Travel Demand Modeling

This page contains information about TCRPC’s travel demand modeling (TDM) activities.

What is TDM?

Traffic on the roads results from individuals deciding where, when, and how to travel. Decisions such as where to live, work, and shop also impact travel behavior. Transportation planners use the travel demand model to understand travel behavior and predict future travel demands. The travel demand model is a computationally complex tool that uses a set of mathematical procedures and equations that represent the variety of transportation choices people make, and how those choices result in trips on the transportation network. The TDM uses demographic data, such as population and employment data, to guide the model to mathematically predict travel patterns within an area.

How does TCRPC use TDM?

The Tri-County Regional Planning Commission uses the TDM as part of the Long-Range Transportation Planning process to guide potential changes to the regional transportation network. Additionally, TCRPC uses the TDM in the STBG programming process to inform the regional value of individual projects. Lastly, TCRPC allows partner agencies to utilize the TDM when overseeing road projects which may significantly alter traffic patterns when construction causes extended periods of road closures or detours.

TCRPC's TDM Background

Tri-County Regional Planning Commission maintains a regional travel demand model (TDM) for Peoria, Tazewell, and Woodford counties. In 2023, Tri-County transitioned its TDM to an Activity-Based Travel Demand Model (ABM) with a base year of 2021 and a future year of 2050. The transition of the ABM allows for Tri-County to move from Trip based predictions to activity-based predictions by forecasting the demand for people’s requirement to participate in various activities.

The ABM is comprised of a series of models that predict various household- and person-level decisions made by the residents of the tri-county region. These decisions are based on, but not limited to:

  • Driver license ownership
  • Auto ownership
  • Work-based activities
    • Employed full-time or part-time
    • Work attendance and duration
    • Remote work percentage (by work industry)
  • Household members attend
    • Daycare
    • School
    • College

Staff Contact

Have an idea that can use the TDM to benefit your project or community?

Contact Staff for more information!
Michael Bruner
Senior Planner

Skip to content