This paper describes a participatory deliberative planning methodology employed in Can Tho, Vietnam to assess sanitation infrastructure options for a new peri-urban area with an expected population of 278,000 people. The study compared four options across a range of scales from centralised to decentralised treatment systems, and also included an innovative resource recovery option with urine collection and reuse in local agriculture. The study was undertaken in close collaboration with the local water utility, a local university, and several city government departments. In the sustainability assessment process key city stakeholders ranked the four options against criteria in five areas: (i) technical and risk, (ii) social and health, (iii) environmental, (iv) economic and financial, (v) city future. Stakeholders were provided with detailed information about each option, including quantitative data such as costs and energy use, and qualitative data against areas such as social acceptability. The assessment made evident the trade-offs between these five areas, and after their prioritisation, stakeholders agreed on the option that combined centralised treatment for the densely populated area to be inhabited earlier, and decentralised treatment for the remaining area. The methodology provided a robust way for stakeholders to engage in informed decision-making on this important planning issue.
