As a stormwater engineer, I have been asked if green infrastructure “really works.” This is because municipalities are starting to incorporate more green infrastructure into their master plans. After all, green infrastructure has the potential to provide multiple benefits to communities and the environment.
What is Green Infrastructure?
Green infrastructure refers to the use of natural or nature-based elements, such as vegetation, wetlands, permeable surfaces, and green roofs. In the past, many cities defaulted to concrete (“grey”) infrastructure due to the material’s durability. However, as the impacts of climate change begin to take hold on the world, cities are finding out that green infrastructure is a key component to building communities that will be resilient to the effects of climate change.
Benefits of Green Infrastructure
The benefits associated with green infrastructure are discussed in more detail below.
Stormwater Management
Green infrastructure techniques like rain gardens, bioswales, and permeable pavements help to capture and absorb rainwater, reducing stormwater runoff and the strain on traditional drainage systems. This helps to prevent flooding, decrease the pollution of water bodies, and recharge groundwater.
Urban Heat Island Mitigation
Green infrastructure elements like street trees, green roofs, and urban parks can help cool urban areas by providing shade, reducing the absorption and reflection of heat, and promoting evaporative cooling. This helps to mitigate the urban heat island effect, lower ambient temperatures, and improve the comfort of urban environments.
Biodiversity and Habitat Conservation
Incorporating green spaces and natural habitats within urban areas provides important refuges for biodiversity, supporting native plants, insects, birds, and other wildlife. Green infrastructure can help conserve and enhance local ecosystems, promote ecological resilience, and contribute to overall biodiversity conservation efforts. Incorporating native plants into green infrastructure enhances the habitat benefits associated with green infrastructure. This is because native plants provide food and shelter to pollinators. This is important because pollinators are crucial to ensuring a secure food supply. According to the United States Department of Agriculture, over 80% of the crops grown for food and industrial products require pollination by animals. Unfortunately, many of the pollinator species we rely on for food production in the United States are endangered or even close to extinction. Incorporating native vegetation into green infrastructure is one step to ensuring the continued survival of these important creatures.
Air and Water Quality Improvement
Vegetation and green spaces help to filter pollutants from the air, reducing the levels of harmful substances and improving air quality. Similarly, green infrastructure elements can help filter and purify stormwater, removing contaminants and reducing water pollution before it reaches natural water bodies.
Aesthetic and Community Benefits
Green infrastructure enhances the aesthetic appeal of urban areas, making them more visually pleasing and attractive. Access to green spaces and nature has been shown to have positive impacts on mental health and well-being, promoting relaxation, stress reduction, and increased physical activity. It also provides opportunities for recreational activities and community gatherings, fostering social cohesion.
Conclusion
So does green infrastructure work? Another way to phrase this question is “Does green infrastructure deliver on its promise to provide the benefits listed above?” The answer to this question depends on many factors including the quality of the design and construction, maintenance, and how people interact with these features. In my experience, maintenance is crucial to ensuring that green infrastructure continues to remain effective. Unfortunately, many landscaped features that function as drainage infrastructure are treated like any other landscaped area. I think this is because, after a while, people don’t know (or forget) about the function associated with these features. This is why I believe it is important to develop effective inspection and maintenance protocols. Another way to extend the life of green infrastructure is to get the surrounding neighborhood involved in the maintenance of green infrastructure. This gives people some ownership.
In summary, successful green infrastructure projects often require careful planning, integration into urban design, community engagement, and ongoing management to ensure long-term benefits.