Developing EPA’s Green Infrastructure Permitting Compendium

When it rains, stormwater flows over impervious surfaces, carrying pollutants to waterways and sometimes causing flooding and erosion. Green infrastructure uses soil and vegetation to improve water quality and manage rainwater where it falls. Green infrastructure not only supports stormwater management but also provides many co-benefits to communities, including climate resiliency, habitat connectivity, public engagement opportunities, and improved air quality. Many stormwater permits throughout the country already require green infrastructure implementation. To encourage even greater adoption of permit language with green infrastructure requirements, the U.S. Environmental Protection Agency tasked ERG with developing a resource for communities and permit writers that showcases national examples of how green infrastructure can be included in permits and woven into stormwater management programs.

ERG’s project team reviewed numerous municipal separate storm sewer system (MS4) permits from every state to identify permits with green infrastructure language or requirements that could serve as examples and models for municipalities and permit writers. Our team then compiled this content into an easy-to-digest Compendium of MS4 Permitting Approaches organized by topic areas consistent across MS4s. The compendium presents different permitting approaches that encourage or require green infrastructure and includes permit excerpts and corresponding implementation examples showcasing the specific actions permittees took to comply with the written requirements. Permitting authorities and permittees interested in expanding the use of green infrastructure in their communities can leverage these excerpts and implementation examples as they develop their permits.