Techniques for estimating magnitude and frequency of floods for Wisconsin streams

Open-File Report 80-1214
Prepared in cooperation with the Wisconsin Department of Transportation



This report provides improved methods for estimating the magnitude and frequency of floods for Wisconsin streams. Proper design of hydraulic structures and adequate flood-plain management depend on this information. Multiple-regression techniques were used to develop equations for estimating flood frequencies at ungaged sites.

The State is divided into five areas and has equations developed for each area. These areas are based on areal factors determined from previous studies and physical basin characteristics. Significant characteristics in the equations are soil permeability, drainage area, slope, storage, forest cover, snowfall, precipitation intensity, and mean annual precipitation. Standard errors of estimate for the regression equations ranged from 23 to 38 percent.

Annual flood peaks, basin characteristics, and flood-frequency values are presented in this report. Data from 184 gaging stations were used in the regression analysis, of which 20 had rainfall-runoff data collected. Long-term synthetic peaks were generated from the rainfall-runoff data and were weighted with the observed peak data to improve the flood-frequency distributions.

A method to estimate flood-frequency values for regulated streams was developed by discharge-drainage area relationships. Graphs for the major regulated streams are presented in the report.

Study Area

Publication type Report
Publication Subtype USGS Numbered Series
Title Techniques for estimating magnitude and frequency of floods for Wisconsin streams
Series title Open-File Report
Series number 80-1214
DOI 10.3133/ofr801214
Year Published 1981
Language English
Publisher U.S. Geological Survey
Contributing office(s) Wisconsin Water Science Center
Description Report: iv, 116 p.; 3 Plates: 28.00 x 31.00 inches, 27.50 x 31.00 inches, 27.50 x 31.00 inches
Country United States
State Wisconsin
Online Only (Y/N) N
Additional Online Files (Y/N) Y
Google Analytic Metrics Metrics page
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