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Environmental Review Toolkit

NEPA Transportation Decisionmaking

CEQ regulations (40 CFR ยงยง 1500-1508) address the basic decisionmaking framework and action forcing provisions established in NEPA. The principles or essential elements of NEPA decisionmaking include:

  • Assessment of the social, economic, and environmental impacts of a proposed action or project
  • Analysis of a range of reasonable alternatives to the proposed project, based on the applicants defined purpose and need for the project
  • Consideration of appropriate impact mitigation: avoidance, minimization and compensation
  • Interagency participation: coordination and consultation
  • Public involvement including opportunities to participate and comment
  • Documentation and disclosure.

FHWA adopted the policy of managing the NEPA project development and decisionmaking process as an "umbrella," under which all applicable environmental laws, executive orders, and regulations are considered and addressed prior to the final project decision and document approval. Conclusion of the NEPA process results in a decision that addresses multiple concerns and requirements. The FHWA NEPA process allows transportation officials to make project decisions that balance engineering and transportation needs with social, economic, and natural environmental factors. During the process, a wide range of partners including the public, businesses, interest groups, and agencies at all levels of government, provide input into project and environmental decisions.

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Public Involvement Overview

FHWA Policy:

Public involvement and a systematic interdisciplinary approach are essential parts of the development process for proposed actions.
23 CFR § 771.105(c)

FHWA’s Public Involvement Requirements

Each State must have procedures approved by the FHWA to carry out a public involvement/public hearing program pursuant to 23 U.S.C. 128 and 40 CFR parts 1500 through 1508.

State public involvement/public hearing procedures must provide for:

  • Coordination of public involvement activities and public hearings with the entire NEPA process.
  • Early and continuing opportunities during project development for the public to be involved in the identification of social, economic, and environmental impacts, as well as impacts associated with relocation of individuals, groups, or institutions.
  • One or more public hearings or the opportunity for hearing(s) to be held by the State highway agency at a convenient time and place for any Federal-aid project which requires significant amounts of right-of-way, substantially changes the layout or functions of connecting roadways or of the facility being improved, has a substantial adverse impact on abutting property, otherwise has a significant social, economic, environmental or other effect, or for which the FHWA determines that a public hearing is in the public interest.
  • Reasonable notice to the public of either a public hearing or the opportunity for a public hearing. Such notice will indicate the availability of explanatory information. The notice shall also provide information required to comply with public involvement requirements of other laws, Executive Orders, and regulations.

23 CFR § 771.111(h)

Project sponsors should use a combination of in-person and virtual public involvement for public hearings and meetings during the environmental review process. Each State should include in their public involvement/public hearing program, procedures to address the use of both in-person and virtual public involvement techniques, to be approved under 23 CFR 771.111(h).

Under the National Environmental Policy Act (NEPA), public involvement may take many forms, including public meetings and public hearings (40 CFR 1506.6). Public hearings and public meetings under NEPA may be entirely electronic except where otherwise required by law, although agencies deciding on the method(s) for such activities must consider the ability of affected entities to access electronic media (40 CFR 1506.6(c)).1

Section 128, U.S.C., requires States to hold a public hearing, or provide an opportunity for a public hearing, on projects meeting broad statutorily defined criteria. FHWA’s environmental review regulations, 23 CFR Part 771, expand on the circumstances when a public hearing is required in 23 CFR 771.111(h)(2)(iii). The term “public hearing” is not defined in the statute or regulation. FHWA interprets “public hearing” as used in 23 U.S.C. 128 and 23 CFR 771.111(h)(2)(iii) to require an opportunity for interested persons to physically appear before agency officials and other hearing participants to express their views about the proposed project. However, the in-person component of the hearing can be supplemented and enhanced by other methods of public involvement, such as virtual public involvement strategies.

