OPTIMIZING STREET OPERATIONS THROUGH TRAFFIC REGULATIONS AND CONTROL

THIS REPORT PRESENTS THE FINDINGS OF A TWO-YEAR PROJECT THAT DETERMINED THE RELATIVE AREAWIDE EFFECTIVENESS OF TRAFFIC ENGINEERING TECHNIQUES IN THE CENTRAL BUSINESS DISTRICTS (CBD) OF TWO SMALL CALIFORNIA CITIES, REDWOOD CITY (POP. 61,000) AND SUNNYVALE (POP. 90,000). THE CITIES PARTICIPATED IN A PROGRAM OF TRAFFIC OPERATIONS RESEARCH, AND THE RESULTS WERE OBTAINED IN A REAL-TIME AND POLITICAL ENVIRONMENT. IN ADDITION, MANY ELEMENTS OF THE URBAN ENVIRONMENT WERE OBSERVED, INCLUDING BUSINESS PERFORMANCE, PUBLIC OPINION, AND POLITICAL PROCESSES. A BASE CONDITION TRAFFIC OPERATIONS PROFILE WAS ESTABLISHED FOR EACH CITY AND WAS USED FOR SUBSEQUENT COMPARISONS AS CHANGES IN TRAFFIC REGULATIONS AND CONTROL WERE IMPLEMENTED AND EVALUATED THROUGH A SERIES OF TEST STAGES. OPERATIONAL TECHNIQUES RANGING FROM RELATIVELY SIMPLE, BUT EFFECTIVE, SIGNAL TIMING TO EXTENSIVE LEFT-TURN PROHIBITIONS AND ONE- WAY OPERATIONS WERE EVALUATED. ANGLE PARKING, NO-STOPPING TOWAWAY, AND UNBALANCED TRAFFIC FLOW WERE ALSO EVALUATED THROUGHOUT AN AREA OF URBAN STREETS. AVERAGE SPEEDS, STOPS, DELAYS, AND A VARIETY OF OTHER MEASURES WERE USED TO DETERMINE THE RELATIVE MAGNITUDE OF OPERATIONAL EFFICIENCY ON AN AREA-WIDE BASIS. BUSINESS PERFORMANCE, PUBLIC ACCEPTANCE, AND DRIVER OBSERVANCE WERE ALSO MEASURED FOR EACH COMBINATION OF TRAFFIC IMPROVEMENT TECHNIQUES. THE GREATEST IMPROVEMENT IN OPERATIONAL EFFICIENCY WAS FOUND IN REDWOOD CITY WITH A COMBINATION OF ONE-WAY AND UNBALANCED FLOW COUPLETS. FROM A PUBLIC OPINION AND BUSINESS PERFORMANCE STANDPOINT, THIS TEST STAGE WAS THE LEAST OBJECTIONABLE AND IS CONSIDERED THE ONE MOST SUITED TO THE PREVAILING CONDITIONS. THE NEXT BEST COMBINATION OF REGULATION AND CONTROL TECHNIQUES WAS WIDER LANES ON THE MAIN SHOPPING STREET THROUGH USE OF A NO-STOPPING TOWAWAY REGULATION. TWO OTHER TEST STAGES REVEALED CERTAIN INCREASED EFFICIENCIES IN AREAWIDE MEASURES, BUT, AT THE SAME TIME, REVEALED THE INHERENT PROBLEMS THAT ARISE WHEN ATTEMPTS ARE MADE TO INTRODUCE NEW TRAFFIC PATTERNS WITHOUT HAVING GOOD ALTERNATE ROUTES. THE ASSUMPTION MAY OFTEN BE MADE THAT A CBD SIGNAL SYSTEM IS AT PEAK OPERATING EFFICIENCY AND THAT FURTHER IMPROVEMENTS IN TRAFFIC FLOW CONDITIONS CAN BE MADE ONLY BY IMPLEMENTING MORE RESTRICITIVE TYPES OF CONTROL. THE SIGNAL TIMING SHOULD ALWAYS BE REVIEWED FIRST BECAUSE THIS FACTOR HAS ONE OF THE GREATEST EFFECTS ON INTERSECTION CAPACITY. THIS STUDY SHOWED THAT AREA-WIDE IMPROVEMENTS CAN BE ATTAINED THROUGH SIGNAL TIMING REFINEMENTS. HOWEVER, WHEN TRAFFIC LANES ARE RELATIVELY NARROW AND CURB PARKING IS PRESENT, THE EFFECTS OF SIGNAL TIMING IMPROVEMENTS WERE FOUND TO BE MUCH LESS NOTICEABLE.

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  • Supplemental Notes:
    • Distribution, posting, or copying of this PDF is strictly prohibited without written permission of the Transportation Research Board of the National Academy of Sciences. Unless otherwise indicated, all materials in this PDF are copyrighted by the National Academy of Sciences. Copyright © National Academy of Sciences. All rights reserved. 100 PP, 65 FIG, 34 TAB, 7 REF, 4 APP
  • Authors:
    • Kell, J H
    • JOHNSON, B C
  • Publication Date: 1970

Media Info

  • Media Type: Digital/other
  • Serial:
    • NCHRP Report
    • Issue Number: 110
    • Publisher: Transportation Research Board
    • ISSN: 0077-5614
  • Publication flags:

    Open Access (libre)

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Filing Info

  • Accession Number: 00225939
  • Record Type: Publication
  • Files: TRIS, ATRI
  • Created Date: Apr 18 1971 12:00AM