U.S. Department of the Interior

U.S. Geological Survey

Prepared in cooperation with the Ohio Water Development Authority

Methods for Estimating Selected Low-Flow Statistics and 

Development of Annual Flow-Duration Statistics for Ohio

Scientific Investigations Report 2012–5138
Cover. Stream channel during low-flow conditions on Big Walnut Creek at Sunbury, Ohio. (Rendering based on original photograph by 

Al Dillenburg, U.S. Geological Survey.)
Methods for Estimating Selected Low-Flow 

Statistics and Development of Annual 

Flow-Duration Statistics for Ohio

By G.F. Koltun and Stephanie P. Kula

Prepared in cooperation with the Ohio Water Development Authority

Scientific Investigations Report 2012–5138

U.S. Department of the Interior

U.S. Geological Survey

U.S. Department of the Interior
KEN SALAZAR, Secretary

U.S. Geological Survey

Marcia K. McNutt, Director

U.S. Geological Survey, Reston, Virginia: 2013

For more information on the USGS—the Federal source for science about the Earth,

its natural and living resources, natural hazards, and the environment—visit 

http://www.usgs.gov or call 1–888–ASK–USGS

For an overview of USGS information products, including maps, imagery, and publications,

visit http://www.usgs.gov/pubprod

To order this and other USGS information products, visit http://store.usgs.gov

Any use of trade, product, or firm names is for descriptive purposes only and does not imply 

endorsement by the U.S. Government.

Although this report is in the public domain, permission must be secured from the individual 

copyright owners to reproduce any copyrighted material contained within this report.

Suggested citation:

Koltun, G.F., and Kula, S.P., 2013, Methods for estimating selected low-flow statistics and development of annual 

flow-duration statistics for Ohio: U.S. Geological Survey Scientific Investigations Report 2012–5138, 195 p.
iii

Contents

Abstract...........................................................................................................................................................1

Introduction.....................................................................................................................................................1

Purpose and Scope .......................................................................................................................................2

Previous Studies ............................................................................................................................................2

Sources of Low-Flow Statistics and Flow-Duration Data.......................................................................2

Methods for Estimating Low-Flow Statistics ...........................................................................................2

Selection of Explanatory Variables....................................................................................................2

Data Used in Streamflow-Variability Index (SVI) Related Analyses ............................................7

Estimating SVI at Ungaged Sites........................................................................................................7

Errors Associated with Estimating SVI at Ungaged Sites..............................................................8

Equations for Estimating Low-Flow Yield Statistics as a Function of SVI ...................................8

Model Error for Low-Flow-Yield Statistic Estimation Equations.................................................11

Logistic-Regression Equations for Identification of Zero-Valued Low-Flow Statistics ..........12

Limitations of the Estimating Equations ..........................................................................................13

Methods for Annual Flow-Duration Analyses.........................................................................................14

Results and Discussion of Annual Flow-Duration Analyses ................................................................16

Summary........................................................................................................................................................19

References Cited..........................................................................................................................................19

Appendix 1. Miscellaneous Supporting Data ......................................................................................21

Appendix 2. Basin Characteristics Tested for Use in Low-Flow Regression Analyses 

in Ohio ..................................................................................................................................27

Appendix 3. Annual 1-Day and 7-Day Mean Flow-Duration Results for Sites with 

Streamflows that have No or Minimal Regulation........................................................31

Appendix 4. Annual Seasonal-Period Flow-Duration Results for Sites with Streamflows 

that have No or Minimal Regulation ...............................................................................99

Appendix 5. Annual 1-Day and 7-Day Mean Flow-Duration Results for Sites with 

Streamflows that are Subject to Regulation................................................................135

Appendix 6. Annual Seasonal-Period Flow-Duration Results for Sites with Streamflows 

that are Subject to Regulation .......................................................................................175

Figures

1. Graph showing plot of streamflow-variability index as a function of 7-day, 

10-year low-flow yield..................................................................................................................6

2. Map showing spatial distribution of streamflow-variability index values 

determined from streamflow records for streamgages in Ohio and nearby 

portions of adjacent States.........................................................................................................6

3. Generalized map of Ohio showing estimated spatial variation in streamflowvariability index .............................................................................................................................8

4. Boxplot showing streamflow-variability index residuals from the leave-one-out 

cross-validation analysis.............................................................................................................9

5. Graph showing plot of the standard deviation of logarithms of annual 7-day, 

10-year low-flow values as a function of years of streamgage record.............................10
iv

6. Graph showing plot of 7-day, 10-year low-flow yield as a function of streamflowvariability index, illustrating fit of the constrained polynomial equation...........................10

7. Map showing low-flow regions used in regression equations for Q90,10m, and 

D80m .............................................................................................................................................12

8. Graphs illustrating the process used to compute selected quantiles of the a

nnual qp series.............................................................................................................................15

9. Map showing locations of streamflow-gaging stations with annual flow-duration 

analyses that have no or minimal streamflow regulation....................................................17

10. Map showing locations of streamflow-gaging stations with annual flow-duration 

analyses that have streamflows that are subject to appreciable regulation...................18

1-1. Scatter plots of regression residuals as a function of predicted low-flow yields...........26

Tables

1. Data used to develop equations for estimating selected low-flow yield statistics for 

Ohio.—Continued .........................................................................................................................3

2. Equations for estimating selected low-flow yield statistics for Ohio. .................................9

3. Logistic-regression equations for estimating the annual probability of zero flow for 

selected 

low-flow statistics for unregulated streams in Ohio.............................................................13

1-1. Streamflow-variability index (SVI) values for locations in Ohio and adjacent States used 

for SVI-related analyses............................................................................................................21

2–1. Basin characteristics determined for selected streamgages in Ohio and adjacent 

States..................................................................................................Available in Excel format.
v

Conversion Factors

Inch/Pound to SI

Multiply By To obtain

Length

inch (in.) 2.54 centimeter (cm)

centimeter (cm) 0.3937 inch (in.)

inch (in.) 25.4 millimeter (mm)

foot (ft) 0.3048 meter (m)

mile (mi) 1.609 kilometer (km)

Area

square foot (ft2

) 929.0 square centimeter (cm2)

square foot (ft2

) 0.09290 square meter (m2)

square mile (mi2

) 259.0 hectare (ha)

square mile (mi2

) 2.590 square kilometer (km2) 

Flow rate

cubic foot per second (ft3

/s) 0.02832 cubic meter per second (m3/s)

cubic foot per second per square mile 

[(ft3

/s)/mi2]

 0.01093 cubic meter per second per square 

kilometer [(m3/s)/km2]

Hydraulic gradient

foot per mile (ft/mi) 0.1894 meter per kilometer (m/km)

Temperature in degrees Fahrenheit (°F) may be converted to degrees Celsius (°C) as follows:

°C=(°F-32)/1.8

Horizontal coordinate information is referenced to the North American Datum of 1983 (NAD 83).

A climatic year is defined as the 12-month period from April 1 to March 31 and is designated by 

the calendar year in which it ends.

A water year is the 12-month period from October 1 through September 30 and is designated by 

the calendar year in which it ends.

Abbreviations

APE average absolute percent error

APEE annual percentage equaled or exceeded

ESRI Environmental Systems Research Institute

FDC flow-duration curves

HUC hydrologic unit code

IDW inverse-distance weighted

LCTR long-term continuous record

LFPR low-flow partial record

SAS Statistical Analysis System

SVI streamflow-variability index

USGS U.S. Geological Survey

WLS weighted least squares

Methods for Estimating Selected Low-Flow Statistics and 

Development of Annual Flow-Duration Statistics for Ohio

By G.F. Koltun and Stephanie P. Kula

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 annualnonexceedance 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 streamflowvariability 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 streamflowgaging 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.

Introduction

To address the needs for estimating low-flow statistics 

at ungaged locations in Ohio and for stochastically relevant 

annual flow-duration statistics, a study was conducted by 

the U.S. Geological Survey (USGS), in cooperation with the 

Ohio Water Development Authority, to develop methods for 

estimating selected low-flow statistics with regulatory significance1

 and to compute and report stochastically relevant 

annual flow-duration statistics for Ohio streams.

Streamflow statistics are used for a variety of purposes. 

Among other uses, both low-flow and flow-duration statistics 

are particularly useful for making decisions about the suitability of a stream to act as an industrial or public water 

supply or as a suitable destination for waste effluents. These 

suitability questions frequently hinge on the impact of these 

uses on aquatic biota in the affected streams; thus, the statistics that have been adopted for regulatory purposes typically 

are biologically relevant. In spite of the widespread need for 

such statistics, the streamflow data required to compute these 

statistics have been collected only at a small number of locations in Ohio. Consequently, it is important that streamflow 

statistics be determined for gaged locations and that, whenever 

possible, suitable methods are developed to permit estimation 

of those statistics at ungaged locations. 

Traditional flow-duration curves (FDCs) show the 

percentage of time that daily mean streamflow of a given 

magnitude was equaled or exceeded over a long period of time 

(many years). While traditional FDCs provide useful information about long-term streamflow exceedance characteristics, 

their utility is diminished when trying to answer questions 

about exceedance characteristics within a typical year. Another 

drawback of traditional FDCs is that they are not appropriate 

for extracting stochastic hydrologic information to address 

water-resources problems (Sugiyama and others, 2003).

1

For the purposes of this report, regulatory-significant statistics are defined 

as those statistics that are used by regulators because of legal mandate or 

because of recommended best-management practices.
2 Methods for Estimating Selected Low-Flow Statistics and Development of Annual Flow-Duration Statistics for Ohio

Purpose and Scope

The purpose of this report is to (1) describe analytical 

methods and resulting equations for estimating 10-percent 

annual-nonexceedance probability of the 1-, 7-, 30-, and 

90-day low-flow yields and 80-percent flow-duration yield and 

(2) describe methods used to compute annual flow-durationfrequency statistics for selected streamgages in Ohio and 

present the computed annual and annual-seasonal period flowduration frequency statistics. Information is provided to help 

the reader evaluate the accuracy and limitations of the regression equations, which have been incorporated into the USGS 

StreamStats application for Ohio (Koltun and others, 2006).

Previous Studies

Previous studies that produced regression equations for 

estimating one or more low-flow statistics for Ohio streams 

include those by Koltun and Whitehead (2002) and Koltun and 

Schwartz (1987). This report updates equations for estimating 

two of the low-flow statistics (the 7-day, 10-year and 30-day, 

10-year low flows) presented by Koltun and Schwartz (1987) 

and includes equations for additional low-flow statistics 

(the 1-day, 10-year and 90-day, 10-year low flows, and the 

80-percent duration streamflow) that were not addressed in 

either study. 

Sources of Low-Flow Statistics and 

Flow-Duration Data

Regression equations presented in this report are based on 

low-flow and duration statistics for selected Ohio streamgages 

with 10 or more years of record as reported by Straub (2001). 

The low-flow statistics and flow-duration characteristics 

reported by Straub (2001) were based on streamflow data 

collected through water year 1997. In contrast to the longterm flow-duration characteristics reported by Straub (2001), 

this report presents annual flow-duration characteristics in a 

stochastic framework based on a new analysis of daily streamflow data from streamgages with a minimum of 20 years of 

record. 

Methods for Estimating Low-Flow 

Statistics 

Equations for estimating low-flow statistics frequently 

are developed by means of regression techniques employing 

basin and (or) climatic characteristics as explanatory variables. 

Forty-three potential explanatory variables2

 were determined for this study and plotted against low-flow statistics 

and low-flow yields computed from long-term streamflow 

records to assess the nature and strength of covariate relations. 

Correlation and regression analyses were used to supplement the plots and explore secondary and interaction effects 

between explanatory variables.

Selection of Explanatory Variables

Ultimately, relations between a streamflow-variability 

index (SVI) and low-flow yields (that is, the low flow with a 

D-day averaging period, and a T-year recurrence interval, in 

cubic feet per second, divided by the drainage area, in square 

miles) were found to be much stronger than any other covariate relations. SVI is a measure of the variability in streamflow 

resulting from variability in precipitation as mitigated by 

characteristics of the basin such as surface storage and groundwater discharge. All other things being equal, unregulated 

streams with relatively small SVIs tend to have proportionally 

more flow contributed from groundwater discharge (and (or) 

surface storage) than streams with larger SVIs (Searcy, 1959). 

The SVI is defined as the standard deviation of the logarithms of the 19 streamflow values at 5-percent class intervals 

from 5 to 95 percent on the daily flow-duration curve for the 

analysis period (Searcy, 1959). The formula for the SVI discussed in this report is

SVI

D D i i = − ∑ = (log ( ) log ( )) , 10 10

2

5 5

95

18 (1)

where

SVI is the streamflow-variability index, 

Di is the ith percent duration streamflow (i=5, 10, 

15, ... 95), and log ( ) 10 D is the mean of the base 10 logarithms of the 

19 streamflow values at 5-percent class 

intervals from 5 to 95 percent on the flowduration curve of daily mean streamflows. 

In those rare cases where Di = 0, a value of 0.001 was substituted and the resulting SVI was considered less well defined. 

Low-flow yield variables are identified in this document by the 

addition of an “m” to the low-flow statistic name (for example, 

the7-day, 10-year low-flow (Q7,10) yield is referred to as 

Q7,10m).

2

All the potential explanatory variables considered for this study—grouped 

into major categories of land cover, surficial soils and geology, climate, basin 

and channel morphology, hydrogeology, and streamflow variability—are 

discussed in appendix 2.
Methods for Estimating Low-Flow Statistics 

3

Table 1. Data used to develop equations for estimating selected low-flow yield statistics for Ohio.—Continued[mi2, square mile; ft3/s, cubic foot per second; Q1,10m, 1-day, 10-year low-flow yield; Q7,10m, 7-day, 10-year low-flow yield; Q30,10m, 30-day, 10-year low-flow yield; Q90,10m, 90-day, 10-year low-flow 

yield; D80m, 80-percent duration streamflow yield; SVI, streamflow-variability index; yields and SVIs computed based on statistics reported by Straub (2001)]

Station 

number Station name Decimal latitude Decimal longitude

Drainage 

area from 

StreamStats (mi2)

Region 

code

Streamflowvariability 

index 

(log10(ft3/s))

Q1,10m 

[(ft3/s)/mi2]

Q7,10m 

[(ft3/s)/mi2]

Q30,10m 

[(ft3/s)/mi2]

Q90,10m 

[(ft3/s)/mi2]

D80m 

[(ft3/s)/mi2]

03089500 Mill Creek near Berlin Center, Ohio 41.0003 −80.9684 19.13 A 0.6880 0.0000 0.0000 0.0052 0.0157 0.0366

03092000 Kale Creek near Pricetown, Ohio 41.1398 −80.9951 21.68 A 0.8076 0.0000 0.0000 0.0046 0.0092 0.0277

03092090 West Branch Mahoning River near 

Ravenna, Ohio

41.1614 −81.1970 21.81 A 0.5068 0.0138 0.0229 0.0550 0.1101 0.1697

03102950 Pymatuning Creek at Kinsman, Ohio 41.4428 −80.5881 96.62 B 0.6267 0.0021 0.0041 0.0145 0.0466 0.1242

03109500 Little Beaver Creek near East Liverpool, 

Ohio

40.6759 −80.5406 495.57 B 0.4812 0.0363 0.0404 0.0565 0.0848 0.1655

03110000 Yellow Creek near Hammondsville, Ohio 40.5378 −80.7251 147.22 B 0.5439 0.0122 0.0149 0.0265 0.0557 0.1359

03111500 Short Creek near Dillonvale, Ohio 40.1934 −80.7342 122.95 B 0.3795 0.0586 0.0740 0.1057 0.1545 0.2684

03111548 Wheeling Creek below Blaine, Ohio 40.0670 −80.8084 97.60 B 0.3280 0.0932 0.1014 0.1230 0.2152 0.3689

03114000 Captina Creek at Armstrongs Mills, Ohio 39.9087 −80.9240 133.69 B 0.6797 0.0000 0.0000 0.0037 0.0254 0.0972

03115400 Little Muskingum River at Bloomfield, 

Ohio

39.5631 −81.2037 209.94 B 0.7516 0.0010 0.0014 0.0033 0.0152 0.0714

03115500 Little Muskingum River at Fay, Ohio 39.4801 −81.2857 258.25 B 0.7834 0.0000 0.0000 0.0023 0.0213 0.0542

03117500 Sandy Creek at Waynesburg, Ohio 40.6726 −81.2598 253.15 B 0.4399 0.0672 0.0711 0.0869 0.1067 0.2054

03123000 Sugar Creek above Beach City Dam at 

Beach City, Ohio

40.6567 −81.5768 159.99 B 0.5406 0.0156 0.0188 0.0300 0.0456 0.0938

03130500 Touby Run at Mansfield, Ohio 40.7648 −82.5452 5.48 A 0.5120 0.0000 0.0183 0.0365 0.0730 0.1096

03134000 Jerome Fork at Jeromeville, Ohio 40.8020 −82.2002 120.01 A 0.5689 0.0175 0.0208 0.0325 0.0483 0.0683

03139000 Killbuck Creek at Killbuck, Ohio 40.4815 −81.9860 463.22 A 0.4484 0.0648 0.0669 0.0799 0.0993 0.1727

03140000 Mill Creek near Coshocton, Ohio 40.3628 −81.8624 27.22 A 0.6403 0.0037 0.0037 0.0073 0.0220 0.0808

03144000 Wakatomika Creek near Frazeysburg, Ohio 40.1326 −82.1479 140.14 B 0.5223 0.0257 0.0285 0.0385 0.0592 0.1284

03146000 North Fork Licking River at Utica, Ohio 40.2281 −82.4515 116.26 B 0.5981 0.0138 0.0181 0.0275 0.0439 0.0860

03149500 Salt Creek near Chandlersville, Ohio 39.9087 −81.8604 75.55 B 0.6552 0.0000 0.0013 0.0093 0.0529 0.0715

03156000 Hunters Run at Lancaster 39.7085 −82.6221 10.13 B 0.4223 0.0296 0.0395 0.0790 0.0987 0.1875

03157000 Clear Creek near Rockbridge, Ohio 39.5884 −82.5785 88.83 B 0.3758 0.0901 0.1036 0.1238 0.1576 0.2364

03157500 Hocking River at Enterprise, Ohio 39.5651 −82.4746 458.38 B 0.4455 0.0654 0.0698 0.0829 0.1047 0.1745

03159540 Shade River near Chester, Ohio 39.0637 −81.8818 154.60 B 0.6870 0.0026 0.0032 0.0058 0.0175 0.0712

03201600 Sandy Run at Big Four Hollow Creek 

near Lake Hope, Ohio

39.3626 −82.3129 0.97 B 0.5812 0.0000 0.0000 0.0000 0.1031 0.1031
4 Methods for Estimating Selected Low-Flow Statistics and Development of Annual Flow-Duration Statistics for Ohio Table 1. Data used to develop equations for estimating selected low-flow yield statistics for Ohio.—Continued [mi2, square mile; ft3/s, cubic foot per second; Q1,10m, 1-day, 10-year low-flow yield; Q7,10m, 7-day, 10-year low-flow yield; Q30,10m, 30-day, 10-year low-flow yield; Q90,10m, 90-day, 10-year low-flow yield; D80m, 80-percent duration streamflow yield; SVI, streamflow-variability index; yields and SVIs computed based on statistics reported by Straub (2001)] Station number Station name Decimal latitude Decimal longitude Drainage area from Stream- Stats (mi2

)

Region 

code

Streamflowvariability 

index 

(log10(ft3/s))

Q1,10m 

[(ft3/s)/mi2

]

Q7,10m 

[(ft3/s)/mi2

]

Q30,10m 

[(ft3/s)/mi2

]

Q90,10m 

[(ft3/s)/mi2

]

D80m 

[(ft3/s)/mi2

]

03201700 Big Four Hollow Creek near Lake Hope, 

Ohio

39.3634 −82.3140 1.01

B 0.6225 0.0000 0.0000 0.0000 0.0000 0.0991

03202000 Raccoon Creek at Adamsville, Ohio 38.8756 −82.3561 584.51

B 0.6549 0.0056 0.0068 0.0103 0.0205 0.0838

03217500 Scioto River at Larue, Ohio 40.5719 −83.3842 257.43

A 0.6639 0.0101 0.0120 0.0151 0.0218 0.0466

03218000 Little Scioto River above Marion, Ohio 40.6287 −83.1696 72.32

A 1.0080 0.0000 0.0000 0.0000 0.0000 0.0083

03219500 Scioto River near Prospect, Ohio 40.4195 −83.1971 567.60

A 0.6391 0.0132 0.0169 0.0194 0.0264 0.0511

03223000 Olentangy River at Claridon, Ohio 40.5828 −82.9888 156.94

A 0.6810 0.0013 0.0019 0.0045 0.0166 0.0554

03224500 Whetstone Creek near Ashley, Ohio 40.4551 −82.9577 98.34

A 0.6184 0.0020 0.0020 0.0061 0.0264 0.0702

03230500 Big Darby Creek at Darbyville, Ohio 39.7006 −83.1102 533.76

A 0.5832 0.0096 0.0114 0.0178 0.0281 0.0768

03230800 Deer Creek at Mount Sterling, Ohio 39.7151 −83.2571 228.07

A 0.5002 0.0267 0.0338 0.0425 0.0658 0.1491

03232000 Paint Creek near Greenfield, Ohio 39.3792 −83.3755 248.97

B 0.7421 0.0008 0.0012 0.0036 0.0084 0.0442

03235000 Salt Creek at Tarlton, Ohio 39.5556 −82.7807 11.50

A 0.7962 0.0000 0.0000 0.0000 0.0000 0.0261

03236000 Salt Creek near Londonderry, Ohio 39.2562 −82.7699 285.66

A 0.6001 0.0196 0.0214 0.0280 0.0455 0.0770

03237280 Upper Twin Creek at McGaw, Ohio 38.6437 −83.2157 12.18

B 0.9206 0.0000 0.0000 0.0000 0.0082 0.0246

03237500 Ohio Brush Creek near West Union, Ohio 38.8037 −83.4210 386.98

B 0.7881 0.0008 0.0008 0.0023 0.0088 0.0413

03238500 White Oak Creek near Georgetown, Ohio 38.8581 −83.9285 217.82

B 0.8185 0.0000 0.0000 0.0005 0.0087 0.0335

03240000 Little Miami River near Oldtown, Ohio 39.7484 −83.9313 128.99

A 0.4092 0.0535 0.0667 0.0760 0.0930 0.1938

03240500 North Fork Massie Creek at Cedarville, 

Ohio

39.7570 −83.7902 28.91

A 0.5796 0.0000 0.0000 0.0069 0.0242 0.0865

03241000 South Fork Massie Creek near Cedarville, 

Ohio

39.7389 −83.7638 17.03

A 0.7273 0.0000 0.0000 0.0059 0.0117 0.0470

03241500 Massies Creek at Wilberforce, Ohio 39.7228 −83.8827 63.36

A 0.5144 0.0189 0.0221 0.0316 0.0458 0.1294

03242050 Little Miami River near Spring Valley, Ohio 39.5834 −84.0302 366.33

A 0.3232 0.0901 0.0983 0.1201 0.1419 0.3576

03242200 Anderson Fork near New Burlington, Ohio 39.5664 −83.9027 77.82

A 0.6689 0.0039 0.0039 0.0064 0.0141 0.0861

03246200 East Fork Little Miami River near 

Marathon, Ohio

39.1145 −84.0247 194.80

A 0.6760 0.0036 0.0041 0.0067 0.0308 0.0719

03246500 East Fork Little Miami River at 

Williamsburg, Ohio

39.0526 −84.0505 236.61

A 0.8812 0.0000 0.0000 0.0004 0.0025 0.0232

03260800 Stony Creek near De Graff, Ohio 40.2909 −83.9099 59.09

A 0.3583 0.1032 0.1083 0.1218 0.1354 0.2369

03265000 Stillwater River at Pleasant Hill, Ohio 40.0578 −84.3561 505.02

A 0.5207 0.0160 0.0257 0.0337 0.0475 0.1030

03266000 Stillwater River at Englewood, Ohio 39.8703 −84.2861 651.03

A 0.5325 0.0169 0.0246 0.0338 0.0476 0.1029
Methods for Estimating Low-Flow Statistics 

5

Table 1. Data used to develop equations for estimating selected low-flow yield statistics for Ohio.—Continued[mi2, square mile; ft3/s, cubic foot per second; Q1,10m, 1-day, 10-year low-flow yield; Q7,10m, 7-day, 10-year low-flow yield; Q30,10m, 30-day, 10-year low-flow yield; Q90,10m, 90-day, 10-year low-flow 

yield; D80m, 80-percent duration streamflow yield; SVI, streamflow-variability index; yields and SVIs computed based on statistics reported by Straub (2001)]

Station 

number Station name Decimal latitude Decimal longitude

Drainage 

area from 

StreamStats (mi2)

Region 

code

Streamflowvariability 

index 

(log10(ft3/s))

Q1,10m 

[(ft3/s)/mi2]

Q7,10m 

[(ft3/s)/mi2]

Q30,10m 

[(ft3/s)/mi2]

Q90,10m 

[(ft3/s)/mi2]

D80m 

[(ft3/s)/mi2]

03266500 Mad River at Zanesfield, Ohio 40.3503 −83.6744 7.29 A 0.4024 0.0960 0.0960 0.1235 0.1372 0.2195

03267000 Mad River near Urbana, Ohio 40.1076 −83.7991 162.60 A 0.2527 0.2030 0.2153 0.2337 0.2583 0.3998

03268000 Buck Creek at New Moorefield, Ohio 39.9920 −83.7146 64.56 A 0.2428 0.2169 0.2324 0.2633 0.3098 0.4182

03270800 Wolf Creek at Trotwood, Ohio 39.7942 −84.3099 22.85 A 0.6437 0.0000 0.0044 0.0088 0.0219 0.0700

03271000 Wolf Creek at Dayton, Ohio 39.7667 −84.2366 68.79 A 0.4940 0.0189 0.0233 0.0334 0.0494 0.1119

03271800 Twin Creek near Ingomar, Ohio 39.7078 −84.5249 197.44 A 0.5738 0.0177 0.0198 0.0233 0.0324 0.0861

03272000 Twin Creek near Germantown, Ohio 39.6378 −84.4038 275.54 A 0.5765 0.0149 0.0171 0.0225 0.0323 0.0835

03272700 Sevenmile Creek at Camden, Ohio 39.6292 −84.6444 68.97 A 0.5601 0.0189 0.0218 0.0305 0.0479 0.0986

03272800 Sevenmile Creek at Collinsville, Ohio 39.5231 −84.6108 120.35 A 0.5782 0.0141 0.0166 0.0199 0.0266 0.0706

04184500 Bean Creek at Powers, Ohio 41.6595 −84.2491 206.04 A 0.4950 0.0345 0.0379 0.0466 0.0582 0.1165

04185440 Unnamed Tributary to Lost Creek near 

Farmer, Ohio

41.3617 −84.6911 4.52 A 0.8249 0.0000 0.0000 0.0000 0.0000 0.0221

04188500 Eagle Creek near Findlay, Ohio 40.9931 −83.6513 54.32 A 1.1227 0.0000 0.0000 0.0000 0.0000 0.0037

04189500 Blanchard River at Glandorf, Ohio 41.0445 −84.0819 644.55 A 0.6714 0.0085 0.0123 0.0202 0.0341 0.0543

04196500 Sandusky River near Upper Sandusky, Ohio 40.8506 −83.2563 295.51 A 0.6602 0.0044 0.0058 0.0095 0.0190 0.0474

04197000 Sandusky River near Mexico, Ohio 41.0442 −83.1949 773.79 A 0.6370 0.0072 0.0100 0.0155 0.0233 0.0504

04197100 Honey Creek at Melmore, Ohio 41.0223 −83.1096 149.31 A 0.7650 0.0013 0.0020 0.0033 0.0087 0.0335

04197170 Rock Creek at Tiffin, Ohio 41.1137 −83.1683 34.50 A 0.5533 0.0145 0.0174 0.0203 0.0290 0.0638

04198000 Sandusky River near Fremont, Ohio 41.3078 −83.1588 1250.93 A 0.6439 0.0088 0.0104 0.0152 0.0232 0.0496

04198500 East Branch Huron River near Norwalk, 

Ohio

41.2495 −82.6477 85.35 A 0.5672 0.0047 0.0070 0.0141 0.0281 0.0668

04199000 Huron River at Milan, Ohio 41.3009 −82.6082 370.23 A 0.5820 0.0113 0.0135 0.0194 0.0324 0.0675

04199500 Vermilion River near Vermilion, Ohio 41.3820 −82.3168 261.64 A 0.7656 0.0004 0.0004 0.0015 0.0076 0.0363

04200000 East Branch Black River at Elyria, Ohio 41.3475 −82.0943 216.64 A 0.9035 0.0000 0.0000 0.0005 0.0023 0.0171

04209000 Chagrin River at Willoughby, Ohio 41.6309 −81.4034 247.04 B 0.4267 0.0445 0.0567 0.0850 0.1174 0.2348

04210000 Phelps Creek near Windsor, Ohio 41.5156 −80.9351 25.50 B 0.7352 0.0039 0.0078 0.0157 0.0196 0.0471

04212000 Grand River near Madison, Ohio 41.7406 −81.0465 580.31 B 0.8020 0.0007 0.0016 0.0050 0.0119 0.0362

04212100 Grand River near Painesville, Ohio 41.7189 −81.2279 684.47 B 0.6330 0.0121 0.0131 0.0219 0.0526 0.1315

04212500 Ashtabula River near Ashtabula, Ohio 41.8556 −80.7620 120.43 B 1.0617 0.0000 0.0000 0.0000 0.0017 0.0216

04213000 Conneaut Creek at Conneaut, Ohio 41.9270 −80.6040 175.99 B 0.6263 0.0085 0.0125 0.0233 0.0398 0.1250
6 Methods for Estimating Selected Low-Flow Statistics and Development of Annual Flow-Duration Statistics for Ohio

Figure 1. Graph showing plot of 

streamflow-variability index as a 

function of 7-day, 10-year low-flow 

yield.

Figure 2. Map showing spatial 

distribution of streamflow-variability 

index values determined from 

streamflow records for streamgages in 

Ohio and nearby portions of adjacent 

States (LTCR, long-term continuous 

record; LFPR, low-flow partial record).
Methods for Estimating Low-Flow Statistics 7

Data Used in Streamflow-Variability Index (SVI)

Related Analyses

A variety of data sources were used to examine the 

relation between SVI and low-flow statistics and to facilitate 

the estimation of SVI at ungaged sites. SVIs were obtained, 

computed, or estimated for a total of 162 sites (see appendix 1). 

Of those 162 sites, 121 were long-term continuous record 

(LTCR) sites with 10 or more years of record (93 in Ohio, 

11 in Indiana, 6 in Kentucky, 6 in West Virginia, 3 in Michigan, 

and 2 in Pennsylvania) and 41 were low-flow partial record3

(LFPR) sites located in Ohio with published low-flow statistics. 

SVIs for LTCR and LFPR sites in Ohio are based on the lowflow statistics and periods of record published in Straub (2001). 

SVIs for LTCR sites in Indiana, Kentucky, West Virginia, 

Michigan, and Pennsylvania were either provided by the USGS 

Water Science Center in that State (in the cases of Indiana, 

Kentucky, and West Virginia) or were computed from approved 

streamflow records or statistics (in the cases of Michigan and 

Pennsylvania). As noted in subsequent discussions, subsets of 

the 162 site SVI dataset were used for some analyses.

Estimating SVI at Ungaged Sites

SVI must be regionalized in some fashion to permit its 

estimation at ungaged sites. Koltun and Whitehead (2002) 

developed a generalized grid-based spatial coverage of SVI for 

Ohio that they used for that purpose. SVI was used by Koltun 

and Whitehead (2002) as an explanatory variable in equations they developed to estimate June–October mean monthly 

streamflows; the 25th-, 50th-, and 75th-percentile streamflows; 

and the harmonic mean streamflow. For this study, a new SVI

grid coverage was created that is more spatially refined and 

reflects at-site SVI information from more streamgages than 

the coverage developed by Koltun and Whitehead (2002). 

The geostatistical techniques of kriging and cokriging 

were both examined as possible mechanisms for regionalizing SVI; however, a lack of wide-sense stationarity in SVI

(possibly owing to localized hydrogeologic features that are 

poorly represented by available covariate datasets) made those 

methods unsuitable. This result is consistent with similar 

findings from a recent study by Martin and Arihood (2010) in 

which they observed LTCR streamgage data from Kentucky 

often indicated a change in SVI values even though lithologic 

characteristics of surface geology did not change. They further 

concluded that specific lithologies did not necessarily result in 

consistent effects on groundwater discharge and low flow. 

Examination of semivariogram plots (not shown) 

prepared when exploring options for kriging and cokriging 

indicated that sites that are closer together tend to have more 

3

Low-flow partial record (LFPR) sites are sites where periodic low-flow 

measurements are made for the purpose of developing a statistical relation 

with concurrent low flows at a long-term continuous record (LTCR) site. That 

statistical relation is used to estimate low-flow statistics for the LFPR site as a 

function of low-flow statistics computed for the LTCR site.

similar SVI values than sites that are further apart. Consequently, the decision was made to develop a spatial grid of 

SVI by use of an inverse-distance-weighted (IDW) interpolation (Environmental Systems Research Institute, 2008) of 

the point SVI data. The IDW model, as applied, assumes that 

observations further away from a given location have their 

contributions to its spatial average reduced as a function of the 

square of the distance from that location. The IDW interpolation, which was based on the 12 nearest neighbors (in this 

case, sites with defined SVIs) to each 1 square kilometer (km2) 

grid cell, was done with the Environmental Systems Research 

Institute (ESRI) Spatial Analyst software.

To prepare the SVI grid, LTCR sites (sites with 10 or 

more years of daily record) were selected from Ohio that were 

thought to be predominately free of low-flow regulation (that 

is, they had no significant regulation from upstream dams or 

other controlled lakes, and no significant low-flow regulation 

from water-supply withdrawals or wastewater discharges), 

along with comparable LTCR sites from adjacent States that 

were located near the State border of Ohio. SVIs determined 

from long-term streamflow records for the LTCR sites initially 

were plotted on a map (not shown) to assess spatial trends. 

Although there were visually identifiable spatial trends (for 

example a cluster of low SVIs at streamgages in a watershed 

known for relatively high groundwater discharge), it was 

apparent that, in some areas, SVIs can change appreciably 

over relatively short distances. Consequently, it was deemed 

important to obtain and use as much SVI data as possible to 

prepare the grid. 

Since SVI was strongly related to the target low-flow 

statistics, a relation between SVI and Q7,10m was determined 

and used to estimate SVI at 41 LFPR sites (table 1-1) where 

Q7,10 previously had been estimated by Straub (2001) in 

order to expand the SVI dataset. Only data from LFPR sites 

with highly correlated LFPR-LTCR streamflow-measurement 

pairings (Pearson’s r greater than 0.95) were used to help 

ensure high-quality SVI estimates. The following polynomial 

equation relating Q7,10m to SVI was determined by use of 

ordinary least-square regression using data from 62 LTCR 

sites in Ohio (table 1) with non-zero Q7,10 flows:

SVI X X X = − − − − 10 1 049 0 857 0 287 0 034 2 3 . . . . (2)

where 

X Q = log ( 10 7 1, 0 ) m . 

Equation 2, which has an adjusted Pearson’s correlation coefficient (R2

) of 0.93, is plotted as the curve in figure 1, along 

with the observed values used to develop the equation.

The spatial distribution of SVIs for the 121 LTCR and 41 

LFPR sites used to create the SVI grid is shown in figure 2. 

Spatial gaps in the data are owing to either a lack of available or suitable streamgage data or areas where low flows are 

significantly regulated (and thus SVIs for streamgages in those 

areas are not representative of natural flows). The statewide 

spatial variation in estimated SVI (as represented in the SVI

grid) is illustrated in figure 3.
8 Methods for Estimating Selected Low-Flow Statistics and Development of Annual Flow-Duration Statistics for Ohio

Errors Associated with Estimating SVI at 

Ungaged Sites

A leave-one-out cross-validation technique was used to 

assess the nature of potential errors in SVI when using the grid 

to estimate SVI at ungaged locations. Leave-one-out crossvalidation was done by (1) omitting the SVI observation for 

a single streamgage, (2) using the IDW interpolation method 

to develop a new SVI grid based on the remaining streamgage 

data, (3) determining the new SVI grid value at the omitted 

streamgage location, and (4) computing the residual, which 

is the difference between the SVI value determined from the 

original grid (typically about equal to the SVI value observed 

for the streamgage) and the SVI value determined in step 3. 

These 4 steps were repeated for each of the 162 streamgages 

whose data were used to create the original SVI grid, resulting in a set of 162 residuals. The residuals ranged from −0.51 

to 0.63 with a mean and standard deviation of 0.01 and 0.16, 

respectively. Fifty percent of the residuals were in the range 

of −0.08 to 0.06 equating to estimate errors ranging from 

about −15.4 to 8.5 percent of the observed at-site SVI values 

(figure 4). 

Equations for Estimating Low-Flow Yield 

Statistics as a Function of SVI

The relations between SVI and low-flow yields were 

determined by use of ordinary least-squares regression based 

on data collected through water year 1997 from 79 LTCR sites 

in Ohio (table 2). LFPR and LTCR sites in other States, sites 

with any known regulation (even if considered minor), and 

sites with less well defined SVIs were not used in developing 

the low-flow yield equations. 

Weighted least-squares (WLS) regression is sometimes 

used to develop low-flow equations (Martin and Arihood, 

2010; Wright and Ensminger, 2004); however, we chose 

not to use WLS regression because (a) there is considerable 

uncertainty about how best to weight low-flow estimates, 

Figure 3. Generalized map 

of Ohio showing estimated 

spatial variation in streamflowvariability index.
Methods for Estimating Low-Flow Statistics 9

(b) common weighting schemes that give more weight to 

observations determined from longer record lengths also 

will have the side effect of weighting the regressions toward 

characteristics associated with larger basins,4 and (c) examination of the relation between the standard deviation of the logs 

of annual 7-day low flows versus the years of record for LTCR 

sites in Ohio indicated that although the standard deviation 

appeared to decrease somewhat with longer record length (as 

indicated by the downward-sloping regression line in figure 5, 

the decrease was not statistically significant (the slope of the 

regression line was not significantly different than 0) and 

record length explained only about 2 percent of the variation 

in standard deviation. 

The relations between SVI and the low-flow yields (in 

cubic feet per second per square mile (ft3/s)/mi2) were not 

linear (for example, see fig. 6). Consequently, options for 

developing equations to estimate low-flow yields as a function 

of SVI involve either transformations of the model variables to 

fit a linear equation or fitting data to a non-linear or curvilinear 

equation. While logarithmic and square root transformations 

did a reasonable job of linearizing the relations for data pairs 

4

Because of their importance as water supplies and (or) flooding sources, 

streamgages in Ohio with large drainage areas also tend to have relatively 

long periods of record as compared to streamgages on smaller drainages.

Figure 4. Boxplot showing streamflow-variability index residuals 

from the leave-one-out cross-validation analysis.

Table 2. Equations for estimating selected low-flow yield statistics for Ohio.

[R2, Pearson’s correlation coefficient; all statistics are in units of cubic feet per second per square mile; Q1,10m, 1-day, 10-year low-flow yield; Q7,10m, 

7-day, 10-year low-flow yield; Q30,10m, 30-day, 10-year low-flow yield; Q90,10m, 90-day, 10-year low-flow yield; D80m, 80-percent duration streamflow 

yield; R, low-flow region, use 0 for region A and 1 for region B; SVI, streamflow-variability index in units of base-10 logarithms of cubic feet per second; 

absolute percent errors do not reflect application of the logistic equations]

Equation 

number Equation

Average 

absolute 

percent error 

(APE)

Adjusted 

R2

1

2 3 4

Q1 1, 0m = 0.795 − 3 740 . SVI + 6 633 . SVI − 5 234 . SVI + 1 543 . SVI ; if SVI ≤ 0.80

38.7 0.93

Q1 1, 0m = 0.0 ; if SVI >0.80

2 3 4

Q7 1, 0m = 0.806 − 3 687 . SVI + 6 384 . SVI − 4 938 . SVI + 1 433 . SVI ; if SVI ≤ 0.80

2 Q7 1, 0m = 0.0 ; if SVI >0.80 42.0 .94

2 3 4

Q30 10 , m = 0 783 . − 3 245 . SVI + 5 073 . SVI − 3 535 . SVI + 0 924 . SVI ; if SVI ≤ 0.91

3 Q30 10 , m = 0 0. ; if SVI >0.91 34.2 .95

2 3 4

Q90 10 , m = 0 911 . − 3 868 . SVI + 6 488 . SVI − 5 041 . SVI + 1 504 . SVI +0.013R; if SVI ≤ 1 0.

4 27.2 .94

Q90 10 , m = 0 0. ; if SVI >1.0

5 (0.221 4.715 − SVI +0.350R)

D m 80 = e 15.8 .97
10 Methods for Estimating Selected Low-Flow Statistics and Development of Annual Flow-Duration Statistics for Ohio

Figure 5. Graph showing 

plot of the standard deviation 

of logarithms of annual 7-day, 

10-year low-flow values 

as a function of years of 

streamgage record. 

Figure 6. Graph showing plot 

of 7-day, 10-year low-flow yield 

as a function of streamflowvariability index, illustrating fit 

of the constrained polynomial 

equation.
Methods for Estimating Low-Flow Statistics 11

that did not contain zero-valued flow statistics, the logarithm 

of zero is undefined so data pairs with zero-valued statistics 

had to be omitted or a constant had to be added to the statistics for a logarithmic transformation to be used. Zeros are not 

a problem mathematically when using a square-root transformation; however, they can (and in this case did) produce 

undesirable effects on the regression owing to having a fairly 

wide range of SVI values associated with zero-valued yields. 

Ultimately, it was decided that a polynomial model was the 

best model for most of the low-flow yield statistics because 

it permits all data pairs to be used without modification. 

For most low-flow yield statistics, a 4th degree polynomial 

equation was fit; however, for D80m (the 80-percent duration 

yield), a logarithmic equation was fit because all of the D80m

values in the calibration dataset were nonzero. 

Residuals from all regression analyses were examined 

for normality and homoscedasticity (uniform variance around 

the regression line), and to assess spatial bias. The residuals 

for the statistics showed some indication of heteroscedasticity (fig. 1–1), in these cases indicating that estimate variance 

tended to increase somewhat with increasing predicted yields. 

Shapiro-Wilk tests (Shapiro and Wilk, 1965) indicated that, 

with the exception of D80m, the residuals for the low-flow 

statistics also deviated from normal at an alpha level of 0.05, 

but normal quantile plots (not shown) indicated that they were 

only moderately aberrant in that respect. Several linearizing 

transformations (such as log and square root) were reexamined 

because of these issues; however, residuals from those models 

showed similar or worse indications of heteroscedasticity 

than the original model, so the original form of equation was 

selected. The regression analysis was repeated for the model 

forms shown in table 2 using an option to estimate the asymptotic covariance matrix of the estimates under the hypothesis 

of heteroscedasticity. Using that option results in the same 

parameter estimates as the ordinary least-squares regression 

but provides more robust estimates of their standard errors. 

Using robust standard errors did not change any of the conclusions from the original ordinary least-squares regression. It is 

worth noting that the regression models are valid for prediction in spite of the issues with heteroscedasticity and normality 

of the residuals; however, the variance of the prediction cannot 

be accurately determined. 

The initial regression equations developed for Q90,10m

and D80m had residuals that exhibited noticeable spatial 

bias (no appreciable spatial bias was evident for the other 

statistics); consequently, the State was ultimately broken up 

into two low-flow regions (A and B, fig. 7), and an indicator 

variable (R), set to equal 0 for region A and set to equal 1 for 

region B, was added to the regressions for these two statistics 

to account and correct for the observed bias. The regions were 

divided along 8-digit hydrologic unit code (HUC) boundaries. A variety of spatial datasets (for example, physiographic 

provinces, boundaries of glaciations, and maps of glacial-drift 

thickness) were examined in an attempt to help explain and 

locate appropriate boundaries for the observed regional trends 

in residuals. Ultimately, the transition in residual pattern from 

predominately positive residuals to predominately negative 

residuals appeared to most closely align with boundaries 

between areas of relatively high glacial-drift thickness and 

areas of relatively low or no glacial-drift thickness as defined 

by the Ohio Division of Geological Survey (2004). 

The low-flow yield estimation equations were checked 

to ensure that estimated yields either decreased monotonically or were constant with increasing SVI over the range of 

anticipated SVI values for Ohio. This was found to be true 

except at relatively high SVI values for the polynomial equations. Examination of observed low-flow yields for Q1,10

through Q30,10 at LTCR sites showed that yields typically 

were zero when SVI values exceeded thresholds ranging from 

about 0.8 to 1.0, depending on the statistic being examined. 

Consequently, a constraint was applied to the yield equations 

that forced yields to be zero when those SVI thresholds were 

exceeded. This resulted in low-flow yield estimates that were 

monotonically decreasing or constant (when yields reached 

zero) with increasing SVI. The yield curves also were examined to ensure that the progression of yield estimates for the 

1-, 7-, 30-, and 90-day low flows at a given SVI was logical 

with respect to the statistics and durations being considered 

(for example, the yield for a given duration was always less 

than or equal to the yield for a longer duration for a particular 

SVI level). 

The predictive equations are summarized in table 2, 

and the underlying data used to develop those equations are 

listed in table 1. Values of SVI and streamflow yields reported 

in table 2–1 are based on the low-flow statistics and periods of record listed for those streamgages in Straub (2001). 

The equations in table 2 are based on observations with SVI

magnitudes ranging from about 0.24 to 1.12 log10 (cubic feet 

per second (ft3/s)) for streamgages ranging in drainage area 

from approximately 0.97 to 1,250 square miles (mi2). Figure 6, 

which shows a scatter plot of observed SVI and Q7,10m along 

with a curve representing the corresponding constrained 

polynomial equation (table 1, equation 2), is typical of the fit 

associated with the constrained polynomial equations. The 

equations shown in table 2 were used to estimate low-flow 

yields for each cell in the SVI grid discussed earlier, resulting in grids of low-flow yield estimates whose values can be 

multiplied by drainage area to estimate low-flow statistics (in 

ft3

/s) at ungaged sites. 

Model Error for Low-Flow-Yield Statistic 

Estimation Equations

The low-flow yield grids were used to estimate low-flow 

yields at sites used for model calibration in order to assess the 

relation between observed and predicted values. Low-flow 

yields for the LTCR sites were estimated by determining the 

value corresponding to the low-flow yield grid cell at the location of the site. The low-flow yield estimates were used along 
12 Methods for Estimating Selected Low-Flow Statistics and Development of Annual Flow-Duration Statistics for Ohio

with the observed values to compute a measure of model error 

called the average absolute percent error ( APE ). The APE , 

which is reported in table 2, was determined as 

APE

n

Y Y

Y

i i

i i

n

= −

=

∑

1 100

1

*

( ) 

(3)

where 

Yi and 



Yi are the ith observed and predicted low-flow 

yields, and 

n is the number of observations. 

When computing the APEs, two allowances were made. First, 

if the observed and predicted flows were both zero, the percent 

error for that pair was said to be zero. Second, if the predicted 

flow was nonzero and the observed flow was zero, the percent 

error was undefined and therefore not used in the computation of the APE. APEs ranged from a high of 42.0 percent 

for Q7,10m to a low of 15.8 percent for D80m. It should be 

remembered that model error is not the only source of error for 

the low-flow yield estimate. There also will be error associated 

with the estimate of SVI.

Logistic-Regression Equations for Identification 

of Zero-Valued Low-Flow Statistics

Although the polynomial equations, coupled with the SVI

threshold constraint, produce zero-valued statistic estimates 

for sites with high SVI values, there remained some sites 

(11 for Q1,10m, 8 for Q7,10m, 4 for Q30,10m, and 3 for 

Q90,10m) in the calibration dataset with SVI values lower 

than the thresholds that also had zero-valued statistics. In an 

attempt to improve identification of zero-valued statistics, 

logistic-regression equations (table 3) were developed to estimate the annual probability that the N-day, 10-year low flow is 

zero. Explanatory variables in the logistic-regression equations 

include the SVI and the drainage area (A). The results of the 

equations should be compared to the corresponding annualnonexceedance probability (in this case 0.10) because the 

logistic-regression equations were all developed for statistics 

Figure 7. Map showing lowflow regions used in regression 

equations for Q90,10m, and 

D80m.
Methods for Estimating Low-Flow Statistics 13

with 10-year recurrence intervals. All zero-valued statistics 

in the calibration dataset occurred in association with SVI

values greater than 0.50; therefore, at a minimum, the logisticregression equations should be used whenever a site has an 

estimated SVI greater than 0.50 and a non-zero statistic is 

computed for the statistics listed in table 3. It is recommended 

that the estimate for the statistic be revised to zero if the computed probability is greater than or equal to 0.10. 

Logistic-regression equations were developed for 

the Q1,10, Q7,10, and Q30,10 statistics (table 3). Table 3 

includes information about equation specificity (the percentage of non-zero statistics correctly identified), equation 

sensitivity (the percentage of zero-valued statistics correctly 

identified), and the overall percentage of correct classifications when classifying based on an annual-nonexceedance 

probability of 0.10. No logistic-regression equations were 

developed for the Q90,10 and D80 statistics because there 

were either too few zero-valued statistics in the calibration 

dataset with which to develop reliable logistic equations (in 

the case of Q90,10) or there were no zero-valued statistics 

(in the case of D80) .

The low-flow yield equations (table 2) and logisticregression equations (table 3) have been incorporated into 

the StreamStats application for Ohio, which can accessed at 

http://water.usgs.gov/osw/streamstats/ohio.html. The StreamStats application for Ohio will automatically compute the 

drainage areas and low-flow statistics listed in table 2 using 

the same site-selection procedures used for other Ohio streamflow statistics, as described by Koltun and others (2006). 

StreamStats will convert the computed yields to streamflows, 

in units of cubic feet per second, by taking the product of the 

drainage area and yields.

Limitations of the Estimating Equations

The regression models are applicable to unregulated 

streams in Ohio that are not appreciably affected by local 

diversions or other forms of streamflow regulation. Large 

springs and sinks common to karst terrain in areas underlain 

by limestone can appreciably affect low flows. The regression models do not directly account for karst terrain, so model 

results can be erroneous when applied to basins with karst 

areas. The StreamStats application for Ohio makes no determination of streamflow regulation and provides no information 

on the presence of karst terrain; consequently, it is the user’s 

responsibility to determine where and when the regression 

models can be suitably applied.

The estimating equations were developed by regressing 

streamflow statistics on explanatory variables. The SVI was an 

explicit explanatory variable in the regression, and drainage 

area was an implicit explanatory variable in that it was used 

to compute the low-flow yields. SVI values for stations used 

in the regression analysis ranged from about 0.24 to 1.12 log10

(ft3/s), and drainage areas ranged from about 1 to 1,250 mi2

(table 1). The applicability of the regression equations is 

unknown when applied to basins with characteristics outside 

these ranges. 

The SVI appeared to be much more strongly related to the 

low-flow statistics than the more traditional basin characteristics that were tested; however, there are some drawbacks to 

using SVI as an explanatory variable. Unlike many traditional 

basin characteristics, SVI is not a physical feature of a basin 

but instead reflects a variety of hydrologic processes integrated 

over an area draining to the point of interest. Consequently, 

SVI could not be determined from readily available spatial 

datasets, so a new spatial dataset for SVI, consisting of a grid 

Table 3. Logistic-regression equations for estimating the annual probability of zero flow for selected 

low-flow statistics for unregulated streams in Ohio.

[A, drainage area, in square miles; p, probability that the N-day, 10-year low flow does not exceed zero; Q1,10, 1-day, 10‐year 

low flow; Q7,10, 7-day, 10-year low flow; Q30,10, 30-day, 10-year low flow; SVI, streamflow-variability index; specificity, 

percentage of non-zero statistics correctly identified; sensitivity, percentage of zero-valued statistics correctly identified]

Statistic Equation

Percent 

correct 

at p=0.10

Specificity 

at p= 0.10 

(percent)

Sensitivity

at p=0.10 

(percent)

Q1,10

3

3

( 8.680 9.576 5.650 10 )

( 8.680 9.576 5.650 10 ) (1 )

SVI x A

SVI x A

e

p

e

−

−

−+ −

−+ − = +

90.6 91.5 74.7

Q7,10

3

3

( 9.973 10.35 5.020 10 )

( 9.973 10.35 5.020 10 ) (1 )

SVI x A

SVI x A

e

p

e

−

−

−+ −

−+ − = +

93.7 94.6 73.6

Q30,10

( 14.26 12.35 )

( 14.26 12.35 ) (1 )

SVI

SVI

e

p

e

− +

− + = +

97.2 97.5 69.0
14 Methods for Estimating Selected Low-Flow Statistics and Development of Annual Flow-Duration Statistics for Ohio

composed of 1 km2 grid cells, was constructed to facilitate 

its estimation throughout the State. Although every effort 

was made to produce the best possible SVI spatial dataset, 

it must be remembered that SVI is being estimated and so is 

subject to error. Those errors will be reflected in the low-flow 

yield estimates computed by StreamStats. Operation of a 

LTCR or LFPR streamgage at a site should be considered to 

provide a streamflow-based estimate of SVI for applications 

where uncertainties in the low-flow estimates will be poorly 

tolerated.

Methods for Annual Flow-Duration 

Analyses

Instead of using the traditional class-interval-based 

approach for defining FDCs described by Searcy (1959), 

a more direct and efficient quantile-estimation procedure, 

as recommend by Vogel and Fennessey (1994), was used 

to the compute annual flow-duration statistics discussed in 

this report. A program was written in the Statistical Analysis 

System (SAS) programming language (Version 9.1, SAS 

Institute Inc.) that computed and output selected quantiles of 

daily and 7-day-average streamflows for annual and seasonal 

periods for each climatic year in the station record that was 

complete (that is, it had no missing record). The season examined in this study is the period September–November, which, 

in Ohio, frequently contains the lowest streamflows during the 

year. The quantiles that were computed and output for each 

climatic year include the 99-, 98-, 95-, 90-, 80-, 75-, 70-, 60-, 

50-, 40-, 30-, 25-, 20-, 10-, 5-, 2-, and 1-percent exceedance 

streamflows [defined as 100P{Q>qp} , where Q represents the 

daily mean (or 7-day average) streamflows during the climatic 

year or season, and qp is the value of the daily mean (or 7-day 

average) streamflow that equaled or exceeded P percent of the 

time in the climatic year or season]. The qp values that were 

equaled or exceeded n percent of the time over the analytical 

period are presented in data tables in appendixes 2–4 with n 

shown in the first column labeled APEE (annual percentage 

equaled or exceeded). 

The flow-duration quantiles were computed from the 

observed Q time series by ranking the observed streamflows 

[q(i), i=1,...,n where n = the number of days (or averaging 

periods) in the climatic year or season] and computing the 

quantiles (exceedance percentiles) using the type 4 quantileestimator option of the SAS UNIVARIATE procedure (SAS 

Institute Inc., 2011). The SAS type 4 quantile estimator is an 

L-moment-type estimator that provides weighted averages 

of adjacent order statistics (Vogel and Fennessey, 1994). The 

quantile estimator is defined as

q q i q i p = − ( ) 1 1   ( ) + + ( ) (4)

where 

 equals the fractional portion of (n+1)p/100 

and 

i equals the integer portion of (n+1)p/100 and 

where

q n( ) +1 is taken to be q(n ).

To permit assessment of whether a single theoretical distribution could be used to describe the distribution of annual 

qp series (that is, qp(i), i=1,..., m, where m = the number of 

complete years of record), the SAS program was designed to 

plot ordered values of the observed distribution of annual qp 

values versus percentiles of selected theoretical distributions. 

The distributions plotted included the lognormal, Weibull, 

and gamma (also called Pearson Type III) distributions. These 

distributions were chosen, in part, based on recommendations made by Kroll and Vogel (2002). Ultimately, many of 

the annual qp series appeared to be reasonably well fit by one 

or more of the three distributions (with Weibull and gamma 

distributions providing good fit to many of the annual qp 

series); however, none of the distributions fit the annual series 

well for all annual-exceedance probabilities at all of the LTCR 

sites (including some unregulated sites with long periods (>50 

years) of record. In particular, few of the high-percent exceedance-level series (such as the 95- or 98-percent exceeds series) 

were well fit.

A second program, written in the MATLAB programming language (The MathWorks Inc., 2010), was used to take 

the annual qp values determined with the SAS program and 

compute quantiles of those estimates. For example, assume 

a streamflow-gaging station had 30 complete climatic years 

of record. The SAS program would compute qp estimates for 

selected exceedance percentiles for each of the 30 years. The 

MATLAB program would then order the annual qp values 

and compute quantiles of the 30-year qp series. Quantiles of 

the annual qp series are represented by the symbol qp,k; where 

k is the percentage of time over the n years of record that the 

annual qp value was exceeded (for example, q50,90 is the annual 

50th percentile streamflow that was equaled or exceeded 90 

percent of the time over the 30-year period). Initially, it was 

hoped that the qp,k estimates could be determined by fitting 

a theoretical distribution to the annual qp series; however, 

because the annual qp series for some annual-exceedance 

probabilities were poorly fit by the theoretical distributions 

for some LTCR streamflow-gaging stations, that approach 

was rejected in favor of estimating qp,k using the same quantile 

estimator (equation 4) used when analyzing the individual 

climatic-year series. 

One of two predetermined sets of exceedance percentiles of the annual qp

 values were computed depending on the 

number of climatic years of record analyzed. If there were 50 

or more years of record, the following exceedance percentiles 

were computed: 2, 5, 10, 20, 50, 80, 90, 95, and 98 percent. 

If there were less than 50 years of record, but greater than or 

equal to 20 years of record, exceedance percentiles of 5, 10, 
Methods for Annual Flow-Duration Analyses 15

20, 30, 50, 70, 80, 90, and 95 percent were computed (streamflow-gaging stations with less than 20 complete climatic 

years of record were not used). These two sets of exceedance percentiles were chosen so as to maximize the range of 

exceedance percentiles computed for a given record length 

yet still base all calculations on interpolations from computed 

quantiles.

The process used to compute the qp,k values is illustrated 

in figure 8 using data from the streamflow-gaging station on 

Wheeling Creek below Blaine, Ohio (station 03111548). The 

black lines in the lower plot of figure 8 represent the annualexceedance plots for each complete climatic year from 1983 

through 2008. If one examines the magnitudes of streamflows 

corresponding to the annual 50-percent exceedance value 

(those lying along the red line in the lower plot), one can see 

that they range from 38 to 152 ft3/s. The computed exceedance 

percentiles for the annual values lying along that line (that is 

the q50,k values) are plotted as the red line in the upper left-hand 

plot and are tabulated in the row corresponding to an APEE 

value of 50 in appendix 3 (top table on page 381). If instead 

one examines the magnitudes of streamflows corresponding 

to the annual 90-percent exceedance value (those lying along 

the blue line in the lower plot), one can see that the computed 

exceedance percentiles range from 14 to about 70.2 ft3/s. The 

computed exceedance percentiles for the annual 90-percent 

exceedance streamflows (that is the q90,k values) are plotted as 

the blue line in the upper right-hand plot and are tabulated in 

the row corresponding to an APEE value of 90 in appendix 3 

(top table on page 38). If the top two plots were combined into 

one plot, one would observe that the blue line would lie below 

the red line, which is consistent with the expectation that the 

90-percent exceedance streamflows should be less than or 

equal to the 50-percent exceedance streamflows.

Figure 8. Graphs illustrating the process used to compute selected quantiles of the annual qp series.
16 Methods for Estimating Selected Low-Flow Statistics and Development of Annual Flow-Duration Statistics for Ohio

Results and Discussion of Annual 

Flow-Duration Analyses

Results of the annual and annual seasonal-period 

flow-duration analyses are presented in appendixes 3–6. 

Appendixes 3 and 4 contain results from the annual and annual 

seasonal-period analyses, respectively, for 67 to 70 LTCR 

sites5 that have no or minimal regulation, whereas appendixes 

5 and 6 contain results from the annual and annual seasonalperiod analyses, respectively, for 40 LTCR sites with streamflows that are subject to appreciable regulation. Maps showing 

the location of flow-duration sites that were thought to have no 

or minimal streamflow regulation and flow-duration sites that 

have streamflows that are subject to appreciable regulation are 

shown in figures 9 and 10, respectively.

The annual flow-duration characteristics presented in this 

report offer some advantages over traditional flow-duration 

characteristics. For example, one could construct a flowduration curve composed of medians of the annual-exceedance 

percentiles (that is q50,k values) to represent the distribution 

of daily streamflows in a median hypothetical year. Although 

the likelihood of actually observing such a year in nature is 

small (because all of the flow percentiles for the year would 

have to have a common annual-exceedance probability), the 

data support such analyses. Also, if a design calls for use of a 

specific annual-flow duration, one can consider the annual risk 

of exceedance or nonexceedance of that flow-duration value. 

Although risk-based assessments are possible, one should be 

particularly cautious of such interpretations for streams that 

are subject to regulation given that future changes in regulation could alter the flow-duration characteristics. 

The following is an example of how the flow-duration 

data presented in this report might be used. For example, a 

5

 Three sites had sufficient record to do annual seasonal-period analyses but 

did not have sufficient record to do annual analyses.

side-channel reservoir is being designed for a location adjacent 

to Wheeling Creek below Blaine, Ohio (station 03111548), 

and there is a flow-by requirement6 equal to the annual 

80-percent duration streamflow or the total streamflow, whichever is smaller. The amount of water that is required to flow by 

the reservoir can affect how rapidly the reservoir can be filled 

(since the flow-by requirement reduces the amount available 

for withdrawal); however, too small of a flow-by requirement 

may negatively impact downstream water quality and the 

health of aquatic biota. 

If we examine the column corresponding to the annual 

80-percent duration streamflow (that is, the daily mean 

streamflow that is equaled or exceeded 80 percent of the 

time in a given year) for Wheeling Creek below Blaine, Ohio 

(appendix 3, top table on page 38), we see that 50 percent of 

the time (row corresponding to APEE = 50) the streamflow 

magnitude equaled or exceeded 52 ft3/s. That means that in 

about one-half of the years, the annual 80-percent duration 

streamflow was greater than 52 ft3/s. Should we wish to be 

more protective of the stream by assuring that the annual 

80-percent duration streamflow that occurs in most years is 

allowed to pass by the reservoir, then we may wish to use 

an annual 80-percent duration streamflow that has a smaller 

annual-exceedance probability. For example, we could choose 

an annual 80-percent duration streamflow that was exceeded 

in only 10 percent of the years (row corresponding to APEE 

= 10), which would increase the flow-by requirement to 

166 ft3/s. Although increasing the flow-by requirement may 

provide greater downstream protection, it also may necessitate 

increasing the pump capacity and (or) volume of the reservoir 

so that there is sufficient water to meet demand at all times.

6

 A flow-by requirement is the minimum quantity of streamflow that must 

be allowed to flow by a point on a stream. Flow-by requirements typically are 

established to help ensure that there is sufficient streamflow downstream from 

an impoundment or withdrawal point on a stream to support ecological or 

water-use demands, or to supply other legally mandated minimum in-stream 

flows.
Results and Discussion of Annual Flow-Duration Analyses 17

Figure 9. Map showing locations of streamflow-gaging stations with annual flow-duration analyses that have no or minimal 

streamflow regulation.
18 Methods for Estimating Selected Low-Flow Statistics and Development of Annual Flow-Duration Statistics for Ohio

Figure 10. Map showing locations of streamflow-gaging stations with annual flow-duration analyses that have streamflows that are 

subject to appreciable regulation.
References Cited 19

Summary

Streamflow statistics are used for a variety of purposes. 

Among other uses, both low-flow and flow-duration statistics 

are particularly useful for making decisions about the suitability of a stream to act as an industrial or public water supply 

or as a suitable destination for waste effluents. In spite of the 

widespread need for such statistics, precomputed statistics are 

available for only a small number of locations in Ohio. Consequently, it is important that streamflow statistics be determined 

for suitable gaged locations, and it is highly desirable that 

methods be developed to permit estimation of those statistics 

at ungaged locations.

Ordinary least-squares 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 (SVI), are based on lowflow statistics published by Straub (2001) for 79 long-term 

continuous record streamgages with data collected through 

water year 1997. Constraints were applied to the equations 

to ensure that zero-valued yields were computed when SVI

magnitudes exceeded thresholds above which all low-flow 

yields for a given statistic were observed to be zero in the 

calibration dataset. The average absolute percent error for the 

constrained regression equations, when applied to the calibration dataset, ranged from 15.8 to 42.0 percent. The regression 

results have been incorporated into the U.S. Geological Survey 

StreamStats application for Ohio in the form of a yield grid to 

facilitate estimation of the corresponding streamflow statistics 

in cubic feet per second. Although the constrained polynomial regression equations presented in this report can produce 

zero-valued estimates, logistic-regression equations also were 

developed for selected low-flow statistics to help identify 

occurrences of zero-valued statistics.

Traditional flow-duration curves (FDCs) show the 

percentage of time that daily mean streamflow of a given 

magnitude was equaled or exceeded over a long period of 

time. While these traditional FDCs provide useful information 

about long-term streamflow-exceedance characteristics, their 

utility is diminished when trying to answer questions about 

exceedance characteristics within a typical year. To address the 

need for stochastically relevant annual flow-duration 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 annualexceedance percentiles were computed and are tabulated in 

this report to help facilitate consideration of the annual risk of 

exceedance or nonexceedance of annual and annual seasonalperiod flow-duration values. 

References Cited

Environmental Systems Research Institute, 2008, ArcGIS 

Desktop 9.3 Help—How inverse distance weighted 

(IDW) interpolation works, accessed May 21, 2012, 

at http://webhelp.esri.com/arcgiSDEsktop/9.3/index.

cfm?TopicName=How_Inverse_Distance_Weighted_

(IDW)_interpolation_works. 

Koltun, G.F., Kula, S.P., and Puskas, B.M., 2006, A streamflow statistics (StreamStats) Web application for Ohio: 

U.S. Geological Survey Scientific Investigations Report 

2006–5312, 62 p.

Koltun, G.F., and Schwartz, R.R., 1987, Multiple-regression 

equations for estimating low flows at ungaged stream 

sites in Ohio: U.S. Geological Survey Water-Resources 

Investigations Report 86–4354, 39 p. 

Koltun, G.F., and Whitehead, M.T., 2002, Techniques for estimating selected streamflow characteristics of rural unregulated streams in Ohio: U.S. Geological Survey WaterResources Investigations Report 2002–4068, 50 p.

Kroll, C.N., and Vogel, R.M., 2002, Probability distribution 

of low streamflow series in the United States: American Society of Civil Engineers, Journal of Hydrologic 

Engineering, v. 7, no. 2, p. 137–146.

Martin, G.R., and Arihood, L.D., 2010, Methods for estimating selected low-flow frequency statistics for unregulated 

streams in Kentucky: U.S. Geological Survey Scientific 

Investigations Report 2010–5217, 83 p., plus 2 pl.

Ohio Division of Geological Survey, 2004, Shaded drift-thickness map of Ohio: Ohio Department of Natural Resources, 

Division of Geological Survey Map SG-3, generalized 

page-size version with text, 3 p., scale 1:2,000,000.

SAS Institute, Inc., 2011, The UNIVARIATE Procedure—Calculating percentiles, accessed May 15, 

2010, at http://support.sas.com/documentation/cdl/en/

procstat/63104/HTML/default/viewer.htm#procstat_

univariate_sect028.htm. 

Searcy, J.K., 1959, Manual of hydrology—Part 2, Low flow 

techniques—Flow-duration curves: U.S. Geological Survey 

Water-Supply Paper, 1542-A, 33 p.

Shapiro, S.S., and Wilk, M.B., 1965, An analysis of variance 

test for normality (complete samples): Biometrika, v. 52, 

no. 3/4, p. 591–611.
Straub, D.E., 2001, Low-flow characteristics of streams in 

Ohio through water year 1997: U.S. Geological Survey 

Water-Resources Investigations Report 2001–4140, 415 p.

Sugiyama, Hironobu, Vudhivanich, Varawoot, Whitaker, A.C., 

and Lorsirirat, Kosit, 2003, Stochastic flow duration curves 

for evaluation of flow regimes in rivers: Journal of the American Water Resources Association, v. 39, no. 1, p. 47–58.

The MathWorks, Inc., 2010, MATLAB ver. 7.11 (R2010b)—

Data Analysis: Natick, Mass., The MathWorks, Inc. 

[variously paginated], accessed May 5, 2012, at 

http://www.mathworks.com/help/releases/R2010b/pdf_doc/

matlab/data_analysis.pdf. 

Vogel, R.M., and Fennessey, N.M., 1994, Flow-duration 

curves—I, New interpretation and confidence intervals: 

American Society of Civil Engineers, Journal of Water 

Resources Planning and Management, v. 120, no. 4, 

p. 485–504.

Wright, L.S., and Ensminger, P.A., 2004, Regionalized regression equations for estimating low-flow characteristics for 

selected Louisiana streams: Louisiana Department of Transportation and Development Water Resources Technical 

Report No. 75, 33 p.
Appendix 1 21

Appendix 1. Miscellaneous Supporting Data

Table 1-1. Streamflow-variability index (SVI) values for locations in Ohio and adjacent States used for SVI-related analyses.

[Streamflow-variability index, in units of base-10 logarithms of cubic feet per second; LTCR, long-term continuous record; LFPR, low-flow partial record]

Station number Station name Decimal 

latitude

Decimal 

longitude

Streamflowvariability 

index

Site type

03089500 Mill Creek near Berlin Center, Ohio 41.000 -80.968 0.688 LTCR

03092000 Kale Creek near Pricetown, Ohio 41.140 -80.995 0.808 LTCR

03092090 West Branch Mahoning River near Ravenna, Ohio 41.161 -81.197 0.507 LTCR

03093000 Eagle Creek at Phalanx Station, Ohio 41.261 -80.954 0.449 LTCR

03094500 Mahoning River at Warren, Ohio 41.244 -80.827 0.478 LTCR

03102000 Shenango River near Jamestown Pennsylvania 41.458 -80.425 0.492 LTCR

03102500 Little Shenango River at Greenville Pennsylvania 41.422 -80.376 0.673 LTCR

03102950 Pymatuning Creek at Kinsman, Ohio 41.443 -80.588 0.627 LTCR

03108980 Middle Fork Little Beaver Creek near Salem, Ohio 40.906 -80.805 0.379 LFPR

03108985 Cherry Valley Run at Leetonia, Ohio 40.876 -80.756 0.448 LFPR

03108996 Middle Fork Little Beaver Creek at Teegarden, Ohio 40.822 -80.827 0.439 LFPR

03109000 Lisbon Creek at Lisbon, Ohio 40.782 -80.765 0.621 LTCR

03109395 Bull Creek at Negley, Ohio 40.788 -80.545 0.484 LFPR

03109400 North Fork Little Beaver Creek near Negley, Ohio 40.775 -80.543 0.434 LFPR

03109500 Little Beaver Creek near East Liverpool, Ohio 40.676 -80.541 0.481 LTCR

03110000 Yellow Creek near Hammondsville, Ohio 40.538 -80.725 0.544 LTCR

03111465 Short Creek at Adena, Ohio 40.219 -80.873 0.395 LFPR

03111500 Short Creek near Dillonvale, Ohio 40.193 -80.734 0.380 LTCR

03111548 Wheeling Creek below Blaine, Ohio 40.067 -80.808 0.328 LTCR

03112000 Wheeling Creek at Elm Grove West Virginia 40.045 -80.661 0.708 LTCR

03114000 Captina Creek at Armstrongs Mills, Ohio 39.909 -80.924 0.680 LTCR

03114500 Middle Island Creek at Little, West Virginia 39.475 -80.997 0.751 LTCR

03115400 Little Muskingum River at Bloomfield, Ohio 39.563 -81.204 0.752 LTCR

03115500 Little Muskingum River at Fay, Ohio 39.480 -81.286 0.783 LTCR

03115650 East Fork Duck Creek at Lower Salem, Ohio 39.574 -81.390 0.669 LFPR

03117310 Pipe Run at Malvern, Ohio 40.688 -81.184 0.679 LFPR

03117500 Sandy Creek at Waynesburg, Ohio 40.673 -81.260 0.440 LTCR

03122900 Sugar Creek near West Lebanon, Ohio 40.737 -81.653 0.609 LFPR

03123000 Sugar Creek above Beach City Dam at Beach City, 

Ohio

40.657 -81.577 0.541 LTCR

03123300 South Fork Sugar Creek near Dundee, Ohio 40.593 -81.614 0.613 LFPR

03125000 Home Creek near New Philadelphia, Ohio 40.468 -81.403 1.037 LTCR

03127100 Crooked Creek near Stillwater, Ohio 40.308 -81.324 0.690 LFPR

03129100 White Eyes Creek near Fresno, Ohio 40.305 -81.750 0.673 LFPR

03130500 Touby Run at Mansfield, Ohio 40.765 -82.545 0.512 LTCR

03134000 Jerome Fork at Jeromeville, Ohio 40.802 -82.200 0.569 LTCR

03134300 Muddy Fork near Rowsburg, Ohio 40.836 -82.138 0.549 LFPR

03136500 Kokosing River at Mount Vernon, Ohio 40.406 -82.500 0.424 LTCR

03137000 Kokosing River at Millwood, Ohio 40.398 -82.286 0.434 LTCR
22 Methods for Estimating Selected Low-Flow Statistics and Development of Annual Flow-Duration Statistics for Ohio

Station number Station name Decimal 

latitude

Decimal 

longitude

Streamflowvariability 

index

Site type

03138790 Killbuck Creek at Burbank, Ohio 40.990 -81.995 0.650 LFPR

03139000 Killbuck Creek at Killbuck, Ohio 40.481 -81.986 0.448 LTCR

03140000 Mill Creek near Coshocton, Ohio 40.363 -81.862 0.640 LTCR

03143760 Wakatomika Creek near Perryton, Ohio 40.220 -82.181 0.511 LFPR

03144000 Wakatomika Creek near Frazeysburg, Ohio 40.133 -82.148 0.522 LTCR

03146000 North Fork Licking River at Utica, Ohio 40.228 -82.452 0.598 LTCR

03146500 Licking River near Newark, Ohio 40.059 -82.340 0.467 LTCR

03149500 Salt Creek near Chandlersville, Ohio 39.909 -81.860 0.655 LTCR

03154500 Reedy Creek near Reedy, West Virginia 38.961 -81.390 0.862 LTCR

03155500 Hughes River at Cisco, West Virginia 39.119 -81.277 0.739 LTCR

03155895 Hocking River at Union St at Lancaster, Ohio 39.718 -82.610 0.415 LFPR

03156000 Hunters Run at Lancaster, Ohio 39.709 -82.622 0.422 LTCR

03156549 Center Branch Rush Creek near Junction City, Ohio 39.723 -82.343 0.632 LFPR

03156550 Rush Creek near Junction City, Ohio 39.720 -82.350 0.552 LFPR

03156900 Clear Creek at Clearport, Ohio 39.618 -82.680 0.667 LFPR

03157000 Clear Creek near Rockbridge, Ohio 39.588 -82.578 0.376 LTCR

03157500 Hocking River at Enterprise, Ohio 39.565 -82.475 0.445 LTCR

03159536 West Branch Shade River at Chester, Ohio 39.100 -81.926 0.689 LFPR

03159538 Middle Branch Shade River at Chester, Ohio 39.104 -81.923 0.704 LFPR

03159540 Shade River near Chester, Ohio 39.064 -81.882 0.687 LTCR

03159555 East Branch Shade River near Tuppers Plains, Ohio 39.141 -81.877 0.753 LFPR

03201600 Sandy Run ab Big Four Hollow Creek near Lake 

Hope, Ohio

39.363 -82.313 0.581 LTCR

03201700 Big Four Hollow Creek near Lake Hope, Ohio 39.363 -82.314 0.623 LTCR

03201800 Sandy Run near Lake Hope, Ohio 39.334 -82.332 1.077 LTCR

03201990 Little Raccoon Creek near Vinton, Ohio 38.953 -82.366 0.616 LFPR

03202000 Raccoon Creek at Adamsville, Ohio 38.876 -82.356 0.655 LTCR

03204000 Guyandotte River at Branchland, West Virginia 38.221 -82.203 0.545 LTCR

03204500 Mud River near Milton, West Virginia 38.388 -82.113 0.820 LTCR

03216500 Little Sandy River at Grayson, Kentucky 38.330 -82.939 0.720 LTCR

03216540 East Fork Little Sandy River near Fallsburg, Kentucky 38.234 -82.709 0.800 LTCR

03217500 Scioto River at Larue, Ohio 40.572 -83.384 0.664 LTCR

03218000 Little Scioto River above Marion, Ohio 40.629 -83.170 1.008 LTCR

03219500 Scioto River near Prospect, Ohio 40.420 -83.197 0.639 LTCR

03219590 Bokes Creek near Warrensburg, Ohio 40.322 -83.175 1.539 LTCR

03219600 Eagon Run near Warrensburg, Ohio 40.328 -83.153 0.914 LTCR

03220000 Mill Creek near Bellepoint, Ohio 40.248 -83.174 0.689 LTCR

03222500 Olentangy River near New Winchester, Ohio 40.747 -82.905 0.670 LFPR

03222700 Mud Run near Caledonia, Ohio 40.689 -82.962 0.671 LFPR

03222800 Flat Run near Caledonia, Ohio 40.631 -82.948 0.715 LFPR

03223000 Olentangy River at Claridon, Ohio 40.583 -82.989 0.681 LTCR

Table 1-1. Streamflow-variability index (SVI) values for locations in Ohio and adjacent States used for SVI-related analyses.—

Continued

[Streamflow-variability index, in units of base-10 logarithms of cubic feet per second; LTCR, long-term continuous record; LFPR, low-flow partial record]
Appendix 1 23

Station number Station name Decimal 

latitude

Decimal 

longitude

Streamflowvariability 

index

Site type

03224000 Shaw Creek at Shawtown, Ohio 40.483 -82.957 0.690 LFPR

03224500 Whetstone Creek near Ashley, Ohio 40.455 -82.958 0.618 LTCR

03230230 Big Darby Creek near West Jefferson, Ohio 39.980 -83.249 0.642 LFPR

03230310 Little Darby Creek at West Jefferson, Ohio 39.951 -83.269 0.651 LFPR

03230400 Big Darby Creek at Darbydale, Ohio 39.850 -83.189 0.630 LFPR

03230500 Big Darby Creek at Darbyville, Ohio 39.701 -83.110 0.583 LTCR

03230600 Hominy Creek at Circleville, Ohio 39.591 -82.924 0.542 LFPR

03230745 Deer Creek at US Route 142 near London, Ohio 39.905 -83.393 0.586 LFPR

03230800 Deer Creek at Mount Sterling, Ohio 39.715 -83.257 0.500 LTCR

03231800 Sugar Creek near Rock Mills, Ohio 39.470 -83.435 0.987 LFPR

03232000 Paint Creek near Greenfield, Ohio 39.379 -83.375 0.742 LTCR

03235000 Salt Creek at Tarlton, Ohio 39.556 -82.781 0.796 LTCR

03235090 Salt Creek at Adelphi, Ohio 39.473 -82.750 0.624 LFPR

03236000 Salt Creek near Londonderry, Ohio 39.256 -82.770 0.600 LTCR

03236800 Salt Creek at Richmond Dale, Ohio 39.200 -82.811 0.630 LFPR

03237280 Upper Twin Creek at McGaw, Ohio 38.644 -83.216 0.921 LTCR

03237500 Ohio Brush Creek near West Union, Ohio 38.804 -83.421 0.788 LTCR

03237900 Cabin Creek near Tollesboro, Kentucky 38.568 -83.537 1.150 LTCR

03238500 White Oak Creek near Georgetown, Ohio 38.858 -83.929 0.818 LTCR

03239000 Little Miami River near Selma, Ohio 39.810 -83.739 0.531 LFPR

03240000 Little Miami River near Oldtown, Ohio 39.748 -83.931 0.409 LTCR

03240500 North Fork Massie Creek at Cedarville, Ohio 39.757 -83.790 0.580 LTCR

03241000 South Fork Massie Creek near Cedarville, Ohio 39.739 -83.764 0.727 LTCR

03241500 Massies Creek at Wilberforce, Ohio 39.723 -83.883 0.514 LTCR

03242050 Little Miami River near Spring Valley, Ohio 39.583 -84.030 0.323 LTCR

03242200 Anderson Fork near New Burlington, Ohio 39.566 -83.903 0.669 LTCR

03246200 East Fork Little Miami River near Marathon, Ohio 39.115 -84.025 0.676 LTCR

03246500 East Fork Little Miami River at Williamsburg, Ohio 39.053 -84.050 0.881 LTCR

03251000 North Fork Licking River near Lewisburg, Kentucky 38.549 -83.794 1.250 LTCR

03254400 North Fork Grassy Creek near Piner, Kentucky 38.792 -84.514 1.350 LTCR

03260700 Bokengehalas Creek near De Graff, Ohio 40.347 -83.891 0.371 LTCR

03260800 Stony Creek near De Graff, Ohio 40.291 -83.910 0.358 LTCR

03265000 Stillwater River at Pleasant Hill, Ohio 40.058 -84.356 0.521 LTCR

03266000 Stillwater River at Englewood, Ohio 39.870 -84.286 0.533 LTCR

03266500 Mad River at Zanesfield, Ohio 40.350 -83.674 0.402 LTCR

03267000 Mad River near Urbana, Ohio 40.108 -83.799 0.253 LTCR

03268000 Buck Creek at New Moorefield, Ohio 39.992 -83.715 0.243 LTCR

03270800 Wolf Creek at Trotwood, Ohio 39.794 -84.310 0.644 LTCR

03271000 Wolf Creek at Dayton, Ohio 39.767 -84.237 0.494 LTCR

03271400 Bear Creek at Ellerton, Ohio 39.673 -84.310 0.545 LFPR

03271736 Twin Creek at Lewisburg, Ohio 39.855 -84.532 0.600 LFPR

Table 1-1. Streamflow-variability index (SVI) values for locations in Ohio and adjacent States used for SVI-related analyses.—

Continued

[Streamflow-variability index, in units of base-10 logarithms of cubic feet per second; LTCR, long-term continuous record; LFPR, low-flow partial record]
24 Methods for Estimating Selected Low-Flow Statistics and Development of Annual Flow-Duration Statistics for Ohio

Station number Station name Decimal 

latitude

Decimal 

longitude

Streamflowvariability 

index

Site type

03271800 Twin Creek near Ingomar, Ohio 39.708 -84.525 0.574 LTCR

03272000 Twin Creek near Germantown, Ohio 39.638 -84.404 0.577 LTCR

03272700 Sevenmile Creek at Camden, Ohio 39.629 -84.644 0.560 LTCR

03272800 Sevenmile Creek at Collinsville, Ohio 39.523 -84.611 0.578 LTCR

03274650 Whitewater River near Economy, Indiana 40.004 -85.116 0.577 LTCR

03274750 Whitewater River near Hagerstown, Indiana 39.874 -85.163 0.332 LTCR

03275000 Whitewater River near Alpine, Indiana 39.579 -85.158 0.397 LTCR

03275600 East Fork Whitewater River at Abington, Indiana 39.733 -84.960 0.397 LTCR

03276700 South Hogan Creek near Dillsboro, Indiana 39.030 -85.038 0.818 LTCR

03291500 Eagle Creek at Glencoe, Kentucky 38.705 -84.824 1.350 LTCR

03325500 Mississinewa River near Ridgeville, Indiana 40.280 -84.992 0.644 LTCR

04096515 South Branch Hog Creek near Allen, Michigan 41.949 -84.828 0.395 LTCR

04175700 River Raisin near Tecumseh, Michigan . 41.944 -83.945 0.316 LTCR

04176000 River Raisin near Adrian, Michigan 41.905 -83.981 0.343 LTCR

04177720 Fish Creek at Hamilton, Indiana 41.532 -84.904 0.500 LTCR

04178000 St. Joseph River near Newville, Indiana 41.385 -84.802 0.518 LTCR

04179500 Cedar Creek at Auburn, Indiana 41.366 -85.052 0.551 LTCR

04180000 Cedar Creek near Cedarville, Indiana 41.219 -85.076 0.447 LTCR

04182810 Spy Run Creek at Fort Wayne, Indiana 41.105 -85.153 0.415 LTCR

04184500 Bean Creek at Powers, Ohio 41.659 -84.249 0.495 LTCR

04185440 Unnamed Tributary to Lost Creek near Farmer, Ohio 41.362 -84.691 0.825 LTCR

04188500 Eagle Creek near Findlay, Ohio 40.993 -83.651 1.123 LTCR

04189500 Blanchard River at Glandorf, Ohio 41.044 -84.082 0.671 LTCR

04196000 Sandusky River near Bucyrus, Ohio 40.804 -83.006 0.632 LTCR

04196500 Sandusky River near Upper Sandusky, Ohio 40.851 -83.256 0.660 LTCR

04197000 Sandusky River near Mexico, Ohio 41.044 -83.195 0.637 LTCR

04197100 Honey Creek at Melmore, Ohio 41.022 -83.110 0.765 LTCR

04197170 Rock Creek at Tiffin, Ohio 41.114 -83.168 0.553 LTCR

04198000 Sandusky River near Fremont, Ohio 41.308 -83.159 0.644 LTCR

04198500 East Branch Huron River near Norwalk, Ohio 41.249 -82.648 0.567 LTCR

04199000 Huron River at Milan, Ohio 41.301 -82.608 0.582 LTCR

04199500 Vermilion River near Vermilion, Ohio 41.382 -82.317 0.766 LTCR

04200000 East Branch Black River at Elyria, Ohio 41.348 -82.094 0.903 LTCR

04206211 Park Creek at Bath Center, Ohio 41.179 -81.636 0.583 LFPR

04207200 Tinkers Creek at Bedford, Ohio 41.384 -81.527 0.420 LTCR

04209000 Chagrin River at Willoughby, Ohio 41.631 -81.403 0.427 LTCR

04209500 Grand River near North Bristol, Ohio 41.413 -80.912 0.661 LFPR

04210000 Phelps Creek near Windsor, Ohio 41.516 -80.935 0.735 LTCR

04210500 Grand River near Rome, Ohio 41.606 -80.894 0.653 LFPR

04212000 Grand River near Madison, Ohio 41.741 -81.046 0.802 LTCR

04212100 Grand River near Painesville, Ohio 41.719 -81.228 0.633 LTCR

Table 1-1. Streamflow-variability index (SVI) values for locations in Ohio and adjacent States used for SVI-related analyses.—

Continued

[Streamflow-variability index, in units of base-10 logarithms of cubic feet per second; LTCR, long-term continuous record; LFPR, low-flow partial record]
Appendix 1 25

Table 1-1. Streamflow-variability index (SVI) values for locations in Ohio and adjacent States used for SVI-related analyses.—

Continued

[Streamflow-variability index, in units of base-10 logarithms of cubic feet per second; LTCR, long-term continuous record; LFPR, low-flow partial record]

Station number Station name Decimal 

latitude

Decimal 

longitude

Streamflowvariability 

index

Site type

04212500 Ashtabula River near Ashtabula, Ohio 41.856 -80.762 1.062 LTCR

04213000 Conneaut Creek at Conneaut, Ohio 41.927 -80.604 0.626 LTCR
26 Methods for Estimating Selected Low-Flow Statistics and Development of Annual Flow-Duration Statistics for Ohio

Figure 1-1. Scatter plots of regression residuals as a function of predicted low-flow yields. A, 1-day, 10-year. B, 7-day, 10-year. 

