Calculating and Forecasting Induced Vehicle-Miles of Travel Resulting from Highway Projects: Findings and Recommendations from an Expert Panel

In the context of implementation of SB 743 (Steinberg, 2013), staff at the California Department of Transportation (Caltrans) have been developing guidance documents on how to calculate induced travel, working with their counterparts at the California Air Resources Board (CARB) and the Governor’s Office of Planning and Research (OPR). OPR’s technical advisory discusses two methods for estimating induced travel: an approach based on the application of travel models and an approach using elasticities drawn from the peer-reviewed literature (such as the National Center for Sustainable Transportation (NCST) induced travel calculator. Caltrans is developing internal guidance to help its analysts choose the best method (or combination of methods) for assessing induced travel from projects on the State Highway System, and has been holding meetings to provide stakeholders with opportunities to express their views and voice their concerns about the drafts.