Additional information on virtual public involvement can be found on FHWA’s website at:

The SAFETEA-LU Environmental Review Process Final Guidance on coordination and schedule provides information on how lead agencies should establish a plan for coordinating public and agency participation and comment during the environmental review process. It also provides guidance on updating public involvement procedures to help state DOTs determine if they need to update their public involvement procedures, pursuant to 23 CFR § 771.111(h).

Other Resources

Promising Practices for Meaningful Public Involvement in Transportation Decision-Making, November 8, 2023
Use of DOT Funds for Public Involvement
Additional FHWA Information on Public Involvement
Virtual Public Involvement
Public Involvement and its Role in Project Development
Public Involvement Techniques for Transportation Decisionmaking

1 The President’s Council on Environmental Quality addressed the scope of permissible electronic-based public involvement in its 2020 revisions to the governmentwide NEPA regulations at 40 CFR 1500 et seq.

Virtual Public Involvement (VPI) Practices in the National Environmental Policy Act (NEPA) - Webinars

In February 2024, FHWA hosted a series of webinars featuring presenters from State DOTs that incorporated VPI in the NEPA process. The presentations showcased projects that held public hearings, including comment periods between March 2020 and fall 2021 when in-person gatherings were restricted due to the COVID-19 pandemic.

  • Session 1 (2/27/24): featuring presenters from North Carolina DOT, South Carolina DOT, Maryland DOT, and Multnomah County, Oregon. Recording (Password: n$1KG%6V).
  • Session 2 (2/28/24): featuring presenters from Iowa DOT, Michigan DOT, and Kansas DOT. Recording (Password: y$9V.rQ1).

Please see the VPI in NEPA Case Studies for more information about the history, VPI approaches, outreach to underserved populations, benefits, challenges, lessons learned, and next steps of the featured projects.

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Interagency Coordination

The combined requirements of the National Environmental Policy Act (NEPA) of 1969 and Title 23 United States Code create a challenging position for the Federal Highway Administration (FHWA) in carrying out its transportation mission. Title 23 restricts Federal funding to those projects that meet certain engineering, environmental, and safety requirements. Under NEPA, as the lead Federal agency and "owner" of the resultant environmental document, FHWA assumes responsibility for the integrity of the NEPA process.

As lead Federal agency in the NEPA process, FHWA is responsible for scoping, inviting cooperating agencies, developing consensus among a wide range of stakeholders with diverse interests, resolving conflict, and ensuring that quality transportation decisions are fully explained in the environmental document. These responsibilities force the FHWA to balance transportation needs, costs, environmental resources, safety, and public input in order to arrive at objective and responsible transportation decisions.

The FHWA Environmental Policy Statement stresses the full involvement of all partners:

Effective communication is critical to successful implementation of FHWA’s transportation mission and environmental policy. This has become increasingly evident as we have worked with our partners to fuse the environmental and planning processes and to merge the FHWA, NEPA, and related project development procedures with other Federal, State, and local requirements. We must continually strive to communicate our commitment to protect and enhance the environment. We must increase our partnerships with private enterprise on infrastructure investments, including transit and Intelligent Transportation System (ITS) initiatives. Bringing together the multifaceted and diverse interests in an open and cooperative process creates a synergy that will produce positive and effective solutions.

It is FHWA policy to:

  • Pursue communication and collaboration with Federal, state, and local partners in the transportation and environmental communities, including other modal administrations within the U.S. DOT.
  • Seek new partnerships with tribal governments, businesses, transportation and environmental interests groups, resource and regulatory agencies, affected neighborhoods, and the public.
  • Ensure that those historically underserved by the transportation system, including minority and low-income populations, are included in outreach.
  • Actively involve partners and all affected parties in an open, cooperative, and collaborative process, beginning at the earliest planning stages and continuing through project development, construction, and operations.
  • Ensure the development of comprehensive and cooperative public involvement programs during statewide and metropolitan planning and project development activities.

