Comparison of Observed and Predicted Abutment Scour at Selected Bridges in Maine

Maximum abutment-scour depths predicted with five different methods were compared to maximum abutment-scour depths observed at 100 abutments at 50 bridge sites in Maine with a median bridge age of 66 years. Prediction methods included the Froehlich/Hire method, the Sturm method, and the Maryland method published in Federal Highway Administration Hydraulic Engineering Circular 18 (HEC-18); the Melville method; and envelope curves. No correlation was found between scour calculated using any of the prediction methods and observed scour. Abutment scour observed in the field ranged from 0 to 6.8 feet, with an average observed scour of less than 1.0 foot. Fifteen of the 50 bridge sites had no observable scour. Equations frequently overpredicted scour by an order of magnitude and in some cases by two orders of magnitude. The equations also underpredicted scour 4 to 14 percent of the time.

  • Record URL:
  • Corporate Authors:

    U.S. Geological Survey

    26 Ganneston Drive
    Augusta, ME  United States  04333

    Maine Department of Transportation

    Child House, 16 State House Station
    Augusta, ME  United States  04333-0016
  • Authors:
    • Lombard, Pamela J
    • Hodgkins, Glenn A
  • Publication Date: 2008


  • English

Media Info

  • Media Type: Web
  • Edition: Final Report
  • Features: Figures; Maps; Photos; References; Tables;
  • Pagination: 31p

Subject/Index Terms

Filing Info

  • Accession Number: 01153257
  • Record Type: Publication
  • Report/Paper Numbers: Report No. 08-04, SIR 2008-5099
  • Created Date: Mar 25 2010 7:34AM