Travel Demand Modeling for the Small and Medium Sized MPOs in Illinois

Travel demand modeling (TDM) 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 TDM to evaluate different situations (changes in land use and/or transportation network) would allow the staff of Metropolitan Planning Organizations (MPOs) to 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 TDMs 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 TDMs in small and medium sized MPOs in Illinois.