Historically, urban stormwater management has relied on "gray" infrastructure—a network of pipes, ditches, and ponds designed to rapidly divert runoff from buildings and roadways. In contrast, green infrastructure seeks to manage stormwater at its source. By utilizing natural drainage pathways and Best Management Practices (BMPs), this approach reduces runoff and enhances soil infiltration, retaining moisture to support vital urban vegetation. This "living" infrastructure creates a feedback loop: healthy urban forests further reduce runoff while delivering a broad spectrum of environmental, economic, and public health benefits.
Despite these advantages, retrofitting an established city is a complex, costly endeavor. Transitioning from gray to green requires seamless interdisciplinary communication and a departure from centuries-old management paradigms.
To address these challenges, the Gray to Green (G2G) planning tool was developed. Central to the project's success is the application of ArcGIS, which provides the geospatial precision necessary for effective urban forest and infrastructure planning. To bridge the gap between complex spatial analysis and accessible data sharing, a custom ArcGIS add-on module was created. This module allows users to seamlessly export advanced statistics directly into Microsoft Excel for enhanced data visualization and reporting.
By empowering both technical and non-technical stakeholders, G2G demonstrates how green infrastructure can be integrated into existing or proposed developments. This paper details the research and data sources at the core of G2G—documenting all methods, equations, and assumptions to provide a fully transparent, peer-reviewed, and actionable planning framework.