TECHNIQUE FOR ESTIMATING MAGNITUDE AND FREQUENCY OF FLOODS IN ILLINOIS
A technique is presented for estimating flood magnitudes at recurrence intervals ranging from 2 to 500 years, for unregulated rural streams in Illinois, with drainage areas ranging from 0.02 to 10,000 square miles (0.05 to 25,900 square kilometers). Multiple regression analyses, using streamflow data from 241 sampling sites, were used to define the flood-frequency relationships. The independent variables drainage area, slope, rainfall intensity, and an areal factor are used in the estimating equations to determine flood peaks. Examples are given to demonstrate a step-by-step procedure in computing a 100-year flood for a site on an ungaged stream and a site on a gaged stream in Illinois.
- Prepared in cooperation with Illinois State Div. of Highways, Springfield.
U.S. Geological SurveyF Street Between 18th and 19th Street, NW
Washington, DC 20244
Illinois Department of TransportationDivision of Highways, 2300 South Dirksen Parkway
Springfield, IL United States 62764
- Curtis, G W
- Publication Date: 1977-7
- Pagination: 78 p.
- TRT Terms: Drainage; Floods; Flow; Forecasting; Hydrology; Mathematical models; Mathematical prediction; Measurement; Rain; Rainfall; Regression analysis; Runoff; Rural areas; Slopes; Stream gages; Streamflow; Streams; Tables (Data); Watersheds
- Uncontrolled Terms: Rainfall intensity
- Geographic Terms: Illinois
- Subject Areas: Data and Information Technology; Hydraulics and Hydrology; Railroads;
- Accession Number: 00175688
- Record Type: Publication
- Source Agency: National Technical Information Service
- Report/Paper Numbers: USGS/WRD/WRI-78/009 Final Rpt., USGS/WRI-77-117
- Files: TRIS
- Created Date: Jun 28 1978 12:00AM