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2007-32 Benefit-Cost Analysis for Intersection Decision Support

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2007-32 Benefit-Cost Analysis for Intersection Decision Support 2007-32 Benefit-Cost Analysis for Intersection Decision Support Report #5 in the Series: Developing Intersection Decision Support Solutions e ativ Solutions! nov ..In earch...Knowledge. es Take the steps... R Transportation Research Technical Report Documentation Page 1. Report No. 2. 3. Recipients Accession No. MN/RC-2007-32 4. Title and Subtitle 5. Report Date Benefit-Cost Analysis for Intersection Decision Support October 2007 6. 7. Author(s) 8. Performing Organization Report No. Michael Corbett, David Levinson, Xi Zou 9. Performing Organization Name and Address 10. Project/Task/Work Unit No. University of Minnesota Department of Civil Engineering 11. Contract (C) or Grant (G) No. 500 Pillsbury Drive S.E. (c) 81655 (wo) 33 Minneapolis, MN 55455 12. Sponsoring Organization Name and Address 13. Type of Report and Period Covered Minnesota Department of Transportation Final Report 395 John Ireland Boulevard Mail Stop 330 14. Sponsoring Agency Code St. Paul, Minnesota 55155 15. Supplementary Notes http://www.lrrb.org/PDF/200732.pdf Report #5 in the Series: Developing Intersection Decision Support Solutions 16. Abstract (Limit: 200 words) The Intersection Decision Support (IDS) system is designed to assist drivers on stop-controlled low-volume rural roads choosing gaps when confronted with busy multiple lane divided-highways, without affecting traffic on the high-volume road. The hope is, that by providing better gap guidance, fewer crashes (and fatalities) will occur. This research develops a framework for analyzing such a new, and presently under-specified technology, and illustrates that framework by comparing that with more conventional engineering approaches, as well as a “do- nothing” base case. The results show that the IDS System may be an effective tool to reduce crash rates at various intersections. More research is needed to address reliability and stability issues, and in determining how cost- effective of a solution the IDS System is compared to other “traditional” alternatives. 17. Document Analysis/Descriptors 18. Availability Statement Transportation needs, No restrictions. Document available from: elderly, seniors, disadvantaged National Technical Information Services, populations Springfield, Virginia 22161 19. Security Class (this report) 20. Security Class (this page) 21. No. of Pages 22. Price Unclassified Unclassified 75 Benefit-Cost Analysis for Intersection Decision Support Report #5 in the Series: Developing Intersection Decision Support Solutions Final Report Prepared by: Michael Corbett David Levinson Xi Zou Department of Civil Engineering University of Minnesota October 2007 Published by: Minnesota Department of Transportation Research Services Section 395 John Ireland Boulevard, MS 330 St. Paul, Minnesota 55155-1899 This report represents the results of research conducted by the authors and does not necessarily represent the views or policies of the Minnesota Department of Transportation and/or the Center for Transportation Studies. This report does not contain a standard or specified technique. Table of Contents 1. Introduction........................................................................................................ 1 2. A Brief History and Theory of Benefit-cost Analysis ....................................... 2 3. Benefit-Cost Analysis Framework................................................................... 10 4. Identification of Alternative Countermeasures................................................ 14 5. Lifespan of Countermeasure Components....................................................... 26 6. Infrastructure and Operating Costs of Countermeasures................................. 28 7. Delay Costs of Countermeasures..................................................................... 37 8. Crash-reduction Benefits of Countermeasures ................................................ 40 9. Sensitivity Analysis and Benefit-Cost Analysis Results ................................. 47 10. Recommendations and Conclusions .............................................................. 55 List of Tables Table 3.1: Benefits to Service Providers, Users & Society/Community from IDS ........................................................................................................................ 12 Table 3.2: Cost to Service Provider, Roadway Users and Community/Society.. 13 Table 5.1: Lifespan of Sensor System Components ............................................ 26 Table 5.2: Lifespan of Display System Components........................................... 27 Table 6.1: Costs of IDS System........................................................................... 29 Table 6.2: IDS Computer System Costs .............................................................. 30 Table 6.3: IDS Sensor System Costs ................................................................... 31 Table 6.4: IDS Display System Costs.................................................................. 31 Table 6.5: IDS Traffic Sign Costs........................................................................ 32 Table 6.6: Costs of Alternative Countermeasures ............................................... 33 Table 6.7: Directional Median Opening Component Costs................................. 34 Table 6.8: Directional Median Opening Pavement Markings Cost..................... 34 Table 8.1: Costs of Crashes ................................................................................. 40 Table 8.2: Damage Severity Classification in Police Traffic Accident Reports.. 41 Table 8.3: Annual Crash Rates and Costs for US 52 and CSAH 9 ..................... 41 Table 8.4: Probability of TTCs less than zero ..................................................... 43 Table 8.5: Crash Reduction Benefits from Directional Median Opening, as determined by the Collision Diagram (Appendix A)............................................ 45 Table 8.6: Crash Reduction Benefits from Directional Median Opening as determined by several recent studies .................................................................... 46 Table 9.1: Benefit-Cost Ratios for the IDS and DMO Alternatives.................... 53 List of Figures Figure 2.1: Probability-density distribution of net present values approximated by a normal curve.................................................................................................... 6 Figure 2.2: Cumulative-probability distribution of net present values approximated by a curve......................................................................................... 7 Figure 2.3: Probability distribution curves for the NPVs of projects A and B...... 8 Figure 2.4: Probability distribution curves for the NPVs of projects A and B, where Project A has a narrower range of possible NPVs ....................................... 9 Figure 3.1: Benefit-cost Analysis for IDS Project............................................... 11 Figure 4.1: Median left-turn acceleration lane..................................................... 18 Figure 4.2: Obstructed Sight distance due to opposing left-turning vehicles...... 19 Figure 4.3: Effects of off-set left-turn design on sight distance .......................... 20 Figure 4.4: Intersection with offset right and left turn lanes................................ 20 Figure 4.5: Offset T-Intersection ......................................................................... 21 Figure 4.6: Indirect left-turn Median U-Turn ...................................................... 22 Figure 4.7: Indirect left-turn jug handle............................................................... 23 Figure 4.8: Indirect left-turn loop ........................................................................ 24 Figure 4.9: Directional Median Opening............................................................. 25 Figure 6.1: Directional Median Opening Crash Reduction and Increase Locations............................................................................................................... 36 Figure 8.1: Probability Distribution of TTCs ..................................................... 42 Figure 8.2: Probability Distribution of Accident Reduction Percentages............ 44 Figure 9.1: Probability Distribution of Costs for IDS System............................. 48 Figure 9.2: Probability Distribution of Benefits for IDS System ........................ 49 Figure 9.3: Probability Distribution of Benefit-Cost Ratio for IDS System........ 49 Figure 9.4: Probability Distribution of Costs for Directional Median Opening.. 50 Figure 9.5: Probability Distribution of Benefits for Directional Median Opening................................................................................................................. 50 Figure 9.6: Probability Distribution of Benefit-Cost Ratio for Directional Median Opening.................................................................................................... 51 Figure 9.7: Comparison of Probability Distribution of Costs for IDS and DMO Alternatives................................................................................................. 52 Figure 9.8: Comparison of Probability Distribution of Benefits for IDS and DMO Alternatives................................................................................................. 52 Figure 9.9: Comparison of Probability Distribution of Benefit-Cost Ratios for IDS and DMO Alternatives............................................................................. 53 Executive Summary
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