Spatial Integration of Urban Runoff Modeling, Heat, and Social Vulnerability for Blue-Green Infrastructure Planning and Management

Abstract

Climate change exacerbates environmental challenges caused by urban growth. This study offers a multifaceted approach to understanding socioenvironmental vulnerability in cities by considering fine-scale spatial distribution of social and physical metrics overlaid with runoff and surface temperature (ST) data. Stormwater runoff depth and surface temperature data for micro-subbasins in Philadelphia were estimated and integrated to create an environmental vulnerability index. Social variables representing poverty, the elderly population, population density, and buildings with basements were used to develop a social vulnerability index. Simple analysis based on medians of combined environmental and social vulnerability indexes identified specific subbasins of the city that are most vulnerable to heat and flooding impacts of climate change. Hotspot analysis of combined social and environmental vulnerability data identified regions of the city that would benefit most from a focus on implementation of new green-blue infrastructures. Results indicated that neighborhoods in southern Philadelphia are most vulnerable to flooding and heat. The outlined approach can be used for any city, and provides city managers with a city-scale visualization for prioritizing areas in immediate need of climate mitigation practices.