflected in the final environmental document (FED) and final project report.

Environmental Re-evaluation

GHG and climate changes issues should be re-examined and updated as necessary whenever an environmental re-validation is done. This is especially critical for projects that did not include GHG analysis or adaptation discussions in the original environmental document.

Environmental Commitments

The Resident Engineer is responsible for ensuring all environmental commitments are implemented. An Environmental Commitment is a measure that Caltrans or a local agency commits to implement to avoid, minimize and/or mitigate a real or potential environmental impact. It can be identified as early as the planning and scoping stages, during the environmental document or design processes, or as late as construction or maintenance of a project. These commitments may include permit conditions along with project specific GHG reduction measures. These are listed in the Environmental Commitments Record (ECR).

Typical environmental commitments related to Climate Change include:

  • According to the Caltrans’s Standard Specifications, the contractor must comply with all local Air Quality Management District rules, ordinances, and regulations for air quality restrictions.
  • The contractor will use diesel construction equipment meeting ARB's Tier 2 certified engines or cleaner off-road heavy-duty diesel engines and comply with the State Off-Road Regulation.
  • The contractor will use on-road heavy-duty trucks that meet the ARB’s 2007 or cleaner certification standard for on-road heavy duty diesel engines and comply with the State Off-Road Regulation.
  • All on and off-road diesel equipment shall not idle for more than 5 minutes. Signs shall be posted in the designated queuing areas and or job sites to remind drivers and operators of the 5-minute idling limit.
  • The contractor shall use electric equipment in place of diesel-powered equipment, where feasible.
  • The contractor will substitute gasoline-powered in place of diesel-powered equipment, where feasible.
  • The contractor shall use alternatively fueled construction equipment onsite where feasible, such as compressed natural gas (CNG), liquefied natural gas (LNG), propane or biodiesel.
  • Incorporate complete streets elements such as pedestrian and bicycle facilities.
  • Incorporate the use of energy-efficient lighting, such as LED traffic signals. LED bulbs cost $60 to $70 each, but last five to six years, compared to the one-year average lifespan of the incandescent bulbs previously used. The LED bulbs themselves consume 10 percent of the electricity of traditional lights, which will also help reduce the project’s CO2 emissions.

Information Needed for Environmental Document

Content and Recommended Format

Caltrans uses a standard format for impact discussions in its environmental documents. See the SER Forms and Templates page for annotated outlines that include Caltrans-approved content and recommended format for the climate change section.

  • Climate Change Annotated Outline Capacity Increasing
  • Climate Change Annotated Outline Non-Capacity Increasing

For combined CEQA/NEPA documents (IS/EA, EIR/EA, EIR/EIS), standard text near the end of the Air Quality section of the annotated outline includes a Climate Change subheading and a short paragraph pointing to the CEQA Climate Change section stating that the CEQA analysis will be used to inform the NEPA determination for the project.

The climate change annotated outline should be used to complete the Climate Change section within the CEQA/NEPA documents.

The Climate Change section of CEQA/NEPA documents should discuss the following items, as indicated in the annotated outlines.

  • Regulatory Setting (optional)
  • Environmental Setting
  • Project Analysis
  • Greenhouse Gas Reduction Strategies
  • Adaptation

The two climate change annotated outlines include the same standard language for all sections except Project Analysis. The content for Project Analysis is different for capacity increasing projects and non-capacity increasing projects, as discussed further below.

Regulatory Setting (optional)

The Climate Change Annotated Outlines include boilerplate language and a brief discussion of the regulatory framework for the analysis, including local, state, and federal laws. A comprehensive list of relevant laws, regulations, and guidance is provided above.

Environmental Setting

Describe the project location in general terms, from the perspective of factors that affect transportation GHG emissions, such as urban or rural setting, land uses, development density, traffic congestion, and economy. Identify the transportation agency or regional transportation plan that guides transportation development and addresses GHG emissions in the project area. Recognize that some locations are subject to policies in both metropolitan planning organizations and local regional transportation planning agencies. General and state plan elements may also address GHGs in the project area.

