A critical evaluation of visibility analysis approaches for visual impact assessment (VIA) in the context of environmental impact assessment (EIA)

Dirk Cilliers, Michael Cloete, Alan Bond, Francois Retief, Reece Alberts, Claudine Roos

Research output: Contribution to journalArticlepeer-review

7 Citations (Scopus)


Visual impact assessment (VIA) concerns the identification and evaluation of the potential impacts that a proposed activity might have on the visual quality of a landscape and makes an important contribution to decision making in the environmental impact assessment (EIA) context. Visibility analysis is often used to assist in determining these impacts through a variety of approaches employing different techniques and data inputs. This paper identifies the visibility analysis approaches often used in VIA practice by reviewing a sample of VIA reports representing eleven (11) countries. The identified approaches were then evaluated for accuracy across differing landscapes through a total of 72 simulations. Analysis of variance was used to determine the sensitivity of the identified approaches to different variables within different landscape contexts. The type of digital elevation model (DEM) used was found to be the most significant variable affecting accuracy across all landscapes, while the technique used had some significance and resolution little significance.
Original languageEnglish
Article number106962
JournalEnvironmental Impact Assessment Review
Early online date22 Oct 2022
Publication statusPublished - Jan 2023


  • visual impact assessment
  • VIA
  • EIA
  • visibility analysis
  • viewshed
  • line of sight

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