C, 30-day, 10-year. D, 90-day, 10-year. E, 80-percent duration low-flow yields.
Appendix 2 27

Appendix 2. Basin Characteristics Tested for Use in Low-Flow Regression

Analyses in Ohio

Location Variables

Latitude of basin centroid (Latc)—latitude of basin centroid, 

in decimal degrees.

Longitude of basin centroid (Longc)—longitude of basin 

centroid, in decimal degrees. Although all decimal longitudes 

in the study are west of the Prime Meridian and conventionally 

expressed as negative values, they were converted to positive 

values for the regression analyses.

Hydrologic Variables

Streamflow-variability index (SVI)—streamflow-variability 

index at the outlet of the basin (index value)—determined by 

interpolating a grid (with 1,000 ft2 cells) from at-site values 

for the streamflow-variability index computed for 163 rural, 

unregulated streamflow-gaging stations in Ohio and nearby 

areas of adjacent States. Grid interpolation was done using 

an inverse distance-weighting (IDW) technique in the Spatial 

Analyst extension of ArcInfo. Interpolation was based on the 

12 nearest neighboring streamflow-gaging stations. For further 

discussion on streamflow-variability index, see Koltun and 

Whitehead (2002).

Slope10-85 (SL10-85)—channel slope, in feet per mile—computed 

by (1) determining the longest flow path from the point of 

interest to a topographic divide (which generally corresponded 

to the basin divide), (2) determining the elevation at 10 

percent of the distance along the longest flow path upstream 

from the point at which the flow statistic is desired (E10), 

(3) determining the elevation at 85 percent of the distance 

along the longest flow path upstream from the point at which 

the flow statistic is desired (E85), (4) determining the length of 

the stream segment between points 10 and 85 percent of the 

distance along the longest flow path upstream from the point at 

which the flow statistic is desired (L10-85), and then (5) dividing 

the change in elevation (E85-E10) by L10-85. 

Drainage area (DA_SS)—area, in square miles—determined 

by use of the StreamStats application for Ohio (Koltun and 

others, 2006). StreamStats uses a specially processed digital 

elevation model to determine drainage areas. StreamStats will 

compute drainage areas that are comparable to map-based 

determinations in most cases; however, limitations associated 

with digital elevation model resolution and (or) scale, as well 

as other possible factors, may result in erroneous drainage 

area determinations. It is the user’s responsibility to verify that 

the drainage boundaries (and consequently the drainage area) 

derived by StreamStats are correct.

Longest flow path (LFPath)—flow path, the length, in 

miles—computed by determining the longest flow path from 

the point of interest to a topographic divide (which generally 

corresponded to the basin divide). StreamStats determines 

the longest flow path based on a specially processed digital 

elevation model that includes the streams of the 1:100,000 

National Hydrography Dataset (U.S. Geological Survey, 

2004).

Land-Cover Variables

Agriculture (Agric)—percentage of the basin classified 

as agriculture—determined by (1) summing the areas of 

the 2001 National Land Cover Dataset (NLCD) grid cells 

(U.S. Geological Survey, 2007) contained within the basin 

boundary that are classified as pasture/hay or cultivated crops 

(land-cover class codes 81 and 82, respectively), (2) dividing 

by the area of the basin, and then (3) multiplying by 100.

Impervious (Imperv)—percentage of the basin classified as 

having impervious surfaces—determined by (1) summing the 

per-pixel estimates of the imperviousness of the land cover 

for all the areas of the 2001 NLCD (U.S. Geological Survey, 

2007) contained within the basin boundary, (2) dividing by 

the number of cells in the basin, and then (3) multiplying by 

100.

Open water (OpenWater)—percentage of the basin classified 

as open water—determined by (1) summing the areas of 

the 2001 NLCD grid cells (U.S. Geological Survey, 2007) 

contained within the basin boundary that are classified as open 

water (land-cover class code 1), (2) dividing by the area of the 

basin, and then (3) multiplying by 100.

Storage (W)—percentage of the basin classified as water and 

wetlands—determined by (1) summing the areas of the 2001 

NLCD grid cells (U.S. Geological Survey, 2007) contained 

within the basin boundary that are classified as water, woody 

wetlands, and emergent herbaceous wetlands (land-cover class 

codes 11, 90, and 95, respectively), (2) dividing by the area of 

the basin, and then (3) multiplying by 100.

Wetland (Wetland)—percentage of the basin classified as 

wetlands—determined by (1) summing the areas of the 2001 

NLCD grid cells (U.S. Geological Survey, 2007) contained 

within the basin boundary that are classified as woody 

wetlands and emergent herbaceous wetlands (land-cover class 

codes 90 and 95, respectively), (2) dividing by the area of the 

basin, and then (3) multiplying by 100.
28 Methods for Estimating Selected Low-Flow Statistics and Development of Annual Flow-Duration Statistics for Ohio

Vegetated (Veg)—percentage of the basin classified as 

vegetated—determined by (1) summing the areas of the 2001 

NLCD grid cells (U.S. Geological Survey, 2007) contained 

within the basin boundary that are classified as deciduous 

forest, evergreen forest, mixed forest, developed, open space 

(lawn grasses), shrub/scrub, and grassland/herbaceous (landcover class codes 41, 42, 43, 21, 52, and 71 respectively), 

(2) dividing by the area of the basin, and then (3) multiplying 

by 100.

Forest (Forest)—percentage of the basin classified as forest—

determined by (1) summing the areas of the 2001 NLCD 

grid cells (U.S. Geological Survey, 2007) contained within 

the basin boundary that are classified as deciduous forest, 

evergreen forest, or mixed forest (land-cover class codes 41, 

42, and 43 respectively), (2) dividing by the area of the basin, 

and then (3) multiplying by 100.

Tree canopy (TreeCanopy)—percentage of the basin 

classified as having tree canopy—determined by (1) summing 

the per-pixel density of the tree cover of the 2001 NLCD 

(U.S. Geological Survey, 2007) contained within the basin 

boundary, (2) dividing by the number of cells in the basin, and 

then (3) multiplying by 100.

Geologic Variables

Primary rock carbonate or evaporite (CarbEvap1)—

percentage of the basin classified as carbonate or evaporite for 

the primary rock type—determined by (1) summing the areas 

of the Preliminary Integrated Geologic Map Databases for the 

United States (Nicholson and others, 2005a; Nicholson and 

others, 2005b; Dicken and others, 2005) contained within the 

basin boundary that are classified as carbonate or evaporite 

rock for the primary rock type, (2) dividing by the area of the 

basin, and then (3) multiplying by 100.

Primary/secondary rock carbonate or evaporite rock 

(CarbEvap12)—percentage of the basin classified as 

carbonate or evaporite for the primary or secondary rock 

type—determined by (1) summing the areas of the Preliminary 

Integrated Geologic Map Databases for the United States 

(Nicholson and others, 2005a; Nicholson and others, 2005b; 

Dicken and others, 2005) contained within the basin boundary 

that are classified as carbonate or evaporite rock for the 

primary or secondary rock type, (2) dividing by the area of the 

basin, and then (3) multiplying by 100.

Known karst (KarstKnown)—percentage of the basin 

classified as known karst areas—determined by (1) summing 

the areas of the State Geological Survey karst maps (Pavey 

and others, 1999; Shaffer and others, 2007) contained 

within the basin boundary that are classified as known karst, 

(2) dividing by the area of the basin, and then (3) multiplying 

by 100.

Probable karst (KarstProb)—percentage of the basin 

classified as probable karst areas—determined by (1) summing 

the areas of the State Geological Survey karst maps (Pavey 

and others, 1999; Shaffer and others, 2007; Michigan 

Department of Environmental Quality and others, 2004) 

contained within the basin boundary that are classified as 

probable karst, (2) dividing by the area of the basin, and then 

(3) multiplying by 100.

Drift thickness 0–50 feet (Drift_gt50 )—percentage of the 

basin classified as having a 0–50 feet glacial-drift thickness—

determined by (1) standardizing and summing the areas 

of the State Geological Survey drift thickness maps (Ohio 

Department of Natural Resources, 2000; Dintaman and Gray, 

2002; Michigan Department of Environmental Quality and 

others, 2004) contained within the basin boundary that are 

classified as having drift thickness of 0–50 feet, (2) dividing 

by the area of the basin, and then (3) multiplying by 100.

Drift thickness greater than 50 feet (Drift_0_50)—

percentage of the basin classified as having greater than 50 feet 

glacial-drift thickness—determined by (1) standardizing 

and summing the areas of the State Geological Survey drift 

thickness maps (Ohio Department of Natural Resources, 

2000; Dintaman and Gray, 2002; Michigan Department of 

Environmental Quality and others, 2004) contained within the 

basin boundary that are classified as having drift thickness of 

greater than 50 feet, (2) dividing by the area of the basin, and 

then (3) multiplying by 100.

Glaciated (Glaciated)—percentage of the basin classified 

as having been glaciated—determined by (1) summing the 

glaciated areas (Soller and Packard, 1998) contained within 

the basin boundary that are classified as having been glaciated, 

(2) dividing by the area of the basin, and then (3) multiplying 

by 100.

Soil Variables

Depth to water table (DpthWatTab)—area-weighted 

average STATSGO2 depth to water table, in centimeters—

determined by (1) multiplying each depth value, aggregated 

by dominant component, of the 2006 U.S. General Soil Map 

(STATSGO2) (U.S. Department of Agriculture–National 

Resources Conservation Service, 2006) as defined by the 

NRCS Soil Data Viewer 5.2 (U.S. Department of Agriculture–

National Resources Conservation Service, 2008) by its area of 

the basin, (2) summing those values, and then (3) dividing by 

the total area of the basin.

Hydrologic soil group percentages (SoilGroupA, 

SoilGroupB, SoilGroupC, SoilGroupD, SoilGroupCD, or 

SoilGroupBD)—percentage of basin classified in each of 

the six STATSGO2 soil groups—determined by (1) summing 

the gridded areas of the 2006 U.S. General Soil Map 
Appendix 2 29

(STATSGO2) (U.S. Department of Agriculture–National 

Resources Conservation Service, 2006) contained within the 

basin boundary that are classified as soil group A, B, C, D, 

CD, or BD, aggregated by dominant component, as defined 

by the Natural Resources Conversation Service (NRCS) Soil 

Data Viewer 5.2 (U.S. Department of Agriculture–National 

Resources Conservation Service, 2008), (2) dividing by the 

area of the basin, and then (3) multiplying by 100.

Mean hydrologic soil group index (SoilGroupMean)—area 

weighted average STATSGO2 soil group index—determined 

by (1) assigning each soil group, aggregated by dominant 

component, of the 2006 U.S. General Soil Map (STATSGO2) 

(U.S. Department of Agriculture–National Resources 

Conservation Service, 2006) as defined by the NRCS Soil 

Data Viewer 5.2 (U.S. Department of Agriculture–National 

Resources Conservation Service, 2008) a numeric value: 

A[1], B[3], C or BD[5], CD[6], and D[7], (2) multiplying 

each numeric class by its area of the basin, (3) summing those 

values, and then (4) dividing by the total area of the basin. 

Soil drainage class percentages (DrainCl1, DrainCl2, 

DrainCl3, DrainCl4, DrainCl5)—percentage of basin 

classified in each of the five STATSGO2 soil drainage 

classes—determined by (1) summing the gridded areas of the 

2006 U.S. General Soil Map (STATSGO2) (U.S. Department 

of Agriculture–National Resources Conservation Service, 

2006), aggregated by dominant component as defined by the 

NRCS Soil Data Viewer 5.2 (U.S. Department of Agriculture–

National Resources Conservation Service, 2008) contained 

within the basin boundary that are classified as drainage class 

Well drained, Moderately well drained, Somewhat poorly 

drained, Poorly drained, or Very poorly drained, (2) dividing 

by the area of the basin, and then (3) multiplying by 100.

Mean soil drainage class index (DrainClMean)—area 

weighted average STATSGO2 soil group index—determined 

by (1) assigning each soil drainage class of the 2006 

U.S. General Soil Map (STATSGO2) (U.S. Department 

of Agriculture–National Resources Conservation Service, 

2006) as defined by the NRCS Soil Data Viewer 5.2 

(U.S. Department of Agriculture–National Resources 

Conservation Service, 2008) a numeric value: well drained 

[1], Moderately well drained [2] Somewhat poorly drained [3], 

Poorly drained [4], or Very poorly drained [5], (2) multiplying 

each numeric class by its area of the basin, (3) summing those 

values, and then (4) dividing by the total area of the basin. 

Climatic Variables

Mean annual precipitation 1 at the basin centroid 

(Precip1)—the value, in inches, of the grid cell from 

Whitehead’s (2002) rasterized triangular irregular network of 

Harstine’s (1991) isoline map of mean annual precipitation for 

the period 1931–80 that is collocated with the basin centroid.

Mean annual precipitation 2 at the basin centroid 

(Precip2)—the value, in inches, of the grid cell from the 

Parameter-elevation Regressions on Independent Slopes 

Model (PRISM) dataset of mean annual precipitation for the 

period 1971–2000 (PRISM Climate Group, 2006a) that is 

collocated with the basin centroid. 

Basin-mean annual precipitation (MeanAnnP)—the value, 

in inches, determined by summing and averaging grid-cell 

values from the 1971–2000 mean annual precipitation PRISM 

dataset (PRISM Climate Group, 2006a) that are contained 

within the basin boundary. 

Basin-mean July precipitation (MeanJulP)—the value, in 

inches, determined by summing and averaging grid-cell values 

from the 1971–2000 mean July temperature PRISM dataset 

(PRISM Climate Group, 2006a) that are located within the 

basin boundary. 

Basin-minimum Autumn precipitation (MinAutP)—the 

value, in inches, determined by (1) summing, for each grid 

cell, the values assigned to the average minimum September, 

October, and November grid cells from the 1971–2000 

monthly average minimum precipitation PRISM datasets 

(PRISM Climate Group, 2006a) that are located within the 

basin boundary, and (2) selecting the minimum value of those 

grid-cell sums.

Basin-mean minimum Autumn precipitation

(MinAutP2)—the value, in inches, determined by 

(1) summing, for each grid cell, the values assigned to the 

average minimum September, October, and November 

grid cells from the 1971–2000 monthly average minimum 

precipitation PRISM datasets (PRISM Climate Group, 2006a) 

that are located within the basin boundary, and (2) dividing by 

the number of cells in the basin.

Basin-maximum Autumn temperature (MaxAutT)—the 

value, in degrees F, determined by (1) for each grid cell 

located within the basin, selecting the maximum temperature 

value from the average maximum September, October, and 

November temperature grids from the 1971–2000 PRISM 

dataset (PRISM Climate Group, 2006b), and (2) selecting the 

largest of the grid-cell maximum values.

Basin-mean maximum Autumn temperature

(MaxAutT2)—the value, in degrees F, determined by (1) for 

each grid cell located within the basin, selecting the maximum 

temperature value from the average maximum September, 

October, and November temperature grids from the 1971–

2000 PRISM datasets (PRISM Climate Group, 2006b), 

(2) summing the maximum values for each grid cell, and then, 

(3) dividing by the number of cells in the basin.

Table 2–1. Basin characteristics determined for selected 

streamgages in Ohio and adjacent States. (Available in Excel 

format. Click here to open table.
30 Methods for Estimating Selected Low-Flow Statistics and Development of Annual Flow-Duration Statistics for Ohio

References Cited

Dicken, C.L., Nicholson, S.W., Horton, J.D., Kinney, S.A., 

Gunther, Gregory, Foose, M.P., and Mueller, J.A.L., 2005, 

Preliminary integrated geologic map databases for the 

United States—Delaware, Maryland, New York, Pennsylvania, and Virginia: U.S. Geological Survey Open-File 

Report 2005–1325, ver. 1.1, accessed November 18, 2009, 

at http://pubs.usgs.gov/of/2005/1325/. 

Dintaman, C.R., and Gray, H.H., 2002, Thickness ranges of 

unconsolidated deposits in Indiana: Indiana Geological 

Survey digital data, 1:500,000, accessed July 27, 2009, at 

http://inmap.indiana.edu/download.html.

Harstine, L.J., 1991, Hydrologic atlas for Ohio—Average 

annual precipitation, temperature, streamflow, and water 

loss for a 50 year period, 1931–1980: Ohio Department 

of Natural Resources, Division of Water, Water Inventory 

Report 28, 13 p., 4pl.

Koltun, G.F., Kula, S.P., and Puskas, B.M., 2006, A streamflow statistics (StreamStats) Web application for Ohio: 

U.S. Geological Survey Scientific Investigations Report 

2006–5312, 62 p.

Koltun, G.F., and Whitehead, M.T., 2002, Techniques for estimating selected streamflow characteristics of rural unregulated streams in Ohio: U.S. Geological Survey WaterResources Investigations Report 2002–4068, 50 p.

Michigan Department of Environmental Quality, U.S. Geological Survey, and Michigan State University, 2004, Aquifer 

characteristics of glacial drift—Data based on digitizing the 

1981 Hydrological Atlas of Michigan—Plate 26, accessed 

August 4, 2009, at http://gwmap.rsgis.msu.edu.

Nicholson, S.W., Dicken, C.L., Foose, M.P., and Mueller, J.A.L., 2005a, Preliminary integrated geologic map 

databases for the United States—Minnesota, Wisconsin, 

Michigan, Illinois, and Indiana: U.S. Geological Survey 

Open-File Report 2004–1355, ver. 1.1, accessed November 

18, 2009, at http://pubs.usgs.gov/of/2004/1355/. 

Nicholson, S.W., Dicken, C.L., Horton, J.D., Labay, K.A., 

Foose, M.P., and Mueller, J.A.L., 2005b, Preliminary integrated geologic map databases for the United States—Kentucky, Ohio, Tennessee, and West Virginia: U. S. Geological 

Survey Open-File Report 2005–1324, ver. 1.1, accessed 

July 28, 2009, at http://pubs.usgs.gov/of/2005/1324/. 

Ohio Department of Natural Resources, 2000, Unconsolidated aquifers of Ohio, accessed August 4, 2009, at 

http://www.dnr.state.oh.us/water/tabid/4230/Default.aspx. 

Pavey, R.R., Hull, D.N., Brockman, C.S., Schumacher, G.A., 

Stith, D.A., Swinford, E.M., Sole, T.L., Vorbau, K.E., Kallini, K.D., Evans, E.E., Slucher, E.R., and Van Horn, R.G., 

1999, Known and probable karst in Ohio (revised 10/2007, 

5/2006, 2002): Ohio Division of Geological Survey 

Map EG-1, scale 1:500,000, 1 map and GIS files. 

PRISM Climate Group at Oregon State University, 

2006a, United States average monthly or annual precipitation, 1971–2000, accessed April 29, 2010, at 

http://www.prism.oregonstate.edu/products/matrix.phtml. 

PRISM Climate Group at Oregon State University, 2006b, 

United States average monthly or annual maximum 

temperature, 1971–2000, accessed April 29, 2010, at 

http://www.prism.oregonstate.edu/products/matrix.

phtml?vartype=tmax.

Shaffer, N.R., Sowder, K.H., Weibel, C.P., Wolfe, M.E., and 

Paylor, R.L., 2007, Map showing industrial minerals operations and carbonate regions affected by solution features in 

Illinois, Indiana, Kentucky, and Ohio: Indiana Geological 

Survey Open-File Study 07–02, scale: 1:1,000,000.

Soller, D.R., and Packard, P.H., 1998, Digital representation 

of a map showing the thickness and character of quaternary 

sediments in the glaciated United States East of the Rocky 

Mountains: U.S. Geological Survey Digital Data Series 

DDS-38. 

U.S. Department of Agriculture–Natural Resources Conservation Service, 2006, U.S. General Soil Map (STATSGO2), 

accessed July 20, 2009, at http://soildatamart.nrcs.usda.gov.

U.S. Department of Agriculture–Natural Resources Conservation Service, 2008, Soil Data Viewer 5.2 User Guide, 

accessed August 20, 2011, at ftp://ftp-fc.sc.egov.usda.gov/

NSSC/Soil_Data_Viewer/Soil_Data_Viewer_5_2_User_

Guide.pdf.

U.S. Geological Survey, 2004, The National Hydrography 

Dataset (NHD), 1:100,000, accessed June 3, 2006, at 

http://nhd.usgs.gov.

U.S. Geological Survey, 2007, National Land Cover Database 2001 (NLCD2001), ver. 1.0, accessed July 6, 2009, at 

http://www.mrlc.gov/nlcd2001_downloads.php.

Whitehead, M.T., 2002, Mean annual precipitation for Ohio, 

1931–80: U.S. Geological Survey data, accessed June 3, 

2006, at http://water.usgs.gov/lookup/getspatial?raintin. 
Appendix 3 31

Appendix 3. Annual 1-Day and 7-Day Mean Flow-Duration Results for Sites 

with Streamflows that have No or Minimal Regulation

03089500 Mill Creek near Berlin Center, Ohio

Years analyzed = 29

Climatic year range = 1942–70

[APEE, annual percentage equaled or exceeded; ft3/s, cubic foot per second]

Daily mean streamflow (ft3/s) that was equaled or exceeded the indicated percentage of time at APEE level

APEE 95 90 80 70 50 30 20 10 5

1 139. 179. 199. 217. 234. 300. 329. 385. 476.

2 76.2 94.4 101. 123. 162. 194. 225. 273. 292.

5 34.7 42.0 45.4 57.1 69.5 94.8 101. 114. 130.

10 15.0 19.4 24.8 27.0 32.0 44.3 48.8 63.0 72.8

20 4.84 8.96 10.0 11.0 15.0 20.0 23.2 26.0 28.3

25 3.23 6.00 7.03 8.40 10.0 14.5 18.0 19.5 21.0

30 2.30 4.00 4.70 5.70 8.00 11.0 13.0 15.0 17.0

40 1.68 2.00 2.60 3.00 4.26 6.80 8.06 8.80 11.8

50 1.05 1.20 1.40 1.90 2.60 4.00 5.00 6.40 7.80

60 0.75 0.84 1.00 1.20 1.80 2.48 2.94 4.90 5.25

70 0.50 0.60 0.70 0.80 1.20 1.31 1.70 3.40 3.79

75 0.40 0.40 0.56 0.60 0.90 1.20 1.40 2.28 3.13

80 0.30 0.40 0.40 0.50 0.80 1.00 1.10 1.64 2.42

90 0.10 0.19 0.20 0.30 0.40 0.60 0.80 1.00 1.75

95 0.05 0.10 0.10 0.20 0.30 0.50 0.55 0.80 1.50

98 0.00 0.00 0.10 0.10 0.21 0.40 0.50 0.70 1.32

99 0.00 0.00 0.03 0.10 0.20 0.33 0.47 0.60 1.23

7-day mean streamflow (ft3/s) that was equaled or exceeded the indicated percentage of time at APEE level

APEE 95 90 80 70 50 30 20 10 5

1 80.1 91.7 103. 105. 135. 166. 231. 261. 300.

2 54.9 57.9 82.1 90.4 105. 127. 139. 149. 177.

5 38.5 50.1 58.0 63.3 73.7 90.1 101. 120. 138.

10 19.4 25.6 31.3 38.3 50.4 59.4 68.1 78.3 80.0

20 5.64 9.86 12.0 14.4 21.7 32.3 33.5 39.0 51.9

25 3.37 6.93 8.46 9.57 16.4 22.1 28.0 31.5 35.5

30 2.60 4.23 5.94 7.57 11.1 16.7 20.4 23.9 24.8

40 1.71 1.93 2.89 3.24 5.11 9.86 11.6 16.3 18.9

50 1.19 1.30 1.56 2.27 3.17 4.51 7.69 10.2 11.5

60 0.81 0.96 1.13 1.56 2.17 3.09 4.00 6.81 7.76

70 0.51 0.70 0.80 0.93 1.44 1.84 2.31 4.89 5.46

75 0.42 0.46 0.63 0.72 1.27 1.46 1.71 4.29 4.42

80 0.34 0.40 0.49 0.54 0.87 1.19 1.40 2.71 3.35

90 0.19 0.20 0.26 0.31 0.47 0.88 0.92 1.10 1.92

95 0.07 0.11 0.16 0.24 0.36 0.59 0.71 0.93 1.79

98 0.03 0.06 0.08 0.16 0.27 0.45 0.50 0.77 1.58

99 0.01 0.03 0.04 0.11 0.23 0.39 0.49 0.67 1.46
32 Methods for Estimating Selected Low-Flow Statistics and Development of Annual Flow-Duration Statistics for Ohio

03092000 Kale Creek near Pricetown, Ohio

Years analyzed = 51

Climatic year range = 1942–92

[APEE, annual percentage equaled or exceeded; ft3/s, cubic foot per second]

Daily mean streamflow (ft3/s) that was equaled or exceeded the indicated percentage of time at APEE level

APEE 98 95 90 80 50 20 10 5 2

1 75.4 182. 211. 261. 367. 494. 577. 727. 883.

2 59.7 105. 122. 151. 245. 311. 401. 446. 492.

5 38.7 39.9 54.4 68.4 104. 144. 165. 189. 221.

10 18.0 21.2 25.0 31.0 46.2 76.4 89.1 94.6 97.9

20 5.06 6.65 9.02 12.9 21.6 29.8 35.8 40.9 43.9

25 3.51 4.30 5.21 8.64 13.5 21.0 26.8 28.8 35.8

30 2.60 2.65 3.53 6.13 10.2 16.6 19.2 20.9 28.7

40 1.11 1.52 1.81 2.98 6.32 10.4 11.2 13.8 17.9

50 0.70 0.80 1.01 1.42 3.50 6.90 7.50 9.08 12.9

60 0.34 0.40 0.60 0.80 2.00 4.56 5.60 7.00 9.72

70 0.10 0.21 0.30 0.40 1.20 2.59 4.12 5.15 6.58

75 0.10 0.18 0.20 0.30 0.81 2.23 3.40 4.13 5.26

80 0.04 0.10 0.20 0.23 0.59 1.76 2.68 3.16 3.70

90 0.00 0.06 0.10 0.10 0.30 0.98 1.43 1.75 2.19

95 0.00 0.02 0.07 0.10 0.20 0.73 0.93 1.16 1.82

98 0.00 0.00 0.00 0.05 0.13 0.49 0.80 0.94 1.39

99 0.00 0.00 0.00 0.03 0.11 0.36 0.70 0.91 1.26

7-day mean streamflow (ft3/s) that was equaled or exceeded the indicated percentage of time at APEE level

APEE 98 95 90 80 50 20 10 5 2

1 53.0 80.3 109. 139. 178. 233. 286. 337. 359.

2 41.1 69.5 90.9 119. 142. 195. 216. 268. 311.

5 32.2 53.2 61.8 77.1 105. 141. 156. 180. 197.

10 21.9 25.2 30.3 45.4 68.1 96.0 103. 114. 130.

20 5.40 9.02 13.5 19.2 33.1 53.2 61.9 67.0 72.9

25 4.12 4.90 7.27 13.5 21.9 40.2 48.8 52.0 59.1

30 2.85 3.37 4.43 9.79 16.6 31.8 37.2 39.7 45.2

40 1.52 1.68 2.19 3.77 8.80 17.1 21.2 29.0 30.6

50 0.82 0.91 1.37 1.71 4.57 9.60 12.5 18.1 23.3

60 0.43 0.57 0.64 0.90 2.54 6.35 7.48 11.9 15.7

70 0.12 0.25 0.35 0.45 1.49 3.79 5.36 8.39 11.7

75 0.06 0.20 0.27 0.35 0.88 3.26 4.27 6.49 9.05

80 0.05 0.14 0.20 0.25 0.67 2.35 3.45 4.03 7.36

90 0.00 0.06 0.10 0.14 0.34 1.19 1.65 2.34 3.73

95 0.00 0.05 0.07 0.10 0.22 0.85 1.06 1.62 2.10

98 0.00 0.02 0.05 0.06 0.16 0.66 0.90 1.10 1.79

99 0.00 0.00 0.02 0.04 0.14 0.59 0.76 1.01 1.54
Appendix 3 33

03092090 West Branch Mahoning River near Ravenna, Ohio

Years analyzed = 27

Climatic year range = 1966–92

[APEE, annual percentage equaled or exceeded; ft3/s, cubic foot per second]

Daily mean streamflow (ft3/s) that was equaled or exceeded the indicated percentage of time at APEE level

APEE 95 90 80 70 50 30 20 10 5

1 127. 190. 218. 256. 287. 366. 391. 451. 475.

2 87.8 119. 160. 175. 213. 244. 250. 304. 353.

5 52.9 69.6 80.2 83.8 116. 149. 166. 177. 198.

10 30.3 39.5 44.4 47.7 65.0 78.4 89.8 107. 112.

20 16.8 20.4 24.9 26.3 32.0 38.1 42.0 49.2 53.2

25 13.2 16.2 19.8 21.4 23.5 29.6 34.0 39.0 42.3

30 10.2 13.6 16.3 17.9 19.0 24.9 30.0 32.9 33.1

40 7.21 9.80 11.6 12.0 14.6 18.6 21.0 23.5 25.8

50 4.86 6.80 8.46 8.76 11.0 13.6 16.4 18.0 19.2

60 3.34 4.68 6.00 6.60 8.20 9.94 12.0 13.4 16.2

70 2.40 3.03 4.12 4.54 5.78 6.92 7.46 10.1 12.1

75 2.04 2.60 3.32 3.84 4.85 5.76 6.20 9.11 9.82

80 1.76 2.00 2.68 3.21 4.12 4.40 4.85 7.86 8.05

90 0.82 1.19 1.40 1.78 2.50 2.93 3.26 4.13 4.63

95 0.44 1.05 1.12 1.34 1.80 2.40 2.75 3.10 3.68

98 0.31 0.71 0.94 0.99 1.40 1.90 2.14 2.76 3.12

99 0.23 0.49 0.85 0.93 1.20 1.81 1.94 2.48 2.92

7-day mean streamflow (ft3/s) that was equaled or exceeded the indicated percentage of time at APEE level

APEE 95 90 80 70 50 30 20 10 5

1 78.2 91.1 126. 160. 181. 206. 219. 234. 268.

2 64.7 80.5 95.7 123. 136. 157. 175. 188. 203.

5 51.4 64.5 83.2 85.0 96.0 114. 128. 141. 151.

10 34.5 47.1 54.1 59.6 72.4 82.4 94.9 107. 116.

20 16.5 25.4 29.6 30.7 41.0 54.5 60.2 70.0 79.8

25 12.7 20.9 24.4 25.7 34.3 47.4 50.2 57.7 60.0

30 10.4 16.6 19.7 21.7 25.7 37.2 41.0 47.3 49.1

40 7.62 10.2 13.2 14.6 17.3 26.3 29.1 35.7 37.7

50 5.67 7.63 9.50 10.5 12.8 17.3 20.6 25.4 27.0

60 3.75 5.48 6.99 8.57 9.74 12.4 14.8 18.4 20.9

70 2.50 3.29 4.77 5.30 7.08 7.95 9.54 12.4 17.1

75 2.15 2.84 3.93 4.63 5.80 6.57 7.99 10.4 14.9

80 1.91 2.48 3.24 3.84 4.61 5.54 6.06 8.51 12.0

90 1.30 1.51 1.86 2.17 3.24 3.60 3.94 4.91 6.44

95 0.71 1.07 1.25 1.46 2.33 2.88 3.23 3.71 4.37

98 0.43 0.89 1.06 1.13 2.01 2.25 2.71 3.38 3.82

99 0.33 0.62 0.97 1.05 1.64 2.07 2.35 3.09 3.51
34 Methods for Estimating Selected Low-Flow Statistics and Development of Annual Flow-Duration Statistics for Ohio

03102950 Pymatuning Creek at Kinsman, Ohio

Years analyzed = 28

Climatic year range = 1966–93

[APEE, annual percentage equaled or exceeded; ft3/s, cubic foot per second]

Daily mean streamflow (ft3/s) that was equaled or exceeded the indicated percentage of time at APEE level

APEE 95 90 80 70 50 30 20 10 5

1 466. 642. 746. 862. 985. 1030. 1110. 1240. 1470.

2 390. 550. 612. 635. 749. 799. 836. 855. 872.

5 290. 363. 408. 451. 514. 568. 623. 680. 707.

10 186. 240. 272. 281. 344. 407. 437. 501. 518.

20 87.6 117. 138. 178. 194. 228. 255. 274. 308.

25 65.4 95.8 106. 132. 154. 188. 207. 235. 269.

30 48.3 76.8 83.8 97.7 121. 155. 168. 201. 225.

40 31.9 47.6 57.8 68.1 79.6 98.9 112. 150. 158.

50 21.1 32.3 40.0 44.1 51.0 71.5 79.2 110. 114.

60 15.4 20.6 23.3 27.1 36.9 48.7 55.3 77.7 90.9

70 8.42 9.57 12.6 16.0 22.0 33.0 37.0 51.2 61.6

75 5.04 7.93 9.70 11.0 15.3 27.6 28.8 42.6 50.5

80 3.43 6.22 7.06 8.20 11.1 18.6 24.0 31.2 34.4

90 1.29 2.00 3.17 3.71 5.32 10.9 12.2 14.1 16.1

95 0.43 1.07 1.47 2.26 3.40 6.58 7.04 7.44 8.80

98 0.21 0.23 0.84 1.32 2.40 3.83 5.09 5.48 5.92

99 0.13 0.17 0.71 1.07 2.10 3.23 3.99 4.38 4.79

7-day mean streamflow (ft3/s) that was equaled or exceeded the indicated percentage of time at APEE level

APEE 95 90 80 70 50 30 20 10 5

1 321. 502. 546. 641. 766. 873. 904. 1070. 1160.

2 309. 442. 476. 535. 604. 705. 750. 807. 869.

5 251. 326. 380. 411. 446. 503. 530. 595. 615.

10 183. 219. 292. 299. 333. 368. 418. 443. 471.

20 94.4 126. 154. 170. 230. 252. 270. 300. 305.

25 65.4 101. 118. 140. 180. 200. 209. 258. 260.

30 49.9 73.6 91.6 113. 138. 169. 174. 225. 234.

40 33.0 50.5 63.0 75.0 88.0 118. 126. 174. 184.

50 21.2 34.8 42.8 49.7 57.6 83.3 92.0 136. 142.

60 15.3 20.1 25.7 31.5 39.7 55.5 63.3 104. 111.

70 9.80 10.6 16.1 19.5 22.9 37.7 45.9 70.2 78.1

75 5.37 8.41 11.0 14.1 17.7 31.6 36.3 55.6 59.7

80 3.65 6.54 7.59 9.53 11.9 22.7 27.3 41.1 43.8

90 1.38 2.15 3.84 4.27 6.23 14.0 15.2 16.9 20.1

95 0.64 1.17 2.27 2.68 3.87 7.65 8.27 10.2 11.6

98 0.26 0.35 0.93 1.80 3.06 4.51 5.78 6.91 8.48

99 0.21 0.24 0.81 1.40 2.62 4.09 5.33 5.66 6.84
Appendix 3 35

03109500 Little Beaver Creek near East Liverpool, Ohio

Years analyzed = 93

Climatic year range = 1916–2008

[APEE, annual percentage equaled or exceeded; ft3/s, cubic foot per second]

Daily mean streamflow (ft3/s) that was equaled or exceeded the indicated percentage of time at APEE level

APEE 98 95 90 80 50 20 10 5 2

1 1230. 2090. 2520. 2860. 4110. 5250. 6260. 7050. 9230.

2 960. 1290. 1940. 2120. 2940. 3910. 4520. 5030. 6730.

5 709. 876. 1110. 1300. 1830. 2440. 2740. 2920. 3330.

10 517. 643. 749. 866. 1230. 1540. 1740. 1900. 2110.

20 268. 372. 429. 494. 700. 936. 1040. 1150. 1260.

25 206. 301. 350. 403. 570. 767. 900. 1000. 1100.

30 161. 222. 289. 328. 479. 670. 765. 864. 962.

40 106. 134. 192. 225. 321. 494. 593. 674. 777.

50 67.6 98.7 127. 160. 245. 392. 453. 525. 665.

60 50.2 77.6 87.0 111. 176. 290. 343. 413. 566.

70 38.7 54.5 64.7 83.6 130. 206. 264. 314. 477.

75 35.0 48.0 54.7 69.8 110. 180. 221. 281. 434.

80 30.4 41.7 46.4 58.4 92.0 131. 182. 249. 391.

90 21.4 30.6 33.2 38.0 61.7 93.1 132. 175. 272.

95 17.5 24.5 26.4 31.8 47.4 78.6 106. 136. 207.

98 14.0 19.9 22.0 25.8 39.6 66.3 91.3 124. 172.

99 12.9 17.1 20.7 24.0 35.7 60.2 81.5 109. 155.

7-day mean streamflow (ft3/s) that was equaled or exceeded the indicated percentage of time at APEE level

APEE 98 95 90 80 50 20 10 5 2

1 970. 1340. 1740. 2040. 2820. 3970. 4450. 5060. 6230.

2 844. 1130. 1420. 1670. 2460. 2970. 3420. 3810. 4640.

5 700. 834. 1030. 1280. 1720. 2150. 2540. 2760. 3050.

10 496. 636. 759. 901. 1220. 1620. 1790. 2010. 2230.

20 278. 391. 429. 512. 802. 1040. 1240. 1390. 1530.

25 195. 320. 375. 431. 632. 890. 1010. 1190. 1280.

30 161. 241. 309. 341. 526. 777. 835. 1090. 1150.

40 107. 145. 201. 231. 358. 591. 669. 790. 911.

50 76.6 110. 131. 172. 270. 430. 520. 591. 733.

60 52.1 80.9 93.8 115. 189. 310. 399. 467. 612.

70 40.0 58.1 71.2 85.2 136. 236. 289. 337. 530.

75 37.3 52.2 58.7 72.5 120. 196. 232. 312. 487.

80 30.6 43.1 50.9 60.7 101. 155. 207. 287. 427.

90 24.3 31.2 35.3 40.7 64.6 103. 146. 210. 349.

95 17.8 26.6 30.2 34.2 50.4 86.3 120. 147. 232.

98 14.6 21.5 24.7 28.9 43.1 75.7 105. 137. 196.

99 14.0 20.6 23.0 26.2 40.0 69.4 93.9 133. 180.
36 Methods for Estimating Selected Low-Flow Statistics and Development of Annual Flow-Duration Statistics for Ohio

03110000 Yellow Creek near Hammondsville, Ohio

Years analyzed = 68

Climatic year range = 1941–2008

[APEE, annual percentage equaled or exceeded; ft3/s, cubic foot per second]

Daily mean streamflow (ft3/s) that was equaled or exceeded the indicated percentage of time at APEE level

APEE 98 95 90 80 50 20 10 5 2

1 594. 719. 832. 926. 1290. 1710. 1890. 2170. 2980.

2 406. 488. 618. 682. 863. 1170. 1350. 1490. 1740.

5 267. 325. 339. 425. 561. 734. 858. 916. 1170.

10 186. 223. 241. 288. 386. 464. 565. 586. 699.

20 104. 120. 131. 160. 235. 286. 317. 361. 403.

25 76.6 95.1 101. 126. 186. 248. 267. 313. 352.

30 49.4 68.1 81.1 102. 153. 206. 229. 265. 306.

40 27.6 39.3 54.0 69.4 104. 160. 181. 216. 239.

50 17.1 24.1 35.7 42.0 73.0 121. 146. 164. 192.

60 10.8 16.6 22.4 30.0 49.7 85.4 108. 130. 159.

70 7.44 10.5 15.0 20.0 35.9 59.6 73.8 100. 125.

75 6.03 8.63 12.0 16.0 28.5 46.0 61.5 87.9 114.

80 5.04 7.05 8.99 13.0 22.3 38.0 46.0 79.5 98.6

90 3.11 3.98 4.78 6.20 13.0 22.0 30.1 51.8 68.7

95 1.71 2.52 3.43 4.08 9.30 16.3 25.1 37.3 56.2

98 1.02 1.92 2.18 3.09 7.43 13.2 19.1 26.2 47.2

99 0.88 1.66 1.90 2.86 6.25 12.1 16.8 24.2 42.9

7-day mean streamflow (ft3/s) that was equaled or exceeded the indicated percentage of time at APEE level

APEE 98 95 90 80 50 20 10 5 2

1 419. 495. 521. 645. 871. 1150. 1440. 1650. 1800.

2 364. 406. 473. 558. 740. 865. 962. 1210. 1520.

5 281. 310. 347. 403. 554. 702. 776. 873. 1160.

10 184. 227. 242. 294. 408. 514. 579. 624. 738.

20 98.8 115. 143. 172. 269. 333. 372. 429. 464.

25 66.2 93.9 112. 133. 214. 281. 320. 369. 407.

30 49.5 69.1 83.6 106. 171. 232. 262. 325. 354.

40 31.0 42.3 57.6 77.4 115. 180. 204. 237. 278.

50 15.4 26.2 36.6 43.8 77.8 129. 161. 180. 217.

60 11.6 17.2 23.7 32.8 55.3 94.7 123. 143. 185.

70 7.69 12.0 17.6 21.3 39.9 64.5 81.6 113. 145.

75 6.76 9.54 13.4 18.5 31.5 54.3 69.0 101. 129.

80 5.84 7.47 10.2 13.3 25.9 41.9 54.5 87.0 117.

90 3.39 4.21 5.44 6.54 15.4 25.3 33.8 59.2 75.9

95 2.20 2.67 3.66 4.56 10.6 18.8 28.0 46.3 63.1

98 1.58 2.02 2.81 3.80 8.81 15.0 23.7 32.5 54.2

99 1.02 1.89 2.36 3.40 7.46 13.6 19.9 28.7 52.0
Appendix 3 37

03111500 Short Creek near Dillonvale, Ohio

Years analyzed = 67

Climatic year range = 1942–2008

[APEE, annual percentage equaled or exceeded; ft3/s, cubic foot per second]

Daily mean streamflow (ft3/s) that was equaled or exceeded the indicated percentage of time at APEE level

APEE 98 95 90 80 50 20 10 5 2

1 366. 410. 483. 541. 749. 1210. 1390. 1530. 2690.

2 278. 294. 337. 401. 542. 821. 925. 1180. 1420.

5 187. 200. 227. 254. 369. 480. 579. 715. 760.

10 136. 147. 167. 194. 265. 335. 408. 429. 479.

20 94.5 103. 111. 125. 176. 222. 271. 291. 315.

25 80.5 81.9 93.4 106. 148. 197. 235. 256. 287.

30 62.8 67.5 81.4 92.4 130. 178. 202. 233. 257.

40 37.7 43.8 55.5 68.6 99.2 143. 162. 195. 220.

50 25.7 34.6 42.4 50.0 71.0 114. 134. 153. 194.

60 19.1 28.6 30.0 37.4 58.4 91.7 113. 127. 171.

70 16.4 22.8 25.0 27.6 46.0 67.9 95.5 103. 141.

75 14.7 20.4 22.4 24.6 39.0 60.4 85.6 93.6 129.

80 13.4 19.0 19.3 21.6 36.0 52.2 73.2 85.8 118.

90 12.0 13.0 14.9 16.6 26.0 39.4 55.6 68.6 89.3

95 8.30 10.0 12.0 15.0 23.0 33.4 47.4 63.6 75.1

98 4.84 7.28 9.96 13.0 20.0 29.6 42.8 56.5 70.8

99 3.92 5.88 9.28 12.0 19.0 28.3 40.5 53.6 67.2

7-day mean streamflow (ft3/s) that was equaled or exceeded the indicated percentage of time at APEE level

APEE 98 95 90 80 50 20 10 5 2

1 249. 288. 313. 384. 573. 833. 972. 1340. 1470.

2 220. 262. 274. 327. 467. 685. 782. 872. 1210.

5 189. 194. 207. 244. 363. 481. 577. 655. 844.

10 139. 162. 166. 187. 269. 350. 430. 463. 482.

20 95.1 101. 114. 126. 185. 249. 296. 334. 348.

25 79.1 84.1 94.3 112. 155. 212. 248. 284. 311.

30 64.5 69.5 79.2 93.0 138. 189. 223. 250. 286.

40 37.7 45.6 59.6 70.2 103. 154. 178. 204. 245.

50 26.0 35.4 45.3 51.0 79.1 122. 146. 165. 212.

60 20.6 29.9 33.7 39.3 63.1 96.8 122. 138. 190.

70 17.1 24.2 27.1 29.9 48.3 75.8 102. 118. 164.

75 15.4 22.0 24.5 25.8 44.3 68.1 91.2 108. 147.

80 14.3 20.0 21.0 23.1 38.3 56.3 79.5 96.9 132.

90 12.4 13.6 16.8 18.2 28.3 42.0 61.5 77.9 104.

95 8.86 11.0 13.0 15.6 24.1 35.9 49.8 67.6 87.1

98 6.42 8.56 11.5 13.9 21.4 32.0 46.0 62.4 80.1

99 5.46 7.46 10.7 13.5 20.4 30.2 44.4 60.8 77.0
38 Methods for Estimating Selected Low-Flow Statistics and Development of Annual Flow-Duration Statistics for Ohio

03111548 Wheeling Creek below Blaine, Ohio

Years analyzed = 24

Climatic year range = 1983–2008

[APEE, annual percentage equaled or exceeded; ft3/s, cubic foot per second]

Daily mean streamflow (ft3/s) that was equaled or exceeded the indicated percentage of time at APEE level

APEE 95 90 80 70 50 30 20 10 5

1 428. 481. 526. 593. 720. 976. 1030. 1310. 2050.

2 324. 371. 378. 415. 539. 585. 645. 842. 1160.

5 170. 195. 216. 242. 316. 379. 386. 501. 644.

10 118. 139. 166. 180. 215. 250. 270. 325. 392.

20 88.0 98.6 106. 122. 143. 173. 176. 216. 248.

25 76.9 83.0 95.0 107. 126. 148. 159. 187. 224.

30 67.4 76.5 85.2 93.5 113. 131. 142. 165. 199.

40 49.0 59.6 66.0 71.9 89.8 103. 110. 143. 171.

50 38.0 40.5 52.0 57.0 71.0 84.0 92.0 121. 152.

60 30.8 33.7 41.4 46.0 54.7 69.0 73.0 103. 132.

70 26.5 29.0 32.0 37.4 42.0 50.4 64.0 86.0 105.

75 24.4 26.4 28.0 31.0 39.0 44.0 60.0 77.0 97.1

80 21.4 22.5 26.0 27.0 34.5 40.0 53.0 70.6 89.0

90 14.0 15.5 20.0 20.3 25.4 32.5 39.6 58.0 70.2

95 9.94 12.5 17.0 19.0 22.2 27.5 32.0 50.2 60.5

98 7.88 10.5 16.0 17.0 19.7 24.0 31.0 39.3 52.7

99 7.54 10.2 14.7 16.5 17.8 23.0 30.0 36.3 48.7

7-day mean streamflow (ft3/s) that was equaled or exceeded the indicated percentage of time at APEE level

APEE 95 90 80 70 50 30 20 10 5

1 290. 303. 344. 375. 481. 609. 729. 1090. 1220.

2 237. 255. 290. 328. 401. 472. 553. 756. 1030.

5 182. 195. 223. 247. 325. 372. 406. 515. 692.

10 127. 144. 172. 186. 222. 262. 286. 343. 388.

20 92.6 97.6 114. 130. 153. 178. 187. 235. 272.

25 77.6 82.9 100. 119. 133. 164. 169. 207. 253.

30 70.4 78.2 86.3 98.9 115. 146. 151. 193. 236.

40 52.0 61.8 68.3 74.9 90.7 111. 121. 163. 200.

50 41.2 44.1 52.6 62.1 74.4 95.0 100. 135. 167.

60 33.1 34.4 45.3 49.0 59.4 76.2 81.9 119. 145.

70 27.3 30.4 32.9 38.8 47.0 52.8 66.1 101. 120.

75 25.0 28.1 29.3 33.4 43.2 47.6 61.9 89.1 110.

80 23.1 24.1 26.6 28.7 37.6 41.7 55.9 78.9 98.4

90 15.4 18.5 20.9 22.2 28.3 34.6 40.4 64.7 80.6

95 10.1 12.5 18.4 19.9 24.6 30.9 33.4 58.5 67.0

98 8.20 11.1 17.1 18.9 21.8 25.9 32.0 48.7 61.8

99 7.83 10.6 16.0 18.0 19.4 25.0 31.9 40.8 59.9
Appendix 3 39

03114000 Captina Creek at Armstrongs Mills, Ohio

Years analyzed = 52

Climatic year range = 1927–2002

[APEE, annual percentage equaled or exceeded; ft3/s, cubic foot per second]

Daily mean streamflow (ft3/s) that was equaled or exceeded the indicated percentage of time at APEE level

APEE 98 95 90 80 50 20 10 5 2

1 344. 1020. 1120. 1170. 1530. 1980. 2380. 2700. 3360.

2 197. 667. 776. 848. 1070. 1320. 1480. 1730. 1800.

5 144. 320. 412. 481. 615. 754. 854. 966. 1090.

10 101. 185. 239. 289. 373. 469. 550. 571. 592.

20 34.5 110. 127. 150. 207. 284. 301. 342. 359.

25 30.3 84.9 100. 115. 165. 232. 254. 272. 326.

30 21.6 61.9 79.8 89.9 130. 191. 210. 232. 288.

40 11.0 36.4 47.9 57.8 91.8 140. 158. 182. 230.

50 5.59 20.0 30.6 37.6 62.5 103. 126. 153. 179.

60 2.20 9.58 16.0 21.5 38.6 71.4 93.0 119. 141.

70 0.96 4.15 6.28 11.6 23.8 37.9 62.4 82.7 108.

75 0.35 3.00 4.27 9.29 17.0 29.5 52.1 67.4 95.9

80 0.17 1.88 2.63 7.00 12.7 22.4 40.0 51.5 80.7

90 0.01 0.29 1.08 2.08 5.97 12.8 20.1 31.7 58.0

95 0.00 0.07 0.40 1.02 3.93 8.48 12.5 18.6 40.6

98 0.00 0.00 0.03 0.36 2.13 5.48 7.40 10.6 29.0

99 0.00 0.00 0.00 0.09 1.60 4.30 5.29 9.70 27.0

7-day mean streamflow (ft3/s) that was equaled or exceeded the indicated percentage of time at APEE level

APEE 98 95 90 80 50 20 10 5 2

1 202. 600. 655. 701. 928. 1380. 1720. 1760. 1870.

2 172. 498. 580. 632. 745. 999. 1090. 1190. 1290.

5 131. 329. 390. 461. 547. 724. 809. 944. 1060.

10 100. 199. 273. 327. 420. 511. 545. 609. 705.

20 36.9 120. 151. 182. 247. 307. 364. 413. 430.

25 26.6 88.5 115. 137. 197. 267. 320. 344. 372.

30 22.4 68.3 86.7 104. 159. 231. 271. 310. 338.

40 13.3 36.4 50.7 67.2 109. 174. 199. 231. 276.

50 6.25 20.8 32.5 42.4 77.2 123. 155. 185. 223.

60 3.10 10.9 17.5 26.1 48.0 81.1 117. 144. 170.

70 1.33 4.68 8.18 13.9 28.7 47.6 79.3 97.2 134.

75 0.69 3.17 5.29 10.2 21.2 35.5 61.2 82.7 116.

80 0.24 2.17 3.80 9.05 16.4 27.3 49.4 62.5 98.0

90 0.01 0.50 1.41 2.66 7.98 15.5 25.9 36.2 73.8

95 0.00 0.10 0.84 1.33 5.31 11.0 17.8 26.3 56.4

98 0.00 0.00 0.09 0.69 3.56 7.64 10.2 17.2 42.0

99 0.00 0.00 0.03 0.42 1.96 6.09 7.71 11.4 35.9
40 Methods for Estimating Selected Low-Flow Statistics and Development of Annual Flow-Duration Statistics for Ohio

03115400 Little Muskingum River at Bloomfield, Ohio

Years analyzed = 35

Climatic year range = 1959–2008

[APEE, annual percentage equaled or exceeded; ft3/s, cubic foot per second]

Daily mean streamflow (ft3/s) that was equaled or exceeded the indicated percentage of time at APEE level

APEE 95 90 80 70 50 30 20 10 5

1 1920. 2040. 2200. 2340. 2740. 3430. 3680. 4240. 5470.

2 1270. 1400. 1430. 1600. 1970. 2350. 2660. 2950. 4080.

5 680. 748. 830. 934. 1060. 1250. 1420. 1610. 1780.

10 354. 402. 460. 518. 579. 722. 816. 941. 1010.

20 184. 199. 220. 271. 311. 400. 444. 483. 579.

25 112. 136. 168. 221. 246. 342. 351. 396. 449.

30 81.2 99.4 134. 165. 200. 280. 297. 342. 379.

40 41.6 57.8 75.9 83.7 126. 186. 216. 257. 310.

50 22.4 28.5 40.2 44.0 81.0 117. 168. 199. 239.

60 10.3 13.8 19.8 24.6 50.0 73.5 115. 154. 179.

70 3.35 6.46 11.2 14.8 26.8 44.4 66.2 111. 124.

75 2.52 4.06 6.48 10.5 20.0 31.6 49.9 89.6 105.

80 1.84 2.75 4.20 5.16 13.0 22.6 38.8 69.7 83.9

90 0.56 0.73 1.47 2.10 4.72 9.32 18.9 32.2 52.4

95 0.23 0.42 0.80 1.16 3.73 6.14 9.88 19.7 40.0

98 0.08 0.19 0.40 0.71 2.47 4.13 5.35 9.59 26.4

99 0.05 0.08 0.32 0.56 2.10 3.08 4.00 8.22 19.8

7-day mean streamflow (ft3/s) that was equaled or exceeded the indicated percentage of time at APEE level

APEE 95 90 80 70 50 30 20 10 5

1 894. 980. 1210. 1470. 1730. 1970. 2380. 3280. 5150.

2 825. 895. 1120. 1220. 1320. 1570. 1790. 2230. 2880.

5 693. 699. 765. 854. 1050. 1090. 1150. 1490. 1800.

10 411. 497. 590. 598. 685. 805. 860. 959. 1150.

20 211. 244. 277. 365. 398. 522. 568. 632. 698.

25 115. 171. 221. 264. 317. 445. 487. 548. 608.

30 87.7 126. 150. 199. 252. 368. 403. 448. 505.

40 47.8 67.5 87.2 98.5 165. 226. 273. 345. 419.

50 27.5 33.2 44.7 49.5 93.0 156. 212. 259. 328.

60 12.5 16.8 22.5 28.5 61.4 95.7 143. 206. 246.

70 4.07 7.32 12.9 17.0 31.1 61.3 86.2 153. 174.

75 2.81 4.44 7.61 13.1 23.7 41.3 70.3 120. 142.

80 2.12 2.84 5.44 6.87 17.4 28.2 52.1 93.9 114.

90 0.61 0.88 1.57 2.42 6.74 11.8 24.8 45.4 68.0

95 0.28 0.47 0.92 1.36 3.97 7.92 12.1 26.7 50.3

98 0.16 0.27 0.46 0.84 3.40 6.03 8.76 13.4 35.7

99 0.11 0.23 0.40 0.65 2.63 4.73 6.16 12.0 26.1
Appendix 3 41

03117500 Sandy Creek at Waynesburg, Ohio

Years analyzed = 70

Climatic year range = 1939–2008

[APEE, annual percentage equaled or exceeded; ft3/s, cubic foot per second]

Daily mean streamflow (ft3/s) that was equaled or exceeded the indicated percentage of time at APEE level

APEE 98 95 90 80 50 20 10 5 2

1 756. 929. 1240. 1410. 1990. 2520. 2800. 3290. 4100.

2 617. 756. 863. 1170. 1440. 1850. 2170. 2330. 2880.

5 409. 477. 573. 651. 920. 1220. 1380. 1470. 1970.

10 292. 350. 401. 450. 633. 820. 922. 1040. 1290.

20 159. 188. 225. 257. 368. 509. 592. 664. 764.

25 106. 156. 190. 222. 303. 414. 491. 565. 638.

30 81.5 120. 154. 179. 263. 360. 417. 498. 570.

40 56.3 72.0 92.8 122. 197. 275. 338. 386. 458.

50 40.4 52.8 61.2 88.2 141. 205. 254. 304. 375.

60 31.5 40.2 46.0 62.1 108. 164. 199. 246. 319.

70 23.5 33.5 36.1 48.4 79.8 126. 150. 203. 262.

75 22.9 32.0 33.0 42.1 71.5 107. 132. 185. 232.

80 21.4 30.0 31.0 36.2 60.8 96.0 114. 168. 204.

90 19.0 23.6 25.0 29.0 44.8 68.8 89.2 132. 161.

95 15.5 20.2 22.0 24.7 38.0 57.3 79.6 106. 128.

98 14.1 17.7 20.0 23.0 33.2 52.9 74.8 85.0 110.

99 13.5 16.8 17.4 21.1 31.7 50.3 71.7 79.3 99.4

7-day mean streamflow (ft3/s) that was equaled or exceeded the indicated percentage of time at APEE level

APEE 98 95 90 80 50 20 10 5 2

1 572. 738. 897. 1100. 1470. 1940. 2170. 2500. 2930.

2 541. 666. 706. 892. 1180. 1520. 1720. 1780. 2190.

5 396. 455. 548. 676. 876. 1140. 1270. 1370. 1750.

10 281. 340. 415. 450. 630. 829. 968. 1060. 1230.

20 154. 183. 231. 266. 400. 562. 625. 734. 856.

25 105. 148. 195. 229. 335. 469. 532. 611. 742.

30 85.7 124. 159. 197. 294. 404. 463. 547. 629.

40 57.6 73.8 107. 126. 213. 303. 364. 436. 522.

50 41.8 58.0 64.6 93.5 153. 231. 293. 357. 438.

60 30.2 40.3 47.4 61.1 114. 181. 208. 296. 352.

70 24.6 34.4 36.8 49.7 84.9 133. 167. 233. 288.

75 23.0 31.7 33.8 42.2 73.6 119. 146. 214. 261.

80 21.8 29.4 31.4 38.4 64.6 102. 127. 192. 237.

90 18.5 23.8 25.6 29.7 47.7 74.4 94.3 145. 184.

95 16.2 20.8 22.7 25.7 39.1 63.8 81.3 118. 147.

98 14.9 19.0 21.2 24.8 35.1 56.1 77.0 95.6 121.

99 14.5 18.2 19.8 24.1 33.7 54.0 75.6 83.7 116.
42 Methods for Estimating Selected Low-Flow Statistics and Development of Annual Flow-Duration Statistics for Ohio

03119000 Sandy Creek at Sandyville, Ohio

Years analyzed = 23

Climatic year range = 1924–46

[APEE, annual percentage equaled or exceeded; ft3/s, cubic foot per second]

Daily mean streamflow (ft3/s) that was equaled or exceeded the indicated percentage of time at APEE level

APEE 95 90 80 70 50 30 20 10 5

1 1140. 2270. 2530. 2920. 3270. 4050. 4430. 5490. 7490.

2 897. 1700. 1870. 2130. 2400. 3230. 3730. 4260. 4710.

5 629. 1020. 1210. 1260. 1570. 1980. 2030. 2160. 2390.

10 471. 692. 752. 809. 1080. 1220. 1310. 1440. 1680.

20 268. 399. 447. 479. 656. 770. 830. 911. 1120.

25 226. 333. 376. 393. 555. 675. 693. 760. 932.

30 176. 268. 300. 314. 481. 554. 598. 663. 801.

40 135. 163. 210. 248. 354. 424. 461. 541. 658.

50 112. 129. 167. 187. 268. 326. 352. 423. 530.

60 96.8 109. 133. 155. 211. 247. 281. 324. 412.

70 89.8 99.3 117. 129. 174. 198. 206. 248. 298.

75 86.8 92.8 106. 114. 161. 178. 186. 205. 254.

80 83.3 88.2 93.0 105. 139. 156. 166. 171. 214.

90 72.8 74.6 81.6 89.3 115. 126. 136. 146. 158.

95 65.1 67.6 76.2 83.7 103. 113. 123. 132. 138.

98 57.4 59.7 72.3 80.2 98.0 103. 111. 118. 122.

99 53.4 56.9 71.6 74.3 90.0 98.3 102. 113. 118.

7-day mean streamflow (ft3/s) that was equaled or exceeded the indicated percentage of time at APEE level

APEE 95 90 80 70 50 30 20 10 5

1 883. 1390. 1700. 2330. 2950. 3150. 3630. 4080. 5940.

2 799. 1180. 1460. 1670. 2000. 2540. 2860. 3100. 4480.

5 576. 1010. 1130. 1240. 1380. 1800. 1890. 2190. 2380.

10 430. 727. 819. 879. 1070. 1250. 1330. 1430. 1650.

20 263. 386. 453. 537. 734. 850. 903. 1090. 1260.

25 224. 340. 369. 437. 632. 738. 772. 940. 1120.

30 185. 286. 308. 351. 516. 607. 657. 788. 935.

40 136. 167. 234. 273. 348. 459. 528. 639. 738.

50 110. 128. 183. 203. 286. 330. 383. 453. 551.

60 95.2 108. 140. 161. 228. 278. 309. 354. 455.

70 90.2 99.7 123. 134. 183. 216. 231. 271. 331.

75 87.8 96.8 112. 126. 164. 190. 202. 224. 273.

80 85.6 93.7 101. 110. 147. 168. 179. 188. 237.

90 77.2 79.0 87.6 92.2 120. 137. 145. 153. 172.

95 68.6 73.0 80.5 88.2 110. 118. 132. 142. 151.

98 60.7 66.0 77.5 86.2 105. 108. 120. 131. 133.

99 58.4 63.1 75.3 84.3 101. 104. 111. 124. 128.
Appendix 3 43

03125000 Home Creek near New Philadelphia, Ohio

Years analyzed = 42

Climatic year range = 1937–78

[APEE, annual percentage equaled or exceeded; ft3/s, cubic foot per second]

Daily mean streamflow (ft3/s) that was equaled or exceeded the indicated percentage of time at APEE level

APEE 95 90 80 70 50 30 20 10 5

1 8.67 8.86 9.34 11.3 15.3 18.8 21.5 25.1 30.4

2 4.88 5.62 6.92 7.50 9.84 12.4 12.7 15.6 18.0

5 2.49 3.14 3.27 3.73 5.14 6.10 6.85 7.53 8.17

10 1.52 1.71 1.94 2.23 2.99 3.37 3.78 4.06 5.08

20 0.71 0.82 1.08 1.12 1.55 1.90 1.99 2.27 2.82

25 0.51 0.60 0.70 0.89 1.27 1.56 1.64 1.87 2.16

30 0.32 0.40 0.53 0.64 0.93 1.23 1.45 1.58 1.86

40 0.12 0.21 0.30 0.36 0.55 0.90 0.98 1.17 1.29

50 0.05 0.10 0.14 0.20 0.30 0.60 0.71 0.83 0.87

60 0.00 0.01 0.08 0.10 0.20 0.36 0.47 0.60 0.65

70 0.00 0.00 0.02 0.06 0.10 0.20 0.27 0.39 0.45

75 0.00 0.00 0.00 0.03 0.10 0.14 0.20 0.30 0.40

80 0.00 0.00 0.00 0.02 0.07 0.10 0.12 0.25 0.32

90 0.00 0.00 0.00 0.00 0.02 0.04 0.07 0.10 0.15

95 0.00 0.00 0.00 0.00 0.00 0.02 0.05 0.09 0.10

98 0.00 0.00 0.00 0.00 0.00 0.01 0.04 0.06 0.10

99 0.00 0.00 0.00 0.00 0.00 0.01 0.02 0.04 0.06

7-day mean streamflow (ft3/s) that was equaled or exceeded the indicated percentage of time at APEE level

APEE 95 90 80 70 50 30 20 10 5

1 5.27 5.37 6.25 7.28 9.22 11.5 13.9 16.9 20.1

2 3.94 4.74 4.94 5.88 7.16 8.82 9.56 11.1 12.2

5 2.45 3.22 3.82 3.96 5.22 6.71 7.05 8.00 8.67

10 1.56 1.76 2.35 2.66 3.44 4.03 4.30 5.29 6.00

20 0.72 0.80 1.13 1.28 1.99 2.39 2.62 2.73 3.56

25 0.44 0.59 0.80 0.94 1.51 1.92 2.12 2.31 3.06

30 0.35 0.42 0.64 0.71 1.18 1.51 1.67 1.90 2.57

40 0.14 0.23 0.29 0.37 0.66 1.03 1.27 1.42 1.62

50 0.07 0.10 0.18 0.24 0.41 0.67 0.92 1.10 1.15

60 0.05 0.06 0.12 0.13 0.26 0.45 0.66 0.78 0.86

70 0.00 0.02 0.04 0.08 0.16 0.29 0.40 0.48 0.60

75 0.00 0.01 0.03 0.05 0.13 0.20 0.29 0.38 0.52

80 0.00 0.00 0.01 0.03 0.10 0.16 0.21 0.34 0.43

90 0.00 0.00 0.00 0.01 0.02 0.08 0.10 0.16 0.29

95 0.00 0.00 0.00 0.00 0.01 0.03 0.07 0.11 0.14

98 0.00 0.00 0.00 0.00 0.00 0.02 0.04 0.09 0.10

99 0.00 0.00 0.00 0.00 0.00 0.02 0.04 0.07 0.09
44 Methods for Estimating Selected Low-Flow Statistics and Development of Annual Flow-Duration Statistics for Ohio

03130500 Touby Run at Mansfield, Ohio

Years analyzed = 31

Climatic year range = 1947–77

[APEE, annual percentage equaled or exceeded; ft3/s, cubic foot per second]

Daily mean streamflow (ft3/s) that was equaled or exceeded the indicated percentage of time at APEE level

APEE 95 90 80 70 50 30 20 10 5

1 28.9 30.7 41.5 52.8 64.3 80.6 85.1 106. 139.

2 21.2 24.5 29.5 32.5 42.7 49.5 54.4 58.2 66.5

5 10.2 12.7 15.1 18.3 21.0 24.5 25.5 27.6 30.9

10 6.00 6.91 7.26 9.35 11.4 13.0 14.0 16.0 17.0

20 2.78 2.97 3.70 4.32 5.92 6.38 7.08 8.33 9.74

25 1.90 2.21 2.75 3.54 4.25 5.23 5.50 6.38 8.25

30 1.60 1.76 1.94 2.50 3.40 4.05 4.40 4.93 7.10

40 0.86 1.00 1.34 1.72 2.20 2.60 2.91 3.46 5.20

50 0.52 0.62 0.94 1.20 1.60 1.90 2.18 2.58 3.64

60 0.36 0.50 0.75 0.96 1.10 1.34 1.60 2.00 2.20

70 0.26 0.30 0.52 0.70 0.93 1.00 1.29 1.50 1.64

75 0.20 0.30 0.44 0.60 0.79 1.00 1.06 1.30 1.48

80 0.20 0.22 0.33 0.50 0.71 0.80 0.92 1.02 1.34

90 0.16 0.20 0.22 0.30 0.50 0.61 0.64 0.79 0.97

95 0.10 0.14 0.20 0.22 0.40 0.50 0.58 0.62 0.74

98 0.08 0.10 0.15 0.20 0.30 0.40 0.50 0.50 0.74

99 0.06 0.10 0.10 0.12 0.30 0.36 0.48 0.50 0.61

7-day mean streamflow (ft3/s) that was equaled or exceeded the indicated percentage of time at APEE level

APEE 95 90 80 70 50 30 20 10 5

1 19.0 25.2 29.7 30.5 33.4 41.3 44.7 62.1 68.4

2 13.1 16.1 21.5 23.0 25.8 32.1 35.9 40.7 47.9

5 9.54 10.5 14.9 17.1 18.8 20.9 24.2 31.2 35.5

10 6.53 6.67 9.41 11.7 13.8 14.6 17.0 17.8 19.2

20 3.17 3.53 5.09 5.56 7.40 9.30 10.6 12.8 13.0

25 2.47 3.00 3.48 4.31 6.07 6.72 7.60 9.71 11.5

30 1.84 2.08 2.83 3.36 4.89 5.48 6.02 7.52 9.50

40 1.01 1.20 1.75 2.33 2.94 3.93 4.23 4.67 6.89

50 0.61 0.81 1.16 1.61 2.07 2.80 3.21 3.61 5.00

60 0.44 0.55 0.94 1.25 1.47 2.16 2.43 2.83 3.63

70 0.33 0.39 0.66 0.87 1.23 1.58 1.80 2.30 2.45

75 0.27 0.33 0.50 0.77 1.04 1.31 1.51 1.88 2.19

80 0.23 0.27 0.45 0.63 0.90 1.18 1.34 1.56 1.75

90 0.20 0.21 0.30 0.50 0.74 0.82 0.88 1.02 1.16

95 0.16 0.20 0.20 0.34 0.47 0.64 0.68 0.80 0.96

98 0.13 0.15 0.18 0.26 0.40 0.53 0.58 0.68 0.87

99 0.10 0.11 0.16 0.23 0.36 0.49 0.52 0.58 0.79
Appendix 3 45

03134000 Jerome Fork at Jeromeville, Ohio

Years analyzed = 23

Climatic year range = 1926–48

[APEE, annual percentage equaled or exceeded; ft3/s, cubic foot per second]

Daily mean streamflow (ft3/s) that was equaled or exceeded the indicated percentage of time at APEE level

APEE 95 90 80 70 50 30 20 10 5

1 371. 664. 889. 947. 1290. 1600. 1940. 2270. 2440.

2 293. 467. 526. 736. 916. 1130. 1310. 1430. 1650.

5 127. 190. 310. 369. 420. 520. 580. 788. 901.

10 71.8 98.4 148. 169. 203. 260. 288. 398. 479.

20 39.4 43.9 60.2 67.5 95.2 130. 149. 197. 237.

25 26.8 32.4 43.1 51.0 70.0 106. 114. 162. 195.

30 16.8 24.2 30.8 37.6 55.0 86.8 91.8 127. 167.

40 10.1 13.8 18.5 21.6 34.6 58.6 69.0 81.5 106.

50 7.84 10.2 12.0 15.2 25.0 40.8 46.0 60.2 79.4

60 6.30 7.66 8.88 11.6 19.0 25.8 33.1 39.5 51.0

70 4.98 5.90 6.98 9.44 15.0 18.0 23.8 28.1 30.4

75 4.88 5.31 6.00 7.52 12.0 15.6 18.0 22.6 23.4

80 4.46 4.80 5.59 6.36 11.0 12.8 15.4 19.6 20.0

90 3.30 3.74 4.08 5.16 6.20 8.80 9.49 10.6 14.2

95 2.91 3.16 3.50 3.84 5.00 6.04 7.16 9.60 11.6

98 2.27 2.46 2.85 3.12 4.00 5.52 6.26 8.24 9.95

99 2.04 2.28 2.65 2.91 4.00 4.96 6.16 7.92 9.57

7-day mean streamflow (ft3/s) that was equaled or exceeded the indicated percentage of time at APEE level

APEE 95 90 80 70 50 30 20 10 5

1 242. 400. 558. 646. 733. 917. 1000. 1260. 1370.

2 193. 314. 433. 536. 657. 780. 886. 1100. 1250.

5 121. 212. 304. 377. 423. 615. 667. 709. 767.

10 82.9 126. 188. 226. 259. 312. 339. 421. 486.

20 41.1 50.1 64.8 80.2 134. 165. 198. 248. 298.

25 30.6 32.7 49.3 61.5 96.3 137. 161. 218. 243.

30 22.0 26.2 39.2 45.9 68.4 109. 129. 180. 212.

40 10.6 15.0 20.0 27.3 43.3 76.7 86.7 106. 141.

50 8.32 10.3 14.5 19.0 28.9 50.2 58.9 69.9 103.

60 6.97 8.40 9.27 12.1 23.4 32.3 43.8 49.2 71.3

70 5.87 6.70 7.76 9.99 17.7 22.2 24.8 35.3 40.2

75 5.29 5.73 6.80 8.77 14.1 17.0 21.0 29.1 29.7

80 4.89 5.09 6.12 7.75 12.9 14.0 17.0 22.2 25.4

90 3.91 4.26 4.45 5.46 7.30 9.85 11.4 12.6 15.3

95 3.40 3.59 3.95 4.86 5.70 7.64 8.79 10.9 13.7

98 2.80 3.08 3.21 3.38 4.49 5.79 7.41 10.1 11.8

99 2.57 2.71 2.95 3.24 4.00 5.51 6.75 9.65 11.0
46 Methods for Estimating Selected Low-Flow Statistics and Development of Annual Flow-Duration Statistics for Ohio

03136500 Kokosing River at Mount Vernon, Ohio

Years analyzed = 57

Climatic year range = 1953–2009

[APEE, annual percentage equaled or exceeded; ft3/s, cubic foot per second]

Daily mean streamflow (ft3/s) that was equaled or exceeded the indicated percentage of time at APEE level

APEE 98 95 90 80 50 20 10 5 2

1 821. 946. 1110. 1380. 1840. 2590. 2870. 3220. 3680.

2 562. 745. 839. 945. 1330. 1710. 1910. 1990. 2350.

5 306. 414. 448. 536. 757. 1070. 1120. 1310. 1550.

10 180. 223. 301. 328. 463. 652. 745. 837. 1040.

20 80.0 118. 168. 198. 275. 371. 418. 446. 499.

25 63.2 97.1 124. 164. 221. 305. 337. 367. 406.

30 49.8 75.2 104. 126. 188. 260. 300. 315. 356.

40 37.8 54.2 61.6 89.6 143. 185. 235. 255. 283.

50 30.8 39.5 45.6 64.6 110. 145. 188. 215. 234.

60 27.0 31.5 38.2 48.8 78.6 109. 149. 169. 180.

70 24.0 26.7 29.0 38.2 58.0 83.1 111. 129. 146.

75 21.3 23.0 27.0 32.8 50.0 76.2 99.8 111. 134.

80 20.2 21.9 24.4 30.0 44.2 69.8 86.9 91.2 121.

90 15.3 18.8 20.8 25.6 35.0 56.0 62.4 71.3 85.6

95 13.4 14.3 18.4 23.2 32.0 49.6 52.5 59.0 70.3

98 11.4 12.3 16.4 20.0 28.3 42.7 47.3 49.3 58.9

99 10.6 10.7 14.8 18.0 27.7 40.2 46.2 48.0 56.9

7-day mean streamflow (ft3/s) that was equaled or exceeded the indicated percentage of time at APEE level

APEE 98 95 90 80 50 20 10 5 2

1 414. 616. 678. 871. 1370. 1670. 1970. 2560. 3450.

2 378. 523. 603. 760. 991. 1370. 1530. 1620. 2170.

5 287. 397. 449. 553. 735. 953. 1060. 1180. 1180.

10 199. 221. 326. 374. 494. 667. 723. 799. 898.

20 74.5 130. 158. 222. 313. 439. 481. 574. 599.

25 63.6 107. 124. 170. 253. 370. 435. 489. 509.

30 53.9 85.1 111. 138. 216. 304. 364. 403. 454.

40 38.3 56.1 62.5 94.5 159. 219. 274. 292. 353.

50 31.6 39.2 47.7 65.7 117. 164. 210. 242. 284.

60 27.3 32.4 36.5 49.1 83.1 121. 161. 206. 216.

70 22.7 27.9 30.0 37.7 60.3 90.8 124. 145. 156.

75 21.5 23.3 27.4 34.0 53.6 79.5 106. 121. 142.

80 20.5 22.0 25.4 30.8 47.0 74.6 93.8 99.9 136.

90 16.1 19.2 21.0 26.4 36.7 59.4 68.1 77.5 91.2

95 14.0 14.7 18.4 24.7 33.0 51.9 56.6 64.2 78.3

98 11.8 13.3 17.0 20.7 31.0 45.7 50.1 53.5 67.3

99 10.9 12.7 15.7 19.1 29.6 42.9 48.6 51.0 63.5
Appendix 3 47

03137000 Kokosing River at Millwood, Ohio

Years analyzed = 52

Climatic year range = 1922–73

[APEE, annual percentage equaled or exceeded; ft3/s, cubic foot per second]

Daily mean streamflow (ft3/s) that was equaled or exceeded the indicated percentage of time at APEE level

APEE 98 95 90 80 50 20 10 5 2

1 696. 1410. 2370. 3020. 4500. 6160. 6960. 7710. 9070.

2 572. 825. 1780. 2280. 2840. 3920. 4700. 5180. 5310.

5 383. 523. 943. 1290. 1740. 2210. 2750. 2850. 2940.

10 245. 373. 545. 735. 1080. 1360. 1570. 1730. 1850.

20 141. 203. 287. 419. 619. 750. 952. 1040. 1160.

25 128. 146. 235. 322. 502. 641. 802. 886. 1000.

30 108. 112. 189. 251. 418. 553. 676. 787. 798.

40 72.2 88.4 117. 159. 278. 404. 467. 609. 638.

50 64.0 69.2 86.0 114. 199. 298. 345. 442. 498.

60 55.1 59.0 70.0 92.4 152. 213. 278. 332. 400.

70 51.1 53.3 62.8 78.3 117. 160. 209. 247. 319.

75 49.1 51.0 60.5 72.6 97.8 136. 181. 210. 292.

80 46.0 48.7 54.7 65.2 86.9 120. 157. 177. 259.

90 42.0 43.5 45.3 58.6 75.0 96.9 122. 137. 173.

95 38.1 39.6 42.2 54.4 70.0 85.4 107. 122. 154.

98 36.0 36.8 39.0 46.2 64.8 80.8 94.6 113. 130.

99 35.1 36.0 38.3 45.2 62.0 77.9 92.2 110. 128.

7-day mean streamflow (ft3/s) that was equaled or exceeded the indicated percentage of time at APEE level

APEE 98 95 90 80 50 20 10 5 2

1 504. 868. 1550. 2230. 2840. 4220. 5570. 6350. 8980.

2 453. 716. 1310. 1970. 2330. 3050. 3860. 4760. 4900.

5 362. 485. 1120. 1290. 1710. 2170. 2570. 2710. 2920.

10 249. 398. 534. 860. 1160. 1450. 1730. 1890. 1940.

20 142. 186. 292. 449. 700. 938. 1090. 1240. 1270.

25 121. 149. 237. 364. 578. 739. 869. 1050. 1140.

30 108. 116. 194. 251. 472. 645. 741. 911. 1050.

40 76.2 88.1 123. 167. 327. 462. 571. 678. 722.

50 63.9 70.4 93.7 119. 222. 347. 389. 493. 581.

60 57.1 59.2 71.7 94.6 160. 237. 314. 389. 469.

70 51.3 54.2 63.7 81.6 126. 176. 238. 272. 338.

75 50.0 51.0 61.3 73.1 103. 150. 190. 222. 309.

80 48.0 49.1 56.5 65.5 93.4 128. 165. 191. 283.

90 40.6 43.9 48.2 59.5 77.4 100. 130. 143. 190.

95 37.9 40.6 44.6 55.3 73.4 89.1 111. 127. 169.

98 37.3 38.0 42.9 48.7 67.5 82.9 99.1 121. 142.

99 37.0 37.2 41.6 46.4 65.3 80.4 96.5 117. 133.
48 Methods for Estimating Selected Low-Flow Statistics and Development of Annual Flow-Duration Statistics for Ohio

03139000 Killbuck Creek at Killbuck, Ohio

Years analyzed = 78

Climatic year range = 1931–2008

[APEE, annual percentage equaled or exceeded; ft3/s, cubic foot per second]

Daily mean streamflow (ft3/s) that was equaled or exceeded the indicated percentage of time at APEE level

APEE 98 95 90 80 50 20 10 5 2

1 1260. 1340. 1630. 2000. 2530. 3460. 4200. 4850. 9010.

