The concept of resilience has been gradually getting more attention from both urban planners and researchers as our natural and human-based systems are facing increasing pressure. Green infrastructure (GI) is a mechanism used in urban planning and proposed to enhance urban resilience by providing services such as stormwater runoff attenuation, social and ecological benefits, and green employment. To understand the effects GI has on urban resilience, it is necessary to assess GI performance under the guise of urban resilience thinking. However, current literature lacks a comprehensive assessment framework combining quantitative and qualitative measurements to assess GI performance in promoting a social-ecological system resilience. We propose a Scenario-Based Planning Support System (SB-PSS) to help assess the contribution of GI to urban resilience. Building a robust indicator set incorporates quantitative and qualitative indicators using fuzzy comprehensive evaluation (FCE). Quantitative indicators are modeled, whereas qualitative indicators are surveyed; both types of data are used in the assessment of urban resilience. FCE transforms original measurements (quantitative and qualitative) into defined fuzzy membership degrees. Urban resilience capacity index is conducted to support decision-making for GI planning through scenario comparisons.
Results/Conclusions
Five scenarios were developed in the Congress Run sub-watershed of the Mill Creek watershed in Ohio, USA, to test common types of GI (rain barrels, rain gardens, detention basins, porous pavement, and open space) for their contribution to resilience. By our definition, open greenspace provides temporary storage of stormwater runoff and publicly-accessible recreation areas (e.g., picnic shelters, playground, etc.). The results show the open space scenario achieves the overall highest performance (GI Urban Resilience Index = 4.27/5). To implement the open space scenario in our urban demonstration site, suitable vacant lots could be converted to greenspace (e.g., forest, detention basins, and low-impact recreation areas). The benefit of SB-PSS is it allows public participation in the assessment process and incorporates users’ preferences and concerns in scenario generation. We propose a customizable SB-PSS and use widely-accepted indicators of resilience from the literature, making the methodology easy to duplicate, customize, and apply to other locations to assess environmental, economic, and social influence on urban resilience capacity for several types of GI.