Resources, Conservation and Recycling 76 (2013) 27–40 Contents lists available at SciVerse ScienceDirect Resources, Conservation and Recycling journal h om epa ge: www.elsevier.com/locate/resconrec Influence of interventions and internal motivation on Swedish homeowners’ change of on-site sewage systems Are Wallin a,∗ , Mathias Zannakis b , Lars-Olof Johansson c , Sverker Molander a a Environmental Systems Analysis, Department of Energy and Environment, Chalmers University of Technology, SE-41296 Göteborg, Sweden b Department of Political Science, University of Gothenburg, Box 700, SE-40530 Göteborg, Sweden c Department of Psychology, University of Gothenburg, Box 500, SE-40530 Göteborg, Sweden a r t i c l e i n f o Article history: Received 30 March 2012 Received in revised form 14 April 2013 Accepted 19 April 2013 Keywords: Small-scale wastewater treatment Eutrophication Goal-framing theory Regulatory compliance Principal component analysis Multiple regression analysis a b s t r a c t This article reports results from a questionnaire administered to Swedish homeowners (N = 1481) investigating factors that influence them, as users and owners of on-site sewage systems (OSS), to envi- ronmentally improve their OSS. Social and psychological factors were based on previous research into pro-environmental and compliance behaviors and a previous interview study. The results suggest that the most important motives are to benefit, to act when outcomes are fair, and to avoid inconvenience. Less important motives are to act when outcomes are fair and to act of concern for the environment. Perceived efficacy in decreasing the environmental impacts of current OSS, when the OSS is changed, and perceived ability to change their OSS are also among the strongest predictors of readiness to change OSS. However, among homeowners who changed their OSS to do ones duty and achieve long-term safety were ranked highest. The results support the expectations of goal-framing theory that motives related to “gain” would be focal in situations of unfavorable cost–benefit ratios. Similarly, the importance of fair outcomes and efficacious rules is consistent with general findings in research on social dilemmas. © 2013 Elsevier B.V. All rights reserved. 1. Introduction What encourages homeowners to environmentally improve their on-site sewage systems (OSS)? The answer to this is very important for the efforts for reducing nutrient loads, mainly phos- phorous and nitrogen, to the marine environment. The costs of improving or changing OSS, which can be relatively high, fall on the individual homeowner, who only rarely receives any eco- nomic paybacks. Although there are rules and standards for OSS, enforcement by the authorities is inconsistent, offering homeown- ers the opportunity to avoid making environmentally necessary changes. The general aim of this study was to investigate which factors influence Swedish homeowners to decide to improve their OSS. We analyzed the role of various motives on deci- sions about changing their OSS under current policy and management regime, and went some way to analyze the effectiveness of current regulations and enforcement actions. ∗ Corresponding author at: Environmental Systems Analysis, Chalmers University of Technology, SE-41296 Göteborg, Sweden. Tel.: +46 31 772 5644; fax: +46 31 772 2172. E-mail addresses: are.wallin@chalmers.se, are.wallin@gmail.com (A. Wallin), mathias.zannakis@pol.gu.se (M. Zannakis), lars-olof.johansson@psy.gu.se (L.-O. Johansson). Knowledge of these factors will provide insight into increasing the effectiveness of current policy and management mea- sures. In this paper, we analyze the results of a questionnaire sent to a random sample of homeowners with OSS listed in the Swedish property registry. As dependent variables we measured whether respondents had changed their OSS, and their readiness to change in the short and long term. Respondents who had changed OSS were asked about the importance of various motivational and con- textual factors, interventions, and information sources to their decision to change OSS. To explain readiness to change OSS we tested factors derived from goal-framing theory (Lindenberg and Steg, 2007; Steg and Vlek, 2009), literature on compliance with government regulations (May and Winter, 1999; Winter and May, 2001; May, 2005), and studies of trust and fair institutions (e.g., Braithwaite and Levi, 1998; Levi and Stoker, 2000; Rothstein and Teorell, 2008). The paper is organized as follows: first, we present the background to the research; second, we briefly review relevant research into homeowners’ decisions to change to environmentally improved techniques and the motivational factors that underlie compliance behavior; third, we describe the factors tested in the study, the sampling procedure, and the items used in the ques- tionnaire; fourth, we present results from the data analysis. In the final sections, we discuss the results and draw some general conclusions. 0921-3449/$ – see front matter © 2013 Elsevier B.V. All rights reserved. http://dx.doi.org/10.1016/j.resconrec.2013.04.004