City of Joliet

Houbolt Road at I-80 DDI Interchange

A Heavily Traveled Corridor

The Houbolt Road Interchange with I-80 is a major connection between the interstate and a busy section of southwest Joliet. The Houbolt Road corridor is home to Joliet Junior College and Joliet Regional Airport along with a casino and trucking / railroad centers to the south, which comprise the nation’s largest inland port. Many businesses within industrial parks, the Forest Preserve District of Will County, and residential neighborhoods are also part of this heavily traveled corridor. 

Improving an Interchange within a Tight Existing Footprint

This busy interchange has recently been connected across the Des Plaines River and accommodates trucking traffic from the Centerpoint development and beyond. The amount of traffic continues to increase significantly, and improving the interchange to a Diverging Diamond (DDI) configuration within the existing footprint underneath the I-80 structures provides improved access to I-80 for the future.

Unique and Efficient

The DDI design provided more efficient and cost effective construction by fitting the interchange within the footprint of the existing bridges. A limited number of DDIs have been implemented in Illinois over the past decade. However, this project is unique as the first DDI in Illinois where the cross street (Houbolt Road) goes under the expressway (I-80).

Civiltech Provided Construction Engineering Services

The DDI conversion project and reconstruction with widening of existing Houbolt Road was built in tandem to a project that extended Houbolt Road south of US Route 6 and included the construction of a new major river bridge over the Des Plaines River. Civiltech served as Construction Engineer on the complex DDI conversion and Houbolt Road Reconstruction / Widening.

Working Around Existing Expressway Structures

The Houlbolt Road Improvement encompasses a wide array of structural and roadway items. Micro-pile supported retaining walls provided the required space under the I-80 bridges for the diverging diamond at grade lanes. Overhead clearance restrictions caused by the I-80 bridges were accommodated with the use of micro-piles which can be installed without the need for tall cranes.

Accommodating the Road Widening

Two structures over Rock Run Creek and the I&M Canal along with a pedestrian underpass carry the new lanes over those existing crossings. Two MSE retaining walls solved the right of way restrictions surrounding the widened cross sectional footprint near the I&M Canal.

Traffic Signals and Street Lighting

Five interconnected traffic signals were installed. Also, roadway, interchange, and underpass lighting was upgraded.

Additional Considerations

The at-grade crossing of the CSX Railroad had to be reconstructed to accommodate the wider cross section. Tight width restrictions for the DDI were overcome by placing an existing pedestrian path in the median under the I-80 bridges. A drainage storage basin was created as part of the improvements and the excavated material was then used for raising Houbolt as it approaches US 6.

This Project Incorporates the Following:

  • Accommodating increasing traffic loads
  • Diverging Diamond Interchange (DDI)
  • DDI configuration unique to Illinois
  • Construction within the existing footprint
  • Micro-pile retaining walls
  • Pedestrian underpass
  • MSE retaining walls
  • Interconnected traffic signals
  • Roadway lighting
  • At-grade railroad crossing

Scope of Services

  • Resident Engineering
  • Construction Inspection
  • Construction Management
  • Construction Layout
  • Construction Documentation
  • Stakeholder Coordination
  • Public Involvement
  • QC/QA Material Testing


  • State, Local

Learn more about this project and its related services.

Contact Jim Ewers