Green Infrastructure

Preserving and Enhancing Ecological Function through Design

We are used to thinking of infrastructure as built public works systems, such as roads, sewers, and utilities. “Green Infrastructure” is a relatively new term that requires us to think of our natural resource systems – woodlands, grasslands, wetlands, streams, parks, trails – as ecological infrastructure. Because these natural systems provide critical capacity and function, green infrastructure has become a vital part of sustainable community planning and design.

While the term is often used differently depending on the context, all definitions emphasize the principle of enhanced connectivity. In their book Green Infrastructure: Linking Landscapes and Communities, Mark Benedict and Edward McMahon define green infrastructure as an interconnected network of green space that conserves natural ecosystem functions and values, and provides associated benefits to both people and wildlife. These include groundwater infiltration, water quality, wildlife habitat, biodiversity, building soils, etc.

Some definitions focus on the stormwater side of green infrastructure, using or mimicking natural processes to infiltrate and reuse runoff on site. Others emphasize a natural system networking approach promoting habitat creation and biodiversity. SmithGroup emphasizes a broader application of green infrastructure, integrating natural systems function and air/water quality enhancement with improvements to a community’s transportation, recreation, food and energy networks.

The benefits of this expanded definition are particularly pronounced at the community planning level. Most green infrastructure plans include an identification of important “hubs,” larger areas of ecological significance connected by primary “links” or “corridors.” Linking to community transportation and recreation networks forges more connections within and between communities during the planning process. The result is broader buy-in and commitment for the creation and preservation of green infrastructure.