Embracing complexity: Dynamics governing urban drinking water supply security in Mexico City

Abstract: Drinking water supply insecurity is globally on the rise, and prevalent in most low and middle-income urban areas. Multiple responses have emerged to cope with the lack of a reliable and equitable supply of safe and sufficient drinking water in cities, which presents a wide range of social-ecological implications. Yet, many of the analyses to date are focused on predominantly technological, ecological, and economic perspectives, overlooking broader cultural and political dimensions. What are the elements and the interrelationship between them that sustain the lack of drinking water supply security at an urban scale? The empirical case study is located in Mexico City, the capital city of one of the most drinking water-insecure countries globally and among the world’s five largest metropolitan areas. Qualitative data is elicited from a literature review and semi-structured interviews with key experts and urban stakeholders. The results provide an integrated understanding of the proposed system structure that created and maintain the water supply problem in the long-term. Hindrances include knowledge lock-ins and critical dynamics that inhibit the political support to transition towards a drinking water security scenario. This study shows that drinking water supply crisis in the study area and other cities with similar conditions need to be understood as multi-dimensional and from a system perspective, by challenging underlying assumptions and embracing interconnectedness. Key feedback mechanisms are presented in causal loop diagrams, allowing the exploration of higher-order leverage points to reduce existing path-dependencies as one increasingly important research area, and potentially relevant for decision-makers.