Estimation and valuation of travel time reliability for transportation planning applications

This paper proposes a method to measure the value, forecast, and incorporate reliability in the transportation planning process. Empirically observed travel time data from INRIX are used in an introduced method to measure Origin Destination (OD)-based reliability. OD-based reliability is a valuable concept, since it can be easily incorporated in most travel models. The measured reliability is utilized to find the value of reliability for a specific mode choice problem and to establish the relationship between travel time and reliability. This relationship is useful to forecast reliability in future scenarios. Findings are combined with Maryland Statewide Transportation Model to find the value of reliability savings by improving the network in a case study. The Inter-County Connector is used as the case study to show the significance of reliability savings. The proposed approach can be used to (1) provide a systematic approach to estimate travel time reliability for planning agencies, (2) incorporate travel time reliability in transportation planning models, and (3) evaluate reliability improvements gained from transportation network investments.