Can transportation planning tools forecast Induced Travel?
Travel demand forecasting tools account for some, but not all of the travel behavior that may contribute to increased traffic resulting from a new or widened highway. Current 4-step travel modeling procedures typically include mode choice and trip assignment models, which can be used to forecast those travelers who change from other travel modes or alternate routes, respectively. Trip distribution models that use highway impedances (e.g., travel time) that accurately reflect congested, peak-period conditions can also account for travelers who change their destinations in response to decreased travel times. Current models are generally insensitive to the impacts of highway improvements on travelers who change their time of travel, or those who make entirely new trips. However, travelers who simply change their time of travel do not contribute to a net increase in regional daily VMT, and there is general agreement among transportation planning professionals that entirely new trips repres
