Illinois Department of Transportation, Erica Borggren, Acting Secretary
Patrick J. Quinn, Governor
Traveling PublicMapsProjectsRoad ClosuresNewsDoing BusinessLetting & BiddingCareers@IDOTGeneral Info

Project Overview

US 20 (FAP 301) is one of the oldest transcontinental highways.  It stretches across eleven states, crossing four time zones, from Boston, Massachusetts, to Newport, Oregon.  Covering 3,365 miles, it is the longest continuous highway in the United States.  In Illinois, US 20 runs from Chicago at the Indiana state line to East Dubuque at the Iowa state line, serving the northern part of the state. In 1955, it was officially designated the Ulysses S. Grant Memorial Highway by the Illinois General Assembly.  US 20 serves the City of Rockford as a business route through the center of the City and also as a bypass route through the south part of the City. 

Existing Conditions
The US 20 Bypass is a four-lane access controlled rural freeway with a grass median.  There are three interchanges located within the project limits:  US 20 and IL 251, US 20 and Alpine Road, and US 20 and I-39.  There are 14 structures in the project limits.

Existing and projected traffic for the various segments within the project limits are as follows:

Average Daily Traffic (ADT)





IL 2 to IL 251




IL 251 to Alpine Rd.




Alpine Rd. to I-39




Click here to see the traffic exhibit.

There are numerous crashes with varying severity of personal injury, especially at the cross street and ramp intersections at the IL 251 and Alpine Road interchanges. Click here to see the crash diagram

Need for Improvement 
Based on current IDOT design standards and an analysis of the projected traffic on the four-lane freeway, it was determined that the existing facility would operate inefficiently in the design year of 2035.  The mainline requires six lanes, three lanes in each direction, to efficiently operate considering the anticipated future traffic growth by the year 2035.

Improved traffic safety will also be addressed. The existing geometry on the entrance and exit ramps does not meet current geometric standards.  Geometric improvements at the interchanges and adjacent cross road intersections will be designed to reduce future crash potentials.

Proposed Scope of Work

The Illinois Department of Transportation has initiated a Phase I Preliminary Engineering Study to evaluate alternatives for adding lanes on the US 20 Bypass from IL 2 to Interstate 39 (I-39), as shown on the Project Location Map (click here). The study includes an evaluation of reconstruction alternatives designed to improve safety and traffic flow at three interchanges including US 20 at IL 251, US 20 at Alpine Road, and US 20 at I-39.  The US 20 interchange at IL 2 is not included, but is being studied as a separate project.  Local intersections adjacent to the interchanges on IL 251 (11th Street) and Alpine Road will also be studied.  Bridges within the project limits will be replaced or otherwise reconstructed.

As part of the project work, the following will be included in the study:
  • crash analysis
  • traffic projections and operational analysis
  • hydraulic and drainage analysis, including the four bridges over the Rock River
  • development of interchange concepts
  • alternates to add mainline freeway lanes
  • bridge analysis to determine type of reconstruction
  • environmental inventory and analysis
  • operational analysis of intersections on either side of the IL 251 and Alpine Road interchanges

Two public informational open house meetings are included in this preliminary engineering study. These meetings will give the general public and local agencies additional opportunity to provide input into the proposed improvement alternates.

A Combined Design Report will be prepared presenting the findings and analyses and will recommend a preferred alternative for the proposed improvement.  This Report will provide the basis for development of the contract plans during the next phase of engineering.

US 20
(Rockford Bypass)
from IL 2 to I-39

Project Overview
Project Location Map
Project Development Process
Project Timeline
Project Exhibits
Public Involvement
Contact Us
IDOT Privacy Statement | Illinois Privacy Information | Kids Privacy | Web Accessibility  | FOIA