Stream Restoration is essential for managing urban waterways prone to erosion and flooding. In Downers Grove, Illinois, the Prentiss Creek Streambank Stabilization Project demonstrates how strategic ecological design can restore a waterway while safeguarding nearby neighborhoods. In 2023, A3 Environmental Consultants (A3E) – known as Olson Ecological Solutions at the time – teamed up with the Farnsworth Group and municipal officials to embark on a stream restoration effort focused on mitigating stormwater impacts, improving water quality, and enhancing habitat. Implementation of the project is planned for 2026.
Stream Restoration in Downers Grove
Prentiss Creek, flowing through a constrained corridor lined with residential neighborhoods and a school campus, suffers from severe erosion and bank failure due to excessive stormwater inflows. Stream Restoration in this context requires carefully balancing hydraulic control with ecological enhancement. The project was divided into two reaches. In the upper, intermittent section, the focus was on invasive species removal, native plantings, and low rock check structures with flow-through pipes. These structures temporarily detain stormwater, allowing sediment and pollutants to settle while maintaining flow and preventing standing water.
Downstream, where the creek becomes perennial and erosive forces increase, engineered rock structures such as J-hooks and cross-vanes are to be installed to create in-channel floodplain functionality. Native plantings integrated into these structures will enhance stability and provide habitat for pollinators and wildlife. Overall, this Stream Restoration effort demonstrates a balance of hydraulic performance, ecological restoration, and public perception, highlighting a sophisticated approach to urban waterway management.
Stream Restoration Process and Methodology Plans
The methodology applied during the Prentiss Creek Stream Restoration planning followed a combination of ASTM E1527-21 standards and local stormwater regulations. In the upper reach, bioengineering solutions were prioritized. This includes removal of invasive species, installation of low rock check dams, and native revegetation. Flow-through pipe systems will allow temporary detention of stormwater, reducing erosive energy while facilitating sediment deposition.
In the downstream perennial reach, hydraulic structures such as J-hooks and cross-vanes are to be strategically placed to redirect flow, stabilize banks, and promote habitat creation. In addition, the project includes urban stormwater wetlands, stream meanders, and pool-and-riffle in-stream habitat, enhancing water quality and sediment retention. Monitoring and adaptive management plans ensure long-term performance and compliance with DuPage County and EPA Section 319(h) guidelines.
Business Impact and Value
The Prentiss Creek Stream Restoration project is projected to provide measurable environmental and community benefits. Sediment reduction is estimated at 248 tons per year, total phosphorus reduction at 182 pounds per year, total nitrogen at 471 pounds per year, and biological oxygen demand at 1,152 pounds per year. These improvements will contribute to meeting Total Maximum Daily Load (TMDL) criteria and local watershed plan goals for the East Branch DuPage River Watershed Plan. A Prentiss Creek Watershed Plan is in progress as of 2026.
Beyond environmental metrics, the project will improve stormwater infiltration, slow peak flow velocities, and stabilize streambanks, protecting property and infrastructure. By integrating ecological design with neighborhood aesthetics, including prairie sod in visible areas and educational signage, the project will deliver both functional and public value, illustrating how Stream Restoration can align municipal priorities with environmental stewardship.
Local and Regional Considerations
Prentiss Creek Stream Restoration will benefit a 2,033-acre area within the Downers Grove watershed, extending to the confluence of the East Branch DuPage River. Local constraints, including residential neighborhoods and a school campus, demanded careful design to minimize flood risk and preserve public spaces. Regional partnerships with the EPA, DuPage County Water Quality Improvement Program, and Illinois Department of Natural Resources ensured alignment with broader water quality and habitat goals.
By enhancing habitat for pollinators, wildlife, and aquatic species, the project will contribute to regional ecological resilience. Furthermore, the educational component provides a long-term community engagement opportunity, fostering awareness of stream management and water quality issues throughout Downers Grove and surrounding areas.
Key Takeaways
The Prentiss Creek Streambank Stabilization Project exemplifies how Stream Restoration can simultaneously address erosion, stormwater management, and habitat improvement. Municipal officials in Downers Grove will achieve measurable environmental, social, and infrastructural benefits through careful planning, ecological design, and regulatory alignment over the course of this project. For municipalities seeking to implement effective waterway restoration projects, engaging expert partners and leveraging integrated solutions is key. Contact A3 Environmental to explore how Stream Restoration can protect your community and restore natural waterways.
