Overview

The Illinois Department of Transportation is currently conducting a preliminary engineering and environmental study (Phase I) for the improvement of Illinois 173 in Boone County. The study limits include Illinois 173 beginning 0.4 miles west of the Village of Poplar Grove and extending east to Boone-McHenry County Line Road, over 8 miles.

Illinois 173 is a primary east-west corridor through Boone County and the Villages of Poplar Grove and Capron. The purpose of the study is to preserve, rehabilitate, and reconstruct aging pavement, constructed in 1928, and provide safe and efficient transportation for all users.

The scope of the proposed improvements include:

For this study, the rural highway sections are as follows: 

• From 3,351 feet west of Westergren Way, in the Village of Poplar Grove, to approximately 707 feet west of Westergren Way (length of approximately 0.501 miles).
• From 150 feet east of Carson Drive, in the Village of Poplar Grove, to approximately 673 feet west of Wooster Street, in the Village of Capron (length of approximately 4.491 miles).
• From approximately 202 feet east of East Street, in the Village of Capron, to the Boone-McHenry County Line Road (length of approximately 1.469 miles).
• Rehabilitation of pavement for the travel lanes consisting of:
  • A hot mix asphalt layer on a cold in-place recycled base.
• Roadway typical cross section in each direction of travel is to consist of:
  • A 12-foot-wide travel lane.
  • An 8-foot-wide shoulder are to be provided for safety and bicycle accommodations. The shoulder improvements consisting of:
    • A 5-foot-wide paved shoulder including rubble strips,
    • A 2-foot-wide aggregate shoulder, and
    • A 1-foot-wide turf shoulder.
  • Roadside safety and roadside ditch improvements.
  • 14 cross culvert improvements for safety and capacity by rehabilitation or replacement.
  • Existing guardrail
    • At locations where roadside safety improvement can be achieved the existing guardrail is to be removed.
    • At locations where roadside safety improvement cannot be achieved the existing guardrail is to be rehabilitated to current standards.
    • No new locations of guardrail are proposed
  • Intersecting crossroads approached are to be improved to current standards
  • Driveways are to be improved to accommodate roadway improvements, to improve safety, and to replace driveway culverts.

For this study, the Village of Poplar Grove section is as follows:

• From approximately 707 feet west of Westergren Way and continues east through the Village of Poplar Grove to approximately 150 feet east of Carson Drive (length of approximately 0.946 miles).

Preservation pavement consists of: 

• Milling of existing pavement and new surface.
• ADA curb ramp improvements to achieve current ADA compliance
• High visibility crosswalks at State Street’s school route crossings

For this study, the Village of Capron section is as follows:

• From approximately 673 feet west of Wooster Street and continues east through the Village of Capron to approximately 202 feet east of East Street (length of approximately 0.663 miles).

Reconstruction of pavement 

• Roadway typical cross section in each direction of travel is to consist of:
  • A 12-foot-wide travel lane,
    • A 5-foot-wide urban shoulder,
    • An 8-foot-wide parking lane where parking exists
    • A combination curb and gutter.
  • Roadside safety improvements
  • On road bicycle accommodations
  • Pedestrian and ADA Improvements
    • Curb Bump Outs on Illinois 173 at locations with parking
      • Reduce pedestrian crossing distance
      • Increase pedestrian visibility to motorist
    • Improved ADA accessibility routes
    • Improved curb ramps
    • High visibility crosswalks at Wooster Street’s school route crossings and at the Long Prairie Trail Crossing
  • Stormwater Drainage Improvements

Partial history of Illinois 173 from 0.4 miles west of the Village of Poplar Grove to Boone-McHenry County Line Road:

• 1928: The current Illinois 173 pavement in the study limits was constructed.
• 1974:  The pavement was rehabilitated and widened from east of Poplar Grove to east of Capron and the culvert at 0.3 miles east of Meier Road was replaced.
• 1993: The culvert at 1.2 miles east of Meier Road was replaced.
• 1998: The culvert near Ellingson Road was replaced.
• 2000: The bridge over Piscasaw Creek was replaced.
• 2001: The pavement was rehabilitated.
• 2004: The pavement was rehabilitated and widened through Poplar Grove.
• 2007: The bridge over Beaver Creek was replaced.

Existing Annual Average Daily Traffic (AADT) as measured in vehicles per day (VPD) on Illinois 173 in the study limits ranges from 4,850 at the west end to 5,000 at the east end.