Welcome to the Watershed Management Division's
Green Infrastructure Page

Green Infrastructure (GI) means different things to different people depending on the context in which it is used.  In Vermont we define it as “a wide range of multi-functional, natural and semi-natural landscape elements located within, around, and between developed areas at all spatial scales." Conservation areas, riparian buffers, greenspaces, detention ponds with vegetation, green roofs, bioswales, cisterns, permeable pavements and constructed wetlands are all considered GI.  Proper placement and maintenance of GI can result in many benefits such as increased human health and well-being, stormwater mitigation and improved water quality, increased property values and business revenues, decreased urban heat island effects, conservation of wildlife habitats and biodiversity, and provision of food for the urban population.  

Although GI is a relatively new term,  it's not an entirely new concept.  Its roots began in the planning and conservation efforts of the 1800’s.  It was later brought to the forefront in 1967 by Ian McHarg in his book “Design with Nature."  In the past few decades, GI has been recognized as an excellent tool for managing stormwater runoff.  This has resulted in a variety of GI Best Management Practices (BMPs) that are specifically focused on hydrology.  We refer to this subset of GI as Green Stormwater Infrastructure (GSI).  In 2011, the Green Infrastructure Roundtable defined GSI as "systems and practices that restore and maintain natural hydrologic processes in order to reduce the volume and water quality impacts of the built environment while providing multiple societal benefits."        

GSI has three main tenets: infiltration, evaporation, and  capture and re-use.  These three functions are utilized in a decentralized way throughout the landscape to manage stormwater as close to the source as possible.  This is in direct contrast to the more traditional Gray Infrastructure approach which uses centralized systems to direct water away from a site.