More reliable travel times can improve highway system performance, enhance supply-chain vitality, and reduce frustrating delays in trips we take daily. SHRP 2 project L07: Identification and Evaluation of the Cost-Effectiveness of Highway Design Features to Reduce Non-recurrent Congestion addresses how transportation agencies can improve travel time reliability through geometric design treatments that reduce delays caused by unexpected congestion. Three separate analyses of the design treatments were conducted: operational, safety, and benefit-cost. The results of this research provide a method for incorporating the economic savings from both reduced delay and improved reliability for a design treatment over its life cycle. Design treatments that are commonly used to address recurrent congestion can also be analysed using the approach developed in this research, which takes into account not only the delay improvements associated with the treatment, but the potential improvements to reliability as well. Taking these benefits into account results in a more accurate valuation of a design treatment's net present benefit and benefit-cost ratio. This final report describes the results. The project developed a Design Guide for Addressing Non-recurrent Congestion,* which is a catalogue of the design treatments considered in this research. The Guide (http://onlinepubs.trb.org/onlinepubs/shrp2/SHRP2prepubL07designguide.pdf) provides planners, designers, operations engineers, and decision makers with a toolbox of possible options for addressing non-recurrent congestion through design treatments. The project also developed an analysis tool that can be used to measure the operational effectiveness and economic benefit of design treatments for a freeway segment of interest. The analysis tool (http://www.trb.org/StrategicHighwayResearchProgram2SHRP2/Pages/L07_Anal…) allows highway agencies to compare the benefits and costs of implementing various non-recurrent congestion treatments at specific locations. (Author/publisher)
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