Due to the population growth and urbanization’s trend, peri-urban areas that surround major cities are haphazardly increasing without proper infrastructure in the developing world. Even though the literature review points out that there are several suitable wastewater treatment system (WWTS) alternatives which could mitigate that issue, one of the main problems lies on the process of making decisions. Thus, this study applies the Structured Decision Making (SDM) instrument through the use of a particular tool for supporting the evaluation. In this view, the ValueCharts is a user-friendly tool that can easier narrow down comparable Overall multi-attributes values, mainly obtained from the performances and preferences given by participants of the decision. The outcomes from the cited tool’s application have indicated the propensity to succeed WWTS alternatives that bear efficient processes in terms of environmental removals indicators.