WBK 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 improvements included re-alignment of the creek with stream riffles, deep pools in channel banks, variable bank slopes and reduced channel conveyance. These geomorphic features provide variety of aquatic plant and animal habitat and reconnect the stream to the floodplain. 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.
Included in the scope of improvements were the design of a multi-use path and two bridge structures. The realignment of the stream impacted an existing equine trail and provided an opportunity for the FPDDC to introduce trail modifications that followed the site master plan. WBK designed two bridges, an access road slab bridge to replace the existing deteriorating structure and a new single span refabricated pedestrian truss bridge over the realigned channel. The new bridge served as a connection between the old and new trail systems within St. James Farm.
The Spring Brook project earned a Special Achievement Award presented by the ACEC Illinois in 2017.