Eco-Hydrology and Hydraulics of Urban Watersheds-A Resilience Approach

摘要

Urban water system managers face a set of interrelated water security challenges as they pursue the goals of sustainable sources of water, mitigating flood hazards, and improving water quality. These challenges are often subject to change (and hence highly uncertain) due to the coupled effects of hydro-climatic variability, socio-economic trends, and regulatory reforms. To meet these intersecting goals, we present a mechanistic framework with illustrative examples that evaluates an urban water system's resilience under future uncertainty. By employing principles from engineering design, ecosystem science, and social equity studies, our resilient urban water systems (ReUWS) framework explores the potential of effectively combining green and gray infrastructure (GGI) in an urban watershed while prioritizing stakeholder and community engagement throughout the lifecycle of water system projects. A nested set of hydrology, ecosystem, and hydraulic models are developed with data flow among them defining the boundary and initial conditions for each other. An example is shown with the Baltimore water system on an approach to evaluate the effects of GGI hybrids on major water security metrics. The corresponding engineering designs, ecosystem service potentials, and measures of equitable access to services are also analyzed using the framework. The results evaluate performance of the existing systems under future conditions and also compare different GGI-based strategies for improving resilience in urban water systems. The findings of the study help to evaluate the potential for using GGI strategies to cope with changing climate extremes and other environmental factors as well as social change. Trade-offs derived from the case studies also can be used to adjust local/regional policies and regulations.