Economics and financing

Cover of Economic Evaluation of Road Investment Proposals: Improved Estimation of Hourly Traffic Volume Distributions
Economic Evaluation of Road Investment Proposals: Improved Estimation of Hourly Traffic Volume Distributions
  • Publication no: AP-R219-03
  • ISBN: 0 85588 647 1
  • Published: 27 July 2003
In Australia, default hourly traffic flow histograms are used in models for estimating savings to road users from road improvement proposals. This report describes the development and updating of hourly traffic volume frequency distributions for use in estimating road user costs as part of the economic evaluation process for road investment proposals. The report concludes that the use of hourly histograms (grouping the 8,760 hours in a year into a number of flow categories) is appropriate, that the accuracy of estimated congestion effects is improved by moving from 4% to 2% class intervals, or by using averages representing each histogram bar rather than mid-point values, and that separate computation for each carriageway on divided roads gives improved results. Existing permanent traffic counting stations were found to be capable of providing the data necessary to develop and update default histograms. Further investigation is suggested of variations in traffic composition with flow. New histograms were developed from recent traffic count data in Victoria, South Australia, Tasmania and Queensland.
  • ECONOMIC EVALUATION OF ROAD INVESTMENT PROPOSALS
  • EXECUTIVE SUMMARY
  • TABLE OF CONTENTS
  • 1. BACKGROUND
  • 2. ACCOUNTING FOR THE EFFECTS OF TRAFFIC VARIATION IN ECONOMIC EVALUATION
  • 3. ESTIMATES OF HOURLY FLOWS BY JURISDICTION
  • 4. SUMMARY AND RECOMMENDATIONS
  • 5. REFERENCES
  • APPENDIX A: MAIN ROADS WESTERN AUSTRALIA – HOURLY FLOW INFORMATION FOR METROPOLITAN URBAN ROAD NETWORK
  • APPENDIX B: IMPROVED HOURLY FLOW MEASUREMENTS FOR PROJECT EVALUATION, MEASURING VARIABILITY IN PROPORTIONS OF COMMERCIAL VEHICLES USING SAMPLE SOUTH AUSTRALIAN DATA
  • INFORMATION RETRIEVAL