Abstract Sewage sludge is a by-product of wastewater treatment and has a complex composition including organic matter and nutrients. The recovery of the useful components can partially buffer the continuous depletion of natural resources. However, due to a range of many complex variables, such as concerns on safe-use practices and lack of technical capacities, sludge recovery is classified as a wicked problem. To facilitate the decision-making process, this study intends to provide a decision support framework (DSF) to guide decision making towards selecting sustainable options to handle sewage sludge in Latin America. The framework was tested and refined through a case study in Panajachel, Lake Atitlan, Guatemala. Sludge disposal solutions are missing in the municipality and the pathogen content highly exceeds national and international standards. The framework was used to evaluate possible recovery scenarios. The results show that the most sustainable ways to use sewage sludge in Panajachel are through agricultural use and soil conditioning. Composting is suggested as a conversion process to eliminate pathogens and obtain stable fertilisers.
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