Green Stormwater Infrastructure
Green Stormwater Infrastructure (GSI) is an approach to managing stormwater in ways that mimic nature. It aims to capture water where it falls, preventing runoff from entering our storm sewer systems. GSI employs various tools that allow runoff to get soaked up by plants, filter into the ground, evaporate, or be stored for human use. GSI sees stormwater as a resource, not a nuisance.
Credit: City of Boston
Examples of Green Stormwater Infrastructure:
Rain Gardens
These are bowl-shaped gardens designed to capture and infiltrate stormwater. Rainwater and snowmelt from hard surfaces is channeled to the garden where it pools, filters through plant and other organic material, and soaks into the ground rather than running off and entering the storm sewer system.
Riparian Buffers
These areas are adjacent to a stream, lake, or wetland and contain a combination of trees, shrubs, and/or other perennial plants designed to filter pollutants from runoff before it enters the body of water. Buffers also shade streams, keeping water temperatures cooler which is essential for aquatic life to thrive.
Tree Planting
Trees are sponges for water and are a great asset to a yard for their water infiltration, shade, and wildlife benefits. A 45-inch-thick Northern red oak will intercept over 23,000 gallons of water per year! Long term success can be ensured by planting the right size tree for your space.
What are the benefits of green stormwater infrastructure?
Conserve Water and Save Money!
GSI additions like rain gardens and conservation landscapes can help save you money by decreasing the need for fertilizer and irrigation. Rainwater harvesting tools like rain barrels can also help reduce the amount of city water you need to use in tasks like watering your plants and washing your car.
Reduce Flooding
Did you know that flooding costs US communities approximately $32 billion annually? GSI can help prevent flooding by decreasing the volume of stormwater that enters our sewers and waterways. We all live in a watershed, and large amounts of stormwater runoff from communities upstream create flooding issues for communities downstream. Further, frequent floods damage stream habitat, making it hard for aquatic insects and fish to survive. ​​​
Decrease Pollution to Our Waterways
By infiltrating stormwater runoff, GSI also helps reduce water pollution by absorbing fertilizers, oil, heavy metals, sediment, and more. This preventative approach increases the quality of the waterways we rely on for drinking water and recreational activities like swimming and fishing.
Provide Habitat for Local Wildlife
Green stormwater infrastructure often incorporates native plants. These plants are important sources of food and shelter for various species of wildlife, including eye-catching insects like monarch butterflies and lightning bugs, songbirds like goldfinches and blue jays, and vital pollinators like bees and hummingbirds. Providing habitat for pollinators is imperative, considering that about 35% of the world’s food crops depend on pollination to produce. ​​
Beautify our Communities
GSI increases green spaces in our communities. According to the EPA, “Recent research has linked the presence of green space to reduced levels of inner-city crime and violence, a stronger sense of community, improved academic performance, and even reductions in the symptoms [of] attention deficit and hyperactivity disorders.” Increasing tree canopy in urban areas can also decrease extreme temperatures during heat waves and mitigate the heat island effect.