Illinois Route 7 over Chicago Sanitary Ship Canal and Des Plaines River (PTB 207, Item 9)

Illinois Department of Transportation

OBJECTIVE

The Illinois Route 7 bridge over the Chicago Sanitary Ship Canal and Des Plaines River is a 25-span, 3,173-foot-long structure with one lane of traffic in each direction and 10-foot-wide shoulders. The existing bridge does not effectively accommodate the heavy truck traffic associated with this principal arterial roadway. Several waterways and railroad corridors intersect or pass beneath the route, adding complexity to the project. Hampton, Lenzini and Renwick, Inc. (HLR) is providing Phase I engineering services to assess potential solutions for the bridge.

PROJECT DESCRIPTION

HLR’s Phase I engineering work includes topographic and hydraulic surveys, environmental data review and inventory, Section 4(f) review, bridge inspection and condition report, hydraulics and drainage studies—including a 2D model of the Des Plaines River and an abbreviated location drainage study—geometric studies, crash and safety analyses, and a NEPA project report. The project is currently programmed for bridge replacement; however, HLR is evaluating repair or rehabilitation options, including partial and complete replacement on a new alignment, as part of the Bridge Condition Report for SN 099-0185.

Coordination with the City of Lockport is essential, as the selected alternative must consider the local agency’s request for a shared-use path over the bridge. The project’s initial environmental processing is an Environmental Assessment, but it is expected to be reclassified as a Federally Approved Categorical Exclusion after the first FHWA meeting, once initial studies and alternative selection are complete.

HLR is also managing four subconsultants responsible for survey work, hydraulic reports, lighting assessments, public involvement, maintenance of traffic, Federal Aviation Administration coordination, and Quality Assurance/Quality Control of all project documents.