Visual Effects Analysis

Visual Effects Analysis

The SHPO offers some guidance documents for defining visual effects for renewable energy or transmission line projects below.  This guidance is provided in accordance with the requirements of the National Historic Preservation Act of 1966, as amended (54 U.S.C. § 302303(b)(5)) to "advise and assist, as appropriate, Federal and State agencies and local governments in carrying out their historic preservation responsibilities". This section will be updated as time permits.

Recent ACHP guidance on the meaning of "direct" versus "indirect" effects can be found here. In March 2019, the D.C. circuit court issued an opinion that clarified the meaning of the term “directly” in Section 110(f) of the National Historic Preservation Act as referring to the causality, and not the physicality, of the effect to historic properties. This means that if the effect comes from the undertaking at the same time and place with no intervening cause, it is considered “direct” regardless of its specific type (e.g., visual, physical, auditory). “Indirect” effects to historic properties are those caused by the undertaking that are later in time or farther removed in distance but are still reasonably foreseeable (National Parks Conservation Association v. Todd T. Simonite) 

Agreement documents will be updated to reflect this opinion as time permits. 


Electric Transmission Visibility and Visual Contrast Threshold Distances in Western Landscapes

Guide to Evaluating Visual Impact Assessments for Renewable Energy Projects (Natural Resource Report NPS/ARD/NRR—2014/83)

Wyoming BLM Protocol Agreement, Appendix C Guidance on the Assessment of Setting

Possible Visual Effects distances based on these studies created by NV SHPO staff. 


Not Recommended:

The following document is not in compliance with the process identifed in the federal regulations implementing Section 106 of the NHPA found at 36 CFR Part 800 and its continued use is not recommended:

The Nevada SHPO does not recommend the use of the document titled Defining a Visual Area of Potential Effects to Historic Properties on BLM Lands in Nevada (Pay, 2020).  The conclusions found in the document are not based on an accurate understanding of how effects are determined under 36 CFR Part 800, the document contains significant errors of procedure related to the development of an APE, the document does not appear to have been developed with the assistance of individuals knowledgeable with the built environment or with other visual resource studies where the characterization of such effects are more common, its conclusions are not consistent with accepted literature or with the studies cited in the document, and it contains formulas and other methods for determining potential effects that are likely to be difficult for the public to understand.  These issues were identified in a letter from the Nevada SHPO dated June 18, 2021 and affirmed by the ACHP on April 28, 2022 and February 14, 2020.  To date, there have been no revisions to this document nor a response to these letters.   

All of the federal agency's districts in Nevada have been informed of the issues and the Nevada SHPO awaits the initiation of consultation and negotiation that will address the flaws and create a useful document that would support a reasonable and good faith identification effort.  Continued use of this document, whether it is policy or not, without adequate additional visual effects analysis and correction of its inherent flaws, cannot produce an APE that is either reasonable or prepared in good faith.  Any statements to the contrary are incorrect.