Green Infrastructure and Clean Water Act Requirements Resources

The Evolution of Green Infrastructure for Clean Water Act Implementation

1972
Clean Water Act
The Clean Water Act (CWA) was enacted in 1972. Since then, EPA, states, and municipalities have made noteworthy progress on protecting our waters through implementing the CWA. In the years since its passage, the CWA created a voluntary pathway to use green infrastructure to treat stormwater, improve water quality, and mitigate flooding while beautifying our communities.

2007
Use of Green Infrastructure in NPDES Permits and Enforcement Under the Clean Water Act (pdf)
In 2007, EPA officially recognized green infrastructure as a stormwater control measure under the CWA and clarified how it can be used to meet existing CWA requirements. EPA also officially acknowledged the multiple benefits green infrastructure can provide communities.

2012–2017
EPA's Integrated Municipal Stormwater and Wastewater Planning Guidance
In 2012, EPA released guidance for consistent implementation to develop and implement effective integrated plans under the CWA. This framework encourages the use of green infrastructure.

2015
EPA Green Infrastructure Permitting and Enforcement Fact Sheet Series
In 2015, EPA released a fact sheet series that includes sample language and case studies on integrating green infrastructure concepts into permitting, enforcement, and water quality standards.

2019–2021
Water Infrastructure Improvement Act
In 2019, The Water Infrastructure Improvement Act amended the Clean Water Act to, among other things, require EPA to promote the use of green infrastructure and integrate it into "permitting and enforcement..., planning efforts, research, technical assistance, and funding guidance" (Clean Water Act §519). The act also added the definition of green infrastructure to the Clean Water Act (Clean Water Act §502).

Green Infrastructure Federal Collaborative
In 2021, EPA launched the Green Infrastructure Federal Collaborative. This EPA-led Federal Collaborative created a community of practice that aligns knowledge and facilitates coordinated strategies to foster climate resilience and encourage the equitable implementation of green infrastructure in all communities.

Policy Memos

EPA strongly encourages the use of green infrastructure approaches to manage wet weather. Since 2007, EPA's Office of Water has released the following policy memos that support integrating green infrastructure into National Pollutant Discharge Elimination System (NPDES) permits and combined sewer overflow (CSO) solutions.

• Achieving Water Quality through Integrated Municipal Stormwater and Wastewater Plans (pdf) (1.07 MB)
• Protecting Water Quality with Green Infrastructure in Water EPA Permitting and Enforcement Programs (pdf) (343.37 KB)
• Use of Green Infrastructure in NPDES Permits and Enforcement (pdf) (923.21 KB)
• Using Green Infrastructure To Protect Water Quality in Stormwater, CSO, Nonpoint Source and other Water Programs (pdf) (161.66 KB)
• Memorandum, Clarification on which Stormwater Infiltration Practices/Technologies Have the Potential To Be Regulated as "Class V" Wells by the Underground Injection Control (UIC) Program (pdf) (214.77 KB, 2008)

Green Infrastructure Permitting Enforcement Fact Sheet Series

The green infrastructure permitting and enforcement fact sheet series provides EPA and state permitting and enforcement professionals with a guide to integrating green infrastructure approaches into NPDES wet weather programs. The series consists of fact sheets and supplements on integrating green infrastructure concepts into permitting, enforcement, and water quality standards actions. The series includes sample language and case studies to illustrate the concepts presented.

• Fact Sheet 1: General Accountability Considerations for Green Infrastructure (pdf) (2.01 MB)
• Fact Sheet 2: Combined Sewer Overflows (pdf) (2.94 MB)
• Fact Sheet 3: Sanitary Sewer Overflows (pdf) (1.25 MB)
• Fact Sheet 4: Stormwater (pdf) (1.32 MB)
• Fact Sheet 5: Total Maximum Daily Loads (pdf) (1.91 MB)
• Fact Sheet 6: Water Quality Standards (pdf) (1.28 MB)
• Supplement 1: Consent Decrees that Include Green Infrastructure Provisions (pdf) (2.33 MB)
• Supplement 2: Consent Decree Language Addressing Green for Gray Substitutions (pdf) (4.43 MB)
• Supplement 3: Green Infrastructure Models and Calculators (pdf) (1.19 MB)
• Supplement 4: Green Infrastructure in Total Maximum Daily Loads (pdf) (1.82 MB)