NHPA: Assessing adverse effects to historic properties by your project

Once the Lead Federal Agency has identified that historic properties may be affected by your project,  then the next step is to assess adverse effects on the historic properties by your project.

Under §800.5, the Lead Federal Agency starts by applying the criteria of adverse effect in consultation with the SHPO/THPO and any Native American or Native Hawaiian organization that attaches religious and cultural significance to the historic properties.

What is the criteria of adverse effect?

If your undertaking or project may alter, directly or indirectly, any of the characteristics of a historic property that qualify the property for inclusion in the National Register of Historic Places, and as a result diminish the historical integrity of the property’s location, design, setting, materials, workmanship, feeling or association, your project meets the criteria for having an adverse effect on a historic property.

What are some examples of adverse effects?

Your undertaking or project will meet the criteria of adverse effect in the following types of situations:

  • Physical destruction of or damage to all or part of a historic property;
  • Physical alteration of a historic property that is not consistent with the Secretary of the Interior’s standards for the treatment of historic properties (36 CFR part 68), including:
    • restoration
    • rehabilitation
    • repair
    • maintenance
    • stabilization
    • hazardous material remediation, and
    • provision of ADA access;
  • Physical removal of the historic property from its historic location;
  • Change of the character of the historic property’s use or of physical features within the property’s setting that contribute to its historic significance;
  • Introduction of visual, atmospheric or audible elements that diminish the integrity of the historic property’s significant historic features;
  • Neglect of a historic property which causes its deterioration, except where such neglect and deterioration are recognized qualities of a property of religious and cultural significance to a Native American or Native Hawaiian organization; and
  • Transfer, lease or sale of a historic property out of Federal ownership or control without adequate and legally enforceable restrictions or conditions to ensure long-term preservation of the historic property’s significance.

How does assessing adverse affects to historic properties work?

Lastly, if no Historic Properties will be adversely affected by the Project or Undertaking, because the land developer was able to redesign their project to avoid adverse effects to historic properties, the Lead Federal Agency must provide notification of this finding to the SHPO, all consulting parties, and make the notification available for public inspection prior to approving your project or Undertaking.

If Historic Properties will be affected by the Project or Undertaking, because there are historic properties which may be affected by the Undertaking, the Lead Federal Agency must notify the SHPO and all consulting parties, invite their views on resolving the effects, and the next step is to resolve adverse effects, in accordance with §800.6.


The next few posts in this series will focus on the following:

4. Resolving adverse effects to historic properties by your project
5. Other Section 106 considerations