2 1010. 1150. 1440. 1620. 2100. 2780. 3140. 3340. 3970.

5 660. 783. 913. 1110. 1470. 1920. 2220. 2520. 2630.

10 472. 501. 569. 707. 1020. 1390. 1510. 1690. 1800.

20 218. 287. 320. 402. 588. 879. 1040. 1170. 1230.

25 157. 216. 238. 320. 489. 713. 937. 992. 1050.

30 119. 178. 205. 274. 409. 585. 769. 832. 928.

40 81.9 96.5 133. 177. 305. 443. 511. 632. 676.

50 59.0 71.8 94.5 115. 221. 315. 385. 501. 558.

60 47.3 61.4 76.8 89.7 158. 231. 315. 405. 458.

70 39.7 51.8 58.6 71.0 121. 179. 266. 317. 375.

75 35.9 46.8 51.0 65.3 103. 154. 229. 277. 352.

80 33.7 43.1 46.9 60.2 92.2 134. 193. 257. 316.

90 29.2 31.0 38.9 47.8 74.0 104. 135. 197. 256.

95 26.6 30.0 36.9 43.3 63.6 93.1 120. 157. 231.

98 24.3 28.0 33.3 38.0 57.0 81.8 99.4 144. 176.

99 24.2 26.6 32.0 36.6 56.0 79.3 96.4 135. 149.

7-day mean streamflow (ft3/s) that was equaled or exceeded the indicated percentage of time at APEE level

APEE 98 95 90 80 50 20 10 5 2

1 983. 1020. 1350. 1700. 2160. 2920. 3640. 4930. 9130.

2 824. 962. 1190. 1470. 1820. 2480. 2800. 3960. 5540.

5 585. 710. 862. 1030. 1390. 1820. 2110. 2280. 2450.

10 443. 503. 538. 709. 991. 1330. 1530. 1620. 1730.

20 216. 292. 319. 404. 616. 896. 1040. 1110. 1220.

25 156. 228. 256. 341. 523. 785. 901. 984. 1070.

30 134. 189. 213. 282. 442. 645. 796. 857. 915.

40 83.3 102. 138. 176. 329. 475. 575. 690. 748.

50 60.4 81.6 103. 126. 238. 338. 412. 559. 618.

60 48.4 65.3 78.3 95.8 166. 253. 342. 432. 521.

70 40.1 55.2 60.3 76.3 131. 188. 286. 343. 412.

75 36.5 47.2 54.4 67.0 109. 165. 247. 308. 380.

80 33.8 43.6 49.6 62.6 93.7 147. 206. 269. 346.

90 29.5 33.5 41.3 51.2 75.8 114. 143. 214. 293.

95 26.7 30.4 37.1 44.7 67.6 96.6 124. 183. 261.

98 25.2 29.1 35.2 40.5 57.8 89.9 111. 163. 211.

99 24.7 27.4 34.3 38.7 57.3 88.0 102. 150. 176.
Appendix 3 49

03140000 Mill Creek near Coshocton, Ohio

Years analyzed = 72

Climatic year range = 1937–2008

[APEE, annual percentage equaled or exceeded; ft3/s, cubic foot per second]

Daily mean streamflow (ft3/s) that was equaled or exceeded the indicated percentage of time at APEE level

APEE 98 95 90 80 50 20 10 5 2

1 130. 144. 165. 193. 291. 408. 462. 478. 571.

2 64.9 92.2 101. 128. 184. 255. 283. 345. 408.

5 38.9 49.3 55.8 71.2 97.3 136. 152. 160. 212.

10 26.1 32.7 39.0 44.9 61.0 83.7 93.6 99.1 119.

20 14.5 16.5 19.6 25.5 37.1 48.0 53.2 56.4 64.1

25 9.39 11.8 14.2 19.3 30.8 39.7 44.7 49.7 52.6

30 6.79 7.78 11.0 14.6 25.1 32.5 38.1 40.3 44.5

40 3.00 3.67 6.45 9.33 16.3 24.0 27.9 31.1 34.9

50 1.84 2.15 3.32 5.00 10.8 18.4 20.7 24.0 28.2

60 1.00 1.28 2.10 3.16 7.00 12.4 15.7 17.7 22.9

70 0.55 0.83 1.22 1.78 4.28 7.78 10.0 13.3 18.2

75 0.30 0.61 0.80 1.40 3.10 6.05 8.32 11.7 16.6

80 0.25 0.44 0.60 1.20 2.20 4.89 7.11 10.2 13.6

90 0.10 0.20 0.30 0.56 1.25 2.70 4.57 6.84 10.0

95 0.10 0.10 0.15 0.30 1.00 2.03 3.11 5.48 8.80

98 0.10 0.10 0.11 0.20 0.62 1.64 2.43 4.35 7.84

99 0.08 0.10 0.10 0.20 0.51 1.51 2.05 4.10 7.16

7-day mean streamflow (ft3/s) that was equaled or exceeded the indicated percentage of time at APEE level

APEE 98 95 90 80 50 20 10 5 2

1 72.2 93.7 102. 119. 171. 230. 306. 402. 460.

2 63.1 78.6 90.1 101. 143. 190. 222. 256. 289.

5 37.2 49.4 65.7 76.5 103. 137. 150. 168. 212.

10 25.7 36.3 41.5 49.9 69.0 93.8 101. 114. 134.

20 13.4 18.7 21.4 27.2 42.6 57.3 67.5 71.4 77.3

25 9.49 12.3 16.3 21.7 34.7 48.1 55.4 60.8 67.3

30 7.27 8.11 12.1 16.1 29.2 38.2 44.9 49.7 61.2

40 3.36 3.92 7.12 10.6 18.9 28.3 33.6 38.6 44.9

50 2.27 2.52 4.35 5.73 11.6 20.4 24.3 27.4 36.1

60 1.30 1.44 2.55 3.90 7.42 14.8 18.1 20.4 28.6

70 0.61 0.98 1.58 2.22 4.68 9.27 12.2 16.4 22.1

75 0.33 0.71 1.04 1.65 3.69 6.97 10.0 13.8 19.8

80 0.21 0.52 0.76 1.32 2.73 5.65 8.02 11.7 17.6

90 0.11 0.27 0.36 0.70 1.59 3.31 5.73 8.34 12.4

95 0.10 0.14 0.22 0.38 1.14 2.43 4.19 6.41 10.1

98 0.10 0.10 0.14 0.26 0.81 1.91 3.02 5.22 9.35

99 0.08 0.10 0.11 0.22 0.62 1.70 2.72 4.91 8.91
50 Methods for Estimating Selected Low-Flow Statistics and Development of Annual Flow-Duration Statistics for Ohio

03144000 Wakatomika Creek near Frazeysburg, Ohio

Years analyzed = 72

Climatic year range = 1937–2008

[APEE, annual percentage equaled or exceeded; ft3/s, cubic foot per second]

Daily mean streamflow (ft3/s) that was equaled or exceeded the indicated percentage of time at APEE level

APEE 98 95 90 80 50 20 10 5 2

1 577. 813. 944. 1070. 1430. 2020. 2590. 3190. 3250.

2 374. 511. 575. 764. 974. 1250. 1480. 1870. 2070.

5 218. 269. 355. 400. 540. 680. 761. 849. 1090.

10 137. 174. 203. 256. 332. 435. 478. 531. 649.

20 57.8 91.7 119. 151. 194. 253. 297. 319. 357.

25 36.3 72.4 95.6 119. 161. 213. 244. 261. 284.

30 27.2 53.1 72.0 95.3 134. 179. 206. 218. 248.

40 18.7 27.9 45.4 63.5 96.1 131. 151. 163. 188.

50 12.9 17.6 23.6 42.2 65.0 96.4 111. 134. 151.

60 9.52 13.7 15.0 25.0 46.0 65.0 78.0 106. 122.

70 7.95 9.93 11.2 17.5 30.3 47.9 59.1 75.5 96.2

75 7.09 8.71 10.3 14.0 25.0 38.9 47.4 63.0 87.0

80 6.31 7.45 9.21 11.0 20.0 31.5 40.7 53.8 73.2

90 4.49 5.30 6.24 8.06 12.8 21.8 28.0 34.2 51.9

95 3.44 4.16 4.80 6.93 9.45 15.9 21.8 27.4 37.4

98 2.84 3.37 4.16 5.61 8.32 13.8 18.7 23.4 31.0

99 2.75 3.20 3.69 5.35 8.00 12.8 17.9 21.6 29.1

7-day mean streamflow (ft3/s) that was equaled or exceeded the indicated percentage of time at APEE level

APEE 98 95 90 80 50 20 10 5 2

1 381. 537. 600. 721. 1020. 1480. 1910. 2040. 2890.

2 324. 462. 509. 573. 772. 1040. 1180. 1380. 1610.

5 241. 299. 324. 423. 548. 705. 829. 970. 1070.

10 143. 184. 219. 294. 371. 477. 549. 574. 707.

20 50.2 95.2 119. 160. 225. 291. 343. 348. 409.

25 38.2 69.1 102. 129. 179. 243. 288. 301. 372.

30 25.2 57.9 73.3 109. 153. 199. 240. 259. 322.

40 18.6 27.3 46.4 66.8 107. 149. 175. 189. 247.

50 13.3 17.9 25.8 44.1 74.1 107. 133. 145. 194.

60 10.2 14.3 16.0 28.6 50.5 74.0 93.4 117. 148.

70 8.24 10.4 12.1 18.6 33.6 51.6 68.2 81.9 113.

75 7.13 8.81 10.8 15.6 26.9 44.4 52.6 70.1 102.

80 6.53 7.93 9.54 12.5 22.1 35.6 45.1 58.0 88.2

90 4.51 5.52 7.42 8.54 13.6 23.5 30.7 38.4 61.2

95 3.50 4.33 5.33 7.38 10.6 18.2 24.1 32.2 44.2

98 2.95 3.69 4.40 6.18 9.26 14.9 20.7 25.3 36.0

99 2.83 3.47 3.97 5.69 8.71 13.8 19.4 24.3 32.2
Appendix 3 51

03146000 North Fork Licking River at Utica, Ohio

Years analyzed = 20

Climatic year range = 1940–81

[APEE, annual percentage equaled or exceeded; ft3/s, cubic foot per second]

Daily mean streamflow (ft3/s) that was equaled or exceeded the indicated percentage of time at APEE level

APEE 95 90 80 70 50 30 20 10 5

1 814. 904. 1430. 1540. 1820. 2260. 2510. 2950. 2990.

2 573. 753. 863. 993. 1270. 1440. 1710. 1770. 1780.

5 290. 313. 428. 500. 560. 778. 820. 852. 863.

10 142. 172. 198. 238. 292. 402. 455. 482. 506.

20 68.0 73.5 95.0 120. 148. 194. 221. 234. 263.

25 45.7 58.6 70.5 96.8 111. 150. 169. 179. 201.

30 25.4 44.6 54.6 75.6 90.5 119. 135. 153. 174.

40 8.91 30.1 34.5 50.9 61.6 82.0 89.7 111. 127.

50 6.08 19.3 24.2 33.6 45.5 53.9 63.7 81.8 84.8

60 4.25 7.38 16.4 21.2 29.5 37.0 44.7 62.0 62.0

70 3.55 4.77 10.8 14.0 17.4 27.7 30.6 42.7 51.6

75 3.43 4.23 8.28 10.6 13.5 22.5 24.0 31.3 45.3

80 3.04 3.98 7.16 8.73 12.0 15.8 19.8 20.2 37.5

90 1.86 3.04 4.65 6.09 7.14 9.77 11.8 14.9 25.2

95 1.48 2.46 3.79 4.83 5.42 8.28 9.58 11.2 20.5

98 1.06 2.24 3.46 3.86 4.34 5.92 7.44 8.92 15.0

99 0.95 1.92 3.01 3.18 3.85 5.44 6.59 7.44 13.7

7-day mean streamflow (ft3/s) that was equaled or exceeded the indicated percentage of time at APEE level

APEE 95 90 80 70 50 30 20 10 5

1 556. 596. 696. 773. 967. 1200. 1350. 1430. 1490.

2 426. 495. 633. 670. 765. 970. 1040. 1130. 1280.

5 248. 323. 416. 448. 536. 679. 767. 826. 894.

10 163. 244. 294. 304. 362. 496. 528. 554. 559.

20 87.7 94.1 132. 175. 201. 273. 288. 365. 408.

25 58.7 74.5 87.6 138. 170. 204. 236. 276. 330.

30 25.8 56.1 71.6 103. 123. 172. 196. 208. 286.

40 9.70 33.9 42.4 61.8 82.4 107. 129. 139. 166.

50 6.30 21.6 29.8 41.3 55.9 70.3 91.3 107. 108.

60 4.21 8.00 18.5 26.0 37.5 43.6 63.6 75.1 80.4

70 3.51 4.79 11.1 16.2 19.6 32.8 40.8 48.4 64.9

75 3.31 4.07 8.98 12.8 15.0 26.4 30.0 37.1 58.1

80 2.99 3.87 7.67 9.79 13.1 19.3 22.9 27.9 53.0

90 2.12 3.17 5.20 6.29 7.61 11.1 13.0 15.7 30.9

95 1.86 2.71 4.32 5.11 5.91 8.86 10.2 12.3 24.4

98 1.47 2.50 3.59 4.48 5.31 7.88 8.93 9.58 18.3

99 1.34 2.42 3.19 4.00 4.62 6.88 7.49 8.59 16.0
52 Methods for Estimating Selected Low-Flow Statistics and Development of Annual Flow-Duration Statistics for Ohio

03146500 Licking River near Newark, Ohio

Years analyzed = 67

Climatic year range = 1940–2008

[APEE, annual percentage equaled or exceeded; ft3/s, cubic foot per second]

Daily mean streamflow (ft3/s) that was equaled or exceeded the indicated percentage of time at APEE level

APEE 98 95 90 80 50 20 10 5 2

1 2110. 2990. 3540. 4240. 5570. 6960. 8070. 9230. 10100.

2 1330. 1930. 2480. 2880. 3890. 5180. 5500. 5920. 7520.

5 725. 935. 1300. 1620. 2310. 2980. 3360. 3540. 4700.

10 435. 547. 775. 950. 1450. 1850. 2090. 2240. 2880.

20 194. 306. 384. 525. 755. 1060. 1210. 1310. 1650.

25 161. 234. 301. 418. 631. 889. 990. 1110. 1420.

30 131. 191. 245. 337. 530. 768. 843. 943. 1280.

40 82.7 123. 155. 234. 375. 532. 636. 707. 953.

50 64.8 90.0 108. 168. 271. 388. 501. 564. 745.

60 54.0 62.9 85.0 128. 191. 282. 359. 454. 578.

70 45.1 53.0 72.4 93.5 141. 197. 271. 314. 433.

75 42.4 50.4 67.2 78.6 120. 172. 224. 262. 373.

80 42.1 46.8 59.9 70.8 100. 149. 179. 227. 336.

90 40.0 44.2 53.3 60.8 78.0 114. 135. 168. 248.

95 36.7 40.0 51.0 54.3 68.0 99.4 116. 141. 195.

98 33.3 38.6 48.3 52.0 63.0 91.0 102. 125. 176.

99 31.8 37.2 45.5 49.9 61.0 88.0 99.2 118. 171.

7-day mean streamflow (ft3/s) that was equaled or exceeded the indicated percentage of time at APEE level

APEE 98 95 90 80 50 20 10 5 2

1 1120. 1770. 2240. 2660. 3540. 5130. 6270. 6720. 7260.

2 970. 1600. 1920. 2250. 2950. 3940. 4350. 4510. 4950.

5 690. 1080. 1330. 1720. 2190. 2690. 3150. 3450. 4020.

10 472. 576. 866. 1130. 1530. 1920. 2040. 2310. 2880.

20 209. 325. 419. 593. 928. 1250. 1440. 1590. 1980.

25 171. 260. 331. 444. 736. 1050. 1190. 1400. 1750.

30 131. 217. 254. 389. 623. 927. 1010. 1150. 1490.

40 83.2 133. 154. 251. 422. 644. 777. 838. 1170.

50 64.4 97.2 111. 177. 303. 483. 559. 657. 939.

60 53.4 62.5 90.3 138. 216. 349. 421. 528. 683.

70 45.9 54.8 77.3 98.4 153. 233. 310. 377. 496.

75 43.5 51.7 68.9 88.2 125. 193. 252. 321. 439.

80 41.9 48.8 63.3 75.1 109. 173. 214. 254. 396.

90 39.6 45.5 53.6 61.8 81.9 121. 144. 193. 291.

95 37.9 41.2 52.0 56.8 69.3 101. 123. 154. 214.

98 34.9 39.7 49.3 54.5 65.7 93.6 111. 131. 181.

99 33.6 38.6 48.4 52.9 63.0 91.7 105. 125. 178.
Appendix 3 53

03147000 Licking River at Toboso, Ohio

Years analyzed = 41

Climatic year range = 1904–60

[APEE, annual percentage equaled or exceeded; ft3/s, cubic foot per second]

Daily mean streamflow (ft3/s) that was equaled or exceeded the indicated percentage of time at APEE level

APEE 95 90 80 70 50 30 20 10 5

1 1950. 2890. 4980. 5420. 6420. 7470. 8260. 9850. 11500.

2 1000. 2120. 3340. 3660. 4600. 5510. 6200. 6900. 7890.

5 605. 1270. 1930. 2030. 2580. 3170. 3460. 3850. 4020.

10 371. 819. 1130. 1270. 1510. 1800. 2050. 2190. 2390.

20 250. 453. 541. 693. 834. 1000. 1110. 1270. 1430.

25 191. 356. 437. 516. 665. 827. 932. 1050. 1170.

30 150. 279. 350. 385. 560. 687. 784. 897. 958.

40 107. 158. 234. 270. 402. 511. 576. 613. 675.

50 82.5 111. 153. 193. 299. 345. 387. 451. 505.

60 69.3 80.2 116. 134. 224. 261. 300. 322. 343.

70 59.8 69.4 96.0 105. 162. 191. 207. 223. 248.

75 56.8 66.4 89.4 95.9 138. 159. 178. 199. 208.

80 55.7 64.4 81.0 87.2 115. 135. 145. 169. 177.

90 52.4 59.0 68.0 75.3 92.0 102. 108. 128. 146.

95 50.2 53.0 61.2 70.2 81.5 90.2 99.2 112. 138.

98 47.7 48.7 54.8 66.4 73.0 82.8 95.6 104. 119.

99 46.0 47.0 53.3 63.5 70.0 80.4 93.0 99.3 116.

7-day mean streamflow (ft3/s) that was equaled or exceeded the indicated percentage of time at APEE level

APEE 95 90 80 70 50 30 20 10 5

1 1060. 2320. 2810. 3150. 4360. 5390. 6010. 7760. 9260.

2 848. 1910. 2330. 2620. 3220. 4200. 4510. 5260. 5750.

5 707. 1230. 1920. 2080. 2320. 3010. 3160. 3470. 4080.

10 392. 827. 1260. 1450. 1750. 2090. 2300. 2370. 2520.

20 277. 492. 644. 819. 1020. 1260. 1390. 1490. 1620.

25 233. 403. 508. 634. 809. 971. 1100. 1280. 1330.

30 181. 301. 399. 446. 666. 770. 913. 1100. 1170.

40 111. 170. 226. 280. 459. 561. 636. 725. 829.

50 88.1 118. 167. 199. 326. 407. 449. 504. 566.

60 68.7 82.3 120. 150. 247. 293. 340. 365. 412.

70 59.4 71.6 101. 111. 173. 219. 241. 267. 279.

75 57.4 67.9 95.1 100. 143. 173. 200. 229. 234.

80 55.8 66.0 86.4 92.0 119. 148. 159. 194. 208.

90 53.5 60.8 70.7 76.7 95.6 105. 111. 135. 154.

95 50.5 57.7 63.5 71.4 83.6 94.8 100. 119. 138.

98 48.8 50.3 58.3 70.5 78.6 88.3 97.4 113. 128.

99 48.1 48.5 57.0 68.9 73.0 85.6 96.2 112. 122.
54 Methods for Estimating Selected Low-Flow Statistics and Development of Annual Flow-Duration Statistics for Ohio

03157000 Clear Creek near Rockbridge, Ohio

Years analyzed = 69

Climatic year range = 1940–2008

[APEE, annual percentage equaled or exceeded; ft3/s, cubic foot per second]

Daily mean streamflow (ft3/s) that was equaled or exceeded the indicated percentage of time at APEE level

APEE 98 95 90 80 50 20 10 5 2

1 215. 345. 518. 580. 768. 1100. 1400. 1560. 1720.

2 152. 248. 313. 375. 523. 733. 857. 1030. 1140.

5 90.6 135. 167. 210. 300. 402. 442. 508. 556.

10 67.2 93.7 105. 125. 170. 243. 273. 300. 377.

20 47.4 57.0 68.0 75.2 102. 144. 163. 189. 222.

25 41.0 47.5 56.3 63.5 88.5 125. 140. 159. 176.

30 32.8 38.0 47.9 55.2 76.2 105. 122. 136. 154.

40 21.4 27.0 33.6 43.0 58.0 81.0 97.0 107. 122.

50 18.8 21.3 25.0 34.0 44.0 66.0 76.0 87.0 97.2

60 16.0 17.0 19.0 25.0 33.0 48.4 68.0 71.2 81.0

70 13.4 15.0 16.0 19.0 27.0 36.0 46.0 59.0 68.6

75 13.0 14.0 15.0 18.0 24.0 31.0 42.0 53.5 61.7

80 12.0 13.0 14.0 17.0 22.0 28.0 38.0 48.3 55.6

90 9.40 11.0 11.0 13.0 17.0 21.6 30.0 38.5 45.0

95 8.21 9.70 11.0 12.0 16.0 20.0 27.0 32.6 38.6

98 7.40 8.10 9.80 11.0 14.3 19.0 25.0 28.0 33.7

99 5.98 7.70 9.20 10.0 14.0 18.0 22.0 25.8 32.1

7-day mean streamflow (ft3/s) that was equaled or exceeded the indicated percentage of time at APEE level

APEE 98 95 90 80 50 20 10 5 2

1 159. 237. 288. 365. 513. 739. 980. 1050. 1400.

2 136. 192. 260. 287. 412. 548. 631. 838. 1020.

5 101. 137. 169. 221. 292. 395. 461. 491. 608.

10 66.5 91.5 108. 138. 200. 268. 313. 335. 372.

20 49.4 59.9 69.7 80.9 119. 170. 189. 219. 246.

25 44.4 49.3 59.9 69.3 97.3 149. 160. 189. 225.

30 36.0 40.2 49.6 62.1 84.0 125. 136. 157. 201.

40 21.2 28.3 36.3 46.7 63.7 90.3 110. 129. 152.

50 18.9 22.5 27.7 36.0 48.7 69.0 84.6 105. 119.

60 16.5 17.0 20.1 26.3 35.9 54.5 71.3 81.7 95.1

70 14.0 15.1 17.0 19.9 28.0 42.0 51.1 67.4 81.6

75 13.5 14.1 15.9 18.7 25.1 35.4 45.7 59.4 71.9

80 12.7 12.9 14.7 17.4 23.3 30.9 42.3 52.6 61.6

90 9.57 11.3 12.0 14.1 17.9 24.1 35.0 42.4 50.9

95 8.78 10.2 11.0 12.0 16.3 20.6 29.9 35.9 42.6

98 8.38 9.33 10.4 11.1 15.3 19.1 27.0 31.4 37.8

99 7.71 8.42 10.0 11.0 14.9 18.7 26.0 28.0 35.3
Appendix 3 55

03157500 Hocking River at Enterprise, Ohio

Years analyzed = 77

Climatic year range = 1932–2008

[APEE, annual percentage equaled or exceeded; ft3/s, cubic foot per second]

Daily mean streamflow (ft3/s) that was equaled or exceeded the indicated percentage of time at APEE level

APEE 98 95 90 80 50 20 10 5 2

1 1200. 1580. 2210. 2920. 3940. 5650. 6940. 7450. 8940.

2 752. 1210. 1770. 2100. 2800. 3780. 4800. 5570. 5890.

5 479. 763. 962. 1190. 1680. 2240. 2380. 3000. 3250.

10 345. 506. 571. 723. 1030. 1440. 1660. 1760. 1880.

20 221. 280. 326. 430. 586. 815. 958. 1030. 1200.

25 174. 231. 268. 342. 468. 661. 811. 856. 1020.

30 132. 179. 216. 278. 387. 563. 681. 743. 862.

40 87.2 118. 145. 193. 279. 430. 524. 589. 682.

50 66.0 85.7 103. 134. 209. 335. 416. 469. 550.

60 54.6 64.4 70.8 93.6 151. 255. 333. 381. 436.

70 46.5 52.8 58.4 70.5 116. 187. 258. 283. 352.

75 42.8 47.8 53.2 63.8 101. 161. 222. 249. 311.

80 39.8 42.9 47.0 57.7 88.4 135. 197. 218. 266.

90 32.0 35.5 39.8 48.5 68.0 97.8 129. 162. 203.

95 28.6 31.0 36.6 43.2 61.0 84.0 104. 139. 164.

98 28.6 29.3 32.0 38.3 55.3 77.4 97.2 120. 144.

99 27.4 28.3 30.9 37.6 50.0 71.3 92.7 118. 127.

7-day mean streamflow (ft3/s) that was equaled or exceeded the indicated percentage of time at APEE level

APEE 98 95 90 80 50 20 10 5 2

1 872. 1230. 1600. 2040. 2830. 3720. 5750. 6790. 7820.

2 750. 948. 1270. 1610. 2250. 3040. 3660. 4180. 5360.

5 439. 771. 927. 1060. 1560. 2060. 2430. 2580. 2750.

10 333. 491. 628. 769. 1090. 1450. 1630. 1880. 2050.

20 234. 265. 327. 463. 646. 930. 1080. 1160. 1280.

25 199. 224. 267. 361. 499. 795. 918. 946. 1130.

30 149. 184. 216. 306. 407. 660. 783. 830. 1030.

40 90.1 121. 162. 217. 305. 488. 591. 679. 833.

50 68.2 88.8 120. 146. 227. 382. 470. 537. 646.

60 56.9 70.2 78.5 104. 170. 304. 381. 449. 498.

70 46.5 55.0 63.3 77.1 126. 210. 290. 342. 431.

75 43.4 52.3 57.3 67.2 109. 175. 258. 285. 363.

80 40.5 47.5 51.6 60.5 94.7 155. 222. 248. 298.

90 32.6 37.6 43.8 52.1 73.1 109. 140. 185. 228.

95 29.4 34.5 37.6 45.2 64.4 95.3 118. 151. 187.

98 28.7 30.7 35.2 41.5 60.0 85.3 107. 128. 162.

99 28.2 29.8 31.7 38.4 56.7 80.0 102. 121. 144.
56 Methods for Estimating Selected Low-Flow Statistics and Development of Annual Flow-Duration Statistics for Ohio

03159540 Shade River near Chester, Ohio

Years analyzed = 42

Climatic year range = 1966–2008

[APEE, annual percentage equaled or exceeded; ft3/s, cubic foot per second]

Daily mean streamflow (ft3/s) that was equaled or exceeded the indicated percentage of time at APEE level

APEE 95 90 80 70 50 30 20 10 5

1 1100. 1220. 1530. 1780. 2060. 2380. 2560. 3380. 3530.

2 768. 801. 1130. 1330. 1530. 1680. 1710. 2080. 2230.

5 386. 443. 515. 597. 723. 893. 1010. 1100. 1240.

10 176. 228. 255. 306. 358. 434. 524. 596. 659.

20 93.6 112. 130. 147. 182. 230. 276. 307. 324.

25 77.9 81.5 98.8 116. 146. 187. 222. 252. 262.

30 58.5 66.0 74.8 93.3 109. 158. 177. 201. 231.

40 28.2 45.9 51.6 60.2 75.1 108. 127. 155. 161.

50 10.4 24.3 31.6 39.8 45.5 79.5 91.2 124. 132.

60 4.07 11.0 19.6 20.4 28.0 51.1 59.4 89.2 102.

70 1.42 5.80 8.32 9.36 18.0 30.5 41.2 67.8 81.7

75 1.23 4.09 5.64 7.56 13.9 26.0 30.2 49.8 67.6

80 0.95 3.27 4.06 5.11 11.0 17.3 23.2 32.3 57.4

90 0.53 1.30 1.84 2.44 5.46 9.33 13.0 20.1 36.6

95 0.37 0.72 1.17 1.69 3.26 6.75 9.16 14.8 28.1

98 0.26 0.41 0.85 1.21 1.93 4.94 6.56 10.0 22.2

99 0.21 0.35 0.72 0.90 1.58 4.20 5.87 7.95 14.4

7-day mean streamflow (ft3/s) that was equaled or exceeded the indicated percentage of time at APEE level

APEE 95 90 80 70 50 30 20 10 5

1 589. 598. 814. 945. 1060. 1350. 1560. 1990. 2600.

2 534. 563. 692. 800. 890. 1020. 1160. 1590. 1800.

5 403. 436. 542. 599. 690. 761. 833. 948. 993.

10 264. 286. 346. 392. 450. 527. 557. 642. 722.

20 114. 145. 172. 188. 264. 326. 352. 398. 463.

25 92.8 103. 122. 139. 196. 243. 304. 358. 368.

30 60.5 81.1 94.2 109. 138. 199. 264. 279. 331.

40 32.9 52.9 64.1 70.8 90.8 135. 177. 198. 225.

50 13.0 26.8 37.3 44.2 58.2 98.7 116. 156. 173.

60 5.26 13.1 23.9 27.6 33.8 64.0 75.1 122. 135.

70 1.54 7.86 11.4 12.3 22.9 42.6 54.6 92.0 111.

75 1.33 5.21 6.84 8.71 17.5 31.3 42.3 79.7 102.

80 1.15 3.76 4.64 6.95 13.6 23.4 31.3 52.4 86.0

90 0.64 1.49 2.11 2.72 6.80 12.5 19.0 26.4 49.5

95 0.38 0.79 1.27 1.77 4.85 9.05 12.1 19.8 37.2

98 0.31 0.51 0.97 1.37 2.78 6.97 8.51 14.0 28.1

99 0.27 0.44 0.89 1.16 2.10 5.57 7.70 9.91 24.2
Appendix 3 57

03202000 Raccoon Creek at Adamsville, Ohio

Years analyzed = 82

Climatic year range = 1916–2008

[APEE, annual percentage equaled or exceeded; ft3/s, cubic foot per second]

Daily mean streamflow (ft3/s) that was equaled or exceeded the indicated percentage of time at APEE level

APEE 98 95 90 80 50 20 10 5 2

1 1550. 2580. 2820. 3800. 4900. 6800. 8230. 8980. 13200.

2 1310. 2230. 2430. 3210. 4070. 5140. 5810. 6630. 7120.

5 867. 1230. 1620. 2090. 2790. 3480. 3640. 3940. 4170.

10 457. 784. 951. 1240. 1730. 2230. 2400. 2510. 2840.

20 214. 367. 454. 611. 905. 1170. 1310. 1520. 1630.

25 161. 270. 342. 478. 699. 934. 1030. 1190. 1350.

30 120. 185. 260. 378. 567. 758. 873. 948. 1140.

40 66.1 106. 157. 212. 361. 602. 649. 727. 874.

50 32.5 59.8 78.7 96.4 224. 422. 494. 538. 625.

60 18.8 26.0 42.1 63.8 132. 265. 373. 423. 477.

70 10.4 13.3 28.3 42.0 77.3 165. 230. 266. 395.

75 8.39 11.0 22.3 34.0 61.5 130. 178. 220. 363.

80 6.71 8.10 16.3 26.3 50.0 107. 132. 175. 330.

90 2.53 5.41 8.28 14.6 29.5 66.2 94.2 118. 200.

95 1.90 3.36 6.20 9.51 23.5 46.0 64.9 89.4 164.

98 1.65 2.61 5.09 7.06 19.3 39.8 54.1 69.4 134.

99 1.47 2.42 4.03 6.15 17.8 35.4 51.7 60.7 114.

7-day mean streamflow (ft3/s) that was equaled or exceeded the indicated percentage of time at APEE level

APEE 98 95 90 80 50 20 10 5 2

1 1260. 1940. 2170. 3000. 3840. 5670. 6850. 7600. 10500.

2 1060. 1640. 1850. 2600. 3290. 4450. 4830. 6040. 7420.

5 881. 1210. 1530. 1780. 2430. 2890. 3270. 3500. 3900.

10 462. 865. 960. 1250. 1660. 2150. 2310. 2430. 2610.

20 201. 360. 507. 701. 985. 1330. 1460. 1530. 1740.

25 159. 297. 362. 520. 771. 1030. 1160. 1330. 1480.

30 113. 176. 276. 392. 638. 880. 973. 1130. 1290.

40 63.0 112. 166. 231. 386. 684. 724. 778. 979.

50 36.2 58.3 74.1 111. 247. 496. 573. 631. 740.

60 16.8 27.4 45.4 70.9 142. 287. 409. 464. 520.

70 10.3 13.5 30.0 47.9 82.0 186. 265. 304. 436.

75 8.07 11.7 22.2 33.6 64.9 153. 196. 255. 394.

80 6.91 8.31 17.3 27.4 52.9 125. 158. 222. 367.

90 2.65 5.66 9.19 14.7 31.9 76.2 102. 138. 244.

95 2.00 3.43 6.76 11.2 25.1 52.0 78.3 108. 182.

98 1.74 2.73 5.61 7.78 21.8 43.7 64.2 96.4 151.

99 1.58 2.58 4.69 6.79 19.0 39.8 56.0 77.2 136.
58 Methods for Estimating Selected Low-Flow Statistics and Development of Annual Flow-Duration Statistics for Ohio

03217500 Scioto River at La Rue, Ohio

Years analyzed = 20

Climatic year range = 1927–50

[APEE, annual percentage equaled or exceeded; ft3/s, cubic foot per second]

Daily mean streamflow (ft3/s) that was equaled or exceeded the indicated percentage of time at APEE level

APEE 95 90 80 70 50 30 20 10 5

1 439. 585. 1710. 1950. 2570. 3190. 3780. 3960. 4680.

2 283. 378. 1110. 1340. 1700. 2290. 2500. 2610. 3170.

5 168. 214. 633. 715. 955. 1340. 1490. 1690. 1840.

10 105. 145. 281. 359. 481. 679. 857. 955. 974.

20 50.0 74.1 122. 142. 213. 320. 375. 497. 533.

25 35.5 56.1 88.4 98.4 154. 244. 284. 378. 416.

30 24.8 41.5 58.6 76.6 106. 188. 233. 306. 350.

40 11.3 17.0 34.2 42.1 69.0 116. 155. 223. 232.

50 9.10 11.7 21.0 29.3 43.0 74.3 100. 153. 159.

60 6.98 8.76 14.6 19.1 26.2 47.8 70.2 105. 110.

70 5.73 6.58 10.4 12.3 16.5 24.3 38.7 63.3 74.4

75 3.98 5.80 8.56 10.3 14.0 17.4 30.4 48.7 63.3

80 3.93 4.79 7.20 8.95 12.0 15.8 24.5 41.3 45.8

90 3.81 3.93 5.00 5.78 8.25 10.7 16.8 23.5 29.4

95 3.02 3.49 3.92 4.55 6.00 8.53 11.8 14.9 23.5

98 3.01 3.21 3.71 3.93 4.60 7.64 8.90 14.8 15.9

99 3.01 3.15 3.66 3.93 4.20 7.40 8.63 13.8 14.9

7-day mean streamflow (ft3/s) that was equaled or exceeded the indicated percentage of time at APEE level

APEE 95 90 80 70 50 30 20 10 5

1 227. 377. 1220. 1410. 1500. 2020. 2230. 2460. 3460.

2 193. 349. 878. 969. 1380. 1530. 1940. 2070. 2570.

5 164. 206. 584. 716. 901. 1240. 1320. 1550. 1590.

10 99.2 120. 331. 386. 552. 780. 897. 962. 1000.

20 54.3 75.0 148. 168. 261. 417. 518. 589. 614.

25 41.3 55.6 109. 122. 187. 337. 393. 463. 513.

30 32.9 45.0 68.7 93.5 142. 236. 339. 400. 448.

40 13.2 18.9 44.8 52.2 82.6 149. 199. 292. 337.

50 7.96 12.7 25.3 31.3 55.6 89.8 125. 208. 237.

60 6.67 8.68 17.1 19.9 30.4 57.5 88.4 152. 166.

70 5.71 6.61 11.3 13.1 18.1 35.6 45.7 86.1 108.

75 4.97 6.00 9.43 10.8 15.3 27.4 35.3 60.8 85.9

80 4.44 5.19 8.17 9.83 12.7 20.4 28.6 50.1 65.7

90 3.91 4.19 5.46 6.61 8.62 11.5 17.4 27.3 29.9

95 3.31 3.75 4.21 5.54 6.88 9.27 12.3 16.3 24.7

98 3.02 3.35 3.80 4.74 5.58 8.75 10.1 15.3 16.9

99 3.01 3.24 3.73 4.32 5.15 8.49 9.33 15.0 16.6
Appendix 3 59

03218000 Little Scioto River above Marion, Ohio

Years analyzed = 32

Climatic year range = 1939–70

[APEE, annual percentage equaled or exceeded; ft3/s, cubic foot per second]

Daily mean streamflow (ft3/s) that was equaled or exceeded the indicated percentage of time at APEE level

APEE 95 90 80 70 50 30 20 10 5

1 274. 305. 408. 515. 596. 739. 803. 892. 1210.

2 168. 205. 320. 356. 427. 490. 546. 617. 744.

5 86.4 116. 144. 175. 229. 299. 325. 353. 383.

10 38.3 55.9 77.1 87.2 130. 169. 178. 195. 221.

20 16.0 19.6 30.7 38.6 57.5 79.3 89.6 94.5 111.

25 11.2 15.2 19.4 28.9 43.4 59.3 69.3 75.8 88.8

30 5.76 8.15 12.0 21.7 30.0 47.2 55.7 63.0 71.8

40 1.44 2.82 7.55 9.58 16.0 29.2 36.2 42.7 45.7

50 0.46 0.80 3.00 4.94 9.80 18.2 24.0 30.0 31.3

60 0.00 0.13 1.12 2.29 5.10 11.1 15.0 20.4 22.7

70 0.00 0.00 0.66 0.80 2.05 5.42 7.52 13.1 14.9

75 0.00 0.00 0.40 0.49 1.45 3.45 4.59 9.68 12.3

80 0.00 0.00 0.30 0.30 0.75 1.98 3.28 7.80 10.0

90 0.00 0.00 0.00 0.10 0.30 0.94 1.16 3.88 4.94

95 0.00 0.00 0.00 0.00 0.15 0.41 0.71 2.43 3.87

98 0.00 0.00 0.00 0.00 0.10 0.30 0.48 1.60 3.28

99 0.00 0.00 0.00 0.00 0.03 0.20 0.37 1.08 2.50

7-day mean streamflow (ft3/s) that was equaled or exceeded the indicated percentage of time at APEE level

APEE 95 90 80 70 50 30 20 10 5

1 178. 236. 291. 313. 380. 519. 611. 738. 1030.

2 146. 189. 237. 253. 314. 370. 452. 533. 573.

5 77.9 112. 163. 209. 229. 272. 297. 353. 419.

10 39.2 44.6 87.7 125. 148. 187. 197. 224. 238.

20 17.3 20.4 36.2 45.1 69.7 101. 111. 121. 135.

25 11.3 15.0 19.4 33.9 51.2 71.3 80.4 94.2 107.

30 6.69 8.34 13.7 25.1 36.9 55.0 68.3 74.2 85.3

40 1.65 2.78 7.18 10.3 17.5 35.2 44.5 52.7 57.8

50 0.62 0.94 3.62 5.18 10.4 21.1 26.7 37.3 39.5

60 0.03 0.22 1.17 2.31 5.28 12.8 19.0 27.4 29.2

70 0.00 0.00 0.66 1.02 2.26 6.54 9.26 15.5 17.8

75 0.00 0.00 0.41 0.61 1.53 3.74 5.63 12.5 13.2

80 0.00 0.00 0.28 0.40 0.86 2.22 4.07 9.39 10.8

90 0.00 0.00 0.07 0.17 0.37 0.97 1.57 5.08 6.33

95 0.00 0.00 0.00 0.01 0.19 0.50 0.76 2.94 4.12

98 0.00 0.00 0.00 0.00 0.14 0.39 0.61 1.63 3.69

99 0.00 0.00 0.00 0.00 0.09 0.25 0.44 1.40 3.37
60 Methods for Estimating Selected Low-Flow Statistics and Development of Annual Flow-Duration Statistics for Ohio

03219500 Scioto River near Prospect, Ohio

Years analyzed = 75

Climatic year range = 1926–2008

[APEE, annual percentage equaled or exceeded; ft3/s, cubic foot per second]

Daily mean streamflow (ft3/s) that was equaled or exceeded the indicated percentage of time at APEE level

APEE 98 95 90 80 50 20 10 5 2

1 1070. 1670. 2290. 3180. 4610. 6330. 7060. 7690. 8440.

2 719. 1190. 1950. 2340. 3640. 4710. 5540. 6030. 7010.

5 410. 682. 919. 1470. 2140. 3070. 3690. 4030. 4850.

10 270. 315. 486. 744. 1300. 1970. 2400. 2700. 2850.

20 127. 152. 258. 296. 589. 984. 1230. 1370. 1510.

25 94.2 115. 173. 215. 434. 739. 921. 1040. 1230.

30 72.4 90.8 126. 171. 346. 555. 706. 817. 977.

40 28.5 52.4 68.0 100. 217. 382. 450. 527. 652.

50 22.2 27.8 41.2 55.8 140. 264. 304. 371. 459.

60 17.0 21.0 29.2 38.2 87.2 177. 216. 256. 346.

70 15.0 17.0 20.2 28.2 49.8 118. 147. 189. 276.

75 13.8 15.0 17.0 23.2 39.0 93.6 118. 150. 251.

80 13.2 14.0 16.0 21.0 31.0 75.8 97.6 122. 218.

90 10.4 12.0 13.0 15.0 21.0 39.0 62.8 73.6 158.

95 8.31 10.2 11.0 13.0 19.0 27.2 45.5 55.7 118.

98 7.33 8.84 9.64 11.5 17.0 21.8 35.3 48.2 81.6

99 6.51 7.99 8.69 11.0 16.0 20.5 29.9 46.3 66.8

7-day mean streamflow (ft3/s) that was equaled or exceeded the indicated percentage of time at APEE level

APEE 98 95 90 80 50 20 10 5 2

1 770. 1140. 1810. 2420. 3530. 4860. 5700. 5900. 7140.

2 582. 930. 1550. 1980. 2920. 3720. 4190. 5030. 6050.

5 421. 604. 850. 1360. 2060. 2770. 3230. 3810. 4300.

10 230. 275. 539. 864. 1290. 1930. 2160. 2650. 2880.

20 123. 150. 256. 359. 720. 1110. 1420. 1540. 1610.

25 89.4 116. 175. 260. 534. 882. 1150. 1240. 1320.

30 72.8 98.8 124. 201. 417. 704. 883. 973. 1110.

40 26.7 57.3 75.4 109. 262. 445. 567. 708. 805.

50 22.1 28.5 42.3 65.9 150. 305. 392. 475. 638.

60 17.9 22.3 30.3 41.3 94.1 209. 264. 312. 470.

70 15.4 17.5 21.5 28.2 54.3 139. 172. 236. 335.

75 14.4 15.5 18.5 23.6 42.3 109. 140. 196. 288.

80 13.4 14.2 16.1 21.6 31.6 86.9 115. 159. 249.

90 11.1 12.2 13.4 16.2 22.8 45.5 72.4 88.7 181.

95 8.98 10.7 11.1 13.6 20.1 30.1 54.6 69.1 148.

98 7.70 9.68 10.4 12.2 17.9 23.3 41.6 50.1 107.

99 7.56 9.10 9.91 11.8 17.0 21.7 36.2 47.1 89.5
Appendix 3 61

03220000 Mill Creek near Bellepoint, Ohio

Years analyzed = 65

Climatic year range = 1944–2008

[APEE, annual percentage equaled or exceeded; ft3/s, cubic foot per second]

Daily mean streamflow (ft3/s) that was equaled or exceeded the indicated percentage of time at APEE level

APEE 98 95 90 80 50 20 10 5 2

1 746. 899. 1260. 1600. 2290. 2930. 3500. 3870. 3990.

2 349. 592. 901. 976. 1710. 2170. 2580. 2780. 2950.

5 131. 226. 356. 511. 797. 1240. 1310. 1550. 1630.

10 72.0 79.0 168. 211. 344. 596. 720. 788. 1010.

20 29.3 36.4 53.9 81.7 145. 232. 271. 342. 362.

25 23.3 27.3 34.3 57.0 97.0 152. 191. 233. 254.

30 15.7 20.9 24.6 40.4 74.4 123. 142. 185. 208.

40 7.02 11.6 14.0 25.8 46.0 75.5 94.0 122. 128.

50 4.50 6.50 9.96 15.4 32.0 53.7 62.0 77.6 84.4

60 3.09 4.22 6.84 10.4 20.4 37.8 43.2 56.3 64.6

70 2.06 3.05 5.23 6.73 12.0 24.8 30.0 38.7 47.4

75 1.70 2.42 4.33 5.32 9.80 20.0 25.8 30.3 39.9

80 1.36 2.00 3.43 4.48 7.70 16.0 19.8 25.7 34.8

90 0.73 1.10 1.46 3.02 5.34 10.0 12.4 17.4 22.2

95 0.53 0.80 0.96 1.28 4.34 7.42 9.26 13.6 17.6

98 0.20 0.43 0.60 0.97 3.40 6.29 7.54 9.48 14.4

99 0.10 0.22 0.49 0.87 3.23 5.63 6.41 7.22 12.5

7-day mean streamflow (ft3/s) that was equaled or exceeded the indicated percentage of time at APEE level

APEE 98 95 90 80 50 20 10 5 2

1 457. 567. 731. 958. 1410. 1990. 2100. 2230. 3490.

2 412. 431. 568. 705. 1050. 1380. 1630. 1730. 1800.

5 132. 223. 389. 487. 731. 1020. 1220. 1340. 1450.

10 66.3 82.6 214. 286. 466. 710. 772. 882. 992.

20 30.1 37.8 65.3 117. 213. 393. 469. 511. 553.

25 24.2 26.8 43.9 80.5 149. 297. 357. 405. 442.

30 17.7 23.0 28.8 48.5 109. 214. 269. 326. 365.

40 6.99 13.5 14.9 30.4 69.7 120. 156. 194. 241.

50 4.70 7.41 10.7 18.7 41.2 77.0 103. 118. 157.

60 3.20 4.56 7.79 12.4 26.0 44.6 61.4 81.6 89.3

70 2.12 3.32 5.08 7.30 14.2 31.5 38.8 50.8 64.2

75 1.75 2.39 4.43 5.58 10.6 24.1 31.4 40.3 50.2

80 1.45 2.07 3.47 5.07 8.41 20.3 23.5 30.0 43.8

90 0.87 1.16 1.49 3.41 5.84 12.3 14.8 20.5 29.0

95 0.56 0.79 1.05 1.60 4.43 8.49 11.0 15.4 23.1

98 0.37 0.58 0.74 1.08 4.06 7.13 8.90 13.4 18.1

99 0.27 0.38 0.70 1.03 3.79 6.75 7.75 10.8 15.8
62 Methods for Estimating Selected Low-Flow Statistics and Development of Annual Flow-Duration Statistics for Ohio

03223000 Olentangy River at Claridon, Ohio

Years analyzed = 51

Climatic year range = 1947–97

[APEE, annual percentage equaled or exceeded; ft3/s, cubic foot per second]

Daily mean streamflow (ft3/s) that was equaled or exceeded the indicated percentage of time at APEE level

APEE 98 95 90 80 50 20 10 5 2

1 487. 859. 1020. 1290. 1740. 2250. 2520. 3040. 3560.

2 367. 599. 745. 972. 1310. 1590. 1820. 2120. 2220.

5 245. 284. 382. 500. 752. 995. 1100. 1210. 1260.

10 124. 152. 171. 228. 408. 553. 692. 749. 774.

20 43.2 65.8 75.2 106. 169. 253. 317. 348. 383.

25 28.0 45.6 56.2 77.3 128. 196. 245. 269. 290.

30 19.6 33.6 40.4 57.9 98.4 155. 191. 213. 247.

40 9.96 19.0 23.4 30.2 62.0 101. 118. 147. 178.

50 6.13 9.56 13.6 18.4 46.0 70.4 81.2 106. 137.

60 4.04 5.38 8.34 11.4 27.4 45.8 59.4 71.0 111.

70 2.62 3.12 5.78 7.30 17.0 32.2 41.4 54.1 93.7

75 1.91 2.26 4.24 5.88 13.0 21.8 34.4 47.0 83.8

80 1.50 1.60 2.90 4.54 9.60 17.6 28.6 39.2 69.9

90 0.42 0.92 1.44 2.20 6.00 11.0 16.8 23.4 39.0

95 0.01 0.32 0.72 1.24 4.53 9.15 13.0 16.6 26.3

98 0.00 0.08 0.26 0.74 3.40 7.32 9.25 13.7 17.0

99 0.00 0.05 0.22 0.63 2.97 6.37 7.89 9.26 15.8

7-day mean streamflow (ft3/s) that was equaled or exceeded the indicated percentage of time at APEE level

APEE 98 95 90 80 50 20 10 5 2

1 318. 452. 685. 866. 1160. 1680. 1970. 2490. 3420.

2 291. 359. 531. 703. 937. 1230. 1500. 1570. 1690.

5 231. 272. 347. 448. 680. 839. 956. 1110. 1290.

10 130. 149. 182. 289. 427. 588. 632. 707. 747.

20 43.3 68.1 98.2 134. 216. 348. 415. 469. 482.

25 31.9 53.3 72.9 92.4 168. 255. 355. 393. 438.

30 21.0 38.0 44.0 68.7 124. 207. 283. 312. 362.

40 11.7 21.1 23.9 34.2 75.9 137. 159. 192. 250.

50 6.77 11.0 13.2 19.9 54.3 91.6 103. 139. 165.

60 3.95 5.43 8.84 12.0 32.3 57.4 72.1 98.3 134.

70 2.58 3.45 5.87 8.13 18.4 39.3 53.7 68.5 117.

75 2.12 2.53 4.58 6.39 15.0 27.5 41.9 60.7 104.

80 1.58 1.95 3.41 5.30 10.8 19.2 32.1 49.4 90.5

90 0.56 1.05 1.77 2.64 6.64 12.7 20.2 35.7 55.5

95 0.01 0.47 0.81 1.69 5.23 9.75 14.2 18.6 29.4

98 0.00 0.19 0.47 0.88 3.83 8.67 11.3 15.9 24.9

99 0.00 0.10 0.29 0.71 3.24 7.51 9.00 14.3 19.9
Appendix 3 63

03228300 Big Walnut Creek at Sunbury, Ohio

Years analyzed = 20

Climatic year range = 1989–2008

[APEE, annual percentage equaled or exceeded; ft3/s, cubic foot per second]

Daily mean streamflow (ft3/s) that was equaled or exceeded the indicated percentage of time at APEE level

APEE 95 90 80 70 50 30 20 10 5

1 572. 707. 1010. 1110. 1570. 1800. 1890. 2060. 2870.

2 342. 623. 652. 727. 1060. 1220. 1290. 1510. 1610.

5 158. 299. 319. 359. 539. 778. 790. 829. 1040.

10 94.1 135. 170. 176. 252. 329. 384. 424. 517.

20 33.0 53.6 78.1 85.1 111. 155. 170. 197. 212.

25 22.9 38.0 57.4 66.3 91.3 116. 132. 140. 148.

30 15.5 25.8 43.2 52.5 71.6 91.5 97.5 111. 121.

40 2.96 11.6 28.6 36.3 46.5 59.6 65.9 74.9 81.7

50 0.84 5.12 16.4 21.3 32.0 39.5 45.6 53.8 57.8

60 0.34 1.53 8.10 10.2 16.5 25.3 29.2 38.1 43.7

70 0.02 0.30 2.41 3.67 7.23 13.5 17.0 25.4 29.8

75 0.01 0.11 0.96 1.92 5.00 10.8 13.0 20.3 22.4

80 0.00 0.03 0.46 0.89 2.61 7.39 9.95 11.9 17.7

90 0.00 0.00 0.06 0.13 0.49 3.56 3.86 5.34 8.02

95 0.00 0.00 0.00 0.03 0.09 1.44 2.43 3.26 4.38

98 0.00 0.00 0.00 0.00 0.03 0.34 1.16 2.29 2.97

99 0.00 0.00 0.00 0.00 0.01 0.14 0.60 1.18 1.74

7-day mean streamflow (ft3/s) that was equaled or exceeded the indicated percentage of time at APEE level

APEE 95 90 80 70 50 30 20 10 5

1 426. 508. 562. 608. 765. 868. 926. 1170. 1640.

2 276. 439. 489. 516. 639. 743. 806. 882. 1160.

5 160. 289. 318. 359. 523. 597. 646. 741. 813.

10 109. 181. 203. 210. 354. 399. 443. 475. 484.

20 39.6 83.8 100. 109. 164. 251. 282. 321. 324.

25 23.0 48.2 78.9 86.3 134. 198. 222. 249. 278.

30 17.2 30.0 62.9 73.2 106. 144. 171. 186. 242.

40 2.79 13.6 34.3 46.9 68.1 80.6 96.9 128. 170.

50 0.96 7.15 18.9 27.2 41.8 53.3 70.4 76.3 100.

60 0.33 1.68 10.8 12.5 20.7 32.4 41.1 52.4 64.0

70 0.03 0.37 3.03 5.00 10.4 17.1 26.0 34.7 36.5

75 0.02 0.20 1.09 2.59 6.84 13.0 19.0 26.0 29.6

80 0.01 0.09 0.64 1.47 3.38 9.86 13.3 17.5 22.5

90 0.00 0.01 0.08 0.18 0.92 3.92 5.20 9.11 11.3

95 0.00 0.00 0.01 0.05 0.22 1.87 2.74 5.06 6.94

98 0.00 0.00 0.00 0.01 0.08 1.01 1.64 4.16 4.91

99 0.00 0.00 0.00 0.01 0.05 0.41 1.27 3.32 3.42
64 Methods for Estimating Selected Low-Flow Statistics and Development of Annual Flow-Duration Statistics for Ohio

03230500 Big Darby Creek at Darbyville, Ohio

Years analyzed = 83

Climatic year range = 1922–2008

[APEE, annual percentage equaled or exceeded; ft3/s, cubic foot per second]

Daily mean streamflow (ft3/s) that was equaled or exceeded the indicated percentage of time at APEE level

APEE 98 95 90 80 50 20 10 5 2

1 459. 1910. 2470. 3150. 5130. 6540. 7280. 8380. 10200.

2 340. 1260. 1640. 2150. 3440. 4640. 5340. 5940. 7470.

5 227. 609. 941. 1180. 1890. 2720. 3090. 3650. 3880.

10 134. 383. 519. 654. 1060. 1750. 1920. 2110. 2280.

20 62.4 179. 258. 360. 546. 918. 1080. 1130. 1240.

25 50.6 141. 195. 265. 425. 730. 857. 891. 975.

30 42.0 95.0 155. 215. 350. 597. 708. 733. 820.

40 27.8 39.4 88.0 144. 250. 399. 509. 551. 599.

50 21.4 30.0 54.2 93.6 180. 281. 354. 398. 453.

60 17.4 20.2 39.6 52.0 110. 194. 249. 306. 361.

70 14.6 18.0 29.4 37.8 76.0 133. 173. 246. 276.

75 12.4 15.2 26.2 32.8 61.0 105. 143. 211. 248.

80 9.64 13.3 20.3 27.0 48.0 83.4 126. 181. 211.

90 6.17 7.38 12.8 18.5 33.0 55.2 81.2 110. 163.

95 4.08 5.55 8.22 14.5 27.0 44.0 59.7 84.9 132.

98 2.54 4.39 6.00 11.9 23.0 39.3 46.8 74.0 107.

99 2.19 3.12 5.39 10.5 21.7 38.0 43.0 68.5 89.8

7-day mean streamflow (ft3/s) that was equaled or exceeded the indicated percentage of time at APEE level

APEE 98 95 90 80 50 20 10 5 2

1 376. 1350. 1640. 1980. 3260. 4790. 5480. 6450. 9740.

2 281. 1120. 1240. 1720. 2680. 3610. 4080. 4390. 6050.

5 228. 663. 897. 1150. 1950. 2510. 3020. 3200. 3590.

10 128. 392. 593. 772. 1210. 1710. 1930. 2090. 2250.

20 62.8 184. 246. 387. 631. 1070. 1220. 1390. 1570.

25 50.8 137. 190. 285. 501. 882. 998. 1180. 1290.

30 40.8 88.7 145. 237. 371. 704. 853. 952. 1100.

40 26.8 41.8 92.3 152. 268. 485. 600. 661. 750.

50 21.5 30.9 54.9 99.6 193. 321. 441. 512. 552.

60 17.6 20.5 41.1 52.3 119. 218. 293. 371. 425.

70 14.4 18.1 29.6 40.6 79.7 145. 208. 278. 322.

75 13.0 15.6 25.6 33.9 64.7 117. 160. 243. 276.

80 10.2 13.8 21.2 27.4 47.7 94.7 133. 211. 234.

90 6.09 7.71 13.5 18.4 35.6 60.3 87.7 118. 180.

95 4.32 5.92 8.34 15.4 28.3 45.7 61.5 89.5 149.

98 3.39 4.67 6.78 12.8 24.6 41.4 56.4 77.1 131.

99 2.67 3.89 6.23 11.4 23.9 39.6 44.8 73.8 103.
Appendix 3 65

03232000 Paint Creek near Greenfield, Ohio

Years analyzed = 51

Climatic year range = 1927–2008

[APEE, annual percentage equaled or exceeded; ft3/s, cubic foot per second]

Daily mean streamflow (ft3/s) that was equaled or exceeded the indicated percentage of time at APEE level

APEE 98 95 90 80 50 20 10 5 2

1 273. 538. 772. 1480. 2560. 3970. 4430. 5630. 6190.

2 174. 359. 687. 1050. 1760. 2660. 3000. 3520. 4000.

5 97.0 175. 407. 619. 970. 1430. 1670. 1950. 2330.

10 52.6 118. 208. 432. 589. 877. 983. 1190. 1330.

20 25.1 55.2 112. 212. 293. 475. 565. 600. 661.

25 16.9 42.4 88.9 151. 220. 384. 443. 462. 521.

30 11.8 31.2 68.1 103. 180. 308. 355. 376. 426.

40 5.46 14.2 29.8 62.4 128. 207. 256. 261. 324.

50 3.22 6.78 11.7 35.8 85.0 147. 178. 200. 243.

60 2.47 3.16 5.70 22.6 51.0 106. 130. 156. 196.

70 1.41 2.08 4.54 11.3 26.0 76.6 91.5 123. 130.

75 0.72 1.46 3.78 7.58 20.0 58.2 73.4 107. 111.

80 0.44 1.16 2.52 4.55 15.0 40.1 60.8 89.7 95.3

90 0.20 0.29 1.04 2.21 8.04 19.0 35.2 56.1 69.9

95 0.10 0.17 0.60 1.40 4.29 9.60 23.9 44.8 57.2

98 0.03 0.12 0.25 0.90 2.80 7.50 13.1 29.8 40.9

99 0.00 0.10 0.21 0.46 2.50 6.69 12.0 24.8 36.7

7-day mean streamflow (ft3/s) that was equaled or exceeded the indicated percentage of time at APEE level

APEE 98 95 90 80 50 20 10 5 2

1 206. 452. 630. 1030. 1880. 3080. 3390. 4350. 5290.

2 127. 299. 473. 912. 1360. 2100. 2420. 2760. 3540.

5 86.0 187. 397. 621. 939. 1370. 1740. 1820. 1860.

10 47.8 120. 240. 441. 650. 910. 1050. 1110. 1190.

20 20.9 58.9 114. 219. 323. 558. 607. 715. 789.

25 14.5 43.8 90.4 181. 249. 447. 509. 622. 690.

30 12.2 32.9 62.5 127. 205. 370. 433. 504. 534.

40 5.79 16.6 28.5 70.8 149. 248. 294. 336. 356.

50 3.08 7.17 11.7 41.8 90.7 166. 223. 243. 273.

60 2.63 3.28 5.85 23.7 57.7 125. 151. 190. 217.

70 1.31 2.03 4.79 10.7 32.0 84.7 104. 145. 173.

75 0.86 1.69 4.18 8.42 24.0 68.4 84.2 121. 133.

80 0.48 1.11 3.27 5.61 17.1 47.5 69.0 97.8 118.

90 0.27 0.67 1.66 2.42 8.44 20.1 38.9 62.7 84.1

95 0.16 0.50 0.78 1.75 5.19 10.6 27.3 48.9 68.1

98 0.09 0.17 0.41 1.15 3.43 8.68 18.6 32.4 54.9

99 0.05 0.14 0.24 0.77 2.73 7.90 12.8 27.4 49.5
66 Methods for Estimating Selected Low-Flow Statistics and Development of Annual Flow-Duration Statistics for Ohio

03235500 Tar Hollow Creek at Tar Hollow State Park, Ohio

Years analyzed = 31

Climatic year range = 1947–77

[APEE, annual percentage equaled or exceeded; ft3/s, cubic foot per second]

Daily mean streamflow (ft3/s) that was equaled or exceeded the indicated percentage of time at APEE level

APEE 95 90 80 70 50 30 20 10 5

1 6.40 7.88 10.3 12.7 16.0 21.9 25.8 28.0 31.1

2 4.19 5.61 6.59 7.97 9.84 13.4 15.4 16.4 21.1

5 1.87 2.65 3.32 3.83 5.26 7.26 7.77 8.69 9.50

10 1.12 1.62 2.06 2.30 2.93 3.84 4.24 4.80 5.20

20 0.45 0.72 1.00 1.07 1.48 1.78 2.22 2.78 2.94

25 0.20 0.42 0.57 0.75 1.00 1.44 1.82 2.24 2.38

30 0.00 0.04 0.32 0.48 0.70 1.14 1.40 1.74 2.05

40 0.00 0.00 0.01 0.20 0.40 0.69 0.80 1.24 1.52

50 0.00 0.00 0.00 0.00 0.20 0.35 0.48 0.60 1.20

60 0.00 0.00 0.00 0.00 0.06 0.16 0.20 0.29 0.64

70 0.00 0.00 0.00 0.00 0.00 0.05 0.10 0.18 0.30

75 0.00 0.00 0.00 0.00 0.00 0.02 0.06 0.10 0.17

80 0.00 0.00 0.00 0.00 0.00 0.02 0.04 0.10 0.14

90 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.02 0.04

95 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.01

98 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00

99 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00

7-day mean streamflow (ft3/s) that was equaled or exceeded the indicated percentage of time at APEE level

APEE 95 90 80 70 50 30 20 10 5

1 4.17 4.81 5.70 6.86 9.16 11.8 14.1 18.7 25.1

2 3.58 4.42 4.83 5.80 7.47 10.1 10.5 12.5 14.6

5 2.87 3.44 3.63 3.96 5.47 7.05 7.78 8.33 9.37

10 1.32 1.64 2.52 2.56 3.17 4.51 5.48 6.18 6.63

20 0.35 0.81 1.23 1.37 1.74 2.29 2.99 3.45 3.95

25 0.23 0.48 0.70 0.87 1.20 1.90 2.26 2.80 3.03

30 0.05 0.11 0.48 0.61 0.84 1.66 2.01 2.20 2.55

40 0.00 0.00 0.04 0.24 0.51 0.84 1.12 1.50 1.85

50 0.00 0.00 0.00 0.08 0.24 0.46 0.54 0.83 1.32

60 0.00 0.00 0.00 0.00 0.10 0.21 0.28 0.33 0.73

70 0.00 0.00 0.00 0.00 0.01 0.09 0.14 0.19 0.37

75 0.00 0.00 0.00 0.00 0.00 0.05 0.10 0.14 0.24

80 0.00 0.00 0.00 0.00 0.00 0.03 0.05 0.10 0.19

90 0.00 0.00 0.00 0.00 0.00 0.01 0.02 0.03 0.07

95 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.01 0.03

98 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00

99 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00
Appendix 3 67

03237280 Upper Twin Creek at McGaw, Ohio

Years analyzed = 45

Climatic year range = 1964–2008

[APEE, annual percentage equaled or exceeded; ft3/s, cubic foot per second]

Daily mean streamflow (ft3/s) that was equaled or exceeded the indicated percentage of time at APEE level

APEE 95 90 80 70 50 30 20 10 5

1 64.0 73.2 104. 126. 156. 224. 260. 326. 352.

2 43.6 53.6 66.8 74.0 104. 138. 162. 190. 212.

5 25.3 31.1 39.8 42.7 55.7 65.0 71.3 101. 113.

10 15.3 16.8 23.6 26.1 30.0 40.0 42.0 53.0 56.7

20 7.30 9.88 11.0 14.0 17.0 22.8 24.8 28.1 30.9

25 5.88 7.44 8.27 9.74 14.0 17.4 19.9 23.4 24.7

30 4.32 5.48 6.09 7.08 10.2 14.0 17.0 19.1 20.0

40 1.00 1.90 2.93 3.70 5.96 9.08 11.5 13.4 15.4

50 0.34 0.47 1.26 1.70 3.10 6.12 7.30 8.94 11.0

60 0.10 0.19 0.48 0.80 1.54 2.62 3.79 5.22 7.97

70 0.06 0.12 0.21 0.36 0.69 1.38 1.82 2.56 5.80

75 0.01 0.05 0.13 0.21 0.42 0.89 1.18 1.68 4.55

80 0.00 0.02 0.07 0.10 0.25 0.54 0.80 1.30 3.13

90 0.00 0.00 0.00 0.04 0.09 0.29 0.38 0.61 1.70

95 0.00 0.00 0.00 0.00 0.05 0.13 0.22 0.48 1.20

98 0.00 0.00 0.00 0.00 0.02 0.11 0.15 0.35 0.88

99 0.00 0.00 0.00 0.00 0.02 0.09 0.15 0.28 0.69

7-day mean streamflow (ft3/s) that was equaled or exceeded the indicated percentage of time at APEE level

APEE 95 90 80 70 50 30 20 10 5

1 34.6 46.0 60.1 73.2 95.3 126. 138. 168. 200.

2 33.0 40.2 51.8 59.0 72.6 93.9 105. 134. 151.

5 23.2 29.3 38.5 41.2 52.6 68.5 80.7 92.3 96.6

10 16.9 18.9 26.3 30.4 39.3 44.0 48.2 56.4 67.2

20 8.22 12.0 14.5 17.9 22.3 27.3 31.1 37.6 43.2

25 6.70 9.55 11.3 12.9 15.4 20.8 24.2 30.3 37.8

30 4.97 7.00 7.83 9.19 12.3 17.2 18.9 26.6 28.6

40 1.67 2.71 3.79 4.31 7.31 11.9 13.6 19.6 20.5

50 0.39 0.77 1.91 2.18 3.61 7.27 8.81 12.3 15.7

60 0.13 0.21 0.70 1.01 1.97 3.49 5.37 6.93 11.0

70 0.07 0.11 0.25 0.45 0.81 1.74 2.63 3.81 7.32

75 0.04 0.06 0.15 0.27 0.64 1.13 1.80 2.59 6.45

80 0.01 0.03 0.08 0.16 0.34 0.78 1.19 1.70 4.23

90 0.00 0.00 0.01 0.04 0.11 0.40 0.48 0.83 2.21

95 0.00 0.00 0.00 0.01 0.06 0.15 0.29 0.54 1.38

98 0.00 0.00 0.00 0.00 0.04 0.13 0.22 0.46 1.03

99 0.00 0.00 0.00 0.00 0.02 0.11 0.16 0.40 0.91
68 Methods for Estimating Selected Low-Flow Statistics and Development of Annual Flow-Duration Statistics for Ohio

03237500 Ohio Brush Creek near West Union, Ohio

Years analyzed = 76

Climatic year range = 1927–2008

[APEE, annual percentage equaled or exceeded; ft3/s, cubic foot per second]

Daily mean streamflow (ft3/s) that was equaled or exceeded the indicated percentage of time at APEE level

APEE 98 95 90 80 50 20 10 5 2

1 2000. 3270. 3760. 4280. 6130. 8790. 9930. 11100. 13200.

2 1040. 1980. 2390. 2860. 4180. 5540. 6540. 6860. 7990.

5 487. 857. 1060. 1310. 2000. 2500. 2880. 3380. 3820.

10 231. 374. 505. 677. 988. 1310. 1610. 1940. 2050.

20 123. 177. 232. 316. 451. 617. 796. 895. 1020.

25 89.1 135. 183. 228. 352. 470. 618. 685. 765.

30 58.8 104. 142. 174. 264. 374. 486. 549. 611.

40 24.1 58.5 75.8 99.8 174. 254. 345. 373. 447.

50 11.7 16.0 24.9 54.8 108. 168. 236. 265. 301.

60 3.51 5.82 9.97 32.6 62.5 122. 151. 197. 222.

70 1.38 2.90 5.07 13.8 35.9 73.2 99.4 129. 168.

75 0.81 2.09 3.94 8.44 22.3 54.8 82.2 109. 139.

80 0.63 1.48 2.58 6.12 16.0 38.8 68.9 76.1 110.

90 0.22 0.75 1.02 2.37 7.90 18.0 35.3 51.2 64.4

95 0.13 0.26 0.55 0.88 4.78 11.2 22.0 31.5 49.2

98 0.05 0.13 0.28 0.59 3.32 8.68 15.6 18.2 40.2

99 0.05 0.13 0.20 0.46 2.55 8.00 12.9 14.5 36.2

7-day mean streamflow (ft3/s) that was equaled or exceeded the indicated percentage of time at APEE level

APEE 98 95 90 80 50 20 10 5 2

1 1080. 1390. 1980. 2280. 3090. 4630. 6300. 6700. 11200.

2 922. 1290. 1590. 1970. 2510. 3620. 4480. 5480. 6750.

5 508. 990. 1110. 1340. 1820. 2450. 2640. 2830. 3310.

10 270. 553. 693. 853. 1230. 1640. 1860. 2040. 2200.

20 141. 234. 329. 438. 661. 957. 1080. 1310. 1390.

25 107. 177. 242. 336. 516. 739. 917. 1140. 1200.

30 60.1 126. 204. 246. 400. 587. 755. 861. 941.

40 32.4 64.2 92.9 129. 246. 382. 512. 595. 661.

50 13.8 19.6 33.2 74.4 152. 262. 356. 400. 516.

60 4.11 6.07 11.7 44.6 86.0 169. 219. 299. 334.

70 1.49 2.88 5.41 19.0 46.3 96.5 149. 186. 251.

75 0.92 2.06 4.03 10.9 31.9 72.0 112. 135. 213.

80 0.72 1.51 3.09 7.53 21.7 55.6 87.8 114. 168.

90 0.22 0.79 1.17 2.97 10.1 30.1 48.5 66.4 82.9

95 0.14 0.32 0.67 1.03 5.22 16.5 34.4 41.0 66.0

98 0.09 0.19 0.35 0.79 3.95 11.2 20.6 29.2 55.4

99 0.05 0.14 0.26 0.65 3.18 9.60 17.1 22.6 50.9
Appendix 3 69

03238500 White Oak Creek near Georgetown, Ohio

Years analyzed = 79

Climatic year range = 1925–2008

[APEE, annual percentage equaled or exceeded; ft3/s, cubic foot per second]

Daily mean streamflow (ft3/s) that was equaled or exceeded the indicated percentage of time at APEE level

APEE 98 95 90 80 50 20 10 5 2

1 1280. 2220. 2520. 3140. 4500. 5760. 6400. 7230. 8180.

2 655. 973. 1650. 2030. 2930. 3750. 4310. 5250. 5460.

5 194. 375. 518. 784. 1220. 1760. 2140. 2450. 3010.

10 83.2 136. 245. 362. 517. 793. 1010. 1140. 1330.

20 36.4 62.0 101. 130. 193. 281. 387. 430. 535.

25 24.4 46.5 82.0 91.0 140. 210. 277. 312. 346.

30 16.1 34.0 58.7 68.0 109. 155. 216. 225. 260.

40 8.04 19.0 26.0 41.0 71.6 102. 138. 147. 173.

50 3.24 7.40 11.0 26.0 43.0 70.0 97.0 103. 124.

60 0.72 3.58 6.28 14.0 26.0 46.0 60.0 75.6 89.0

70 0.12 1.00 3.40 7.93 16.0 27.8 43.0 55.0 60.4

75 0.06 0.50 2.50 5.50 12.0 23.0 34.0 45.0 50.0

80 0.00 0.10 0.90 3.64 7.86 18.0 26.6 35.0 39.4

90 0.00 0.00 0.00 0.60 3.32 9.60 14.0 18.0 25.4

95 0.00 0.00 0.00 0.22 1.60 5.13 11.0 13.0 18.2

98 0.00 0.00 0.00 0.00 0.69 2.80 7.53 8.96 12.4

99 0.00 0.00 0.00 0.00 0.46 2.57 4.99 7.02 9.74

7-day mean streamflow (ft3/s) that was equaled or exceeded the indicated percentage of time at APEE level

APEE 98 95 90 80 50 20 10 5 2

1 633. 936. 1180. 1460. 2180. 2930. 3580. 3910. 4490.

2 532. 760. 1020. 1240. 1650. 2110. 2730. 3330. 3600.

5 267. 623. 760. 887. 1220. 1540. 1660. 2080. 2180.

10 118. 199. 406. 561. 756. 1040. 1160. 1330. 1520.

20 46.2 93.1 156. 235. 353. 577. 675. 798. 865.

25 27.6 67.6 125. 156. 256. 423. 554. 630. 780.

30 17.5 47.3 78.7 111. 188. 326. 475. 491. 644.

40 8.66 22.8 33.6 52.1 112. 213. 289. 315. 364.

50 3.76 9.33 16.4 34.0 64.0 120. 169. 211. 270.

60 1.41 4.15 7.09 18.1 37.6 75.1 106. 137. 152.

70 0.32 1.46 4.40 9.16 21.1 38.6 67.6 85.1 111.

75 0.09 1.02 2.90 6.54 15.4 30.4 52.4 71.7 92.3

80 0.05 0.32 1.39 4.56 11.8 22.9 37.7 52.6 73.4

90 0.00 0.00 0.22 0.89 3.91 13.9 22.3 26.0 38.3

95 0.00 0.00 0.00 0.40 2.27 7.39 13.8 17.7 29.3

98 0.00 0.00 0.00 0.22 1.50 5.00 10.6 14.6 21.8

99 0.00 0.00 0.00 0.14 0.85 3.97 7.53 11.4 17.7
70 Methods for Estimating Selected Low-Flow Statistics and Development of Annual Flow-Duration Statistics for Ohio

03240000 Little Miami River near Oldtown, Ohio

Years analyzed = 56

Climatic year range = 1953–2008

[APEE, annual percentage equaled or exceeded; ft3/s, cubic foot per second]

Daily mean streamflow (ft3/s) that was equaled or exceeded the indicated percentage of time at APEE level

APEE 98 95 90 80 50 20 10 5 2

1 183. 391. 431. 552. 970. 1540. 2030. 2300. 2800.

2 135. 279. 313. 393. 654. 933. 1200. 1300. 1350.

5 92.9 166. 210. 236. 387. 549. 597. 690. 774.

10 74.2 126. 135. 160. 233. 349. 409. 433. 505.

20 50.3 68.5 85.3 106. 149. 225. 264. 279. 282.

25 40.0 58.4 67.8 86.5 129. 190. 227. 240. 249.

30 34.5 48.8 55.1 73.6 112. 165. 201. 208. 215.

40 25.4 30.8 38.4 54.5 86.1 129. 152. 166. 177.

50 18.4 21.9 28.8 39.2 69.0 104. 126. 134. 149.

60 14.3 17.7 21.8 27.8 48.7 81.8 96.6 118. 134.

70 11.4 14.9 16.1 21.4 36.0 59.9 77.9 99.9 123.

75 11.3 13.0 14.9 19.0 29.5 53.4 68.8 84.3 115.

80 10.1 11.8 13.3 17.0 27.5 46.9 57.6 76.5 108.

90 8.43 9.11 10.9 13.8 20.8 36.0 45.1 57.2 91.5

95 6.87 8.21 9.26 12.0 19.0 31.2 41.2 49.2 83.5

98 5.91 7.49 8.09 10.4 17.0 27.3 36.2 41.8 72.7

99 5.68 7.17 7.89 9.98 16.0 25.7 35.6 38.0 68.1

7-day mean streamflow (ft3/s) that was equaled or exceeded the indicated percentage of time at APEE level

APEE 98 95 90 80 50 20 10 5 2

1 145. 292. 328. 406. 729. 1140. 1560. 1710. 1810.

2 129. 228. 261. 341. 511. 805. 1070. 1160. 1280.

5 92.2 171. 191. 245. 393. 538. 622. 769. 789.

10 73.2 127. 140. 175. 260. 379. 431. 476. 519.

20 50.7 67.0 87.3 109. 163. 260. 294. 309. 318.

25 39.7 57.3 64.0 93.4 138. 223. 248. 272. 286.

30 34.0 46.9 56.3 76.6 120. 193. 218. 234. 256.

40 26.3 30.9 40.4 55.9 92.4 140. 169. 183. 215.

50 20.1 22.0 30.2 39.4 70.7 109. 132. 154. 164.

60 13.2 17.3 22.7 27.8 52.1 87.4 110. 129. 150.

70 11.7 14.4 16.2 21.5 37.9 66.4 84.5 104. 137.

75 11.2 13.2 14.6 19.6 30.7 57.6 75.4 90.2 130.

80 10.6 11.8 13.2 17.2 27.9 49.9 61.3 81.8 122.

90 8.74 9.48 10.9 13.5 21.4 36.4 45.7 61.9 103.

95 7.33 8.36 9.48 12.0 18.9 33.0 41.7 51.5 94.1

98 6.30 7.60 8.80 11.1 17.9 28.1 39.6 45.2 84.6

99 5.85 7.47 8.20 10.6 17.4 27.2 38.3 43.3 73.1
Appendix 3 71

03241500 Massies Creek at Wilberforce, Ohio

Years analyzed = 56

Climatic year range = 1953–2008

[APEE, annual percentage equaled or exceeded; ft3/s, cubic foot per second]

Daily mean streamflow (ft3/s) that was equaled or exceeded the indicated percentage of time at APEE level

APEE 98 95 90 80 50 20 10 5 2

1 95.2 210. 287. 357. 583. 904. 1040. 1130. 1720.

2 68.4 146. 217. 251. 379. 599. 699. 780. 884.

5 41.9 90.8 128. 152. 236. 336. 389. 427. 484.

10 30.1 56.8 79.3 93.9 144. 209. 241. 261. 301.

20 18.5 35.6 41.0 52.3 79.6 118. 140. 158. 173.

25 14.5 24.9 30.5 43.1 66.3 96.9 112. 130. 138.

30 11.6 20.0 21.7 34.0 53.5 81.4 96.1 109. 113.

40 6.70 11.2 16.4 24.4 40.6 62.0 72.5 77.3 91.3

50 3.56 7.42 11.4 16.8 30.8 49.2 54.9 65.2 72.9

60 2.25 5.16 6.81 11.4 21.0 35.2 42.3 54.3 57.7

70 2.02 3.91 4.67 7.37 14.0 25.6 34.6 42.1 49.9

75 1.98 3.10 4.17 6.25 11.5 21.2 30.6 38.1 46.7

80 1.45 2.62 3.75 5.22 8.49 18.0 25.0 30.9 42.2

90 0.81 1.78 2.64 3.62 5.96 10.6 16.3 19.3 33.8

95 0.57 1.34 2.10 2.84 4.65 8.38 12.1 17.9 29.9

98 0.48 1.11 1.69 2.40 4.35 7.29 10.0 15.3 22.5

99 0.39 0.99 1.47 2.11 4.13 6.83 9.20 15.0 18.2

7-day mean streamflow (ft3/s) that was equaled or exceeded the indicated percentage of time at APEE level

APEE 98 95 90 80 50 20 10 5 2

1 75.3 161. 201. 262. 426. 605. 834. 963. 1060.

2 62.3 121. 171. 216. 305. 490. 522. 641. 697.

5 43.9 82.1 116. 143. 226. 325. 372. 409. 520.

10 31.1 64.9 76.4 96.5 157. 226. 271. 282. 300.

20 17.7 35.4 41.4 56.4 94.2 135. 166. 175. 208.

25 14.2 25.4 30.3 44.4 74.9 115. 138. 154. 177.

30 11.5 21.2 24.1 35.7 60.6 95.0 118. 133. 144.

40 7.50 12.2 16.8 26.1 45.8 70.6 87.0 90.6 111.

50 3.19 7.13 12.4 16.7 32.6 52.7 61.1 72.3 85.2

60 2.51 5.45 7.11 11.8 21.7 39.1 47.0 58.9 67.2

70 2.13 3.91 4.58 7.36 14.8 28.9 37.8 47.8 56.1

75 2.01 3.21 4.18 6.49 11.7 23.1 33.5 42.1 52.6

80 1.65 2.83 3.93 5.25 9.00 19.6 27.9 36.7 50.2

90 0.97 1.78 2.82 3.91 6.61 11.9 17.0 21.6 39.9

95 0.71 1.42 2.29 3.17 4.92 9.02 12.6 17.8 35.1

98 0.50 1.19 1.89 2.59 4.56 7.97 11.3 17.0 28.1

99 0.43 1.16 1.67 2.31 4.40 7.46 10.4 15.9 25.5
72 Methods for Estimating Selected Low-Flow Statistics and Development of Annual Flow-Duration Statistics for Ohio

03260700 Bokengehalas Creek near De Graff, Ohio

Years analyzed = 33

Climatic year range = 1958–90

[APEE, annual percentage equaled or exceeded; ft3/s, cubic foot per second]

Daily mean streamflow (ft3/s) that was equaled or exceeded the indicated percentage of time at APEE level

APEE 95 90 80 70 50 30 20 10 5

1 109. 151. 176. 217. 277. 324. 356. 390. 507.

2 78.5 92.8 108. 138. 178. 204. 246. 265. 297.

5 42.8 59.2 68.5 78.8 105. 125. 137. 170. 196.

10 30.4 34.5 44.0 53.8 66.8 82.6 89.9 117. 130.

20 18.9 19.4 25.8 32.2 43.0 49.4 60.0 69.9 84.1

25 14.1 16.4 21.4 27.4 37.5 41.6 51.8 61.5 71.9

30 12.1 13.8 19.0 23.4 33.0 37.5 45.5 52.6 63.2

40 8.68 10.0 14.0 16.2 23.6 29.0 36.4 43.0 50.3

50 6.84 8.00 10.7 12.2 18.0 23.6 27.4 35.8 41.3

60 5.61 6.60 7.97 9.82 15.0 18.8 22.0 28.8 31.5

70 5.21 5.76 7.10 7.90 12.0 14.8 18.4 21.6 25.8

75 4.70 5.60 6.66 7.56 11.0 13.0 16.6 20.0 22.6

80 4.67 5.20 6.14 7.16 9.60 11.8 14.2 18.0 20.5

90 4.11 4.57 5.60 6.00 7.96 9.41 11.2 13.8 14.6

95 3.88 4.34 5.01 5.34 7.20 8.92 10.1 12.0 13.6

98 3.41 4.00 4.29 4.72 6.40 7.98 9.56 10.2 13.3

99 3.22 3.72 3.89 4.36 6.40 7.73 8.70 9.93 12.6

7-day mean streamflow (ft3/s) that was equaled or exceeded the indicated percentage of time at APEE level

APEE 95 90 80 70 50 30 20 10 5

1 68.0 84.6 109. 157. 180. 241. 259. 295. 364.

