New EPA Report Finds it Pays to Go Green (for Stormwater Management)

Green infrastructure can save cities millions of dollars, provide multiple environmental and social benefits

Lancaster Case Study 3.4.14CHICAGO, March 4, 2014 – “Green is good” is conventional wisdom for sustainability advocates. For municipal stormwater management, convention is typically a different color: gray. But a new report from the U.S. Environmental Protection Agency (EPA) could change all that.

The Economic Benefits of Green Infrastructure: A Case Study of Lancaster, PA offers real world evidence that green infrastructure (such as rain gardens, permeable pavement, and bioinfiltration installations) can be an effective, sustainable and budget-friendly approach to help manage stormwater in American communities.

The EPA case study builds on CNT’s groundbreaking guide, The Value of Green Infrastructure, to quantify the cost savings, social benefits, and environmental advantages of Lancaster’s Green Infrastructure Plan, developed in 2010 to enhance community sustainability and reduce the volume of stormwater runoff returned to local waterways.

Lancaster Case Study - MapUsing calculation methods outlined in CNT’s Guide, the EPA estimated that Lancaster’s Green Infrastructure Plan could cut capital costs for gray infrastructure by $120 million and reduce wastewater pumping and treatment costs by $661,000 per year. Additionally, approximately $4.2 million in annual energy, air quality, and climate-related benefits were projected for the Lancaster community.

“As thrilled as we are to see CNT’s research and methodologies in action, we are equally excited to see the City of Lancaster take such progressive action to help manage stormwater through green infrastructure,” said Danielle Gallet, CNT’s Water Supply Program Manager and Infrastructure Strategist, co-author of CNT’s The Value of Green Infrastructure guide, and consultant to the EPA on the Lancaster project. “This case study demonstrates that there are multiple bottom-line benefits to implementing natural solutions to environmental challenges.”

Along with the financial advantages identified using the Guide’s calculation methods, the EPA report also found that installing green infrastructure in Lancaster would provide noticeable social benefits that cannot readily be assigned dollar values. These include reduced urban heat island effect, increased property values, and new public education opportunities.

“CNT is a long-time advocate of localized, place-based approaches to improving the sustainability of cities,” said Kathryn Tholin, CEO of CNT. “We are pleased that the EPA and the City of Lancaster employed CNT’s green infrastructure valuation guide to quantify the economic and social rewards of the City’s Green Infrastructure Plan. We hope other communities across America will follow Lancaster’s lead.”

The EPA’s Lancaster case study follows CNT’s The Value of Green Infrastructure guide, which delves into the benefits of five green infrastructure practices in eight benefit categories to develop a generalized methodology for valuing the additional benefits of green infrastructure:

Evaluation Tool Graphic - Method for Valuing the Benefits of GI

For each green infrastructure practice and benefit category for which adequate research is available, the Guide presents a two-step process for valuing benefits:

Evaluation Tool Graphic - Valuation Steps in Action

CNT and American Rivers released The Value of Green Infrastructure in 2011 to provide municipalities with a methodology for assessing the financial, environmental and community benefits of select green infrastructure elements. By demonstrating that a comprehensive green infrastructure strategy can help reduce the economic burden of water management while improving a community’s quality of life, CNT helped establish green infrastructure as part of a viable planning solution to stormwater management.

Learn More:

The Economic Benefits of Green Infrastructure: A Case Study of Lancaster, PA (PDF)
EPA Press Release
Green Infrastructure Valuation Guide
Green Infrastructure Portfolio Standard (GIPS)
Green Values Stormwater Toolbox
CNT Demonstration Projects


Ryan Kilpatrick, Communications Director, CNT


The Center for Neighborhood Technology (CNT) is a Chicago-based, award-winning innovations laboratory for urban sustainability, founded in 1978. CNT shows urban communities across the country how to develop more sustainably and equitably. CNT promotes the better and more efficient use of the undervalued resources and inherent advantages of the built and natural systems that comprise the urban environment.