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Executive Summary Background The second Strategic Highway Research Program (SHRP 2) has been investigating the critical subject of travel time reliability for several years. As part of this research, SHRP 2 supported multiple efforts to develop products to evaluate travel time reliability and to estimate the impact of projects on reliability. SHRP 2 reliability projects have developed several methods to help public agencies: ⢠Collect and analyze data on the variability of travel time ⢠Diagnose problems ⢠Propose actions or alternative mitigation strategies ⢠Test the impacts of solutions One goal of this research has been to find ways to demonstrate how operational strategies improve travel time reliability, which is highly valued by both the person and goods movement transportation markets. Operational strategies are critical to improve mobility and travel time reliability on highways and can be implemented faster than larger system expansion projects, since they often do not require detailed environmental reviews, and they generally cost much less. In current practice, travel demand and microsimulation models have not been able to adequately estimate the reliability benefits of operations projects. As a result, the SHRP 2 reliability products have the potential to fill a void in the ability of transportation professionals to analyze reliability and quantify the likely benefits of these strategies. Some activity-based models (ABM) with dynamic traffic assignment (DTA) tools under assessment (e.g., in the report, SHRP 2 L04 Incorporating Reliability Performance Measures into Operations and Planning Modeling Tools) may be able to meet this need in the future, but none are currently in widespread use. SHRP 2 L38 Project The SHRP 2 L38 project is intended to provide the necessary testing and feedback on existing SHRP 2 reliability tools. The request for proposal (RFP) for SHRP 2 L38 listed the following objectives: 1. Assist agencies in moving reliability into their business practices through testing of data integration and analytical tools developed by SHRP 2. Include a data collection/integration component, an analytical component, and a decision-making component. 1
