National Environmental Policy Act (NEPA)

graphic showing the NEPA process

President Nixon signed the National Environmental Policy Act (NEPA) into law on January 1, 1970. NEPA was the first major environmental law in the U.S. and established this country's national environmental policies. To implement these policies, NEPA requires agencies to undertake an assessment of the environmental effects of their proposed actions prior to making decisions. Two major purposes of the environmental review process are better informed decisions and citizen involvement. For more information on citizen involvement you can read A Citizen's Guide to the NEPA.

NEPA requires the examination of potential impacts to the natural and human environment when considering approval of proposed federally funded transportation projects by the Federal Highway Administration (FHWA). FHWA adopted the policy of managing the NEPA project development and decision-making 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.

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. In accordance with NEPA, it is the policy of the FHWA that the essential elements of the project-development process include:

  • Define the Purpose and Need for the project
  • Evaluate a full range of reasonable Alternatives
  • Assessment of potential social, economic, and environmental impacts with consideration to avoid, minimize, and mitigate impacts
  • Mitigate environmental impacts to the extent practical and feasible
  • Interagency coordination and consultation
  • Public involvement including opportunities to participate and comment
  • NEPA documentation and disclosure

Please view the Summary of the National Environmental Policy Act for more information about the NEPA.