Tri-State Tollway -Plainfield Road and Flagg Creek

  • Tri-State Tollway -Plainfield Road and Flagg Creek


Client: Illinois Tollway

Location: Plainfield Road & Flagg Creek, IL


The project consisted of Phase II engineering services for work tasks that included preparation of contract plans and engineering studies as well as other technical services.

The scope of this project was to replace and upgrade and outdated, frequently congested roadway with a corridor that will better serve the region’s transportation network while improving safety and efficiency.

The work for this project included:

  • Replacement and lengthening of the existing Plainfield Road Bridge
  • Construction of new bridge with pedestrian paths
  • New bridge piers to accommodate future widening of I-294
  • Construction of retaining walls for bridge
  • New Plainfield road configuration with expanded lanes
  • Approximately 500 feet of roadway improvements
  • Site clearing and grading
  • Relocation of Flagg Creek
  • Drainage improvements

Services Provided

d’Escoto provided the following Phase II civil design engineering services for Plainfield Road and Flagg Creek:

  • 3D modeling of Plainfield Road and Flagg Creek
  • 3D modeling of retaining walls and bridge footings to aid in structural design
  • Completion of plans for roadway design, removal, grading, and cross-sections
  • Preparation of schedules for pay item quantities and earthwork
  • Preparation of a project cost estimate using historical data

d’Escoto used 3D modeling techniques to provide a fast and error-free method for creating grading plans, cross-sections, and earthwork schedules. This also allowed for a seamless transition to the drainage team, allowing them to quickly model the proposed Flagg Creek.  d’Escoto also compiled pay item quantities from all disciplines and used advanced search tools to ensure pay item consistency between the plans, specifications, and schedule of quantities.