Report quantifying ecosystem benefits of green infrastructure with focus on social and economic benefits.
(2010) Published by the City of Portland Environmental Services. Portland’s average annual rainfall generates approximately ten billion gallons of stormwater runoff. As an alternative to traditional grey infrastructure that moves stormwater from the point of collection to a centralized treatment area, the approach of the Portland Bureau of Environmental Services (BES) is to increasingly manage stormwater where the rain falls with facilities that work like natural systems.
The purpose of this project is to provide an expert review of existing data and to quantify (to the extent possible) key ecosystem benefits associated with each gray to green best management practice (BMP), focusing on the “other benefits” categories that are more social and economic in nature. The project identifies categories of benefits, develops metrics (or representative indicators), and measures the relative benefit contribution of each BMP. The study is not intended to present a complete summary of benefits, but rather to identify and quantify metrics that indicate overall benefit. Recognizing that comprehensive information may not be available regarding the benefits of each BMP, the study identifies data gaps, areas of further research, and strategies to reduce uncertainty regarding benefit estimation. To the extent possible, benefits are estimated quantitatively but are also described qualitatively as necessary.