Finding and Analyzing True Effect of Non-Recurrent Congestion on Mobility and Safety

This report describes research which examined the causes and impact of non-recurrent congestion. A method is presented which divides the total congestion delay in a freeway section into six components: the delay caused by incidents, special events, lane closures, and adverse weather; the potential reduction in delay at bottlenecks that ideal ramp metering can achieve; and the remaining delay, due mainly to excess demand. The method can be applied to any site with minimum calibration, but it requires data about traffic volume and speed; the time and location of incidents, special events and lane closures; and adverse weather. The method is illustrated by applying it to a 45-mile section of I-880 in the San Francisco Bay Area. Another component of the study involved implementing a simpler method which used routine data collected in the Freeway Performance Measurement System (PeMS). A PeMS application now provides a ‘congestion pie’ for any district or freeway segment. The pie divides the total congestion delay into three categories: potential reduction, excess demand, and accidents; and an unexplained, ‘miscellaneous’, category.

• Record URL:
  • https://merritt.cdlib.org/d/ark%3A%2F13030%2Fm5ks6snw/2/producer%2FPRR-2007-10.pdf
• 
• Availability:
  • Find a library where document is available. Order URL: http://worldcat.org/oclc/173806972
• Corporate Authors:

  University of California, Berkeley

  Berkeley, CA  United States  94720-1720

  University of California, Berkeley

  California PATH Program, Institute of Transportation Studies
  Richmond Field Station, 1357 South 46th Street
  Richmond, CA  United States  94804-4648

  California Department of Transportation

  1120 N Street
  Sacramento, CA  United States  95814
• Authors:
  • Varaiya, Pravin P
• Publication Date: 2007-8

Language

• English

Media Info

• Media Type: Digital/other
• Features: Appendices; References; Tables;
• Pagination: v.p.
• Serial:
  • PATH Research Report
  • Publisher: University of California, Berkeley
  • ISSN: 1055-1425

Subject/Index Terms

• TRT Terms: Loop detectors; Nonrecurrent congestion; Ramp metering; Traffic congestion; Traffic delays; Weather
• Geographic Terms: California
• Subject Areas: Highways; Operations and Traffic Management; I71: Traffic Theory;

Filing Info

• Accession Number: 01080299
• Record Type: Publication
• Source Agency: UC Berkeley Transportation Library
• Report/Paper Numbers: UCB-ITS-PRR-2007-10
• Contract Numbers: TO 5321
• Files: CALTRANS, TRIS, ATRI, STATEDOT
• Created Date: Oct 31 2007 6:38AM