Travel demand modeling is an important tool in the transportation planning community. It helps forecast travel
characteristics into the future at various planning levels such as state, region and corridor. Using travel demand
modeling to evaluate different situations (changes in land use and/or transportation network) would allow
Metropolitan Planning Organizations’ (MPOs) staff make educated decisions regarding growth and
improvements to their respective regional transportation networks. Several small (50,000< population
<200,000) and medium (200,000 <population <500,000) sized MPOs in the state of Illinois utilize TDM for
different transportation planning purposes, most commonly, the Long Range Transportation Plan (LRTP) and
Transportation Improvement Program (TIP). Some of the small and medium sized MPOs in the state of Illinois
are unable to utilize TDM tools primarily due to lack of available resources and guidelines at the regional and
state level. This study sought to establish the framework necessary for the development, maintenance, and
application of small and medium sized MPOs’ TDMs. It is crucial for the local, regional, and state agencies to
play a collaborative role in the transportation planning process. This study established a framework for
developing travel demand models at the MPO regional level considering their limited available resources.
Special attention was given to simplicity and accuracy of the travel model development process. Extensive
calibration and validation checks were recommended, as accuracy of travel forecasting is of high importance.
As an important part of this study, a statewide group, the Illinois Modeling Users Group (IL-MUG) was created
to support, set standards and guide the development, implementation, and maintenance of travel demand
models in small and medium sized MPOs in Illinois.Illinois Department of Transportation ICT R27-48published or submitted for publicationnot peer reviewe