Contents lists available at ScienceDirect Environmental Impact Assessment Review journal homepage: www.elsevier.com/locate/eiar Hierarchy of factors affecting the social perception of dam reservoirs Danuta Piróg a , Joanna Fidelus-Orzechowska a, ⁎ , Łukasz Wiejaczka b , Adam Łajczak a a Institute of Geography, Pedagogical University of Cracow, ul. Podchorążych 2, 30-084 Cracow, Poland b Polish Academy of Sciences, Institute of Geography and Spatial Organization, ul. św. Jana 22, 31-018 Cracow, Poland ARTICLE INFO Keywords: Dam project Principal component analysis (PCA) Social perception Questionnaire survey Polish Carpathian Mountains ABSTRACT This study presents an assessment of factors that influence how people who live in the vicinity of dams view such projects. The usefulness of the principal component analysis (PCA) method for identifying variables that de- termine individuals' opinion about large dam projects was reviewed. The study focuses on people affected by the construction of the Mucharski Reservoir in the Polish Carpathians. The construction took over 30 years and took place at a time when Poland transitioned from a planned economy to a free market one. We used in-depth interviews (N = 96) and a set of 18 factors classified as personal, emotional and economic. Our results indicate that the variables that significantly affect social perception of dam projects by the local population include their opinion regarding the viability of the project, sense of security, personal benefits, the extent to which they have accepted the structure, respecting the local community's interests when drafting the development plans and new opportunities. The results allow for the future optimization of research tools used to comprehensively examine social perception of hydraulic structures. Using PCA allowed us to take semi-struc- tured data from interviews and extract meaningful relationships between the various inputs, show correlations between seemingly unrelated data, as well as explain the variances within the studied population. It also shows that PCA can be a useful tool for analyzing data that is not formally structured. 1. Introduction Dam reservoirs, besides their environmental impact, also affect the local population (e.g. Cernea, 1997; Warner, 1999; Sadler et al., 2000; Égré and Senécal, 2003; Beck et al., 2012; Scudder, 2012; Urban et al., 2013; Alrajoula et al., 2016; Cooke et al., 2017). According to the World Commission on Dams (WCD, 2000) the creation of reservoirs brings, on the one hand, certain social benefits and, on the other, a multitude of possible disadvantages for the local population. The scale and scope of those impacts depend, among others, on the size of the dam, its location and population density in the surrounding area. Research projects on the social perception of dams and reservoirs have been conducted since the 1960s (Kirchherr et al., 2016). It is important to study such topics in order to develop solutions that will reduce social costs and maximize benefits related to dam projects (e.g. Castelán, 2002; Chen et al., 2016). Kirchherr et al. (2016) have estab- lished that 93–95% of academic papers on social perception of dams indicate at least one negative social aspect of such projects. On the other hand, only 5–6% of studies illustrate the positive social impact of dams. Local communities can view reservoirs positively for instance in cases when they received satisfactory compensation for lost property or when they see new prospects for improving their quality of life (among others: Manatunge and Takesada, 2013; Sisinggih et al., 2013; Sivongxay et al., 2017). Malek Hosayni et al. (2017) state that dam construction can improve the economic situation of the region, enhance subjective well-being, and facilitate new forms of cooperation among local residents. Wiejaczka et al. (2014) have shown that the local people can be happy to live near reservoirs when they recognize their positive impacts and have a full sense of security. Despite the fact that there is an increase in literature on the social perception of reservoirs and dams, there are still many under-re- searched areas around this complex issue and they require further in- vestigation (Kirchherr et al., 2016). The publications on social impact of dams are particularly focused on resettlement issues (e.g. Bartolomé et al., 2000; Scudder, 2012). The studies to a lesser extent deal with the impact of dams on local people who were not subject to resettlement and need to live in close proximity to large dams. One of the key matters addressed in academic papers is the identification of factors that have an impact on how dams and reservoirs are viewed (e.g. Bird, 2012; Siciliano et al., 2015; Kirchherr et al., 2016). The studies con- ducted to date indicate that key factors that determine people's opinions about dams are economic, in particular, compensation for lost property https://doi.org/10.1016/j.eiar.2019.106301 Received 5 May 2019; Received in revised form 8 August 2019; Accepted 9 August 2019 ⁎ Corresponding author at: ul. Podchorążych 2, 30-084 Cracow, Poland. E-mail addresses: dbutryn@up.krakow.pl (D. Piróg), jfidelus@up.krakow.pl (J. Fidelus-Orzechowska), wieja@zg.pan.krakow.pl (Ł. Wiejaczka), alajczak@up.krakow.pl (A. Łajczak). Environmental Impact Assessment Review 79 (2019) 106301 0195-9255/ © 2019 Elsevier Inc. All rights reserved. T