2 58.8 78.4 95.5 129. 145. 170. 183. 234. 248.

5 43.4 53.1 67.7 82.1 105. 124. 133. 168. 186.

10 29.5 32.8 46.3 50.0 69.3 90.1 95.4 114. 136.

20 16.9 20.3 27.3 33.6 47.9 55.7 63.2 85.4 93.6

25 14.6 18.2 22.7 29.9 40.9 47.9 55.6 71.6 78.5

30 12.5 14.5 20.1 25.4 35.7 40.0 50.0 59.9 69.8

40 8.87 10.1 14.9 17.9 23.4 32.5 37.8 49.8 56.6

50 6.67 8.12 10.8 13.5 18.7 25.9 31.3 39.4 48.0

60 5.90 6.69 8.17 10.0 15.7 20.1 23.9 30.5 34.6

70 5.35 6.02 7.40 8.39 12.6 15.9 20.5 23.1 29.0

75 5.09 5.74 6.95 7.81 11.4 14.3 17.0 20.9 23.4

80 4.80 5.53 6.49 7.28 9.86 12.5 15.2 19.3 21.4

90 4.26 4.98 5.65 6.19 8.44 10.1 12.7 15.0 15.7

95 3.96 4.43 5.30 5.55 7.29 9.55 11.1 12.8 14.4

98 3.70 4.26 4.77 5.23 6.74 8.23 9.83 11.7 13.7

99 3.47 3.93 4.40 5.01 6.57 8.13 9.60 10.5 13.4
Appendix 3 73

03264000 Greenville Creek near Bradford, Ohio

Years analyzed = 75

Climatic year range = 1931–2008

[APEE, annual percentage equaled or exceeded; ft3/s, cubic foot per second]

Daily mean streamflow (ft3/s) that was equaled or exceeded the indicated percentage of time at APEE level

APEE 98 95 90 80 50 20 10 5 2

1 321. 488. 855. 1190. 1840. 2490. 3170. 3390. 4000.

2 239. 347. 542. 775. 1310. 1760. 2120. 2590. 2720.

5 145. 234. 279. 420. 732. 1030. 1160. 1300. 1400.

10 98.9 149. 176. 216. 426. 569. 677. 719. 748.

20 58.3 84.2 101. 121. 211. 314. 372. 399. 456.

25 45.6 68.6 82.6 101. 175. 253. 295. 329. 374.

30 35.9 57.9 67.8 84.1 147. 211. 250. 272. 303.

40 21.6 37.2 50.2 57.1 105. 154. 182. 202. 221.

50 16.0 27.2 34.6 44.6 76.0 116. 141. 154. 182.

60 14.7 21.7 28.2 35.5 58.0 91.9 105. 118. 152.

70 13.5 18.4 22.4 27.0 42.1 68.0 87.0 96.0 128.

75 13.5 15.0 20.8 24.0 38.0 58.6 70.0 87.2 118.

80 12.0 13.8 18.1 22.0 34.0 49.0 59.8 79.3 111.

90 9.85 12.6 14.0 17.0 27.0 37.6 46.6 64.5 89.0

95 8.62 9.63 11.7 14.0 23.3 31.3 38.4 58.3 70.9

98 7.18 8.25 10.7 12.1 21.0 28.9 33.6 51.1 58.1

99 6.66 7.67 9.19 11.1 21.0 27.5 32.3 48.6 55.0

7-day mean streamflow (ft3/s) that was equaled or exceeded the indicated percentage of time at APEE level

APEE 98 95 90 80 50 20 10 5 2

1 213. 396. 508. 833. 1330. 1720. 2040. 2670. 2900.

2 197. 324. 403. 693. 966. 1330. 1570. 1910. 2380.

5 152. 227. 290. 422. 674. 930. 1050. 1280. 1390.

10 98.3 145. 172. 236. 455. 626. 723. 769. 866.

20 53.5 86.7 101. 137. 262. 363. 450. 493. 524.

25 44.2 70.9 88.4 107. 198. 301. 369. 402. 440.

30 35.2 62.1 76.3 85.2 161. 239. 309. 328. 369.

40 21.2 37.3 52.2 63.9 124. 181. 220. 242. 290.

50 16.5 26.9 34.9 49.0 88.4 136. 165. 187. 217.

60 15.4 21.3 27.9 35.5 60.1 104. 123. 138. 179.

70 14.4 18.9 22.9 28.4 45.5 77.9 93.3 109. 149.

75 13.9 15.3 21.2 25.1 38.4 66.4 77.3 92.1 131.

80 13.0 13.9 19.4 22.8 34.9 55.0 65.3 84.6 122.

90 10.3 12.7 14.4 17.7 28.1 39.3 47.0 68.4 101.

95 9.00 10.3 11.9 14.4 24.2 34.4 41.1 61.6 84.9

98 7.97 8.79 11.1 13.8 22.1 30.2 38.3 57.9 64.4

99 7.14 8.20 10.5 13.0 21.7 29.3 35.5 54.1 60.7
74 Methods for Estimating Selected Low-Flow Statistics and Development of Annual Flow-Duration Statistics for Ohio

03265000 Stillwater River at Pleasant Hill, Ohio

Years analyzed = 85

Climatic year range = 1917–2008

[APEE, annual percentage equaled or exceeded; ft3/s, cubic foot per second]

Daily mean streamflow (ft3/s) that was equaled or exceeded the indicated percentage of time at APEE level

APEE 98 95 90 80 50 20 10 5 2

1 1180. 2460. 3000. 3820. 5500. 6590. 8100. 9890. 12100.

2 712. 1380. 1840. 2400. 3810. 5120. 6270. 7040. 8020.

5 457. 648. 847. 1190. 1940. 2870. 3310. 3560. 3800.

10 288. 330. 456. 554. 1040. 1450. 1730. 2090. 2180.

20 151. 167. 200. 267. 544. 713. 899. 1030. 1100.

25 120. 140. 169. 206. 404. 567. 694. 781. 846.

30 89.6 110. 145. 167. 329. 451. 538. 609. 680.

40 48.4 72.0 90.2 112. 224. 323. 366. 423. 479.

50 36.9 47.8 63.0 86.2 152. 228. 267. 328. 353.

60 26.3 34.9 47.2 65.3 106. 171. 209. 236. 289.

70 21.4 29.3 37.9 48.2 76.6 126. 164. 182. 232.

75 20.2 25.9 34.2 39.2 67.8 108. 142. 157. 210.

80 18.6 24.0 29.1 34.6 57.2 91.3 113. 141. 190.

90 12.9 17.3 19.0 24.1 42.0 62.2 80.2 107. 149.

95 10.8 12.5 14.2 18.0 34.0 56.0 66.8 85.8 125.

98 8.72 9.46 10.9 14.5 28.0 44.8 55.0 79.0 99.0

99 7.63 8.76 9.98 12.2 27.3 42.8 53.5 73.6 86.2

7-day mean streamflow (ft3/s) that was equaled or exceeded the indicated percentage of time at APEE level

APEE 98 95 90 80 50 20 10 5 2

1 943. 1260. 1650. 2350. 3790. 4870. 5250. 6040. 8040.

2 773. 1040. 1240. 2020. 2680. 3670. 4150. 4830. 6590.

5 402. 630. 932. 1260. 1830. 2620. 2880. 3510. 3940.

10 305. 361. 475. 666. 1220. 1700. 1950. 2210. 2450.

20 149. 180. 221. 327. 656. 931. 1160. 1310. 1410.

25 111. 140. 185. 233. 486. 735. 902. 1070. 1080.

30 93.8 118. 147. 188. 402. 585. 720. 874. 962.

40 48.0 73.1 96.5 128. 260. 408. 519. 596. 709.

50 34.5 46.9 64.3 90.7 170. 287. 340. 421. 457.

60 25.2 35.9 47.9 66.4 116. 203. 245. 290. 349.

70 21.7 30.3 37.2 48.8 84.3 153. 186. 217. 273.

75 20.7 26.1 33.6 41.0 70.0 124. 159. 177. 240.

80 18.7 24.8 27.9 36.1 57.9 100. 128. 161. 222.

90 15.1 18.7 20.6 24.9 44.3 69.6 91.4 111. 175.

95 12.7 15.4 16.7 20.3 37.0 60.5 71.6 92.5 153.

98 9.73 11.1 14.1 16.7 32.1 49.9 59.5 85.0 122.

99 8.65 9.71 12.8 16.3 30.0 47.3 56.1 81.5 97.7
Appendix 3 75

03266500 Mad River at Zanesfield, Ohio

Years analyzed = 32

Climatic year range = 1947–78

[APEE, annual percentage equaled or exceeded; ft3/s, cubic foot per second]

Daily mean streamflow (ft3/s) that was equaled or exceeded the indicated percentage of time at APEE level

APEE 95 90 80 70 50 30 20 10 5

1 28.1 43.0 45.3 60.0 70.2 88.5 95.1 106. 127.

2 22.6 31.5 34.4 37.8 45.3 59.2 65.9 70.6 82.6

5 11.1 12.6 15.9 17.9 24.0 30.2 35.0 45.0 52.9

10 6.36 7.72 9.54 12.2 15.0 19.5 20.4 22.8 28.8

20 4.13 4.51 5.64 7.00 9.54 10.3 14.0 14.7 16.7

25 3.36 3.67 4.78 5.66 7.57 9.56 12.4 13.0 14.4

30 2.52 2.93 3.84 4.79 6.30 8.22 11.0 12.0 13.0

40 1.83 2.10 2.58 3.49 4.70 6.71 8.57 9.41 10.3

50 1.43 1.53 1.86 2.58 3.60 5.10 5.74 6.72 7.89

60 1.23 1.30 1.56 1.92 2.75 3.37 4.30 5.07 6.16

70 0.96 1.10 1.26 1.77 2.09 2.62 3.18 4.10 4.96

75 0.88 1.03 1.26 1.59 1.80 2.31 2.68 3.78 4.68

80 0.84 1.00 1.11 1.49 1.60 2.20 2.42 3.39 4.23

90 0.79 0.83 1.00 1.19 1.40 1.90 2.04 2.76 3.37

95 0.71 0.80 0.90 1.10 1.30 1.80 1.96 2.35 2.87

98 0.67 0.73 0.87 1.00 1.20 1.61 1.80 1.92 2.74

99 0.64 0.73 0.82 0.90 1.15 1.51 1.76 1.88 2.58

7-day mean streamflow (ft3/s) that was equaled or exceeded the indicated percentage of time at APEE level

APEE 95 90 80 70 50 30 20 10 5

1 19.7 27.9 30.5 34.4 44.8 57.2 61.7 72.4 101.

2 14.2 20.4 26.6 28.5 32.2 42.3 44.5 55.4 63.3

5 11.1 16.6 18.6 20.0 25.0 29.8 33.4 42.2 46.5

10 6.34 6.80 11.0 13.6 15.5 19.7 24.7 27.8 31.5

20 4.18 4.74 5.98 7.84 10.5 13.1 16.0 19.0 22.0

25 3.54 4.05 5.18 6.22 8.90 10.9 14.2 15.9 18.7

30 2.63 3.29 3.94 5.21 7.66 9.15 12.2 13.5 15.5

40 1.82 2.16 2.49 3.92 5.10 7.23 9.16 10.1 12.2

50 1.45 1.61 1.97 2.60 3.91 5.51 6.43 7.03 9.02

60 1.19 1.32 1.66 2.06 2.76 3.56 4.89 5.63 7.10

70 0.98 1.15 1.33 1.73 2.19 2.80 3.39 4.52 5.50

75 0.94 1.09 1.25 1.64 1.96 2.48 2.98 3.99 5.02

80 0.87 1.03 1.19 1.52 1.67 2.21 2.63 3.57 4.50

90 0.79 0.89 1.07 1.22 1.46 1.93 2.13 2.98 3.63

95 0.73 0.82 0.94 1.13 1.31 1.87 2.01 2.54 3.06

98 0.69 0.79 0.90 1.04 1.24 1.78 1.86 2.06 2.84

99 0.64 0.72 0.86 0.99 1.21 1.68 1.80 2.03 2.80
76 Methods for Estimating Selected Low-Flow Statistics and Development of Annual Flow-Duration Statistics for Ohio

03267000 Mad River near Urbana, Ohio

Years analyzed = 69

Climatic year range = 1926–2008

[APEE, annual percentage equaled or exceeded; ft3/s, cubic foot per second]

Daily mean streamflow (ft3/s) that was equaled or exceeded the indicated percentage of time at APEE level

APEE 98 95 90 80 50 20 10 5 2

1 233. 315. 410. 488. 808. 1260. 1440. 1520. 2100.

2 201. 233. 259. 353. 550. 792. 941. 1090. 1150.

5 155. 160. 178. 233. 345. 497. 579. 629. 666.

10 111. 121. 139. 164. 241. 362. 409. 444. 468.

20 79.4 88.0 107. 127. 183. 275. 298. 309. 326.

25 68.0 82.3 94.0 113. 173. 240. 267. 288. 295.

30 58.0 74.5 85.0 98.8 158. 219. 246. 265. 271.

40 48.9 61.8 71.0 79.0 137. 184. 207. 231. 245.

50 42.6 53.0 58.0 70.5 120. 160. 182. 197. 221.

60 37.6 46.5 52.0 62.0 104. 139. 164. 171. 202.

70 35.3 44.0 46.8 57.0 90.0 121. 144. 153. 189.

75 34.8 43.0 44.0 54.5 81.0 117. 133. 144. 181.

80 33.8 41.2 43.0 52.0 78.0 106. 123. 134. 173.

90 32.6 38.6 40.0 44.6 70.0 98.7 106. 122. 154.

95 30.4 35.3 37.3 41.0 67.0 90.0 98.3 116. 149.

98 26.0 33.2 35.0 39.0 62.7 85.0 95.3 108. 141.

99 25.4 31.5 34.7 39.0 60.7 83.0 94.0 103. 138.

7-day mean streamflow (ft3/s) that was equaled or exceeded the indicated percentage of time at APEE level

APEE 98 95 90 80 50 20 10 5 2

1 182. 204. 289. 410. 562. 885. 1020. 1230. 1540.

2 171. 191. 246. 338. 466. 647. 775. 877. 1160.

5 143. 167. 183. 241. 350. 514. 599. 660. 759.

10 107. 120. 140. 177. 274. 397. 438. 449. 500.

20 75.9 91.1 106. 130. 199. 288. 314. 336. 351.

25 67.4 84.7 95.0 115. 180. 257. 295. 306. 323.

30 56.9 77.9 86.6 101. 170. 236. 265. 278. 292.

40 50.0 63.8 72.1 80.7 140. 195. 221. 238. 260.

50 42.2 53.7 58.0 70.0 126. 166. 189. 210. 234.

60 37.4 46.9 52.9 62.9 106. 148. 167. 180. 211.

70 35.7 44.6 46.9 56.7 91.0 130. 149. 159. 199.

75 34.9 43.1 45.3 54.6 83.1 119. 137. 149. 189.

80 34.1 41.8 43.4 52.4 79.0 109. 125. 138. 182.

90 33.0 39.1 40.3 44.9 70.5 100. 107. 123. 161.

95 31.1 36.6 38.3 42.1 67.4 93.7 101. 118. 154.

98 26.3 33.9 36.3 40.0 64.0 88.7 97.7 112. 148.

99 25.9 32.4 36.0 38.9 62.3 87.0 97.3 105. 144.
Appendix 3 77

03270800 Wolf Creek at Trotwood, Ohio

Years analyzed = 23

Climatic year range = 1963–85

[APEE, annual percentage equaled or exceeded; ft3/s, cubic foot per second]

Daily mean streamflow (ft3/s) that was equaled or exceeded the indicated percentage of time at APEE level

APEE 95 90 80 70 50 30 20 10 5

1 115. 161. 223. 243. 307. 386. 441. 460. 463.

2 51.4 82.1 128. 157. 205. 222. 261. 349. 378.

5 28.9 40.8 70.2 77.8 107. 126. 136. 154. 177.

10 15.6 20.3 31.2 44.2 50.2 64.8 75.9 85.3 87.0

20 6.50 8.62 15.4 18.8 22.8 31.5 36.6 38.6 40.3

25 4.52 6.86 11.6 12.6 18.5 23.8 29.1 30.8 31.0

30 3.34 5.78 8.88 10.5 15.0 19.6 24.9 25.2 25.8

40 2.00 3.26 5.54 7.04 11.0 12.8 17.1 18.6 19.8

50 0.94 1.78 3.88 4.92 8.30 9.36 11.4 13.0 14.6

60 0.57 1.07 1.96 3.71 5.60 6.68 8.39 9.71 10.8

70 0.42 0.53 1.16 2.32 3.40 4.58 5.13 6.17 8.20

75 0.40 0.45 0.96 1.80 2.90 3.79 3.90 5.00 7.40

80 0.32 0.43 0.70 1.32 2.10 2.68 3.20 3.74 6.33

90 0.22 0.32 0.37 0.63 1.10 1.27 1.52 2.20 4.60

95 0.11 0.17 0.29 0.35 0.70 0.89 1.01 1.86 3.48

98 0.01 0.07 0.20 0.25 0.46 0.70 0.84 1.62 2.33

99 0.00 0.03 0.18 0.21 0.41 0.69 0.83 1.55 1.86

7-day mean streamflow (ft3/s) that was equaled or exceeded the indicated percentage of time at APEE level

APEE 95 90 80 70 50 30 20 10 5

1 64.5 85.2 139. 153. 193. 228. 258. 275. 304.

2 53.8 70.5 110. 126. 136. 182. 194. 204. 228.

5 33.3 51.4 66.9 85.3 97.7 114. 121. 142. 154.

10 19.9 23.8 41.1 52.5 65.0 73.5 78.0 102. 108.

20 5.90 9.39 19.9 26.5 31.6 40.2 55.8 58.3 58.7

25 4.22 6.75 15.2 17.1 25.3 31.4 41.2 46.0 47.3

30 3.23 5.86 10.7 12.7 19.0 27.7 31.8 38.6 39.1

40 2.17 3.45 6.14 8.69 13.7 16.9 22.1 23.7 27.7

50 1.24 2.16 4.22 5.37 9.24 11.2 14.5 16.1 17.9

60 0.71 1.42 2.40 3.85 5.91 7.47 10.3 12.5 13.5

70 0.50 0.62 1.50 2.55 3.95 5.34 6.08 7.87 10.3

75 0.39 0.50 1.16 2.11 3.39 4.10 4.81 6.25 9.13

80 0.29 0.47 0.95 1.51 2.66 3.10 4.05 4.68 7.85

90 0.19 0.35 0.43 0.67 1.24 1.49 1.86 2.53 5.59

95 0.12 0.24 0.31 0.46 0.87 1.07 1.26 2.07 4.43

98 0.06 0.18 0.28 0.41 0.65 0.87 0.95 1.90 3.15

99 0.02 0.10 0.21 0.30 0.59 0.80 0.87 1.78 2.80
78 Methods for Estimating Selected Low-Flow Statistics and Development of Annual Flow-Duration Statistics for Ohio

03271000 Wolf Creek at Dayton, Ohio

Years analyzed = 26

Climatic year range = 1939–2008

[APEE, annual percentage equaled or exceeded; ft3/s, cubic foot per second]

Daily mean streamflow (ft3/s) that was equaled or exceeded the indicated percentage of time at APEE level

APEE 95 90 80 70 50 30 20 10 5

1 380. 417. 510. 599. 786. 1180. 1280. 1510. 1630.

2 223. 238. 305. 385. 489. 675. 787. 947. 1070.

5 98.1 114. 131. 197. 245. 324. 394. 436. 506.

10 53.4 59.3 72.7 95.2 129. 164. 207. 233. 268.

20 31.6 34.2 37.9 45.5 72.0 89.2 107. 116. 124.

25 24.0 26.8 30.2 38.5 59.3 72.0 82.2 92.4 99.6

30 18.4 23.0 25.3 32.6 49.1 58.0 65.3 77.9 82.4

40 7.15 13.1 18.2 23.3 32.0 44.4 49.2 62.0 63.7

50 5.01 8.57 13.8 17.0 21.5 33.0 38.2 49.3 51.9

60 3.95 6.89 10.0 13.0 14.7 24.9 26.6 40.3 42.7

70 3.51 5.55 6.80 9.82 12.0 16.9 20.6 30.3 34.6

75 3.28 5.05 5.52 8.17 11.5 14.9 18.6 25.5 30.8

80 2.91 4.40 4.54 7.26 10.0 13.0 16.0 22.8 27.6

90 2.09 3.15 3.53 5.90 7.69 9.99 12.0 16.9 20.1

95 1.59 2.28 2.82 5.15 6.35 8.83 10.5 14.0 16.2

98 1.34 1.75 2.30 3.43 5.17 7.90 9.57 11.1 14.4

99 1.24 1.35 2.16 3.40 5.00 7.66 8.67 10.7 12.8

7-day mean streamflow (ft3/s) that was equaled or exceeded the indicated percentage of time at APEE level

APEE 95 90 80 70 50 30 20 10 5

1 215. 247. 366. 389. 502. 604. 731. 883. 1050.

2 165. 221. 260. 314. 345. 517. 529. 614. 752.

5 129. 146. 163. 185. 240. 363. 384. 447. 547.

10 71.0 79.5 96.4 129. 161. 228. 245. 284. 328.

20 33.5 37.3 46.0 53.7 94.6 116. 136. 155. 181.

25 25.2 31.5 37.3 41.9 77.4 89.3 99.6 122. 152.

30 20.1 25.8 28.8 36.1 60.1 73.5 80.4 107. 135.

40 7.22 14.5 20.8 26.2 38.8 53.9 58.8 76.3 82.8

50 4.79 9.93 15.2 20.7 27.5 40.1 46.8 57.8 62.9

60 4.02 7.25 10.7 14.4 17.0 31.5 34.1 48.8 55.3

70 3.53 5.72 6.89 11.2 14.0 21.4 25.2 36.8 45.8

75 3.25 5.21 5.92 9.17 12.6 17.9 22.9 33.4 40.4

80 2.94 4.41 4.80 7.98 11.5 14.9 19.9 28.7 35.5

90 2.16 3.20 3.76 6.02 8.18 11.1 13.8 20.4 23.9

95 1.75 2.54 3.03 5.40 6.88 9.31 12.5 18.0 19.5

98 1.54 1.81 2.50 3.69 5.94 8.60 10.4 13.5 16.5

99 1.42 1.60 2.19 3.57 5.40 8.38 9.73 11.4 15.0
Appendix 3 79

03271800 Twin Creek near Ingomar, Ohio

Years analyzed = 36

Climatic year range = 1963–98

[APEE, annual percentage equaled or exceeded; ft3/s, cubic foot per second]

Daily mean streamflow (ft3/s) that was equaled or exceeded the indicated percentage of time at APEE level

APEE 95 90 80 70 50 30 20 10 5

1 930. 1110. 1910. 2110. 2490. 2880. 3580. 4070. 4130.

2 434. 719. 943. 1360. 1710. 2050. 2330. 2470. 2700.

5 239. 310. 501. 654. 897. 1060. 1160. 1350. 1470.

10 143. 190. 270. 325. 421. 534. 592. 766. 862.

20 59.7 91.4 135. 154. 202. 264. 303. 366. 418.

25 48.4 74.4 102. 118. 162. 204. 231. 296. 341.

30 37.8 61.6 81.0 97.5 136. 167. 192. 230. 266.

40 20.4 38.6 52.0 67.4 98.5 110. 135. 163. 184.

50 12.9 25.6 35.2 41.1 71.5 82.7 89.6 106. 126.

60 9.32 13.4 20.6 24.2 48.2 60.6 65.0 75.5 106.

70 7.00 8.12 12.8 17.1 29.8 35.9 44.2 53.2 79.3

75 6.08 6.94 11.4 15.1 23.8 29.5 33.2 45.7 68.1

80 5.76 6.41 9.88 12.1 19.0 22.1 26.9 37.8 56.2

90 4.09 4.63 6.14 8.03 11.5 16.0 18.6 24.0 33.4

95 3.46 3.97 5.24 6.55 9.55 14.0 15.6 20.5 27.6

98 2.99 3.54 4.72 5.93 8.45 12.3 13.2 18.1 21.0

99 2.87 3.37 4.63 5.57 7.65 11.0 12.9 15.8 19.3

7-day mean streamflow (ft3/s) that was equaled or exceeded the indicated percentage of time at APEE level

APEE 95 90 80 70 50 30 20 10 5

1 567. 672. 1040. 1310. 1540. 1900. 2180. 2290. 2690.

2 477. 591. 841. 984. 1160. 1350. 1490. 1760. 1970.

5 291. 373. 611. 734. 856. 962. 1040. 1230. 1330.

10 150. 191. 326. 443. 535. 643. 724. 851. 890.

20 65.4 98.3 172. 202. 278. 383. 410. 492. 557.

25 50.7 79.2 122. 158. 204. 290. 311. 402. 456.

30 40.5 65.7 90.0 117. 167. 220. 250. 329. 386.

40 20.3 40.5 56.1 74.0 119. 144. 176. 230. 252.

50 12.9 26.9 36.5 45.2 82.1 99.4 105. 148. 157.

60 9.56 12.4 22.1 25.1 52.2 69.1 77.3 84.3 125.

70 6.94 8.10 13.3 18.4 34.3 42.0 51.1 62.3 96.0

75 6.25 6.81 10.9 15.2 26.2 32.3 37.0 53.1 81.7

80 5.71 6.35 10.1 13.1 19.3 24.8 28.8 41.2 70.7

90 3.95 4.75 6.39 8.33 12.0 17.1 19.2 24.7 36.7

95 3.44 4.01 5.53 6.96 10.1 14.7 16.5 21.4 31.4

98 3.21 3.65 4.94 6.38 9.11 12.9 14.5 20.1 24.3

99 3.09 3.42 4.91 5.76 8.63 12.1 13.8 18.2 21.2
80 Methods for Estimating Selected Low-Flow Statistics and Development of Annual Flow-Duration Statistics for Ohio

03272700 Sevenmile Creek at Camden, Ohio

Years analyzed = 35

Climatic year range = 1971–2008

[APEE, annual percentage equaled or exceeded; ft3/s, cubic foot per second]

Daily mean streamflow (ft3/s) that was equaled or exceeded the indicated percentage of time at APEE level

APEE 95 90 80 70 50 30 20 10 5

1 389. 433. 570. 652. 844. 1060. 1290. 1510. 1730.

2 216. 250. 304. 450. 570. 672. 769. 952. 1060.

5 102. 123. 162. 241. 294. 356. 401. 480. 511.

10 65.5 73.4 101. 121. 170. 198. 213. 284. 293.

20 29.8 40.6 50.4 62.9 83.4 109. 112. 141. 164.

25 23.4 32.9 42.0 50.2 68.0 83.3 95.3 113. 132.

30 19.3 27.1 35.2 41.6 56.9 66.7 79.2 96.3 108.

40 12.4 16.4 22.9 31.8 41.6 49.1 57.8 69.4 74.2

50 7.82 10.6 15.2 21.9 29.0 36.2 42.6 51.6 58.6

60 5.02 5.79 7.39 10.7 20.0 24.5 29.9 40.0 47.2

70 3.76 3.96 4.42 7.40 12.0 16.0 19.0 33.8 40.2

75 3.10 3.31 3.88 5.91 9.00 11.0 15.0 30.8 35.2

80 2.50 2.96 3.56 4.74 7.04 9.37 12.8 25.2 28.8

90 1.86 1.99 2.61 3.04 4.92 6.30 7.15 17.4 18.7

95 1.56 1.70 2.10 2.61 3.70 5.17 6.28 13.2 15.0

98 1.27 1.57 1.77 2.08 3.10 4.78 5.17 11.1 12.5

99 1.20 1.49 1.67 1.85 2.97 4.43 4.90 10.0 12.0

7-day mean streamflow (ft3/s) that was equaled or exceeded the indicated percentage of time at APEE level

APEE 95 90 80 70 50 30 20 10 5

1 224. 293. 341. 427. 515. 670. 723. 1080. 1400.

2 209. 239. 266. 313. 388. 515. 611. 664. 856.

5 133. 151. 171. 218. 292. 360. 387. 456. 525.

10 69.3 83.0 107. 156. 178. 239. 260. 301. 327.

20 31.9 46.4 66.7 72.8 107. 131. 143. 182. 252.

25 24.0 39.1 49.0 59.0 82.8 104. 111. 154. 202.

30 20.1 30.7 38.5 46.2 64.4 88.5 91.5 135. 151.

40 14.1 16.7 23.8 35.8 46.9 60.8 69.1 93.7 105.

50 9.74 11.2 16.4 22.8 32.9 41.5 47.3 62.8 79.9

60 5.30 6.36 8.10 11.4 20.8 27.3 32.4 50.4 57.7

70 4.08 4.34 4.78 8.48 12.5 16.9 20.7 41.1 50.5

75 3.51 3.60 4.04 6.74 9.99 13.9 17.2 37.8 43.0

80 3.01 3.16 3.81 4.93 8.36 11.1 13.9 31.9 38.8

90 2.02 2.21 2.77 3.34 5.63 6.65 7.91 20.6 21.2

95 1.61 1.84 2.33 2.74 4.03 5.41 6.95 16.1 17.4

98 1.42 1.65 2.01 2.30 3.26 5.05 6.18 12.2 14.3

99 1.33 1.59 1.81 2.14 3.14 4.73 5.73 10.9 13.3
Appendix 3 81

04177000 Ottawa River at University of Toledo, Toledo, Ohio

Years analyzed = 35

Climatic year range = 1945–2008

[APEE, annual percentage equaled or exceeded; ft3/s, cubic foot per second]

Daily mean streamflow (ft3/s) that was equaled or exceeded the indicated percentage of time at APEE level

APEE 95 90 80 70 50 30 20 10 5

1 461. 831. 994. 1110. 1250. 1610. 1730. 2090. 2350.

2 408. 555. 741. 789. 908. 1230. 1470. 1600. 1910.

5 243. 302. 422. 460. 550. 772. 832. 980. 1040.

10 122. 150. 226. 250. 310. 398. 472. 525. 590.

20 47.1 72.1 106. 111. 158. 179. 200. 231. 285.

25 35.5 55.9 75.5 90.1 119. 131. 151. 180. 210.

30 28.8 46.3 53.6 69.6 92.6 100. 115. 139. 164.

40 17.2 30.6 38.2 44.6 61.0 67.8 75.2 97.6 105.

50 10.5 19.4 25.6 30.0 45.0 49.0 55.0 69.4 73.2

60 7.43 13.8 19.4 22.4 32.0 37.2 40.6 53.4 57.2

70 5.48 9.83 14.2 15.0 18.0 27.2 30.8 38.2 48.6

75 4.60 7.45 11.1 12.0 15.0 22.2 25.0 32.6 44.6

80 3.90 5.72 8.73 9.68 12.0 17.7 21.8 28.3 39.8

90 0.82 3.48 4.33 5.44 8.70 11.2 13.9 20.2 27.7

95 0.00 2.22 2.94 4.30 7.03 8.98 10.8 16.5 20.0

98 0.00 0.95 2.45 3.66 5.76 7.43 9.39 13.5 16.6

99 0.00 0.69 2.10 2.94 5.16 7.12 9.23 12.4 15.6

7-day mean streamflow (ft3/s) that was equaled or exceeded the indicated percentage of time at APEE level

APEE 95 90 80 70 50 30 20 10 5

1 324. 525. 587. 703. 860. 1050. 1140. 1480. 1730.

2 274. 446. 551. 609. 683. 861. 978. 1240. 1360.

5 206. 310. 377. 428. 477. 646. 736. 859. 1020.

10 151. 182. 235. 277. 319. 447. 482. 551. 583.

20 61.8 72.2 120. 149. 182. 228. 258. 325. 349.

25 39.1 59.3 86.7 112. 138. 172. 186. 230. 287.

30 25.9 48.6 60.7 84.3 109. 133. 152. 190. 230.

40 17.2 30.8 40.4 52.0 73.1 84.8 94.1 129. 158.

50 11.9 21.5 29.9 32.9 49.4 61.0 70.1 89.7 101.

60 9.44 15.2 21.3 23.3 35.0 42.3 48.6 65.3 67.8

70 7.51 11.8 16.3 17.7 22.8 31.4 34.7 47.1 55.2

75 6.24 9.86 12.6 14.4 18.6 26.1 29.4 38.5 50.1

80 4.31 6.92 9.54 12.1 15.0 20.6 25.6 32.8 45.1

90 1.28 4.96 5.97 7.22 9.86 12.9 17.6 24.5 35.6

95 0.05 2.89 4.04 5.24 7.81 10.6 14.2 20.9 29.4

98 0.01 1.80 3.07 4.11 6.90 9.07 12.0 17.6 21.9

99 0.00 1.30 2.96 3.91 6.24 8.68 9.61 16.1 19.1
82 Methods for Estimating Selected Low-Flow Statistics and Development of Annual Flow-Duration Statistics for Ohio

04184500 Bean Creek at Powers, Ohio

Years analyzed = 48

Climatic year range = 1941–2008

[APEE, annual percentage equaled or exceeded; ft3/s, cubic foot per second]

Daily mean streamflow (ft3/s) that was equaled or exceeded the indicated percentage of time at APEE level

APEE 95 90 80 70 50 30 20 10 5

1 701. 777. 978. 1110. 1350. 1750. 2110. 2380. 2720.

2 478. 536. 731. 784. 1060. 1310. 1470. 1800. 1990.

5 254. 302. 452. 497. 686. 844. 998. 1160. 1210.

10 159. 193. 263. 338. 430. 523. 608. 700. 756.

20 71.0 110. 139. 182. 241. 295. 316. 387. 408.

25 53.0 89.6 113. 139. 195. 240. 259. 302. 332.

30 43.9 64.9 81.8 112. 161. 186. 219. 239. 266.

40 25.8 36.5 47.4 67.0 111. 132. 146. 178. 185.

50 20.4 23.0 37.0 47.5 74.0 94.6 106. 132. 145.

60 15.4 19.7 26.8 36.7 53.2 70.6 78.6 98.0 112.

70 13.4 17.7 22.0 25.7 38.5 49.5 54.0 63.8 87.4

75 12.9 14.9 19.0 22.7 32.5 41.0 46.0 57.5 75.8

80 11.0 13.9 17.8 20.1 27.6 35.0 38.6 45.5 63.8

90 8.66 10.0 14.0 15.7 20.0 24.3 28.4 35.1 39.5

95 6.85 8.33 11.0 13.0 16.0 20.3 23.1 30.0 31.7

98 6.38 7.19 9.82 11.7 14.0 18.5 20.1 26.1 28.5

99 5.97 6.78 9.18 10.5 13.0 17.2 20.0 25.1 27.5

7-day mean streamflow (ft3/s) that was equaled or exceeded the indicated percentage of time at APEE level

APEE 95 90 80 70 50 30 20 10 5

1 519. 642. 741. 890. 1040. 1330. 1520. 1750. 1840.

2 356. 518. 609. 683. 852. 1040. 1260. 1510. 1590.

5 227. 281. 430. 492. 626. 787. 947. 1060. 1190.

10 155. 168. 302. 344. 425. 553. 611. 756. 789.

20 65.2 118. 147. 200. 266. 317. 351. 435. 482.

25 52.7 98.2 112. 161. 211. 263. 292. 343. 395.

30 41.9 60.9 81.5 122. 171. 202. 247. 274. 303.

40 24.0 35.8 48.9 68.4 119. 147. 163. 203. 216.

50 20.3 24.5 38.7 49.9 75.1 104. 115. 148. 161.

60 16.0 19.2 27.3 36.0 51.9 74.8 84.2 104. 131.

70 13.3 17.7 23.1 27.0 39.6 50.7 56.0 69.9 103.

75 12.5 14.7 19.7 23.0 33.9 42.8 47.7 59.6 86.8

80 11.0 13.9 17.8 20.4 28.3 37.1 41.6 48.6 70.7

90 8.78 10.5 14.5 16.5 20.6 25.5 29.7 36.7 41.5

95 7.11 8.73 11.7 14.1 16.4 20.5 25.1 30.8 34.5

98 6.72 7.33 10.8 12.2 14.5 18.9 21.6 27.2 30.2

99 6.68 7.02 10.2 11.7 13.6 18.6 20.8 26.2 29.1
Appendix 3 83

04185440 Unnamed Tributary to Lost Creek near Farmer, Ohio

Years analyzed = 20

Climatic year range = 1986–2008

[APEE, annual percentage equaled or exceeded; ft3/s, cubic foot per second]

Daily mean streamflow (ft3/s) that was equaled or exceeded the indicated percentage of time at APEE level

APEE 95 90 80 70 50 30 20 10 5

1 32.1 41.2 50.2 58.3 74.4 88.0 101. 136. 149.

2 17.4 25.9 28.3 36.8 46.1 56.5 63.5 66.9 83.8

5 8.33 9.76 15.5 15.9 18.3 27.1 28.3 32.0 33.9

10 3.43 4.04 5.69 6.87 8.97 11.3 12.0 13.7 14.0

20 1.11 1.33 2.27 2.65 3.48 4.19 4.72 5.43 5.93

25 0.80 0.89 1.66 1.76 2.28 3.14 3.25 4.10 4.25

30 0.46 0.59 1.12 1.33 1.65 2.27 2.66 3.11 3.50

40 0.26 0.36 0.65 0.71 0.99 1.49 1.76 1.98 2.09

50 0.12 0.20 0.34 0.38 0.70 0.89 1.10 1.37 1.49

60 0.09 0.10 0.15 0.21 0.46 0.57 0.70 0.95 1.09

70 0.05 0.06 0.09 0.13 0.23 0.40 0.46 0.67 0.70

75 0.02 0.05 0.07 0.09 0.18 0.35 0.40 0.55 0.60

80 0.00 0.04 0.05 0.06 0.12 0.28 0.31 0.46 0.50

90 0.00 0.00 0.02 0.03 0.07 0.12 0.16 0.28 0.30

95 0.00 0.00 0.00 0.01 0.04 0.08 0.09 0.19 0.25

98 0.00 0.00 0.00 0.00 0.03 0.06 0.08 0.13 0.21

99 0.00 0.00 0.00 0.00 0.02 0.05 0.07 0.11 0.17

7-day mean streamflow (ft3/s) that was equaled or exceeded the indicated percentage of time at APEE level

APEE 95 90 80 70 50 30 20 10 5

1 19.3 21.2 26.2 31.0 35.5 42.5 48.0 59.7 67.1

2 14.3 16.8 19.5 22.0 27.3 30.3 32.1 41.8 51.2

5 9.16 10.6 14.0 16.3 20.5 25.2 26.3 34.4 35.0

10 4.78 6.92 8.14 10.6 12.8 15.8 16.8 17.2 19.5

20 1.65 2.09 4.19 4.84 6.30 9.04 10.2 10.9 11.1

25 1.32 1.54 3.00 3.48 4.84 6.52 7.33 8.87 9.94

30 0.90 1.10 1.97 2.59 3.47 4.48 5.38 6.41 8.13

40 0.38 0.48 0.97 1.27 1.85 2.54 3.33 3.94 4.28

50 0.15 0.28 0.49 0.62 1.04 1.29 1.98 2.64 3.36

60 0.11 0.12 0.19 0.25 0.60 0.77 1.01 1.68 1.86

70 0.06 0.08 0.09 0.15 0.30 0.54 0.64 0.94 1.02

75 0.05 0.05 0.07 0.11 0.25 0.44 0.50 0.73 0.77

80 0.03 0.04 0.05 0.08 0.18 0.35 0.42 0.58 0.62

90 0.00 0.01 0.02 0.03 0.09 0.14 0.22 0.37 0.41

95 0.00 0.00 0.01 0.02 0.06 0.09 0.14 0.24 0.31

98 0.00 0.00 0.00 0.00 0.04 0.08 0.10 0.16 0.28

99 0.00 0.00 0.00 0.00 0.03 0.07 0.08 0.13 0.27
84 Methods for Estimating Selected Low-Flow Statistics and Development of Annual Flow-Duration Statistics for Ohio

04189000 Blanchard River near Findlay, Ohio

Years analyzed = 79

Climatic year range = 1924–2008

[APEE, annual percentage equaled or exceeded; ft3/s, cubic foot per second]

Daily mean streamflow (ft3/s) that was equaled or exceeded the indicated percentage of time at APEE level

APEE 98 95 90 80 50 20 10 5 2

1 626. 941. 1430. 1900. 3320. 4330. 5570. 6180. 8210.

2 484. 791. 1070. 1340. 2350. 3240. 3820. 4900. 5620.

5 236. 332. 552. 753. 1170. 1960. 2380. 2860. 3350.

10 128. 163. 216. 346. 574. 1060. 1330. 1650. 1740.

20 46.0 64.4 93.6 126. 253. 476. 539. 659. 874.

25 33.8 54.0 67.0 91.5 185. 346. 405. 471. 615.

30 25.3 47.2 55.0 71.0 150. 257. 323. 394. 475.

40 11.8 17.2 36.6 44.0 96.0 175. 221. 241. 309.

50 7.44 11.0 21.0 30.0 64.0 120. 157. 172. 204.

60 5.36 9.50 13.0 22.0 45.0 75.0 95.0 125. 157.

70 4.44 7.50 9.00 15.8 30.0 54.1 71.8 90.1 126.

75 3.70 6.50 8.20 12.0 26.0 44.8 66.0 77.0 112.

80 2.87 3.90 7.40 11.0 22.4 38.0 55.0 65.0 102.

90 1.80 3.20 5.40 7.40 15.4 24.6 40.0 46.6 74.8

95 1.30 2.80 4.40 5.80 12.0 21.3 30.3 38.0 60.3

98 1.14 2.20 3.30 4.30 10.0 18.0 24.3 33.3 48.2

99 0.95 1.80 2.90 4.13 9.00 17.0 23.0 30.3 41.7

7-day mean streamflow (ft3/s) that was equaled or exceeded the indicated percentage of time at APEE level

APEE 98 95 90 80 50 20 10 5 2

1 372. 711. 922. 1270. 2170. 2990. 3560. 4100. 4730.

2 350. 583. 812. 1050. 1650. 2260. 3130. 3730. 3980.

5 223. 347. 550. 720. 1210. 1620. 2200. 2510. 2710.

10 106. 165. 245. 407. 752. 1160. 1440. 1520. 1740.

20 48.5 72.6 105. 169. 305. 644. 791. 909. 1030.

25 37.0 60.7 73.3 118. 228. 446. 584. 773. 892.

30 26.8 52.9 57.6 79.4 182. 364. 460. 580. 704.

40 13.5 17.9 39.9 50.9 115. 220. 275. 343. 496.

50 7.05 11.4 21.8 32.6 76.0 137. 183. 232. 297.

60 5.29 9.71 12.7 24.1 51.7 96.7 123. 153. 207.

70 4.60 7.37 9.77 16.6 32.9 63.9 79.4 119. 159.

75 4.01 5.10 8.03 14.0 27.9 50.1 75.3 105. 141.

80 3.23 4.50 7.50 11.9 24.3 44.4 65.3 84.7 128.

90 2.28 3.50 6.33 7.86 17.9 26.7 44.0 53.6 94.1

95 1.74 3.01 4.73 6.26 13.3 22.0 34.4 43.0 73.8

98 1.52 2.46 4.09 5.37 11.1 19.6 26.3 40.4 59.1

99 1.35 2.21 3.43 4.86 10.7 18.7 25.6 37.0 57.8
Appendix 3 85

04196500 Sandusky River near Upper Sandusky, Ohio

Years analyzed = 64

Climatic year range = 1922–2008

[APEE, annual percentage equaled or exceeded; ft3/s, cubic foot per second]

Daily mean streamflow (ft3/s) that was equaled or exceeded the indicated percentage of time at APEE level

APEE 98 95 90 80 50 20 10 5 2

1 577. 1300. 1670. 1940. 3040. 3920. 5000. 5380. 6240.

2 463. 756. 1230. 1500. 2190. 2780. 3180. 4230. 5160.

5 247. 341. 537. 780. 1140. 1590. 1910. 2300. 2880.

10 158. 189. 267. 357. 652. 896. 1090. 1230. 1330.

20 56.1 77.8 122. 155. 285. 431. 536. 582. 648.

25 34.1 57.3 84.8 112. 219. 337. 413. 468. 484.

30 25.1 48.7 61.0 81.2 169. 271. 315. 365. 414.

40 13.5 21.7 31.5 49.6 114. 179. 209. 243. 268.

50 9.60 13.3 17.0 30.0 66.8 117. 143. 155. 195.

60 7.00 8.30 11.9 21.0 41.6 82.4 107. 121. 139.

70 4.85 6.44 8.82 14.0 24.5 49.2 69.4 87.1 103.

75 3.93 5.33 7.65 11.0 20.5 40.0 56.5 68.9 90.0

80 3.19 4.50 5.85 9.00 16.0 34.0 46.6 56.3 78.3

90 1.88 2.63 3.40 5.60 11.0 21.0 26.4 32.3 51.0

95 1.11 1.85 2.30 3.90 8.10 14.3 20.1 24.0 35.7

98 0.89 1.22 1.90 2.80 6.45 12.0 16.2 20.3 29.7

99 0.76 1.13 1.65 2.43 5.33 10.0 14.3 17.5 25.2

7-day mean streamflow (ft3/s) that was equaled or exceeded the indicated percentage of time at APEE level

APEE 98 95 90 80 50 20 10 5 2

1 383. 779. 1090. 1340. 2010. 2630. 2890. 3570. 3790.

2 322. 700. 850. 1130. 1520. 1990. 2290. 3020. 3230.

5 229. 357. 570. 866. 1140. 1420. 1690. 2250. 2710.

10 165. 175. 270. 464. 722. 934. 1070. 1310. 1720.

20 63.3 79.7 139. 175. 353. 564. 664. 744. 848.

25 31.0 60.0 92.7 138. 280. 461. 531. 644. 724.

30 24.0 48.0 63.2 88.4 207. 388. 451. 515. 609.

40 13.9 23.2 32.9 53.0 140. 222. 294. 348. 368.

50 9.95 14.4 18.1 33.4 84.7 147. 185. 220. 261.

60 7.56 8.86 12.3 22.6 47.9 101. 125. 145. 179.

70 5.12 7.01 9.86 13.4 27.1 61.4 87.6 103. 137.

75 4.46 5.49 8.26 11.2 23.1 42.9 64.9 86.5 117.

80 3.62 4.78 6.79 10.1 18.5 35.1 57.5 75.0 102.

90 2.03 2.77 3.68 6.39 12.5 24.1 33.1 40.9 66.3

95 1.42 2.14 2.36 4.60 8.95 17.7 22.4 27.9 41.8

98 0.91 1.53 1.95 3.23 7.36 13.4 18.7 22.0 36.7

99 0.86 1.34 1.77 2.76 6.60 12.3 16.4 20.9 35.5
86 Methods for Estimating Selected Low-Flow Statistics and Development of Annual Flow-Duration Statistics for Ohio

04197000 Sandusky River near Mexico, Ohio

Years analyzed = 55

Climatic year range = 1923–81

[APEE, annual percentage equaled or exceeded; ft3/s, cubic foot per second]

Daily mean streamflow (ft3/s) that was equaled or exceeded the indicated percentage of time at APEE level

APEE 98 95 90 80 50 20 10 5 2

1 1320. 2530. 3720. 4220. 6010. 8120. 9060. 10700. 10900.

2 1000. 1690. 2590. 3280. 4980. 6430. 7110. 8570. 9180.

5 545. 730. 1160. 1760. 2930. 4100. 4400. 4900. 5930.

10 373. 431. 589. 801. 1380. 2300. 2740. 3170. 4190.

20 166. 185. 249. 331. 623. 1140. 1470. 1660. 1930.

25 82.9 141. 186. 244. 499. 800. 1070. 1220. 1520.

30 59.7 110. 137. 175. 359. 598. 779. 916. 1170.

40 37.4 53.6 75.4 105. 239. 387. 466. 596. 726.

50 27.0 34.9 48.0 68.2 141. 264. 332. 409. 507.

60 21.0 26.6 34.0 49.2 94.6 173. 223. 281. 317.

70 16.6 21.0 25.6 34.4 57.4 106. 146. 195. 220.

75 14.4 18.6 22.6 30.8 45.8 91.3 124. 154. 184.

80 12.4 15.8 19.6 26.0 39.0 75.0 97.5 136. 141.

90 9.00 11.4 13.2 18.0 26.6 51.9 60.5 79.9 106.

95 7.94 9.80 10.2 13.0 20.0 40.7 51.4 56.1 87.8

98 4.82 7.44 8.50 9.93 17.0 37.4 43.0 47.0 73.6

99 3.44 5.54 6.66 8.92 15.3 34.0 39.9 43.1 67.7

7-day mean streamflow (ft3/s) that was equaled or exceeded the indicated percentage of time at APEE level

APEE 98 95 90 80 50 20 10 5 2

1 839. 1850. 2440. 3140. 4700. 6380. 7230. 8540. 9800.

2 734. 1400. 2070. 2430. 3570. 5030. 5510. 7140. 7270.

5 468. 654. 1250. 1810. 2680. 3650. 4070. 4670. 5440.

10 347. 411. 601. 943. 1630. 2320. 2690. 3010. 3490.

20 176. 188. 268. 391. 755. 1350. 1520. 1890. 2200.

25 73.6 136. 199. 270. 551. 1060. 1300. 1520. 1820.

30 56.7 105. 149. 195. 441. 818. 1060. 1260. 1480.

40 37.1 52.3 75.8 116. 245. 454. 650. 844. 919.

50 29.6 36.4 48.6 72.2 156. 320. 428. 543. 605.

60 22.8 27.3 35.1 47.6 106. 204. 270. 360. 397.

70 17.7 22.1 27.1 35.2 63.7 134. 175. 229. 286.

75 15.5 17.6 24.5 31.5 46.4 99.8 146. 200. 223.

80 13.4 16.3 21.5 27.5 39.6 86.9 111. 176. 185.

90 9.50 11.5 14.4 18.0 29.4 59.2 65.9 85.9 126.

95 7.99 9.60 11.6 13.8 20.7 45.0 55.7 58.7 103.

98 5.76 7.88 9.30 12.3 17.6 39.7 49.2 50.8 98.3

99 5.09 7.01 8.00 10.0 16.9 37.1 44.9 47.7 93.7
Appendix 3 87

04197100 Honey Creek at Melmore, Ohio

Years analyzed = 33

Climatic year range = 1976–2008

[APEE, annual percentage equaled or exceeded; ft3/s, cubic foot per second]

Daily mean streamflow (ft3/s) that was equaled or exceeded the indicated percentage of time at APEE level

APEE 95 90 80 70 50 30 20 10 5

1 604. 828. 919. 1230. 1610. 1880. 2160. 2700. 2800.

2 381. 719. 795. 930. 1160. 1290. 1600. 1990. 2220.

5 194. 326. 477. 501. 678. 847. 912. 1110. 1250.

10 104. 140. 216. 285. 340. 469. 566. 718. 792.

20 43.5 50.6 80.0 102. 130. 213. 249. 290. 327.

25 31.9 38.2 57.4 72.6 101. 155. 173. 213. 228.

30 26.0 31.4 44.5 57.5 75.2 109. 126. 151. 167.

40 12.7 17.2 26.6 34.3 49.2 64.6 76.8 96.9 116.

50 5.91 9.50 16.2 20.2 30.0 42.0 51.5 60.8 82.7

60 3.68 5.04 9.42 13.0 20.4 31.4 37.4 41.2 65.0

70 1.71 2.60 3.76 7.02 10.0 20.2 24.0 30.6 47.8

75 1.13 1.66 2.92 4.73 8.98 13.6 20.0 26.6 39.2

80 0.86 1.26 2.02 2.92 6.32 9.82 16.2 22.6 31.5

90 0.44 0.78 1.34 1.50 3.20 5.38 7.73 14.6 17.0

95 0.29 0.58 1.00 1.11 2.23 3.48 4.11 10.1 12.1

98 0.17 0.45 0.67 0.95 1.63 2.76 3.25 6.54 9.34

99 0.14 0.37 0.55 0.87 1.17 2.55 2.95 4.17 7.30

7-day mean streamflow (ft3/s) that was equaled or exceeded the indicated percentage of time at APEE level

APEE 95 90 80 70 50 30 20 10 5

1 422. 524. 678. 786. 1020. 1290. 1450. 1680. 1830.

2 312. 416. 525. 634. 817. 943. 1310. 1500. 1680.

5 178. 344. 389. 467. 633. 707. 918. 1080. 1160.

10 120. 155. 268. 317. 382. 496. 524. 666. 803.

20 48.1 64.3 99.6 123. 188. 276. 312. 390. 419.

25 36.6 46.1 74.7 95.8 145. 193. 245. 310. 335.

30 26.3 35.6 58.0 67.4 110. 157. 189. 234. 291.

40 14.7 17.7 34.8 41.1 65.6 98.2 118. 150. 171.

50 6.79 10.3 18.5 23.2 36.6 54.5 74.6 96.1 112.

60 4.16 6.05 10.0 14.7 22.7 38.4 50.7 56.2 85.5

70 1.98 2.85 4.07 7.47 13.6 23.7 30.2 37.5 65.0

75 1.21 1.91 3.35 5.31 11.0 17.3 23.9 31.9 55.9

80 0.90 1.36 2.39 3.20 7.01 12.1 19.2 27.3 44.8

90 0.47 0.81 1.52 1.82 3.53 6.14 10.8 17.8 25.5

95 0.30 0.62 1.06 1.25 2.36 3.91 4.76 13.5 14.3

98 0.19 0.51 0.79 0.98 1.90 2.98 3.83 9.12 11.6

99 0.16 0.47 0.64 0.93 1.63 2.70 3.23 6.07 10.4
88 Methods for Estimating Selected Low-Flow Statistics and Development of Annual Flow-Duration Statistics for Ohio

04197170 Rock Creek at Tiffin, Ohio

Years analyzed = 25

Climatic year range = 1984–2008

[APEE, annual percentage equaled or exceeded; ft3/s, cubic foot per second]

Daily mean streamflow (ft3/s) that was equaled or exceeded the indicated percentage of time at APEE level

APEE 95 90 80 70 50 30 20 10 5

1 147. 221. 347. 449. 491. 590. 731. 942. 1050.

2 107. 133. 204. 268. 345. 383. 504. 608. 704.

5 37.0 57.8 88.0 104. 139. 183. 234. 259. 303.

10 16.6 19.8 34.5 36.2 60.0 84.5 86.0 119. 149.

20 7.40 8.61 13.4 15.9 23.0 27.0 32.1 42.5 56.0

25 6.27 6.88 10.2 12.8 15.5 19.6 20.8 29.6 38.6

30 4.91 5.68 9.20 9.94 13.0 16.0 16.2 22.1 30.7

40 3.13 3.54 6.18 7.00 8.32 11.0 11.0 14.0 17.8

50 2.20 2.44 3.22 4.95 6.60 7.76 8.81 11.0 13.0

60 1.73 1.86 2.32 3.33 4.38 5.41 6.12 8.72 9.85

70 1.29 1.55 1.88 2.36 3.20 4.04 4.34 7.18 7.72

75 1.19 1.40 1.70 1.99 2.80 3.28 3.76 6.57 6.81

80 1.03 1.20 1.44 1.70 2.40 2.90 3.28 5.79 5.98

90 0.77 0.88 1.10 1.28 1.80 2.12 2.54 4.02 4.44

95 0.56 0.68 0.93 1.15 1.40 1.90 2.15 3.03 3.63

98 0.39 0.47 0.78 1.00 1.13 1.53 1.93 2.44 3.27

99 0.35 0.43 0.72 0.92 1.10 1.37 1.66 2.12 2.95

7-day mean streamflow (ft3/s) that was equaled or exceeded the indicated percentage of time at APEE level

APEE 95 90 80 70 50 30 20 10 5

1 106. 138. 166. 192. 289. 333. 364. 428. 474.

2 65.3 90.1 125. 167. 207. 256. 323. 378. 419.

5 47.3 67.5 110. 128. 154. 189. 198. 262. 276.

10 26.6 34.9 48.1 75.9 90.3 109. 126. 186. 206.

20 8.89 11.7 17.7 26.1 35.6 51.5 70.0 76.0 98.9

25 7.13 8.30 15.1 21.0 28.4 38.3 46.5 60.2 79.4

30 5.95 6.61 12.5 14.0 21.1 28.4 33.3 52.1 65.9

40 3.20 3.56 7.47 8.89 12.8 16.8 17.7 29.1 34.7

50 2.32 2.53 4.12 5.66 9.13 10.8 11.3 16.3 22.0

60 1.83 1.93 2.56 3.72 4.91 7.06 8.47 12.8 17.6

70 1.38 1.62 2.03 2.50 3.43 4.56 5.33 9.63 12.4

75 1.24 1.52 1.74 2.16 2.93 3.87 4.44 7.84 9.87

80 1.05 1.28 1.53 1.82 2.54 3.12 3.63 6.86 7.96

90 0.84 0.92 1.17 1.37 1.83 2.25 2.70 4.76 5.17

95 0.60 0.74 0.96 1.19 1.53 1.95 2.19 3.55 4.14

98 0.47 0.64 0.84 1.12 1.21 1.79 2.10 2.63 3.34

99 0.43 0.57 0.81 1.04 1.16 1.62 1.83 2.35 3.20
Appendix 3 89

04198000 Sandusky River near Fremont, Ohio

Years analyzed = 81

Climatic year range = 1924–2008

[APEE, annual percentage equaled or exceeded; ft3/s, cubic foot per second]

Daily mean streamflow (ft3/s) that was equaled or exceeded the indicated percentage of time at APEE level

APEE 98 95 90 80 50 20 10 5 2

1 2670. 4490. 6220. 7320. 10900. 14600. 16800. 20000. 22300.

2 1780. 3270. 4350. 5730. 8240. 10800. 13600. 15300. 16400.

5 912. 1670. 2280. 3290. 5060. 6840. 7920. 9900. 11000.

10 650. 883. 1170. 1510. 2500. 4080. 5040. 6030. 7090.

20 283. 321. 476. 634. 1150. 1970. 2600. 2970. 3430.

25 163. 253. 343. 447. 890. 1460. 1980. 2250. 2420.

30 121. 209. 258. 358. 680. 1100. 1460. 1630. 1860.

40 69.3 101. 150. 201. 437. 684. 874. 1010. 1210.

50 48.6 65.7 81.6 120. 286. 477. 564. 706. 825.

60 36.6 45.9 59.4 85.8 199. 347. 396. 506. 637.

70 28.1 37.0 43.4 59.5 121. 229. 298. 368. 486.

75 24.6 33.5 40.2 47.8 86.0 181. 256. 307. 439.

80 21.6 28.6 33.0 40.0 71.2 140. 212. 265. 404.

90 12.6 21.2 24.0 28.0 46.0 78.7 118. 198. 269.

95 9.94 13.1 17.1 22.9 39.3 66.2 88.8 132. 193.

98 7.32 10.2 13.7 19.4 33.3 55.6 63.9 93.5 157.

99 6.20 10.1 12.4 17.1 30.0 49.5 59.1 89.2 140.

7-day mean streamflow (ft3/s) that was equaled or exceeded the indicated percentage of time at APEE level

APEE 98 95 90 80 50 20 10 5 2

1 1710. 2970. 4240. 5230. 7710. 10900. 12700. 14400. 17800.

2 1580. 2290. 3280. 4230. 6110. 8280. 10200. 12000. 13400.

5 782. 1790. 2320. 3050. 4630. 6150. 7210. 8760. 9180.

10 560. 841. 1140. 1730. 2820. 4150. 4800. 5570. 6500.

20 280. 331. 561. 755. 1390. 2350. 3000. 3570. 3940.

25 146. 252. 376. 548. 1080. 1830. 2520. 2890. 3200.

30 118. 221. 296. 413. 816. 1460. 1910. 2340. 2610.

40 67.7 122. 158. 220. 518. 845. 1240. 1460. 1530.

50 49.6 61.9 83.8 132. 314. 588. 755. 891. 1080.

60 38.6 48.0 58.6 92.5 217. 403. 481. 640. 821.

70 31.1 39.5 43.6 60.7 132. 261. 349. 462. 624.

75 25.7 35.4 40.0 50.4 97.9 210. 304. 401. 545.

80 22.5 31.0 34.2 42.6 77.3 170. 245. 321. 476.

90 12.9 21.9 24.6 28.9 49.7 87.3 134. 221. 354.

95 11.0 15.8 18.1 24.4 40.6 69.4 97.1 138. 239.

98 7.62 11.3 14.6 22.1 36.3 59.4 72.7 109. 179.

99 7.00 10.9 13.3 20.8 33.9 53.7 69.4 97.9 162.
90 Methods for Estimating Selected Low-Flow Statistics and Development of Annual Flow-Duration Statistics for Ohio

04199000 Huron River at Milan, Ohio

Years analyzed = 52

Climatic year range = 1950–2008

[APEE, annual percentage equaled or exceeded; ft3/s, cubic foot per second]

Daily mean streamflow (ft3/s) that was equaled or exceeded the indicated percentage of time at APEE level

APEE 98 95 90 80 50 20 10 5 2

1 1340. 1460. 1990. 2890. 4100. 5610. 6620. 7620. 8540.

2 831. 1170. 1400. 1740. 2780. 3960. 4430. 5330. 6110.

5 503. 513. 618. 808. 1390. 1990. 2280. 2920. 3490.

10 212. 234. 307. 430. 677. 1070. 1310. 1580. 1630.

20 69.5 128. 151. 201. 334. 527. 624. 797. 845.

25 49.3 98.2 122. 144. 258. 424. 507. 627. 656.

30 34.6 82.5 92.6 116. 201. 341. 403. 486. 503.

40 20.8 49.6 55.7 71.4 129. 242. 271. 326. 364.

50 14.8 29.0 35.5 45.6 90.0 163. 190. 237. 257.

60 12.5 20.6 22.6 33.0 58.5 113. 151. 172. 180.

70 10.2 15.8 19.0 24.9 39.5 72.7 86.0 125. 141.

75 9.25 13.3 16.8 21.3 33.5 55.8 66.0 106. 126.

80 7.99 11.7 15.0 17.1 28.0 47.5 58.2 93.0 110.

90 5.64 7.90 9.60 11.6 18.5 34.2 39.9 65.1 65.6

95 5.02 5.56 6.55 9.02 15.0 25.2 33.8 43.7 50.1

98 3.65 4.50 5.11 7.16 12.5 21.4 28.7 31.9 40.8

99 3.18 4.04 4.49 6.30 11.0 20.0 24.7 29.2 37.2

7-day mean streamflow (ft3/s) that was equaled or exceeded the indicated percentage of time at APEE level

APEE 98 95 90 80 50 20 10 5 2

1 952. 1190. 1400. 1710. 2340. 3190. 3980. 4260. 6450.

2 782. 890. 1060. 1400. 1930. 2700. 3390. 3530. 3810.

5 478. 509. 687. 1010. 1340. 1880. 2250. 2460. 2630.

10 301. 331. 354. 495. 888. 1300. 1510. 1750. 2020.

20 66.1 139. 174. 242. 433. 700. 864. 1010. 1260.

25 46.9 100. 136. 187. 335. 541. 711. 856. 962.

30 36.2 88.5 106. 138. 259. 462. 567. 660. 728.

40 21.1 59.0 66.8 83.6 167. 332. 402. 464. 544.

50 14.8 30.0 38.0 52.0 112. 207. 273. 337. 368.

60 13.1 21.6 26.4 38.6 68.3 150. 185. 233. 258.

70 10.5 15.8 20.5 25.7 47.0 93.4 134. 164. 202.

75 9.36 14.0 18.6 22.1 37.7 68.4 87.2 142. 180.

80 8.20 12.8 15.7 18.1 31.0 53.5 70.4 124. 149.

90 5.84 8.65 10.3 12.0 21.0 38.7 46.3 77.3 95.7

95 5.39 5.79 7.28 9.60 16.2 30.3 38.0 52.4 61.1

98 4.02 4.66 5.75 8.58 12.9 25.5 34.3 40.2 48.3

99 3.88 4.49 5.11 7.57 12.4 23.3 30.0 34.9 47.2
Appendix 3 91

04199500 Vermilion River near Vermilion, Ohio

Years analyzed = 39

Climatic year range = 1950–2008

[APEE, annual percentage equaled or exceeded; ft3/s, cubic foot per second]

Daily mean streamflow (ft3/s) that was equaled or exceeded the indicated percentage of time at APEE level

APEE 95 90 80 70 50 30 20 10 5

1 1500. 2240. 2410. 2620. 3280. 3610. 4470. 5580. 7650.

2 763. 1250. 1580. 1890. 2230. 2490. 2830. 4350. 5740.

5 320. 520. 722. 893. 1240. 1310. 1710. 2250. 2710.

10 168. 254. 312. 495. 582. 860. 1020. 1150. 1220.

20 83.6 117. 145. 208. 269. 360. 411. 532. 625.

25 57.5 94.0 104. 151. 200. 264. 309. 421. 455.

30 45.2 65.2 74.0 112. 153. 213. 234. 341. 361.

40 22.6 29.2 47.6 60.2 98.8 130. 152. 202. 254.

50 12.0 17.0 29.0 39.0 62.5 95.0 111. 137. 170.

60 8.00 8.04 14.4 23.0 39.0 63.0 76.4 101. 120.

70 3.30 4.88 8.21 15.0 22.0 41.0 46.8 60.6 72.8

75 2.55 3.85 5.55 10.0 15.5 28.5 33.0 42.5 62.8

80 1.20 3.06 4.30 7.42 11.2 20.0 26.0 35.0 56.0

90 0.07 1.00 2.26 3.00 5.10 11.0 13.6 20.7 28.0

95 0.00 0.30 1.24 1.94 3.40 7.72 9.20 14.0 16.4

98 0.00 0.10 0.70 1.20 2.30 5.50 6.93 9.63 11.0

99 0.00 0.10 0.50 0.95 2.03 4.73 6.16 8.87 9.87

7-day mean streamflow (ft3/s) that was equaled or exceeded the indicated percentage of time at APEE level

APEE 95 90 80 70 50 30 20 10 5

1 1190. 1220. 1550. 1640. 1990. 2380. 3090. 3490. 7260.

2 830. 898. 1140. 1330. 1520. 1950. 2260. 3030. 3410.

5 319. 580. 813. 947. 1150. 1210. 1300. 2030. 2510.

10 227. 265. 374. 516. 640. 849. 1040. 1510. 1570.

20 85.3 126. 175. 236. 358. 543. 614. 719. 752.

25 68.3 96.6 132. 180. 254. 411. 481. 567. 613.

30 47.6 65.6 89.6 146. 198. 294. 388. 447. 478.

40 25.6 29.9 50.4 72.6 125. 187. 216. 290. 334.

50 13.9 19.6 31.4 45.4 76.6 114. 145. 195. 208.

60 8.43 9.97 16.4 28.9 48.0 86.6 98.7 132. 139.

70 3.61 4.89 10.2 15.3 25.7 52.9 61.4 78.4 103.

75 2.43 3.97 6.89 10.6 18.4 36.1 42.9 55.3 78.7

80 1.51 3.29 4.94 8.67 13.4 22.7 30.8 42.0 63.7

90 0.19 1.44 2.63 3.64 6.65 14.1 16.4 25.5 45.5

95 0.00 0.39 1.68 2.14 3.84 8.71 11.3 17.4 21.4

98 0.00 0.19 0.99 1.47 2.60 6.67 8.19 12.7 15.3

99 0.00 0.11 0.96 1.11 2.41 5.81 6.97 11.3 13.4
92 Methods for Estimating Selected Low-Flow Statistics and Development of Annual Flow-Duration Statistics for Ohio

04207200 Tinkers Creek at Bedford, Ohio

Years analyzed = 46

Climatic year range = 1963–2008

[APEE, annual percentage equaled or exceeded; ft3/s, cubic foot per second]

Daily mean streamflow (ft3/s) that was equaled or exceeded the indicated percentage of time at APEE level

APEE 95 90 80 70 50 30 20 10 5

1 641. 735. 815. 941. 1140. 1230. 1280. 1430. 1540.

2 557. 573. 634. 718. 800. 918. 957. 1030. 1130.

5 289. 349. 400. 435. 490. 595. 644. 739. 826.

10 189. 208. 253. 279. 307. 381. 436. 475. 519.

20 105. 118. 129. 143. 175. 209. 236. 264. 283.

25 88.0 93.3 99.7 120. 135. 166. 180. 206. 215.

30 70.3 75.9 85.0 96.3 115. 140. 149. 178. 181.

40 42.4 54.6 61.4 68.9 86.8 100. 112. 134. 140.

50 25.4 41.6 48.1 55.1 70.0 77.8 85.0 105. 113.

60 17.7 28.8 38.9 43.0 53.0 61.8 68.4 81.0 90.1

70 14.1 21.5 32.0 35.0 41.0 49.9 53.0 60.6 66.0

75 11.7 18.5 28.8 30.1 35.4 43.0 46.3 52.2 58.2

80 10.3 15.1 24.4 29.0 31.6 37.0 39.7 46.7 49.7

90 8.86 11.0 19.0 21.6 25.0 27.9 30.6 35.0 36.5

95 7.80 10.4 17.0 19.0 22.0 24.9 26.7 29.2 31.0

98 7.20 9.12 14.4 16.1 20.0 22.0 23.0 26.3 27.6

99 6.96 8.76 13.4 15.2 18.8 21.6 22.6 25.3 26.6

7-day mean streamflow (ft3/s) that was equaled or exceeded the indicated percentage of time at APEE level

APEE 95 90 80 70 50 30 20 10 5

1 411. 473. 550. 606. 703. 814. 852. 981. 1070.

2 372. 429. 464. 497. 583. 637. 704. 778. 835.

5 252. 300. 318. 359. 421. 487. 520. 569. 619.

10 174. 210. 241. 264. 306. 355. 403. 424. 464.

20 115. 124. 157. 164. 200. 235. 278. 306. 321.

25 97.9 108. 119. 135. 158. 200. 222. 264. 293.

30 77.8 84.4 99.5 116. 137. 169. 190. 219. 244.

40 46.4 57.6 71.5 86.5 101. 127. 144. 171. 194.

50 28.4 47.2 56.1 65.4 82.0 95.8 105. 135. 143.

60 18.7 35.7 46.4 51.9 63.0 73.5 80.6 106. 114.

70 15.6 26.2 37.2 42.3 49.6 61.6 65.5 81.3 83.2

75 13.9 22.0 33.3 37.7 43.5 54.2 57.5 67.6 71.0

80 12.4 18.8 29.1 33.0 38.6 46.4 52.1 57.6 63.2

90 10.5 14.0 22.9 25.7 29.6 35.7 39.3 44.6 45.9

95 9.25 11.7 18.5 21.9 25.8 30.0 31.1 35.4 36.6

98 7.65 10.7 16.0 18.4 23.5 26.1 28.5 31.3 32.4

99 7.24 9.71 14.9 17.6 21.9 24.0 25.7 28.7 29.8
Appendix 3 93

04211000 Rock Creek near Rock Creek, Ohio

Years analyzed = 24

Climatic year range = 1942–65

[APEE, annual percentage equaled or exceeded; ft3/s, cubic foot per second]

Daily mean streamflow (ft3/s) that was equaled or exceeded the indicated percentage of time at APEE level

APEE 95 90 80 70 50 30 20 10 5

1 500. 542. 698. 784. 931. 1160. 1260. 1410. 1490.

2 249. 353. 505. 570. 695. 810. 921. 973. 981.

5 161. 181. 287. 336. 408. 452. 560. 608. 652.

10 74.5 103. 147. 157. 205. 243. 300. 344. 365.

20 26.4 34.1 53.6 61.3 86.9 105. 119. 133. 158.

25 18.3 22.8 36.0 41.6 60.8 73.8 81.0 99.4 116.

30 14.0 14.6 24.2 29.4 42.6 56.0 63.4 76.5 89.0

40 5.28 9.37 12.0 12.5 23.5 35.0 38.2 45.0 50.4

50 2.63 3.20 5.35 6.50 10.3 18.5 21.0 28.0 31.0

60 0.63 1.10 1.30 2.44 4.28 9.98 16.0 18.5 19.0

70 0.00 0.05 0.30 0.95 1.94 2.77 5.80 10.1 11.6

75 0.00 0.00 0.20 0.28 0.93 1.40 4.00 7.18 8.39

80 0.00 0.00 0.00 0.00 0.60 0.85 2.60 4.80 5.57

90 0.00 0.00 0.00 0.00 0.15 0.30 1.00 2.65 3.99

95 0.00 0.00 0.00 0.00 0.00 0.15 0.30 1.71 2.98

98 0.00 0.00 0.00 0.00 0.00 0.02 0.10 1.05 2.34

99 0.00 0.00 0.00 0.00 0.00 0.00 0.07 0.68 2.22

7-day mean streamflow (ft3/s) that was equaled or exceeded the indicated percentage of time at APEE level

APEE 95 90 80 70 50 30 20 10 5

1 282. 365. 397. 497. 556. 699. 746. 822. 932.

2 252. 292. 318. 354. 461. 556. 655. 712. 752.

5 146. 185. 236. 254. 337. 399. 425. 501. 565.

10 88.9 108. 189. 204. 237. 268. 305. 351. 386.

20 33.0 44.1 77.4 106. 128. 154. 173. 208. 239.

25 21.9 26.1 51.9 67.5 89.7 123. 126. 164. 208.

30 16.4 17.4 30.5 47.6 61.4 90.7 103. 133. 172.

40 5.68 9.93 15.6 20.2 37.6 54.8 62.0 79.1 103.

50 2.79 3.70 5.34 7.74 19.1 27.2 33.6 41.0 58.6

60 0.62 1.27 1.33 3.06 4.88 12.6 18.7 27.1 32.0

70 0.01 0.15 0.50 1.35 2.01 4.41 9.09 15.5 18.1

75 0.00 0.00 0.20 0.36 1.21 2.11 5.39 9.90 12.1

80 0.00 0.00 0.00 0.09 0.63 1.02 4.21 7.35 8.10

90 0.00 0.00 0.00 0.00 0.24 0.45 1.21 3.75 4.91

95 0.00 0.00 0.00 0.00 0.03 0.21 0.39 2.15 3.89

98 0.00 0.00 0.00 0.00 0.00 0.08 0.19 1.54 2.79

99 0.00 0.00 0.00 0.00 0.00 0.02 0.13 1.06 2.53
94 Methods for Estimating Selected Low-Flow Statistics and Development of Annual Flow-Duration Statistics for Ohio

04212000 Grand River near Madison, Ohio

Years analyzed = 48

Climatic year range = 1923–73

[APEE, annual percentage equaled or exceeded; ft3/s, cubic foot per second]

Daily mean streamflow (ft3/s) that was equaled or exceeded the indicated percentage of time at APEE level

APEE 95 90 80 70 50 30 20 10 5

1 3720. 4300. 4970. 5370. 6250. 6690. 7330. 7740. 8590.

2 2680. 3160. 3660. 4180. 4830. 5190. 5550. 6360. 6780.

5 1450. 1690. 2370. 2630. 3090. 3510. 3630. 4560. 4690.

10 908. 1080. 1320. 1620. 2010. 2300. 2590. 2790. 2890.

20 395. 417. 639. 749. 1010. 1220. 1420. 1600. 1710.

25 242. 317. 398. 516. 673. 932. 1020. 1290. 1330.

30 158. 208. 271. 368. 513. 689. 796. 955. 1010.

40 82.1 109. 144. 200. 295. 388. 459. 580. 625.

50 48.7 59.9 79.8 93.2 173. 252. 294. 393. 432.

60 26.4 27.9 40.0 48.0 73.2 159. 184. 255. 277.

70 13.9 15.0 18.9 24.6 35.9 76.7 103. 134. 187.

75 9.89 12.0 15.8 17.9 25.4 49.3 70.4 108. 146.

80 8.16 9.98 12.0 12.1 19.5 32.0 47.8 80.1 94.8

90 3.26 4.64 6.36 7.52 10.5 16.5 22.8 31.0 43.0

95 1.20 2.10 4.32 4.74 8.30 12.0 14.6 23.1 26.6

98 0.42 1.20 2.14 3.14 6.90 9.40 11.1 17.2 24.2

99 0.17 0.77 1.59 2.60 5.33 9.05 10.0 15.1 22.6

7-day mean streamflow (ft3/s) that was equaled or exceeded the indicated percentage of time at APEE level

APEE 95 90 80 70 50 30 20 10 5

1 2390. 2700. 3180. 3670. 4270. 4770. 5510. 6160. 6360.

2 1990. 2280. 2710. 3040. 3580. 4110. 4320. 5010. 5160.

5 1410. 1710. 2060. 2420. 2670. 3060. 3210. 3820. 3970.

10 948. 1080. 1390. 1740. 2000. 2210. 2390. 2600. 2890.

20 460. 546. 720. 949. 1170. 1330. 1550. 1770. 1950.

25 282. 357. 522. 661. 897. 1100. 1200. 1520. 1620.

30 181. 241. 368. 493. 648. 896. 1010. 1220. 1340.

40 89.8 109. 192. 236. 352. 514. 623. 750. 914.

50 50.7 61.5 86.0 99.8 193. 310. 347. 521. 601.

60 24.9 27.8 43.5 50.6 87.3 190. 212. 350. 376.

70 13.5 15.3 21.6 25.9 38.0 100. 130. 161. 239.

75 10.4 12.1 16.8 19.0 30.0 58.5 74.7 125. 177.

80 8.51 9.62 12.6 13.6 22.0 38.0 59.1 95.5 131.

90 4.17 5.26 6.97 7.78 11.8 18.7 26.2 34.7 47.8

95 1.88 2.98 4.89 5.67 8.88 12.8 16.1 25.2 29.1

98 0.99 1.39 2.67 4.14 7.23 10.5 12.2 21.4 24.8

99 0.36 1.04 2.01 3.44 6.31 9.99 11.3 17.9 23.9
Appendix 3 95

04212100 Grand River near Painesville, Ohio

Years analyzed = 34

Climatic year range = 1975–2008

[APEE, annual percentage equaled or exceeded; ft3/s, cubic foot per second]

Daily mean streamflow (ft3/s) that was equaled or exceeded the indicated percentage of time at APEE level

APEE 95 90 80 70 50 30 20 10 5

1 5160. 5600. 6480. 7030. 7950. 9580. 10000. 10300. 10600.

2 3890. 4350. 5270. 5470. 6140. 6900. 7640. 8160. 8880.

5 2350. 2620. 3080. 3580. 3960. 4760. 5190. 5730. 6220.

10 1470. 1730. 1990. 2240. 2690. 3340. 3530. 3940. 4170.

20 822. 914. 1020. 1220. 1410. 1900. 2160. 2350. 2730.

25 603. 699. 786. 970. 1090. 1550. 1750. 1890. 2210.

30 379. 488. 669. 732. 863. 1100. 1390. 1610. 1870.

40 202. 289. 373. 471. 596. 699. 921. 1170. 1320.

50 119. 181. 223. 332. 410. 503. 640. 841. 975.

60 60.4 104. 151. 204. 264. 323. 412. 583. 629.

70 42.3 62.4 89.8 109. 156. 218. 243. 356. 438.

75 30.1 38.3 70.0 78.0 109. 174. 202. 284. 327.

80 22.8 29.6 43.0 56.7 87.7 130. 165. 205. 234.

90 11.7 14.5 25.0 29.0 50.5 73.3 82.4 95.8 115.

95 8.71 10.4 17.0 20.3 35.1 44.3 51.6 67.7 76.5

98 6.33 7.70 13.0 15.3 26.2 35.7 38.3 51.6 58.2

99 5.04 7.23 11.7 13.7 22.8 30.6 32.7 47.5 53.9

7-day mean streamflow (ft3/s) that was equaled or exceeded the indicated percentage of time at APEE level

APEE 95 90 80 70 50 30 20 10 5

1 3000. 3550. 4230. 4860. 6620. 7310. 7540. 7920. 8740.

2 2810. 3020. 3960. 4460. 4910. 5710. 6130. 6590. 7120.

5 2180. 2410. 2830. 3130. 3340. 3770. 4380. 4770. 5400.

10 1350. 1840. 2040. 2250. 2580. 3070. 3340. 3570. 3950.

20 862. 960. 1170. 1410. 1630. 2040. 2140. 2600. 3040.

25 698. 761. 879. 1100. 1280. 1670. 1820. 2260. 2600.

30 396. 598. 762. 859. 1070. 1290. 1650. 1810. 2240.

40 201. 365. 435. 562. 752. 880. 1150. 1370. 1700.

50 116. 195. 266. 400. 482. 586. 842. 1050. 1190.

60 57.3 113. 176. 235. 321. 406. 470. 779. 877.

70 44.1 70.0 101. 111. 193. 267. 297. 517. 639.

75 36.5 44.2 82.0 90.2 135. 218. 257. 422. 504.

80 24.5 31.8 49.0 67.5 99.6 168. 223. 287. 401.

90 13.7 17.1 26.6 32.3 57.2 84.0 114. 136. 154.

95 10.3 12.0 17.6 22.7 40.9 54.5 65.6 76.2 90.1

98 7.76 9.46 14.6 18.7 31.1 45.1 54.6 58.1 71.9

99 6.35 7.71 13.1 15.2 27.6 36.9 41.3 52.8 68.3
96 Methods for Estimating Selected Low-Flow Statistics and Development of Annual Flow-Duration Statistics for Ohio

04212500 Ashtabula River near Ashtabula, Ohio

Years analyzed = 47

Climatic year range = 1925–78

[APEE, annual percentage equaled or exceeded; ft3/s, cubic foot per second]

Daily mean streamflow (ft3/s) that was equaled or exceeded the indicated percentage of time at APEE level

APEE 95 90 80 70 50 30 20 10 5

1 960. 1110. 1340. 1470. 1690. 1930. 2130. 2600. 2670.

2 710. 756. 940. 1110. 1250. 1440. 1540. 1690. 1820.

5 416. 447. 532. 617. 743. 857. 936. 1010. 1080.

10 207. 237. 270. 350. 395. 481. 501. 551. 643.

20 82.0 103. 132. 147. 196. 234. 258. 288. 335.

25 60.8 64.5 90.5 106. 135. 171. 192. 217. 237.

30 46.1 49.6 67.1 78.2 110. 132. 144. 170. 191.

40 22.0 30.8 36.8 45.2 70.0 84.2 97.0 119. 125.

50 12.0 13.0 18.2 28.0 43.0 55.0 65.0 76.4 87.6

60 4.28 4.78 6.75 8.24 21.0 32.4 42.4 48.2 56.0

70 0.95 1.48 2.00 3.12 9.00 16.5 20.4 31.2 37.3

75 0.18 0.62 1.16 1.50 4.00 10.0 13.0 24.0 26.8

80 0.04 0.28 0.47 0.80 2.04 6.66 8.08 17.0 19.8

90 0.00 0.00 0.00 0.12 0.50 1.62 2.72 6.52 8.14

95 0.00 0.00 0.00 0.00 0.20 0.86 1.56 3.50 4.73

98 0.00 0.00 0.00 0.00 0.00 0.49 1.04 2.55 3.44

99 0.00 0.00 0.00 0.00 0.00 0.41 0.76 1.89 2.80

7-day mean streamflow (ft3/s) that was equaled or exceeded the indicated percentage of time at APEE level

APEE 95 90 80 70 50 30 20 10 5

1 536. 668. 736. 834. 1080. 1230. 1350. 1500. 1550.

2 469. 566. 657. 685. 813. 930. 994. 1130. 1210.

5 335. 408. 482. 541. 609. 682. 729. 870. 892.

