Chicago Department of Transportation

Hydraulic Analysis & Permitting on the Chicago Riverwalk

Chicago, IL

The long anticipated Chicago Riverwalk, which connects the City’s lakefront to the West Loop, is a true testament to engineering innovation and collaboration. The Chicago Department of Transportation (CDOT) planned the project to enhance the cultural, environmental, economical and recreational aspects that the Chicago River has to offer. Benesch served as lead structural designer and construction manager on the overall project and led extensive hydraulic analysis.The scope of work included planning and design services for the Riverwalk, assessment of the navigational traffic on the main branch of the Chicago River and evaluation of potential impacts caused by the build-out on the waterway system.

CDOT obtained approval for 20-foot build-outs into the river at each bridge and 25-foot build-outs between bridges. Fifty feet was allowed on the block between Franklin and Lake Streets where the river widens at a curve. Assessment of the ecological and hydrological impacts of the Riverwalk build-out was also required, along with a navigational traffic assessment for the potential docking of recreational boats, commercial tour boats and water taxi services.

Another major component of this project included preparation of all documents necessary to obtain Section 401 Water Quality Certification from the Illinois EPA, including an approved Anti-Degradation Assessment for the Chicago River. The project also required Section 404 permit acquisition from the U.S. Army Corps of Engineers (USACE), including mitigation for fill of two acres of Waters of the U.S. In addition, Benesch collaborated with the USACE in the preparation of the Hydraulic Report for approval by the Metropolitan Water Reclamation District of Greater Chicago. The Hydraulic Report detailed hydraulic impacts on the river, including when flows are reversed in flood events.

Project highlights

  • Hydraulic modeling of the Chicago River using HEC-RAS
  • Extensive coordination and permitting with city, state and federal agencies
  • Compatibility between existing and new dock wall structural systems
  • Extensive coordination with project disciplines, including architectural, drainage, electrical and landscaping
  • Limited overhead construction clearances below the bascule bridges