Integrating Transit into Traffic Impact Studies

Focus Area

Project Delivery/Streamlining








1-2 years

Research Idea Scope

Local and state agencies are required to study traffic impacts of all new highway projects.  Historically traffic models have done a poor job of integrating transit information into the analysis and must be improved to ensure project decisions are made with the best possible information.  The integration of transit involves looking beyond the automobile and assessing multi-stage trips that include transit and support modes including park and ride lots, bicycle facilities, and pedestrian travel.  Traffic analysis must be able to compare project alternatives across modes (highway expansion versus adding additional train service along a corridor) so decision makers have the information needed to properly select the best project to address a specific transportation need.  The lack of reliable transit elements in our traffic impact analysis skews the traffic analysis results towards automobile dependent solutions and hinders an agency’s ability to promote multimodal improvements. The objective of the research is the identification of models and traffic analysis methodology that fully incorporate transit in the analysis and allow the performance comparison of all potential project alternatives regardless of mode.

Urgency and Payoff

Comprehensive multimodal traffic analysis will improve the ability of an agency to identify the best project alternative regardless of mode.

Suggested By

Scott Sauer, California Department of Transportation (Caltrans)

[email protected]