| dc.description.abstract | Urban water infrastructure systems are exposed to the impacts of various chronic and acute stressors such as climate change, population growth/decline, aging infrastructure, and extreme events (e.g., natural disasters). The ability and capacity of infrastructure systems to cope with the impacts of these stressors is characterized as resilience. Water utility agencies and infrastructure managers face significant challenges (due to deep uncertainty, funding constraints, lack of knowledge, etc.) to enhance the long-term resilience of their urban water infrastructure systems under the impacts of external stressors. To enable informed resilience planning and adaptation decisions, the present study adopted a complex system perspective to comprehensively assess the long-term resilience of water infrastructure systems. Through this perspective, different components of the complex water infrastructure system (i.e., physical infrastructures, human actors, external stressors) were captured, modeled, and analyzed using a simulation approach for theory development and exploratory assessment.
This research conducted four interrelated studies focused on both supply and demand sides of the water infrastructure resilience. As aging water distribution infrastructures near the end of their useful lifespan, first two studies focused on the resilience of water distribution systems. The first study established a framework to understand the long-term resilience of water distribution infrastructure systems based on performance regimes and tipping point behaviors under various scenarios of renewal strategies, funding levels, and population changes. The second study, examined the long-term performance of dual water distribution networks, as an alternative infrastructure solution proposed for improving the resilience of water distribution systems, in comparison with the conventional singular networks. The third study was prompted to deal with the impacts of climate change on coastal water supply infrastructures. This study specifically, evaluated the influence of adaptation decision-making processes of utility agencies on the long-term resilience of water supply systems under the impacts of sea-level rise and saltwater intrusion. Finally, the fourth study focused on the evaluation of demand-side solutions to enhance the resilience of urban water infrastructure systems, where due to population growth, climate change, and other factors making water scarcer, the supply-side solutions may no longer be sufficient. The last study particularly analyzed the underlying mechanisms affecting the adoption of water conservation technology by households to uncover the potential for residential water demand reduction.
Accordingly, four sets of important theoretical constructs related to long-term resilience of water infrastructure systems were identified from the analysis of simulated data: (i) the long-term performance regime of water distribution infrastructure system is shaped by its internal dynamics related to stressors-humans-infrastructure interactions; (ii) implementation of dual water distribution systems would improve the long-term performance (by decreasing water loss and energy loss by 28% and 80%, respectively) but with three times higher life-cycle costs; (iii) the state of nature (i.e., sea-level rise severity) is the most important determinant of coastal water supply infrastructure system resilience, regardless of the attributes of adaptation decisions; and (iv) households’ decision regarding the adoption of water conservation technology is driven mostly by income level and water pricing structure. The simulation results highlighted the importance and capabilities of the proposed frameworks in better understanding of water supply infrastructure system resilience. The insights of this research would also benefit water utilities, city planners, municipalities, and other stakeholders endeavoring to strengthen the resilience performance of water infrastructure systems. Progress in this domain improves the overall resilience of communities’ infrastructure systems to normal wear-and-tear and natural disasters alike. | en |
