Beneath the surface - Chicago Reader

After a storm, Chicago streets transform. Water rushes through alleys and basements begin to seep. The sewers can’t drink it all, so if the water doesn’t back up into basements, it spills into the river.

Even a light rain creates puddles that swallow curbs, because the infrastructure’s job is to protect us from sewage flooding, not to keep our streets dry. Chicago uses two key systems to reduce sewage flooding: the Deep Tunnel and restrictor valves. The massive Deep Tunnel system holds billions of gallons of stormwater and sewage. It keeps this water out of streets and basements until it can be treated.

Restrictor valves, placed in storm drains, slow the flow of rainwater into sewers so the system isn’t overwhelmed, causing that leftover water to pool in the streets. With much of the city covered in turf or concrete, the additional stormwater has nowhere to go.

When a heavy downpour causes flooding, the costs add up fast. From 2007 to 2011, Cook County residents filed over 181,000 flood claims. The Center for Neighborhood Technology (CNT) reported that these claims totaled $773 million. Out of 100 households that CNT surveyed, 70 percent of respondents reported flooding three or more times in those five years.

Green infrastructure, like native gardens, pathways, and soil systems, absorbs rainwater where it falls. Instead of overwhelming the sewers, water sinks into the ground, nourishing plants. And those plants can be beautiful, too. Imagine pollinator gardens filled with native flowers that attract butterflies and bees.

That’s the solution Janice Horwich and Joanne Yonan brought to Lakeview’s Graceland West neighborhood. They had tried green infrastructure in their own yards and were ready to expand it to their whole neighborhood. In 2014, as members of the Graceland West Community Association (GWCA), they launched an environmental committee with the goal of tackling two problems at once: flooding and habitat loss.

Sky Rodriguez

The committee’s first project, installed in 2015, was small: a 100-square-foot patch of native plants. They designed it for both pollinators and stormwater absorption. Soon after, CNT connected them with then Aurora mayor Tom Weisner. Aurora has been investing in green infrastructure since 2010. It started with rain gardens, bioswales, and biofiltration basins by Spring Street and RiverEdge Park. These features use native plants and permeable soils to capture stormwater. Weisner gave them a tour of the town’s extensive stormwater solutions. He taught them to hold water by building a nine-inch layer of soil made from compost and coconut coir, and urged them to plant native species.

They took the advice word for word. Working with soil experts, they also added mycorrhizal fungi inoculants, which form an underground network that helps plants’ roots pull in even more water. “Grass is almost as bad as cement,” says Sybil Derrible, a professor at the University of Illinois Chicago who studies sustainable and resilient infrastructure. “Native plants have deeper roots and maximize the void space in the soil. That’s what makes the system work.”

Streets with pollinator plots flood less because the rain has somewhere to go. “When deployed in large numbers, they can have a significant impact,” Derrible says. But he cautions that the details matter—soil depth, shape, and plant choice can make or break the system.

Since that first plot, the committee has installed 17 sites across the neighborhood. Many are on intersection corners, in driveways, and around schools. Most are about 100 square feet and cost around $200, paid for through donations and association memberships. It takes GWCA one to three days to put one in, depending on how much turf or concrete they have to remove. According to CNT, a typical 100-square-foot site absorbs more than 2,000 gallons of water a year.

In their first year, the sites need watering and a simple fence for protection. But once established, they’re hardy. Because the plants are native, they can also handle Chicago winters; mountain mint, milkweed, black-eyed Susans, goldenrod, and purple coneflowers come back every year. They grow deep roots and attract butterflies, birds, and essential pollinators, including the endangered rusty patched bumblebee.

Sky Rodriguez

The benefits go beyond flood control. The pathways cool the air, boost biodiversity, and add color and life to walks. “Everybody is capable of doing this,” Yonan says. Swapping concrete and turf for native plants is simple, sustainable, and low-cost.

Some citywide initiatives have been built to incrementally pursue this work. The Metropolitan Water Reclamation District has funded projects like rain gardens, green roofs, bioswales, and permeable pavement. Conservation organizations like Openlands have worked with different city departments on growing green spaces around the city. But still, the real momentum is building neighborhood by neighborhood, block by block, with groups like GWCA, Calumet Stormwater Collaborative, and the Little Village Environmental Justice Organization.

Neighbors are noticing the difference and joining in the efforts. In Graceland West, families help plant community spaces and are replacing their own lawns and concrete driveways with native gardens. Even schools, landlords, and homeowners are donating space, money, and labor. This fall, GWCA will add ten more sites around the neighborhood. “We’re fighting back to show how we can improve our environment in a low-cost and sustainable way,” Yonan says. “Because it’s right, someone had to do it,” Horwich adds.