10 243. 285. 322. 398. 432. 488. 528. 618. 632.

20 120. 129. 177. 219. 259. 317. 354. 399. 443.

25 82.9 98.7 140. 164. 212. 257. 281. 314. 351.

30 50.3 59.3 105. 123. 160. 198. 238. 268. 287.

40 25.7 34.6 51.3 63.0 92.9 111. 147. 195. 205.

50 14.4 15.4 23.4 33.9 53.4 67.5 84.4 115. 124.

60 4.48 5.12 7.42 9.19 26.8 41.9 51.9 76.6 80.9

70 0.96 1.54 2.43 3.25 10.2 20.3 31.4 42.9 54.3

75 0.31 0.77 1.37 2.02 4.73 14.1 21.0 32.9 43.3

80 0.10 0.32 0.64 0.98 2.66 9.62 13.0 24.1 29.8

90 0.00 0.00 0.06 0.20 0.61 1.88 3.31 8.71 10.0

95 0.00 0.00 0.00 0.03 0.35 0.89 1.91 4.20 6.28

98 0.00 0.00 0.00 0.00 0.06 0.67 1.27 3.58 4.12

99 0.00 0.00 0.00 0.00 0.01 0.57 1.11 2.44 3.61
Appendix 3 97

04213000 Conneaut Creek at Conneaut, Ohio

Years analyzed = 71

Climatic year range = 1923–2008

[APEE, annual percentage equaled or exceeded; ft3/s, cubic foot per second]

Daily mean streamflow (ft3/s) that was equaled or exceeded the indicated percentage of time at APEE level

APEE 98 95 90 80 50 20 10 5 2

1 1030. 1530. 1680. 2050. 2670. 3350. 3680. 3940. 5390.

2 859. 1180. 1310. 1440. 1950. 2530. 2640. 2790. 3510.

5 580. 691. 737. 902. 1200. 1470. 1680. 1820. 2030.

10 358. 381. 427. 526. 713. 892. 984. 1180. 1400.

20 182. 190. 204. 247. 344. 471. 554. 608. 691.

25 133. 154. 163. 198. 273. 370. 444. 488. 535.

30 97.5 120. 126. 151. 220. 302. 351. 406. 452.

40 56.9 68.3 78.3 100. 150. 205. 229. 286. 314.

50 33.7 35.0 45.5 66.2 105. 142. 165. 198. 224.

60 15.0 17.6 22.2 38.0 69.0 107. 119. 140. 157.

70 7.27 9.01 14.2 18.0 36.8 72.2 89.2 102. 115.

75 5.64 7.30 10.2 14.3 28.8 62.0 70.0 80.0 92.1

80 4.50 5.64 7.64 11.0 21.0 49.8 55.8 59.4 67.9

90 2.41 3.38 4.66 6.98 13.6 29.0 33.7 39.6 43.0

95 1.43 2.42 3.45 5.08 11.0 19.6 24.9 30.4 39.3

98 0.81 1.62 2.66 3.68 7.56 15.2 18.3 25.5 35.1

99 0.53 1.46 2.28 3.25 7.00 13.0 17.8 23.2 34.0

7-day mean streamflow (ft3/s) that was equaled or exceeded the indicated percentage of time at APEE level

APEE 98 95 90 80 50 20 10 5 2

1 648. 835. 1150. 1240. 1750. 2290. 2640. 2920. 3380.

2 624. 745. 811. 1040. 1350. 1570. 1780. 1990. 2520.

5 546. 600. 673. 807. 972. 1200. 1310. 1390. 1950.

10 389. 416. 452. 560. 724. 884. 1010. 1080. 1120.

20 204. 258. 279. 318. 463. 588. 664. 742. 808.

25 140. 187. 220. 259. 373. 487. 585. 637. 740.

30 105. 149. 158. 202. 301. 421. 478. 544. 657.

40 58.3 77.2 89.6 120. 187. 283. 344. 405. 503.

50 30.9 37.3 48.8 74.8 129. 194. 243. 294. 362.

60 13.3 17.2 21.0 39.0 80.7 133. 165. 202. 260.

70 7.90 9.80 14.0 18.9 42.4 92.9 106. 136. 161.

75 6.15 7.91 11.2 15.9 33.1 80.7 91.8 114. 126.

80 4.93 5.98 8.50 11.0 24.1 62.2 76.0 80.9 100.

90 2.94 4.09 5.36 7.23 15.7 33.5 39.6 44.4 49.8

95 2.10 2.80 3.90 5.66 12.3 21.8 28.9 37.9 42.5

98 1.54 2.04 3.24 4.30 9.04 17.9 24.0 30.2 39.2

99 0.97 1.89 2.65 3.91 8.24 15.3 21.2 26.3 37.6

Appendix 4 99

Appendix 4. Annual Seasonal-Period Flow-Duration Results for Sites with 

Streamflows that have No or Minimal Regulation
100 Methods for Estimating Selected Low-Flow Statistics and Development of Annual Flow-Duration Statistics for Ohio

03089500 Mill Creek near Berlin Center, Ohio

Years analyzed = 30

Climatic year range = 1941–70

[APEE, annual percentage equaled or exceeded; ft3/s, cubic foot per second; Sep, September; Nov, November]

Sep–Nov daily mean streamflow (ft3/s) that was equaled or exceeded the indicated percentage of time at APEE level

APEE 95 90 80 70 50 30 20 10 5

1 2.24 2.80 8.78 10.0 22.5 46.8 83.8 141. 373.

2 1.51 1.92 5.62 7.84 16.0 30.8 59.9 122. 325.

5 1.08 1.30 2.58 4.22 6.97 14.2 23.7 46.0 76.8

10 0.94 1.00 1.52 2.60 3.87 7.55 13.0 28.7 31.1

20 0.66 0.81 1.02 1.76 2.48 3.38 5.62 15.2 18.9

25 0.60 0.80 0.90 1.60 2.05 2.70 4.34 11.4 16.0

30 0.56 0.68 0.72 1.39 1.80 2.27 3.77 9.09 12.4

40 0.46 0.50 0.64 0.93 1.32 1.68 2.38 4.88 7.56

50 0.35 0.40 0.60 0.73 1.15 1.37 1.84 3.42 5.19

60 0.30 0.30 0.42 0.59 0.90 1.16 1.38 2.25 3.29

70 0.20 0.30 0.31 0.43 0.60 0.81 1.05 1.38 2.32

75 0.16 0.20 0.30 0.40 0.55 0.70 0.98 1.29 2.25

80 0.16 0.20 0.21 0.40 0.50 0.60 0.89 1.28 1.85

90 0.10 0.10 0.20 0.29 0.35 0.41 0.58 0.88 1.47

95 0.06 0.10 0.11 0.20 0.30 0.40 0.50 0.77 1.31

98 0.00 0.00 0.10 0.18 0.28 0.30 0.40 0.76 1.26

99 0.00 0.00 0.10 0.10 0.20 0.30 0.40 0.68 1.21

03092000 Kale Creek near Pricetown, Ohio

Years analyzed = 52

Climatic year range = 1941–92

[APEE, annual percentage equaled or exceeded; ft3/s, cubic foot per second; Sep, September; Nov, November]

Sep–Nov daily mean streamflow (ft3/s) that was equaled or exceeded the indicated percentage of time at APEE level

APEE 98 95 90 80 50 20 10 5 2

1 0.52 0.93 1.61 11.0 114. 326. 446. 689. 789.

2 0.43 0.85 1.49 8.98 70.7 202. 328. 512. 639.

5 0.35 0.58 0.98 4.52 29.5 103. 120. 185. 228.

10 0.31 0.40 0.78 2.46 11.3 39.7 70.0 96.3 140.

20 0.30 0.36 0.47 1.22 5.16 16.4 27.6 42.6 58.7

25 0.25 0.30 0.40 1.00 3.90 12.4 19.0 32.1 48.2

30 0.20 0.27 0.36 0.76 2.91 8.88 16.3 26.2 34.8

40 0.10 0.19 0.24 0.50 1.91 5.12 11.1 14.9 22.6

50 0.05 0.13 0.20 0.37 1.30 3.88 8.50 11.0 16.8

60 0.04 0.10 0.12 0.26 0.88 3.31 6.71 9.28 13.6

70 0.00 0.09 0.10 0.20 0.54 2.04 4.10 7.50 10.8

75 0.00 0.07 0.10 0.20 0.40 1.74 3.34 6.98 9.76

80 0.00 0.06 0.10 0.18 0.37 1.25 2.55 6.18 7.88

90 0.00 0.01 0.06 0.10 0.22 0.76 1.82 3.45 5.87

95 0.00 0.00 0.01 0.06 0.20 0.61 1.47 2.14 5.81

98 0.00 0.00 0.00 0.04 0.17 0.59 1.30 1.78 5.47

99 0.00 0.00 0.00 0.04 0.14 0.57 1.27 1.67 4.43
Appendix 4 101

03092090 West Branch Mahoning River near Ravenna, Ohio

Years analyzed = 28

Climatic year range = 1965–92

[APEE, annual percentage equaled or exceeded; ft3/s, cubic foot per second; Sep, September; Nov, November]

Sep–Nov daily mean streamflow (ft3/s) that was equaled or exceeded the indicated percentage of time at APEE level

APEE 95 90 80 70 50 30 20 10 5

1 17.6 24.7 58.0 89.1 158. 255. 330. 540. 1180.

2 17.2 22.3 42.0 69.7 88.3 208. 225. 355. 465.

5 12.6 16.6 23.9 30.4 51.7 98.6 143. 176. 212.

10 9.15 11.4 15.0 18.6 33.0 52.9 68.2 98.6 135.

20 5.09 6.97 8.97 12.0 17.0 26.3 33.1 42.4 52.7

25 4.24 6.18 7.42 11.7 14.0 20.6 24.2 27.6 38.5

30 3.90 5.49 6.08 8.82 11.0 16.4 18.1 22.7 29.0

40 2.64 3.64 4.36 5.45 8.79 10.4 15.0 16.9 24.2

50 1.36 2.79 3.08 4.36 6.80 7.56 9.60 14.4 19.1

60 1.05 2.05 2.60 3.57 4.63 5.83 7.35 12.2 15.6

70 0.78 1.49 2.21 2.73 3.64 4.40 5.74 10.6 13.2

75 0.71 1.39 1.94 2.37 3.20 3.81 5.10 9.73 12.2

80 0.64 1.33 1.63 2.15 2.77 3.35 4.76 8.94 11.4

90 0.49 0.98 1.22 1.40 2.05 2.70 4.16 6.02 9.25

95 0.45 0.95 1.00 1.18 1.60 2.10 2.96 4.10 4.82

98 0.41 0.82 0.88 0.99 1.39 1.93 2.54 3.32 4.62

99 0.39 0.74 0.83 0.93 1.30 1.93 2.50 3.08 4.40

03102950 Pymatuning Creek at Kinsman, Ohio

Years analyzed = 29

Climatic year range = 1965–93

[APEE, annual percentage equaled or exceeded; ft3/s, cubic foot per second; Sep, September; Nov, November]

Sep–Nov daily mean streamflow (ft3/s) that was equaled or exceeded the indicated percentage of time at APEE level

APEE 95 90 80 70 50 30 20 10 5

1 35.0 107. 146. 260. 443. 603. 723. 1070. 2280.

2 34.6 75.1 144. 240. 424. 559. 664. 923. 1730.

5 29.5 52.4 138. 197. 347. 464. 506. 682. 782.

10 25.3 44.8 93.2 135. 256. 290. 338. 445. 555.

20 19.0 33.2 48.2 72.2 101. 184. 208. 272. 393.

25 17.5 29.0 37.0 44.0 88.0 144. 169. 207. 282.

30 16.0 23.4 27.0 33.8 69.8 111. 150. 196. 265.

40 9.25 12.2 16.4 23.0 44.4 78.2 107. 139. 203.

50 5.95 7.80 11.0 14.0 24.0 41.0 83.0 93.0 157.

60 5.03 6.48 8.80 11.0 16.8 33.0 56.0 64.8 129.

70 4.28 5.20 6.22 7.90 11.0 28.0 39.0 56.0 103.

75 3.60 4.50 5.10 5.70 9.60 20.0 37.0 50.0 87.0

80 3.17 3.74 4.80 5.20 8.48 16.0 30.6 45.4 73.9

90 1.11 2.00 2.56 3.26 5.72 11.0 24.0 36.0 50.9

95 0.66 1.36 1.68 2.66 4.40 8.06 17.2 24.0 25.4

98 0.46 0.99 1.38 1.85 3.20 6.78 11.6 19.5 22.2

99 0.39 0.94 1.10 1.60 3.20 5.70 9.80 17.0 20.5
102 Methods for Estimating Selected Low-Flow Statistics and Development of Annual Flow-Duration Statistics for Ohio

03109500 Little Beaver Creek near East Liverpool, Ohio

Years analyzed = 94

Climatic year range = 1915–2008

[APEE, annual percentage equaled or exceeded; ft3/s, cubic foot per second; Sep, September; Nov, November]

Sep–Nov daily mean streamflow (ft3/s) that was equaled or exceeded the indicated percentage of time at APEE level

APEE 98 95 90 80 50 20 10 5 2

1 121. 157. 291. 394. 882. 2480. 3950. 6400. 14800.

2 97.7 138. 200. 334. 728. 2200. 3490. 4950. 8440.

5 68.7 87.8 140. 206. 449. 1320. 2140. 2880. 4040.

10 53.1 69.8 112. 159. 275. 803. 1340. 1460. 2670.

20 44.9 54.2 82.8 108. 186. 408. 787. 855. 1300.

25 42.5 50.3 71.5 94.0 160. 354. 638. 778. 1070.

30 39.7 47.3 66.1 82.4 142. 278. 551. 666. 958.

40 37.5 39.2 52.8 65.2 113. 220. 395. 512. 734.

50 33.7 35.8 45.5 59.0 96.5 199. 290. 416. 587.

60 28.8 33.0 39.9 49.0 80.4 159. 226. 379. 510.

70 26.7 31.6 34.3 43.6 68.5 129. 191. 321. 440.

75 25.1 29.8 32.5 42.0 58.5 112. 168. 310. 422.

80 24.0 29.1 31.1 38.4 53.2 102. 148. 299. 384.

90 21.1 24.8 26.6 32.0 46.5 82.8 132. 267. 337.

95 19.2 22.5 24.0 29.2 40.8 72.0 128. 199. 293.

98 18.2 21.4 22.0 27.0 38.2 64.5 122. 175. 254.

99 17.4 19.8 22.0 27.0 36.0 61.0 105. 144. 249.

03110000 Yellow Creek near Hammondsville, Ohio

Years analyzed = 68

Climatic year range = 1941–2008

[APEE, annual percentage equaled or exceeded; ft3/s, cubic foot per second; Sep, September; Nov, November]

Sep–Nov daily mean streamflow (ft3/s) that was equaled or exceeded the indicated percentage of time at APEE level

APEE 98 95 90 80 50 20 10 5 2

1 20.0 39.5 71.1 135. 313. 789. 1050. 1960. 5840.

2 16.8 35.8 62.6 97.8 243. 580. 798. 1290. 4290.

5 14.1 24.8 42.5 66.1 143. 368. 530. 706. 1160.

10 9.73 17.0 32.2 44.4 92.2 251. 292. 475. 839.

20 7.13 11.8 22.9 27.2 58.1 163. 197. 274. 320.

25 6.61 9.98 19.9 24.0 49.5 128. 171. 225. 286.

30 5.71 8.87 15.4 21.4 42.5 107. 140. 195. 241.

40 4.91 6.57 10.2 15.8 31.7 69.4 107. 164. 196.

50 4.20 5.45 8.37 12.8 26.0 56.4 93.8 131. 145.

60 3.50 4.64 6.14 9.30 19.9 38.4 74.2 105. 124.

70 2.38 4.03 4.76 7.07 15.8 31.4 59.9 88.9 106.

75 2.04 3.75 4.17 6.62 13.0 27.2 55.2 81.3 101.

80 1.71 3.14 3.70 5.18 12.0 25.2 48.0 74.2 89.5

90 1.13 2.09 2.48 4.26 9.03 20.3 31.0 59.6 69.3

95 0.88 1.81 1.99 3.48 7.67 16.2 28.0 49.8 62.7

98 0.88 1.48 1.88 2.92 6.65 13.9 26.1 47.9 59.4

99 0.88 1.44 1.80 2.68 6.35 13.2 26.1 46.9 57.5
Appendix 4 103

03110000 Yellow Creek at Hammondsville, Ohio

Years analyzed = 20

Climatic year range = 1915–34

[APEE, annual percentage equaled or exceeded; ft3/s, cubic foot per second; Sep, September; Nov, November]

Sep–Nov daily mean streamflow (ft3/s) that was equaled or exceeded the indicated percentage of time at APEE level

APEE 95 90 80 70 50 30 20 10 5

1 17.3 65.7 146. 181. 314. 1090. 1860. 4690. 7130.

2 13.3 64.4 98.3 153. 246. 789. 1660. 2600. 4220.

5 10.2 32.9 51.2 65.8 129. 404. 624. 1360. 2070.

10 6.75 20.4 41.0 49.2 86.1 261. 327. 689. 1010.

20 4.35 11.9 26.8 30.3 54.1 91.8 197. 427. 592.

25 3.63 9.20 21.6 24.6 38.5 76.3 94.0 332. 528.

30 3.63 8.98 18.9 21.2 31.7 64.7 89.0 288. 393.

40 3.01 7.13 12.4 15.9 24.7 52.5 73.6 173. 321.

50 1.83 2.57 9.14 12.5 22.0 35.6 67.8 124. 269.

60 1.57 2.12 7.19 9.26 17.9 26.4 57.2 82.0 224.

70 1.17 1.59 4.45 7.47 14.0 20.0 48.7 60.4 196.

75 1.01 1.39 4.30 6.52 13.0 18.0 40.4 57.2 167.

80 0.81 1.20 4.24 6.00 12.2 16.3 35.4 55.0 167.

90 0.54 1.01 3.25 5.24 10.1 13.7 23.6 52.1 138.

95 0.42 0.83 3.06 3.98 9.15 12.0 20.5 48.5 116.

98 0.22 0.63 2.00 2.49 7.13 10.5 17.4 44.7 84.6

99 0.22 0.55 1.28 2.03 7.00 10.0 16.6 42.0 45.8

03111500 Short Creek near Dillonvale, Ohio

Years analyzed = 68

Climatic year range = 1941–2008

[APEE, annual percentage equaled or exceeded; ft3/s, cubic foot per second; Sep, September; Nov, November]

Sep–Nov daily mean streamflow (ft3/s) that was equaled or exceeded the indicated percentage of time at APEE level

APEE 98 95 90 80 50 20 10 5 2

1 48.9 67.5 94.3 118. 285. 468. 972. 1870. 3230.

2 37.9 54.7 73.3 97.2 177. 339. 635. 1580. 2790.

5 25.6 38.2 56.9 64.0 114. 225. 359. 555. 994.

10 19.6 31.3 39.2 46.1 82.3 159. 235. 284. 499.

20 16.9 24.8 27.0 32.8 55.9 104. 170. 200. 289.

25 16.5 23.0 25.0 30.0 51.0 93.4 150. 187. 233.

30 15.1 20.4 23.0 27.3 47.8 82.8 134. 149. 214.

40 14.1 18.6 20.9 24.0 40.6 71.2 111. 130. 184.

50 13.4 17.5 19.0 22.0 35.5 63.0 100. 106. 148.

60 12.8 14.9 18.0 20.0 31.8 53.2 80.2 96.9 132.

70 12.0 13.9 16.9 18.0 29.5 47.1 69.7 88.6 120.

75 11.0 12.4 16.0 18.0 28.0 43.4 66.0 84.0 116.

80 9.35 11.9 14.9 16.8 25.7 40.5 59.5 81.0 113.

90 6.25 9.96 12.9 14.0 22.5 35.8 52.8 73.5 106.

95 4.57 8.10 11.5 13.0 21.0 32.8 49.7 71.1 97.2

98 3.64 7.47 9.75 12.7 19.3 31.0 47.5 64.2 82.9

99 3.26 6.35 9.75 12.0 18.5 30.8 45.1 62.2 79.5
104 Methods for Estimating Selected Low-Flow Statistics and Development of Annual Flow-Duration Statistics for Ohio

03111548 Wheeling Creek below Blaine, Ohio

Years analyzed = 25

Climatic year range = 1983–2008

[APEE, annual percentage equaled or exceeded; ft3/s, cubic foot per second; Sep, September; Nov, November]

Sep–Nov daily mean streamflow (ft3/s) that was equaled or exceeded the indicated percentage of time at APEE level

APEE 95 90 80 70 50 30 20 10 5

1 54.1 90.6 142. 194. 243. 475. 554. 1550. 3590.

2 48.4 56.3 107. 136. 202. 313. 447. 901. 2420.

5 39.4 43.6 76.3 83.8 131. 205. 234. 535. 935.

10 33.4 34.9 41.8 60.7 98.6 130. 168. 281. 429.

20 24.9 28.3 31.7 44.4 68.0 85.9 106. 142. 224.

25 23.6 26.2 28.6 40.4 64.0 77.6 92.2 105. 180.

30 22.9 24.6 27.5 38.1 58.8 68.4 73.8 96.4 164.

40 21.3 22.6 23.6 26.8 44.2 49.5 64.2 84.1 142.

50 18.6 20.0 22.0 24.8 36.0 43.4 59.4 73.6 123.

60 15.5 19.0 21.0 23.6 29.6 38.0 53.0 68.6 106.

70 13.9 16.6 18.4 20.8 26.0 35.8 44.9 63.0 94.8

75 11.9 14.6 18.4 20.0 24.0 34.6 40.4 61.2 92.1

80 10.9 14.0 15.6 18.8 24.0 31.4 37.3 57.6 89.9

90 8.01 10.7 14.4 17.8 20.0 26.6 34.4 50.3 78.6

95 7.74 10.6 13.4 16.6 20.0 24.4 31.4 36.6 62.2

98 7.33 9.98 12.9 13.8 18.8 23.4 30.7 35.2 56.6

99 7.33 9.84 12.2 13.8 18.0 23.4 30.0 35.2 55.4

03114000 Captina Creek at Armstrongs Mills, Ohio

Years analyzed = 54

Climatic year range = 1926–2002

[APEE, annual percentage equaled or exceeded; ft3/s, cubic foot per second; Sep, September; Nov, November]

Sep–Nov daily mean streamflow (ft3/s) that was equaled or exceeded the indicated percentage of time at APEE level

APEE 98 95 90 80 50 20 10 5 2

1 15.0 66.3 88.0 197. 423. 1340. 2050. 3830. 4950.

2 6.58 38.9 64.7 117. 333. 689. 1180. 2610. 4610.

5 3.46 18.8 40.9 60.8 167. 417. 615. 1260. 1980.

10 2.34 12.6 22.8 38.0 88.5 253. 361. 543. 720.

20 1.46 5.22 11.8 21.6 51.8 124. 206. 287. 395.

25 1.18 4.90 9.55 18.0 42.5 102. 153. 239. 349.

30 1.15 4.15 8.55 15.0 35.8 80.0 128. 204. 278.

40 0.71 2.66 4.65 9.84 21.3 47.0 85.2 141. 199.

50 0.42 1.20 2.80 6.90 16.5 32.0 65.5 124. 156.

60 0.11 0.65 1.94 5.24 11.4 24.0 56.4 105. 125.

70 0.10 0.33 1.44 3.40 7.82 19.0 46.1 90.5 109.

75 0.10 0.25 1.21 2.30 6.85 17.0 42.5 83.5 101.

80 0.01 0.10 0.64 1.64 6.04 16.4 39.0 76.3 89.8

90 0.00 0.07 0.21 0.92 4.59 11.0 29.3 63.1 70.5

95 0.00 0.00 0.12 0.37 3.64 8.60 24.0 46.0 59.0

98 0.00 0.00 0.00 0.28 2.72 7.44 18.7 38.0 54.4

99 0.00 0.00 0.00 0.28 2.15 7.10 18.0 37.8 52.9
Appendix 4 105

03115400 Little Muskingum River at Bloomfield, Ohio

Years analyzed = 37

Climatic year range = 1958–2008

[APEE, annual percentage equaled or exceeded; ft3/s, cubic foot per second; Sep, September; Nov, November]

Sep–Nov daily mean streamflow (ft3/s) that was equaled or exceeded the indicated percentage of time at APEE level

APEE 95 90 80 70 50 30 20 10 5

1 45.1 84.0 339. 403. 900. 1280. 2190. 5110. 8720.

2 42.2 71.1 210. 330. 655. 940. 1690. 4550. 5760.

5 20.6 44.5 103. 146. 262. 493. 932. 1290. 2260.

10 15.1 25.3 32.5 79.8 140. 266. 462. 604. 945.

20 4.67 6.07 13.2 36.4 68.2 130. 227. 345. 563.

25 3.26 4.68 9.84 28.8 60.0 103. 191. 281. 420.

30 2.65 4.16 8.20 20.0 47.4 79.8 156. 226. 339.

40 1.25 2.14 5.73 12.0 28.6 49.7 106. 160. 246.

50 0.95 1.74 4.76 6.88 20.0 33.6 63.6 118. 196.

60 0.67 1.00 3.13 4.94 14.8 21.5 30.2 90.7 143.

70 0.32 0.72 1.99 3.08 9.64 14.4 20.0 65.3 114.

75 0.30 0.60 1.32 2.64 8.20 11.8 19.2 53.4 102.

80 0.29 0.48 0.96 1.95 5.22 9.89 18.4 48.3 93.1

90 0.18 0.31 0.60 1.15 3.50 7.02 13.0 37.9 64.0

95 0.08 0.11 0.39 0.81 2.60 4.77 7.16 31.8 46.0

98 0.03 0.09 0.32 0.65 1.75 3.78 5.98 27.0 37.3

99 0.02 0.09 0.31 0.54 1.50 3.06 5.50 25.8 36.2

03117500 Sandy Creek at Waynesburg, Ohio

Years analyzed = 70

Climatic year range = 1939–2008

[APEE, annual percentage equaled or exceeded; ft3/s, cubic foot per second; Sep, September; Nov, November]

Sep–Nov daily mean streamflow (ft3/s) that was equaled or exceeded the indicated percentage of time at APEE level

APEE 98 95 90 80 50 20 10 5 2

1 36.9 45.8 95.7 234. 459. 980. 1720. 2590. 4460.

2 34.8 40.5 86.7 168. 435. 819. 1470. 2130. 3900.

5 27.8 38.1 61.6 110. 238. 652. 952. 1400. 2210.

10 24.6 36.5 44.0 79.6 166. 409. 617. 888. 1240.

20 22.6 33.8 38.0 53.0 112. 257. 408. 553. 679.

25 22.2 31.7 36.0 50.2 102. 228. 355. 433. 513.

30 21.8 31.1 35.0 44.2 93.7 206. 309. 391. 466.

40 21.2 27.1 31.0 37.6 79.5 160. 229. 332. 353.

50 20.4 25.6 28.0 34.6 68.0 130. 186. 272. 303.

60 19.0 24.3 26.1 33.0 54.0 108. 167. 234. 264.

70 17.1 22.8 24.6 30.0 46.3 82.4 131. 183. 235.

75 15.9 21.0 23.1 28.0 44.0 78.6 119. 164. 226.

80 15.5 20.7 23.1 26.7 42.0 72.6 116. 154. 213.

90 14.6 19.2 21.0 24.0 36.2 61.4 77.8 120. 188.

95 13.7 17.0 19.0 21.9 34.5 54.9 71.9 116. 152.

98 12.4 16.0 19.0 21.1 33.3 51.8 70.6 109. 138.

99 12.0 15.6 18.0 20.4 32.5 50.8 68.5 108. 134.
106 Methods for Estimating Selected Low-Flow Statistics and Development of Annual Flow-Duration Statistics for Ohio

03119000 Sandy Creek at Sandyville, Ohio

Years analyzed = 24

Climatic year range = 1923–46

[APEE, annual percentage equaled or exceeded; ft3/s, cubic foot per second; Sep, September; Nov, November]

Sep–Nov daily mean streamflow (ft3/s) that was equaled or exceeded the indicated percentage of time at APEE level

APEE 95 90 80 70 50 30 20 10 5

1 132. 238. 457. 597. 914. 1720. 2030. 3170. 4500.

2 130. 225. 420. 445. 767. 1580. 1940. 3040. 4040.

5 115. 141. 230. 332. 401. 743. 1180. 1480. 2460.

10 103. 122. 165. 236. 295. 490. 682. 984. 1720.

20 96.2 105. 142. 150. 206. 301. 380. 629. 1040.

25 93.8 102. 128. 141. 193. 244. 282. 540. 893.

30 92.2 100. 123. 134. 180. 215. 252. 488. 840.

40 88.8 93.2 113. 122. 151. 187. 213. 405. 660.

50 86.5 90.5 103. 116. 131. 161. 200. 330. 572.

60 78.0 84.0 95.0 106. 123. 153. 189. 252. 482.

70 72.5 80.6 88.0 99.4 114. 143. 162. 196. 415.

75 69.8 79.0 86.0 95.0 109. 138. 159. 170. 367.

80 67.5 75.1 85.0 89.3 108. 128. 138. 151. 323.

90 58.8 69.7 80.2 82.1 99.9 109. 124. 133. 269.

95 54.8 66.0 75.6 77.5 93.7 103. 117. 128. 239.

98 49.1 59.8 68.4 73.7 84.9 97.2 110. 121. 207.

99 46.0 58.5 65.0 72.0 79.0 95.0 99.0 110. 120.

03125000 Home Creek near New Philadelphia, Ohio

Years analyzed = 43

Climatic year range = 1937–79

[APEE, annual percentage equaled or exceeded; ft3/s, cubic foot per second; Sep, September; Nov, November]

Sep–Nov daily mean streamflow (ft3/s) that was equaled or exceeded the indicated percentage of time at APEE level

APEE 95 90 80 70 50 30 20 10 5

1 0.32 0.54 0.93 1.24 3.20 7.80 12.6 18.2 23.0

2 0.15 0.42 0.52 0.87 2.04 5.37 9.01 10.6 13.9

5 0.04 0.11 0.29 0.49 0.94 2.99 3.53 4.73 5.03

10 0.01 0.07 0.12 0.30 0.50 1.58 2.08 2.68 3.12

20 0.00 0.02 0.08 0.17 0.27 0.71 1.17 1.44 1.49

25 0.00 0.00 0.05 0.10 0.22 0.56 0.97 1.20 1.28

30 0.00 0.00 0.04 0.10 0.20 0.46 0.73 1.03 1.17

40 0.00 0.00 0.02 0.04 0.12 0.29 0.50 0.70 0.87

50 0.00 0.00 0.00 0.03 0.10 0.15 0.40 0.56 0.69

60 0.00 0.00 0.00 0.02 0.08 0.12 0.25 0.41 0.56

70 0.00 0.00 0.00 0.00 0.04 0.10 0.14 0.31 0.45

75 0.00 0.00 0.00 0.00 0.03 0.10 0.10 0.26 0.43

80 0.00 0.00 0.00 0.00 0.02 0.08 0.10 0.23 0.41

90 0.00 0.00 0.00 0.00 0.01 0.06 0.10 0.12 0.20

95 0.00 0.00 0.00 0.00 0.00 0.04 0.07 0.10 0.13

98 0.00 0.00 0.00 0.00 0.00 0.03 0.05 0.10 0.12

99 0.00 0.00 0.00 0.00 0.00 0.02 0.04 0.10 0.12
Appendix 4 107

03130500 Touby Run at Mansfield, Ohio

Years analyzed = 32

Climatic year range = 1946–77

[APEE, annual percentage equaled or exceeded; ft3/s, cubic foot per second; Sep, September; Nov, November]

Sep–Nov daily mean streamflow (ft3/s) that was equaled or exceeded the indicated percentage of time at APEE level

APEE 95 90 80 70 50 30 20 10 5

1 1.75 3.64 6.06 7.95 14.0 44.0 57.0 90.9 113.

2 0.84 2.39 4.20 5.02 13.2 27.5 32.2 44.1 65.7

5 0.63 1.19 2.17 3.12 6.65 9.20 15.2 19.7 23.7

10 0.47 0.89 1.36 1.89 3.74 5.03 7.58 12.0 14.4

20 0.30 0.53 0.86 1.28 1.90 2.50 3.70 4.73 7.71

25 0.27 0.50 0.76 1.27 1.60 1.90 2.32 3.28 6.35

30 0.27 0.34 0.71 0.98 1.37 1.60 1.84 2.75 5.04

40 0.20 0.30 0.70 0.79 1.05 1.31 1.48 2.28 3.09

50 0.20 0.20 0.50 0.54 0.93 1.11 1.24 1.67 2.11

60 0.20 0.20 0.42 0.50 0.80 0.97 1.22 1.37 1.62

70 0.17 0.20 0.30 0.40 0.65 0.77 0.98 1.27 1.43

75 0.17 0.20 0.30 0.40 0.57 0.76 0.86 1.14 1.33

80 0.10 0.14 0.20 0.29 0.50 0.62 0.83 1.03 1.23

90 0.09 0.10 0.20 0.24 0.40 0.50 0.62 0.78 1.00

95 0.08 0.10 0.20 0.20 0.38 0.50 0.51 0.66 0.81

98 0.05 0.10 0.11 0.20 0.30 0.41 0.50 0.53 0.79

99 0.04 0.09 0.10 0.19 0.30 0.40 0.50 0.50 0.73

03134000 Jerome Fork at Jeromeville, Ohio

Years analyzed = 24

Climatic year range = 1925–48

[APEE, annual percentage equaled or exceeded; ft3/s, cubic foot per second; Sep, September; Nov, November]

Sep–Nov daily mean streamflow (ft3/s) that was equaled or exceeded the indicated percentage of time at APEE level

APEE 95 90 80 70 50 30 20 10 5

1 20.0 29.0 71.0 119. 224. 505. 658. 952. 1090.

2 18.1 27.7 35.7 72.8 155. 361. 462. 694. 1050.

5 10.9 15.3 21.4 35.1 60.4 209. 262. 437. 633.

10 7.68 10.5 13.8 17.0 32.2 86.3 167. 221. 298.

20 6.28 8.00 9.10 11.8 17.8 42.0 56.0 111. 160.

25 6.13 7.65 8.00 10.2 15.5 29.5 42.0 90.0 140.

30 5.68 7.20 7.80 9.95 14.5 24.5 37.0 79.9 114.

40 5.05 6.25 6.80 8.70 12.1 17.2 28.0 67.7 88.0

50 4.88 5.50 6.00 7.40 10.0 14.0 22.0 50.0 63.8

60 4.05 4.50 5.40 6.45 8.52 11.9 19.0 38.9 47.8

70 3.63 3.90 4.80 5.75 7.60 10.9 15.0 26.9 36.2

75 3.63 3.90 4.80 5.30 6.80 10.7 13.0 23.3 31.4

80 3.43 3.60 4.70 5.20 6.20 10.0 12.0 20.9 27.4

90 3.05 3.45 4.10 4.45 5.65 7.65 11.0 14.0 20.6

95 2.35 2.90 3.68 3.91 4.45 6.88 9.20 11.3 15.3

98 2.23 2.70 3.20 3.45 4.43 6.20 7.70 9.82 11.8

99 2.10 2.70 3.20 3.45 4.35 6.20 7.70 9.40 9.85
108 Methods for Estimating Selected Low-Flow Statistics and Development of Annual Flow-Duration Statistics for Ohio

03136500 Kokosing River at Mount Vernon, Ohio

Years analyzed = 57

Climatic year range = 1953–2009

[APEE, annual percentage equaled or exceeded; ft3/s, cubic foot per second; Sep, September; Nov, November]

Sep–Nov daily mean streamflow (ft3/s) that was equaled or exceeded the indicated percentage of time at APEE level

APEE 98 95 90 80 50 20 10 5 2

1 24.5 40.5 56.0 90.6 325. 1090. 1500. 2220. 5130.

2 24.5 31.4 53.0 80.3 292. 769. 1290. 1900. 3720.

5 22.7 26.9 42.3 57.0 187. 412. 912. 1310. 1470.

10 21.3 24.8 37.6 48.3 126. 234. 418. 866. 962.

20 21.2 22.9 31.6 40.7 83.8 143. 216. 330. 428.

25 20.2 22.8 30.0 38.6 74.0 123. 170. 252. 357.

30 20.2 22.8 29.0 37.2 66.8 104. 141. 188. 310.

40 19.2 22.7 28.0 32.6 48.0 85.2 121. 141. 247.

50 18.3 21.8 24.8 30.0 43.0 71.0 93.2 123. 205.

60 17.3 20.8 23.4 28.0 39.0 62.9 87.2 106. 178.

70 15.8 18.8 21.0 25.8 35.6 59.6 76.9 97.0 153.

75 15.2 17.8 19.8 25.0 34.0 56.4 71.6 93.1 139.

80 13.7 15.9 19.8 24.0 33.0 54.4 64.6 87.3 128.

90 12.3 14.0 18.0 21.1 31.0 49.5 57.6 72.1 106.

95 11.5 14.0 16.7 19.6 29.0 45.8 52.2 59.2 77.0

98 9.90 13.0 15.6 17.9 27.0 43.5 49.4 53.2 70.3

99 9.47 13.0 14.8 17.6 27.0 43.2 49.2 52.3 69.3

03137000 Kokosing River at Millwood, Ohio

Years analyzed = 53

Climatic year range = 1921–73

[APEE, annual percentage equaled or exceeded; ft3/s, cubic foot per second; Sep, September; Nov, November]

Sep–Nov daily mean streamflow (ft3/s) that was equaled or exceeded the indicated percentage of time at APEE level

APEE 98 95 90 80 50 20 10 5 2

1 55.8 86.0 127. 185. 769. 1820. 3620. 5430. 7800.

2 55.6 85.0 105. 153. 618. 1470. 2680. 4610. 6760.

5 53.0 65.4 84.2 110. 342. 780. 1520. 2470. 3250.

10 52.2 59.9 71.9 90.5 218. 438. 640. 1560. 1950.

20 50.0 53.6 63.9 79.6 144. 276. 368. 800. 1080.

25 49.1 52.1 61.8 76.4 124. 223. 281. 636. 782.

30 48.2 50.7 61.4 74.0 113. 191. 247. 533. 732.

40 45.2 48.0 59.8 70.9 96.2 156. 214. 334. 614.

50 43.2 46.0 56.8 66.2 84.0 123. 154. 267. 577.

60 42.2 44.0 52.4 63.2 81.0 111. 133. 229. 492.

70 39.2 43.2 49.4 58.6 78.0 100. 120. 211. 307.

75 38.2 42.8 47.2 57.8 77.0 95.6 117. 193. 274.

80 38.1 39.7 45.6 55.6 74.0 92.0 113. 172. 248.

90 37.0 37.7 41.8 51.6 69.0 85.3 101. 142. 180.

95 35.6 36.0 41.4 49.6 66.0 80.2 98.2 123. 130.

98 34.2 36.0 39.8 46.8 64.0 78.0 96.1 107. 126.

99 34.2 36.0 38.0 46.0 64.0 77.2 95.2 106. 121.
Appendix 4 109

03139000 Killbuck Creek at Killbuck, Ohio

Years analyzed = 79

Climatic year range = 1930–2008

[APEE, annual percentage equaled or exceeded; ft3/s, cubic foot per second; Sep, September; Nov, November]

Sep–Nov daily mean streamflow (ft3/s) that was equaled or exceeded the indicated percentage of time at APEE level

APEE 98 95 90 80 50 20 10 5 2

1 47.2 104. 160. 273. 681. 1120. 1570. 2210. 4880.

2 45.1 93.9 124. 229. 577. 955. 1450. 2120. 3620.

5 43.2 61.8 89.2 144. 367. 663. 1070. 1850. 2820.

10 39.2 51.6 70.8 123. 224. 481. 752. 1300. 1720.

20 37.0 48.0 59.6 93.8 140. 332. 564. 804. 1050.

25 35.6 47.0 57.0 77.0 128. 284. 490. 640. 873.

30 35.0 47.0 53.0 71.4 122. 223. 338. 543. 693.

40 32.3 44.0 51.0 64.0 100. 170. 299. 434. 542.

50 30.4 43.0 47.0 62.0 89.0 151. 224. 382. 436.

60 29.2 38.0 44.0 53.0 82.0 134. 198. 300. 378.

70 28.0 33.0 42.0 50.6 76.0 118. 168. 261. 348.

75 26.6 31.0 40.0 47.0 72.0 107. 153. 245. 334.

80 26.6 30.4 38.0 45.0 71.0 99.8 144. 235. 321.

90 25.2 30.0 35.2 42.0 61.8 92.0 125. 178. 275.

95 24.2 28.6 34.0 38.6 54.0 87.4 114. 157. 250.

98 24.1 27.5 33.0 37.0 52.8 83.5 107. 153. 232.

99 23.6 27.0 32.0 37.0 52.0 82.0 107. 149. 222.

03140000 Mill Creek near Coshocton, Ohio

Years analyzed = 72

Climatic year range = 1937–2008

[APEE, annual percentage equaled or exceeded; ft3/s, cubic foot per second; Sep, September; Nov, November]

Sep–Nov daily mean streamflow (ft3/s) that was equaled or exceeded the indicated percentage of time at APEE level

APEE 98 95 90 80 50 20 10 5 2

1 1.92 5.17 7.81 23.2 65.0 167. 408. 556. 1400.

2 1.34 4.38 7.32 15.3 49.8 107. 266. 350. 430.

5 0.71 2.28 2.90 7.84 22.2 51.5 103. 134. 192.

10 0.44 1.50 1.93 4.46 11.9 29.0 55.0 84.1 124.

20 0.30 0.74 1.34 2.34 6.80 18.4 36.1 44.8 51.3

25 0.30 0.60 1.20 2.00 5.80 16.4 28.4 36.4 43.8

30 0.25 0.53 1.13 1.85 5.04 12.3 23.8 30.4 37.3

40 0.20 0.42 0.82 1.41 3.22 9.24 16.5 24.4 30.6

50 0.10 0.36 0.50 1.20 2.50 7.20 13.1 18.3 23.6

60 0.10 0.27 0.46 0.95 2.09 5.46 12.1 15.2 19.1

70 0.10 0.20 0.30 0.69 1.60 4.13 8.69 12.0 16.2

75 0.10 0.17 0.26 0.63 1.30 3.74 6.97 11.3 15.2

80 0.10 0.10 0.24 0.54 1.12 2.87 5.66 9.93 14.1

90 0.10 0.10 0.17 0.33 0.93 2.04 3.87 8.47 11.6

95 0.10 0.10 0.10 0.25 0.72 1.90 3.48 8.11 10.8

98 0.05 0.10 0.10 0.20 0.58 1.72 3.11 7.87 9.39

99 0.05 0.10 0.10 0.20 0.52 1.62 2.94 7.51 9.02
110 Methods for Estimating Selected Low-Flow Statistics and Development of Annual Flow-Duration Statistics for Ohio

03144000 Wakatomika Creek near Frazeysburg, Ohio

Years analyzed = 73

Climatic year range = 1936–2008

[APEE, annual percentage equaled or exceeded; ft3/s, cubic foot per second; Sep, September; Nov, November]

Sep–Nov daily mean streamflow (ft3/s) that was equaled or exceeded the indicated percentage of time at APEE level

APEE 98 95 90 80 50 20 10 5 2

1 12.9 18.1 36.0 97.6 387. 803. 1320. 1750. 5480.

2 10.9 14.6 32.1 89.1 248. 609. 949. 1280. 3460.

5 9.06 12.0 26.9 45.1 126. 310. 561. 656. 923.

10 8.06 11.0 20.2 26.4 69.2 196. 278. 355. 420.

20 7.10 9.20 13.9 19.4 45.2 111. 150. 192. 218.

25 6.64 9.02 11.8 17.0 40.0 92.0 136. 159. 182.

30 6.52 8.56 10.8 16.4 34.0 83.5 118. 141. 159.

40 6.05 7.55 9.88 13.2 26.0 56.7 85.3 103. 121.

50 5.24 6.28 8.56 11.0 21.0 48.2 69.0 88.9 101.

60 4.82 5.73 7.96 10.0 17.8 37.7 53.6 70.8 88.7

70 4.03 5.19 6.72 8.70 13.6 31.0 45.0 52.2 80.0

75 3.59 4.79 5.88 8.18 12.0 27.0 37.8 48.5 74.8

80 3.44 4.32 5.33 7.53 11.0 24.0 32.6 45.7 68.4

90 2.86 3.64 4.72 6.77 9.48 19.6 25.3 32.2 59.9

95 2.75 3.20 4.18 5.99 8.62 17.7 21.2 29.4 51.9

98 2.65 3.20 3.74 5.48 8.08 15.9 19.1 27.5 47.4

99 2.65 3.20 3.48 5.20 8.00 15.2 18.6 25.9 46.6

03146000 North Fork Licking River at Utica, Ohio

Years analyzed = 22

Climatic year range = 1939–81

[APEE, annual percentage equaled or exceeded; ft3/s, cubic foot per second; Sep, September; Nov, November]

Sep–Nov daily mean streamflow (ft3/s) that was equaled or exceeded the indicated percentage of time at APEE level

APEE 95 90 80 70 50 30 20 10 5

1 5.43 19.4 75.6 270. 413. 829. 1520. 3000. 6200.

2 5.35 17.2 62.5 187. 303. 621. 1160. 2190. 3220.

5 4.53 10.1 41.5 68.1 138. 236. 332. 1070. 1530.

10 4.31 6.32 24.0 43.2 83.7 144. 150. 406. 531.

20 4.00 5.38 15.2 22.7 44.7 72.4 80.7 166. 218.

25 3.66 5.02 11.0 19.5 36.5 56.3 66.4 135. 181.

30 3.63 4.82 9.03 17.6 30.1 47.0 51.1 120. 159.

40 3.52 4.41 7.24 13.8 22.2 32.3 35.8 89.3 113.

50 3.23 4.06 6.56 9.09 13.0 20.0 25.6 66.7 93.9

60 2.83 3.66 5.95 8.08 10.4 16.1 18.0 56.6 81.0

70 2.36 3.13 5.45 6.42 8.45 12.3 15.4 46.4 67.1

75 2.09 2.83 5.00 5.94 7.90 10.3 14.4 30.7 61.2

80 1.89 2.61 4.58 5.49 7.05 9.87 12.6 19.7 53.3

90 1.44 2.32 3.55 4.20 5.95 8.31 9.58 17.2 47.4

95 1.26 2.19 3.12 3.45 5.18 6.68 8.59 15.9 35.3

98 1.11 2.08 2.60 2.98 4.73 6.46 7.34 11.4 26.2

99 0.96 2.08 2.60 2.98 4.65 6.43 7.04 11.4 24.7
Appendix 4 111

03146500 Licking River near Newark, Ohio

Years analyzed = 69

Climatic year range = 1939–2008

[APEE, annual percentage equaled or exceeded; ft3/s, cubic foot per second; Sep, September; Nov, November]

Sep–Nov daily mean streamflow (ft3/s) that was equaled or exceeded the indicated percentage of time at APEE level

APEE 98 95 90 80 50 20 10 5 2

1 67.8 126. 201. 299. 1700. 3440. 5180. 7240. 13100.

2 60.7 116. 200. 265. 1270. 2600. 4830. 6020. 12200.

5 55.7 86.3 137. 224. 625. 1410. 2940. 3780. 4880.

10 51.0 63.7 77.2 188. 378. 869. 1150. 2140. 3160.

20 44.4 54.6 64.6 110. 249. 544. 733. 1130. 1270.

25 44.4 51.5 62.0 99.0 205. 416. 622. 793. 1110.

30 42.4 50.7 62.0 83.0 153. 315. 518. 634. 972.

40 42.4 48.0 57.0 68.4 108. 209. 367. 523. 714.

50 40.8 47.0 55.0 66.0 93.0 167. 268. 395. 538.

60 40.4 45.5 54.0 62.0 81.8 151. 226. 317. 453.

70 40.0 42.5 53.0 58.0 77.0 141. 182. 260. 394.

75 37.4 42.0 52.0 56.0 75.0 127. 162. 212. 352.

80 36.9 42.0 52.0 54.4 70.8 108. 146. 186. 316.

90 34.0 39.5 49.0 53.0 66.2 93.4 125. 158. 271.

95 32.0 38.6 48.4 51.2 65.0 92.0 107. 150. 232.

98 31.7 36.0 43.0 50.0 62.8 87.0 99.7 142. 214.

99 30.0 36.0 43.0 49.0 62.0 87.0 98.0 137. 212.

03147000 Licking River at Toboso, Ohio

Years analyzed = 42

Climatic year range = 1904–60

[APEE, annual percentage equaled or exceeded; ft3/s, cubic foot per second; Sep, September; Nov, November]

Sep–Nov daily mean streamflow (ft3/s) that was equaled or exceeded the indicated percentage of time at APEE level

APEE 95 90 80 70 50 30 20 10 5

1 90.8 183. 286. 424. 1050. 2090. 2830. 4340. 5710.

2 81.5 175. 267. 350. 849. 1450. 2190. 3840. 4190.

5 74.5 124. 206. 256. 475. 836. 1050. 2200. 3220.

10 68.9 91.4 138. 171. 303. 490. 622. 1130. 1810.

20 65.8 73.8 116. 130. 201. 315. 383. 554. 699.

25 65.3 70.6 101. 123. 175. 285. 303. 471. 528.

30 63.2 68.9 96.5 116. 148. 237. 268. 414. 442.

40 61.2 66.0 83.4 98.9 118. 167. 215. 284. 353.

50 57.3 64.2 78.0 85.0 109. 134. 153. 214. 294.

60 54.8 60.2 74.7 84.6 97.3 111. 133. 190. 235.

70 51.8 59.0 71.5 80.4 92.5 100. 112. 141. 197.

75 50.6 55.6 69.2 73.9 88.0 98.2 104. 140. 188.

80 50.3 53.5 64.6 72.9 85.2 94.4 102. 136. 173.

90 48.1 50.5 61.0 69.4 77.3 90.9 98.1 116. 156.

95 46.1 49.0 60.2 68.0 74.0 86.4 94.8 112. 149.

98 44.3 48.3 58.9 64.9 72.8 84.4 92.7 111. 129.

99 44.3 46.6 57.2 64.0 72.0 84.1 92.4 108. 128.
112 Methods for Estimating Selected Low-Flow Statistics and Development of Annual Flow-Duration Statistics for Ohio

03149500 Salt Creek near Chandlersville, Ohio

Years analyzed = 20

Climatic year range = 1935–2008

[APEE, annual percentage equaled or exceeded; ft3/s, cubic foot per second; Sep, September; Nov, November]

Sep–Nov daily mean streamflow (ft3/s) that was equaled or exceeded the indicated percentage of time at APEE level

APEE 95 90 80 70 50 30 20 10 5

1 25.3 31.7 82.0 109. 285. 601. 864. 2000. 4000.

2 19.2 21.8 47.0 88.2 192. 306. 794. 1110. 3230.

5 7.18 9.40 31.0 50.5 86.0 152. 374. 511. 762.

10 6.15 7.13 11.8 26.1 40.9 86.1 169. 242. 290.

20 5.11 5.29 8.38 12.5 21.7 43.1 87.7 130. 152.

25 4.41 4.67 7.38 11.0 19.0 33.7 69.4 115. 134.

30 4.14 4.31 6.36 8.91 16.5 28.1 58.0 91.2 113.

40 3.13 3.49 5.49 6.74 12.5 23.2 46.2 62.6 68.9

50 2.71 2.82 3.44 5.83 9.05 17.4 31.6 48.4 50.0

60 1.51 1.79 3.04 4.39 5.74 13.8 24.0 37.7 42.4

70 0.72 1.00 2.26 3.00 3.54 7.74 16.5 29.0 34.0

75 0.49 0.81 2.10 2.52 3.10 7.33 14.6 22.9 30.6

80 0.35 0.80 1.02 2.16 2.60 6.71 10.5 18.4 27.0

90 0.04 0.13 0.42 1.14 1.86 4.22 5.72 16.0 22.9

95 0.03 0.11 0.29 0.81 1.49 3.74 4.42 12.5 19.7

98 0.03 0.10 0.24 0.74 1.30 3.34 3.99 10.3 16.4

99 0.01 0.10 0.24 0.73 1.30 3.21 3.96 9.04 14.7

03157000 Clear Creek near Rockbridge, Ohio

Years analyzed = 70

Climatic year range = 1939–2008

[APEE, annual percentage equaled or exceeded; ft3/s, cubic foot per second; Sep, September; Nov, November]

Sep–Nov daily mean streamflow (ft3/s) that was equaled or exceeded the indicated percentage of time at APEE level

APEE 98 95 90 80 50 20 10 5 2

1 20.4 22.1 32.2 70.6 165. 365. 771. 1150. 2020.

2 17.9 21.3 28.1 50.1 128. 282. 569. 960. 1140.

5 15.4 18.1 22.8 35.1 70.4 156. 376. 446. 625.

10 14.0 16.1 19.8 25.5 48.3 102. 160. 282. 332.

20 13.4 15.0 18.0 20.7 35.9 62.9 93.8 139. 191.

25 13.0 15.0 17.1 19.2 32.0 55.0 79.2 113. 157.

30 13.0 14.6 16.1 18.1 28.5 47.7 67.6 98.6 134.

40 12.4 13.6 15.1 18.0 23.1 34.8 53.3 69.8 108.

50 12.0 13.0 14.1 17.0 21.0 31.0 48.0 60.8 93.1

60 12.0 12.0 14.0 16.0 19.0 27.0 42.9 54.5 83.4

70 10.1 11.6 12.6 14.1 18.0 24.9 39.0 46.3 74.5

75 9.84 11.0 12.0 14.0 17.5 23.8 35.4 42.8 70.7

80 9.00 11.0 11.0 13.0 16.5 22.0 31.2 39.6 67.8

90 8.16 9.53 10.3 11.4 15.0 19.2 28.0 35.1 55.7

95 7.86 8.13 9.93 11.0 14.6 19.0 25.5 33.0 45.5

98 6.27 7.98 9.44 10.2 13.9 18.0 23.8 30.7 41.3

99 6.27 7.98 9.43 10.0 13.5 17.8 23.0 28.0 40.7
Appendix 4 113

03157500 Hocking River at Enterprise, Ohio

Years analyzed = 78

Climatic year range = 1931–2008

[APEE, annual percentage equaled or exceeded; ft3/s, cubic foot per second; Sep, September; Nov, November]

Sep–Nov daily mean streamflow (ft3/s) that was equaled or exceeded the indicated percentage of time at APEE level

APEE 98 95 90 80 50 20 10 5 2

1 70.3 93.3 145. 345. 929. 2200. 3780. 4620. 7650.

2 63.1 91.6 110. 240. 689. 1930. 3230. 3550. 5460.

5 55.0 74.1 83.6 154. 365. 933. 1650. 2200. 3500.

10 47.8 62.6 76.3 98.2 252. 538. 815. 1350. 1580.

20 44.2 53.4 62.0 72.9 148. 313. 449. 800. 891.

25 43.1 50.8 59.7 68.0 139. 247. 370. 706. 753.

30 40.3 49.8 57.8 66.2 127. 214. 338. 612. 654.

40 38.6 48.7 51.9 62.2 105. 161. 284. 465. 528.

50 36.5 41.9 46.9 56.0 88.0 134. 228. 300. 446.

60 35.5 39.0 44.8 54.0 77.8 129. 184. 262. 374.

70 32.3 36.5 39.9 51.8 70.5 118. 166. 225. 338.

75 30.2 33.9 38.7 45.8 68.0 107. 154. 206. 319.

80 29.0 32.4 37.7 44.9 66.0 99.3 151. 188. 292.

90 28.6 30.0 36.5 41.8 60.1 82.2 120. 158. 226.

95 28.0 29.0 33.7 39.6 55.5 76.8 114. 132. 202.

98 26.5 27.0 30.9 36.8 53.3 75.2 106. 117. 179.

99 26.2 27.0 30.9 36.8 52.0 75.0 101. 116. 175.

03159540 Shade River near Chester, Ohio

Years analyzed = 44

Climatic year range = 1965–2008

[APEE, annual percentage equaled or exceeded; ft3/s, cubic foot per second; Sep, September; Nov, November]

Sep–Nov daily mean streamflow (ft3/s) that was equaled or exceeded the indicated percentage of time at APEE level

APEE 95 90 80 70 50 30 20 10 5

1 31.3 64.0 205. 347. 479. 898. 1780. 2490. 2860.

2 26.2 61.1 138. 211. 411. 796. 1280. 2130. 2340.

5 16.3 35.5 59.4 79.4 204. 425. 556. 1060. 1670.

10 12.1 18.9 26.8 41.6 99.3 224. 295. 448. 771.

20 5.27 9.05 14.6 21.4 49.5 83.8 108. 228. 250.

25 4.45 7.80 12.0 15.0 37.5 67.0 84.0 189. 200.

30 3.26 6.62 9.04 12.7 28.2 51.9 66.8 163. 172.

40 1.43 4.45 6.06 8.24 18.1 29.8 44.4 108. 133.

50 0.98 2.50 4.10 5.15 10.2 22.5 37.0 82.5 108.

60 0.66 1.80 3.08 3.68 7.80 16.5 32.0 65.4 96.1

70 0.45 1.13 1.96 3.06 5.95 13.0 24.6 39.0 75.5

75 0.45 1.00 1.80 2.45 5.55 12.0 18.0 32.0 68.8

80 0.42 0.82 1.50 2.09 5.30 11.0 15.4 27.4 59.5

90 0.32 0.56 1.10 1.45 3.66 7.58 12.0 18.2 36.5

95 0.25 0.47 0.89 1.13 3.18 6.10 7.84 13.0 27.4

98 0.22 0.39 0.70 0.85 2.32 5.29 5.87 11.1 23.8

99 0.21 0.38 0.68 0.77 2.20 4.70 5.80 11.1 21.5
114 Methods for Estimating Selected Low-Flow Statistics and Development of Annual Flow-Duration Statistics for Ohio

03202000 Raccoon Creek at Adamsville, Ohio

Years analyzed = 86

Climatic year range = 1915–2008

[APEE, annual percentage equaled or exceeded; ft3/s, cubic foot per second; Sep, September; Nov, November]

Sep–Nov daily mean streamflow (ft3/s) that was equaled or exceeded the indicated percentage of time at APEE level

APEE 98 95 90 80 50 20 10 5 2

1 14.7 30.9 72.4 132. 721. 2060. 3850. 4880. 6750.

2 14.5 27.9 65.2 102. 647. 1970. 3760. 4750. 6660.

5 13.5 22.8 49.0 86.4 383. 1280. 2850. 3350. 5260.

10 11.7 15.1 34.4 63.5 216. 793. 1620. 2240. 2740.

20 7.55 11.2 25.8 40.4 113. 465. 703. 1020. 1330.

25 6.74 9.48 23.4 35.4 96.0 368. 577. 793. 928.

30 5.08 8.79 21.5 32.8 76.5 287. 497. 652. 817.

40 4.05 7.92 16.0 25.6 60.6 186. 365. 458. 591.

50 3.32 7.15 13.7 22.0 44.5 139. 238. 324. 523.

60 2.55 5.78 8.67 18.4 35.3 109. 176. 247. 439.

70 2.11 4.49 6.88 16.2 29.8 77.2 137. 189. 377.

75 1.97 4.00 6.51 12.4 28.0 73.0 125. 168. 349.

80 1.90 3.45 6.43 9.80 25.8 64.8 110. 152. 256.

90 1.72 2.67 5.64 7.59 21.2 51.4 79.1 99.5 214.

95 1.61 2.51 4.17 6.80 19.3 41.6 65.2 86.5 173.

98 1.38 2.19 3.77 6.44 17.3 38.9 56.9 82.2 156.

99 1.32 2.10 3.77 6.44 16.0 37.6 54.8 80.9 154.

03217500 Scioto River at La Rue, Ohio

Years analyzed = 22

Climatic year range = 1926–50

[APEE, annual percentage equaled or exceeded; ft3/s, cubic foot per second; Sep, September; Nov, November]

Sep–Nov daily mean streamflow (ft3/s) that was equaled or exceeded the indicated percentage of time at APEE level

APEE 95 90 80 70 50 30 20 10 5

1 13.0 22.3 48.4 78.9 282. 1130. 1290. 2610. 3550.

2 11.4 17.2 43.2 68.2 220. 830. 1060. 2080. 3160.

5 9.37 14.2 28.1 30.8 157. 341. 803. 1060. 1680.

10 7.64 10.7 19.0 21.8 60.4 249. 348. 558. 1200.

20 6.91 8.85 14.0 16.9 22.0 103. 183. 335. 587.

25 5.82 8.15 13.0 15.9 19.5 67.8 150. 222. 444.

30 5.78 7.34 12.0 12.9 18.5 56.8 118. 186. 341.

40 4.37 6.05 9.60 11.9 14.2 25.8 74.6 143. 251.

50 4.01 5.77 9.00 10.0 12.0 18.3 36.2 111. 186.

60 3.95 5.04 7.63 8.47 10.5 17.8 26.0 76.8 152.

70 3.82 3.93 5.95 7.90 8.90 16.0 22.2 44.8 121.

75 3.65 3.93 5.44 6.90 8.75 14.0 15.8 31.1 114.

80 3.09 3.69 5.21 6.00 8.50 12.6 14.8 28.9 102.

90 3.05 3.48 4.12 4.95 6.50 9.10 13.9 25.1 78.6

95 3.02 3.29 3.90 4.18 5.80 8.55 13.0 23.9 62.0

98 2.83 3.18 3.90 3.98 4.60 8.05 11.3 22.8 50.4

99 2.80 2.80 3.36 3.89 4.20 8.00 11.1 22.8 46.9
Appendix 4 115

03218000 Little Scioto River above Marion, Ohio

Years analyzed = 33

Climatic year range = 1938–70

[APEE, annual percentage equaled or exceeded; ft3/s, cubic foot per second; Sep, September; Nov, November]

Sep–Nov daily mean streamflow (ft3/s) that was equaled or exceeded the indicated percentage of time at APEE level

APEE 95 90 80 70 50 30 20 10 5

1 0.00 0.22 2.18 11.6 31.0 99.0 164. 347. 400.

2 0.00 0.15 1.99 11.6 27.0 72.5 144. 269. 333.

5 0.00 0.00 1.40 4.27 13.8 38.4 75.0 136. 160.

10 0.00 0.00 0.96 2.81 8.82 27.8 40.8 75.0 91.6

20 0.00 0.00 0.76 1.26 3.14 10.0 20.2 32.8 46.6

25 0.00 0.00 0.58 0.84 2.00 7.10 15.0 24.6 36.2

30 0.00 0.00 0.40 0.63 1.70 5.35 10.9 18.0 24.9

40 0.00 0.00 0.26 0.40 1.10 3.03 6.86 12.4 16.5

50 0.00 0.00 0.18 0.30 0.90 1.76 5.10 8.88 11.3

60 0.00 0.00 0.08 0.20 0.60 1.32 3.07 5.44 7.26

70 0.00 0.00 0.00 0.02 0.40 0.85 1.27 4.27 5.36

75 0.00 0.00 0.00 0.00 0.40 0.66 0.91 3.88 4.64

80 0.00 0.00 0.00 0.00 0.30 0.58 0.73 3.57 4.32

90 0.00 0.00 0.00 0.00 0.20 0.41 0.62 1.90 3.66

95 0.00 0.00 0.00 0.00 0.10 0.35 0.53 1.39 3.00

98 0.00 0.00 0.00 0.00 0.00 0.30 0.46 1.24 2.77

99 0.00 0.00 0.00 0.00 0.00 0.28 0.45 1.12 1.93

03219500 Scioto River near Prospect, Ohio

Years analyzed = 77

Climatic year range = 1925–2008

[APEE, annual percentage equaled or exceeded; ft3/s, cubic foot per second; Sep, September; Nov, November]

Sep–Nov daily mean streamflow (ft3/s) that was equaled or exceeded the indicated percentage of time at APEE level

APEE 98 95 90 80 50 20 10 5 2

1 26.8 39.0 45.8 65.2 483. 2300. 3950. 4970. 5870.

2 24.8 33.5 43.1 59.0 395. 2110. 3600. 4550. 5410.

5 20.9 27.4 34.2 43.5 229. 1380. 2370. 3600. 4260.

10 19.1 22.2 25.8 36.0 152. 815. 1650. 2300. 3080.

20 16.6 17.9 19.9 28.0 79.8 344. 657. 1210. 1970.

25 15.6 16.9 19.6 25.6 57.0 257. 484. 877. 1530.

30 15.0 16.8 17.3 24.2 47.4 219. 346. 630. 1090.

40 13.6 14.9 16.2 21.0 36.2 129. 245. 407. 724.

50 12.1 13.9 15.0 18.6 29.0 85.6 210. 290. 449.

60 11.0 12.7 13.8 16.5 25.0 70.1 137. 228. 350.

70 9.78 11.0 12.0 14.0 23.0 52.0 110. 177. 270.

75 9.62 11.0 11.8 13.0 21.0 45.8 91.4 166. 234.

80 8.37 10.9 11.0 13.0 20.4 41.4 77.6 114. 207.

90 7.53 9.21 10.0 12.0 18.0 32.3 46.6 81.2 163.

95 7.03 8.33 8.96 11.0 17.0 26.2 43.7 58.2 117.

98 5.80 7.03 8.24 10.9 15.8 21.3 40.4 46.7 81.5

99 5.06 6.74 7.58 9.38 15.0 21.0 32.6 46.5 73.6
116 Methods for Estimating Selected Low-Flow Statistics and Development of Annual Flow-Duration Statistics for Ohio

03220000 Mill Creek near Bellepoint, Ohio

Years analyzed = 66

Climatic year range = 1943–2008

[APEE, annual percentage equaled or exceeded; ft3/s, cubic foot per second; Sep, September; Nov, November]

Sep–Nov daily mean streamflow (ft3/s) that was equaled or exceeded the indicated percentage of time at APEE level

APEE 98 95 90 80 50 20 10 5 2

1 6.27 10.1 14.4 33.4 303. 1510. 2390. 3340. 3900.

2 5.49 8.06 12.0 26.0 203. 1370. 2100. 2800. 3250.

5 3.79 5.19 8.73 15.5 113. 645. 1240. 1630. 1970.

10 2.65 4.27 6.55 10.9 51.5 203. 405. 720. 1140.

20 2.04 3.36 5.64 8.11 22.9 78.6 138. 232. 260.

25 1.97 3.04 5.55 7.70 20.0 62.6 110. 168. 230.

30 1.93 2.44 5.09 6.39 15.5 43.0 87.3 121. 169.

40 1.70 1.96 3.67 5.38 11.0 25.8 45.6 75.2 101.

50 1.37 1.64 2.31 4.78 8.45 18.2 32.9 55.2 69.2

60 1.02 1.30 1.58 4.18 7.40 15.6 26.5 47.7 51.3

70 0.85 1.02 1.30 3.42 6.41 12.6 21.6 37.8 41.9

75 0.80 0.90 1.20 2.92 5.95 10.5 18.3 30.6 34.3

80 0.67 0.81 1.06 1.96 5.74 9.68 14.9 25.2 30.1

90 0.31 0.60 0.70 1.47 4.38 7.52 11.1 15.9 22.8

95 0.12 0.50 0.70 1.06 3.60 6.83 7.93 13.5 17.7

98 0.03 0.37 0.64 0.80 2.98 5.87 6.80 10.3 15.4

99 0.03 0.24 0.40 0.80 2.80 5.46 6.46 9.65 14.7

03223000 Olentangy River at Claridon, Ohio

Years analyzed = 52

Climatic year range = 1946–97

[APEE, annual percentage equaled or exceeded; ft3/s, cubic foot per second; Sep, September; Nov, November]

Sep–Nov daily mean streamflow (ft3/s) that was equaled or exceeded the indicated percentage of time at APEE level

APEE 98 95 90 80 50 20 10 5 2

1 8.14 11.5 24.2 41.2 229. 1160. 1450. 1850. 2580.

2 5.12 9.11 22.4 30.9 205. 968. 1380. 1630. 2350.

5 3.54 6.54 13.6 17.7 111. 421. 906. 1190. 1320.

10 2.70 4.66 8.65 11.9 58.1 238. 361. 764. 928.

20 2.20 3.23 6.01 8.09 27.8 127. 189. 298. 405.

25 1.71 2.68 5.51 7.46 22.5 90.8 156. 212. 306.

30 1.41 2.23 4.94 6.46 19.2 70.2 117. 169. 260.

40 0.86 1.69 3.32 5.15 13.6 31.5 69.4 109. 197.

50 0.73 1.40 2.86 4.36 9.70 20.0 48.6 93.0 125.

60 0.44 1.06 2.00 3.40 6.80 16.0 32.9 74.0 104.

70 0.14 0.86 1.33 2.51 6.16 12.0 27.4 58.3 95.7

75 0.03 0.57 0.96 1.83 5.60 11.0 24.6 51.1 73.8

80 0.01 0.46 0.86 1.34 5.09 9.94 17.7 39.8 42.7

90 0.00 0.15 0.43 0.88 3.66 8.41 11.8 24.9 32.1

95 0.00 0.06 0.30 0.72 3.11 6.94 10.4 19.1 26.6

98 0.00 0.03 0.23 0.54 2.70 6.39 9.27 17.4 21.6

99 0.00 0.02 0.23 0.53 2.70 6.32 9.07 17.4 20.0
Appendix 4 117

03228300 Big Walnut Creek at Sunbury, Ohio

Years analyzed = 21

Climatic year range = 1988–2008

[APEE, annual percentage equaled or exceeded; ft3/s, cubic foot per second; Sep, September; Nov, November]

Sep–Nov daily mean streamflow (ft3/s) that was equaled or exceeded the indicated percentage of time at APEE level

APEE 95 90 80 70 50 30 20 10 5

1 1.25 12.0 28.2 175. 407. 691. 896. 1540. 3050.

2 0.93 8.24 23.7 106. 258. 510. 742. 1240. 1920.

5 0.53 3.62 11.3 26.9 124. 239. 353. 712. 943.

10 0.21 1.90 6.22 13.8 68.2 110. 162. 272. 318.

20 0.08 0.84 3.79 5.98 16.0 56.5 71.7 106. 121.

25 0.04 0.52 2.96 4.28 9.40 46.0 50.6 76.6 88.7

30 0.04 0.44 1.20 3.02 7.20 35.0 43.6 51.7 70.0

40 0.01 0.15 0.66 2.27 3.80 24.4 32.2 34.8 48.9

50 0.00 0.06 0.34 0.72 2.60 12.4 19.6 29.4 39.0

60 0.00 0.02 0.14 0.26 1.08 6.63 12.1 21.6 32.0

70 0.00 0.01 0.05 0.09 0.67 5.14 8.15 11.2 25.5

75 0.00 0.00 0.02 0.07 0.40 3.04 6.36 8.98 22.5

80 0.00 0.00 0.01 0.06 0.30 2.38 4.69 7.14 20.0

90 0.00 0.00 0.00 0.01 0.16 0.86 2.19 4.10 16.6

95 0.00 0.00 0.00 0.01 0.05 0.38 1.80 2.52 7.55

98 0.00 0.00 0.00 0.00 0.04 0.24 0.92 1.46 6.68

99 0.00 0.00 0.00 0.00 0.04 0.22 0.67 1.14 5.97

03230500 Big Darby Creek at Darbyville, Ohio

Years analyzed = 85

Climatic year range = 1921–2008

[APEE, annual percentage equaled or exceeded; ft3/s, cubic foot per second; Sep, September; Nov, November]

Sep–Nov daily mean streamflow (ft3/s) that was equaled or exceeded the indicated percentage of time at APEE level

APEE 98 95 90 80 50 20 10 5 2

1 22.6 26.2 46.2 96.0 527. 2400. 5030. 5540. 7530.

2 21.8 25.4 41.4 81.8 466. 1980. 4460. 4750. 6860.

5 19.9 24.5 36.2 64.5 278. 1210. 2990. 3650. 3900.

10 16.2 22.0 34.5 51.6 160. 547. 1560. 1950. 2690.

20 14.8 18.0 29.4 40.4 85.6 264. 669. 941. 1100.

25 12.7 17.3 28.6 37.2 68.0 222. 429. 705. 861.

30 10.7 15.3 25.9 33.7 63.0 170. 361. 607. 711.

40 8.83 12.4 21.7 28.2 47.4 133. 266. 393. 490.

50 7.88 11.0 18.0 24.0 41.0 98.8 159. 294. 398.

60 6.19 8.98 15.8 19.4 35.8 85.7 125. 257. 341.

70 5.24 8.27 12.0 18.4 32.6 69.4 102. 214. 279.

75 4.52 7.56 11.2 16.2 31.0 63.6 91.4 182. 248.

80 4.19 6.39 9.78 15.5 29.0 50.1 81.5 168. 228.

90 3.49 4.61 7.52 13.0 25.0 44.1 69.8 132. 194.

95 2.58 3.72 6.48 12.0 23.0 40.9 60.8 95.6 155.

98 1.85 3.48 6.00 11.6 21.0 40.0 56.3 73.9 129.

99 1.76 3.42 5.80 10.2 21.0 39.0 56.0 69.4 123.
118 Methods for Estimating Selected Low-Flow Statistics and Development of Annual Flow-Duration Statistics for Ohio

03232000 Paint Creek near Greenfield, Ohio

Years analyzed = 55

Climatic year range = 1926–2008

[APEE, annual percentage equaled or exceeded; ft3/s, cubic foot per second; Sep, September; Nov, November]

Sep–Nov daily mean streamflow (ft3/s) that was equaled or exceeded the indicated percentage of time at APEE level

APEE 98 95 90 80 50 20 10 5 2

1 5.11 6.88 15.4 60.6 360. 1160. 1980. 4610. 5180.

2 3.66 4.88 14.3 41.8 248. 863. 1880. 3730. 4640.

5 2.43 4.52 8.30 18.7 132. 571. 1300. 1800. 2570.

10 1.46 3.39 5.88 13.0 77.8 335. 665. 1230. 1900.

20 1.10 2.60 4.28 8.40 35.6 144. 299. 567. 821.

25 0.97 2.32 3.54 6.46 29.0 129. 259. 448. 558.

30 0.95 2.09 3.08 5.41 24.2 119. 233. 393. 476.

40 0.69 1.46 2.61 4.50 18.0 85.4 172. 302. 320.

50 0.51 1.00 1.82 3.84 14.0 56.0 95.0 235. 240.

60 0.32 0.50 1.37 2.92 11.8 43.4 73.9 183. 201.

70 0.21 0.37 1.08 2.40 8.30 34.6 58.0 143. 165.

75 0.20 0.29 0.96 1.96 7.00 28.4 53.8 132. 149.

80 0.15 0.28 0.78 1.40 5.62 18.8 47.6 122. 148.

90 0.11 0.19 0.46 1.02 3.46 14.8 32.7 70.0 114.

95 0.02 0.15 0.36 0.62 2.60 9.10 28.5 55.8 99.3

98 0.01 0.10 0.25 0.45 2.20 7.25 25.8 45.2 96.0

99 0.01 0.10 0.21 0.40 2.20 7.12 24.8 44.4 95.9

03235500 Tar Hollow Creek at Tar Hollow State Park, Ohio

Years analyzed = 32

Climatic year range = 1946–77

[APEE, annual percentage equaled or exceeded; ft3/s, cubic foot per second; Sep, September; Nov, November]

Sep–Nov daily mean streamflow (ft3/s) that was equaled or exceeded the indicated percentage of time at APEE level

APEE 95 90 80 70 50 30 20 10 5

1 0.00 0.00 0.00 0.27 1.65 4.13 6.96 11.7 14.0

2 0.00 0.00 0.00 0.27 1.24 3.92 4.79 5.90 8.43

5 0.00 0.00 0.00 0.00 0.42 1.07 1.41 2.62 5.01

10 0.00 0.00 0.00 0.00 0.24 0.44 0.59 0.98 3.16

20 0.00 0.00 0.00 0.00 0.05 0.21 0.34 0.49 1.91

25 0.00 0.00 0.00 0.00 0.01 0.20 0.33 0.40 1.64

30 0.00 0.00 0.00 0.00 0.00 0.12 0.24 0.40 1.27

40 0.00 0.00 0.00 0.00 0.00 0.06 0.14 0.27 0.64

50 0.00 0.00 0.00 0.00 0.00 0.03 0.11 0.20 0.35

60 0.00 0.00 0.00 0.00 0.00 0.01 0.08 0.10 0.21

70 0.00 0.00 0.00 0.00 0.00 0.00 0.04 0.10 0.13

75 0.00 0.00 0.00 0.00 0.00 0.00 0.02 0.09 0.11

80 0.00 0.00 0.00 0.00 0.00 0.00 0.02 0.04 0.11

90 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.03 0.07

95 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.03 0.05

98 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.02 0.04

99 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.01 0.04
Appendix 4 119

03237280 Upper Twin Creek at McGaw, Ohio

Years analyzed = 46

Climatic year range = 1963–2008

[APEE, annual percentage equaled or exceeded; ft3/s, cubic foot per second; Sep, September; Nov, November]

Sep–Nov daily mean streamflow (ft3/s) that was equaled or exceeded the indicated percentage of time at APEE level

APEE 95 90 80 70 50 30 20 10 5

1 0.61 0.90 3.78 9.91 36.0 103. 184. 297. 374.

2 0.53 0.84 3.53 5.00 18.9 83.6 98.8 189. 246.

5 0.23 0.56 1.51 3.11 8.47 27.3 43.3 73.4 80.7

10 0.12 0.21 0.73 1.37 5.41 13.1 19.4 31.2 37.3

20 0.04 0.11 0.27 0.64 2.89 4.70 7.40 17.2 24.2

25 0.01 0.09 0.21 0.48 1.80 3.76 6.00 13.6 20.6

30 0.00 0.08 0.16 0.41 1.16 3.07 4.06 12.5 15.4

40 0.00 0.00 0.08 0.21 0.77 1.85 2.28 5.97 9.34

50 0.00 0.00 0.04 0.13 0.43 0.78 1.62 2.65 7.21

60 0.00 0.00 0.02 0.09 0.24 0.58 1.15 2.04 5.77

70 0.00 0.00 0.01 0.05 0.13 0.34 0.79 1.78 4.18

75 0.00 0.00 0.00 0.03 0.11 0.29 0.63 1.60 3.26

80 0.00 0.00 0.00 0.02 0.07 0.27 0.51 1.41 2.62

90 0.00 0.00 0.00 0.00 0.03 0.18 0.30 0.69 1.10

95 0.00 0.00 0.00 0.00 0.02 0.14 0.22 0.51 0.85

98 0.00 0.00 0.00 0.00 0.02 0.10 0.19 0.43 0.65

99 0.00 0.00 0.00 0.00 0.02 0.10 0.18 0.42 0.64

03237500 Ohio Brush Creek near West Union, Ohio

Years analyzed = 78

Climatic year range = 1926–2008

[APEE, annual percentage equaled or exceeded; ft3/s, cubic foot per second; Sep, September; Nov, November]

Sep–Nov daily mean streamflow (ft3/s) that was equaled or exceeded the indicated percentage of time at APEE level

APEE 98 95 90 80 50 20 10 5 2

1 3.49 11.8 63.8 330. 1920. 4900. 8080. 8890. 13400.

2 3.22 8.72 49.7 191. 1330. 3360. 4990. 8150. 10200.

5 2.27 4.90 22.7 82.9 483. 1480. 2080. 2950. 5500.

10 2.05 4.35 14.1 33.2 210. 668. 947. 1330. 2210.

20 1.27 2.98 7.35 16.9 85.1 244. 429. 555. 906.

25 1.00 2.65 6.64 15.2 61.5 178. 307. 435. 700.

30 0.93 2.35 4.16 10.3 48.5 151. 256. 343. 579.

40 0.82 1.97 2.89 6.88 30.7 104. 172. 223. 353.

50 0.32 1.10 1.68 4.60 15.5 58.4 123. 154. 263.

60 0.22 0.90 1.20 3.47 11.2 44.4 82.7 124. 203.

70 0.19 0.67 0.95 1.97 7.44 29.4 63.5 95.3 161.

75 0.14 0.54 0.80 1.58 6.05 25.6 57.9 81.5 141.

80 0.13 0.48 0.68 1.34 5.28 22.8 49.5 76.1 123.

90 0.06 0.20 0.32 0.87 3.94 18.2 34.1 64.1 84.0

95 0.06 0.13 0.20 0.83 3.27 13.5 27.1 51.1 66.8

98 0.06 0.11 0.20 0.74 2.59 10.8 21.6 49.2 57.5

99 0.06 0.11 0.20 0.57 2.55 10.0 18.4 49.1 56.4
120 Methods for Estimating Selected Low-Flow Statistics and Development of Annual Flow-Duration Statistics for Ohio

03238500 White Oak Creek near Georgetown, Ohio

Years analyzed = 81

Climatic year range = 1924–2008

[APEE, annual percentage equaled or exceeded; ft3/s, cubic foot per second; Sep, September; Nov, November]

Sep–Nov daily mean streamflow (ft3/s) that was equaled or exceeded the indicated percentage of time at APEE level

APEE 98 95 90 80 50 20 10 5 2

1 5.76 9.03 22.4 116. 970. 4510. 5920. 7190. 9130.

2 5.60 7.31 18.7 104. 705. 2910. 4210. 5580. 6610.

5 2.54 4.14 11.2 30.7 218. 1150. 1890. 3000. 3800.

10 0.72 2.54 6.26 14.4 91.2 451. 637. 938. 1400.

20 0.10 0.79 3.28 8.88 34.2 148. 196. 303. 383.

25 0.06 0.51 2.80 8.12 27.0 99.2 144. 203. 282.

30 0.06 0.40 2.24 6.66 22.0 77.2 111. 164. 200.

40 0.00 0.21 1.51 5.18 13.2 46.8 72.4 106. 124.

50 0.00 0.11 0.42 3.58 9.00 32.6 53.2 75.4 92.8

60 0.00 0.00 0.20 1.96 4.80 22.7 34.1 46.3 74.5

70 0.00 0.00 0.10 0.78 3.72 16.0 25.2 35.5 46.9

75 0.00 0.00 0.10 0.72 3.00 12.6 22.4 29.6 42.1

80 0.00 0.00 0.00 0.40 1.90 11.0 19.3 23.0 36.8

90 0.00 0.00 0.00 0.10 0.92 7.22 11.8 18.3 27.9

95 0.00 0.00 0.00 0.00 0.62 4.97 9.10 15.0 20.6

98 0.00 0.00 0.00 0.00 0.40 3.76 7.62 13.9 17.7

99 0.00 0.00 0.00 0.00 0.40 3.12 7.38 13.7 16.7

03240000 Little Miami River near Oldtown, Ohio

Years analyzed = 57

Climatic year range = 1952–2008

[APEE, annual percentage equaled or exceeded; ft3/s, cubic foot per second; Sep, September; Nov, November]

Sep–Nov daily mean streamflow (ft3/s) that was equaled or exceeded the indicated percentage of time at APEE level

APEE 98 95 90 80 50 20 10 5 2

1 13.5 19.6 23.0 34.0 209. 570. 939. 1660. 2910.

2 13.3 16.5 22.0 32.0 164. 458. 756. 1490. 2360.

5 12.7 14.9 20.8 25.0 99.8 220. 519. 587. 715.

10 12.2 13.9 19.0 23.9 60.8 133. 237. 371. 385.

20 11.3 13.0 17.6 20.6 42.0 75.5 131. 200. 232.

25 11.2 12.0 16.6 20.0 34.0 68.8 112. 168. 209.

30 11.2 12.0 15.6 18.6 31.0 64.6 99.5 151. 187.

40 10.2 11.9 14.6 17.1 29.0 53.5 74.4 127. 165.

