ASSESSMENT OF COMMONLY USED METHODS OF ESTIMATING FLOOD FREQUENCY

A study made to determine what are likely to be the most accurate and consistent procedures for determining peak flood flow frequencies for ungaged watersheds in the Tennessee Valley region is described. The study was based on information developed during a pilot test, which is currently the most comprehensive and objective method available of examining the performance of commonly used procedures for estimating peak flow frequencies at ungaged locations. Test results showed significant differences in performance when procedures were evaluated by using the criteria of accuracy, reproducibility, and practicality. Although the pilot test evaluation was limited to the Midwest and Northwest, it is concluded that the observed differences in performance result from fundamental differences in procedure formulation that can be expected to occur in the Tennessee Valley and in other regions as well. The most accurate and reproducible procedures evaluated were found to be regression-based procedures in which prediction equations are calibrated to flood-frequency determinations at gaged locations by using statistical estimating procedures. The most obvious reasons for this superior performance are the definition of the parameters and the formulation of the prediction equation. The procedures that performed best (a) used parameters that were well-defined and could be consistently determined, (b) were formulated so that the flood-frequency estimates were not sensitive to parameter variations, and (c) were calibrated to a large number of gage records in a relatively small, well-defined hydrologic region. (Author)

Media Info

  • Media Type: Print
  • Features: Figures; References; Tables;
  • Pagination: pp 10-30
  • Monograph Title: Hydrology and hydraulics: water, noise and air quality
  • Serial:

Subject/Index Terms

Filing Info

  • Accession Number: 00373403
  • Record Type: Publication
  • ISBN: 0309035082
  • Files: TRIS, TRB
  • Created Date: Jun 30 1983 12:00AM