  • Use the standard language in the approved annotated outline to describe current national and state GHG inventories, including figures and statistics. Do check the CARB and U.S. EPA GHG emission inventory websites to make sure the information is up to date.
  • Discuss relevant regional plans and their GHG reduction policies or strategies under the Regional Plans subheading. Include, as appropriate, regional or metropolitan transportation plans, climate action plans, general plan elements, and active transportation or bicycle plans.

Project Analysis

Under CEQA (Section 15064.4), the lead agency “should make a good faith effort, based to the extent possible on scientific and factual data, to describe, calculate or estimate the amount of GHG emissions resulting from a project.” The lead agency has the discretion to address GHG emissions from a project through either qualitative or quantitative methods. Under Section 15064.4, the lead agency should also consider 1) the extent to which the project may increase or reduce GHG emissions relative to the existing environmental setting; 2) whether the project emissions exceed a threshold of significance that the lead agency determines applies to the project and 3) the extent to which the project complies with regulations or requirements adopted to implement a statewide, regional, or local plan for the reduction or mitigation of greenhouse gas emissions. Note that Caltrans has not established a GHG emissions threshold of significance for Caltrans projects.

Use the following decision tree to assess whether a project requires a quantitative or qualitative GHG analysis. Refer to the Interim Guidance: Determining CEQA Significance for Greenhouse Gas Emissions for Projects on the State Highway System for further instruction on completing the analysis, incorporating GHG reduction measures, and making the CEQA impact determination.

GHG Analysis Methodology Overview

GHG Analysis Methodology Overview (PDF) | GHG Analysis Methodology Overview (ADA version)

Recommended Methodologies

Operational GHG Emissions

Capacity-Increasing Projects

Capacity-increasing projects require a quantitative analysis using Emission FACtor (CT-EMFAC) and vehicle miles traveled (VMT) data to estimate operational GHG emissions. Ensure the VMT data in the climate change section are consistent with VMT presented in the traffic and air quality analyses and cite accordingly. Conduct separate model runs for existing/baseline conditions and the horizon/design-year for both the build and no-build alternatives. It is also helpful to include an intermediate year such as the open-to-traffic year. In the discussion, compare the GHG emissions numbers for the alternatives (including the no-build alternative) in the opening year and design-year to existing/baseline emissions. The comparison of design-year to baseline GHG emissions will be the basis of the CEQA impact determination. Also compare the design-year build alternative to the design-year no-build alternative. Reporting VMT here also provides context for discussing whether changes in GHG emissions can be attributed to the project. Revise the table’s footnotes as needed. Note that the VMT analysis and discussion of induced travel should be presented in the Traffic/Transportation section, not in the climate change section. VMT is used in this section as an input for the calculation of GHG emissions. Reporting VMT here also provides context for discussing whether changes in GHG emissions can be attributed to the project.

Identify the applicable RTP/SCS that applies to the region in which the proposed project is located. Discuss how the project is designed to reduce VMT, reduce congestion, and/or reduce vehicle time delays, and provide the supporting data. Provide a discussion of the early planning aspects of the project and how the modal choice was made.

Note that CARB has released the latest EMFAC model update, EMFAC2021.

Refer to the Climate Change Annotated Outline Capacity Increasing.

Non-Capacity-Increasing Projects

For non-capacity-increasing projects, provide a qualitative discussion about the operation of the project and the low to no potential for an increase in operational GHG emissions. If the project is a ramp metering or signalization project, provide a discussion of what traffic-smoothing effects the project will have; to the extent that the signal or meter provides a smoother traffic flow, there will likely be an overall reduction in GHGs emitted. If the backup at the ramp meters or signals will be lengthy, then conduct a quantitative analysis using EMFAC as described above for congestion relief/capacity-increasing projects.

Refer to the Climate Change Annotated Outline Non-Capacity Increasing

Considerations for Maintenance of Roadway Facilities

Project maintenance and owner-operator activities are likely to generate GHG emissions from the operation of fossil-fueled maintenance vehicles and equipment, as well as indirect emissions through electricity generation for any electrical equipment onsite, such as lighting or cameras. Vehicle trips used for maintenance purposes would be temporary, and any generated VMT would generally be minor and limited to maintenance equipment and personnel and would not result in long-term trip generation. There are currently no regulations that require monitoring of GHGs emitted during maintenance or traffic management activities.

