ACCIDENT RATES AND COSTS ON URBAN ARTERIALS AND FREEWAYS

A MATHEMATICAL MODEL IS DEVELOPED TO DESCRIBE ACTUAL COSTS OF ACCIDENTS IN URBAN REGIONS FOR BOTH FREEWAYS AND ARTERIALS. ACCIDENT COST BENEFITS ACCRUING TO HIGHWAY USERS (OR THEIR INSURANCE COMPANIES) THROUGH CONSTRUCTION OF INTERSTATE ROUTE 5 IN SEATTLE ARE ANALYZED, WITH BENEFITS COMPUTED FOR 1968. PREVIOUS STUDIES BY OTHER STATES, PARTICULARLY MASSACHUSETTS AND THE DISTRICT OF COLUMBIA, ARE EXAMINED WITH RESPECT TO THEIR METHODOLOGIES AND CONCLUSIONS. IT IS SHOWN THAT PERSONAL LOSS, ESPECIALLY IN FATAL ACCIDENTS, IS OVERRATED AS A PROPORTION OF TOTAL ACCIDENT COST, OF WHICH ABOUT 60% SHOULD PROPERLY BE ALLOTED TO PROPERTY DAMAGE. USE OF THE MODEL ON EMPIRICAL DATA FOR THE YEARS 1958--1968 RESULTS IN FREEWAY AND ARTERIAL ACCIDENT COSTS OF $895 AND $715, RESPECTIVELY; BUT THESE ARE CONSIDERED CONVERSION FACTORS, RATHER THAN TRUE COSTS, TO USE IN ACCOUNTING FOR BOTH REPORTED AND UNREPORTED ACCIDENTS. THE REDUCTION IN ACCIDENT RATES ON THREE ARTERIALS AFFECTED BY THE OPENING OF THE FREEWAY IN 1962 IS FOUND NOT TO BE STATISTICALLY SIGNIFICANT. HOWEVER, TRAFFIC DIVERTED TO THE FREEWAY FROM ARTERIALS HAS REALIZED A BENEFIT OF $2.79 MILLION (1968, PROPERTY DAMAGE ONLY); BUT IF PDO REPRESENTS 60% OF ACCIDENT COST, THE TOTAL BENEFIT REALIZED IS ABOUT $4.57 MILLION. THIS BENEFIT IS APPROXIMATELY 1200% OF THE FUEL SAVING BUT ONLY 15% OF THE TIME SAVING REALIZED BY THE FREEWAY.

  • Supplemental Notes:
    • Res Rept No 14B, 31 PP, 5 FIG, 2 TAB, 1 APP
  • Corporate Authors:

    University of Washington, Seattle

    Seattle, WA  USA  98195
  • Authors:
    • MATTESON, J H
    • Hall, J W
    • SAWHILL, R B
  • Publication Date: 1970-1

Subject/Index Terms

Filing Info

  • Accession Number: 00221142
  • Record Type: Publication
  • Files: TRIS
  • Created Date: Dec 7 1970 12:00AM