50 9.28 10.9 13.0 16.6 26.0 48.8 64.6 118. 146.

60 8.61 10.8 12.6 14.6 23.0 41.9 58.0 97.1 129.

70 8.18 9.81 11.0 13.0 21.0 37.8 53.6 74.1 119.

75 7.88 9.61 10.8 13.0 20.0 36.4 51.4 69.3 115.

80 7.01 8.80 9.56 12.0 19.0 36.0 49.4 64.6 109.

90 6.06 7.85 8.58 11.7 18.0 32.0 42.0 48.5 101.

95 5.77 7.29 7.98 10.8 16.6 27.8 38.2 47.8 96.3

98 5.34 6.76 7.43 9.80 15.8 26.5 36.2 46.2 93.4

99 3.76 5.28 7.18 9.42 15.0 26.0 36.0 45.1 91.5
Appendix 4 121

03241500 Massies Creek at Wilberforce, Ohio

Years analyzed = 57

Climatic year range = 1952–2008

[APEE, annual percentage equaled or exceeded; ft3/s, cubic foot per second; Sep, September; Nov, November]

Sep–Nov daily mean streamflow (ft3/s) that was equaled or exceeded the indicated percentage of time at APEE level

APEE 98 95 90 80 50 20 10 5 2

1 3.32 5.90 10.8 17.0 123. 378. 608. 998. 1350.

2 3.11 5.67 8.43 14.3 99.6 325. 531. 781. 1230.

5 2.74 5.02 6.78 10.3 59.8 142. 336. 445. 570.

10 2.27 4.37 5.75 8.26 34.6 91.6 144. 225. 312.

20 2.11 4.06 5.06 7.02 21.0 46.5 82.3 118. 151.

25 2.11 3.74 4.88 6.46 16.0 35.8 58.8 102. 124.

30 1.99 3.31 4.67 6.22 13.4 30.2 51.6 93.4 94.1

40 1.99 3.09 4.10 5.52 11.0 21.0 41.3 66.2 84.6

50 1.62 2.89 3.76 5.12 9.70 19.0 34.4 54.7 65.2

60 1.49 2.59 3.20 4.22 8.78 16.4 27.0 46.5 57.2

70 1.12 1.71 2.46 3.84 7.00 14.8 21.4 38.8 49.0

75 0.68 1.55 2.26 3.60 6.00 13.0 20.2 36.2 45.6

80 0.60 1.37 1.90 3.18 6.00 10.4 16.5 32.9 43.2

90 0.50 1.18 1.76 2.66 5.30 7.97 14.2 22.3 36.8

95 0.41 1.05 1.50 2.36 4.02 7.22 12.6 19.2 34.1

98 0.40 0.98 1.48 2.25 3.78 6.82 9.60 15.3 31.1

99 0.39 0.90 1.48 2.12 3.70 6.50 8.82 15.2 29.6

03260700 Bokengehalas Creek near De Graff, Ohio

Years analyzed = 34

Climatic year range = 1957–90

[APEE, annual percentage equaled or exceeded; ft3/s, cubic foot per second; Sep, September; Nov, November]

Sep–Nov daily mean streamflow (ft3/s) that was equaled or exceeded the indicated percentage of time at APEE level

APEE 95 90 80 70 50 30 20 10 5

1 11.8 13.0 19.0 29.5 52.5 103. 149. 309. 375.

2 8.96 10.8 15.6 24.4 42.5 76.8 85.9 226. 333.

5 6.81 8.42 12.0 16.5 26.4 45.3 56.8 116. 186.

10 5.80 7.20 8.88 13.0 19.9 29.8 38.2 51.1 116.

20 5.68 6.47 7.80 9.84 14.3 19.0 22.0 34.5 68.8

25 5.27 6.35 7.50 9.20 13.0 16.5 21.0 30.0 59.5

30 5.27 6.13 7.30 8.84 11.6 15.5 20.0 24.6 53.5

40 4.88 5.24 6.50 7.51 9.82 14.0 17.0 20.5 41.1

50 4.50 5.10 6.20 6.95 8.85 12.5 15.0 19.0 31.3

60 4.43 4.90 5.80 6.48 8.39 10.5 14.0 17.0 26.8

70 4.10 4.60 5.60 6.10 7.88 10.5 12.6 16.0 24.6

75 4.10 4.50 5.50 5.80 7.80 9.95 12.0 15.0 23.0

80 3.95 4.45 5.30 5.65 7.47 9.86 12.0 13.0 15.8

90 3.49 4.20 4.92 5.30 6.86 9.10 10.0 12.0 13.8

95 3.47 3.94 4.76 5.07 6.48 8.65 9.80 11.5 13.0

98 3.25 3.85 4.27 4.93 6.37 8.14 9.07 10.9 12.8

99 3.25 3.85 4.10 4.85 6.15 8.10 9.00 10.4 12.0
122 Methods for Estimating Selected Low-Flow Statistics and Development of Annual Flow-Duration Statistics for Ohio

03264000 Greenville Creek near Bradford, Ohio

Years analyzed = 77

Climatic year range = 1930–2008

[APEE, annual percentage equaled or exceeded; ft3/s, cubic foot per second; Sep, September; Nov, November]

Sep–Nov daily mean streamflow (ft3/s) that was equaled or exceeded the indicated percentage of time at APEE level

APEE 98 95 90 80 50 20 10 5 2

1 23.4 26.9 38.8 65.6 230. 1140. 1890. 2830. 4130.

2 22.5 25.9 35.3 59.8 198. 969. 1780. 2430. 3760.

5 19.5 22.9 30.8 44.8 123. 476. 861. 1220. 2100.

10 17.1 21.5 26.0 36.5 72.4 261. 434. 527. 820.

20 15.6 19.7 25.2 30.6 52.6 134. 206. 237. 385.

25 15.0 18.7 23.8 29.0 45.0 94.8 169. 194. 326.

30 14.6 18.6 23.6 27.8 42.0 79.0 138. 160. 267.

40 14.0 16.9 21.8 25.0 37.0 60.6 98.8 124. 194.

50 12.1 14.9 18.8 23.2 34.0 52.4 84.4 108. 150.

60 12.1 13.9 15.6 21.0 29.0 47.7 63.7 89.0 134.

70 10.9 12.0 13.5 19.0 27.0 41.0 54.0 79.0 121.

75 10.5 11.0 12.8 18.0 26.0 38.2 51.4 76.5 116.

80 9.46 10.9 12.0 15.8 24.0 35.4 47.8 73.7 111.

90 8.37 9.00 11.0 14.6 22.0 31.5 41.0 65.3 102.

95 7.73 8.29 9.97 13.0 21.2 29.6 36.8 62.5 94.6

98 6.49 7.40 9.07 12.1 20.0 28.0 34.7 61.5 86.7

99 6.20 7.38 8.20 10.6 19.0 27.4 33.0 60.5 82.5

03265000 Stillwater River at Pleasant Hill, Ohio

Years analyzed = 87

Climatic year range = 1916–2008

[APEE, annual percentage equaled or exceeded; ft3/s, cubic foot per second; Sep, September; Nov, November]

Sep–Nov daily mean streamflow (ft3/s) that was equaled or exceeded the indicated percentage of time at APEE level

APEE 98 95 90 80 50 20 10 5 2

1 27.6 41.4 68.8 116. 608. 4040. 6740. 8320. 11200.

2 26.9 37.4 67.2 107. 375. 3100. 5860. 6440. 8740.

5 23.6 32.4 56.8 78.6 215. 1350. 3170. 4150. 5200.

10 22.5 30.2 45.0 64.5 133. 719. 1250. 1870. 2660.

20 22.0 27.6 37.6 50.6 106. 338. 526. 932. 1350.

25 22.0 26.2 35.8 47.6 84.0 265. 448. 755. 1230.

30 21.8 25.4 34.3 44.8 78.2 206. 311. 566. 1010.

40 20.8 24.2 30.5 40.0 62.0 139. 232. 414. 659.

50 15.0 21.0 26.8 36.0 55.0 105. 203. 291. 418.

60 13.6 19.0 23.4 31.5 49.0 91.9 159. 203. 317.

70 12.5 17.0 19.9 26.0 43.0 73.6 117. 186. 264.

75 11.8 16.0 18.6 24.0 40.0 68.0 110. 175. 236.

80 11.0 14.0 16.3 22.6 38.0 64.8 97.2 166. 214.

90 8.91 10.1 13.8 16.2 33.0 52.7 64.6 145. 167.

95 7.93 9.87 11.5 14.0 28.6 48.0 60.9 128. 153.

98 7.13 8.50 9.54 12.8 25.7 41.9 55.2 116. 141.

99 5.52 7.88 9.00 12.0 24.0 41.0 55.0 112. 137.
Appendix 4 123

03266500 Mad River at Zanesfield, Ohio

Years analyzed = 34

Climatic year range = 1946–79

[APEE, annual percentage equaled or exceeded; ft3/s, cubic foot per second; Sep, September; Nov, November]

Sep–Nov daily mean streamflow (ft3/s) that was equaled or exceeded the indicated percentage of time at APEE level

APEE 95 90 80 70 50 30 20 10 5

1 1.68 2.25 3.20 4.80 10.4 22.5 32.0 79.5 114.

2 1.36 1.79 2.80 4.19 7.59 13.9 22.8 41.3 67.0

5 1.28 1.52 1.94 2.80 5.19 8.35 11.2 16.2 30.0

10 1.17 1.40 1.80 2.15 3.67 4.62 7.08 9.36 17.6

20 1.08 1.23 1.56 1.85 2.71 3.25 4.10 5.54 9.52

25 0.97 1.20 1.50 1.80 2.40 3.10 3.70 5.00 8.13

30 0.97 1.20 1.50 1.62 2.20 2.85 3.14 4.55 7.07

40 0.95 1.16 1.50 1.50 2.00 2.35 2.60 3.92 6.01

50 0.95 1.10 1.30 1.40 1.75 2.20 2.30 3.60 4.85

60 0.93 1.00 1.10 1.40 1.55 2.05 2.20 3.40 4.49

70 0.90 1.00 1.10 1.30 1.45 1.95 2.16 2.95 4.14

75 0.80 0.95 1.00 1.20 1.40 1.90 2.10 2.80 4.00

80 0.80 0.84 1.00 1.20 1.35 1.90 2.10 2.74 3.32

90 0.77 0.80 0.99 1.05 1.30 1.80 1.90 2.10 3.03

95 0.70 0.78 0.90 0.98 1.20 1.65 1.80 2.05 2.95

98 0.68 0.77 0.90 0.93 1.18 1.55 1.80 1.94 2.85

99 0.68 0.77 0.90 0.93 1.10 1.55 1.80 1.90 2.85

03267000 Mad River near Urbana, Ohio

Years analyzed = 72

Climatic year range = 1925–2008

[APEE, annual percentage equaled or exceeded; ft3/s, cubic foot per second; Sep, September; Nov, November]

Sep–Nov daily mean streamflow (ft3/s) that was equaled or exceeded the indicated percentage of time at APEE level

APEE 98 95 90 80 50 20 10 5 2

1 39.4 52.0 71.6 92.4 177. 639. 950. 1070. 1490.

2 39.0 50.9 66.1 79.1 153. 409. 670. 844. 1160.

5 38.1 49.4 60.6 70.6 121. 231. 401. 562. 780.

10 37.9 48.2 55.7 66.1 103. 166. 255. 349. 514.

20 37.0 46.0 50.3 58.6 90.0 144. 163. 258. 342.

25 36.0 45.0 48.0 57.0 85.0 133. 159. 229. 285.

30 36.0 43.6 47.3 55.6 80.5 122. 152. 221. 256.

40 35.1 42.7 46.0 53.2 78.0 117. 138. 186. 229.

50 35.1 41.0 45.0 51.6 75.5 111. 131. 166. 215.

60 33.6 40.0 43.0 50.6 73.0 107. 122. 157. 203.

70 32.2 38.7 42.1 48.6 71.5 101. 118. 147. 179.

75 32.2 38.3 39.3 47.6 70.0 100. 115. 134. 173.

80 31.9 36.4 38.3 47.6 68.4 97.6 114. 129. 163.

90 31.8 35.0 38.3 45.2 65.1 96.0 101. 117. 148.

95 30.3 34.7 37.0 43.6 63.8 93.2 99.1 114. 146.

98 29.8 34.0 35.6 42.8 62.9 92.3 98.6 111. 143.

99 29.8 34.0 35.3 41.6 62.5 91.8 98.1 111. 142.
124 Methods for Estimating Selected Low-Flow Statistics and Development of Annual Flow-Duration Statistics for Ohio

03270800 Wolf Creek at Trotwood, Ohio

Years analyzed = 24

Climatic year range = 1962–85

[APEE, annual percentage equaled or exceeded; ft3/s, cubic foot per second; Sep, September; Nov, November]

Sep–Nov daily mean streamflow (ft3/s) that was equaled or exceeded the indicated percentage of time at APEE level

APEE 95 90 80 70 50 30 20 10 5

1 0.85 3.40 14.0 24.5 63.0 126. 259. 517. 597.

2 0.75 3.06 11.5 15.8 44.1 96.9 204. 368. 421.

5 0.67 2.32 6.00 7.54 15.2 42.5 95.8 151. 268.

10 0.53 1.39 4.00 4.62 8.66 20.6 31.0 66.6 94.2

20 0.42 1.13 2.20 3.18 5.54 12.3 14.0 25.4 30.5

25 0.40 0.85 1.70 2.50 3.95 8.35 11.0 18.0 26.3

30 0.40 0.80 1.60 2.20 3.42 6.08 9.30 13.5 20.1

40 0.40 0.67 1.40 1.72 2.66 4.22 6.16 9.05 13.2

50 0.25 0.58 1.20 1.40 2.00 3.10 3.90 5.45 9.65

60 0.25 0.48 0.86 1.05 1.53 2.43 3.10 4.23 9.39

70 0.16 0.36 0.43 0.69 1.08 1.45 2.16 3.65 8.43

75 0.13 0.25 0.36 0.54 1.00 1.30 1.90 3.30 7.80

80 0.13 0.23 0.34 0.54 0.86 1.20 1.90 2.61 7.10

90 0.01 0.09 0.28 0.34 0.64 0.89 1.14 1.80 5.54

95 0.01 0.06 0.24 0.30 0.53 0.81 0.90 1.74 4.58

98 0.00 0.02 0.18 0.29 0.45 0.64 0.78 1.55 3.89

99 0.00 0.02 0.17 0.29 0.40 0.57 0.78 1.55 3.58

03271000 Wolf Creek at Dayton, Ohio

Years analyzed = 29

Climatic year range = 1938–2008

[APEE, annual percentage equaled or exceeded; ft3/s, cubic foot per second; Sep, September; Nov, November]

Sep–Nov daily mean streamflow (ft3/s) that was equaled or exceeded the indicated percentage of time at APEE level

APEE 95 90 80 70 50 30 20 10 5

1 6.35 10.0 22.0 59.0 144. 410. 509. 1010. 1250.

2 5.89 8.99 17.8 50.6 84.4 327. 485. 660. 1030.

5 4.83 6.96 14.4 30.0 71.1 117. 192. 337. 580.

10 4.50 6.10 13.0 20.0 32.6 62.2 83.2 153. 226.

20 4.20 5.40 8.84 12.0 19.6 36.0 40.2 68.0 73.4

25 4.00 5.40 8.10 10.0 17.0 28.0 34.0 47.0 62.5

30 3.80 5.08 7.60 10.0 14.0 24.4 26.4 45.0 55.9

40 3.40 4.80 5.82 7.90 12.0 17.0 21.0 36.4 47.1

50 2.85 4.20 5.10 7.00 11.0 15.0 18.0 34.0 39.5

60 2.60 3.40 4.80 6.40 9.78 13.0 16.8 26.0 33.9

70 2.25 2.90 4.08 6.06 8.56 12.6 14.0 21.0 29.3

75 2.15 2.70 3.90 5.90 8.00 12.0 12.0 20.0 27.0

80 1.99 2.50 3.60 5.54 7.70 11.0 12.0 18.0 24.4

90 1.46 1.92 3.02 5.02 6.70 9.60 11.0 17.0 19.5

95 1.31 1.58 2.40 4.58 6.22 9.06 11.0 14.6 16.6

98 1.15 1.30 2.37 4.10 6.00 8.10 9.95 13.0 15.5

99 1.15 1.20 2.20 4.10 6.00 8.10 9.70 13.0 15.5
Appendix 4 125

03271800 Twin Creek near Ingomar, Ohio

Years analyzed = 37

Climatic year range = 1962–98

[APEE, annual percentage equaled or exceeded; ft3/s, cubic foot per second; Sep, September; Nov, November]

Sep–Nov daily mean streamflow (ft3/s) that was equaled or exceeded the indicated percentage of time at APEE level

APEE 95 90 80 70 50 30 20 10 5

1 11.6 16.8 36.8 89.2 248. 1210. 1560. 2880. 4370.

2 10.8 15.9 25.5 74.1 177. 817. 1430. 2570. 3250.

5 10.6 12.3 19.3 48.6 104. 440. 650. 1130. 1700.

10 9.31 11.6 15.0 25.7 64.8 192. 287. 402. 638.

20 6.20 9.69 11.0 20.2 35.2 92.2 112. 157. 219.

25 6.20 8.72 10.6 19.4 27.0 42.4 85.4 110. 195.

30 6.20 8.05 10.6 17.7 24.4 32.4 64.7 92.5 162.

40 5.80 7.42 9.61 15.0 19.0 24.7 36.1 64.8 91.2

50 4.96 6.28 8.48 13.0 17.0 20.6 27.2 46.6 79.3

60 4.25 5.08 6.73 8.95 14.8 18.0 21.4 38.0 69.0

70 3.87 4.49 6.05 8.27 13.0 16.6 19.4 28.1 44.7

75 3.60 4.14 5.88 7.60 12.0 15.6 18.4 25.4 38.5

80 3.49 3.98 5.38 7.22 11.0 15.0 16.2 25.0 30.8

90 3.28 3.66 5.09 6.55 9.12 13.0 15.0 19.4 27.4

95 3.12 3.39 4.80 6.12 8.20 11.8 14.2 16.4 26.2

98 2.77 3.14 4.60 5.87 7.52 10.6 12.8 15.4 24.3

99 2.77 3.14 4.48 5.52 7.10 10.0 12.8 15.4 23.5

03272700 Sevenmile Creek at Camden, Ohio

Years analyzed = 36

Climatic year range = 1971–2008

[APEE, annual percentage equaled or exceeded; ft3/s, cubic foot per second; Sep, September; Nov, November]

Sep–Nov daily mean streamflow (ft3/s) that was equaled or exceeded the indicated percentage of time at APEE level

APEE 95 90 80 70 50 30 20 10 5

1 7.07 10.7 25.6 55.9 169. 511. 801. 1060. 1420.

2 6.25 9.24 15.4 36.7 118. 437. 573. 826. 1140.

5 5.65 6.97 9.82 21.9 67.6 178. 277. 384. 493.

10 4.86 5.30 7.50 13.3 33.1 86.3 118. 179. 242.

20 3.67 4.27 5.25 9.43 21.3 36.6 56.8 83.9 94.8

25 3.56 3.94 4.82 7.84 17.5 24.9 41.3 69.6 79.5

30 3.53 3.67 4.54 7.31 12.4 21.3 36.8 59.9 70.3

40 3.24 3.51 4.05 5.92 9.02 14.9 17.6 43.4 51.7

50 2.59 3.07 3.60 5.50 7.25 9.47 13.6 35.9 43.2

60 2.32 2.56 3.16 3.86 6.26 7.82 11.0 28.5 36.9

70 1.69 2.17 2.66 3.42 4.99 6.68 9.48 24.1 29.8

75 1.67 2.01 2.54 3.20 4.50 6.49 8.02 21.6 25.9

80 1.57 1.94 2.40 3.00 3.95 6.33 7.20 17.9 22.7

90 1.46 1.68 2.05 2.51 3.27 5.25 6.26 14.5 17.2

95 1.25 1.59 1.88 2.16 3.10 4.65 5.55 11.6 15.2

98 1.14 1.50 1.74 2.07 2.89 4.49 5.27 10.6 14.0

99 1.14 1.50 1.70 2.01 2.85 4.49 5.22 10.4 14.0
126 Methods for Estimating Selected Low-Flow Statistics and Development of Annual Flow-Duration Statistics for Ohio

04177000 Ottawa River at University of Toledo, Toledo, Ohio

Years analyzed = 36

Climatic year range = 1945–2008

[APEE, annual percentage equaled or exceeded; ft3/s, cubic foot per second; Sep, September; Nov, November]

Sep–Nov daily mean streamflow (ft3/s) that was equaled or exceeded the indicated percentage of time at APEE level

APEE 95 90 80 70 50 30 20 10 5

1 52.7 64.1 97.0 158. 416. 650. 888. 1320. 2150.

2 35.2 56.4 83.2 148. 312. 566. 708. 1290. 2100.

5 26.5 33.8 56.4 79.6 169. 255. 495. 875. 1270.

10 18.2 28.2 35.1 60.8 96.5 152. 284. 490. 769.

20 8.51 17.6 23.6 30.2 40.1 76.8 119. 177. 266.

25 7.18 15.7 21.0 25.0 34.5 49.3 83.6 134. 215.

30 6.43 13.4 17.0 21.1 30.0 42.0 66.7 113. 172.

40 5.04 10.0 13.4 16.0 21.7 28.0 47.9 76.8 116.

50 3.76 7.19 11.0 13.0 16.5 22.9 34.0 62.9 81.2

60 2.89 5.25 9.51 10.0 11.9 16.8 26.2 48.0 56.5

70 2.48 4.16 7.17 8.32 9.06 12.9 21.4 34.7 48.6

75 0.86 3.44 5.20 7.03 8.45 11.9 19.8 32.0 44.8

80 0.00 2.48 4.00 5.71 8.15 10.8 16.9 27.9 44.3

90 0.00 1.55 3.20 4.93 6.56 8.79 13.4 19.6 36.1

95 0.00 0.76 2.26 4.04 6.10 7.47 10.6 16.4 22.6

98 0.00 0.64 1.62 2.92 4.36 7.03 9.45 14.9 19.6

99 0.00 0.56 1.54 2.43 4.10 6.65 9.04 14.6 17.9

04184500 Bean Creek at Powers, Ohio

Years analyzed = 49

Climatic year range = 1940–2008

[APEE, annual percentage equaled or exceeded; ft3/s, cubic foot per second; Sep, September; Nov, November]

Sep–Nov daily mean streamflow (ft3/s) that was equaled or exceeded the indicated percentage of time at APEE level

APEE 95 90 80 70 50 30 20 10 5

1 20.0 26.0 45.0 88.0 328. 539. 655. 930. 1080.

2 18.2 25.2 44.2 77.1 245. 469. 535. 766. 890.

5 16.7 24.0 39.4 56.8 139. 229. 351. 474. 520.

10 16.5 22.0 32.0 46.6 77.2 136. 238. 300. 338.

20 14.3 21.0 27.0 34.6 49.6 87.0 144. 182. 206.

25 13.5 20.0 26.0 32.0 42.0 71.0 125. 158. 172.

30 13.5 19.4 24.8 29.0 36.2 65.0 84.8 138. 154.

40 12.0 16.0 21.0 26.0 32.0 55.4 66.0 110. 121.

50 11.5 15.0 18.0 24.0 30.0 47.0 57.0 90.0 96.0

60 10.5 13.0 17.0 21.0 26.8 37.8 45.0 55.0 80.4

70 9.48 11.0 16.0 18.0 22.0 32.0 40.0 43.0 59.8

75 8.60 11.0 14.0 17.0 20.0 28.0 37.0 43.0 54.0

80 7.51 9.50 13.0 15.4 19.0 28.0 32.0 41.0 48.2

90 6.95 8.40 11.0 13.0 17.0 23.0 26.2 34.0 44.6

95 6.60 7.44 10.0 13.0 15.0 20.2 24.6 31.2 37.0

98 6.27 6.67 10.0 11.8 14.8 19.0 24.0 27.8 34.5

99 5.95 6.40 10.0 11.0 14.0 19.0 24.0 27.0 34.5
Appendix 4 127

04185440 Unnamed Tributary to Lost Creek near Farmer, Ohio

Years analyzed = 22

Climatic year range = 1985–2008

[APEE, annual percentage equaled or exceeded; ft3/s, cubic foot per second; Sep, September; Nov, November]

Sep–Nov daily mean streamflow (ft3/s) that was equaled or exceeded the indicated percentage of time at APEE level

APEE 95 90 80 70 50 30 20 10 5

1 0.58 3.63 8.10 21.5 37.0 82.4 106. 138. 201.

2 0.22 1.44 5.38 13.4 28.5 60.3 68.8 78.0 95.1

5 0.08 0.32 1.73 2.53 11.1 21.4 24.5 44.5 46.2

10 0.05 0.15 0.46 0.74 3.50 7.82 12.4 21.4 22.6

20 0.05 0.09 0.19 0.25 0.92 2.66 4.35 6.86 11.8

25 0.04 0.07 0.17 0.22 0.61 1.33 2.70 4.84 9.15

30 0.04 0.06 0.11 0.16 0.36 1.00 2.08 2.98 6.58

40 0.04 0.04 0.06 0.12 0.20 0.52 0.72 1.53 1.87

50 0.03 0.03 0.05 0.08 0.14 0.31 0.50 1.00 1.45

60 0.02 0.03 0.03 0.04 0.12 0.22 0.38 0.71 0.94

70 0.00 0.01 0.03 0.04 0.09 0.16 0.33 0.38 0.74

75 0.00 0.00 0.02 0.03 0.08 0.15 0.30 0.32 0.66

80 0.00 0.00 0.02 0.03 0.07 0.13 0.26 0.30 0.63

90 0.00 0.00 0.01 0.01 0.05 0.10 0.17 0.27 0.38

95 0.00 0.00 0.00 0.01 0.05 0.08 0.14 0.19 0.24

98 0.00 0.00 0.00 0.01 0.04 0.08 0.10 0.16 0.24

99 0.00 0.00 0.00 0.01 0.03 0.07 0.10 0.16 0.23

04189000 Blanchard River near Findlay, Ohio

Years analyzed = 82

Climatic year range = 1923–2008

[APEE, annual percentage equaled or exceeded; ft3/s, cubic foot per second; Sep, September; Nov, November]

Sep–Nov daily mean streamflow (ft3/s) that was equaled or exceeded the indicated percentage of time at APEE level

APEE 98 95 90 80 50 20 10 5 2

1 11.2 18.0 20.6 50.6 506. 2110. 2840. 4470. 5130.

2 8.73 13.8 19.6 45.9 306. 1830. 2530. 3690. 4690.

5 7.37 11.5 14.7 30.6 149. 960. 1500. 2430. 3280.

10 6.55 10.0 12.1 22.8 80.1 378. 831. 1560. 2380.

20 4.83 7.15 10.0 16.4 42.5 183. 282. 626. 1420.

25 4.75 6.30 9.56 14.6 34.5 131. 212. 390. 820.

30 4.19 5.74 8.86 12.0 31.7 107. 169. 257. 635.

40 3.32 5.00 7.09 10.0 25.2 60.3 122. 174. 423.

50 2.83 4.40 6.39 9.18 22.0 47.0 93.3 112. 290.

60 2.51 3.86 5.88 7.89 19.4 40.3 63.7 97.6 194.

70 2.06 3.52 4.93 7.00 17.0 32.5 52.0 86.7 149.

75 1.92 3.12 4.65 6.84 14.5 26.4 47.7 80.1 133.

80 1.49 2.95 4.56 6.26 13.4 24.8 45.1 75.0 118.

90 1.26 2.62 3.38 4.86 11.5 20.1 35.4 50.1 74.0

95 1.07 2.03 2.94 4.17 10.5 18.4 29.1 46.9 58.4

98 0.97 1.83 2.42 3.76 9.44 17.4 23.0 39.0 55.0

99 0.86 1.66 2.26 3.66 9.40 16.4 23.0 38.7 54.4
128 Methods for Estimating Selected Low-Flow Statistics and Development of Annual Flow-Duration Statistics for Ohio

04196500 Sandusky River near Upper Sandusky, Ohio

Years analyzed = 65

Climatic year range = 1921–2008

[APEE, annual percentage equaled or exceeded; ft3/s, cubic foot per second; Sep, September; Nov, November]

Sep–Nov daily mean streamflow (ft3/s) that was equaled or exceeded the indicated percentage of time at APEE level

APEE 98 95 90 80 50 20 10 5 2

1 20.3 26.0 35.6 78.4 391. 1580. 2420. 3020. 4180.

2 11.9 22.0 29.3 65.4 304. 1340. 2220. 2710. 3260.

5 7.28 16.7 23.8 32.6 141. 683. 1180. 1610. 2100.

10 5.68 13.1 16.1 21.8 71.0 450. 775. 835. 1410.

20 4.39 8.16 10.6 15.7 42.6 205. 333. 417. 698.

25 3.95 6.52 9.34 14.2 37.0 146. 264. 343. 554.

30 3.71 5.59 8.62 12.2 31.4 112. 209. 292. 452.

40 3.20 4.80 7.60 9.64 23.2 71.8 124. 187. 322.

50 2.42 4.64 6.46 8.28 19.0 39.6 96.6 151. 254.

60 2.05 3.17 4.38 7.27 14.0 29.0 70.2 105. 196.

70 1.63 2.39 3.35 6.16 12.6 26.4 59.2 80.1 144.

75 1.23 2.33 2.96 5.62 10.0 24.0 50.0 66.7 129.

80 1.12 2.12 2.46 5.02 9.94 22.2 41.8 55.8 117.

90 0.97 1.29 1.96 3.74 8.50 15.2 26.0 34.6 102.

95 0.81 1.15 1.78 2.84 6.50 13.6 19.6 27.1 81.1

98 0.68 1.11 1.56 2.24 5.43 11.8 17.3 25.3 67.0

99 0.60 1.00 1.46 1.92 4.60 11.0 16.4 24.2 31.4

04197000 Sandusky River near Mexico, Ohio

Years analyzed = 57

Climatic year range = 1923–81

[APEE, annual percentage equaled or exceeded; ft3/s, cubic foot per second; Sep, September; Nov, November]

Sep–Nov daily mean streamflow (ft3/s) that was equaled or exceeded the indicated percentage of time at APEE level

APEE 98 95 90 80 50 20 10 5 2

1 27.5 41.7 59.6 96.6 680. 2420. 4330. 6090. 7230.

2 26.5 41.5 55.8 87.9 598. 2090. 4160. 6010. 6980.

5 23.1 36.1 47.1 57.4 232. 1460. 2780. 4860. 5390.

10 17.3 28.0 35.3 45.4 152. 770. 1320. 2210. 3830.

20 15.3 23.3 27.3 37.1 84.2 316. 554. 1050. 2020.

25 15.2 19.6 26.0 36.0 74.0 246. 404. 728. 1710.

30 15.2 16.7 25.2 31.6 66.8 190. 321. 617. 1430.

40 12.4 14.1 22.2 29.0 50.2 125. 235. 419. 1000.

50 10.3 12.0 18.6 22.6 39.0 87.6 147. 273. 574.

60 9.16 11.8 15.8 19.0 33.8 69.8 107. 188. 426.

70 8.61 10.9 13.4 17.0 28.0 58.6 86.8 154. 319.

75 8.50 10.8 12.6 16.0 24.0 57.0 73.6 142. 280.

80 7.99 9.90 10.9 14.2 24.0 52.4 71.4 131. 260.

90 5.98 7.98 9.46 12.0 19.0 45.5 58.0 102. 200.

95 4.30 5.90 7.66 9.37 16.6 37.9 49.4 87.9 174.

98 2.37 5.61 6.78 8.89 14.8 34.3 47.8 62.4 89.6

99 2.37 5.38 5.96 8.52 14.0 34.0 44.4 61.6 89.4
Appendix 4 129

04197100 Honey Creek at Melmore, Ohio

Years analyzed = 33

Climatic year range = 1976–2008

[APEE, annual percentage equaled or exceeded; ft3/s, cubic foot per second; Sep, September; Nov, November]

Sep–Nov daily mean streamflow (ft3/s) that was equaled or exceeded the indicated percentage of time at APEE level

APEE 95 90 80 70 50 30 20 10 5

1 12.9 30.4 50.0 125. 528. 764. 1020. 1290. 2060.

2 11.3 28.6 39.1 100. 387. 685. 936. 1170. 1530.

5 6.71 10.6 20.9 58.9 142. 385. 586. 753. 959.

10 4.65 6.30 13.7 24.8 68.0 216. 265. 505. 641.

20 2.32 3.96 6.87 8.31 22.6 65.8 100. 263. 337.

25 2.09 3.40 4.02 6.78 16.0 47.2 73.0 132. 268.

30 1.74 2.31 3.33 6.10 13.4 38.6 55.3 84.9 222.

40 1.17 1.50 2.28 4.25 9.24 25.0 33.6 58.0 102.

50 0.95 1.18 1.96 2.94 6.60 20.0 24.4 38.8 69.9

60 0.65 0.96 1.60 1.96 5.30 9.86 20.2 28.0 49.4

70 0.44 0.86 1.26 1.50 3.96 8.06 16.1 22.0 36.1

75 0.38 0.73 1.10 1.34 3.60 6.36 15.2 19.6 31.8

80 0.31 0.66 1.00 1.26 3.20 5.54 10.3 17.6 28.9

90 0.19 0.53 0.75 1.01 2.40 3.20 5.11 13.6 15.6

95 0.15 0.38 0.58 0.88 1.46 2.86 4.66 11.8 13.6

98 0.13 0.30 0.51 0.71 1.27 2.63 4.14 10.5 12.6

99 0.13 0.26 0.46 0.65 1.10 2.54 4.06 9.84 12.3

04197170 Rock Creek at Tiffin, Ohio

Years analyzed = 26

Climatic year range = 1983–2008

[APEE, annual percentage equaled or exceeded; ft3/s, cubic foot per second; Sep, September; Nov, November]

Sep–Nov daily mean streamflow (ft3/s) that was equaled or exceeded the indicated percentage of time at APEE level

APEE 95 90 80 70 50 30 20 10 5

1 3.69 4.67 7.58 34.7 131. 295. 373. 609. 962.

2 3.52 4.39 6.77 33.4 91.1 207. 302. 386. 807.

5 2.48 3.33 4.97 10.6 26.6 80.4 118. 246. 489.

10 2.07 2.52 3.89 5.42 11.1 24.8 54.7 133. 200.

20 1.81 2.00 2.78 3.53 4.91 7.99 22.9 40.7 77.3

25 1.68 2.00 2.46 3.30 4.15 6.49 14.7 24.3 52.9

30 1.55 1.88 2.25 2.55 3.24 5.84 12.1 17.6 35.1

40 1.51 1.71 1.90 2.00 2.87 4.82 6.76 11.7 17.7

50 1.17 1.30 1.58 1.90 2.40 3.96 4.94 9.37 12.6

60 1.07 1.20 1.37 1.58 1.94 3.19 3.97 8.02 9.20

70 0.89 1.07 1.20 1.40 1.58 2.49 3.40 7.30 7.61

75 0.84 0.98 1.14 1.21 1.45 2.39 3.06 6.86 7.06

80 0.78 0.93 1.04 1.20 1.37 2.20 2.82 6.09 6.39

90 0.52 0.63 0.87 1.10 1.21 2.08 2.38 3.94 4.85

95 0.42 0.58 0.76 0.94 1.10 1.85 2.23 3.42 4.32

98 0.36 0.53 0.72 0.82 1.00 1.70 2.09 3.23 4.18

99 0.35 0.50 0.70 0.79 1.00 1.70 2.02 3.10 3.81
130 Methods for Estimating Selected Low-Flow Statistics and Development of Annual Flow-Duration Statistics for Ohio

04198000 Sandusky River near Fremont, Ohio

Years analyzed = 83

Climatic year range = 1923–2008

[APEE, annual percentage equaled or exceeded; ft3/s, cubic foot per second; Sep, September; Nov, November]

Sep–Nov daily mean streamflow (ft3/s) that was equaled or exceeded the indicated percentage of time at APEE level

APEE 98 95 90 80 50 20 10 5 2

1 39.4 68.8 86.4 288. 1550. 5670. 8620. 10900. 15300.

2 38.8 61.9 76.3 263. 1190. 4770. 7930. 9620. 14200.

5 33.9 55.2 69.8 149. 694. 2770. 5330. 7160. 10000.

10 26.5 49.6 59.6 96.3 347. 1560. 3470. 4660. 6500.

20 24.4 38.2 47.3 65.3 161. 591. 1350. 2820. 3710.

25 23.0 32.6 44.2 59.8 131. 481. 877. 2330. 2750.

30 21.7 30.8 40.8 54.0 106. 365. 700. 1770. 2230.

40 19.1 28.2 34.8 46.2 83.0 244. 465. 741. 1530.

50 14.7 24.2 32.0 41.0 67.0 178. 367. 494. 1060.

60 12.7 21.4 27.8 36.3 57.0 134. 275. 402. 615.

70 12.6 19.1 22.8 29.9 51.0 107. 216. 341. 455.

75 11.7 17.4 22.0 28.0 47.0 103. 191. 309. 407.

80 11.4 15.2 18.3 26.9 43.2 91.6 151. 238. 358.

90 9.46 13.0 15.0 22.6 35.0 73.8 107. 180. 282.

95 7.41 11.1 13.0 20.4 33.0 60.8 91.6 142. 260.

98 5.41 9.92 11.3 16.5 29.2 52.3 89.1 123. 172.

99 5.41 9.52 11.0 16.0 28.0 50.2 88.8 117. 168.

04199000 Huron River at Milan, Ohio

Years analyzed = 53

Climatic year range = 1950–2008

[APEE, annual percentage equaled or exceeded; ft3/s, cubic foot per second; Sep, September; Nov, November]

Sep–Nov daily mean streamflow (ft3/s) that was equaled or exceeded the indicated percentage of time at APEE level

APEE 98 95 90 80 50 20 10 5 2

1 25.1 28.1 43.2 103. 976. 2150. 3960. 5160. 7720.

2 20.4 25.5 40.2 99.5 685. 1440. 3090. 4330. 5370.

5 16.5 22.3 30.8 51.7 248. 645. 1190. 2010. 3280.

10 14.6 21.4 24.8 41.0 159. 343. 567. 975. 2160.

20 13.2 15.7 19.4 33.8 73.6 159. 286. 463. 811.

25 13.1 14.0 18.4 28.8 60.0 119. 213. 383. 679.

30 12.1 13.7 18.4 27.9 51.4 96.8 182. 296. 598.

40 10.3 12.1 16.4 22.8 36.0 72.6 152. 224. 398.

50 8.77 10.6 15.4 19.8 30.0 62.2 91.8 177. 271.

60 6.79 9.63 12.9 16.0 24.8 51.0 67.1 147. 175.

70 5.87 8.17 11.0 12.0 22.0 45.0 56.7 123. 136.

75 5.59 6.60 8.86 11.0 20.0 41.2 52.4 107. 126.

80 5.21 5.58 8.50 11.0 17.4 38.0 47.0 93.0 110.

90 3.70 4.87 6.38 8.98 14.0 30.6 39.9 49.6 69.0

95 3.28 4.27 5.32 7.24 12.2 24.8 35.4 44.5 63.6

98 3.05 3.85 4.29 6.09 12.0 21.8 32.2 38.9 61.1

99 3.05 3.67 4.08 6.00 12.0 21.0 32.2 38.3 58.0
Appendix 4 131

04199155 Old Woman Creek at Berlin Rd near Huron, Ohio

Years analyzed = 21

Climatic year range = 1987–2008

[APEE, annual percentage equaled or exceeded; ft3/s, cubic foot per second; Sep, September; Nov, November]

Sep–Nov daily mean streamflow (ft3/s) that was equaled or exceeded the indicated percentage of time at APEE level

APEE 95 90 80 70 50 30 20 10 5

1 2.76 5.68 17.6 91.8 184. 248. 335. 438. 449.

2 2.54 4.97 13.3 51.6 102. 161. 212. 306. 426.

5 1.56 3.17 5.87 15.6 46.4 71.2 85.6 113. 152.

10 0.46 1.52 2.42 5.48 20.0 31.8 42.8 59.2 60.7

20 0.26 1.08 1.28 1.94 5.18 11.8 13.6 27.5 34.6

25 0.15 0.89 1.03 1.30 4.10 8.32 9.60 20.2 23.8

30 0.08 0.58 0.78 1.10 3.08 5.99 7.62 15.4 17.0

40 0.02 0.23 0.57 0.73 2.12 3.62 5.47 9.35 12.2

50 0.00 0.06 0.22 0.53 1.30 2.64 4.04 7.02 8.23

60 0.00 0.00 0.07 0.38 0.84 1.88 2.54 4.54 6.41

70 0.00 0.00 0.00 0.14 0.59 1.37 2.18 3.20 4.22

75 0.00 0.00 0.00 0.12 0.42 1.19 1.92 2.68 3.34

80 0.00 0.00 0.00 0.02 0.26 1.05 1.68 2.37 2.81

90 0.00 0.00 0.00 0.00 0.16 0.47 1.19 1.88 2.11

95 0.00 0.00 0.00 0.00 0.00 0.23 0.44 1.00 1.86

98 0.00 0.00 0.00 0.00 0.00 0.11 0.41 0.81 1.68

99 0.00 0.00 0.00 0.00 0.00 0.08 0.41 0.73 1.52

04199500 Vermilion River near Vermilion, Ohio

Years analyzed = 39

Climatic year range = 1950–2008

[APEE, annual percentage equaled or exceeded; ft3/s, cubic foot per second; Sep, September; Nov, November]

Sep–Nov daily mean streamflow (ft3/s) that was equaled or exceeded the indicated percentage of time at APEE level

APEE 95 90 80 70 50 30 20 10 5

1 6.60 19.0 84.0 286. 637. 1430. 1520. 2300. 3340.

2 5.76 14.8 56.2 186. 500. 1070. 1300. 1730. 3060.

5 4.76 8.72 24.6 120. 250. 461. 588. 959. 1310.

10 3.82 7.36 20.6 63.0 132. 225. 294. 503. 563.

20 2.30 4.70 14.6 32.8 49.0 93.2 126. 191. 196.

25 2.00 4.20 13.0 18.0 37.0 70.0 115. 138. 157.

30 1.60 3.80 9.20 13.0 30.4 60.0 90.4 115. 137.

40 1.10 2.90 6.60 8.26 20.2 42.0 60.4 81.2 98.2

50 1.00 2.50 4.70 6.70 15.0 33.0 38.0 56.0 84.0

60 0.08 2.28 3.54 5.32 10.0 20.8 30.8 43.8 71.6

70 0.00 0.80 2.70 4.20 6.92 16.0 25.8 34.8 56.6

75 0.00 0.50 2.30 3.00 4.30 14.0 22.0 30.0 48.0

80 0.00 0.30 1.90 2.24 3.90 10.0 19.0 28.0 32.8

90 0.00 0.20 1.30 1.50 2.92 6.90 9.42 15.4 16.0

95 0.00 0.10 0.77 1.02 2.46 5.80 8.30 11.0 14.0

98 0.00 0.10 0.48 0.90 2.10 5.35 7.38 9.22 12.8

99 0.00 0.10 0.46 0.73 2.10 5.10 7.10 9.10 12.0
132 Methods for Estimating Selected Low-Flow Statistics and Development of Annual Flow-Duration Statistics for Ohio

04207200 Tinkers Creek at Bedford, Ohio

Years analyzed = 46

Climatic year range = 1963–2008

[APEE, annual percentage equaled or exceeded; ft3/s, cubic foot per second; Sep, September; Nov, November]

Sep–Nov daily mean streamflow (ft3/s) that was equaled or exceeded the indicated percentage of time at APEE level

APEE 95 90 80 70 50 30 20 10 5

1 112. 196. 340. 485. 686. 862. 958. 1230. 2030.

2 89.8 171. 273. 361. 474. 726. 798. 1040. 1370.

5 48.8 127. 146. 226. 340. 543. 580. 631. 674.

10 38.0 83.6 103. 126. 238. 303. 349. 385. 494.

20 25.2 50.9 61.8 94.0 127. 163. 179. 237. 283.

25 21.7 43.5 52.8 72.0 103. 122. 143. 191. 215.

30 20.0 38.8 44.4 55.6 85.2 96.8 117. 150. 185.

40 15.2 25.8 37.5 45.3 62.3 73.7 81.0 110. 138.

50 11.1 22.1 32.2 39.1 48.0 60.0 65.2 81.3 117.

60 9.99 19.5 28.0 30.5 37.5 48.7 54.0 67.8 97.2

70 9.38 17.9 24.2 28.0 33.8 41.6 45.6 55.3 76.8

75 8.78 16.2 21.4 26.1 32.0 37.9 40.0 46.2 65.4

80 8.52 14.5 21.0 25.1 28.4 33.0 37.4 42.3 55.8

90 7.59 11.2 18.0 19.3 24.1 27.9 30.8 36.3 40.7

95 7.20 10.3 16.2 18.0 21.1 24.6 27.2 31.2 33.8

98 6.91 10.0 14.3 16.7 19.4 23.8 26.0 28.8 31.1

99 6.65 9.46 13.4 16.0 19.0 23.0 25.6 28.0 30.3

04211000 Rock Creek near Rock Creek, Ohio

Years analyzed = 24

Climatic year range = 1942–65

[APEE, annual percentage equaled or exceeded; ft3/s, cubic foot per second; Sep, September; Nov, November]

Sep–Nov daily mean streamflow (ft3/s) that was equaled or exceeded the indicated percentage of time at APEE level

APEE 95 90 80 70 50 30 20 10 5

1 1.40 2.70 12.0 61.0 208. 578. 904. 1090. 1680.

2 1.21 2.45 9.28 36.6 133. 366. 482. 719. 918.

5 0.72 1.70 5.14 13.6 45.9 134. 181. 419. 540.

10 0.14 1.10 2.14 3.97 21.3 68.4 101. 184. 318.

20 0.00 0.15 1.18 1.75 7.23 29.9 40.2 106. 173.

25 0.00 0.00 0.80 1.45 5.10 17.5 26.0 87.0 125.

30 0.00 0.00 0.60 1.07 2.76 13.7 18.0 64.4 94.6

40 0.00 0.00 0.30 0.51 1.49 7.45 10.2 38.7 52.7

50 0.00 0.00 0.00 0.15 0.80 4.60 7.90 21.0 35.3

60 0.00 0.00 0.00 0.10 0.49 2.58 4.90 7.84 19.3

70 0.00 0.00 0.00 0.00 0.18 0.53 2.44 4.90 14.1

75 0.00 0.00 0.00 0.00 0.10 0.25 2.00 4.60 12.5

80 0.00 0.00 0.00 0.00 0.10 0.25 1.32 4.32 10.8

90 0.00 0.00 0.00 0.00 0.00 0.05 0.40 2.25 3.65

95 0.00 0.00 0.00 0.00 0.00 0.00 0.30 1.85 3.34

98 0.00 0.00 0.00 0.00 0.00 0.00 0.20 1.75 3.08

99 0.00 0.00 0.00 0.00 0.00 0.00 0.20 1.75 2.95
Appendix 4 133

04212000 Grand River near Madison, Ohio

Years analyzed = 49

Climatic year range = 1922–73

[APEE, annual percentage equaled or exceeded; ft3/s, cubic foot per second; Sep, September; Nov, November]

Sep–Nov daily mean streamflow (ft3/s) that was equaled or exceeded the indicated percentage of time at APEE level

APEE 95 90 80 70 50 30 20 10 5

1 37.0 66.0 284. 575. 1630. 4080. 4880. 5900. 8270.

2 36.5 62.6 238. 416. 1460. 3080. 4200. 5210. 6860.

5 31.9 49.0 125. 190. 720. 1930. 2300. 3080. 3990.

10 23.8 28.4 88.2 109. 361. 951. 1670. 1910. 2820.

20 17.1 20.6 33.0 50.6 125. 327. 790. 1130. 1870.

25 15.0 18.0 21.0 35.0 96.0 252. 645. 1010. 1700.

30 13.7 15.0 19.0 31.4 74.8 208. 451. 793. 1460.

40 9.16 11.2 15.0 20.6 39.0 127. 184. 590. 910.

50 6.55 9.10 11.0 14.0 24.0 53.0 107. 352. 582.

60 4.87 6.42 9.00 11.0 18.0 40.0 59.0 150. 400.

70 3.80 5.20 7.28 8.20 13.6 28.0 33.0 112. 239.

75 3.35 4.90 6.70 7.20 12.0 22.0 30.0 87.0 159.

80 2.34 4.50 5.80 6.30 11.0 15.0 25.4 70.8 133.

90 1.33 2.34 3.90 5.42 8.08 11.4 12.2 22.0 34.5

95 0.78 1.16 3.36 4.02 7.20 10.0 11.0 19.0 33.3

98 0.20 0.77 2.02 3.75 5.95 9.00 10.0 16.8 21.5

99 0.20 0.60 1.60 3.20 5.40 8.00 9.80 16.0 21.5

04212100 Grand River near Painesville, Ohio

Years analyzed = 35

Climatic year range = 1974–2008

[APEE, annual percentage equaled or exceeded; ft3/s, cubic foot per second; Sep, September; Nov, November]

Sep–Nov daily mean streamflow (ft3/s) that was equaled or exceeded the indicated percentage of time at APEE level

APEE 95 90 80 70 50 30 20 10 5

1 218. 838. 1510. 3380. 4490. 6320. 7340. 8000. 11400.

2 196. 782. 1310. 2850. 4290. 5530. 6070. 7370. 8920.

5 158. 386. 921. 2050. 2630. 3880. 4510. 5590. 6620.

10 119. 283. 675. 1150. 1670. 2360. 2730. 4130. 4990.

20 82.1 152. 213. 615. 954. 1310. 1870. 2390. 2800.

25 75.4 124. 189. 385. 698. 1030. 1380. 1840. 2310.

30 70.8 92.6 159. 258. 488. 820. 1100. 1670. 1980.

40 59.5 72.5 106. 134. 314. 542. 755. 1220. 1470.

50 42.6 50.2 88.8 104. 203. 374. 454. 871. 1230.

60 27.0 34.3 54.9 79.6 118. 254. 325. 627. 907.

70 15.4 20.8 36.6 53.8 80.6 190. 231. 442. 663.

75 13.6 16.6 30.6 41.0 68.0 147. 179. 318. 524.

80 11.8 14.4 26.5 31.2 58.0 115. 139. 255. 414.

90 9.21 10.7 17.4 24.0 46.2 60.8 103. 140. 282.

95 7.16 9.15 14.7 19.2 28.6 48.6 56.4 97.7 128.

98 6.62 8.61 12.9 16.0 25.0 38.7 50.8 79.8 106.

99 6.62 8.44 12.0 15.0 25.0 38.4 49.8 74.2 97.2
134 Methods for Estimating Selected Low-Flow Statistics and Development of Annual Flow-Duration Statistics for Ohio

04212500 Ashtabula River near Ashtabula, Ohio

Years analyzed = 51

Climatic year range = 1924–79

[APEE, annual percentage equaled or exceeded; ft3/s, cubic foot per second; Sep, September; Nov, November]

Sep–Nov daily mean streamflow (ft3/s) that was equaled or exceeded the indicated percentage of time at APEE level

APEE 98 95 90 80 50 20 10 5 2

1 13.0 19.0 55.0 109. 900. 1680. 2290. 3790. 6050.

2 12.2 15.5 38.5 82.8 444. 1370. 1710. 2490. 3490.

5 6.10 7.53 16.0 45.2 225. 812. 1160. 1420. 2170.

10 3.45 5.52 8.18 23.3 128. 426. 722. 910. 1130.

20 1.65 3.50 4.37 7.06 66.8 204. 370. 493. 794.

25 1.41 2.54 3.28 4.38 38.0 145. 311. 404. 639.

30 1.14 1.30 2.80 3.68 22.8 113. 252. 257. 462.

40 0.14 0.51 1.41 2.40 12.0 84.6 145. 186. 318.

50 0.01 0.32 0.50 1.10 5.40 51.0 83.0 128. 224.

60 0.00 0.06 0.20 0.50 3.20 28.0 56.4 91.9 189.

70 0.00 0.00 0.10 0.18 1.80 14.4 36.0 54.9 156.

75 0.00 0.00 0.00 0.10 1.40 12.4 25.0 44.0 124.

80 0.00 0.00 0.00 0.00 1.00 8.66 14.9 36.5 106.

90 0.00 0.00 0.00 0.00 0.32 3.10 7.47 19.7 39.3

95 0.00 0.00 0.00 0.00 0.20 2.54 6.66 9.92 13.0

98 0.00 0.00 0.00 0.00 0.20 1.62 4.58 6.71 10.9

99 0.00 0.00 0.00 0.00 0.20 1.52 4.38 6.12 10.9

04213000 Conneaut Creek at Conneaut, Ohio

Years analyzed = 73

Climatic year range = 1922–2008

[APEE, annual percentage equaled or exceeded; ft3/s, cubic foot per second; Sep, September; Nov, November]

Sep–Nov daily mean streamflow (ft3/s) that was equaled or exceeded the indicated percentage of time at APEE level

APEE 98 95 90 80 50 20 10 5 2

1 43.4 48.5 140. 441. 1670. 2950. 3590. 7640. 9550.

2 36.4 40.7 122. 302. 1290. 2460. 3080. 4130. 6300.

5 24.5 31.2 55.0 191. 720. 1420. 1780. 2030. 2500.

10 20.8 26.6 41.8 116. 409. 855. 1220. 1420. 1540.

20 17.0 18.0 25.0 39.8 208. 433. 605. 786. 921.

25 15.0 16.0 20.0 35.2 156. 330. 518. 603. 766.

30 12.0 14.8 17.6 22.1 115. 268. 412. 506. 660.

40 8.64 10.8 12.5 17.2 61.2 187. 310. 384. 491.

50 6.18 7.64 9.76 13.8 32.0 131. 208. 261. 366.

60 4.52 6.44 7.70 11.0 23.0 86.6 147. 186. 302.

70 3.63 5.07 6.44 7.64 19.0 58.9 107. 142. 239.

75 3.28 4.38 5.88 6.88 16.0 44.6 85.8 121. 223.

80 3.08 3.95 5.05 6.28 13.4 36.5 68.8 98.4 193.

90 2.15 2.97 3.38 4.47 10.0 25.4 51.9 68.1 114.

95 1.65 2.08 2.78 3.76 8.50 20.4 40.3 44.3 71.8

98 0.91 1.71 2.30 3.09 7.00 17.2 31.7 37.3 43.8

99 0.83 1.71 2.20 3.06 7.00 17.0 29.8 37.3 42.6
Appendix 5 135

Appendix 5. Annual 1-Day and 7-Day Mean Flow-Duration Results for Sites 

with Streamflows that are Subject to Regulation

03086500 Mahoning River at Alliance, Ohio

Years analyzed = 51

Climatic year range = 1942–92

[APEE, annual percentage equaled or exceeded; ft3/s, cubic foot per second]

Daily mean streamflow (ft3/s) that was equaled or exceeded the indicated percentage of time at APEE level

APEE 98 95 90 80 50 20 10 5 2

1 190. 434. 511. 676. 937. 1210. 1360. 1820. 2880.

2 165. 299. 365. 475. 666. 867. 925. 1010. 1130.

5 96.2 148. 186. 231. 365. 493. 597. 620. 725.

10 67.0 86.6 110. 132. 204. 307. 365. 395. 423.

20 29.1 35.0 52.4 69.4 101. 154. 170. 203. 220.

25 24.0 24.0 39.6 54.0 80.0 126. 144. 163. 170.

30 18.0 20.6 30.4 40.2 64.9 104. 121. 135. 151.

40 9.77 11.7 14.4 26.0 46.2 71.2 88.6 98.0 113.

50 3.74 4.80 9.36 15.4 33.0 54.2 65.0 75.4 84.6

60 0.63 2.24 5.70 10.0 23.0 40.4 47.6 57.2 61.9

70 0.00 0.50 2.94 6.56 17.0 28.1 35.6 44.6 48.0

75 0.00 0.06 2.08 4.46 13.0 24.5 30.8 39.6 45.8

80 0.00 0.00 0.26 2.85 10.0 20.1 25.8 34.2 39.8

90 0.00 0.00 0.00 0.00 6.87 13.6 17.2 22.4 25.0

95 0.00 0.00 0.00 0.00 4.10 10.7 14.6 17.0 22.8

98 0.00 0.00 0.00 0.00 3.70 8.96 12.3 14.5 18.8

99 0.00 0.00 0.00 0.00 3.30 8.16 11.7 12.4 16.5

7-day mean streamflow (ft3/s) that was equaled or exceeded the indicated percentage of time at APEE level

APEE 98 95 90 80 50 20 10 5 2

1 145. 275. 379. 431. 618. 751. 849. 1130. 1290.

2 126. 240. 261. 363. 486. 594. 669. 773. 1130.

5 88.5 141. 189. 231. 332. 454. 477. 562. 604.

10 57.8 96.9 119. 142. 247. 312. 384. 400. 447.

20 29.4 40.5 57.2 78.3 129. 197. 244. 272. 279.

25 23.0 29.1 42.7 63.6 94.5 166. 182. 213. 220.

30 19.2 20.2 36.8 50.5 74.9 133. 160. 170. 186.

40 9.33 11.4 16.6 25.6 50.8 91.8 114. 135. 141.

50 4.90 5.43 11.6 17.4 38.0 68.5 85.9 98.7 111.

60 1.22 3.70 6.42 11.9 27.0 50.3 57.4 70.7 81.2

70 0.61 1.66 4.32 7.59 17.1 34.2 43.3 55.3 63.5

75 0.02 0.70 3.24 5.87 14.3 27.9 38.3 49.3 55.3

80 0.00 0.24 1.82 4.06 11.9 23.4 32.7 43.8 48.9

90 0.00 0.00 0.00 0.57 7.14 16.6 22.1 28.7 34.1

95 0.00 0.00 0.00 0.22 5.51 11.9 16.2 20.2 25.2

98 0.00 0.00 0.00 0.00 4.27 9.99 13.8 17.8 20.9

99 0.00 0.00 0.00 0.00 4.07 9.13 12.9 16.2 20.6
136 Methods for Estimating Selected Low-Flow Statistics and Development of Annual Flow-Duration Statistics for Ohio

03093000 Eagle Creek at Phalanx Station, Ohio

Years analyzed = 78

Climatic year range = 1927–2008

[APEE, annual percentage equaled or exceeded; ft3/s, cubic foot per second]

Daily mean streamflow (ft3/s) that was equaled or exceeded the indicated percentage of time at APEE level

APEE 98 95 90 80 50 20 10 5 2

1 440. 559. 735. 856. 1150. 1480. 1590. 1770. 2100.

2 315. 412. 530. 625. 760. 1060. 1180. 1260. 1410.

5 166. 219. 257. 343. 442. 590. 687. 731. 868.

10 89.2 113. 138. 175. 255. 344. 401. 481. 547.

20 47.4 55.0 65.4 93.2 132. 186. 214. 243. 277.

25 35.0 43.4 52.9 75.5 103. 147. 178. 195. 230.

30 28.9 36.8 42.9 57.9 84.4 120. 151. 160. 185.

40 21.7 26.0 30.5 39.0 62.6 88.3 110. 118. 145.

50 16.3 19.9 22.9 27.8 48.0 66.0 84.0 91.6 118.

60 13.3 16.9 18.9 22.8 35.2 52.5 62.1 72.5 94.4

70 10.7 13.0 15.6 19.4 27.0 37.2 46.2 55.3 71.6

75 9.72 12.0 13.9 16.9 23.0 33.2 38.3 49.0 65.1

80 8.30 9.99 12.8 15.0 20.0 27.0 35.1 43.0 56.1

90 6.63 7.85 9.29 11.0 15.0 20.7 24.1 28.9 34.7

95 5.19 6.69 7.12 9.36 12.0 18.1 21.1 25.1 28.1

98 3.58 5.19 6.32 8.16 11.0 16.1 19.4 23.0 25.4

99 2.64 3.90 5.76 7.05 9.90 15.2 18.0 20.8 24.0

7-day mean streamflow (ft3/s) that was equaled or exceeded the indicated percentage of time at APEE level

APEE 98 95 90 80 50 20 10 5 2

1 260. 364. 444. 516. 725. 927. 1050. 1220. 1480.

2 200. 301. 371. 435. 606. 692. 765. 920. 1080.

5 154. 206. 256. 317. 413. 517. 564. 614. 756.

10 93.6 127. 138. 223. 284. 387. 431. 472. 482.

20 55.4 61.5 85.9 118. 168. 248. 276. 315. 355.

25 37.9 51.0 64.9 91.0 133. 197. 215. 254. 291.

30 31.6 40.0 53.3 66.8 105. 162. 185. 239. 253.

40 23.1 27.8 31.4 42.6 72.8 99.3 134. 158. 192.

50 16.9 19.9 24.4 31.8 54.5 75.8 102. 132. 146.

60 13.7 16.8 19.7 23.7 39.6 56.5 78.3 89.4 119.

70 10.6 13.2 16.1 19.4 29.0 43.1 53.0 66.4 96.1

75 9.55 12.0 14.4 17.3 25.1 37.5 43.5 59.1 83.5

80 8.69 10.8 12.7 15.6 21.1 31.5 37.9 48.6 72.6

90 7.29 8.29 9.95 12.1 15.5 23.2 28.7 35.5 48.8

95 6.55 7.16 8.05 10.4 13.5 19.1 23.1 28.7 32.9

98 5.39 6.47 7.24 9.41 12.2 17.3 21.2 25.2 27.3

99 5.02 6.14 6.89 8.76 11.5 16.9 20.2 23.3 26.3
Appendix 5 137

03097500 Meander Creek at Mineral Ridge, Ohio

Years analyzed = 21

Climatic year range = 1930–50

[APEE, annual percentage equaled or exceeded; ft3/s, cubic foot per second]

Daily mean streamflow (ft3/s) that was equaled or exceeded the indicated percentage of time at APEE level

APEE 95 90 80 70 50 30 20 10 5

1 121. 289. 379. 476. 641. 840. 912. 1050. 1130.

2 87.5 178. 278. 329. 445. 565. 747. 787. 791.

5 50.1 82.4 106. 121. 211. 266. 284. 417. 464.

10 7.36 17.3 41.1 56.2 88.0 147. 162. 210. 235.

20 2.05 3.44 4.29 6.64 26.0 53.6 66.2 78.4 87.2

25 1.48 1.52 2.19 3.31 8.75 27.6 39.2 55.3 59.6

30 1.16 1.20 1.58 2.11 5.40 13.1 21.8 38.6 44.8

40 0.81 0.92 1.14 1.56 2.50 5.24 6.54 15.0 22.3

50 0.62 0.80 0.94 1.28 1.60 2.04 3.10 5.20 8.73

60 0.52 0.70 0.80 0.90 1.20 1.64 1.80 3.66 4.91

70 0.51 0.62 0.70 0.70 0.80 1.44 1.66 3.32 4.15

75 0.41 0.52 0.70 0.70 0.80 1.40 1.60 3.04 3.67

80 0.41 0.50 0.60 0.61 0.70 1.30 1.46 2.72 3.09

90 0.40 0.40 0.50 0.50 0.60 1.08 1.26 1.84 2.08

95 0.30 0.32 0.40 0.40 0.60 0.98 1.12 1.60 1.78

98 0.21 0.30 0.31 0.33 0.50 0.82 1.06 1.45 1.50

99 0.03 0.12 0.30 0.30 0.47 0.71 1.00 1.39 1.50

7-day mean streamflow (ft3/s) that was equaled or exceeded the indicated percentage of time at APEE level

APEE 95 90 80 70 50 30 20 10 5

1 110. 257. 321. 374. 537. 629. 723. 1100. 1160.

2 85.4 189. 232. 310. 368. 436. 501. 584. 819.

5 53.5 102. 141. 161. 244. 311. 366. 415. 439.

10 15.3 23.4 61.5 73.9 122. 185. 196. 266. 288.

20 1.86 3.07 5.99 8.20 32.1 70.1 94.3 121. 123.

25 1.28 1.58 2.49 3.97 14.3 47.4 62.8 76.9 92.5

30 1.04 1.09 1.61 2.07 7.63 26.8 33.7 55.3 65.0

40 0.79 0.91 1.13 1.84 3.03 7.03 10.7 28.9 33.0

50 0.69 0.83 0.96 1.39 1.80 2.70 4.44 5.55 15.6

60 0.58 0.75 0.86 0.95 1.20 1.76 2.01 4.16 5.05

70 0.53 0.67 0.73 0.79 0.89 1.50 1.69 3.50 4.27

75 0.50 0.61 0.69 0.75 0.80 1.42 1.62 3.19 3.90

80 0.48 0.55 0.65 0.71 0.76 1.39 1.55 2.85 3.44

90 0.43 0.46 0.54 0.60 0.67 1.17 1.36 1.83 2.34

95 0.37 0.40 0.48 0.51 0.64 1.05 1.26 1.65 1.93

98 0.19 0.35 0.42 0.44 0.60 0.96 1.19 1.52 1.56

99 0.15 0.21 0.39 0.41 0.59 0.93 1.18 1.46 1.55
138 Methods for Estimating Selected Low-Flow Statistics and Development of Annual Flow-Duration Statistics for Ohio

03097550 Mahoning River at Ohio Edison P Plt at Niles, Ohio

Years analyzed = 21

Climatic year range = 1988–2008

[APEE, annual percentage equaled or exceeded; ft3/s, cubic foot per second]

Daily mean streamflow (ft3/s) that was equaled or exceeded the indicated percentage of time at APEE level

APEE 95 90 80 70 50 30 20 10 5

1 1550. 2200. 2780. 3970. 5320. 5650. 5780. 7250. 7730.

2 1240. 1780. 2400. 3170. 3630. 4580. 4820. 5870. 6740.

5 805. 1150. 1750. 2420. 2700. 3560. 3770. 4500. 4960.

10 631. 795. 1150. 1760. 2060. 2970. 3070. 3370. 3700.

20 481. 523. 691. 1040. 1220. 2190. 2270. 2410. 2680.

25 456. 468. 557. 767. 982. 1730. 2060. 2180. 2380.

30 440. 442. 484. 604. 785. 1280. 1850. 1970. 2270.

40 397. 401. 431. 507. 568. 903. 1460. 1650. 1790.

50 356. 369. 393. 419. 486. 724. 1120. 1220. 1410.

60 317. 342. 362. 379. 447. 554. 831. 976. 1160.

70 262. 311. 336. 355. 390. 445. 624. 751. 876.

75 249. 298. 325. 333. 379. 428. 558. 632. 710.

80 238. 275. 302. 310. 351. 418. 510. 558. 598.

90 215. 246. 257. 273. 314. 351. 392. 420. 455.

95 204. 225. 231. 236. 276. 309. 333. 368. 404.

98 194. 201. 209. 226. 257. 282. 299. 341. 353.

99 189. 191. 204. 217. 249. 271. 289. 317. 332.

7-day mean streamflow (ft3/s) that was equaled or exceeded the indicated percentage of time at APEE level

APEE 95 90 80 70 50 30 20 10 5

1 1120. 1350. 2030. 2940. 3480. 4190. 4990. 5570. 5710.

2 981. 1240. 1870. 2670. 3220. 3800. 4190. 4810. 5520.

5 744. 1060. 1540. 2200. 2550. 3310. 3330. 4300. 4730.

10 590. 826. 1140. 1680. 2070. 2870. 2900. 3270. 3820.

20 477. 561. 732. 1050. 1230. 2280. 2340. 2380. 2620.

25 454. 493. 613. 882. 1060. 1760. 2120. 2180. 2350.

30 441. 465. 522. 660. 847. 1350. 1900. 2040. 2190.

40 406. 429. 461. 531. 626. 951. 1550. 1770. 1880.

50 377. 396. 410. 461. 511. 739. 1250. 1420. 1490.

60 331. 354. 383. 404. 477. 602. 974. 1100. 1250.

70 277. 333. 346. 377. 411. 501. 733. 846. 994.

75 259. 315. 337. 359. 396. 442. 641. 733. 890.

80 248. 302. 308. 328. 370. 429. 524. 641. 763.

90 222. 252. 271. 284. 323. 384. 415. 459. 516.

95 211. 236. 239. 252. 291. 338. 376. 410. 443.

98 204. 216. 222. 235. 273. 302. 339. 378. 392.

99 200. 205. 216. 224. 259. 292. 313. 342. 358.
Appendix 5 139

03116000 Tuscarawas River at Clinton, Ohio

Years analyzed = 38

Climatic year range = 1940–77

[APEE, annual percentage equaled or exceeded; ft3/s, cubic foot per second]

Daily mean streamflow (ft3/s) that was equaled or exceeded the indicated percentage of time at APEE level

APEE 95 90 80 70 50 30 20 10 5

1 633. 694. 764. 850. 983. 1210. 1360. 1510. 1610.

2 367. 558. 623. 691. 817. 943. 1070. 1270. 1380.

5 209. 257. 403. 452. 546. 614. 657. 838. 892.

10 145. 161. 219. 254. 316. 398. 450. 511. 559.

20 93.4 108. 121. 143. 169. 218. 270. 289. 377.

25 87.6 91.9 105. 115. 141. 187. 221. 238. 318.

30 70.7 82.2 95.0 99.9 119. 155. 179. 198. 261.

40 59.5 68.7 74.3 82.6 96.0 120. 140. 155. 188.

50 53.4 58.9 66.8 71.0 84.5 98.6 113. 136. 154.

60 46.6 53.8 58.9 63.7 74.0 85.6 95.2 120. 132.

70 42.7 48.9 52.9 59.1 66.0 77.9 80.6 96.6 111.

75 41.6 46.5 49.8 55.5 62.4 74.7 77.6 89.6 103.

80 40.1 45.0 48.8 52.7 59.0 70.6 74.4 84.0 92.2

90 36.7 40.7 42.0 46.7 54.6 65.2 68.6 74.7 77.4

95 33.7 36.9 40.0 42.4 51.0 62.0 64.7 70.1 74.1

98 30.8 34.0 38.0 39.0 48.3 58.7 63.9 68.0 71.0

99 28.8 33.0 36.5 37.8 47.8 57.2 61.1 66.8 70.0

7-day mean streamflow (ft3/s) that was equaled or exceeded the indicated percentage of time at APEE level

APEE 95 90 80 70 50 30 20 10 5

1 436. 542. 588. 630. 807. 962. 1010. 1120. 1160.

2 373. 432. 487. 527. 636. 741. 829. 989. 1060.

5 195. 234. 361. 396. 484. 573. 626. 739. 821.

10 133. 149. 233. 274. 337. 378. 420. 497. 564.

20 93.2 113. 134. 159. 204. 236. 275. 330. 369.

25 88.4 101. 106. 122. 164. 205. 242. 270. 331.

30 73.8 85.9 98.1 108. 138. 179. 199. 221. 286.

40 59.3 68.4 76.4 85.8 103. 133. 153. 173. 210.

50 54.3 61.6 68.6 72.9 89.6 104. 120. 145. 181.

60 46.2 54.8 59.5 66.3 77.1 89.7 102. 133. 145.

70 43.0 49.3 55.3 59.8 67.7 82.1 89.1 107. 123.

75 42.1 47.8 52.6 55.8 64.8 77.6 83.6 97.5 106.

80 41.0 45.7 50.0 53.8 60.6 73.3 80.4 88.4 94.6

90 37.3 41.6 44.3 48.5 56.2 67.2 70.9 77.2 80.4

95 35.7 39.3 41.5 45.7 52.5 63.4 67.3 72.5 75.4

98 32.8 36.1 39.5 42.4 51.3 61.0 64.9 71.0 72.3

99 31.8 35.3 38.9 41.2 50.4 60.2 64.4 69.4 71.0
140 Methods for Estimating Selected Low-Flow Statistics and Development of Annual Flow-Duration Statistics for Ohio

03116200 Chippewa Creek at Easton, Ohio

Years analyzed = 20

Climatic year range = 1961–80

[APEE, annual percentage equaled or exceeded; ft3/s, cubic foot per second]

Daily mean streamflow (ft3/s) that was equaled or exceeded the indicated percentage of time at APEE level

APEE 95 90 80 70 50 30 20 10 5

1 805. 899. 1060. 1110. 1270. 1490. 1690. 2320. 2530.

2 547. 633. 780. 886. 984. 1070. 1160. 1210. 1390.

5 212. 249. 386. 510. 580. 671. 728. 783. 871.

10 119. 127. 166. 252. 336. 415. 486. 542. 634.

20 43.2 49.3 92.4 121. 151. 194. 247. 342. 364.

25 27.7 38.6 71.8 86.3 120. 149. 200. 276. 286.

30 20.3 31.0 56.9 67.3 95.6 125. 159. 228. 242.

40 13.5 24.3 39.9 42.9 69.3 96.3 108. 162. 167.

50 11.4 20.7 27.0 27.6 52.5 77.5 85.0 110. 122.

60 10.0 14.4 19.4 22.0 39.5 54.4 61.9 64.9 98.6

70 9.05 10.3 13.2 17.0 27.9 34.1 43.8 58.5 79.8

75 8.64 9.66 12.2 14.0 24.0 26.9 38.4 49.0 68.5

80 8.22 8.65 11.2 12.3 19.5 24.2 33.2 42.4 51.5

90 6.53 7.16 8.86 9.32 14.5 18.9 22.9 30.0 32.9

95 6.20 6.22 8.04 8.67 12.5 15.7 19.6 26.4 28.9

98 4.80 4.99 6.86 7.99 10.9 13.7 16.7 25.5 27.0

99 3.93 4.60 6.29 7.69 10.3 13.2 15.6 25.2 26.0

7-day mean streamflow (ft3/s) that was equaled or exceeded the indicated percentage of time at APEE level

APEE 95 90 80 70 50 30 20 10 5

1 562. 696. 771. 819. 991. 1240. 1360. 1470. 2400.

2 486. 524. 623. 675. 838. 907. 941. 1200. 1440.

5 208. 224. 377. 447. 551. 623. 654. 740. 747.

10 110. 131. 185. 285. 347. 399. 424. 502. 580.

20 41.1 46.9 96.2 135. 185. 234. 279. 364. 430.

25 26.3 39.9 73.1 101. 140. 174. 226. 317. 351.

30 20.3 33.5 61.3 72.8 112. 151. 168. 272. 287.

40 14.9 25.5 41.6 46.8 77.9 112. 121. 178. 197.

50 11.5 21.1 28.2 29.4 57.0 82.6 96.2 129. 153.

60 9.99 15.8 21.6 22.8 43.5 61.2 75.8 84.2 114.

70 9.33 11.5 14.4 17.6 32.4 40.2 49.7 61.2 89.6

75 8.94 10.2 13.1 15.3 27.1 30.0 45.5 58.7 76.6

80 8.23 9.34 12.5 13.7 22.9 27.2 37.7 51.5 63.0

90 7.47 8.06 10.1 10.7 15.5 20.5 25.0 32.3 38.5

95 6.16 6.58 8.32 9.12 13.9 17.0 21.6 29.0 33.4

98 5.76 6.04 7.25 8.70 11.9 15.0 18.3 27.9 31.4

99 4.92 5.89 7.08 8.23 10.8 13.9 17.5 27.2 29.8
Appendix 5 141

03117000 Tuscarawas River at Massillon, Ohio

Years analyzed = 71

Climatic year range = 1938–2008

[APEE, annual percentage equaled or exceeded; ft3/s, cubic foot per second]

Daily mean streamflow (ft3/s) that was equaled or exceeded the indicated percentage of time at APEE level

APEE 98 95 90 80 50 20 10 5 2

1 1390. 1840. 1930. 2470. 3380. 3980. 4910. 5610. 6540.

2 1010. 1260. 1640. 1990. 2600. 3250. 3590. 4270. 4770.

5 640. 700. 889. 1250. 1710. 2230. 2570. 2930. 3270.

10 412. 471. 541. 704. 1020. 1460. 1810. 1910. 2190.

20 207. 305. 344. 406. 584. 840. 1080. 1160. 1250.

25 172. 255. 281. 331. 469. 650. 856. 934. 977.

30 151. 208. 232. 279. 398. 541. 712. 749. 835.

40 109. 150. 177. 203. 309. 403. 529. 564. 690.

50 97.4 125. 140. 160. 246. 329. 404. 460. 580.

60 90.9 113. 121. 138. 194. 268. 313. 367. 466.

70 85.0 99.5 104. 122. 163. 219. 267. 305. 382.

75 82.0 94.0 96.8 111. 149. 200. 240. 278. 333.

80 79.2 83.6 92.6 104. 137. 183. 215. 246. 301.

90 71.1 73.9 79.7 91.4 114. 146. 170. 200. 230.

95 63.5 66.6 73.1 82.8 102. 132. 147. 173. 195.

98 55.6 62.9 67.2 75.4 95.0 120. 134. 151. 170.

99 52.9 59.1 64.2 72.5 88.7 114. 125. 140. 164.

7-day mean streamflow (ft3/s) that was equaled or exceeded the indicated percentage of time at APEE level

APEE 98 95 90 80 50 20 10 5 2

1 943. 1250. 1480. 1740. 2490. 3220. 3690. 4230. 5050.

2 890. 1060. 1150. 1550. 2010. 2570. 3050. 3500. 3940.

5 584. 697. 786. 1180. 1470. 1870. 2180. 2490. 2850.

10 402. 460. 541. 757. 988. 1410. 1610. 1740. 2020.

20 208. 316. 348. 454. 643. 907. 1130. 1200. 1290.

25 171. 268. 297. 348. 540. 788. 986. 1080. 1100.

30 157. 221. 246. 298. 450. 632. 814. 933. 982.

40 113. 161. 185. 214. 355. 452. 593. 697. 829.

50 98.4 128. 150. 167. 271. 357. 481. 559. 700.

60 91.4 117. 127. 141. 208. 294. 365. 444. 559.

70 84.8 102. 109. 130. 177. 236. 296. 336. 459.

75 83.1 96.7 101. 118. 163. 215. 275. 295. 415.

80 81.5 87.7 95.3 112. 148. 196. 236. 268. 360.

90 71.9 77.0 88.6 97.1 121. 160. 180. 224. 276.

95 64.5 71.6 76.5 88.2 110. 139. 157. 191. 227.

98 57.5 66.1 73.0 80.9 102. 132. 143. 172. 197.

99 56.2 64.0 69.2 76.9 98.7 125. 138. 145. 187.
142 Methods for Estimating Selected Low-Flow Statistics and Development of Annual Flow-Duration Statistics for Ohio

03118000 Middle Branch Nimishillen Creek at Canton, Ohio

Years analyzed = 67

Climatic year range = 1942–2008

[APEE, annual percentage equaled or exceeded; ft3/s, cubic foot per second]

Daily mean streamflow (ft3/s) that was equaled or exceeded the indicated percentage of time at APEE level

APEE 98 95 90 80 50 20 10 5 2

1 90.5 146. 154. 237. 319. 420. 511. 589. 810.

2 67.6 98.3 109. 157. 236. 300. 351. 422. 482.

5 47.1 52.5 67.6 82.3 139. 181. 210. 231. 306.

10 30.5 36.6 42.2 51.2 80.4 122. 144. 165. 193.

20 13.4 22.8 25.8 30.0 49.6 71.3 86.3 98.6 107.

25 9.53 15.6 21.0 25.0 42.0 60.4 73.7 82.1 89.5

30 7.96 11.0 18.0 20.6 36.9 52.1 66.0 72.6 76.8

40 5.11 6.24 11.2 13.8 28.0 40.0 52.2 57.7 62.3

50 3.94 4.90 7.04 9.80 20.0 31.6 39.0 48.6 54.2

60 3.00 3.76 5.07 7.50 15.0 24.4 32.5 39.2 45.3

70 2.34 2.80 3.66 5.86 12.0 20.8 25.4 32.6 38.0

75 1.89 2.40 3.27 4.96 11.0 18.0 22.2 28.6 33.6

80 1.27 2.24 2.88 4.26 9.10 16.4 20.4 25.6 29.3

90 0.58 1.56 2.16 2.98 6.70 13.0 15.4 19.3 22.0

95 0.48 1.31 1.68 2.10 5.60 10.6 13.1 15.9 17.9

98 0.40 1.16 1.30 1.82 5.00 9.24 12.0 12.0 15.4

99 0.39 1.04 1.19 1.65 4.20 8.64 11.1 11.9 13.3

7-day mean streamflow (ft3/s) that was equaled or exceeded the indicated percentage of time at APEE level

APEE 98 95 90 80 50 20 10 5 2

1 66.0 85.1 113. 134. 198. 271. 306. 349. 598.

2 61.9 76.5 85.5 118. 171. 218. 251. 326. 391.

5 44.7 51.9 59.0 91.2 126. 162. 195. 230. 275.

10 30.9 36.7 44.4 57.4 90.0 123. 145. 163. 181.

20 12.8 24.0 27.4 34.4 56.3 84.7 102. 109. 120.

25 9.61 17.4 23.1 27.2 47.0 69.7 86.0 96.5 104.

30 8.43 13.8 19.9 23.8 40.9 61.7 72.0 87.2 90.4

40 5.31 6.51 12.6 15.5 31.3 46.0 57.7 70.1 75.0

50 3.83 5.02 7.10 10.8 23.6 35.8 47.9 56.6 61.9

60 3.14 4.03 4.99 8.17 17.4 27.5 37.4 44.8 53.7

70 2.41 2.83 3.71 6.23 13.6 23.2 29.1 37.0 45.4

75 2.03 2.54 3.38 5.44 11.2 21.0 25.9 33.2 40.3

80 1.56 2.26 3.09 4.49 9.65 18.4 22.7 29.6 37.4

90 0.79 1.68 2.21 3.22 6.87 14.0 17.9 22.3 24.6

95 0.53 1.43 1.87 2.59 6.14 11.3 14.2 18.5 20.7

98 0.42 1.31 1.50 1.95 5.64 9.94 13.0 14.1 17.1

99 0.41 1.19 1.37 1.85 4.86 9.13 11.8 12.8 15.5
Appendix 5 143

03118500 Nimishillen Creek at North Industry, Ohio

Years analyzed = 87

Climatic year range = 1922–2008

[APEE, annual percentage equaled or exceeded; ft3/s, cubic foot per second]

Daily mean streamflow (ft3/s) that was equaled or exceeded the indicated percentage of time at APEE level

APEE 98 95 90 80 50 20 10 5 2

1 373. 698. 762. 920. 1390. 1780. 2180. 2400. 3210.

2 287. 490. 563. 666. 983. 1270. 1510. 1810. 2210.

5 226. 287. 316. 374. 541. 757. 870. 1050. 1180.

10 164. 202. 215. 273. 351. 503. 551. 661. 787.

20 102. 119. 138. 173. 228. 322. 369. 420. 448.

25 89.1 97.7 115. 151. 200. 284. 322. 360. 383.

30 75.8 87.4 99.7 131. 178. 252. 288. 323. 346.

40 54.8 67.4 82.0 102. 145. 210. 238. 269. 294.

50 46.6 54.0 70.7 88.4 125. 183. 198. 229. 255.

60 40.3 47.0 62.5 71.2 107. 150. 171. 200. 220.

70 35.0 39.8 55.4 63.0 91.0 131. 149. 174. 194.

75 32.5 36.8 50.0 59.6 86.0 121. 140. 160. 186.

80 29.8 33.5 47.0 56.0 77.2 114. 130. 150. 170.

90 24.9 30.0 40.3 49.1 70.0 103. 110. 127. 144.

95 22.8 27.4 37.0 45.2 65.0 91.5 106. 116. 133.

98 20.3 24.1 33.6 42.4 59.3 87.8 98.1 110. 120.

99 19.7 23.3 29.8 40.0 57.3 85.0 93.7 106. 113.