Construction GHG Emissions

GHG emissions related to anticipated construction activities must be calculated for all projects. Use a readily available model such as the California Emissions Estimator Model (CalEEMod) OR the Caltrans Construction Emissions Tool (CAL-CET). Emissions estimates are generally prepared by the project air quality specialist. Include the calculation results in a brief sentence or two stating the expected construction duration and the total expected GHG emissions for the construction period.

Discuss any additional specifications or construction measures included in the project that will further contribute to reducing construction GHG emissions.

CEQA Conclusion

All Caltrans CEQA documents above a CE must make a determination for the two CEQA Appendix G checklist questions for greenhouse gases:

  1. Would the project generate greenhouse gas emissions, either directly or indirectly, that may have a significant impact on the environment?
  2. Would the project conflict with an applicable plan, policy, or regulation adopted for the purpose of reducing the emissions of greenhouse gas?

Refer to the Interim Guidance: Determining CEQA Significance for Greenhouse Gas Emissions for Projects on the State Highway System for step-by-step guidance on making a CEQA significance determination.

Greenhouse Gas Reduction Strategies

This section should contain a general discussion of statewide and Caltrans efforts to reduce GHG emissions from its projects. The Climate Change Annotated Outlines provide standard text.

Identify and list all feasible measures to reduce project-level GHG emissions from operations and construction. These can include Standard Specifications, Standard Special Provisions, Nonstandard Special Provisions, requirements of the air quality management district, project-specific construction-emissions reduction measures, and measures intended to reduce effects to other environmental resources. The strategies listed in the section are environmental commitments. Accordingly, they must be written as actions with responsible parties (“biddable and buildable”) and recorded in the Environmental Commitments Record or District equivalent. Strategies may come from other resource topics, such as air quality and traffic; and from the relevant RTP, climate action plan, and air quality management district rules or recommendations. Revise them as necessary to read as specific actions that are within Caltrans’ control; Caltrans must be able to verify they were implemented at project close-out. (Measures listed under Construction Emissions may be repeated in this section.)

Refer to the Interim Guidance: Determining CEQA Significance for Greenhouse Gas Emissions for Projects on the State Highway System, GHG Reduction Measures Toolbox for Internal Use in Caltrans Project Development, and Caltrans Greenhouse Gas Emissions and Mitigation Report for potential reduction strategies.

Adaptation

This section should contain a general discussion of federal, state, and Caltrans adaptation efforts. The Climate Change Annotated Outlines provide standard text.

All Caltrans projects must conduct a project-level adaptation analysis. The environmental document should specifically consider future climate impacts from sea level rise, changes in precipitation and riverine flood risk, changes in high and low temperatures, and increased wildfire risk, as applicable to your District. If your District has a completed a Climate Change Vulnerability Assessment, you may use that information to assess which climate change effects are most likely to occur in your project area. Consult the additional resources and guidance in the Climate Change Annotated Outlines.

Discussion of adaptation measures should also describe environmental resources present in the project location that may benefit from or be adversely impacted by project adaptation features or alternatives. Environmental resources could include riparian or tidal wetlands, environmentally sensitive habitat areas, habitat areas for listed or endangered species.

Note that if the project is within the Coastal Zone (requiring approval of a coastal development permit, Local Coastal Program amendment, or approval from the San Francisco Bay Conservation and Development Commission) or in a location subject to sea level rise (e.g., within the Sacramento-San Joaquin River Delta region), a sea level rise analysis is required. Use the tools and guidance in the Climate Change Annotated Outlines and the latest Caltrans sea level rise guidance to identify any potential sea level rise impacts that may occur.

For projects specifically within the coastal zone, review SER Volume 5: Coastal Requirements to identify and address typical use restrictions, common concerns addressed through coastal development review, and common technical study requirements. Early coordination with the California Coastal Commission or local coastal program is critical to determine the appropriate level of study and to avoid lengthy project delays. Coordination and analysis of sea level rise should begin in the earliest project planning phase so that the PID and PEAR adequately consider adaptation options/alternatives and account for time and resources needed to complete studies before PA&ED.

(Last content update: 08/30/2023, JH)