Welcome to Environmental Minute! I’m your host, Maddie Yang.
Today we are diving into green infrastructure. Let me pose a question. What if cities were created to work like forests - functioning with nature instead of against it…
A lot of times when people think of cities, they think of concrete, smoke, pollution, tight traffic, skyscrapers, and a constant buzz from day to night. The complete opposite of a serene forest, with abundant green, trees, fungi, fresh air, and a sense of calm.
But it doesn’t have to be exactly like this. And this is where the idea of green infrastructure sprouts from - it’s a growing movement to design cities that mimic natural systems. As opposed to treating water, heat, and pollution as problems to combat, green infrastructure looks at how forests, wetlands, and prairies manage these challenges - and then applies them to urban life.
Let’s first look at trees.
A single, fully mature tree can intercept thousands of gallons of stormwater per year, filter air pollutants, provide shade, cool temperatures, and support biodiversity, providing vital resources for a city that lacks in those areas.
But green infrastructure goes way beyond planting trees. A great example of green infrastructure is the green roof - a living layer of soil and plants built on top of a building. In nature, plants absorb rainfall, snow runoff, and store water, and a green roof can do the exact same! Green roofs can reduce flooding, insulate buildings, cut back on energy use, and create mini habitats in the middle of skylines. Actually in places like Chicago and Toronto, green roofs have become so widespread that they create their own cooling effect.
Another example is the rain garden - a shallow planted basin designed to capture runoff from roofs, sidewalks, or parking lots. Instead of allowing water to collect directly in storm drains and overwhelm sewer systems, a rain garden slows this process down and lets the soil and plants filter it naturally, just like a forest floor would do after a storm. Cities like Seattle and Philadelphia have installed thousands of these gardens, transforming neighborhoods and reducing flooding.
And then there are bioswales, which may be a little more difficult to decode exactly what it is. A bioswale functions like a mini riverbank, channeling storm water through vegetated, soil-filled trenches where sediment settles and pollutants are absorbed. It’s actually the same process that happens in natural floodplains and streamside habitats, just recreated along roads, transit stations, or parking lots.
As you can see from these three examples, a lot of green infrastructure is similar to biomimicry, which if you’re unfamiliar with what that is, you should go check out the last episode of Environmental Minute. A lot of it is about restoring nature’s original water cycle, as healthy ecosystems allow rainwater to soak into the ground, recharge aquifers, support wetlands, and feed streams slowly over time, whereas traditional cities built from concrete and asphalt interrupt this cycle, allowing water to rush across pavement, pick up pollutants and flood into drains.
You can see green infrastructure allowing this transformation to take place around the world. In Singapore, lush “supertrees,” sky gardens, and planted skyscrapers blur the line between city and ecosystem. In Copenhagen, redesigned parks and plazas double as stormwater basins, capturing floods during extreme rainfall. In New York City, the “Million Trees” initiative and expanding greenways are turning the city into a cooler, more connected urban forest. And in Los Angeles, concrete canals are being reimagined into greener, more natural river corridors.
However, what I think the most important part of green infrastructure is how it changes the way we think about cities. Instead of drawing distinct lines between urban and rural, green and gray, forest and concrete jungle, green infrastructure aims to combine the two. It serves as a reminder that environmental solutions don’t always require new technology, and sometimes the best solutions already exist… in nature!
Thank you so much for tuning into this episode of Environmental Minute, and I hope this conversation has inspired you to think about the incredible field of green infrastructure and the potential it has to rethink the way we perceive cities. Until next time, I’m Maddie Yang, and this has been Environmental Minute.
