Developing Inexpensive Crash Countermeasures for Louisiana Local Roads

Although 40% of all crashes in Louisiana are on local roads, local road safety improvement programs have not received the attention needed to reduce crashes. Local road crash countermeasures are an important part of the overall efforts to reduce crashes and their severity in Louisiana. The efforts to develop a local road safety program are hampered by the lack of appropriate risk assessment that enables local agencies to reduce crashes using low cost countermeasures. This paper provides a methodology that can be used by local agencies to deploy countermeasures based on a risk assessment and optimization to meet a fixed budget. First, a statistical model is presented to assess the risk of local road segments taking into account average annual daily travel (AADT) and geometric features of the road segment or intersection. Secondly, low cost countermeasures are recommended for individual road segments and costs for improvements are assessed. Thirdly, a score which allows the ranking of road projects is developed for each road segment. This score incorporates the risk associated with the observed number of crashes, the benefits of improvements, and the total cost of a project. Finally, guidelines for a local road safety improvement program are presented to allow local agencies to institute procedures for a systematic system-wide road improvement methodology. The deliverables include an Excel application that uses online analytical processing (OLAP) to obtain a ranking of candidates for road improvements. This application makes use of crash data, engineering features, and AADT to compute empirical Bayes (EB) estimates and tail probabilities for each road segment and intersection. Road segments and intersections with a tail probability below 5% are selected as candidates for countermeasures. These candidates are evaluated using Google Earth, countermeasures are suggested, and costs and benefits of the countermeasures are obtained using published information. The resulting road improvement projects are then ranked using multi criteria Data Envelopment Analysis (DEA) including costs, benefits and crash risks.

• Record URL:
  http://www.ltrc.lsu.edu/pdf/2014/FR_503.pdf
• 
• Summary URL:
  https://www.ltrc.lsu.edu/pdf/2014/ts_503.pdf
• Corporate Authors:

  Louisiana State University, Baton Rouge

  Louisiana Transportation Research Center
  4101 Gourrier Avenue
  Baton Rouge, LA  United States  70808

  Louisiana Department of Transportation

  P.O. Box 94245
  1201 Capitol Access Road
  Baton Rouge, LA  United States  70804-9245

  Federal Highway Administration

  1200 New Jersey Avenue, SE
  Washington, DC  United States  20590
• Authors:
  • Schneider, Helmut
  • Sun, Xiaoduan
  • Kelle, Peter
• Publication Date: 2014-3

Language

• English

Media Info

• Media Type: Digital/other
• Edition: Final Report
• Features: Appendices; Figures; Photos; References; Tables;
• Pagination: 116p

Subject/Index Terms

• TRT Terms: Annual average daily traffic; Bayes' theorem; Benefit cost analysis; Countermeasures; Crash risk forecasting; Highway safety; Methodology; Risk assessment; Traffic crashes
• Uncontrolled Terms: Local roads
• Geographic Terms: Louisiana
• Subject Areas: Highways; Operations and Traffic Management; Safety and Human Factors; I82: Accidents and Transport Infrastructure;

Filing Info

• Accession Number: 01522374
• Record Type: Publication
• Report/Paper Numbers: FHWA/LA.13/503
• Contract Numbers: LTRC Project Number: 10-5SS; SIO/State Project Num
• Files: TRIS, ATRI, USDOT, STATEDOT
• Created Date: Apr 22 2014 3:04PM