Illinois Groundwork: GSI Case Studies

Explore a network of selected exemplary Green Stormwater Infrastructure

Illinois Groundwork

Reviewing case studies is important in understanding the wide-reaching impacts a GSI design can offer. Education and innovation are gained by exploring sites with exemplary GSI, leading to a more informed project, likely with more successful outcomes.

The following case studies provide examples of GSI at various scales and community contexts. The case studies were conducted by landscape architecture academics, professionals, and students through the Landscape Performance - Series Case Study Investigation research program, hosted by the Landscape Architecture Foundation (LAF). LAF is an organization dedicated to demonstrating the multiple values and benefits of green infrastructure. Explore each to gain insight into successful designs and installations.

Red Oak Rain Garden

Uptown Normal Circle

Morton Arboretum Permeable Main Parking Lot

Sarah E. Goode STEM Academy

Middle Blue River Basin Green Solutions Pilot Project

Sidwell Friends Middle School

Bagby Street Reconstruction

Red Oak Rain Garden

Urbana, Illinois

The Red Oak Rain Garden in Urbana, Illinois is a large public rain garden located on a 50,000+ student campus in a 40,000+ residential community. Historically, the area surrounding the rain garden site was a wetland, which, as a result of development, began to experience flooding after heavy rain events. The 10,000 square foot rain garden captures stormwater runoff from approximately 1 acre of parking lots, lawns, and sidewalks. It is designed to absorb up to 27,000 gallons of stormwater, the equivalent of a 25-year storm.

Uptown Normal Circle

Normal, Illinois

The Uptown Circle roundabout solved traffic issues at a busy intersection in downtown Normal, Illinois by creating a large central plaza integrated with stormwater capture features with tremendous collection capacity. Stormwater (approximately 1.4-Mgallons) is collected from the surrounding streets (totaling 58,000-SF of surface area) using a bog filtration system, native plantings, underground structural cells for tree root support, underground sand and UV filters to cleanse stormwater, and a 75,000-gallon underground cistern that recycles unused stormwater for irrigation.

Morton Arboretum Permeable Main Parking Lot

Lisle, Illinois

The Morton Arboretum Permeable Main Parking Lot replaced a former degraded asphalt parking lot with an interlocking permeable paver system in tandem with a retention pond and wetland so that stormwater overflow is also integrated with local aquatic ecology. The permeable parking lot, completed in 2005, was the largest of its kind in the Midwest when it was installed. At 205,000-SF, the lot holds 477 cars and 11 bus spaces, infiltrates and collects rainwater through a 4’ subsurface gravel bed that stores and slows water, channels water through 38,936-SF of bioswales, and directs overflow to a final cleansing via the 7-acre wetland area within a restored lake system. Because a majority of visitors to the Arboretum park and walk through the high-performance parking lot to reach the Visitor Center, the site serves as a key sustainability education feature at the Arboretum.

Sarah E. Goode STEM Academy

Chicago, Illinois

Sarah E. Goode STEM Academy is a 17.2-acre former brownfield in Chicago transformed into a public school that features numerous athletic fields set within a landscape of educational native gardens that are all designed to collect, convey, store, and/or infiltrate stormwater on site. The site is a showcase of GSI features including an 8,600-SF biology garden, 8,700-SF of community vegetable gardens, 6,000-SF outdoor classroom/picnic area, 28,000-SF of rain gardens, 4,000-gallon cistern, geothermal field, permeable parking for 100 cars, and storage for 35 bicycles. 32,000-SF of extensive roof gardens cover 40% of the school building. The design collects over 300,000 gallons of stormwater in a single rain event. The site is designed to also function as a neighborhood park and recreation center and contains educational signage throughout the school grounds to educate visitors about the water cycle, native plants, and prairie ecosystems.

Middle Blue River Basin Green Solutions Pilot Project

Kansas City, Missouri

Middle Blue River Basin Green Solutions Pilot Project, located in a primarily dense residential area, is an example of neighborhood-scale GSI distributed throughout a community, including permeable pavement and multiple types of rain gardens in the street rights-of-way to intercept stormwater and reduce stormwater from entering the combined sewer system. Rain gardens include 28 curb extension rain gardens with underground water storage, two cascade rain gardens designed as terraced basins, and 36 biorentention rain gardens containing engineered soil with underground water storage. Together the rain gardens collect 360,000 gallons of stormwater, reducing peak runoff flow by 76% (9.2cfs) and peak volume by 36% (39,000 gallons) for a 1.4-in. storm event.

Sidwell Friends Middle School

Washington, DC

Sidwell Friends Middle School is a 9,000-SF courtyard that treats all stormwater and wastewater on-site through a terraced garden that also serves as an outdoor classroom and educational gathering space. Stormwater is captured through vegetated terraces, wetlands, swales, rain gardens, native plantings, and a habitat pond. A green roof filters approximately 22,000-gallons of rainwater into underground cisterns which is later pumped to the biology pond during summer months. The whole project collects 317,000-gallons of stormwater annually and reduces portable water use by about 8,500-gallons monthly through the use of treated wastewater in toilet flushing. The site design also used reclaimed materials, including 8,000 board feet of wood and 77.5-tons of stone for decking, walls, and stairs for the landscape design, by redirecting that material from entering landfills.

Bagby Street Reconstruction

Houston, Texas

Bagby Street Reconstruction is an example of a streetscape retrofit that transformed 12 blocks of roadway integrating GSI throughout while attending to block-by-block differences. The project uses consistent materials, planting, lighting, and signage to achieve high-performance design including: capturing up to 437,000 gallons and improving water quality of stormwater through streetscape rain gardens, reducing pavement temperatures in the summer months through tree shading over 70% of the street, and sequesting 7,800-lbs of atmospheric carbon and absorbs an additional 38,000-gallons of stormwater through the planting of 175 trees. The project also reduced carbon emissions in the construction process by 300 tons through the sourcing of concrete made with fly ash.