Lake County (Illinois) Division of Transportation Fairfield and Gilmer interchange improvement

Project Summary

Hanson was chosen by the Lake County Division of Transportation to improve the Fairfield and Gilmer intersection in Lake County, Illinois. With 19,000 vehicles traveling this stretch of Fairfield daily, it was already the scene of frequent traffic back-ups and accidents that prevented residents from entering and exiting their driveways during peak commuting hours.  And officials projected residential and commercial developments in neighboring counties would soon increase traffic volume. 

The Lake County DOT’s ultimate goal was to complete a capacity-improvement project that would improve the quality of life for area residents and motorists without disrupting the rustic, rural setting surrounding Fairfield and Gilmer roads.  After investigating several options and conducting preliminary engineering studies, Hanson and the Lake County DOT determined that an at-grade intersection would provide the most benefits to motorists, residents and the surrounding community.

A rigorous construction schedule was established, commencing construction in the fall of 2006, completing major reconstruction work during the summer months of 2007 and reopening in the fall of 2007.  Hanson not only met the challenge, completing the first grade-separated interchange constructed on Lake County’s highway system, but finished the project six weeks ahead of schedule.

This project included the following improvements:

  • construction of a bridge with a single 76-foot span, 54-inch steel-plate girders and closed abutments,
  • construction of new pavement on Fairfield Road, Gilmer Road and a new connector road,
  • construction of a retaining wall on the east side of Fairfield Road,
  • construction of storm sewer and stormwater management facilities, and
  • implementation of aesthetic improvements including landscaping and rustication of concrete faces, decorative bridge rail and fencing.


During the first phase of construction, the contractors and construction team performed the following tasks:

  • constructed temporary pavement on the west side of Fairfield Road,
  • rerouted traffic to temporary pavement, maintaining the intersection as a four-way stop,
  • completed utility relocations, and
  • closed the west end of Hafer Road.


During the second phase of construction, the contractors and construction team installed the caisson foundation system for the retaining wall on the east side of Fairfield Road and constructed a cul-de-sac on Hafer Road. Continuing the accelerated schedule, the contractors, construction team and Lake County kicked off phase three by installing detour route signage and constructing the bridge on Gilmer Road. They also constructed a detention basin, excavated Fairfield Road, raised Gilmer Road, constructed the base for the connector road, completed the retaining wall on the east side of Fairfield Road and completed roadway paving. On Aug. 15, 2007, Lake County opened Fairfield Road, the west leg of Gilmer Road and the connector road to traffic — six weeks ahead of schedule.