7-day mean streamflow (ft3/s) that was equaled or exceeded the indicated percentage of time at APEE level

APEE 98 95 90 80 50 20 10 5 2

1 292. 394. 489. 618. 882. 1140. 1280. 1550. 1700.

2 267. 369. 424. 527. 674. 910. 1020. 1230. 1530.

5 221. 289. 303. 388. 531. 681. 784. 906. 1240.

10 176. 201. 226. 274. 384. 523. 601. 690. 762.

20 105. 120. 147. 189. 260. 372. 407. 477. 507.

25 91.5 104. 123. 167. 229. 316. 349. 428. 470.

30 80.5 91.1 109. 147. 202. 289. 319. 395. 429.

40 56.7 71.3 89.6 113. 159. 233. 265. 318. 355.

50 48.0 57.7 74.9 90.0 138. 197. 226. 266. 302.

60 42.4 50.7 66.1 73.8 114. 166. 189. 224. 262.

70 37.1 45.0 58.1 67.0 96.1 149. 164. 193. 227.

75 36.1 40.9 54.2 63.9 91.3 138. 155. 182. 209.

80 31.7 37.2 49.7 59.8 85.7 128. 145. 170. 193.

90 27.4 31.3 43.8 52.8 73.4 111. 124. 143. 168.

95 25.7 30.1 41.1 48.9 68.3 101. 116. 128. 141.

98 22.2 26.6 36.5 45.5 64.4 91.7 106. 118. 131.

99 21.9 25.6 35.3 44.5 62.9 90.0 99.4 110. 123.
144 Methods for Estimating Selected Low-Flow Statistics and Development of Annual Flow-Duration Statistics for Ohio

03145000 South Fork Licking River near Hebron, Ohio

Years analyzed = 48

Climatic year range = 1940–2008

[APEE, annual percentage equaled or exceeded; ft3/s, cubic foot per second]

Daily mean streamflow (ft3/s) that was equaled or exceeded the indicated percentage of time at APEE level

APEE 95 90 80 70 50 30 20 10 5

1 848. 927. 1040. 1180. 1370. 1680. 1900. 2190. 2410.

2 619. 670. 799. 847. 1070. 1240. 1420. 1690. 1840.

5 321. 375. 435. 530. 687. 827. 889. 995. 1130.

10 179. 211. 271. 326. 407. 536. 564. 603. 675.

20 81.6 104. 131. 159. 235. 293. 348. 379. 412.

25 61.4 76.0 92.3 126. 186. 215. 282. 328. 340.

30 45.7 59.4 69.6 99.2 145. 181. 217. 266. 287.

40 25.5 36.2 52.6 57.0 87.5 110. 134. 165. 186.

50 14.3 23.4 34.8 38.7 54.0 67.6 87.5 115. 134.

60 8.55 16.4 21.9 24.8 36.4 42.3 62.0 74.4 91.0

70 6.99 9.16 15.2 18.0 21.0 29.1 39.2 53.0 61.2

75 6.15 7.69 10.7 15.0 17.0 24.0 31.0 43.3 46.4

80 4.85 5.77 8.82 11.1 14.5 20.2 25.4 35.0 37.0

90 2.70 4.20 6.24 7.58 9.56 14.0 17.2 21.7 24.4

95 1.88 3.43 4.75 6.10 8.20 10.6 15.0 17.1 18.2

98 1.49 2.18 3.82 5.38 6.80 8.35 11.5 15.0 15.2

99 0.98 1.83 3.46 4.92 6.35 7.76 9.97 14.0 14.7

7-day mean streamflow (ft3/s) that was equaled or exceeded the indicated percentage of time at APEE level

APEE 95 90 80 70 50 30 20 10 5

1 453. 547. 643. 789. 936. 1170. 1380. 1490. 1680.

2 402. 499. 540. 614. 802. 906. 1050. 1230. 1280.

5 329. 374. 419. 475. 572. 691. 778. 907. 1000.

10 195. 238. 300. 332. 430. 508. 528. 548. 642.

20 103. 129. 160. 180. 261. 323. 376. 397. 433.

25 66.3 90.6 123. 147. 212. 279. 310. 356. 369.

30 51.2 66.9 92.9 118. 173. 244. 268. 308. 323.

40 28.4 44.7 60.3 79.6 119. 161. 186. 203. 233.

50 16.6 27.4 40.9 47.1 70.3 97.8 127. 148. 171.

60 10.3 19.6 24.5 31.6 44.4 58.0 78.7 109. 122.

70 7.75 10.8 17.8 20.8 26.6 37.5 55.5 71.7 83.3

75 5.91 8.18 14.4 17.2 20.6 29.9 42.6 62.3 65.9

80 5.31 6.86 10.2 13.0 16.1 22.4 29.3 45.5 53.5

90 3.46 4.53 6.45 8.33 10.6 15.9 19.0 26.1 32.2

95 2.51 3.98 4.95 6.77 8.49 12.3 16.6 19.7 21.9

98 1.84 3.01 4.24 5.97 7.66 9.95 13.9 15.9 16.5

99 1.64 2.75 4.06 5.68 7.24 8.88 12.5 15.0 15.3
Appendix 5 145

03156000 Hunters Run at Lancaster, Ohio

Years analyzed = 23

Climatic year range = 1956–78

[APEE, annual percentage equaled or exceeded; ft3/s, cubic foot per second]

Daily mean streamflow (ft3/s) that was equaled or exceeded the indicated percentage of time at APEE level

APEE 95 90 80 70 50 30 20 10 5

1 30.8 46.7 62.1 76.8 104. 123. 128. 172. 196.

2 21.2 27.6 32.9 45.5 66.7 77.8 81.5 90.2 128.

5 11.1 14.6 19.9 26.1 34.7 37.8 44.4 47.9 52.1

10 7.79 9.72 13.8 16.0 21.0 23.1 24.7 28.6 29.0

20 4.32 6.68 8.45 8.97 12.8 14.8 15.2 17.6 19.6

25 3.76 5.76 6.84 7.41 8.70 12.8 13.2 14.6 17.4

30 3.34 5.10 5.70 6.32 7.79 10.8 12.0 13.0 15.4

40 2.42 3.62 4.26 4.52 6.30 8.52 10.0 11.2 12.8

50 1.86 2.58 3.20 3.80 4.55 6.76 7.88 9.32 10.8

60 1.22 1.56 2.36 2.82 3.20 4.72 6.11 8.14 9.10

70 1.00 1.24 1.78 2.20 2.38 3.06 4.65 6.22 6.90

75 0.90 1.14 1.50 1.82 2.10 2.58 4.20 5.46 6.22

80 0.80 0.96 1.38 1.50 1.82 2.18 3.68 4.68 5.44

90 0.70 0.74 1.08 1.10 1.40 1.82 2.46 3.64 4.00

95 0.45 0.54 0.79 1.00 1.20 1.38 2.04 2.74 3.41

98 0.23 0.51 0.68 0.72 1.00 1.28 1.74 2.00 3.20

99 0.17 0.41 0.50 0.67 1.00 1.20 1.69 1.89 3.13

7-day mean streamflow (ft3/s) that was equaled or exceeded the indicated percentage of time at APEE level

APEE 95 90 80 70 50 30 20 10 5

1 20.5 32.9 40.9 56.9 65.4 86.5 104. 140. 195.

2 18.4 27.0 30.8 38.3 52.9 58.7 64.0 82.4 111.

5 12.8 16.0 19.9 24.8 35.3 40.5 44.9 53.8 65.7

10 8.53 10.5 13.9 16.1 22.9 26.8 29.1 32.9 35.2

20 4.45 7.07 8.84 9.96 13.1 16.6 18.7 21.0 21.5

25 3.72 6.01 7.32 8.65 10.5 14.0 16.3 18.0 18.4

30 3.32 5.11 5.92 7.21 8.59 12.1 14.6 16.0 16.3

40 2.39 3.85 4.68 5.12 6.41 9.65 11.4 12.5 13.6

50 1.97 2.85 3.42 3.93 5.09 7.99 9.12 10.5 12.1

60 1.33 1.63 2.61 3.15 3.54 4.81 7.56 9.24 10.2

70 1.02 1.27 1.91 2.39 2.71 3.22 5.57 7.10 7.64

75 0.96 1.18 1.65 2.06 2.36 2.89 5.24 5.76 6.53

80 0.88 1.07 1.52 1.59 2.07 2.38 4.37 4.99 5.95

90 0.71 0.75 1.15 1.25 1.54 1.88 2.74 4.32 4.98

95 0.59 0.69 1.01 1.04 1.35 1.68 2.24 3.25 3.88

98 0.51 0.55 0.75 0.88 1.17 1.31 1.97 2.32 3.47

99 0.38 0.50 0.66 0.77 1.11 1.29 1.79 2.26 3.44
146 Methods for Estimating Selected Low-Flow Statistics and Development of Annual Flow-Duration Statistics for Ohio

03159500 Hocking River at Athens, Ohio

Years analyzed = 46

Climatic year range = 1963–2008

[APEE, annual percentage equaled or exceeded; ft3/s, cubic foot per second]

Daily mean streamflow (ft3/s) that was equaled or exceeded the indicated percentage of time at APEE level

APEE 95 90 80 70 50 30 20 10 5

1 3940. 5760. 6750. 7320. 8420. 9700. 10600. 12500. 14000.

2 3360. 3960. 5230. 5890. 6670. 7250. 8290. 8810. 10500.

5 1890. 2240. 2770. 3170. 3960. 4530. 4810. 5560. 6400.

10 1100. 1390. 1650. 2090. 2370. 2970. 3230. 3860. 4330.

20 601. 762. 965. 1120. 1350. 1720. 1890. 2340. 2590.

25 518. 601. 779. 849. 1140. 1450. 1620. 1960. 2170.

30 436. 521. 635. 693. 938. 1210. 1380. 1680. 1770.

40 262. 306. 421. 488. 619. 848. 1060. 1300. 1400.

50 183. 218. 296. 346. 412. 689. 835. 1030. 1060.

60 114. 147. 216. 241. 302. 497. 618. 779. 855.

70 85.0 104. 157. 182. 225. 353. 452. 620. 682.

75 74.9 91.9 134. 154. 190. 263. 398. 542. 604.

80 66.9 81.2 113. 137. 157. 223. 326. 445. 496.

90 51.5 66.2 88.9 94.1 113. 163. 230. 293. 367.

95 45.6 59.7 72.5 79.3 95.1 134. 179. 238. 311.

98 43.0 56.7 61.4 71.6 87.0 118. 145. 214. 272.

99 40.0 55.2 59.5 68.2 85.0 107. 131. 199. 242.

7-day mean streamflow (ft3/s) that was equaled or exceeded the indicated percentage of time at APEE level

APEE 95 90 80 70 50 30 20 10 5

1 3130. 4120. 4640. 5110. 6110. 7200. 7950. 8960. 13200.

2 2600. 3330. 3870. 4200. 4980. 5690. 6150. 7250. 8850.

5 2000. 2120. 2850. 3310. 3780. 4240. 4560. 4970. 5360.

10 1100. 1510. 1730. 2010. 2580. 2980. 3240. 3740. 4380.

20 618. 770. 1130. 1220. 1550. 1850. 2070. 2490. 2870.

25 527. 611. 873. 960. 1240. 1560. 1810. 2150. 2440.

30 437. 525. 692. 761. 1000. 1340. 1570. 1880. 2130.

40 288. 345. 466. 509. 681. 965. 1180. 1500. 1560.

50 198. 222. 320. 362. 474. 802. 899. 1170. 1220.

60 117. 146. 222. 258. 319. 579. 710. 903. 1020.

70 86.8 112. 163. 190. 241. 387. 489. 705. 800.

75 76.8 97.4 144. 164. 211. 297. 412. 595. 732.

80 69.6 85.6 121. 139. 163. 245. 337. 538. 581.

90 53.3 66.8 94.0 97.1 116. 191. 253. 322. 439.

95 48.6 62.6 77.0 82.9 101. 145. 201. 257. 362.

98 45.7 59.3 68.8 76.4 93.6 130. 172. 230. 320.

99 44.9 56.4 62.3 71.8 88.9 121. 158. 216. 255.
Appendix 5 147

03261500 Great Miami River at Sidney, Ohio

Years analyzed = 82

Climatic year range = 1927–2008

[APEE, annual percentage equaled or exceeded; ft3/s, cubic foot per second]

Daily mean streamflow (ft3/s) that was equaled or exceeded the indicated percentage of time at APEE level

APEE 98 95 90 80 50 20 10 5 2

1 587. 1730. 2520. 2930. 4360. 5660. 6960. 7520. 10100.

2 474. 1200. 1670. 2220. 3340. 4240. 5440. 5920. 7360.

5 315. 612. 1020. 1280. 1980. 2860. 3330. 3580. 4160.

10 243. 388. 511. 703. 1190. 1880. 2030. 2230. 2490.

20 148. 210. 242. 351. 611. 1000. 1240. 1390. 1500.

25 119. 168. 193. 289. 478. 782. 972. 1110. 1220.

30 98.7 139. 167. 235. 387. 600. 759. 915. 960.

40 56.4 95.8 108. 146. 240. 427. 547. 600. 699.

50 45.3 65.8 77.0 105. 179. 314. 379. 469. 515.

60 39.3 51.5 59.3 71.4 127. 214. 289. 357. 394.

70 32.7 42.2 46.3 56.1 89.5 171. 225. 248. 287.

75 30.5 38.3 43.8 50.5 79.3 151. 192. 209. 259.

80 26.7 36.1 40.3 46.6 66.1 133. 159. 180. 232.

90 21.0 30.2 33.2 36.0 53.9 89.6 118. 128. 170.

95 19.3 26.0 28.1 32.0 47.6 75.5 95.8 108. 146.

98 16.7 18.4 23.2 27.3 43.8 65.8 84.4 102. 126.

99 14.5 15.9 21.4 26.2 41.8 63.3 75.1 97.6 123.

7-day mean streamflow (ft3/s) that was equaled or exceeded the indicated percentage of time at APEE level

APEE 98 95 90 80 50 20 10 5 2

1 471. 1280. 1530. 2220. 3250. 4360. 5180. 6090. 7930.

2 370. 969. 1340. 1850. 2680. 3360. 4020. 4630. 6680.

5 309. 630. 903. 1270. 1970. 2530. 3060. 3400. 4000.

10 230. 317. 552. 764. 1220. 1830. 2020. 2280. 2520.

20 142. 230. 256. 388. 665. 1150. 1290. 1440. 1550.

25 122. 185. 196. 306. 568. 915. 1100. 1180. 1290.

30 99.0 154. 167. 249. 442. 724. 937. 1030. 1080.

40 55.5 95.7 114. 161. 292. 525. 639. 756. 813.

50 46.7 72.0 81.7 111. 198. 356. 464. 547. 608.

60 40.7 49.5 60.7 78.0 138. 261. 340. 434. 486.

70 34.2 42.6 46.8 58.1 96.9 193. 260. 304. 337.

75 31.2 38.1 43.9 53.5 81.8 172. 220. 237. 285.

80 27.7 36.7 41.2 48.2 70.7 151. 183. 199. 258.

90 22.6 30.3 33.0 37.1 55.3 98.9 124. 136. 213.

95 19.7 27.3 29.5 32.2 48.5 82.0 104. 116. 170.

98 17.6 19.4 26.2 29.5 44.5 72.8 91.5 105. 141.

99 16.7 18.6 25.4 28.7 43.0 67.1 83.6 103. 137.
148 Methods for Estimating Selected Low-Flow Statistics and Development of Annual Flow-Duration Statistics for Ohio

03261950 Loramie Creek near Newport, Ohio

Years analyzed = 44

Climatic year range = 1965–2008

[APEE, annual percentage equaled or exceeded; ft3/s, cubic foot per second]

Daily mean streamflow (ft3/s) that was equaled or exceeded the indicated percentage of time at APEE level

APEE 95 90 80 70 50 30 20 10 5

1 455. 953. 1180. 1550. 1750. 2090. 2210. 3160. 3300.

2 365. 473. 836. 1020. 1330. 1550. 1790. 2390. 2520.

5 202. 279. 406. 548. 803. 978. 1160. 1290. 1370.

10 95.1 139. 191. 247. 360. 514. 577. 663. 766.

20 35.8 55.0 72.8 98.7 155. 218. 251. 294. 329.

25 24.4 37.1 49.5 71.3 111. 164. 183. 212. 236.

30 17.5 23.0 40.2 53.5 80.1 116. 137. 168. 191.

40 8.10 10.9 20.6 25.5 41.8 65.5 79.6 103. 122.

50 3.90 5.18 10.0 14.0 26.0 41.0 48.5 62.0 82.4

60 2.40 3.65 6.20 8.52 14.4 23.5 32.0 41.5 49.0

70 1.67 2.55 3.30 4.41 7.23 12.4 19.0 26.0 33.7

75 1.38 1.58 2.80 3.38 5.30 9.15 15.0 20.5 27.6

80 1.02 1.26 2.30 2.65 4.25 6.95 11.0 17.0 21.8

90 0.49 0.83 1.00 1.69 2.33 3.56 5.42 7.37 12.2

95 0.27 0.55 0.78 1.12 1.75 2.70 3.33 4.56 7.27

98 0.24 0.45 0.68 0.84 1.32 2.42 2.70 3.62 4.24

99 0.22 0.33 0.59 0.73 1.17 2.10 2.47 3.23 3.77

7-day mean streamflow (ft3/s) that was equaled or exceeded the indicated percentage of time at APEE level

APEE 95 90 80 70 50 30 20 10 5

1 328. 562. 775. 925. 1160. 1460. 1570. 2130. 2500.

2 271. 393. 619. 744. 916. 1130. 1340. 1550. 1880.

5 191. 254. 401. 502. 704. 829. 928. 1100. 1200.

10 120. 160. 205. 308. 399. 525. 584. 635. 769.

20 40.7 66.5 112. 144. 190. 306. 331. 399. 456.

25 27.7 49.4 77.2 101. 141. 232. 266. 314. 347.

30 20.2 26.3 56.6 72.4 105. 176. 198. 247. 281.

40 10.8 12.2 27.3 33.3 59.3 99.6 113. 152. 193.

50 4.39 6.30 15.6 16.9 34.9 57.3 72.6 103. 129.

60 2.91 4.31 7.46 10.6 18.0 32.0 46.0 57.1 78.4

70 1.95 2.49 4.04 5.19 8.80 18.0 29.2 36.9 50.7

75 1.49 1.75 3.02 3.94 6.32 13.3 19.7 30.1 39.5

80 1.16 1.27 2.33 3.25 5.14 9.67 16.4 23.4 29.6

90 0.71 0.93 1.42 2.06 2.68 4.53 6.70 11.4 16.1

95 0.35 0.58 1.04 1.37 2.01 3.17 4.47 7.00 10.6

98 0.26 0.51 0.82 1.00 1.73 2.84 3.41 5.18 8.10

99 0.24 0.49 0.81 0.88 1.49 2.56 3.10 4.29 5.52
Appendix 5 149

03262000 Loramie Creek at Lockington, Ohio

Years analyzed = 91

Climatic year range = 1916–2008

[APEE, annual percentage equaled or exceeded; ft3/s, cubic foot per second]

Daily mean streamflow (ft3/s) that was equaled or exceeded the indicated percentage of time at APEE level

APEE 98 95 90 80 50 20 10 5 2

1 406. 847. 1580. 1900. 2900. 3640. 4340. 4780. 5510.

2 311. 592. 1200. 1420. 1980. 2670. 3280. 4060. 4220.

5 165. 296. 477. 709. 1070. 1530. 1800. 2040. 2230.

10 96.5 128. 207. 318. 526. 820. 972. 1080. 1250.

20 38.0 51.7 70.1 125. 222. 338. 459. 499. 573.

25 31.3 38.0 50.0 89.9 153. 241. 336. 374. 414.

30 21.0 30.3 40.1 66.5 114. 196. 250. 292. 326.

40 12.4 17.0 20.0 39.6 67.0 121. 148. 191. 219.

50 8.74 10.0 13.2 21.8 44.0 76.7 103. 126. 148.

60 6.61 7.88 8.72 15.0 25.0 55.2 68.9 83.8 100.

70 5.54 6.92 7.53 9.78 16.8 37.6 48.8 57.4 78.2

75 4.48 6.51 6.86 8.35 13.0 30.0 41.8 50.8 68.7

80 4.25 5.41 6.12 7.44 12.0 23.8 36.8 45.8 59.3

90 3.32 3.99 4.55 5.68 8.76 15.6 22.5 34.2 42.1

95 2.49 2.97 4.02 4.60 7.50 12.0 17.3 29.0 38.6

98 1.54 2.58 3.22 3.94 6.83 9.81 15.0 23.8 33.2

99 0.91 2.08 2.88 3.70 6.27 9.42 13.0 21.9 31.1

7-day mean streamflow (ft3/s) that was equaled or exceeded the indicated percentage of time at APEE level

APEE 98 95 90 80 50 20 10 5 2

1 298. 582. 935. 1240. 1800. 2520. 3160. 3330. 4270.

2 203. 529. 762. 986. 1480. 1930. 2330. 2700. 3020.

5 145. 288. 551. 705. 980. 1340. 1580. 1870. 1960.

10 93.2 140. 259. 379. 572. 877. 987. 1060. 1230.

20 43.1 56.0 81.9 164. 293. 464. 564. 687. 733.

25 32.2 42.7 57.3 124. 219. 358. 454. 514. 577.

30 22.4 31.4 40.7 87.8 157. 274. 375. 413. 472.

40 12.3 18.7 21.7 47.4 84.7 169. 216. 266. 330.

50 8.79 10.4 13.4 25.2 48.6 105. 133. 170. 214.

60 6.80 8.00 9.44 17.4 30.3 66.4 90.4 111. 144.

70 5.60 6.97 7.91 10.4 18.9 46.3 65.3 76.5 103.

75 4.65 6.57 6.92 8.73 15.2 35.2 52.5 63.5 87.7

80 4.24 5.36 6.19 7.53 12.4 27.1 42.4 53.5 72.7

90 3.28 4.17 4.83 5.67 9.04 17.7 26.3 39.7 49.4

95 2.59 3.37 4.11 4.77 8.04 13.3 20.6 34.5 42.2

98 2.47 2.92 3.84 4.19 7.29 11.1 18.3 29.4 38.0

99 2.40 2.78 3.71 4.01 6.84 10.1 14.9 27.6 36.2
150 Methods for Estimating Selected Low-Flow Statistics and Development of Annual Flow-Duration Statistics for Ohio

03262700 Great Miami River at Troy, Ohio

Years analyzed = 46

Climatic year range = 1963–2008

[APEE, annual percentage equaled or exceeded; ft3/s, cubic foot per second]

Daily mean streamflow (ft3/s) that was equaled or exceeded the indicated percentage of time at APEE level

APEE 95 90 80 70 50 30 20 10 5

1 2690. 4360. 6370. 7050. 8110. 9860. 10800. 12400. 14200.

2 1890. 3160. 4120. 5030. 5910. 7260. 7670. 9940. 11400.

5 1000. 1490. 2270. 3060. 3740. 4810. 5310. 5910. 6490.

10 598. 784. 1260. 1640. 2220. 2860. 3180. 3560. 3930.

20 338. 369. 594. 767. 1030. 1420. 1730. 2080. 2290.

25 272. 323. 447. 586. 821. 1150. 1320. 1590. 1830.

30 222. 252. 394. 495. 662. 911. 1020. 1320. 1480.

40 151. 187. 274. 334. 450. 639. 696. 939. 1060.

50 109. 129. 191. 222. 350. 467. 531. 708. 761.

60 79.1 92.9 143. 161. 223. 349. 397. 516. 587.

70 66.3 69.2 104. 120. 154. 253. 313. 383. 425.

75 57.2 63.1 91.9 103. 123. 205. 274. 314. 377.

80 52.4 57.6 79.5 89.9 106. 189. 234. 267. 327.

90 35.7 45.5 61.4 74.3 86.3 131. 159. 205. 245.

95 30.5 39.1 52.3 63.1 77.5 107. 134. 180. 198.

98 28.0 33.1 44.1 53.2 69.8 97.8 114. 144. 169.

99 24.6 30.7 39.7 49.3 67.2 91.2 106. 137. 157.

7-day mean streamflow (ft3/s) that was equaled or exceeded the indicated percentage of time at APEE level

APEE 95 90 80 70 50 30 20 10 5

1 1980. 2600. 4420. 5120. 5780. 6610. 7690. 8750. 11000.

2 1590. 2230. 3660. 4080. 4750. 5320. 6400. 7180. 7530.

5 1010. 1430. 2120. 2880. 3410. 4110. 4600. 5430. 6280.

10 626. 840. 1390. 1640. 2110. 2820. 3080. 3730. 4180.

20 340. 390. 625. 893. 1250. 1840. 1970. 2280. 2410.

25 271. 323. 499. 728. 973. 1320. 1610. 1930. 2090.

30 216. 251. 425. 564. 793. 1150. 1320. 1600. 1720.

40 158. 195. 296. 357. 541. 748. 879. 1210. 1270.

50 108. 136. 201. 230. 384. 544. 633. 858. 927.

60 81.4 97.6 148. 177. 245. 405. 451. 626. 706.

70 67.4 69.7 109. 123. 164. 270. 370. 461. 496.

75 56.4 64.4 88.4 108. 130. 239. 313. 363. 422.

80 52.5 60.2 83.7 94.6 107. 201. 258. 302. 371.

90 37.6 45.9 65.3 75.4 89.4 146. 178. 220. 280.

95 31.9 38.7 54.5 64.3 80.6 112. 151. 190. 228.

98 29.9 36.0 51.0 57.9 74.1 102. 134. 161. 193.

99 28.3 34.5 46.9 55.3 71.3 101. 126. 147. 187.
Appendix 5 151

03263000 Great Miami River at Taylorsville, Ohio

Years analyzed = 87

Climatic year range = 1922–2008

[APEE, annual percentage equaled or exceeded; ft3/s, cubic foot per second]

Daily mean streamflow (ft3/s) that was equaled or exceeded the indicated percentage of time at APEE level

APEE 98 95 90 80 50 20 10 5 2

1 1300. 3450. 5240. 6220. 9870. 12600. 15100. 17200. 19700.

2 962. 2270. 3870. 4590. 7240. 9660. 12000. 13900. 16600.

5 608. 1370. 2020. 2590. 4190. 6120. 7090. 7470. 8200.

10 475. 801. 1030. 1410. 2380. 3640. 3990. 4490. 4720.

20 313. 420. 506. 793. 1220. 1900. 2400. 2650. 2910.

25 269. 353. 421. 618. 958. 1510. 1930. 2140. 2350.

30 188. 289. 347. 503. 794. 1260. 1490. 1790. 1960.

40 123. 192. 229. 365. 554. 894. 1080. 1290. 1410.

50 91.5 140. 168. 243. 388. 665. 825. 980. 1030.

60 82.9 106. 121. 170. 275. 500. 594. 766. 824.

70 74.1 88.8 94.5 128. 191. 386. 488. 573. 647.

75 68.3 80.4 88.2 110. 166. 343. 417. 479. 568.

80 65.3 72.1 79.9 100. 146. 283. 382. 399. 509.

90 47.2 62.2 69.0 78.4 120. 200. 261. 308. 388.

95 41.3 54.6 60.6 66.7 100. 168. 223. 260. 354.

98 38.4 46.3 54.0 61.2 93.0 142. 185. 213. 325.

99 37.1 42.7 51.9 57.0 87.6 136. 176. 203. 320.

7-day mean streamflow (ft3/s) that was equaled or exceeded the indicated percentage of time at APEE level

APEE 98 95 90 80 50 20 10 5 2

1 1060. 2600. 3380. 4600. 6900. 9570. 10600. 13800. 15300.

2 794. 2180. 2880. 3860. 5520. 7230. 9010. 10600. 14300.

5 568. 1380. 1940. 2540. 3950. 5580. 6390. 7550. 8110.

10 444. 712. 1090. 1570. 2530. 3710. 4220. 4610. 4830.

20 299. 429. 551. 837. 1430. 2230. 2610. 2850. 3360.

25 267. 356. 401. 647. 1150. 1810. 2230. 2390. 2690.

30 179. 301. 352. 554. 868. 1490. 1910. 2120. 2210.

40 129. 187. 252. 393. 591. 1010. 1300. 1560. 1640.

50 96.1 140. 187. 260. 421. 737. 945. 1140. 1250.

60 83.3 105. 123. 181. 293. 566. 674. 850. 992.

70 74.7 89.1 98.5 135. 207. 433. 569. 637. 743.

75 69.6 81.5 90.1 114. 178. 374. 483. 542. 679.

80 65.9 72.7 80.9 103. 151. 311. 395. 444. 625.

90 50.6 64.2 68.6 80.3 123. 206. 284. 360. 497.

95 41.8 56.2 60.5 69.9 106. 180. 246. 286. 383.

98 39.8 49.5 55.7 66.0 99.0 150. 202. 258. 354.

99 39.2 45.6 53.5 61.5 94.0 145. 187. 234. 329.
152 Methods for Estimating Selected Low-Flow Statistics and Development of Annual Flow-Duration Statistics for Ohio

03266000 Stillwater River at Englewood, Ohio

Years analyzed = 83

Climatic year range = 1926–2008

[APEE, annual percentage equaled or exceeded; ft3/s, cubic foot per second]

Daily mean streamflow (ft3/s) that was equaled or exceeded the indicated percentage of time at APEE level

APEE 98 95 90 80 50 20 10 5 2

1 642. 1790. 2920. 4230. 6000. 7280. 7740. 8940. 9570.

2 483. 1040. 2200. 3040. 4900. 5930. 6870. 7930. 9040.

5 294. 668. 1070. 1550. 2980. 4320. 4880. 5080. 5870.

10 224. 366. 503. 701. 1450. 2390. 2960. 3140. 3460.

20 128. 220. 258. 369. 700. 1080. 1290. 1490. 1560.

25 111. 188. 211. 288. 540. 849. 1040. 1140. 1240.

30 98.4 131. 185. 235. 419. 661. 824. 929. 1000.

40 59.2 82.8 126. 152. 292. 454. 544. 604. 689.

50 42.7 51.8 80.6 112. 209. 331. 398. 459. 500.

60 34.8 43.4 59.6 81.6 146. 250. 307. 358. 399.

70 29.1 37.7 45.2 64.0 106. 182. 236. 266. 331.

75 27.0 31.2 41.2 52.9 88.5 159. 200. 243. 290.

80 24.5 27.1 36.2 46.2 73.0 121. 167. 227. 266.

90 16.0 21.4 23.8 31.8 57.0 90.2 111. 166. 220.

95 12.7 16.5 18.1 25.2 48.3 74.7 92.5 126. 183.

98 10.8 13.1 15.0 21.3 41.3 66.5 76.7 115. 152.

99 7.44 10.1 12.7 19.3 38.0 62.4 73.9 110. 141.

7-day mean streamflow (ft3/s) that was equaled or exceeded the indicated percentage of time at APEE level

APEE 98 95 90 80 50 20 10 5 2

1 431. 1500. 1820. 2750. 4490. 5610. 6250. 8080. 9080.

2 337. 1180. 1480. 2400. 3520. 4490. 5120. 6450. 8670.

5 289. 617. 1060. 1690. 2480. 3360. 3820. 4350. 5130.

10 219. 401. 528. 898. 1600. 2340. 2720. 2940. 3200.

20 122. 224. 276. 430. 836. 1350. 1560. 1760. 1810.

25 106. 176. 216. 330. 623. 1040. 1200. 1460. 1550.

30 93.9 134. 187. 243. 494. 842. 995. 1230. 1270.

40 51.6 81.3 125. 163. 330. 568. 728. 867. 899.

50 41.1 53.1 84.2 114. 219. 404. 504. 587. 651.

60 34.1 42.3 58.3 87.5 152. 285. 357. 438. 517.

70 29.9 38.8 45.0 61.6 114. 211. 273. 313. 367.

75 28.6 31.6 41.1 56.0 91.1 175. 233. 265. 328.

80 26.3 29.2 36.5 47.0 75.9 138. 190. 239. 290.

90 20.6 22.7 25.3 33.1 58.0 97.4 127. 180. 254.

95 16.0 19.3 21.0 28.3 50.3 81.6 101. 130. 218.

98 14.3 15.3 17.6 24.5 44.6 72.1 82.1 121. 174.

99 12.4 13.5 16.2 23.8 43.6 67.8 76.4 115. 154.
Appendix 5 153

03267900 Mad River at St Paris Pike at Eagle City, Ohio

Years analyzed = 36

Climatic year range = 1966–2008

[APEE, annual percentage equaled or exceeded; ft3/s, cubic foot per second]

Daily mean streamflow (ft3/s) that was equaled or exceeded the indicated percentage of time at APEE level

APEE 95 90 80 70 50 30 20 10 5

1 765. 825. 1010. 1300. 1850. 2100. 2340. 2790. 3810.

2 606. 637. 742. 949. 1330. 1590. 1620. 2030. 2190.

5 409. 428. 509. 655. 812. 919. 1080. 1180. 1270.

10 302. 323. 368. 475. 553. 697. 793. 822. 856.

20 218. 233. 263. 325. 403. 482. 554. 577. 595.

25 195. 205. 238. 298. 356. 435. 479. 511. 542.

30 174. 188. 223. 270. 324. 399. 430. 459. 508.

40 154. 164. 196. 216. 286. 330. 363. 384. 442.

50 138. 144. 170. 184. 243. 297. 309. 340. 394.

60 123. 129. 145. 169. 214. 249. 272. 314. 340.

70 110. 120. 130. 154. 185. 215. 234. 284. 303.

75 107. 114. 123. 142. 172. 199. 219. 267. 280.

80 102. 110. 118. 131. 164. 188. 202. 247. 262.

90 92.0 98.8 109. 114. 149. 160. 171. 220. 241.

95 81.9 94.4 105. 111. 137. 151. 162. 209. 227.

98 75.1 88.6 100. 109. 132. 142. 150. 199. 212.

99 73.9 87.5 98.5 108. 129. 140. 148. 194. 208.

7-day mean streamflow (ft3/s) that was equaled or exceeded the indicated percentage of time at APEE level

APEE 95 90 80 70 50 30 20 10 5

1 501. 644. 832. 938. 1230. 1500. 1710. 1970. 2150.

2 437. 544. 677. 818. 1030. 1180. 1320. 1620. 1940.

5 375. 451. 488. 637. 796. 935. 1010. 1180. 1310.

10 324. 333. 391. 462. 586. 731. 791. 842. 886.

20 229. 234. 284. 336. 423. 564. 600. 621. 655.

25 199. 206. 256. 312. 382. 475. 537. 566. 598.

30 182. 191. 235. 283. 353. 434. 466. 516. 548.

40 157. 169. 204. 228. 299. 358. 385. 447. 476.

50 138. 147. 173. 189. 252. 306. 325. 366. 425.

60 120. 129. 146. 168. 222. 262. 281. 335. 379.

70 112. 120. 132. 155. 187. 235. 246. 299. 317.

75 109. 116. 125. 146. 175. 212. 228. 271. 295.

80 103. 110. 117. 133. 166. 194. 207. 252. 270.

90 95.5 100. 111. 116. 151. 161. 177. 226. 250.

95 81.5 95.6 106. 113. 139. 156. 164. 215. 238.

98 76.1 92.2 104. 111. 133. 146. 154. 205. 223.

99 75.1 89.0 103. 110. 132. 145. 151. 199. 215.
154 Methods for Estimating Selected Low-Flow Statistics and Development of Annual Flow-Duration Statistics for Ohio

03269000 Buck Creek at Springfield, Ohio

Years analyzed = 30

Climatic year range = 1915–48

[APEE, annual percentage equaled or exceeded; ft3/s, cubic foot per second]

Daily mean streamflow (ft3/s) that was equaled or exceeded the indicated percentage of time at APEE level

APEE 95 90 80 70 50 30 20 10 5

1 167. 415. 746. 770. 893. 1330. 1480. 1680. 2100.

2 120. 265. 469. 528. 588. 805. 923. 1050. 1220.

5 92.2 125. 257. 278. 318. 412. 449. 538. 692.

10 69.5 98.2 138. 168. 219. 253. 273. 282. 391.

20 49.5 72.3 101. 112. 153. 167. 179. 211. 237.

25 43.8 63.7 88.0 100. 129. 149. 165. 188. 200.

30 39.3 55.2 74.2 90.7 117. 132. 152. 169. 190.

40 32.1 34.9 59.4 75.9 97.5 112. 129. 140. 158.

50 26.1 32.5 49.4 59.0 74.5 90.7 101. 131. 141.

60 22.0 30.7 41.6 49.2 62.0 80.6 84.8 115. 123.

70 19.5 28.0 35.4 42.2 52.9 72.2 82.4 98.5 117.

75 17.6 27.0 30.8 37.9 50.0 66.8 70.8 89.4 105.

80 16.2 21.4 28.6 34.0 47.1 59.4 65.8 82.6 94.8

90 11.3 13.8 24.0 29.0 40.3 56.5 63.2 70.9 80.7

95 7.72 11.8 21.8 26.1 37.0 47.7 52.8 60.0 74.1

98 6.26 6.91 17.1 22.9 31.0 46.3 51.2 54.7 71.5

99 5.73 6.52 16.4 19.8 27.0 43.7 51.2 52.0 66.8

7-day mean streamflow (ft3/s) that was equaled or exceeded the indicated percentage of time at APEE level

APEE 95 90 80 70 50 30 20 10 5

1 121. 226. 359. 466. 582. 712. 860. 1130. 1480.

2 110. 180. 300. 350. 477. 565. 666. 728. 1090.

5 92.2 145. 268. 276. 351. 407. 505. 579. 613.

10 77.5 103. 177. 208. 246. 292. 317. 362. 423.

20 54.5 70.1 113. 127. 168. 192. 223. 247. 311.

25 46.0 64.7 102. 109. 142. 172. 180. 217. 267.

30 41.1 51.2 85.6 97.0 126. 156. 166. 195. 225.

40 32.0 34.6 62.0 81.2 104. 127. 144. 157. 184.

50 25.8 32.7 54.0 65.0 77.8 101. 112. 133. 159.

60 23.9 31.0 44.9 53.8 65.5 86.7 97.5 124. 137.

70 20.0 28.3 39.8 43.5 54.7 76.0 80.3 109. 123.

75 18.3 27.3 32.2 38.1 50.9 71.0 76.3 96.7 115.

80 16.9 21.4 30.0 36.3 47.9 66.3 71.0 86.5 107.

90 11.5 15.0 24.5 29.8 41.6 56.1 63.2 71.9 83.8

95 7.75 12.2 22.9 27.0 37.8 50.9 56.8 62.8 77.2

98 6.52 8.72 19.5 25.0 36.0 47.8 52.0 56.9 73.2

99 5.96 6.97 17.5 24.3 30.2 46.9 52.0 55.7 71.3
Appendix 5 155

03269500 Mad River near Springfield, Ohio

Years analyzed = 96

Climatic year range = 1904–2008

[APEE, annual percentage equaled or exceeded; ft3/s, cubic foot per second]

Daily mean streamflow (ft3/s) that was equaled or exceeded the indicated percentage of time at APEE level

APEE 98 95 90 80 50 20 10 5 2

1 661. 1230. 1300. 1970. 3010. 4300. 5060. 5670. 7980.

2 576. 879. 1040. 1360. 2040. 2710. 3500. 3680. 4690.

5 513. 584. 693. 825. 1210. 1590. 1920. 2280. 2390.

10 360. 442. 531. 590. 897. 1150. 1340. 1530. 1580.

20 285. 323. 356. 423. 613. 822. 921. 1000. 1060.

25 254. 293. 322. 379. 535. 726. 828. 885. 966.

30 211. 266. 291. 339. 491. 667. 753. 802. 859.

40 173. 209. 242. 280. 407. 557. 616. 674. 723.

50 155. 175. 206. 247. 346. 480. 534. 574. 664.

60 141. 160. 191. 220. 286. 407. 449. 507. 567.

70 131. 152. 171. 196. 252. 356. 386. 443. 485.

75 131. 144. 164. 185. 243. 327. 365. 414. 459.

80 128. 136. 155. 178. 224. 311. 344. 397. 431.

90 114. 128. 141. 157. 200. 263. 296. 337. 378.

95 105. 119. 131. 151. 193. 243. 271. 305. 346.

98 94.8 107. 126. 142. 184. 228. 256. 294. 315.

99 89.9 103. 122. 137. 179. 223. 253. 286. 294.

7-day mean streamflow (ft3/s) that was equaled or exceeded the indicated percentage of time at APEE level

APEE 98 95 90 80 50 20 10 5 2

1 573. 856. 984. 1370. 1960. 2880. 3700. 4310. 6000.

2 519. 758. 876. 1090. 1610. 2260. 2710. 3070. 4250.

5 500. 594. 672. 857. 1240. 1630. 2020. 2260. 2630.

10 368. 432. 515. 626. 970. 1210. 1430. 1530. 1560.

20 302. 330. 363. 443. 655. 886. 1010. 1110. 1180.

25 260. 284. 329. 391. 581. 789. 927. 970. 1050.

30 200. 259. 300. 355. 518. 701. 836. 881. 961.

40 173. 211. 243. 291. 421. 599. 676. 738. 759.

50 157. 184. 213. 253. 361. 501. 560. 623. 706.

60 139. 161. 194. 228. 309. 432. 483. 548. 611.

70 134. 154. 177. 200. 263. 374. 411. 471. 512.

75 131. 149. 167. 192. 246. 337. 381. 448. 491.

80 129. 143. 157. 184. 231. 321. 359. 422. 458.

90 116. 129. 144. 166. 206. 274. 305. 359. 401.

95 110. 120. 135. 154. 197. 257. 284. 312. 357.

98 101. 109. 132. 147. 191. 242. 266. 303. 340.

99 100. 105. 127. 142. 187. 237. 259. 296. 327.
156 Methods for Estimating Selected Low-Flow Statistics and Development of Annual Flow-Duration Statistics for Ohio

03270000 Mad River near Dayton, Ohio

Years analyzed = 90

Climatic year range = 1915–2008

[APEE, annual percentage equaled or exceeded; ft3/s, cubic foot per second]

Daily mean streamflow (ft3/s) that was equaled or exceeded the indicated percentage of time at APEE level

APEE 98 95 90 80 50 20 10 5 2

1 858. 1610. 1810. 2410. 3870. 5500. 6610. 7900. 10000.

2 664. 1220. 1350. 1850. 2750. 3940. 4570. 4940. 6200.

5 573. 752. 924. 1100. 1710. 2210. 2690. 3030. 3310.

10 411. 567. 692. 785. 1180. 1580. 1880. 2030. 2300.

20 332. 399. 448. 582. 801. 1090. 1210. 1370. 1460.

25 292. 346. 418. 505. 705. 959. 1110. 1200. 1280.

30 254. 296. 358. 441. 642. 860. 981. 1050. 1120.

40 194. 239. 281. 352. 541. 707. 800. 892. 968.

50 173. 206. 253. 306. 460. 598. 683. 758. 837.

60 163. 179. 221. 264. 398. 519. 576. 670. 709.

70 154. 168. 202. 234. 334. 438. 491. 582. 637.

75 149. 164. 195. 222. 307. 404. 458. 549. 602.

80 147. 160. 185. 213. 279. 378. 425. 517. 564.

90 127. 138. 161. 188. 241. 328. 373. 444. 484.

95 120. 130. 150. 172. 223. 309. 341. 397. 437.

98 107. 124. 141. 164. 213. 293. 322. 347. 405.

99 104. 124. 138. 158. 204. 282. 303. 330. 392.

7-day mean streamflow (ft3/s) that was equaled or exceeded the indicated percentage of time at APEE level

APEE 98 95 90 80 50 20 10 5 2

1 648. 1090. 1290. 1760. 2600. 3780. 4370. 6260. 7410.

2 586. 998. 1150. 1490. 2140. 2980. 3650. 4510. 5370.

5 537. 726. 891. 1160. 1650. 2260. 2610. 3110. 3400.

10 433. 564. 664. 854. 1230. 1650. 1910. 2050. 2150.

20 325. 415. 456. 599. 884. 1160. 1300. 1450. 1580.

25 286. 355. 404. 526. 756. 995. 1200. 1270. 1420.

30 239. 290. 369. 451. 687. 903. 1110. 1150. 1280.

40 194. 240. 285. 357. 571. 756. 878. 948. 1050.

50 177. 212. 257. 311. 479. 618. 737. 816. 923.

60 166. 177. 224. 270. 399. 538. 635. 717. 790.

70 154. 170. 203. 244. 346. 453. 538. 610. 684.

75 151. 166. 197. 226. 313. 421. 494. 579. 653.

80 147. 161. 190. 216. 293. 398. 445. 538. 611.

90 128. 140. 165. 193. 252. 340. 389. 461. 525.

95 121. 132. 150. 176. 228. 317. 359. 402. 457.

98 109. 129. 143. 170. 222. 297. 332. 378. 429.

99 108. 128. 141. 164. 216. 294. 330. 361. 419.
Appendix 5 157

03270500 Great Miami River at Dayton, Ohio

Years analyzed = 96

Climatic year range = 1913–2008

[APEE, annual percentage equaled or exceeded; ft3/s, cubic foot per second]

Daily mean streamflow (ft3/s) that was equaled or exceeded the indicated percentage of time at APEE level

APEE 98 95 90 80 50 20 10 5 2

1 2500. 7590. 10200. 12900. 18700. 24000. 28300. 34400. 36200.

2 2170. 5470. 7870. 9650. 14100. 18800. 21700. 26500. 30600.

5 1580. 3090. 4010. 5510. 9020. 13100. 14300. 14900. 16200.

10 1070. 1930. 2210. 3210. 5040. 7740. 9000. 10100. 10500.

20 800. 1070. 1360. 1880. 2740. 4300. 4860. 5540. 6020.

25 750. 864. 1170. 1510. 2310. 3520. 4090. 4710. 5000.

30 609. 719. 956. 1250. 1970. 2880. 3470. 3930. 4280.

40 354. 528. 672. 912. 1530. 2140. 2500. 2900. 3190.

50 300. 396. 520. 647. 1130. 1630. 1970. 2250. 2480.

60 258. 311. 406. 496. 849. 1330. 1620. 1850. 1980.

70 231. 255. 358. 408. 650. 997. 1270. 1400. 1580.

75 219. 237. 330. 365. 564. 887. 1110. 1270. 1400.

80 209. 219. 297. 336. 492. 796. 983. 1070. 1260.

90 164. 189. 215. 283. 396. 598. 708. 847. 1030.

95 145. 163. 187. 255. 361. 523. 625. 780. 889.

98 131. 139. 165. 233. 324. 461. 549. 697. 790.

99 119. 131. 154. 224. 316. 445. 527. 661. 757.

7-day mean streamflow (ft3/s) that was equaled or exceeded the indicated percentage of time at APEE level

APEE 98 95 90 80 50 20 10 5 2

1 1980. 5620. 7080. 9600. 14500. 18400. 21700. 27000. 29500.

2 1660. 4870. 5740. 7990. 10900. 15400. 18500. 20500. 27300.

5 1490. 2790. 4090. 5110. 7950. 11000. 13300. 13800. 17200.

10 1050. 2060. 2540. 3450. 5260. 7750. 8840. 9680. 10200.

20 770. 1060. 1380. 1980. 3170. 4710. 5480. 6470. 6860.

25 702. 877. 1130. 1620. 2560. 3930. 4610. 5300. 5720.

30 531. 723. 1010. 1350. 2130. 3400. 3820. 4560. 5080.

40 354. 532. 709. 950. 1620. 2480. 2940. 3390. 3660.

50 303. 414. 533. 660. 1230. 1850. 2280. 2470. 2980.

60 269. 311. 405. 505. 873. 1500. 1770. 1920. 2380.

70 233. 257. 362. 429. 694. 1120. 1390. 1600. 1700.

75 224. 236. 344. 383. 593. 974. 1230. 1390. 1530.

80 213. 220. 306. 353. 513. 837. 1030. 1190. 1360.

90 180. 196. 209. 299. 421. 625. 738. 941. 1150.

95 151. 166. 195. 267. 375. 555. 662. 803. 976.

98 138. 149. 183. 247. 352. 484. 579. 743. 898.

99 131. 139. 169. 241. 338. 468. 539. 704. 870.
158 Methods for Estimating Selected Low-Flow Statistics and Development of Annual Flow-Duration Statistics for Ohio

03271500 Great Miami River at Miamisburg, Ohio

Years analyzed = 52

Climatic year range = 1925–94

[APEE, annual percentage equaled or exceeded; ft3/s, cubic foot per second]

Daily mean streamflow (ft3/s) that was equaled or exceeded the indicated percentage of time at APEE level

APEE 98 95 90 80 50 20 10 5 2

1 2760. 4310. 9590. 13000. 18500. 24200. 28400. 35300. 40100.

2 2050. 3340. 6180. 9200. 14300. 18500. 20800. 26300. 34400.

5 1470. 2660. 3600. 5310. 9420. 12600. 14100. 15500. 16300.

10 1070. 1510. 2320. 3050. 5350. 8320. 9840. 10400. 11100.

20 616. 1080. 1300. 1800. 2970. 4540. 5410. 6160. 6230.

25 536. 964. 1070. 1550. 2500. 3670. 4540. 5010. 5370.

30 475. 764. 932. 1380. 2160. 3130. 3850. 4420. 4630.

40 400. 582. 752. 976. 1570. 2370. 3000. 3290. 3680.

50 341. 483. 563. 743. 1210. 1920. 2420. 2550. 2940.

60 304. 397. 486. 598. 931. 1620. 1870. 2160. 2460.

70 277. 334. 417. 526. 763. 1220. 1540. 1730. 2050.

75 266. 318. 376. 485. 677. 1100. 1380. 1510. 1860.

80 253. 309. 349. 462. 616. 1000. 1220. 1310. 1720.

90 232. 265. 295. 377. 500. 752. 863. 1050. 1320.

95 209. 245. 279. 333. 456. 670. 793. 983. 1140.

98 181. 221. 250. 293. 431. 608. 715. 858. 969.

99 168. 210. 240. 280. 421. 598. 689. 824. 917.

7-day mean streamflow (ft3/s) that was equaled or exceeded the indicated percentage of time at APEE level

APEE 98 95 90 80 50 20 10 5 2

1 2060. 3070. 6280. 9610. 13700. 20100. 23800. 29600. 33700.

2 1690. 2860. 5330. 7310. 11600. 15400. 17400. 22000. 28500.

5 1390. 2380. 3390. 4740. 8350. 11300. 12500. 13800. 17600.

10 1070. 1530. 2410. 3120. 5690. 7960. 8970. 10000. 10800.

20 614. 1080. 1320. 1950. 3420. 5050. 6250. 6990. 7540.

25 541. 936. 1090. 1620. 2860. 4420. 5320. 5690. 6250.

30 478. 724. 937. 1320. 2320. 3820. 4510. 5120. 5420.

40 399. 584. 763. 979. 1690. 2640. 3460. 3640. 4220.

50 351. 470. 581. 762. 1270. 2070. 2640. 2810. 3380.

60 313. 399. 493. 617. 985. 1740. 2130. 2350. 2690.

70 279. 331. 437. 542. 802. 1390. 1710. 1870. 2060.

75 268. 323. 387. 516. 705. 1210. 1500. 1630. 1900.

80 252. 308. 358. 465. 639. 1100. 1280. 1390. 1770.

90 237. 275. 305. 389. 525. 795. 902. 1090. 1490.

95 224. 243. 286. 340. 472. 688. 850. 1020. 1260.

98 204. 237. 269. 308. 445. 624. 782. 949. 1160.

99 190. 229. 264. 301. 438. 615. 720. 907. 1050.
Appendix 5 159

03272000 Twin Creek near Germantown, Ohio

Years analyzed = 84

Climatic year range = 1921–2008

[APEE, annual percentage equaled or exceeded; ft3/s, cubic foot per second]

Daily mean streamflow (ft3/s) that was equaled or exceeded the indicated percentage of time at APEE level

APEE 98 95 90 80 50 20 10 5 2

1 414. 1300. 1550. 2200. 3520. 4980. 5500. 5640. 6500.

2 232. 620. 917. 1230. 2260. 3490. 4120. 4570. 5320.

5 115. 325. 439. 639. 1080. 1650. 2050. 2410. 2760.

10 77.7 203. 242. 350. 593. 875. 1000. 1260. 1360.

20 43.3 86.0 113. 169. 293. 463. 507. 622. 711.

25 35.3 61.5 97.5 131. 232. 344. 411. 478. 547.

30 28.3 45.0 76.0 109. 192. 279. 326. 406. 458.

40 16.6 24.3 43.5 71.6 130. 200. 246. 279. 316.

50 13.8 17.3 25.8 46.0 91.5 135. 174. 205. 234.

60 9.05 11.5 15.0 28.0 61.5 95.0 126. 150. 179.

70 6.62 9.25 12.5 18.0 36.9 58.1 81.3 122. 134.

75 6.27 8.64 11.5 15.0 28.8 46.5 70.3 103. 117.

80 5.82 6.78 9.70 13.0 24.5 37.0 60.7 85.9 102.

90 4.11 4.81 6.55 9.10 15.0 26.6 34.4 55.2 74.3

95 3.78 3.95 5.22 7.23 12.0 22.3 28.6 40.0 60.9

98 3.12 3.47 4.13 5.70 11.0 19.0 23.5 33.7 45.5

99 2.82 3.17 3.85 5.30 10.0 17.7 22.5 31.4 41.7

7-day mean streamflow (ft3/s) that was equaled or exceeded the indicated percentage of time at APEE level

APEE 98 95 90 80 50 20 10 5 2

1 179. 789. 902. 1300. 2090. 3030. 3460. 3920. 4940.

2 144. 572. 729. 1040. 1570. 2270. 2610. 3160. 4320.

5 122. 387. 500. 709. 1080. 1530. 1770. 2120. 2460.

10 91.1 212. 266. 398. 699. 1050. 1220. 1370. 1500.

20 50.3 85.1 124. 217. 378. 577. 713. 787. 980.

25 34.8 60.5 97.7 156. 291. 452. 567. 627. 808.

30 28.9 42.6 81.7 119. 234. 357. 458. 531. 636.

40 18.9 24.2 47.1 78.7 154. 242. 306. 365. 474.

50 14.1 17.5 26.1 51.7 103. 156. 204. 261. 291.

60 9.55 11.7 15.4 28.3 67.6 114. 147. 181. 228.

70 6.76 9.68 12.6 18.2 41.4 72.1 94.9 144. 180.

75 6.43 8.39 11.6 16.3 31.0 55.7 75.1 123. 147.

80 6.03 7.31 10.4 14.6 25.6 43.7 63.8 104. 126.

90 4.26 5.06 6.51 9.19 15.8 28.1 36.8 70.8 88.7

95 3.83 4.20 5.45 7.60 12.8 23.7 30.7 47.5 68.3

98 3.31 3.59 4.49 6.36 11.6 20.9 26.3 39.9 51.6

99 2.93 3.31 4.07 6.10 10.8 19.1 25.2 37.2 47.0
160 Methods for Estimating Selected Low-Flow Statistics and Development of Annual Flow-Duration Statistics for Ohio

03274000 Great Miami River at Hamilton, Ohio

Years analyzed = 78

Climatic year range = 1931–2008

[APEE, annual percentage equaled or exceeded; ft3/s, cubic foot per second]

Daily mean streamflow (ft3/s) that was equaled or exceeded the indicated percentage of time at APEE level

APEE 98 95 90 80 50 20 10 5 2

1 6340. 11900. 13500. 16900. 26600. 33700. 38500. 45100. 57000.

2 4420. 8460. 10900. 12400. 19900. 26300. 30000. 36000. 45300.

5 3170. 4370. 6140. 7860. 13400. 17400. 20600. 22100. 23500.

10 1860. 3010. 3700. 4880. 7950. 11300. 13400. 14000. 15200.

20 1250. 1710. 1980. 2880. 4460. 6360. 7490. 8260. 9400.

25 1050. 1420. 1610. 2300. 3680. 5370. 6200. 6830. 7640.

30 789. 1210. 1400. 1930. 3120. 4330. 5400. 6050. 6430.

40 560. 785. 1070. 1340. 2430. 3250. 4150. 4400. 4910.

50 460. 624. 834. 997. 1810. 2530. 3190. 3460. 3810.

60 408. 461. 637. 802. 1360. 1990. 2370. 2770. 3200.

70 362. 420. 506. 667. 993. 1560. 1840. 2350. 2610.

75 342. 402. 448. 589. 847. 1330. 1590. 2130. 2360.

80 328. 379. 419. 536. 756. 1160. 1460. 1960. 2180.

90 286. 328. 358. 468. 605. 888. 1070. 1430. 1780.

95 258. 306. 320. 406. 556. 796. 979. 1230. 1610.

98 220. 272. 287. 377. 493. 735. 865. 1060. 1330.

99 201. 253. 279. 354. 475. 699. 826. 1000. 1260.

7-day mean streamflow (ft3/s) that was equaled or exceeded the indicated percentage of time at APEE level

APEE 98 95 90 80 50 20 10 5 2

1 4150. 8320. 10200. 12300. 19100. 26800. 29500. 38300. 47500.

2 4000. 7450. 8460. 10100. 15700. 21600. 25400. 28500. 42700.

5 2720. 4900. 6040. 6940. 11800. 15900. 19300. 21700. 23700.

10 1900. 3030. 3780. 4920. 8130. 11000. 12800. 14600. 15300.

20 1240. 1780. 2060. 3080. 4910. 7080. 7940. 9090. 10000.

25 1030. 1420. 1660. 2500. 3940. 5880. 6820. 7920. 8620.

30 769. 1240. 1460. 1950. 3330. 5100. 6010. 6830. 7340.

40 563. 815. 1120. 1400. 2550. 3690. 4560. 5220. 5500.

50 473. 644. 871. 997. 1880. 2750. 3440. 4010. 4440.

60 404. 451. 668. 832. 1370. 2170. 2610. 3100. 3740.

70 362. 415. 507. 674. 1060. 1660. 2010. 2580. 2870.

75 343. 403. 468. 603. 904. 1420. 1750. 2220. 2640.

80 328. 390. 425. 550. 782. 1280. 1490. 2030. 2430.

90 295. 331. 365. 467. 651. 943. 1140. 1700. 1950.

95 270. 318. 336. 422. 596. 828. 1030. 1360. 1750.

98 238. 290. 310. 386. 520. 761. 951. 1290. 1570.

99 220. 282. 308. 378. 505. 732. 868. 1240. 1400.
Appendix 5 161

04183500 Maumee River at Antwerp, Ohio

Years analyzed = 56

Climatic year range = 1922–81

[APEE, annual percentage equaled or exceeded; ft3/s, cubic foot per second]

Daily mean streamflow (ft3/s) that was equaled or exceeded the indicated percentage of time at APEE level

APEE 98 95 90 80 50 20 10 5 2

1 4860. 5440. 5920. 8690. 11700. 16300. 17800. 20900. 23700.

2 3240. 4510. 5170. 7010. 10600. 13400. 15100. 16900. 21100.

5 1620. 2650. 3850. 4980. 7210. 9240. 11300. 13600. 14100.

10 1080. 1590. 2020. 2760. 4770. 5740. 7150. 8020. 9580.

20 538. 692. 1170. 1410. 2410. 3540. 4540. 5090. 5780.

25 428. 501. 866. 1060. 1840. 2740. 3660. 4030. 4460.

30 336. 422. 679. 818. 1480. 2290. 2970. 3430. 3500.

40 220. 267. 315. 504. 946. 1530. 1850. 2170. 2570.

50 181. 197. 223. 353. 629. 1010. 1320. 1560. 1810.

60 154. 162. 171. 243. 413. 749. 950. 1120. 1360.

70 126. 135. 151. 192. 304. 527. 708. 769. 947.

75 111. 120. 134. 176. 259. 438. 548. 650. 755.

80 98.6 104. 125. 154. 235. 388. 436. 550. 600.

90 77.5 81.4 99.9 121. 167. 254. 309. 352. 450.

95 58.4 71.3 87.7 103. 141. 208. 256. 291. 388.

98 49.0 62.2 71.0 85.4 122. 176. 204. 253. 327.

99 38.3 55.4 65.9 77.7 116. 164. 188. 241. 277.

7-day mean streamflow (ft3/s) that was equaled or exceeded the indicated percentage of time at APEE level

APEE 98 95 90 80 50 20 10 5 2

1 3970. 4590. 4950. 7000. 10200. 14600. 16100. 19000. 22600.

2 2900. 3430. 4290. 6210. 8980. 11800. 14300. 17200. 18500.

5 1520. 2370. 3240. 5070. 6530. 8760. 9650. 11500. 12900.

10 1000. 1550. 1950. 2670. 4570. 5650. 7080. 7720. 8620.

20 512. 662. 1200. 1460. 2540. 3600. 4590. 5020. 5340.

25 420. 476. 888. 1100. 2100. 2950. 3810. 4110. 4390.

30 335. 403. 701. 946. 1590. 2530. 3060. 3370. 3720.

40 223. 265. 320. 557. 960. 1640. 2070. 2570. 2800.

50 181. 188. 229. 359. 647. 1090. 1490. 1730. 2030.

60 157. 164. 171. 250. 432. 798. 1060. 1200. 1490.

70 123. 138. 151. 198. 320. 574. 764. 857. 1050.

75 111. 123. 142. 179. 279. 472. 652. 744. 914.

80 106. 110. 131. 159. 242. 406. 508. 645. 664.

90 81.8 88.8 104. 124. 184. 291. 338. 406. 471.

95 68.9 73.4 94.2 110. 158. 229. 284. 317. 419.

98 59.5 64.2 76.8 95.7 143. 199. 257. 283. 350.

99 48.4 61.3 73.1 88.1 134. 181. 235. 274. 315.
162 Methods for Estimating Selected Low-Flow Statistics and Development of Annual Flow-Duration Statistics for Ohio

04185000 Tiffin River at Stryker, Ohio

Years analyzed = 74

Climatic year range = 1922–2008

[APEE, annual percentage equaled or exceeded; ft3/s, cubic foot per second]

Daily mean streamflow (ft3/s) that was equaled or exceeded the indicated percentage of time at APEE level

APEE 98 95 90 80 50 20 10 5 2

1 770. 1510. 1630. 1890. 2590. 3700. 4230. 4530. 5780.

2 651. 989. 1320. 1520. 2090. 2980. 3220. 3750. 4130.

5 335. 534. 714. 967. 1430. 1960. 2130. 2280. 2420.

10 220. 337. 414. 629. 983. 1340. 1490. 1560. 1680.

20 93.5 177. 209. 279. 481. 744. 900. 950. 1000.

25 62.5 137. 169. 210. 369. 536. 668. 738. 789.

30 50.0 106. 124. 155. 293. 413. 478. 546. 612.

40 29.5 45.0 67.6 102. 207. 279. 336. 354. 392.

50 24.0 29.8 46.0 64.0 138. 187. 248. 270. 298.

60 18.5 23.5 35.7 46.0 92.9 140. 185. 203. 230.

70 14.5 20.1 28.5 36.0 58.9 104. 131. 141. 164.

75 12.8 18.5 24.9 28.0 49.5 77.0 111. 116. 142.

80 11.5 18.3 20.5 26.4 41.0 63.4 87.6 100. 131.

90 8.70 9.78 14.0 18.0 24.8 42.6 52.3 74.9 99.0

95 6.39 6.91 9.88 15.0 20.0 36.0 41.0 52.2 73.4

98 4.30 5.76 8.14 12.0 17.7 31.6 37.2 43.8 59.7

99 3.62 5.12 7.26 11.0 16.5 31.0 34.8 40.2 57.0

7-day mean streamflow (ft3/s) that was equaled or exceeded the indicated percentage of time at APEE level

APEE 98 95 90 80 50 20 10 5 2

1 684. 1170. 1260. 1580. 2260. 2890. 3490. 3730. 4900.

2 400. 931. 1090. 1270. 1830. 2510. 2670. 3070. 3710.

5 276. 459. 756. 923. 1360. 1800. 1960. 2150. 2320.

10 185. 305. 405. 620. 910. 1270. 1430. 1510. 1570.

20 92.5 185. 224. 312. 508. 726. 909. 937. 1030.

25 61.7 143. 171. 219. 405. 613. 727. 783. 823.

30 50.9 102. 127. 168. 321. 485. 590. 654. 699.

40 29.9 46.1 71.6 102. 227. 316. 409. 455. 490.

50 24.5 29.5 46.8 68.6 142. 206. 277. 312. 345.

60 19.4 24.0 36.1 48.6 99.5 153. 207. 233. 263.

70 15.1 20.0 29.8 38.3 66.9 112. 149. 156. 191.

75 13.4 18.8 24.9 29.3 53.3 82.6 122. 128. 154.

80 11.7 18.0 21.1 28.0 43.1 67.5 99.6 107. 142.

90 8.85 11.1 14.5 18.3 27.0 46.3 56.5 78.9 110.

95 6.62 7.41 10.8 15.3 20.4 37.4 44.7 56.3 81.2

98 4.66 6.03 8.90 13.1 18.5 33.0 39.6 50.0 65.6

99 4.14 5.77 8.48 12.1 18.0 32.7 37.2 46.9 61.9
Appendix 5 163

04187500 Ottawa River at Allentown, Ohio

Years analyzed = 48

Climatic year range = 1924–80

[APEE, annual percentage equaled or exceeded; ft3/s, cubic foot per second]

Daily mean streamflow (ft3/s) that was equaled or exceeded the indicated percentage of time at APEE level

APEE 95 90 80 70 50 30 20 10 5

1 432. 637. 1030. 1120. 1430. 2010. 2210. 2320. 2480.

2 291. 427. 668. 802. 1090. 1370. 1470. 1730. 1820.

5 121. 209. 296. 385. 547. 782. 828. 909. 1040.

10 63.8 77.2 143. 183. 244. 378. 459. 556. 618.

20 35.7 37.9 63.2 80.0 104. 158. 190. 297. 316.

25 26.0 30.0 44.2 63.9 78.5 111. 139. 202. 236.

30 21.1 27.8 35.6 49.0 62.5 83.4 107. 149. 195.

40 17.4 22.9 27.8 36.1 45.6 54.5 72.0 103. 118.

50 15.6 20.0 22.8 27.0 35.0 42.3 47.6 68.2 75.8

60 13.8 18.0 20.8 22.7 28.0 34.0 36.8 47.5 52.9

70 11.4 14.0 18.0 19.7 24.0 28.3 31.0 37.3 41.1

75 11.0 13.8 16.0 18.9 22.0 26.3 29.1 35.0 38.0

80 9.47 12.8 15.8 18.7 20.5 24.0 28.1 32.3 35.1

90 7.47 9.98 13.6 16.0 18.0 21.2 24.8 28.1 31.5

95 6.48 9.26 11.8 15.0 17.0 19.3 23.1 26.2 29.1

98 5.92 8.81 11.0 12.7 16.0 18.0 21.2 25.1 27.0

99 5.64 8.61 9.75 11.7 15.0 17.8 20.0 24.0 25.0

7-day mean streamflow (ft3/s) that was equaled or exceeded the indicated percentage of time at APEE level

APEE 95 90 80 70 50 30 20 10 5

1 293. 376. 657. 794. 1010. 1210. 1440. 1740. 1770.

2 236. 306. 487. 622. 747. 927. 1030. 1270. 1310.

5 119. 221. 357. 430. 541. 673. 723. 851. 978.

10 66.0 86.7 181. 230. 313. 444. 501. 551. 593.

20 33.5 39.1 67.9 98.2 128. 208. 283. 352. 397.

25 29.5 33.9 55.8 71.3 98.9 158. 201. 273. 324.

30 26.9 28.9 40.9 60.1 77.5 118. 144. 218. 261.

40 19.9 23.9 29.7 40.0 53.0 64.4 89.6 136. 173.

50 16.4 21.0 24.7 30.3 40.0 48.2 54.2 86.7 117.

60 14.9 18.9 22.1 24.2 30.6 37.3 42.1 61.3 67.4

70 12.5 15.3 18.5 20.9 24.9 31.1 34.5 43.6 50.0

75 11.7 14.3 17.7 20.1 23.6 29.0 32.6 37.2 42.5

80 11.0 13.5 16.8 19.5 22.5 27.5 30.1 34.9 39.1

90 8.95 11.2 13.9 16.7 19.6 23.0 26.2 29.6 33.7

95 6.95 10.5 12.2 15.6 18.1 20.9 24.8 28.3 30.5

98 6.18 9.18 11.3 13.9 17.5 20.3 23.0 27.4 27.9

99 5.87 8.93 11.0 13.1 17.0 19.4 22.1 26.8 27.6
164 Methods for Estimating Selected Low-Flow Statistics and Development of Annual Flow-Duration Statistics for Ohio

04191500 Auglaize River near Defiance, Ohio

Years analyzed = 92

Climatic year range = 1917–2008

[APEE, annual percentage equaled or exceeded; ft3/s, cubic foot per second]

Daily mean streamflow (ft3/s) that was equaled or exceeded the indicated percentage of time at APEE level

APEE 98 95 90 80 50 20 10 5 2

1 4370. 8250. 9420. 13000. 18800. 25200. 29500. 32600. 36600.

2 3390. 6430. 7650. 9750. 14500. 18700. 22800. 26200. 30500.

5 2270. 3330. 4190. 5850. 8940. 11700. 14400. 15700. 18400.

10 836. 1590. 2330. 2810. 5020. 7150. 8670. 10400. 12000.

20 365. 619. 896. 1180. 2160. 3410. 4410. 4960. 5760.

25 283. 448. 646. 836. 1550. 2680. 3290. 3540. 4560.

30 218. 301. 490. 611. 1190. 2020. 2570. 2690. 3480.

40 113. 137. 280. 352. 702. 1140. 1520. 1720. 2010.

50 42.9 73.6 129. 217. 477. 779. 982. 1180. 1380.

60 34.9 39.0 65.7 135. 292. 511. 662. 829. 1010.

70 30.0 33.8 50.0 75.9 185. 325. 448. 589. 717.

75 26.9 31.3 40.6 53.8 138. 231. 339. 512. 652.

80 24.9 30.0 32.8 40.6 93.1 191. 255. 460. 561.

90 8.30 20.0 25.0 31.6 49.0 99.6 163. 267. 387.

95 4.72 13.6 20.0 25.6 36.6 79.2 94.4 168. 292.

98 3.75 9.51 17.0 20.4 31.5 52.8 73.9 123. 167.

99 3.42 7.62 12.4 19.0 29.8 46.5 62.2 77.2 139.

7-day mean streamflow (ft3/s) that was equaled or exceeded the indicated percentage of time at APEE level

APEE 98 95 90 80 50 20 10 5 2

1 4160. 6210. 6940. 8430. 14300. 19300. 23300. 25500. 29500.

2 2990. 5510. 6250. 7300. 11300. 15500. 18400. 21300. 24100.

5 1760. 3430. 4300. 5360. 8320. 10900. 12400. 14200. 17000.

10 704. 1540. 2210. 3140. 5120. 7250. 8340. 9500. 10900.

20 318. 610. 960. 1400. 2580. 3950. 5030. 5830. 7090.

25 263. 474. 726. 976. 1840. 3050. 3860. 4860. 5320.

30 219. 315. 548. 718. 1420. 2370. 3200. 3810. 4280.

40 145. 156. 305. 387. 812. 1420. 2070. 2500. 3060.

50 90.4 100. 138. 237. 572. 935. 1300. 1570. 1960.

60 56.8 71.0 87.1 165. 334. 595. 820. 1080. 1300.

70 43.2 51.8 61.5 112. 209. 392. 538. 736. 917.

75 38.1 41.3 56.7 91.5 169. 285. 463. 613. 797.

80 35.4 37.0 52.8 76.3 133. 220. 340. 567. 684.

90 11.3 26.0 33.3 46.7 80.8 132. 194. 324. 492.

95 5.31 19.4 27.5 34.8 65.0 99.0 152. 220. 392.

98 4.61 13.4 21.9 27.9 47.1 79.9 106. 191. 298.

99 3.62 11.7 19.7 24.4 42.4 70.2 92.4 166. 270.
Appendix 5 165

04192500 Maumee River near Defiance, Ohio

Years analyzed = 75

Climatic year range = 1925–2008

[APEE, annual percentage equaled or exceeded; ft3/s, cubic foot per second]

Daily mean streamflow (ft3/s) that was equaled or exceeded the indicated percentage of time at APEE level

APEE 98 95 90 80 50 20 10 5 2

1 12700. 15800. 20900. 25800. 35900. 47700. 57300. 61100. 69800.

2 9730. 12900. 16800. 19500. 29600. 37500. 41200. 47400. 59700.

5 4880. 8060. 10300. 13000. 20100. 25800. 29600. 33300. 37500.

10 2680. 3880. 5680. 7550. 12200. 17800. 21000. 22300. 24800.

20 1040. 1800. 2670. 3420. 6440. 9580. 11700. 13200. 13500.

25 779. 1250. 2090. 2530. 5040. 7580. 9160. 10400. 11200.

30 588. 813. 1550. 1920. 3660. 6070. 7340. 8200. 9080.

40 449. 485. 814. 1260. 2360. 3680. 4680. 5180. 6310.

50 269. 312. 457. 746. 1560. 2490. 3190. 3620. 4150.

60 191. 238. 297. 514. 1070. 1650. 2250. 2570. 2890.

70 142. 192. 240. 347. 700. 1180. 1590. 2060. 2080.

75 126. 175. 220. 305. 600. 911. 1400. 1720. 1880.

80 114. 135. 190. 251. 474. 716. 1230. 1380. 1540.

90 68.9 94.4 128. 172. 302. 467. 781. 931. 1070.

95 54.4 68.0 97.1 135. 255. 367. 529. 709. 764.

98 30.1 56.4 76.6 103. 208. 313. 426. 558. 652.

99 16.7 49.8 71.1 90.4 180. 290. 376. 505. 560.

7-day mean streamflow (ft3/s) that was equaled or exceeded the indicated percentage of time at APEE level

APEE 98 95 90 80 50 20 10 5 2

1 10400. 13700. 16100. 19300. 26800. 38800. 49200. 52300. 61100.

2 8340. 9970. 14800. 16800. 23900. 30900. 36200. 39900. 49900.

5 4370. 7970. 10200. 12100. 18000. 23400. 25900. 29200. 35500.

10 2400. 3370. 5530. 7390. 11900. 16700. 19800. 20600. 23600.

20 979. 1870. 3070. 3840. 7110. 10700. 12400. 13600. 15000.

25 733. 1280. 2260. 2850. 5620. 8820. 10100. 11200. 12700.

30 563. 831. 1660. 2080. 4320. 6700. 8210. 9530. 10700.

40 442. 477. 889. 1300. 2760. 4360. 5580. 6440. 7030.

50 280. 324. 473. 804. 1810. 2880. 3810. 4580. 5260.

60 193. 246. 303. 544. 1210. 1940. 2720. 3160. 3600.

70 155. 204. 250. 380. 757. 1290. 1870. 2270. 2510.

75 138. 190. 222. 317. 647. 1040. 1630. 2050. 2190.

80 119. 170. 204. 280. 508. 802. 1420. 1630. 1860.

90 77.1 103. 139. 193. 316. 511. 878. 1070. 1300.

95 66.2 71.2 98.8 150. 268. 418. 628. 837. 981.

98 49.6 62.9 83.8 119. 232. 360. 492. 696. 773.

99 37.9 59.5 75.2 110. 216. 319. 433. 614. 706.
166 Methods for Estimating Selected Low-Flow Statistics and Development of Annual Flow-Duration Statistics for Ohio

04193500 Maumee River at Waterville, Ohio

Years analyzed = 85

Climatic year range = 1899–2008

[APEE, annual percentage equaled or exceeded; ft3/s, cubic foot per second]

Daily mean streamflow (ft3/s) that was equaled or exceeded the indicated percentage of time at APEE level

APEE 98 95 90 80 50 20 10 5 2

1 16900. 19100. 23000. 29100. 40800. 54600. 64900. 67500. 77400.

2 12400. 15900. 18300. 22000. 32900. 44000. 47400. 54500. 67300.

5 6420. 9380. 11800. 15000. 22400. 29400. 32800. 36200. 44500.

10 3030. 5380. 6880. 9030. 14000. 19700. 22400. 24100. 28100.

20 1340. 2400. 3130. 4390. 7280. 10900. 13300. 15000. 15600.

25 986. 1610. 2430. 2980. 5560. 8090. 10800. 11700. 12800.

30 722. 1060. 1790. 2300. 4210. 6280. 8270. 9410. 10300.

40 475. 573. 922. 1410. 2600. 3870. 5420. 5830. 6480.

50 322. 363. 505. 850. 1780. 2690. 3680. 4000. 4630.

60 256. 268. 322. 490. 1170. 1900. 2560. 2920. 3460.

70 108. 170. 225. 308. 780. 1280. 1850. 2150. 2460.

75 86.4 106. 196. 264. 616. 990. 1530. 1850. 2110.

80 74.3 78.0 142. 229. 469. 779. 1250. 1660. 1870.

90 25.8 62.0 91.4 159. 310. 507. 807. 1050. 1320.

95 15.8 57.5 70.0 121. 238. 408. 587. 787. 982.

98 8.60 50.6 62.5 91.2 186. 346. 461. 639. 743.

99 5.00 36.9 50.0 78.2 163. 321. 417. 573. 641.

7-day mean streamflow (ft3/s) that was equaled or exceeded the indicated percentage of time at APEE level

APEE 98 95 90 80 50 20 10 5 2

1 13300. 15300. 18700. 22400. 32300. 44800. 54600. 59000. 70600.

2 11000. 12400. 16200. 19100. 26700. 35200. 39800. 47100. 57500.

5 5950. 9980. 11200. 14400. 20000. 26400. 29000. 33000. 40000.

10 2830. 5000. 6840. 8730. 13800. 18200. 22000. 22800. 25500.

20 1290. 2400. 3470. 4750. 8080. 11200. 13700. 15300. 17300.

25 925. 1690. 2590. 3530. 6200. 9480. 11300. 12500. 14600.

30 661. 1040. 1990. 2450. 4690. 7390. 9580. 10300. 12100.

40 466. 571. 961. 1530. 2980. 4600. 6520. 7300. 7690.

50 338. 381. 519. 862. 2040. 3190. 4410. 4950. 5380.

60 266. 291. 333. 511. 1230. 2300. 2970. 3360. 3970.

70 134. 190. 239. 373. 855. 1430. 2160. 2570. 2770.

75 92.2 130. 202. 280. 688. 1140. 1860. 2040. 2500.

80 78.3 92.5 172. 242. 526. 867. 1560. 1770. 2230.

90 36.9 67.3 103. 183. 338. 534. 890. 1300. 1540.

95 25.9 58.7 85.1 138. 264. 454. 722. 898. 1220.

98 17.9 57.3 70.6 112. 225. 389. 499. 718. 1020.

99 15.8 55.3 66.7 108. 199. 359. 477. 661. 892.
Appendix 5 167

04195500 Portage River at Woodville, Ohio

Years analyzed = 57

Climatic year range = 1952–2008

[APEE, annual percentage equaled or exceeded; ft3/s, cubic foot per second]

Daily mean streamflow (ft3/s) that was equaled or exceeded the indicated percentage of time at APEE level

APEE 98 95 90 80 50 20 10 5 2

1 1500. 1570. 2120. 2650. 4200. 5450. 6910. 7830. 8210.

2 817. 1190. 1380. 1930. 3190. 3980. 4700. 5420. 6380.

5 437. 673. 918. 1020. 1740. 2410. 2950. 3300. 4340.

10 148. 277. 400. 489. 879. 1300. 1600. 2040. 2200.

20 57.1 125. 156. 221. 372. 586. 730. 926. 1050.

25 39.3 91.9 110. 158. 270. 430. 539. 685. 725.

30 32.8 62.7 79.8 118. 203. 318. 403. 537. 612.

40 21.2 31.5 44.7 72.6 122. 202. 251. 335. 382.

50 12.3 14.9 20.4 44.4 83.0 128. 176. 234. 265.

60 8.24 10.0 13.1 27.8 51.8 86.6 118. 162. 170.

70 6.28 7.68 10.8 19.2 34.0 54.5 79.0 118. 123.

75 5.56 6.99 9.74 15.0 24.0 44.2 67.2 100. 105.

80 4.79 6.30 9.42 12.6 20.0 36.4 58.7 87.5 91.7

90 3.32 4.68 7.03 9.00 12.0 23.6 38.1 51.5 62.1

95 2.96 3.66 4.90 6.98 9.77 17.4 22.8 35.5 42.7

98 2.39 2.68 4.31 5.80 8.00 12.1 18.0 24.4 30.3

99 2.13 2.48 4.00 5.32 7.37 11.0 15.1 20.4 26.8

7-day mean streamflow (ft3/s) that was equaled or exceeded the indicated percentage of time at APEE level

APEE 98 95 90 80 50 20 10 5 2

1 871. 952. 1240. 1780. 2660. 4020. 4960. 5610. 6000.

2 635. 786. 1050. 1340. 2160. 3080. 3450. 3730. 4790.

5 430. 626. 693. 1000. 1530. 2120. 2450. 2690. 3190.

10 160. 293. 423. 602. 999. 1360. 1790. 1930. 2470.

20 53.4 137. 158. 295. 499. 771. 1050. 1250. 1330.

25 38.2 105. 128. 183. 366. 598. 785. 982. 1060.

30 34.5 81.7 90.1 132. 267. 451. 617. 752. 821.

40 23.1 32.4 49.5 76.6 153. 295. 346. 487. 580.

50 14.2 17.1 20.7 47.0 102. 178. 238. 335. 369.

60 8.47 10.3 14.5 30.1 61.4 107. 164. 232. 248.

70 6.56 8.04 11.0 20.7 38.4 64.1 106. 167. 173.

75 6.01 7.22 10.4 16.9 28.7 50.2 81.1 140. 144.

80 5.03 6.47 9.78 14.3 20.9 38.7 69.6 106. 115.

90 3.55 5.03 7.72 9.55 13.2 26.6 48.9 83.3 84.4

95 3.02 3.84 5.52 7.84 11.0 20.3 28.3 54.3 66.2

98 2.64 2.95 4.75 6.65 9.13 13.6 21.4 28.9 45.6

99 2.39 2.62 4.46 6.15 8.19 12.5 17.3 25.8 38.2
168 Methods for Estimating Selected Low-Flow Statistics and Development of Annual Flow-Duration Statistics for Ohio

04196000 Sandusky River near Bucyrus, Ohio

Years analyzed = 51

Climatic year range = 1926–2008

[APEE, annual percentage equaled or exceeded; ft3/s, cubic foot per second]

Daily mean streamflow (ft3/s) that was equaled or exceeded the indicated percentage of time at APEE level

APEE 98 95 90 80 50 20 10 5 2

1 252. 466. 677. 796. 1240. 1530. 1750. 1920. 2460.

2 148. 307. 405. 493. 850. 1130. 1290. 1480. 1730.

5 77.6 131. 203. 243. 406. 583. 697. 843. 935.

10 46.3 70.2 92.8 130. 200. 292. 348. 383. 459.

20 15.4 31.2 43.9 56.8 90.0 143. 163. 168. 195.

25 8.78 21.8 30.8 44.0 69.0 111. 119. 126. 134.

30 4.63 15.7 24.2 33.4 55.0 85.6 98.8 106. 117.

