Critical pathways of coupled human–water systems for understanding unintended consequences of human interventions

Water management interventions are designed to mitigate undesirable aspects of coupled human-water systems (CHWS). However, due to the nonlinear feedback mechanisms inherent in CHWS, these interventions sometimes lead to unintended consequences that exacerbate the very issues they aim to resolve. To develop a generalized understanding of the underlying mechanisms behind such unintended outcomes, this study conducts a meta-analysis of 37 case studies from around the world. We identified six core subsystems and defined a critical pathway showing how hydrological perturbations propagate in a CHWS and lead to unintended consequences of interventions. By analysing case storylines, we identified the critical pathways and harmonize them into prevalent critical pathways, which most frequently lead to unintended consequences for specific phenomena, together with the key variables. The results of this study can support more sustainable and resilient water management, as it is the critical pathways that must be altered to avoid unintended consequences.