Collaborative Decisionmaking

Effective interagency coordination is the key to achieving environmentally responsible transportation decisions. The Council on Environmental Quality (CEQ) regulations introduced the concepts of "lead agency" and "cooperating agency" to help streamline the environmental process, eliminate duplication in Federal, state, and local procedures, and integrate NEPA requirements with other Federal environmental review and consultation requirements.

SAFETEA-LU further defined the role of agencies involved with a transportation project receiving Federal funds. The SAFETEA-LU Environmental Review Process Final Guidance, issued November 15th, 2006, defines the role of Lead Agencies, Participating Agencies, and Cooperating Agencies. The purpose of the environmental streamlining provisions are to coordinate Federal agency involvement in major highway projects under the NEPA process and to address concerns relating to delays in implementing projects, unnecessary duplication of effort, and added costs often associated with the conventional process for reviewing and approving surface transportation projects.

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Elements of Purpose and Need

The purpose and need of a project is essential in establishing a basis for the development of the range of reasonable alternatives required in an EIS and assists with the identification and eventual selection of a preferred alternative.

The following items may be listed and described in the purpose and need statement for a proposed action. These are by no means all-inclusive or applicable in every situation. They are intended as a guide.

  • Project Status — Briefly describe the action’s history, including measures taken to date, other agencies and governmental units involved, action spending, schedules, etc.
  • Capacity — Discuss the capacity of the present facility and its ability to meet present and projected traffic demands. Discuss the capacity and performance goals for existing and proposed facilities and any recurring or non-recurring causes that may limit the capacity of the present facility or affect travel time reliability.
  • System Linkage — Discuss if the proposed action is a "connecting link" and how it fits into the transportation system. Such linkages may be physical or operational.
  • Transportation Demand — Discuss the action’s relationship to any statewide or regional transportation demand management plans or programs. Consider how transportation demand varies over the typical day or longer time periods. In addition, explain any related traffic forecasts that are substantially different from those estimates of the 23 U.S.C. 134 (Section 134) planning process.
  • Legislation — Explain if there is a Federal, state, or local governmental mandate for the action.
  • Social Demands or Economic Development — Describe how the action will foster new employment and benefit schools, land use plans, recreation facilities, etc. In addition, describe projected economic development/land use changes that indicate the need to improve or add to the highway capacity.
  • Modal Interrelationships — Explain how the proposed action will interface with and serve to complement airports, rail and port facilities, mass transit services, etc.
  • Safety — Explain if the proposed action is necessary to correct an existing or potential safety hazard. In addition, explain if the existing accident rate is excessively high and why, and how the proposed action will improve safety.
  • Roadway Deficiencies — Explain if and how the proposed action is necessary to correct existing roadway deficiencies (e.g., substandard geometrics, load limits on structures, inadequate cross-section, high maintenance costs, etc.) In addition, explain how the proposed action will correct these deficiencies.

Other Resources

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Helpful Documents

Development and Evaluation of Alternatives

Information on alternatives analysis can be found in the FHWA/FTA SAFETEA-LU Environmental Review Process Final Guidance, November 15, 2006. On this page, learn about: Alternatives Screening, Range of Alternatives, Logical Termini and Segmentation, and Other Requirements Involving Alternatives Analysis.

The identification, consideration, and analysis of alternatives are key to the NEPA process and goal of objective decisionmaking. Consideration of alternatives leads to a solution that satisfies the transportation need and protects environmental and community resources. The Council on Environmental Quality (CEQ) refers to the alternatives analysis section as the "heart of the EIS," and requires agencies to:

  1. Rigorously explore and objectively evaluate all reasonable alternatives and for alternatives which were eliminated from detailed study, briefly discuss the reasons for their having been eliminated.
  2. Devote substantial treatment to each alternative considered in detail including the proposed action so that reviewers may evaluate their comparative merits.
  3. Include reasonable alternatives not within the jurisdiction of the lead agency.
  4. Include the alternative of no action.
  5. Identify the agency’s preferred alternative or alternatives, if one or more exists, in the draft statement and identify such alternative in the final statement unless another law prohibits the expression of such a preference.
  6. Include appropriate mitigation measures not already included in the proposed action or alternatives.

