Where is the Evidence? A Global Systematic Review of Sanitation System Resilience

Despite sustained efforts over several decades, no region is projected to achieve universal sanitation access by 2030, according to international monitoring frameworks. Climate change is increasingly disrupting human and ecological systems, in turn deepening existing inequalities in access to essential services, including sanitation. Coupled with broader socio-economic and political dynamics, these pressures are expected to further widen the global sanitation service gap. Strengthening the resilience of sanitation systems to climate-related impacts represents a critical component of addressing this challenge. Building resilience requires an understanding of the attributes of sanitation systems and the adaptation actions across scales that contribute to their capacity to anticipate, withstand and recover from climate hazards. While existing scholarship has primarily examined the impacts of climate hazards on sanitation system performance, less attention has been given to resilience-building processes and practices. This systematic review is the first to synthesise the evidence on resilience in sanitation systems. It identifies twenty-seven (n=27) attributes and adaptation actions with potential to enhance resilience. However, with only seventeen (n=17) studies meeting the inclusion criteria and limited empirical evidence, substantial knowledge gaps remain. These findings underscore the urgent need for targeted research and the development of measurable indicators of climate resilience to inform international monitoring frameworks and guide effective adaptation strategies.