Research Pays Off: Low-Cost Approach to Reducing Crashes on Multilane Undivided Highways in Louisiana

Undivided highways consistently perform at low levels of safety, particularly in urban and suburban areas. Between 1999 and 2007, several Louisiana Department of Transportation and Development (DOTD) district offices identified the reduction of rear-end crashes on four-lane undivided highways as an urgent need. To meet this need within the available budgets, the district offices received permission to convert several segments of undivided four-lane roadways into five-lane roadways; the center lane served as a two-way left turn lane. The conversion required restriping the pavement markings without increasing the pavement width. In this research, crash modification factors were identified and developed to determine the effectiveness of Louisiana's restriping projects in reducing crashes or crash severity. Six years of crash data from four restriped highway segments was analyzed to compare the three years before and after restriping. On all four segments overall crash rates were reduced. Benefit cost ratios are also discussed in this article.


  • English

Media Info

  • Media Type: Digital/other
  • Features: Figures; Photos; References; Tables;
  • Pagination: pp 43-44
  • Serial:
    • TR News
    • Issue Number: 301
    • Publisher: Transportation Research Board
    • ISSN: 0738-6826
  • Publication flags:

    Open Access (libre)

Subject/Index Terms

Filing Info

  • Accession Number: 01594582
  • Record Type: Publication
  • Files: TRIS, TRB, ATRI
  • Created Date: Mar 24 2016 4:47PM