-- 40 CFR1502.14

Alternatives Screening

Alternatives analysis should clearly indicate why and how the particular range of project alternatives was developed, including what kind of public and agency input was used. In addition, alternatives analysis should explain why and how alternatives were eliminated from consideration. It must be made clear what criteria were used to eliminate alternatives, at what point in the process the alternatives were removed, who was involved in establishing the criteria for assessing alternatives, and the measures for assessing the alternatives’ effectiveness.

In preparing NEPA documents, project sponsors should be candid about the rationale for generating, evaluating, and eliminating alternatives. Being as specific as possible is important. If an alternative is eliminated from further consideration because it "does not meet the purpose and need," we must adequately explain how or why this alternative doesn’t meet the purpose and need.

Range of Alternatives

During the draft EIS stage all reasonable alternatives, or the reasonable range of alternatives, should be considered and discussed at a comparable level of detail to avoid any indication of a bias towards a particular alternative(s).

Although the "no-build alternative" (which might include short-term minor activities) might not seem reasonable, it must always be included in the analysis. In some cases, the no-build alternative may be a reasonable alternative, especially when the impacts are great and the need is relatively minor, but generally it serves as a baseline against which the other alternatives can be compared.

Alternatives that do not add capacity are often evaluated as potential design options. Transportation Systems Management and Operations (TSMO) can offer such alternatives such as Active Transportation and Demand Management (ATDM), congestion pricing strategies, expanding multimodal alternatives and mobility services, traffic signal synchronization, and other strategies. Also, where appropriate, multimodal options should be considered even when they are outside FHWA’s funding authority. For more information on TSMO, visit the FHWA "What is TSMO?" Website.

Logical Termini and Segmentation

In order to ensure meaningful evaluation of alternatives and to avoid commitments to transportation improvements before they are fully evaluated, the action evaluated in each environmental impact statement (EIS) or finding of no significant impact (FONSI) shall:

  1. Connect logical termini and be of sufficient length to address environmental matters on a broad scope;
  2. Have independent utility or independent significance, i.e., be usable and be a reasonable expenditure even if no additional transportation improvements in the area are made; and
  3. Not restrict consideration of alternatives for other reasonably foreseeable transportation improvements.

-- 23 CFR771.111(f)

When developing a transportation project, project sponsors should consider how the end points of the action are determined, both for the improvement itself and for the scope of the environmental analysis. Whether the action has "logical termini" or not is also a concern. Logical termini for project development are defined as rational end points for both a transportation improvement and a review of the environmental impacts.

In developing a concept that can be advanced through the stages of planning, environment, design, and construction, the project sponsor needs to consider a "whole" or integrated action. This action should satisfy an identified need, such as safety, rehabilitation, economic development, or capacity improvement. In addition, the action should be considered in the context of local socio-economics and topography, future travel demand, and other infrastructure improvements. Without framing an action in this way, project sponsors may only peripherally meet project needs or may cause unexpected side effects that require additional corrective action. Project sponsors should also be aware of the problem of "segmentation." Segmentation may occur when a transportation need extends throughout an entire corridor, but project sponsors discuss the environmental issues and transportation need of only a segment of the corridor.

An FHWA memo dated November 5, 1993 provides additional guidance on the development of logical termini.

Other Requirements Involving Alternatives Analysis

(Source: FHWA Guidance on Purpose and Need Statements)

Beyond the CEQ requirement of evaluating all or a reasonable number representative of the full spectrum of reasonable alternatives, there are other requirements for analyzing alternatives. These requirements fall under Section 4(f), the Executive Orders on Wetlands and Floodplains, and the Section 404(b)(1) guidelines. To address these requirements and conclusively demonstrate that some alternatives are not prudent or practicable, project sponsors must develop a well-justified purpose and need statement.

