The Bureau of Engineering and the Department of Traffic implemented the Pavement Grooving Program after studies by the California Division of Highways and others had shown that this pavement treatment significantly reduces the frequency of wet pavement accidents. The initial group of grooving projects was completed in March 1970. Four locations were selected for grooving in the initial group. All were at severe curves on heavily traveled arterial streets and all had a history of correctable accidents, i.e., wet pavement ran-off-road, fixed object, head-on, sideswipe, rear-end, overturned, and parked vehicle. Various patterns of longitudinal grooves have been installed at high accident locations to increase roadway friction. The California State Division of Highways has experimented with pavement grooving on both PCC and AC pavements. Widths and depths of grooves vary from 1/4" to 1/8" and spacing of cuts vary from 3/8" to 1" center to center. Roadways are grooved curb to curb. Results of these tests indicate that grooves 1/8" wide and 1/8" deep are satisfactory. At locations where wider grooves have been used, drivers complain that their vehicles tend to "Track" giving a sensation similar to driving on railroad tracks. An example of wider grooving is on the Hollywood Freeway through the Cahuenga Pass. Depths in excess of 1/8" do not appear justified. Recommendations are that the Pavement Grooving Program be continued on an expanded basis, and that copies of this report be furnished to the Technical Committee for Capital Programming and to the Traffic Committee of the City Council for information.

  • Corporate Authors:

    Los Angeles Department of Traffic

    Bureau of Program Development
    Los Angeles, CA  United States 
  • Authors:
    • Clearwater, L L
    • Clark, N B
    • Jared, W J
    • Taylor, S S
  • Publication Date: 1972-8-10

Media Info

  • Features: Photos; Tables;
  • Pagination: 19 p.

Subject/Index Terms

Filing Info

  • Accession Number: 00260902
  • Record Type: Publication
  • Source Agency: Highway Safety Research Institute
  • Files: TRIS
  • Created Date: Sep 19 1974 12:00AM