Developing a green infrastructure equity index to promote equity planning

The Philadelphia Water Department has committed to taking a green infrastructure (GI) approach to reduce stormwater runoff and prevent combined sewer overflow events. Promoting GI as a stormwater management technique in a city necessitates development of a more distributed urban environmental management system, through which the city's water department needs to coordinate with a wide range of public and private stakeholders, shifting power from the utility to these other stakeholders. We argue that distributed urban environmental management can lead to more inclusive outcomes but only if there is an intentionality about how funds are distributed, which communities are prioritized, how partners are chosen and cultivated, and which types of projects are implemented in which neighborhoods. We suggest the development of an equity index to help identify communities that would most benefit from GI investment as critical for equitable GI planning. Using Philadelphia as a test case, we develop a Green Infrastructure Equity Index, designed with the indirect benefits of green infrastructure in mind, to determine which communities could benefit the most from investment in GI based on their “equity void ranking”. We argue that developing a GI Equity Index provides a much more nuanced analysis of communities that takes into account the built environment as well as the underlying social and economic conditions. The GI Equity Index also allows for a shift in the way we define equity. In doing so, it (1) changes the conversation about equity in GI planning using careful data analysis that takes into account both socio-economic and built environment variables; (2) provides a visual tool that communities can use to understand underlying conditions and the existing placement of GI; and (3) serves as a framework that can be tailored to allow communities to weight their priorities, putting more power in their hands.