Analysis of Congestion Scenarios in Long Range Plans Using Travel Forecasting Models

Sunday, January 1, 2017
Strategic and Sketch Modeling

This report describes the process of developing, analyzing, and displaying results of a scenario forecasting process using travel demand models. A Travel Time Index (TTI) is the ratio of travel time without congestion (called free flow) and congested travel times, usually during a peak period. With this common measure, planners can compare and contrast the various levels of congestion between urban areas, scenarios within urban areas, and track congestion levels over time. This report is a guide for forecasting TTI using traditional travel demand models to analyze relative impacts of various trip reduction and modification scenarios from long range planning models. The TTI is used in this context as a measure to indicate the reasonableness of asserted changes made to a trip-based travel demand model that reflect the behavioral changes that could be brought about as a result of specific congestion reduction strategies. The webinar is also available.