The use of land from a Section 4(f) protected property (such as a significant, publicly owned park, recreation area, or wildlife and waterfowl refuge, or any significant historic site) may not be approved unless a determination is made that there is no feasible and prudent alternative for such use. Many factors exist that could render an alternative "not prudent," including cost and environmental impacts. If an alternative does not meet the action’s purpose or need, then the alternative is not prudent, provided the purpose and need section can substantiate that unique problems will be caused by not developing the action.

If a proposed action is to be located in a wetland or significantly encroaches upon a floodplain, a finding must be made that there is no practicable alternative to the wetland take or floodplain encroachment. Any alternative that does not meet the need for the action is not practicable. If the action’s purpose and need are not adequately addressed, specifically delineated, and properly justified, resource agencies, interest groups, the public, and others will be able to generate one or possibly several alternatives that avoid or limit the impact and "appear" practicable. A well-described justification of the action’s purpose and need may prevent long and involved negotiations or additional analyses demonstrating that an alternative is not practicable.

As a rule, if an alternative does not satisfy the purpose and need for the action, it should not be included in the analysis as an apparent and reasonable alternative. There are times when an alternative that is not reasonable is included, such as when another agency requests inclusion due to public expectation. In such cases, it should be clearly explained why the alternative is not reasonable (or prudent or practicable), why it is being analyzed in detail, and why it will not be selected.

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The CEQ regulations (40 CFR §§ 1508.7 and 1508.8) define the impacts and effects that must be addressed and considered by Federal agencies in satisfying the requirements of the NEPA process, which includes direct, indirect and cumulative impacts:

Cumulative impact

"Cumulative impact" is the impact on the environment which results from the incremental impact of the action when added to other past, present, and reasonably foreseeable future actions regardless of what agency (Federal or non-Federal) or person undertakes such other actions. Cumulative impacts can result from individually minor but collectively significant actions taking place over a period of time.

-- 40 CFR 1508.7


"Effects" include:

(a) Direct effects, which are caused by the action and occur at the same time and place.

(b) Indirect effects, which are caused by the action and are later in time or farther removed in distance, but are still reasonably foreseeable. Indirect effects may include growth inducing effects and other effects related to induced changes in the pattern of land use, population density or growth rate, and related effects on air and water and other natural systems, including ecosystems.

Effects and impacts as used in these regulations are synonymous. Effects includes ecological (such as the effects on natural resources and on the components, structures, and functioning of affected ecosystems), aesthetic, historic, cultural, economic, social, or health, whether direct, indirect, or cumulative. Effects may also include those resulting from actions which may have both beneficial and detrimental effects, even if on balance the agency believes that the effect will be beneficial.

-- 40 CFR 1508.8

Significance of Environmental Impacts

According to the Council on Environmental Quality (CEQ) regulations (40 CFR §§ 1500-1508), the determination of a significant impact is a function of both context and intensity.

Context: This means that the significance of an action must be analyzed in several contexts such as society as a whole (human, national), the affected region, the affected interests, and the locality. Significance varies with the setting of the proposed action. For instance, in the case of a site-specific action, significance would usually depend upon the effects in the locale rather than in the world as a whole. Both short- and long-term effects are relevant.

