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Illinois Route 31 Study

The Illinois Department of Transportation (Department) has completed a preliminary engineering and environmental study (Phase I) for the improvement of IL 31 from IL 176 to IL 120 in McHenry County.  The general scope of work for this improvement is anticipated to consist of roadway widening and reconstruction to provide two lanes in each direction separated by a median, bicycle and pedestrian accommodations, and intersection and drainage improvements. This improvement is included in the Department’s FY 2020-2025 Proposed Highway Improvement Program.  Current engineering efforts are targeted to enable a contract letting in the later years of the multi-year program contingent upon plan readiness, land acquisition, and funding availability through future annual legislative appropriations.

Phase II contract plan preparation is expected to begin later this year.

Note: IDOT projects typically have three distinct phases. Phase I (or the project Study) consists of developing the project scope, environmental studies and preliminary design of a project. Phase II (Design) consists of refining the design to develop contract plans and land acquisition. Phase III (Construction) consists of the actual construction of the project.



This section will be updated as the project progresses.


This section will be updated as the project progresses.