Multi-Criteria Decision Analysis for Wastewater Technology Selection in Developing Countries: Scenarios for Decentralized Systems in Thailand

Appropriate wastewater treatment option is not only a system providing the best performance at least cost, but is also sustainable in terms of meeting local needs—socio-cultural acceptability, technological and institutional feasibility, economical affordability, and environmental acceptability. This paper aims demonstrate an alternate approach for appropriate wastewater technology selection, which can consider local needs and incorporate the crucial local factors of developing countries into the selection process. Using suburban communities in Bangkok as case studies, the paper provides a systematic analysis of four wastewater treatment alternatives: activated sludge (AS), oxidation ditches (OD), aerated lagoons (AL), and waste stabilization ponds (WSP). The study uses multi-criteria decision analysis (MCDA) techniques for comparing and rank ordering wastewater treatment technology alternatives against the identified technical, socio-economic, and environmental objectives. The proposed wastewater treatment options obtained from the MDCA are analyzed with the local needs, availability of resource, and constraints before the most locally appropriate system is selected.