Intensity: This refers to the severity of impact. Responsible officials must bear in mind that more than one agency may make decisions about partial aspects of a major action. The following should be considered in evaluating intensity:

  1. Impacts that may be both beneficial and adverse. A significant effect may exist even if the Federal agency believes that on balance the effect will be beneficial.
  2. The degree to which the proposed action affects public health or safety.
  3. Unique characteristics of the geographic area such as proximity to historic or cultural resources, park lands, prime farmlands, wetlands, wild and scenic rivers, or ecologically critical areas.
  4. The degree to which the effects on the quality of the human environment are likely to be highly controversial.
  5. The degree to which the possible effects on the human environment are highly uncertain or involve unique or unknown risks.
  6. The degree to which the action may establish a precedent for future actions with significant effects or represents a decision in principle about a future consideration.
  7. Whether the action is related to other actions with individually insignificant but cumulatively significant impacts. Significance exists if it is reasonable to anticipate a cumulatively significant impact on the environment. Significance cannot be avoided by terming an action temporary or by breaking it down into small component parts.
  8. The degree to which the action may adversely affect districts, sites, highways, structures, or objects listed in or eligible for listing in the National Register of Historic Places or may cause loss or destruction of significant scientific, cultural, or historical resources.
  9. The degree to which the action may adversely affect an endangered or threatened species or its habitat that has been determined to be critical under the Endangered Species Act of 1973.
  10. Whether the action threatens a violation of Federal, State, or local law or requirements imposed for the protection of the environment.

-- 40 CFR 1508.27

To determine significance, the severity of the impact must be examined in terms of the type, quality and sensitivity of the resource involved; the location of the proposed project; the duration of the effect (short- or long-term) and other consideration of context. Significance of the impact will vary with the setting of the proposed action and the surrounding area (including residential, industrial, commercial, and natural sites).

NEPA significance is a primarily factor in determining the type of environmental document and process to use for a particular project. NEPA requires an EISfor major Federal actions that significantly affect the quality of the human environment. To determine the appropriate class of action and the requisite level of documentation necessary to comply with NEPA, it is essential to understand the term "significance" and the process for its determination.

The Environmental Consequences page provides information on discussing potentially significant environmental impacts in an EIS.

Other Resources

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Mitigation of Environment Impacts

The NEPA process is intended to help public officials make decisions that are based on understanding of environmental consequences, and take actions that protect, restore, and enhance the environment.

-- 40 CFR § 1500.1(b): Purpose

Federal agencies shall to the fullest extent possible:

Use all practicable means consistent with the requirements of the Act and other essential considerations of nation policy, to restore and enhance the quality of the human environment and avoid or minimize any possible adverse effects of their actions on the quality of the human environment.

-- 40 CFR 1500.2(f)

The mitigation of impacts must be considered whether or not the impacts are significant. ("Forty Most Asked Questions and Answers on the CEQ Regulations" Number 19a). Agencies are required to identify and include in the action all relevant and reasonable mitigation measures that could improve the action.

The CEQ regulations define mitigation as:

  • Avoiding the impact altogether by not taking a certain action or parts of an action.
  • Minimizing impacts by limiting the degree or magnitude of the action and its implementation.
  • Rectifying the impact by repairing, rehabilitating, or restoring the affected environment.
  • Reducing or eliminating the impact over time by preservation and maintenance operations during the life of the action.
  • Compensating for the impact by replacing or providing substitute resources or environments.

-- 40 CFR 1508.20

Mitigation: Avoid → Minimize → Repair or Restore → Reduce over time → Compensate

This ordered approach to mitigation is known as "sequencing" and involves understanding the affected environment and assessing transportation effects throughout project development. Effective mitigation starts at the beginning of the NEPA process, not at the end. Mitigation must be included as an integral part of the alternatives development and analysis process.

FHWA’s mitigation policy states:

Measures necessary to mitigate adverse impacts will be incorporated into the action and are eligible for Federal funding when the Administration determines that:

  1. The impacts for which the mitigation is proposed actually result from the Administration action; and
  2. The proposed mitigation represents a reasonable public expenditure after considering the impacts of the action and the benefits of the proposed mitigation measures. In making this determination, the Administration will consider, among other factors, the extent to which the proposed measures would assist in complying with a Federal statute, Executive Order, or Administration regulation or policy.

-- 23 CFR 771.105(d)

Additional Information

Context Sensitive Solutions