Under Section 106 of the National Historic Preservation Act, federal agencies, including the Federal Highway Administration (FHWA), must consider the effect of an undertaking on historic properties. For transportation undertakings, state departments of transportation (DOTs) frequently act as the federal agency representative and evaluate the effects on historic properties as part of the transportation project development process. DOTs must be equipped not only to make such evaluations but also to clearly communicate the findings to federal agencies, State Historic Preservation Officers (SHPOs), Tribal Historic Preservation Officers (THPOs), other consulting parties, and members of the public.  

Federal regulation (36 CFR 800.5) makes a distinction between undertakings that adversely affect historic properties and those that do not; the latter are referred to as no-effect and no-adverse-effect findings. The criteria for determining an adverse effect is well-defined in the regulations; however, adverse effect findings account for only a small percentage of the Section 106 determinations made each year. There is less information on findings of no-effect or no-adverse-effect to historic properties. Such cases are frequently encountered in connection with transportation projects. 

Drawing upon a reasonable and good-faith identification process, a well-reasoned and defensible determination that a transportation project will have no-effect or no-adverse-effect on a historic property requires thorough, working knowledge of:   

• Criteria and character-defining features making a property eligible for listing in the National Register of Historic Places; 
  
  
• Aspects of historic integrity that are important for a property to convey its significance;
  
  
• Section 106 regulations, particularly as they relate to criteria of adverse effect; 
  
  
• Resources available for use in the effects assessment process; and
  
  
• Interests of partners and stakeholders who participate in the effects review process and comment on the evaluation—including SHPOs, THPOs, consulting parties, members of the public—coupled with insights into their potential questions and concerns.

However, for a determination to be effectively communicated during the consultation process, this background knowledge must be coupled with the skill to clearly articulate the reasoning behind the findings and proactively address potential concerns, fostering trust with partners and stakeholders. Insufficiently justified determinations or those that rely on an outdated or incomplete identification can lead to delays in project development and permitting, impede efficiency in consultation, and provide a weakened administrative record of project development decisions.