Analysis of Socio-Economic Criteria for Sewage Siting Decisions: A Fuzzy DEMATEL Approach

Sewage treatment plants play a pivotal role in urban management because of the volume of waste generated. Hence, their siting must be given adequate attention to optimise its benefits to a community. This siting problem is complex when multiple socio-economic factors are considered. To address this problem, this study presents a parametric analysis method for sewage facility siting. The technique combines fuzzy logic and the DEMATEL (Decision-Making Trial and Evaluation Laboratory) method; this combination improved the handling of uncertainty associated with experts' opinions on the criteria assessment. This method was used to model and evaluate the relationship among different socio-economic parameters that affect sewage facility siting, including population density and proximity to residential areas. With this method, the current study determined the cause-and-effect relationships among the socio-economic criteria. Using information from an estate in Lagos, Nigeria, we observed that environmental sustainability and health impacts were the most significant criteria for siting sewage facilities. On the other hand, it was observed that economic development and residential areas were considered dependent variables – which implies that they are affected by different parameters. They were highly influenced by other socio-economic factors such as population density and proximity to residential areas. These findings show the importance of considering socio-economic factors in planning sewage facility siting to promote sustainable urban development while minimising a facility's socio-economic impact. The framework presented in this study provides urban planners with a systematic approach for optimising sewage siting decisions in urban communities.