Spring Brook Creek and Wetland Restoration

The Bodwé Infrastructure team led by WBK Engineering worked with the Forest Preserve District of DuPage County and The Wetland Initiative (TWI) to restore and naturalize Spring Brook No. 1 Creek and wetlands through the St. James Farm and Blackwell Forest Preserves. The FPDDC is partnering with the Illinois State Toll Highway Authority (ISTHA) on the restoration as part of the required “Waters of the US” mitigation for the Authority’s Elgin-O’Hare Western Bypass Project.

The waters mitigation and restoration project was divided into three geographic phases. The project team developed a construction plan set for Phase 1, which consists of an area of Spring Brook No. 1 Creek within St. James Farm Forest Preserve. The project was evaluated with respect to the United States Army Corps of Engineers (USACE) rules for the mitigation policy and designed in accordance with US EPA and USFWS guidelines. The team then worked with the Tollway and FPDDC in the development of performance standards and measurement methods appropriate for this mitigation project.

Channelized decades ago to support mass agriculture, our team of environmental scientists and water resources engineers re-meandered the stream.

The design seeks to optimize water quality benefits and enhance natural habitat by mimicking natural processes. The processes include geomorphologic features such as stream re-meandering, stream riffles, deep pools in channel bends, variable bank slopes, and reduced channel conveyance. These features provide variability of aquatic plant and animal habitat, reconnect the stream to the floodplain, and increase opportunities for removal of excess water-borne nutrients. Wetland creation was facilitated by stream improvements as well as field tile removal and modification. The stream re-meander was hydraulically modeled using HEC-RAS to check the effectiveness of the geomorphological enhancements by assessing bank-full flow conditions, flood inundation areas, and flow velocities and also was modeled in FEQ software to demonstrate compliance with IDNR-OWR requirements. As part of the design process, HEC-RAS was integrated with CAD design software via HEC-GeoRAS to ensure a high degree of precision in the model and to provide an efficient design workflow.

The project team has provided and will continue to provide the following:

• Stream assessment and mitigation plan design

• Final plans, specifications and estimates

• Wetland review

• On-site surveys

• Permit agency coordination

• Post-construction monitoring, wetland assessments, and reporting