Environmental Review Toolkit

Section 4(f) Tutorial

Related Statutes


This portion of the tutorial will acquaint you with Section 106 of the National Historic Preservation Act (NHPA) and Section 6(f) of the Land and Water Conservation Fund Act (LWCFA). When you have finished, you should have a basic understanding of the following:

  • The purpose of both related statutes (Sections 106 and 6[f])
  • The relevance of both related statutes to Section 4(f)
  • The differences between Section 4(f) and Sections 106 and 6(f)


Two statutes that are independent from, but related to, Section 4(f) must be considered during Section 4(f) compliance—Section 106 of the NHPA of 1966, and Section 6(f) of the LWCFA. Section 106 applies to historic sites; Section 6(f) applies to some recreational properties.

SECTION 106 (36 CFR PART 800)

The purpose of Section 106 is for Federal agencies to consider the effects of their undertakings on historic sites that are on or eligible for the National Register of Historic Places (NRHP). The Nation's official list of historic properties worthy of preservation. If impacts result, agencies should seek ways to avoid, minimize or resolve those effects that are considered adverse. Agency consultation between the parties in the Section 106 process (including the State Historic Preservation Officer (SHPO) and/or the Tribal Historic Preservation Officer (THPO) if on tribal lands, and the Advisory Council on Historic Preservation (ACHP)), supports the tasks of the identification of historic properties, consideration of effects, and the resolution of adverse effects to impacted properties.


Section 4(f) stipulates that in order for a historic site to be granted protection, it must be considered significant. The Section 106 process is the method by which a historic site’s significance is determined.


Sections 106 and 4(f) are similar in that they both mandate consideration of historic sites in the planning of a federal undertaking. But despite their similarities, the two statutes have some key differences. An important distinction between them is that Section 106 considers project effects to "historic properties," Section 4(f) considers whether there is a use of "historic properties." Under Section 4(f), agencies of the U.S. Department of Transportation (DOT) must avoid the use of historic sites. If no prudent and feasible alternative exists that avoids the use, then the agency must employ all possible planning to minimize harm to historic sites (and other property types) resulting from use of the properties by the project. In this way, Section 4(f) has a substantive requirement that requires historic sites to be avoided, while Section 106 requires “historic properties” to be identified and project impacts be considered.
Additional important differences between the two statues include:

  • Section 4(f) applies only to programs and projects undertaken by agencies of the U.S. DOT, while Section 106 applies to actions of any federal agency.
  • Section 4(f) applies to the actual use or occupancy of a historic site, while Section 106 involves an assessment of adverse effects of an action on historic properties. There is no direct correlation between "use" in the Section 4(f) context and "adverse effect" in the Section 106 context.
  • The Section 106 process is integral to the Section 4(f) process when historic sites are involved. The Section 4(f) process is not integral to the Section 106 process.
  • The Section 4(f) process applies a more stringent analysis with respect to totally avoiding historic properties than does the Section 106 process.

SECTION 6(f) (36 CFR 59.3)

State and local governments often obtain grants through the Land and Water Conservation Fund Act (LWCFA) to acquire or make improvements to parks and recreation areas. Section 6(f) of this act prohibits the conversion of property acquired or developed with these grants uses other than public outdoor recreation without the approval of the Department of the Interior's (DOI) National Park Service (NPS). DOI has delegated most review, consultation and assessment of Section 6(f) impacts and conversions to specified state recreation offices. When acquisition is required, Section 6(f) directs DOI to assure that replacement lands of at least equal fair market value and of reasonably equivalent usefulness and location are provided as a condition of such conversions. Consequently, where conversions of Section 6(f) lands are proposed for highway projects, replacement lands are required.


Because it is not uncommon for recreational properties to receive the LWCFA funding, Section 6(f) may be an integral part of Section 4(f) when recreational properties are involved. When dealing with Section 4(f) parks and recreation areas, it is critical to determine if the properties were acquired or improved with the LWCFA funds, and if so, the specifics of the improvements or property acquisition.


While Section 6(f) is similar to the recreation-related provisions of Section 4(f), there are some key differences:

  • Whereas Section 4(f) applies only to programs and policies undertaken by the U.S. DOT, Section 6(f) applies to programs and policies of any federal agency.
  • Mitigation opportunities are more flexible under Section 4(f) and may or may not include replacement lands. Section 6(f) directs the NPS to assure that replacement lands are of equal value, location and usefulness as impacted lands.

For a quick comparison of Sections 4(f), 106 and 6(f), see the comparison chart. view comparison chart