Methods for estimating selected low-flow statistics and development of annual flow-duration statistics for Ohio

Koltun, G. F.; Kula, Stephanie P.

Abstract:

This report presents the results of a study to develop methods for estimating selected low-flow statistics and for determining annual flow-duration statistics for Ohio streams. Regression techniques were used to develop equations for estimating 10-year recurrence-interval (10-percent annual-nonexceedance probability) low-flow yields, in cubic feet per second per square mile, with averaging periods of 1, 7, 30, and 90-day(s), and for estimating the yield corresponding to the long-term 80-percent duration flow. These equations, which estimate low-flow yields as a function of a streamflow-variability index, are based on previously published low-flow statistics for 79 long-term continuous-record streamgages with at least 10 years of data collected through water year 1997. When applied to the calibration dataset, average absolute percent errors for the regression equations ranged from 15.8 to 42.0 percent. The regression results have been incorporated into the U.S. Geological Survey (USGS) StreamStats application for Ohio (http://water.usgs.gov/osw/streamstats/ohio.html) in the form of a yield grid to facilitate estimation of the corresponding streamflow statistics in cubic feet per second. Logistic-regression equations also were developed and incorporated into the USGS StreamStats application for Ohio for selected low-flow statistics to help identify occurrences of zero-valued statistics. Quantiles of daily and 7-day mean streamflows were determined for annual and annual-seasonal (September–November) periods for each complete climatic year of streamflow-gaging station record for 110 selected streamflow-gaging stations with 20 or more years of record. The quantiles determined for each climatic year were the 99-, 98-, 95-, 90-, 80-, 75-, 70-, 60-, 50-, 40-, 30-, 25-, 20-, 10-, 5-, 2-, and 1-percent exceedance streamflows. Selected exceedance percentiles of the annual-exceedance percentiles were subsequently computed and tabulated to help facilitate consideration of the annual risk of exceedance or nonexceedance of annual and annual-seasonal-period flow-duration values. The quantiles are based on streamflow data collected through climatic year 2008.

Genre:

USGS Numbered Series

ProdID:

70043003

Citation Author:

Koltun, G. F.; Kula, Stephanie P.

Citation Contributing Office:

Ohio Water Science Center

Citation Datum:

Citation Day:

Citation Edition:

Citation Editor:

Citation End Page:

195

Citation Issue:

Citation Keywords:

Citation Language:

English

Citation Larger Work Title:

Citation LatN:

42.0

Citation LatS:

38.4

Citation LonE:

-80.52

Citation LonW:

-84.82

Citation Month:

Citation No Pagination:

Citation Number Of Pages:

206

Citation Online Only Flag:

Citation Phsyical Description:

v, 195 p.; Table 2-1

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Citation Public Comments:

Prepared in cooperation with the Ohio Water Development Authority

Citation Publisher:

U.S. Geological Survey

Citation Series:

Scientific Investigations Report

Citation Series Code:

SIR

Citation Series Number:

2012-5138

Citation Search Results Text:

Methods for estimating selected low-flow statistics and development of annual flow-duration statistics for Ohio; 2013; SIR; 2012-5138; Koltun, G. F.; Kula, Stephanie P.

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Citation Volume:

Citation Year:

2013

Type:

citation/reference

Text:

Methods for estimating selected low-flow statistics and development of annual flow-duration statistics for Ohio; 2013; SIR; 2012-5138; Koltun, G. F.; Kula, Stephanie P.