40 2.35 8.80 12.4 20.2 35.0 55.4 69.4 73.4 81.9

50 1.62 4.52 7.89 14.0 24.0 38.8 47.8 52.2 53.0

60 1.27 2.94 4.61 9.32 16.4 25.6 33.2 38.8 41.9

70 1.13 2.14 3.64 5.57 10.0 16.5 20.6 27.4 33.8

75 1.12 1.88 3.16 4.68 8.65 13.8 17.6 24.0 28.8

80 1.12 1.74 2.80 3.84 7.40 11.0 13.0 17.9 25.7

90 1.02 1.46 2.02 2.70 4.50 7.27 8.96 10.7 14.9

95 0.90 1.12 1.53 2.12 3.47 5.47 6.83 8.76 11.0

98 0.80 0.98 1.20 1.68 2.80 4.56 5.13 7.05 8.19

99 0.67 0.79 0.94 1.43 2.60 4.12 4.59 5.65 6.86

7-day mean streamflow (ft3/s) that was equaled or exceeded the indicated percentage of time at APEE level

APEE 98 95 90 80 50 20 10 5 2

1 128. 296. 398. 461. 642. 841. 943. 1200. 1980.

2 98.6 222. 324. 377. 562. 704. 893. 1010. 1100.

5 81.2 141. 222. 280. 398. 512. 595. 749. 941.

10 57.6 89.0 125. 161. 254. 336. 397. 433. 592.

20 19.5 31.6 59.3 83.4 120. 188. 246. 269. 311.

25 7.96 23.8 39.3 62.1 90.6 162. 195. 221. 228.

30 4.14 18.7 28.4 43.4 73.1 131. 155. 173. 190.

40 2.72 9.42 14.8 22.1 45.7 79.5 99.0 114. 137.

50 1.99 5.09 9.33 15.5 30.4 53.5 62.7 71.3 80.0

60 1.62 3.36 5.41 9.48 20.1 33.5 42.0 47.5 57.1

70 1.37 2.67 3.71 6.47 12.5 20.7 27.2 34.7 40.7

75 1.24 2.26 3.44 5.65 9.79 16.6 20.2 30.9 37.0

80 1.19 1.97 3.06 4.84 8.39 13.7 15.7 26.8 32.6

90 1.09 1.67 2.22 3.35 5.26 9.18 10.5 14.4 20.5

95 1.03 1.26 1.71 2.55 4.42 7.20 7.80 10.3 12.8

98 0.95 1.17 1.41 2.06 4.01 5.83 6.59 8.65 11.0

99 0.93 1.13 1.26 1.82 3.39 5.08 5.92 7.69 9.88
Appendix 5 169

04196800 Tymochtee Creek at Crawford, Ohio

Years analyzed = 36

Climatic year range = 1973–2008

[APEE, annual percentage equaled or exceeded; ft3/s, cubic foot per second]

Daily mean streamflow (ft3/s) that was equaled or exceeded the indicated percentage of time at APEE level

APEE 95 90 80 70 50 30 20 10 5

1 688. 833. 1390. 1860. 2120. 2600. 3140. 3870. 4330.

2 435. 641. 1060. 1380. 1660. 1950. 2220. 2930. 3520.

5 236. 361. 652. 811. 1010. 1310. 1450. 1790. 2350.

10 114. 164. 308. 373. 521. 773. 953. 1110. 1140.

20 44.6 59.8 102. 154. 199. 318. 424. 468. 494.

25 30.3 41.8 70.1 112. 148. 206. 302. 329. 345.

30 21.9 28.1 53.6 80.2 111. 156. 216. 244. 264.

40 9.10 14.4 31.5 40.8 64.0 90.0 136. 152. 161.

50 4.46 9.16 19.4 25.1 40.3 57.3 81.6 100. 109.

60 2.75 5.02 9.20 13.1 22.5 36.8 50.2 68.0 76.2

70 1.29 2.20 4.09 5.40 13.8 20.9 31.6 47.9 53.9

75 0.84 1.91 2.68 3.56 9.90 17.9 25.9 39.8 44.6

80 0.56 1.38 1.70 2.44 6.70 16.7 20.1 32.3 34.5

90 0.21 0.41 0.73 1.33 3.09 8.04 10.6 19.5 20.9

95 0.08 0.13 0.42 0.51 1.70 5.77 7.35 10.1 15.4

98 0.02 0.08 0.19 0.35 1.10 3.73 5.25 6.74 11.3

99 0.02 0.04 0.14 0.26 0.82 3.18 4.25 5.88 9.61

7-day mean streamflow (ft3/s) that was equaled or exceeded the indicated percentage of time at APEE level

APEE 95 90 80 70 50 30 20 10 5

1 433. 630. 901. 1220. 1530. 1850. 2100. 2630. 3070.

2 332. 566. 781. 953. 1200. 1510. 1800. 2220. 2380.

5 224. 364. 602. 772. 901. 1090. 1320. 1620. 1890.

10 138. 170. 345. 459. 560. 723. 855. 1020. 1350.

20 53.7 76.4 134. 199. 292. 419. 546. 577. 731.

25 33.0 49.2 86.3 152. 199. 296. 408. 466. 563.

30 24.5 31.8 63.0 109. 154. 216. 313. 376. 461.

40 12.0 17.3 36.3 52.7 91.4 127. 177. 218. 243.

50 4.89 9.54 20.8 27.9 51.6 77.0 112. 142. 161.

60 2.97 5.41 9.46 14.8 27.9 50.5 64.0 95.8 103.

70 1.66 2.41 3.93 5.55 15.3 29.5 43.4 66.4 75.0

75 0.92 1.79 2.92 3.67 11.9 21.4 37.5 54.5 61.5

80 0.62 1.45 1.79 2.72 7.34 19.3 27.0 42.8 47.8

90 0.31 0.50 0.80 1.48 3.02 9.38 12.5 25.0 25.9

95 0.11 0.16 0.47 0.58 2.02 6.45 8.80 16.1 16.9

98 0.05 0.10 0.25 0.44 1.28 4.74 6.65 10.3 11.6

99 0.04 0.08 0.20 0.35 1.08 4.23 5.01 8.23 10.4
170 Methods for Estimating Selected Low-Flow Statistics and Development of Annual Flow-Duration Statistics for Ohio

04200500 Black River at Elyria, Ohio

Years analyzed = 64

Climatic year range = 1945–2008

[APEE, annual percentage equaled or exceeded; ft3/s, cubic foot per second]

Daily mean streamflow (ft3/s) that was equaled or exceeded the indicated percentage of time at APEE level

APEE 98 95 90 80 50 20 10 5 2

1 1410. 1760. 2340. 3240. 4450. 5550. 6810. 7590. 8770.

2 994. 1240. 1640. 2200. 2920. 4030. 4510. 5570. 6940.

5 421. 681. 839. 1020. 1480. 2260. 2570. 3160. 3630.

10 223. 283. 399. 512. 767. 1290. 1490. 1590. 1930.

20 69.3 138. 164. 214. 359. 594. 687. 762. 841.

25 48.5 97.1 118. 149. 271. 419. 536. 592. 648.

30 36.6 71.2 87.8 109. 212. 317. 415. 493. 510.

40 24.9 38.6 46.5 64.2 134. 208. 259. 319. 347.

50 18.3 19.5 30.0 40.0 87.0 130. 172. 226. 254.

60 11.9 14.1 20.0 27.4 56.5 93.0 121. 162. 170.

70 8.69 11.0 13.9 19.0 33.5 58.0 76.4 101. 124.

75 7.46 9.08 11.5 16.0 25.3 46.0 62.3 77.0 93.3

80 6.04 7.57 10.2 13.0 20.1 36.2 46.2 63.8 69.4

90 3.83 5.62 7.10 8.46 13.0 22.0 25.9 32.2 42.4

95 2.57 4.43 5.45 6.50 9.68 17.0 20.0 23.7 29.2

98 1.94 3.48 4.25 5.10 7.87 12.3 16.2 17.2 21.4

99 1.65 3.05 3.83 4.70 6.85 12.0 14.2 14.7 18.5

7-day mean streamflow (ft3/s) that was equaled or exceeded the indicated percentage of time at APEE level

APEE 98 95 90 80 50 20 10 5 2

1 906. 1110. 1560. 1740. 2710. 3580. 4040. 4510. 5540.

2 834. 891. 1190. 1490. 2070. 2860. 3300. 3920. 4330.

5 431. 587. 801. 1080. 1440. 1880. 2430. 2780. 3390.

10 268. 350. 427. 614. 906. 1370. 1510. 1840. 2150.

20 70.2 158. 215. 284. 472. 810. 966. 1060. 1180.

25 54.3 110. 135. 208. 366. 641. 761. 847. 928.

30 38.0 88.0 101. 146. 280. 493. 591. 654. 771.

40 26.0 41.5 51.1 73.0 173. 312. 353. 452. 517.

50 18.2 21.0 30.7 46.0 109. 194. 249. 328. 377.

60 12.1 15.1 21.8 32.0 63.9 115. 167. 215. 253.

70 9.00 12.0 15.3 21.7 40.9 68.0 109. 151. 160.

75 6.90 9.89 11.9 17.6 31.2 53.0 86.6 104. 135.

80 6.22 8.44 10.7 14.6 24.0 41.4 62.9 82.3 99.3

90 3.78 6.19 7.78 9.44 13.7 26.6 31.4 45.7 51.3

95 3.00 4.82 6.12 7.43 10.5 19.4 25.0 30.3 37.7

98 2.58 4.33 4.99 6.20 9.35 16.4 19.7 23.2 30.3

99 2.47 4.13 4.66 5.80 8.79 14.1 17.3 20.4 23.2
Appendix 5 171

04201500 Rocky River near Berea, Ohio

Years analyzed = 76

Climatic year range = 1924–2008

[APEE, annual percentage equaled or exceeded; ft3/s, cubic foot per second]

Daily mean streamflow (ft3/s) that was equaled or exceeded the indicated percentage of time at APEE level

APEE 98 95 90 80 50 20 10 5 2

1 1050. 1730. 1960. 2390. 3390. 4670. 5180. 5630. 6620.

2 811. 1070. 1350. 1690. 2400. 3200. 3610. 4100. 4350.

5 339. 452. 783. 908. 1220. 1790. 2000. 2190. 2540.

10 205. 258. 354. 456. 668. 945. 1190. 1230. 1460.

20 71.5 101. 155. 213. 315. 462. 580. 619. 719.

25 48.4 74.0 121. 152. 253. 377. 443. 473. 555.

30 34.6 56.4 88.4 124. 208. 308. 362. 392. 453.

40 20.2 29.1 49.1 81.7 136. 208. 244. 278. 315.

50 14.4 19.4 25.0 52.0 92.8 151. 186. 218. 239.

60 8.97 11.7 17.0 33.4 60.5 109. 147. 163. 176.

70 5.28 7.90 11.9 19.4 43.9 75.6 102. 118. 130.

75 3.84 6.36 9.15 14.7 37.0 65.7 82.8 104. 108.

80 2.85 4.93 6.42 12.4 32.0 54.4 67.8 77.9 93.6

90 1.09 2.36 3.98 7.34 20.3 36.2 42.0 54.3 59.3

95 0.55 1.91 3.22 5.70 15.3 29.0 35.0 40.7 46.7

98 0.41 1.32 2.45 4.06 10.7 23.7 29.5 32.7 35.5

99 0.39 0.80 2.34 3.69 9.20 22.6 27.1 28.7 30.3

7-day mean streamflow (ft3/s) that was equaled or exceeded the indicated percentage of time at APEE level

APEE 98 95 90 80 50 20 10 5 2

1 616. 933. 1160. 1290. 1920. 2490. 2800. 2990. 3330.

2 537. 720. 914. 1110. 1530. 2180. 2410. 2610. 3090.

5 371. 561. 737. 817. 1080. 1440. 1630. 1980. 2290.

10 224. 305. 432. 543. 766. 1050. 1200. 1310. 1530.

20 77.1 141. 201. 279. 429. 694. 771. 879. 938.

25 51.0 88.8 156. 196. 334. 538. 651. 706. 805.

30 35.0 65.0 109. 151. 258. 445. 545. 597. 683.

40 21.7 29.8 54.4 97.5 164. 291. 361. 431. 491.

50 14.7 19.8 30.5 57.8 119. 192. 259. 309. 366.

60 9.12 11.8 18.8 36.4 76.1 133. 180. 237. 278.

70 4.96 8.11 12.1 20.9 53.3 97.8 140. 153. 179.

75 4.09 7.01 9.57 16.8 47.1 83.0 109. 132. 159.

80 3.16 5.40 6.97 13.6 39.4 69.7 84.0 104. 133.

90 1.52 3.64 4.54 8.71 25.5 44.7 55.9 76.1 88.3

95 0.74 2.49 3.59 7.00 17.9 33.5 42.1 50.8 58.1

98 0.49 1.95 2.85 4.99 13.9 28.5 34.6 39.3 44.5

99 0.40 1.55 2.50 4.05 11.4 26.4 31.6 36.1 39.7
172 Methods for Estimating Selected Low-Flow Statistics and Development of Annual Flow-Duration Statistics for Ohio

04208000 Cuyahoga River at Independence, Ohio

Years analyzed = 77

Climatic year range = 1922–2008

[APEE, annual percentage equaled or exceeded; ft3/s, cubic foot per second]

Daily mean streamflow (ft3/s) that was equaled or exceeded the indicated percentage of time at APEE level

APEE 98 95 90 80 50 20 10 5 2

1 2270. 3090. 3400. 3860. 5340. 6490. 7210. 8010. 9520.

2 1830. 2250. 2830. 3060. 4200. 5180. 5790. 6150. 7150.

5 1250. 1550. 1870. 2180. 2770. 3550. 3970. 4180. 4690.

10 881. 1090. 1180. 1500. 1960. 2710. 2960. 3150. 3280.

20 487. 576. 728. 891. 1250. 1690. 1950. 2110. 2210.

25 356. 429. 579. 730. 1040. 1420. 1640. 1780. 1860.

30 282. 328. 481. 591. 898. 1230. 1380. 1600. 1610.

40 193. 225. 297. 392. 647. 930. 1090. 1230. 1300.

50 146. 158. 230. 256. 486. 719. 880. 1030. 1070.

60 108. 113. 167. 212. 381. 552. 729. 850. 882.

70 86.4 95.6 129. 174. 301. 444. 554. 635. 715.

75 79.4 91.0 118. 155. 257. 406. 484. 564. 637.

80 69.9 83.0 111. 141. 232. 367. 424. 474. 569.

90 55.0 65.8 84.2 114. 188. 277. 328. 362. 409.

95 45.9 52.1 73.6 101. 157. 238. 281. 308. 344.

98 36.6 45.3 68.3 93.6 141. 218. 241. 281. 303.

99 30.7 39.0 64.8 87.1 135. 205. 233. 264. 292.

7-day mean streamflow (ft3/s) that was equaled or exceeded the indicated percentage of time at APEE level

APEE 98 95 90 80 50 20 10 5 2

1 1680. 2210. 2410. 2780. 3960. 4800. 5370. 5800. 6900.

2 1490. 1970. 2000. 2510. 3430. 4100. 4510. 4750. 6290.

5 1190. 1510. 1660. 1970. 2480. 3280. 3600. 3840. 4840.

10 842. 1060. 1150. 1530. 1920. 2550. 2750. 2840. 3030.

20 449. 533. 773. 885. 1300. 1830. 2030. 2180. 2330.

25 334. 435. 586. 760. 1110. 1530. 1750. 1970. 2060.

30 266. 306. 483. 636. 956. 1320. 1560. 1780. 1860.

40 197. 221. 332. 419. 696. 994. 1230. 1410. 1470.

50 157. 162. 230. 274. 521. 783. 972. 1180. 1220.

60 107. 115. 185. 221. 411. 621. 818. 972. 1030.

70 83.1 99.9 141. 182. 325. 518. 618. 713. 829.

75 78.1 92.7 127. 157. 292. 449. 530. 626. 755.

80 73.4 88.2 119. 149. 270. 410. 498. 554. 672.

90 62.9 76.0 99.0 125. 208. 321. 379. 422. 503.

95 55.9 62.9 89.6 111. 180. 269. 325. 371. 388.

98 48.9 59.5 86.4 99.6 149. 241. 288. 324. 347.

99 44.8 57.6 82.3 97.8 148. 231. 275. 298. 327.
Appendix 5 173

04209000 Chagrin River at Willoughby, Ohio

Years analyzed = 69

Climatic year range = 1926–2008

[APEE, annual percentage equaled or exceeded; ft3/s, cubic foot per second]

Daily mean streamflow (ft3/s) that was equaled or exceeded the indicated percentage of time at APEE level

APEE 98 95 90 80 50 20 10 5 2

1 1520. 2010. 2100. 2430. 3380. 4120. 4610. 5220. 7020.

2 1070. 1380. 1530. 1760. 2270. 2870. 3340. 4280. 5100.

5 564. 671. 893. 1000. 1340. 1690. 1940. 2040. 2910.

10 367. 394. 484. 594. 795. 1020. 1080. 1450. 2130.

20 194. 213. 284. 323. 438. 580. 638. 747. 1010.

25 155. 172. 218. 253. 339. 470. 520. 578. 748.

30 124. 147. 162. 207. 286. 396. 432. 463. 584.

40 79.4 103. 110. 143. 214. 284. 319. 347. 389.

50 55.0 66.0 80.0 99.0 160. 220. 241. 265. 279.

60 40.6 51.0 56.0 71.0 118. 162. 188. 202. 221.

70 30.3 36.0 39.0 52.2 80.8 124. 147. 155. 171.

75 26.6 29.5 35.0 44.0 70.0 109. 126. 135. 144.

80 22.8 26.0 31.0 37.0 58.0 97.0 108. 115. 120.

90 14.6 19.0 22.0 27.0 44.0 72.6 83.0 89.0 98.0

95 10.2 14.7 18.3 25.0 35.0 59.0 68.0 75.2 84.4

98 7.24 12.2 16.0 20.3 28.0 52.3 61.0 66.8 73.6

99 5.85 8.32 14.0 18.7 27.0 47.0 58.0 64.8 70.4

7-day mean streamflow (ft3/s) that was equaled or exceeded the indicated percentage of time at APEE level

APEE 98 95 90 80 50 20 10 5 2

1 865. 1050. 1240. 1510. 1890. 2550. 2990. 3180. 3700.

2 698. 876. 998. 1210. 1610. 1930. 2140. 2390. 3340.

5 567. 687. 799. 924. 1200. 1480. 1540. 1670. 2680.

10 394. 451. 496. 636. 842. 1080. 1230. 1370. 1960.

20 213. 245. 314. 390. 534. 733. 792. 893. 1110.

25 173. 198. 274. 314. 440. 624. 677. 767. 964.

30 141. 155. 193. 251. 362. 498. 568. 664. 830.

40 85.1 112. 129. 161. 266. 350. 425. 481. 587.

50 60.3 75.4 83.6 113. 185. 261. 308. 360. 440.

60 39.3 51.1 57.3 78.6 131. 204. 238. 278. 339.

70 31.1 36.0 41.0 54.1 94.6 146. 182. 200. 239.

75 27.9 31.6 39.3 47.1 81.6 130. 155. 172. 207.

80 25.2 27.7 31.3 39.1 68.1 119. 135. 154. 164.

90 17.8 21.3 24.2 29.7 51.4 84.1 94.1 106. 113.

95 12.2 16.0 21.0 26.4 37.0 64.4 78.9 88.6 100.

98 9.30 12.8 17.4 23.4 32.7 56.0 69.6 80.7 90.0

99 7.65 11.8 15.9 21.4 29.6 53.9 65.3 77.2 83.3
174 Methods for Estimating Selected Low-Flow Statistics and Development of Annual Flow-Duration Statistics for Ohio

04211500 Mill Creek near Jefferson, Ohio

Years analyzed = 32

Climatic year range = 1942–73

[APEE, annual percentage equaled or exceeded; ft3/s, cubic foot per second]

Daily mean streamflow (ft3/s) that was equaled or exceeded the indicated percentage of time at APEE level

APEE 95 90 80 70 50 30 20 10 5

1 760. 885. 1040. 1140. 1290. 1430. 1700. 2050. 2380.

2 539. 622. 736. 877. 959. 1090. 1130. 1270. 1350.

5 245. 295. 401. 472. 558. 633. 661. 747. 769.

10 133. 156. 199. 224. 291. 339. 365. 393. 428.

20 62.9 71.4 85.2 93.0 127. 156. 183. 202. 206.

25 38.3 50.0 62.7 71.0 86.8 107. 130. 152. 158.

30 25.6 35.6 44.5 51.5 62.6 80.5 93.5 115. 123.

40 12.5 17.4 22.0 26.0 33.8 46.5 55.5 72.8 78.1

50 3.45 5.45 7.08 9.14 16.8 26.6 35.4 46.8 49.0

60 0.10 0.26 1.14 2.59 6.24 13.1 21.4 28.6 31.1

70 0.00 0.02 0.10 0.10 1.93 5.32 8.02 16.0 18.4

75 0.00 0.00 0.00 0.10 1.09 2.68 4.14 9.89 12.0

80 0.00 0.00 0.00 0.10 0.40 1.34 2.48 4.58 6.96

90 0.00 0.00 0.00 0.00 0.10 0.21 0.42 0.87 2.33

95 0.00 0.00 0.00 0.00 0.05 0.10 0.10 0.27 1.11

98 0.00 0.00 0.00 0.00 0.03 0.10 0.10 0.10 0.50

99 0.00 0.00 0.00 0.00 0.03 0.10 0.10 0.10 0.38

7-day mean streamflow (ft3/s) that was equaled or exceeded the indicated percentage of time at APEE level

APEE 95 90 80 70 50 30 20 10 5

1 358. 518. 607. 683. 795. 982. 1010. 1110. 1170.

2 306. 441. 498. 528. 614. 726. 785. 872. 973.

5 218. 274. 356. 427. 455. 525. 553. 607. 652.

10 141. 162. 250. 281. 339. 356. 386. 436. 456.

20 72.6 84.0 134. 163. 186. 210. 233. 268. 306.

25 56.7 65.4 95.0 112. 149. 170. 196. 221. 242.

30 34.0 47.7 67.8 78.7 108. 136. 157. 177. 194.

40 13.4 25.1 31.4 38.9 53.4 76.3 89.1 115. 132.

50 4.31 5.92 9.72 13.1 23.5 34.3 50.8 84.2 85.3

60 0.09 0.32 1.59 2.78 10.7 19.2 30.9 45.1 47.9

70 0.00 0.07 0.13 0.23 2.71 8.64 14.4 22.1 26.8

75 0.00 0.00 0.05 0.10 1.20 3.82 8.04 15.8 19.4

80 0.00 0.00 0.00 0.10 0.70 2.20 3.11 8.69 13.2

90 0.00 0.00 0.00 0.00 0.11 0.36 0.69 1.67 3.84

95 0.00 0.00 0.00 0.00 0.10 0.10 0.23 0.35 1.22

98 0.00 0.00 0.00 0.00 0.05 0.10 0.10 0.23 0.80

99 0.00 0.00 0.00 0.00 0.05 0.10 0.10 0.14 0.65
Appendix 6 175

Appendix 6. Annual Seasonal-Period Flow-Duration Results for Sites with 

Streamflows that are Subject to Regulation
176 Methods for Estimating Selected Low-Flow Statistics and Development of Annual Flow-Duration Statistics for Ohio

03086500 Mahoning River at Alliance, Ohio

Years analyzed = 38

Climatic year range = 1955–92

[APEE, annual percentage equaled or exceeded; ft3/s, cubic foot per second; Sep, September; Nov, November]

Sep–Nov daily mean streamflow (ft3/s) that was equaled or exceeded the indicated percentage of time at APEE level

APEE 95 90 80 70 50 30 20 10 5

1 10.0 26.7 64.8 86.5 223. 373. 508. 711. 799.

2 9.82 24.3 55.9 70.8 174. 329. 423. 580. 719.

5 9.01 23.0 40.1 48.7 107. 188. 303. 423. 530.

10 8.34 19.2 29.4 38.8 57.2 123. 183. 312. 328.

20 6.95 16.0 20.6 25.8 35.7 76.0 121. 141. 184.

25 6.93 11.9 16.8 23.4 31.3 61.9 98.6 117. 126.

30 6.92 9.96 16.0 21.0 29.1 47.0 77.1 97.9 109.

40 6.87 8.85 14.2 17.7 24.8 38.0 60.6 72.1 81.7

50 5.32 7.22 9.16 14.7 20.5 30.5 41.9 52.8 57.6

60 4.18 5.51 8.30 10.7 17.0 25.4 29.8 41.0 54.4

70 3.52 4.73 7.24 9.14 13.3 21.6 26.0 32.7 49.2

75 3.52 4.10 6.36 7.93 11.5 18.9 24.0 30.3 46.3

80 2.76 3.63 5.36 7.14 9.81 15.9 21.2 28.5 46.1

90 0.00 1.95 3.63 4.99 6.96 12.7 15.2 20.1 34.7

95 0.00 1.26 3.22 4.37 6.01 11.0 12.6 16.2 25.7

98 0.00 0.90 2.86 3.59 5.50 8.78 12.2 13.2 25.6

99 0.00 0.90 2.70 3.47 4.90 8.78 12.0 13.0 25.5

03093000 Eagle Creek at Phalanx Station, Ohio

Years analyzed = 80

Climatic year range = 1926–2008

[APEE, annual percentage equaled or exceeded; ft3/s, cubic foot per second; Sep, September; Nov, November]

Sep–Nov daily mean streamflow (ft3/s) that was equaled or exceeded the indicated percentage of time at APEE level

APEE 98 95 90 80 50 20 10 5 2

1 20.6 30.1 42.0 89.6 331. 893. 1470. 2240. 3540.

2 20.6 30.0 38.0 72.3 268. 616. 1080. 1470. 2500.

5 18.0 21.9 30.2 46.1 122. 369. 546. 729. 1140.

10 14.9 20.1 23.1 34.7 78.0 222. 336. 496. 689.

20 12.6 18.0 19.1 26.4 46.5 113. 163. 219. 262.

25 12.6 15.1 18.0 24.0 40.0 93.6 128. 162. 227.

30 11.2 13.5 17.0 22.0 35.5 76.3 114. 147. 189.

40 9.76 12.1 15.0 18.0 29.3 53.4 83.9 104. 132.

50 8.81 9.34 13.0 16.0 23.0 43.2 59.7 87.6 112.

60 8.06 8.76 12.0 14.2 20.0 31.8 46.7 74.2 90.4

70 7.28 8.04 10.1 13.0 16.1 27.6 38.3 51.5 74.6

75 6.80 7.73 9.63 12.0 15.5 26.8 35.7 49.0 70.3

80 6.38 7.59 9.00 11.0 14.4 24.0 33.9 46.4 65.9

90 5.08 6.22 7.16 8.90 12.0 20.8 24.9 38.0 42.2

95 4.17 5.03 6.04 7.96 11.0 18.0 21.6 28.9 35.6

98 2.99 4.06 5.21 6.62 10.4 17.0 19.8 26.0 30.1

99 2.17 3.81 4.55 6.02 9.90 17.0 19.0 24.9 30.1
Appendix 6 177

03097500 Meander Creek at Mineral Ridge, Ohio

Years analyzed = 22

Climatic year range = 1929–50

[APEE, annual percentage equaled or exceeded; ft3/s, cubic foot per second; Sep, September; Nov, November]

Sep–Nov daily mean streamflow (ft3/s) that was equaled or exceeded the indicated percentage of time at APEE level

APEE 95 90 80 70 50 30 20 10 5

1 1.42 1.53 1.76 2.07 2.60 6.67 66.2 162. 412.

2 1.34 1.43 1.68 1.95 2.47 5.99 55.0 137. 370.

5 0.90 1.09 1.34 1.54 1.85 4.92 37.4 105. 261.

10 0.82 0.90 1.05 1.24 1.65 2.22 5.28 59.0 147.

20 0.70 0.73 0.80 0.98 1.43 1.88 2.54 19.8 28.1

25 0.70 0.70 0.80 0.89 1.40 1.82 2.48 10.6 15.4

30 0.61 0.70 0.80 0.80 1.20 1.81 2.44 8.55 11.6

40 0.60 0.60 0.70 0.70 1.06 1.62 2.28 5.47 8.28

50 0.50 0.53 0.66 0.70 0.95 1.60 1.82 4.76 6.41

60 0.48 0.49 0.56 0.69 0.84 1.39 1.64 3.79 5.08

70 0.40 0.43 0.56 0.60 0.70 1.32 1.54 2.75 4.66

75 0.40 0.40 0.50 0.60 0.70 1.21 1.54 2.44 4.33

80 0.32 0.40 0.46 0.50 0.65 1.20 1.48 2.37 3.96

90 0.22 0.31 0.37 0.40 0.65 1.10 1.26 1.99 2.98

95 0.12 0.27 0.30 0.40 0.50 0.96 1.26 1.92 2.60

98 0.10 0.16 0.30 0.38 0.50 0.78 1.13 1.81 2.49

99 0.10 0.13 0.30 0.30 0.50 0.70 1.04 1.81 2.49

03097550 Mahoning River at Ohio Edison P Plt at Niles, Ohio

Years analyzed = 22

Climatic year range = 1987–2008

[APEE, annual percentage equaled or exceeded; ft3/s, cubic foot per second; Sep, September; Nov, November]

Sep–Nov daily mean streamflow (ft3/s) that was equaled or exceeded the indicated percentage of time at APEE level

APEE 95 90 80 70 50 30 20 10 5

1 546. 701. 896. 987. 1320. 3370. 4230. 5330. 7350.

2 448. 568. 732. 817. 1190. 2850. 3980. 4540. 6460.

5 387. 455. 513. 589. 1020. 1990. 3240. 3920. 4310.

10 374. 403. 432. 504. 847. 1390. 2440. 2670. 3180.

20 338. 363. 380. 401. 665. 966. 1920. 2240. 2310.

25 329. 341. 363. 374. 583. 913. 1770. 2160. 2260.

30 321. 326. 346. 363. 497. 880. 1630. 1950. 2060.

40 292. 310. 328. 337. 444. 770. 1190. 1610. 1730.

50 247. 298. 306. 313. 407. 648. 970. 1300. 1350.

60 234. 264. 285. 292. 376. 565. 773. 1110. 1180.

70 222. 247. 262. 273. 330. 456. 628. 902. 1020.

75 216. 233. 250. 268. 320. 433. 573. 813. 941.

80 211. 228. 242. 258. 310. 390. 529. 722. 858.

90 201. 207. 224. 234. 284. 380. 438. 594. 658.

95 196. 201. 213. 227. 271. 344. 399. 454. 560.

98 189. 189. 205. 224. 254. 330. 378. 440. 551.

99 185. 187. 202. 219. 249. 329. 374. 433. 545.
178 Methods for Estimating Selected Low-Flow Statistics and Development of Annual Flow-Duration Statistics for Ohio

03116000 Tuscarawas River at Clinton, Ohio

Years analyzed = 39

Climatic year range = 1939–77

[APEE, annual percentage equaled or exceeded; ft3/s, cubic foot per second; Sep, September; Nov, November]

Sep–Nov daily mean streamflow (ft3/s) that was equaled or exceeded the indicated percentage of time at APEE level

APEE 95 90 80 70 50 30 20 10 5

1 61.0 73.0 134. 152. 200. 388. 600. 782. 1000.

2 59.3 66.5 115. 132. 187. 324. 491. 694. 899.

5 51.0 59.4 84.0 91.8 135. 209. 274. 409. 577.

10 49.0 56.0 71.6 75.0 102. 138. 175. 236. 316.

20 46.0 54.0 62.4 66.6 81.6 95.2 125. 163. 178.

25 44.0 53.0 57.0 65.0 75.0 86.0 117. 141. 159.

30 43.4 49.8 53.0 61.8 70.4 82.4 109. 130. 155.

40 43.0 46.0 52.4 58.0 66.0 77.0 90.2 118. 142.

50 42.0 44.0 49.0 55.0 63.0 75.0 80.0 100. 130.

60 41.0 42.0 47.8 52.0 59.0 70.8 74.0 85.0 118.

70 37.6 40.0 44.0 48.0 57.0 66.0 70.0 79.0 111.

75 37.0 40.0 43.0 47.0 57.0 64.0 69.0 77.0 85.0

80 35.8 39.0 42.0 47.0 56.0 64.0 67.0 76.0 82.4

90 33.0 38.0 39.4 41.2 52.0 61.2 66.0 71.2 73.2

95 31.6 34.0 37.0 40.0 50.6 59.6 63.0 70.0 73.0

98 28.7 34.0 36.0 37.0 47.5 56.8 60.0 69.5 72.0

99 27.0 32.0 35.0 37.0 46.0 56.0 60.0 67.0 72.0

03116200 Chippewa Creek at Easton, Ohio

Years analyzed = 21

Climatic year range = 1960–80

[APEE, annual percentage equaled or exceeded; ft3/s, cubic foot per second; Sep, September; Nov, November]

Sep–Nov daily mean streamflow (ft3/s) that was equaled or exceeded the indicated percentage of time at APEE level

APEE 95 90 80 70 50 30 20 10 5

1 24.4 38.2 78.8 115. 210. 535. 591. 1280. 3720.

2 21.7 33.8 62.8 102. 144. 356. 498. 1260. 2450.

5 14.4 18.0 40.6 53.5 82.8 211. 266. 883. 1000.

10 11.4 15.4 23.5 34.0 46.8 100. 180. 322. 854.

20 10.2 14.2 17.6 23.8 32.2 53.7 104. 132. 443.

25 9.76 13.2 16.2 21.2 30.0 44.4 81.4 110. 408.

30 9.76 13.2 15.0 19.4 26.0 41.4 69.2 103. 302.

40 9.30 12.0 13.0 14.6 22.2 31.3 54.1 82.8 214.

50 8.84 11.0 12.0 13.2 20.0 27.6 40.2 71.0 167.

60 8.32 9.52 10.8 12.6 17.8 25.6 33.5 56.6 116.

70 7.92 9.02 10.3 11.0 15.0 22.2 28.9 48.1 92.2

75 7.87 8.52 9.76 11.0 15.0 20.8 24.2 44.6 84.8

80 7.19 7.62 9.13 9.92 14.0 20.0 21.4 40.0 72.1

90 6.22 6.56 8.06 9.06 13.0 16.9 20.6 28.2 35.4

95 5.09 5.98 7.13 8.72 12.0 16.0 18.6 25.8 33.8

98 4.47 5.22 6.68 8.28 10.8 14.4 17.1 25.5 32.2

99 4.22 4.64 6.58 7.94 10.0 14.4 16.6 24.0 31.3
Appendix 6 179

03117000 Tuscarawas River at Massillon, Ohio

Years analyzed = 71

Climatic year range = 1938–2008

[APEE, annual percentage equaled or exceeded; ft3/s, cubic foot per second; Sep, September; Nov, November]

Sep–Nov daily mean streamflow (ft3/s) that was equaled or exceeded the indicated percentage of time at APEE level

APEE 98 95 90 80 50 20 10 5 2

1 124. 214. 300. 449. 958. 2290. 2880. 3540. 6600.

2 118. 159. 257. 354. 728. 1980. 2440. 3300. 6010.

5 103. 119. 198. 254. 453. 1180. 2010. 2660. 3970.

10 89.9 107. 149. 200. 317. 671. 1130. 1800. 2260.

20 86.0 99.6 134. 150. 215. 421. 572. 987. 1160.

25 83.9 98.4 127. 142. 190. 359. 484. 704. 991.

30 82.5 96.2 113. 132. 176. 323. 432. 589. 854.

40 78.8 93.4 105. 123. 153. 257. 355. 456. 608.

50 75.6 88.2 96.2 115. 137. 211. 315. 390. 505.

60 73.6 84.0 92.0 107. 125. 186. 267. 334. 399.

70 71.5 75.4 87.2 98.8 115. 172. 233. 269. 342.

75 70.8 74.6 85.2 94.4 112. 166. 210. 247. 319.

80 67.7 71.2 78.8 89.2 109. 160. 198. 237. 302.

90 60.3 67.1 70.4 81.2 101. 141. 167. 202. 268.

95 57.4 61.4 68.0 76.0 96.2 133. 151. 183. 217.

98 53.4 58.1 63.9 71.7 93.0 127. 147. 176. 196.

99 52.3 57.0 62.0 70.4 90.0 125. 145. 171. 191.

03118000 Middle Branch Nimishillen Creek at Canton, Ohio

Years analyzed = 68

Climatic year range = 1941–2008

[APEE, annual percentage equaled or exceeded; ft3/s, cubic foot per second; Sep, September; Nov, November]

Sep–Nov daily mean streamflow (ft3/s) that was equaled or exceeded the indicated percentage of time at APEE level

APEE 98 95 90 80 50 20 10 5 2

1 2.74 5.32 20.8 35.4 82.0 234. 322. 418. 785.

2 2.64 4.91 16.1 25.2 62.0 176. 259. 353. 534.

5 2.28 3.93 7.01 16.8 40.9 112. 183. 193. 216.

10 2.17 3.45 5.66 11.7 24.3 67.7 119. 144. 180.

20 1.78 2.92 4.93 7.52 16.3 38.4 60.1 72.3 85.5

25 1.72 2.67 4.64 6.08 14.0 33.4 48.6 60.6 70.1

30 1.64 2.64 4.03 5.39 13.0 26.8 41.2 51.1 65.2

40 1.44 2.38 3.18 4.55 10.0 20.4 34.4 41.7 56.8

50 1.14 1.99 2.78 3.88 9.05 17.2 27.4 35.2 48.3

60 1.06 1.80 2.29 3.69 7.88 15.2 24.2 31.1 42.4

70 0.95 1.60 2.09 2.92 6.85 14.0 22.1 25.5 37.9

75 0.93 1.55 1.99 2.88 6.75 13.2 21.1 23.5 35.3

80 0.92 1.47 1.79 2.72 6.33 12.2 20.0 21.5 34.1

90 0.82 1.30 1.42 2.31 5.65 11.0 17.3 19.0 30.0

95 0.56 1.04 1.35 1.88 4.94 10.2 14.3 17.8 21.2

98 0.43 0.88 1.15 1.58 4.54 10.0 12.2 16.6 19.1

99 0.36 0.69 0.90 1.58 4.40 9.60 12.2 16.1 18.6
180 Methods for Estimating Selected Low-Flow Statistics and Development of Annual Flow-Duration Statistics for Ohio

03118500 Nimishillen Creek at North Industry, Ohio

Years analyzed = 88

Climatic year range = 1921–2008

[APEE, annual percentage equaled or exceeded; ft3/s, cubic foot per second; Sep, September; Nov, November]

Sep–Nov daily mean streamflow (ft3/s) that was equaled or exceeded the indicated percentage of time at APEE level

APEE 98 95 90 80 50 20 10 5 2

1 92.3 105. 147. 262. 504. 1070. 1450. 2220. 3530.

2 86.0 93.0 119. 195. 400. 909. 1120. 1700. 2070.

5 61.3 67.3 86.9 128. 258. 511. 751. 896. 1180.

10 49.3 60.0 67.8 96.8 167. 322. 492. 575. 707.

20 38.1 49.5 61.8 73.8 118. 218. 266. 363. 399.

25 36.7 47.9 57.9 70.0 107. 201. 240. 303. 351.

30 35.5 44.5 56.0 65.6 102. 170. 221. 270. 295.

40 33.5 40.3 54.7 61.0 90.7 133. 197. 219. 247.

50 29.3 36.4 48.7 56.8 80.5 122. 172. 188. 217.

60 27.6 34.0 45.8 54.8 74.7 117. 158. 170. 194.

70 25.8 31.9 44.3 52.0 71.3 110. 139. 152. 174.

75 25.6 31.3 43.7 50.0 69.0 106. 131. 143. 166.

80 24.6 30.1 42.5 48.8 67.5 103. 126. 138. 162.

90 23.3 26.5 35.7 44.0 64.7 96.0 114. 131. 147.

95 21.7 24.7 33.1 41.8 62.0 89.3 105. 124. 133.

98 18.3 23.4 29.2 40.0 59.3 86.9 99.9 118. 128.

99 16.8 21.4 29.0 39.8 57.5 85.0 97.2 114. 126.

03145000 South Fork Licking River near Hebron, Ohio

Years analyzed = 50

Climatic year range = 1939–2008

[APEE, annual percentage equaled or exceeded; ft3/s, cubic foot per second; Sep, September; Nov, November]

Sep–Nov daily mean streamflow (ft3/s) that was equaled or exceeded the indicated percentage of time at APEE level

APEE 98 95 90 80 50 20 10 5 2

1 35.4 85.8 139. 296. 603. 1210. 1540. 2160. 4460.

2 23.0 85.4 134. 211. 477. 931. 1330. 2070. 2840.

5 15.7 64.2 98.9 178. 299. 512. 814. 1360. 1950.

10 10.8 11.4 51.3 110. 212. 391. 474. 746. 1510.

20 7.87 9.02 21.3 32.8 103. 255. 338. 436. 445.

25 7.20 7.59 9.86 22.6 74.0 171. 274. 323. 405.

30 6.31 7.07 9.26 18.5 47.4 134. 238. 273. 363.

40 5.31 5.96 7.16 12.0 30.8 60.2 122. 188. 324.

50 3.72 5.07 5.73 9.14 20.5 39.8 73.1 134. 242.

60 3.52 4.46 4.92 7.14 15.0 31.2 44.8 84.5 153.

70 3.20 3.73 4.43 6.23 12.3 21.0 34.4 57.8 81.7

75 3.10 3.37 3.93 5.30 10.5 19.0 27.8 49.1 66.9

80 3.00 3.06 3.45 4.93 9.66 17.7 24.3 39.1 51.8

90 2.00 2.18 2.73 3.99 7.76 15.2 19.9 26.3 41.0

95 0.97 1.84 2.43 3.62 6.71 14.5 17.9 22.8 30.7

98 0.78 1.34 2.09 3.57 6.14 13.8 14.9 20.6 24.8

99 0.70 1.30 2.01 3.42 5.95 13.8 14.9 19.8 24.0
Appendix 6 181

03156000 Hunters Run at Lancaster, Ohio

Years analyzed = 23

Climatic year range = 1956–78

[APEE, annual percentage equaled or exceeded; ft3/s, cubic foot per second; Sep, September; Nov, November]

Sep–Nov daily mean streamflow (ft3/s) that was equaled or exceeded the indicated percentage of time at APEE level

APEE 95 90 80 70 50 30 20 10 5

1 1.56 1.96 5.28 8.00 27.0 37.4 61.4 113. 120.

2 1.46 1.76 4.05 7.33 15.1 33.9 55.1 83.7 92.5

5 1.30 1.43 2.65 4.36 7.00 18.5 27.0 41.1 53.2

10 1.10 1.26 2.19 3.13 5.34 9.16 14.0 21.6 25.1

20 1.00 1.12 1.66 2.24 3.40 6.18 7.38 12.6 14.3

25 1.00 1.12 1.58 2.22 2.90 4.94 6.32 9.26 12.3

30 0.95 1.12 1.48 2.02 2.64 4.50 5.96 8.02 10.4

40 0.82 1.02 1.37 1.92 2.24 3.74 4.86 6.05 6.40

50 0.80 0.96 1.28 1.72 2.00 3.12 3.66 5.10 6.22

60 0.78 0.94 1.20 1.52 1.80 2.68 3.18 4.73 5.46

70 0.70 0.86 1.20 1.27 1.60 2.29 2.51 4.42 5.20

75 0.62 0.82 1.10 1.20 1.40 2.04 2.42 4.30 4.86

80 0.54 0.82 1.10 1.12 1.40 1.97 2.22 4.00 4.40

90 0.51 0.58 0.96 1.00 1.22 1.68 1.92 3.05 3.76

95 0.31 0.51 0.78 0.91 1.00 1.38 1.74 2.75 3.46

98 0.22 0.46 0.68 0.89 1.00 1.25 1.57 2.56 3.26

99 0.22 0.46 0.68 0.80 0.95 1.20 1.50 2.48 3.24

03159500 Hocking River at Athens, Ohio

Years analyzed = 47

Climatic year range = 1962–2008

[APEE, annual percentage equaled or exceeded; ft3/s, cubic foot per second; Sep, September; Nov, November]

Sep–Nov daily mean streamflow (ft3/s) that was equaled or exceeded the indicated percentage of time at APEE level

APEE 95 90 80 70 50 30 20 10 5

1 123. 199. 398. 817. 1700. 3800. 5670. 7680. 11200.

2 118. 178. 321. 670. 1440. 2730. 5070. 6860. 9490.

5 112. 156. 282. 377. 885. 1750. 3410. 4710. 6670.

10 105. 134. 214. 256. 511. 1100. 1910. 2990. 3340.

20 82.1 112. 151. 185. 325. 685. 897. 1620. 1850.

25 76.4 104. 142. 167. 287. 512. 710. 1280. 1630.

30 72.1 98.1 132. 159. 244. 442. 627. 1120. 1510.

40 65.8 87.8 116. 136. 187. 303. 503. 855. 1070.

50 62.8 75.0 103. 113. 151. 246. 394. 611. 825.

60 56.0 68.5 94.0 95.6 126. 203. 309. 503. 684.

70 51.5 64.9 83.4 89.6 108. 180. 253. 444. 584.

75 49.4 60.0 78.8 87.0 102. 168. 232. 404. 542.

80 47.7 59.8 72.8 85.1 98.0 151. 221. 371. 481.

90 45.0 57.8 65.8 76.2 92.0 135. 211. 307. 341.

95 43.4 55.6 61.6 73.2 87.0 121. 158. 238. 302.

98 40.7 53.5 60.6 72.3 83.5 111. 146. 217. 268.

99 40.2 52.0 60.6 71.4 83.0 111. 136. 211. 250.
182 Methods for Estimating Selected Low-Flow Statistics and Development of Annual Flow-Duration Statistics for Ohio

03261500 Great Miami River at Sidney, Ohio

Years analyzed = 83

Climatic year range = 1926–2008

[APEE, annual percentage equaled or exceeded; ft3/s, cubic foot per second; Sep, September; Nov, November]

Sep–Nov daily mean streamflow (ft3/s) that was equaled or exceeded the indicated percentage of time at APEE level

APEE 98 95 90 80 50 20 10 5 2

1 61.1 98.2 117. 181. 576. 2750. 4220. 6060. 6710.

2 56.1 92.0 106. 180. 563. 2190. 3930. 5440. 6410.

5 51.7 73.2 87.8 120. 324. 1360. 2330. 3790. 4430.

10 45.2 51.0 68.5 91.6 256. 779. 1510. 2110. 2970.

20 36.3 45.2 53.6 68.9 152. 372. 706. 1180. 1540.

25 35.1 43.6 49.0 64.0 124. 309. 536. 783. 1260.

30 33.4 42.4 47.4 58.8 97.0 273. 392. 640. 1030.

40 30.0 40.0 42.4 50.8 81.0 181. 275. 430. 763.

50 27.8 37.0 39.0 46.0 68.0 138. 223. 362. 523.

60 24.7 34.0 35.7 41.8 61.6 118. 191. 268. 330.

70 23.6 31.2 33.0 36.8 54.8 110. 165. 197. 301.

75 22.7 29.0 32.0 35.0 52.0 102. 151. 174. 283.

80 21.6 26.8 30.0 33.0 50.8 96.5 132. 149. 256.

90 18.9 21.6 26.5 29.2 45.0 76.2 101. 117. 224.

95 16.2 18.6 23.4 28.8 42.0 69.2 92.8 109. 214.

98 11.7 14.8 22.1 26.7 40.8 65.2 86.8 109. 198.

99 10.0 14.4 21.8 26.0 40.0 64.2 85.6 109. 190.

03261950 Loramie Creek near Newport, Ohio

Years analyzed = 45

Climatic year range = 1964–2008

[APEE, annual percentage equaled or exceeded; ft3/s, cubic foot per second; Sep, September; Nov, November]

Sep–Nov daily mean streamflow (ft3/s) that was equaled or exceeded the indicated percentage of time at APEE level

APEE 95 90 80 70 50 30 20 10 5

1 9.12 13.8 30.2 66.8 259. 1050. 1620. 2240. 2870.

2 8.57 11.5 22.7 52.6 248. 792. 1430. 1880. 2470.

5 6.06 7.19 12.6 20.6 127. 420. 846. 1290. 1440.

10 4.80 5.48 7.14 11.9 47.0 224. 366. 502. 729.

20 3.13 3.64 4.42 6.33 17.2 84.6 154. 222. 256.

25 2.83 3.36 3.82 4.98 13.0 49.0 97.6 169. 187.

30 2.56 2.80 3.42 4.47 11.0 26.7 85.0 124. 136.

40 1.54 1.96 2.56 3.24 7.80 15.8 44.8 74.0 84.3

50 1.16 1.36 1.80 2.70 5.50 10.6 34.2 46.4 59.1

60 0.93 1.10 1.44 2.30 3.46 7.60 23.8 34.0 41.9

70 0.61 0.94 1.26 1.87 3.02 5.31 15.5 26.8 33.7

75 0.52 0.83 1.04 1.70 2.50 5.06 11.6 21.0 30.8

80 0.39 0.74 1.02 1.55 2.34 4.27 9.12 15.8 26.9

90 0.25 0.45 0.84 1.08 1.80 2.65 3.80 8.50 10.3

95 0.23 0.35 0.69 0.84 1.26 2.43 2.94 5.76 7.56

98 0.21 0.31 0.57 0.69 1.10 1.99 2.73 4.29 6.03

99 0.20 0.28 0.50 0.64 1.00 1.92 2.58 3.90 5.85
Appendix 6 183

03262000 Loramie Creek at Lockington, Ohio

Years analyzed = 94

Climatic year range = 1915–2008

[APEE, annual percentage equaled or exceeded; ft3/s, cubic foot per second; Sep, September; Nov, November]

Sep–Nov daily mean streamflow (ft3/s) that was equaled or exceeded the indicated percentage of time at APEE level

APEE 98 95 90 80 50 20 10 5 2

1 6.46 11.8 20.0 37.0 341. 1750. 2910. 3670. 4340.

2 6.46 11.1 17.9 34.4 226. 1540. 2420. 3050. 3640.

5 6.10 9.38 13.7 20.0 97.6 820. 1310. 1900. 2460.

10 5.72 8.75 10.9 14.8 48.4 346. 651. 818. 1280.

20 4.50 7.48 8.08 10.0 23.0 155. 248. 312. 785.

25 4.38 6.85 7.70 10.0 19.5 109. 200. 245. 641.

30 4.17 6.58 7.19 9.00 17.4 75.0 136. 180. 494.

40 3.70 5.89 6.60 7.74 13.5 53.2 94.0 126. 353.

50 3.37 5.18 5.95 6.90 12.0 39.0 68.5 91.5 230.

60 3.35 4.80 5.39 6.06 10.0 27.0 53.4 68.1 105.

70 3.10 4.09 4.65 5.20 9.00 22.0 43.5 56.2 74.1

75 2.67 3.85 4.35 5.00 8.60 18.0 40.0 49.5 66.1

80 2.53 3.59 4.15 4.74 8.14 17.0 31.0 44.6 59.2

90 1.83 2.65 3.63 4.20 7.06 14.0 21.6 37.7 44.2

95 1.15 2.20 3.11 3.96 6.65 12.6 19.5 33.6 42.8

98 0.68 2.17 2.70 3.80 6.00 10.8 17.7 28.4 36.0

99 0.50 1.63 2.65 3.70 5.80 10.0 14.0 24.3 33.0

03262700 Great Miami River at Troy, Ohio

Years analyzed = 47

Climatic year range = 1962–2008

[APEE, annual percentage equaled or exceeded; ft3/s, cubic foot per second; Sep, September; Nov, November]

Sep–Nov daily mean streamflow (ft3/s) that was equaled or exceeded the indicated percentage of time at APEE level

APEE 95 90 80 70 50 30 20 10 5

1 141. 184. 259. 394. 1080. 3800. 6270. 10000. 12000.

2 137. 178. 242. 373. 1000. 3270. 5600. 9370. 11100.

5 117. 151. 207. 281. 589. 2080. 3720. 5480. 7370.

10 78.5 115. 145. 226. 399. 837. 1930. 2850. 3560.

20 63.9 91.4 106. 143. 245. 485. 842. 1410. 1740.

25 57.4 83.0 102. 122. 190. 324. 609. 980. 1310.

30 56.0 80.6 94.2 110. 177. 266. 511. 804. 1040.

40 52.8 71.8 79.3 90.5 113. 229. 327. 614. 747.

50 50.2 64.0 72.6 84.8 105. 177. 250. 511. 566.

60 47.3 60.2 67.5 76.4 95.8 155. 219. 389. 441.

70 44.1 48.9 61.0 70.8 86.2 143. 193. 296. 347.

75 40.4 44.6 59.6 67.4 83.0 136. 182. 268. 328.

80 38.0 40.9 57.0 64.3 78.8 131. 173. 232. 266.

90 34.0 38.6 52.0 56.9 72.2 112. 141. 183. 225.

95 31.6 37.5 46.5 50.5 68.6 105. 129. 155. 211.

98 28.4 34.0 40.0 48.0 64.7 100. 114. 146. 195.

99 26.4 32.8 38.8 46.6 64.0 95.8 111. 144. 186.
184 Methods for Estimating Selected Low-Flow Statistics and Development of Annual Flow-Duration Statistics for Ohio

03263000 Great Miami River at Taylorsville, Ohio

Years analyzed = 88

Climatic year range = 1921–2008

[APEE, annual percentage equaled or exceeded; ft3/s, cubic foot per second; Sep, September; Nov, November]

Sep–Nov daily mean streamflow (ft3/s) that was equaled or exceeded the indicated percentage of time at APEE level

APEE 98 95 90 80 50 20 10 5 2

1 108. 192. 232. 299. 1240. 4840. 10300. 12400. 14900.

2 92.6 181. 219. 293. 952. 3980. 8890. 10700. 13100.

5 87.9 145. 179. 238. 664. 2510. 5280. 8080. 10300.

10 82.8 99.8 148. 181. 408. 1480. 2720. 3980. 5200.

20 72.6 85.2 118. 138. 284. 823. 1530. 2000. 3180.

25 69.2 83.5 109. 126. 246. 616. 1070. 1600. 2690.

30 66.9 80.1 104. 116. 215. 519. 952. 1370. 2410.

40 63.2 75.0 90.4 102. 169. 396. 670. 1030. 1830.

50 62.5 70.3 82.7 95.6 148. 285. 507. 748. 1290.

60 59.5 66.9 75.6 88.8 130. 256. 405. 631. 781.

70 54.9 64.9 68.0 82.8 118. 240. 350. 516. 663.

75 53.4 60.9 64.9 79.8 116. 221. 332. 496. 615.

80 53.0 57.4 62.0 74.6 108. 209. 259. 396. 575.

90 45.5 53.5 57.8 66.6 96.2 170. 203. 321. 497.

95 39.9 51.0 54.5 62.8 91.7 157. 194. 255. 463.

98 37.6 47.2 52.6 56.0 84.1 140. 184. 206. 432.

99 35.6 45.9 51.9 55.8 82.5 135. 179. 197. 384.

03266000 Stillwater River at Englewood, Ohio

Years analyzed = 84

Climatic year range = 1925–2008

[APEE, annual percentage equaled or exceeded; ft3/s, cubic foot per second; Sep, September; Nov, November]

Sep–Nov daily mean streamflow (ft3/s) that was equaled or exceeded the indicated percentage of time at APEE level

APEE 98 95 90 80 50 20 10 5 2

1 42.9 57.5 88.5 149. 837. 3920. 6050. 6520. 7490.

2 42.1 55.3 83.4 131. 545. 3260. 5850. 6400. 7380.

5 40.7 48.8 76.6 95.4 258. 1490. 4260. 5230. 6340.

10 38.2 43.8 62.2 79.8 193. 961. 1700. 3150. 3570.

20 30.7 37.1 50.7 65.0 126. 411. 664. 1200. 1890.

25 29.7 34.3 47.0 61.0 115. 320. 479. 987. 1450.

30 29.1 33.4 42.9 58.4 100. 250. 427. 736. 1180.

40 26.5 31.2 38.0 52.4 87.0 190. 324. 541. 830.

50 22.8 26.0 33.5 46.0 72.5 150. 274. 412. 547.

60 19.8 23.0 30.0 40.0 65.9 122. 208. 301. 477.

70 14.9 20.1 22.6 36.6 56.9 106. 166. 266. 451.

75 13.4 19.3 21.0 35.0 53.0 95.0 155. 253. 429.

80 12.8 18.0 19.5 32.0 51.4 88.8 139. 244. 404.

90 11.0 15.4 17.0 25.0 43.6 76.4 118. 230. 284.

95 8.66 12.2 15.0 23.0 40.1 66.6 109. 185. 261.

98 5.53 9.92 13.8 19.8 36.2 63.5 100. 166. 247.

99 5.22 8.65 12.0 19.0 36.0 61.0 99.5 159. 239.
Appendix 6 185

03267900 Mad River at St Paris Pike at Eagle City, Ohio

Years analyzed = 38

Climatic year range = 1965–2008

[APEE, annual percentage equaled or exceeded; ft3/s, cubic foot per second; Sep, September; Nov, November]

Sep–Nov daily mean streamflow (ft3/s) that was equaled or exceeded the indicated percentage of time at APEE level

APEE 95 90 80 70 50 30 20 10 5

1 141. 152. 212. 286. 548. 968. 1500. 2110. 2790.

2 139. 145. 206. 238. 442. 716. 1370. 1810. 2370.

5 129. 136. 170. 201. 274. 418. 807. 965. 1540.

10 121. 130. 153. 177. 217. 306. 444. 614. 887.

20 119. 123. 135. 145. 186. 237. 301. 400. 498.

25 118. 122. 131. 137. 179. 219. 269. 372. 436.

30 115. 118. 127. 132. 171. 210. 250. 355. 416.

40 105. 115. 118. 127. 160. 199. 236. 290. 374.

50 100. 112. 116. 125. 156. 182. 222. 272. 350.

60 99.0 109. 113. 118. 149. 172. 209. 240. 336.

70 97.1 105. 110. 113. 143. 167. 201. 232. 314.

75 97.1 99.8 107. 113. 141. 161. 188. 230. 280.

80 95.5 97.9 105. 112. 137. 156. 174. 207. 238.

90 85.7 96.4 102. 110. 132. 148. 158. 198. 226.

95 83.6 94.4 99.3 109. 129. 143. 157. 196. 222.

98 81.7 93.3 96.8 106. 126. 140. 155. 195. 218.

99 81.7 92.5 95.6 105. 126. 139. 155. 193. 218.

03269000 Buck Creek at Springfield, Ohio

Years analyzed = 33

Climatic year range = 1914–73

[APEE, annual percentage equaled or exceeded; ft3/s, cubic foot per second; Sep, September; Nov, November]

Sep–Nov daily mean streamflow (ft3/s) that was equaled or exceeded the indicated percentage of time at APEE level

APEE 95 90 80 70 50 30 20 10 5

1 51.0 67.0 86.0 148. 225. 486. 743. 880. 915.

2 49.0 62.2 72.4 108. 163. 385. 446. 700. 767.

5 35.1 47.3 57.6 79.2 106. 218. 296. 464. 507.

10 29.2 38.1 47.2 63.4 87.0 114. 197. 234. 316.

20 25.6 32.6 40.0 50.2 65.0 88.8 126. 161. 191.

25 24.6 31.6 39.4 44.0 64.0 80.0 103. 136. 180.

30 24.6 30.2 36.0 40.2 60.8 78.4 101. 125. 159.

40 21.1 27.0 34.4 37.6 53.0 68.9 84.8 99.0 127.

50 18.7 25.8 29.8 36.0 51.0 67.0 76.8 93.6 117.

60 15.3 23.8 28.0 32.4 46.0 60.0 75.4 87.5 105.

70 13.8 23.8 26.0 30.2 46.0 58.1 68.6 80.8 99.5

75 13.2 21.8 25.8 28.6 45.0 56.8 62.4 77.0 97.5

80 11.9 20.4 24.8 28.6 43.0 55.4 61.4 76.4 94.8

90 11.0 17.8 21.0 27.7 36.0 51.4 59.2 74.1 86.4

95 10.8 16.4 19.8 26.7 35.0 49.3 53.2 68.2 82.7

98 9.33 16.0 18.4 24.9 34.0 47.4 52.0 66.4 78.1

99 7.14 16.0 18.4 23.6 34.0 46.0 52.0 58.0 74.2
186 Methods for Estimating Selected Low-Flow Statistics and Development of Annual Flow-Duration Statistics for Ohio

03269500 Mad River near Springfield, Ohio

Years analyzed = 97

Climatic year range = 1904–2008

[APEE, annual percentage equaled or exceeded; ft3/s, cubic foot per second; Sep, September; Nov, November]

Sep–Nov daily mean streamflow (ft3/s) that was equaled or exceeded the indicated percentage of time at APEE level

APEE 98 95 90 80 50 20 10 5 2

1 172. 223. 271. 346. 754. 2130. 3300. 4130. 5690.

2 170. 200. 244. 310. 628. 1660. 2430. 3010. 3640.

5 158. 175. 224. 261. 438. 950. 1420. 1590. 2420.

10 148. 163. 193. 241. 352. 619. 901. 1150. 1430.

20 144. 156. 171. 212. 284. 452. 618. 846. 1250.

25 142. 152. 168. 206. 269. 416. 540. 719. 958.

30 134. 152. 166. 201. 261. 388. 481. 641. 886.

40 132. 147. 161. 190. 245. 350. 410. 572. 760.

50 128. 145. 157. 183. 237. 320. 373. 516. 621.

60 128. 140. 152. 179. 227. 301. 352. 462. 591.

70 115. 135. 148. 173. 212. 290. 343. 408. 560.

75 115. 131. 144. 169. 209. 283. 332. 386. 542.

80 110. 123. 144. 165. 204. 277. 323. 368. 526.

90 102. 123. 137. 155. 194. 260. 306. 336. 479.

95 99.8 118. 132. 146. 189. 250. 296. 318. 445.

98 89.3 115. 125. 141. 184. 245. 280. 306. 382.

99 85.7 113. 123. 140. 183. 242. 270. 297. 380.

03270000 Mad River near Dayton, Ohio

Years analyzed = 91

Climatic year range = 1915–2008

[APEE, annual percentage equaled or exceeded; ft3/s, cubic foot per second; Sep, September; Nov, November]

Sep–Nov daily mean streamflow (ft3/s) that was equaled or exceeded the indicated percentage of time at APEE level

APEE 98 95 90 80 50 20 10 5 2

1 205. 250. 351. 404. 992. 2690. 3820. 4570. 5630.

2 190. 239. 299. 367. 824. 2050. 3180. 3880. 4760.

5 175. 203. 240. 302. 602. 1310. 1940. 2370. 2970.

10 160. 187. 213. 274. 460. 858. 1120. 1600. 1900.

20 157. 173. 203. 252. 359. 628. 722. 1040. 1390.

25 154. 169. 198. 237. 346. 541. 656. 896. 1230.

30 154. 167. 195. 235. 331. 503. 590. 833. 1020.

40 150. 162. 190. 223. 297. 448. 537. 708. 833.

50 147. 158. 182. 216. 283. 402. 488. 675. 770.

60 139. 155. 180. 206. 275. 382. 457. 623. 711.

70 128. 145. 177. 198. 265. 360. 432. 556. 666.

75 127. 141. 163. 193. 257. 347. 412. 484. 638.

80 122. 131. 159. 190. 242. 334. 400. 473. 606.

90 109. 129. 147. 176. 229. 317. 379. 426. 563.

95 106. 125. 144. 170. 219. 310. 352. 412. 508.

98 103. 124. 138. 166. 214. 293. 333. 385. 491.

99 103. 123. 137. 162. 209. 291. 327. 368. 484.
Appendix 6 187

03270500 Great Miami River at Dayton, Ohio

Years analyzed = 96

Climatic year range = 1913–2008

[APEE, annual percentage equaled or exceeded; ft3/s, cubic foot per second; Sep, September; Nov, November]

Sep–Nov daily mean streamflow (ft3/s) that was equaled or exceeded the indicated percentage of time at APEE level

APEE 98 95 90 80 50 20 10 5 2

1 270. 486. 631. 853. 2470. 10800. 19800. 21200. 27500.

2 269. 467. 597. 776. 2310. 9220. 16400. 18500. 22200.

5 260. 336. 512. 630. 1520. 6410. 10100. 14300. 19300.

10 247. 296. 435. 537. 1170. 3240. 5860. 8310. 10300.

20 210. 250. 382. 452. 795. 1910. 2930. 3310. 5370.

25 207. 239. 367. 436. 705. 1440. 2200. 2810. 4860.

30 204. 232. 350. 405. 652. 1240. 2010. 2420. 4240.

40 196. 223. 321. 371. 550. 964. 1640. 2010. 3280.

50 190. 219. 294. 344. 501. 830. 1280. 1740. 2210.

60 184. 212. 278. 320. 449. 743. 1140. 1370. 1980.

70 173. 189. 215. 295. 410. 689. 860. 1180. 1770.

75 158. 184. 205. 286. 395. 641. 814. 1100. 1700.

80 153. 167. 199. 268. 381. 611. 789. 969. 1640.

90 140. 146. 182. 248. 347. 536. 663. 797. 1450.

95 131. 138. 176. 232. 331. 498. 625. 700. 1380.

98 124. 135. 160. 220. 313. 469. 568. 671. 1300.

99 119. 130. 155. 216. 311. 463. 561. 631. 1100.

03271500 Great Miami River at Miamisburg, Ohio

Years analyzed = 54

Climatic year range = 1924–94

[APEE, annual percentage equaled or exceeded; ft3/s, cubic foot per second; Sep, September; Nov, November]

Sep–Nov daily mean streamflow (ft3/s) that was equaled or exceeded the indicated percentage of time at APEE level

APEE 98 95 90 80 50 20 10 5 2

1 344. 521. 643. 935. 2590. 10700. 21500. 23500. 27000.

2 344. 494. 598. 844. 2440. 8470. 18300. 21200. 23700.

5 333. 368. 553. 692. 1830. 6450. 13000. 16400. 18900.

10 300. 342. 519. 590. 1420. 3770. 6730. 9670. 12700.

20 284. 328. 463. 517. 1020. 2210. 3060. 4390. 8450.

25 277. 320. 451. 497. 907. 1610. 2610. 3740. 7760.

30 273. 318. 423. 480. 787. 1410. 2390. 3220. 6730.

40 261. 307. 396. 459. 658. 1060. 2090. 2590. 5400.

50 249. 300. 355. 440. 597. 979. 1770. 2160. 3830.

60 245. 286. 328. 431. 547. 900. 1380. 1830. 3090.

70 240. 265. 294. 418. 513. 828. 1060. 1650. 2670.

75 236. 256. 289. 411. 504. 780. 1010. 1500. 2530.

80 231. 249. 282. 396. 465. 757. 950. 1320. 2350.

90 221. 227. 262. 377. 436. 662. 829. 1110. 2130.

95 201. 220. 249. 338. 423. 650. 798. 1020. 1880.

98 167. 195. 224. 291. 405. 638. 768. 958. 1760.

99 149. 164. 210. 278. 394. 623. 758. 920. 1760.
188 Methods for Estimating Selected Low-Flow Statistics and Development of Annual Flow-Duration Statistics for Ohio

03272000 Twin Creek near Germantown, Ohio

Years analyzed = 86

Climatic year range = 1920–2008

[APEE, annual percentage equaled or exceeded; ft3/s, cubic foot per second; Sep, September; Nov, November]

Sep–Nov daily mean streamflow (ft3/s) that was equaled or exceeded the indicated percentage of time at APEE level

APEE 98 95 90 80 50 20 10 5 2

1 9.27 11.4 26.8 48.6 442. 2090. 4100. 5150. 5970.

2 8.78 11.4 22.2 42.1 307. 1420. 3020. 4240. 4850.

5 7.44 11.2 18.7 29.9 141. 671. 1380. 2030. 2540.

10 7.05 10.1 16.0 23.3 85.1 351. 709. 1020. 1250.

20 6.59 8.94 12.9 18.4 48.0 138. 322. 415. 523.

25 6.39 8.28 12.7 17.4 39.5 96.8 220. 339. 422.

30 6.24 7.69 11.7 16.6 32.0 81.4 192. 274. 381.

40 5.63 6.94 10.0 14.4 27.0 53.7 107. 188. 220.

50 4.87 6.39 9.05 11.4 23.5 41.6 87.6 149. 177.

60 4.27 5.49 7.04 9.54 19.5 35.0 76.2 124. 146.

70 4.07 4.81 5.94 8.54 17.5 30.2 49.4 98.2 125.

75 3.97 4.54 5.89 8.14 15.0 28.0 38.9 86.6 113.

80 3.78 4.15 5.29 7.79 14.0 23.0 33.1 78.6 96.6

90 3.30 3.55 4.55 6.80 12.0 20.6 29.2 56.9 85.5

95 2.89 3.33 3.97 6.28 11.0 18.6 28.7 46.2 67.4

98 2.54 2.84 3.67 5.78 10.0 17.4 26.2 35.2 59.9

99 2.37 2.84 3.54 5.44 10.0 16.6 25.3 35.2 57.3

03274000 Great Miami River at Hamilton, Ohio

Years analyzed = 79

Climatic year range = 1930–2008

[APEE, annual percentage equaled or exceeded; ft3/s, cubic foot per second; Sep, September; Nov, November]

Sep–Nov daily mean streamflow (ft3/s) that was equaled or exceeded the indicated percentage of time at APEE level

APEE 98 95 90 80 50 20 10 5 2

1 469. 676. 908. 1210. 4330. 14100. 26700. 29900. 31700.

2 459. 608. 806. 1130. 3530. 12000. 22400. 25600. 26400.

5 422. 515. 679. 896. 2590. 8950. 14600. 18400. 22100.

10 393. 472. 583. 747. 1800. 4530. 8930. 10600. 12000.

20 356. 399. 532. 647. 1310. 2520. 3610. 5080. 6450.

25 346. 380. 499. 626. 1160. 1910. 3130. 4030. 5680.

30 344. 372. 491. 613. 1030. 1700. 2920. 3410. 4680.

40 324. 363. 469. 574. 841. 1310. 2210. 2890. 3730.

50 312. 355. 445. 531. 748. 1180. 1980. 2480. 2950.

60 297. 340. 399. 509. 675. 1120. 1380. 1950. 2630.

70 281. 330. 366. 466. 652. 958. 1220. 1700. 2320.

75 277. 325. 352. 462. 620. 945. 1190. 1550. 2160.

80 268. 310. 337. 438. 593. 859. 1140. 1490. 2090.

90 250. 288. 308. 414. 508. 765. 947. 1290. 1880.

95 217. 269. 294. 392. 487. 713. 897. 1170. 1680.

98 191. 258. 289. 378. 463. 696. 851. 1060. 1560.

99 177. 246. 267. 357. 458. 683. 846. 974. 1470.
Appendix 6 189

04183500 Maumee River at Antwerp, Ohio

Years analyzed = 57

Climatic year range = 1921–81

[APEE, annual percentage equaled or exceeded; ft3/s, cubic foot per second; Sep, September; Nov, November]

Sep–Nov daily mean streamflow (ft3/s) that was equaled or exceeded the indicated percentage of time at APEE level

APEE 98 95 90 80 50 20 10 5 2

1 231. 277. 376. 530. 2260. 5950. 9500. 11500. 13100.

2 199. 218. 334. 451. 2140. 5400. 8670. 11200. 12900.

5 164. 170. 261. 390. 1310. 3830. 6000. 9580. 10600.

10 143. 160. 218. 307. 823. 2520. 4150. 5930. 7730.

20 120. 126. 178. 225. 513. 1360. 2430. 2850. 5740.

25 112. 119. 165. 206. 410. 1070. 1670. 2440. 4560.

30 107. 113. 156. 190. 375. 870. 1310. 2100. 4050.

40 96.1 103. 140. 163. 306. 550. 854. 1590. 2810.

50 91.6 95.9 122. 143. 275. 426. 585. 1160. 2320.

60 85.1 88.9 110. 130. 212. 353. 456. 870. 1650.

70 75.2 84.3 103. 121. 189. 303. 377. 666. 1300.

75 75.0 82.7 94.4 116. 175. 282. 352. 594. 1110.

80 68.4 76.0 90.0 112. 164. 241. 325. 507. 911.

90 53.9 63.2 74.1 98.2 140. 204. 265. 430. 701.

95 48.1 59.7 68.1 85.7 121. 196. 240. 415. 657.

98 32.4 51.0 64.1 75.6 110. 174. 221. 372. 443.

99 30.8 50.8 61.6 72.8 110. 163. 208. 335. 429.

04185000 Tiffin River at Stryker, Ohio

Years analyzed = 76

Climatic year range = 1921–2008

[APEE, annual percentage equaled or exceeded; ft3/s, cubic foot per second; Sep, September; Nov, November]

Sep–Nov daily mean streamflow (ft3/s) that was equaled or exceeded the indicated percentage of time at APEE level

APEE 98 95 90 80 50 20 10 5 2

1 23.2 36.7 53.0 137. 735. 1240. 1570. 2090. 3100.

2 22.8 35.2 50.4 123. 673. 1200. 1530. 1960. 3040.

5 21.2 32.9 42.9 77.2 366. 938. 1190. 1720. 2290.

10 19.2 29.1 35.3 63.0 221. 648. 989. 1190. 1670.

20 17.2 26.6 30.7 48.2 122. 332. 560. 664. 962.

25 15.2 24.9 29.7 40.4 103. 258. 339. 450. 820.

30 15.2 24.9 28.4 38.8 95.4 202. 317. 376. 657.

40 11.1 22.1 26.0 32.6 70.0 148. 226. 270. 382.

50 10.0 19.5 22.7 27.4 52.5 113. 169. 204. 266.

60 9.62 16.7 20.0 23.4 43.2 85.5 134. 158. 204.

70 8.50 12.1 15.9 19.0 35.1 64.6 98.9 141. 168.

75 7.86 10.7 13.7 17.0 29.5 57.2 86.0 110. 154.

80 7.19 8.82 11.7 16.2 27.2 46.8 68.0 96.1 141.

90 5.82 6.92 10.0 14.0 20.1 37.6 54.2 66.3 116.

95 5.50 5.87 9.37 12.6 19.0 35.1 45.6 56.9 105.

98 4.49 5.14 7.95 11.8 17.9 33.2 41.5 54.5 99.3

99 3.81 5.13 7.88 11.0 17.5 33.2 38.6 53.7 96.9
190 Methods for Estimating Selected Low-Flow Statistics and Development of Annual Flow-Duration Statistics for Ohio

04187500 Ottawa River at Allentown, Ohio

Years analyzed = 52

Climatic year range = 1923–81

[APEE, annual percentage equaled or exceeded; ft3/s, cubic foot per second; Sep, September; Nov, November]

Sep–Nov daily mean streamflow (ft3/s) that was equaled or exceeded the indicated percentage of time at APEE level

APEE 98 95 90 80 50 20 10 5 2

1 23.5 34.6 42.1 63.8 150. 953. 1570. 2230. 2320.

2 21.8 31.4 35.2 42.8 102. 646. 1310. 1960. 2040.

5 15.4 19.9 24.0 29.4 65.3 300. 576. 1080. 1510.

10 13.9 15.0 18.6 24.0 47.1 119. 208. 501. 856.

20 10.1 12.5 16.2 20.6 34.8 55.0 104. 250. 457.

25 9.78 11.7 16.0 19.0 31.0 46.6 82.5 172. 345.

30 9.53 11.3 14.6 18.6 28.5 38.3 67.1 146. 289.

40 9.06 10.7 14.6 18.0 24.0 34.1 49.0 90.6 153.

50 8.68 10.0 12.3 16.6 21.0 30.4 39.0 62.6 101.

60 8.28 9.73 11.3 15.0 20.0 28.9 35.6 47.5 74.0

70 7.96 9.17 11.0 13.6 18.8 27.4 32.5 40.7 59.1

75 7.85 8.86 10.6 13.6 18.5 26.8 31.5 37.7 55.0

80 7.66 8.73 10.3 12.6 18.5 25.4 30.8 34.7 50.4

90 7.06 8.23 9.55 12.0 16.6 23.8 28.1 32.3 41.6

95 6.83 7.76 9.34 11.0 16.0 22.2 25.0 30.7 34.4

98 6.04 6.98 8.86 9.87 14.4 20.7 23.6 28.2 30.7

99 5.60 6.64 8.56 9.66 14.0 20.4 23.0 27.7 29.9

04191500 Auglaize River near Defiance, Ohio

Years analyzed = 94

Climatic year range = 1915–2008

[APEE, annual percentage equaled or exceeded; ft3/s, cubic foot per second; Sep, September; Nov, November]

Sep–Nov daily mean streamflow (ft3/s) that was equaled or exceeded the indicated percentage of time at APEE level

APEE 98 95 90 80 50 20 10 5 2

1 135. 259. 514. 879. 3260. 11600. 14000. 17700. 22300.

2 132. 239. 386. 674. 3020. 10100. 12600. 15000. 22100.

5 97.1 163. 239. 341. 1480. 6860. 9860. 11000. 16000.

10 59.6 102. 138. 238. 933. 2910. 6150. 7600. 12700.

20 43.8 60.3 84.1 118. 401. 1260. 2550. 4320. 8920.

25 38.3 44.8 59.0 102. 288. 833. 1780. 2620. 6680.

30 34.5 39.4 50.9 79.2 229. 681. 1220. 1870. 5720.

40 29.6 33.6 37.2 56.8 153. 473. 848. 1200. 2990.

50 22.7 30.0 35.0 48.0 117. 322. 634. 912. 2110.

60 21.4 30.0 31.3 39.6 82.4 224. 416. 816. 1240.

70 18.5 21.8 29.3 34.0 56.9 175. 283. 536. 869.

75 14.0 19.8 27.0 30.0 48.5 165. 257. 452. 696.

80 13.4 19.3 24.0 29.0 44.5 113. 215. 428. 629.

90 7.28 14.8 20.0 25.2 37.3 71.0 147. 243. 385.

95 5.06 10.2 15.5 21.6 33.0 57.8 104. 180. 245.

98 1.87 6.67 9.66 20.0 30.0 47.8 62.4 102. 140.

99 1.49 5.65 9.20 19.0 29.0 46.0 58.5 88.5 119.
Appendix 6 191

04192500 Maumee River near Defiance, Ohio

Years analyzed = 77

Climatic year range = 1924–2008

[APEE, annual percentage equaled or exceeded; ft3/s, cubic foot per second; Sep, September; Nov, November]

Sep–Nov daily mean streamflow (ft3/s) that was equaled or exceeded the indicated percentage of time at APEE level

APEE 98 95 90 80 50 20 10 5 2

1 248. 370. 750. 1100. 9120. 22000. 27900. 31700. 42900.

2 244. 358. 627. 866. 7970. 20800. 26400. 30700. 39500.

5 196. 256. 492. 640. 4650. 15300. 20100. 24500. 28600.

10 165. 241. 386. 520. 2700. 8170. 12900. 18900. 24500.

20 131. 188. 299. 404. 1390. 4080. 7280. 9840. 17100.

25 123. 178. 244. 342. 1130. 2790. 5040. 7390. 14400.

30 114. 165. 227. 314. 943. 2410. 4200. 5830. 11800.

40 99.7 154. 189. 284. 675. 1340. 2520. 3810. 8510.

50 78.2 138. 165. 232. 506. 959. 1740. 2880. 5630.

60 69.3 123. 157. 207. 398. 744. 1380. 2020. 3870.

70 62.1 93.5 117. 182. 339. 574. 1050. 1640. 2550.

75 57.0 81.6 114. 170. 303. 526. 906. 1570. 2140.

80 55.2 75.3 105. 160. 273. 455. 831. 1440. 1770.

90 48.6 62.4 75.6 128. 234. 376. 643. 927. 1230.

95 21.3 61.2 69.6 111. 215. 338. 557. 830. 994.

98 11.6 47.9 58.0 84.6 198. 294. 467. 640. 811.

99 4.68 41.8 53.4 84.6 170. 280. 393. 609. 745.

04193500 Maumee River at Waterville, Ohio

Years analyzed = 87

Climatic year range = 1899–2008

[APEE, annual percentage equaled or exceeded; ft3/s, cubic foot per second; Sep, September; Nov, November]

Sep–Nov daily mean streamflow (ft3/s) that was equaled or exceeded the indicated percentage of time at APEE level

APEE 98 95 90 80 50 20 10 5 2

1 423. 629. 865. 1250. 9090. 24900. 30700. 36300. 47000.

2 361. 526. 813. 1150. 8550. 22900. 28200. 35500. 43200.

5 299. 416. 570. 781. 5530. 16700. 21500. 29400. 34100.

10 246. 291. 442. 601. 3150. 8770. 13800. 20900. 28300.

20 158. 202. 253. 399. 1540. 4900. 7480. 9950. 20300.

25 102. 113. 199. 353. 1180. 3000. 4740. 7570. 16500.

30 77.6 96.0 182. 320. 1000. 2280. 4090. 5720. 12600.

40 70.4 89.4 159. 275. 737. 1480. 2680. 3830. 8780.

50 64.1 80.0 126. 202. 574. 1080. 1960. 2960. 6280.

60 35.2 70.0 89.2 169. 425. 870. 1690. 2070. 3640.

70 32.8 53.1 70.0 150. 348. 618. 1320. 1640. 2760.

75 16.4 47.2 70.0 145. 295. 544. 1060. 1510. 2310.

80 16.4 44.9 67.5 128. 263. 494. 923. 1340. 1990.

90 8.80 35.4 63.2 100. 213. 410. 662. 1020. 1300.

95 8.80 30.2 52.4 88.9 180. 356. 584. 860. 999.

98 5.00 26.8 38.6 68.8 154. 303. 492. 601. 933.

99 5.00 24.4 33.0 64.2 146. 281. 458. 548. 914.
192 Methods for Estimating Selected Low-Flow Statistics and Development of Annual Flow-Duration Statistics for Ohio

04195500 Portage River at Woodville, Ohio

Years analyzed = 58

Climatic year range = 1951–2008

[APEE, annual percentage equaled or exceeded; ft3/s, cubic foot per second; Sep, September; Nov, November]

Sep–Nov daily mean streamflow (ft3/s) that was equaled or exceeded the indicated percentage of time at APEE level

APEE 98 95 90 80 50 20 10 5 2

1 13.4 16.9 47.8 82.8 1090. 2720. 3790. 5250. 5950.

2 12.3 14.9 43.3 66.6 841. 2450. 3330. 4720. 5090.

5 11.1 13.9 34.3 43.6 363. 1330. 1770. 3440. 4320.

10 9.19 10.9 25.1 32.0 157. 612. 1010. 1820. 2310.

20 7.92 9.90 15.6 22.3 53.9 242. 416. 998. 1180.

25 6.95 9.67 14.0 19.6 44.5 153. 318. 658. 963.

30 6.10 9.50 12.0 17.6 35.6 114. 286. 442. 720.

40 5.23 8.58 10.9 14.2 27.5 76.4 158. 337. 541.

50 4.42 7.61 9.24 12.0 22.0 56.8 96.0 235. 336.

60 4.02 6.03 7.16 10.0 18.0 42.8 73.1 173. 213.

70 3.37 4.92 6.21 9.10 14.9 30.8 59.6 106. 151.

75 3.23 4.28 5.60 8.70 13.5 28.0 50.7 88.5 124.

80 2.97 3.87 5.37 8.13 12.0 21.8 43.2 80.7 105.

90 2.65 3.56 4.59 6.72 10.0 18.0 27.5 49.1 78.9

95 2.23 3.17 4.33 6.04 8.88 15.7 22.0 39.6 71.4

98 2.07 2.29 3.46 5.18 8.04 14.2 18.6 32.4 63.1

99 1.82 2.09 3.46 5.04 7.75 14.0 16.3 32.4 63.1

04196000 Sandusky River near Bucyrus, Ohio

Years analyzed = 56

Climatic year range = 1925–2008

[APEE, annual percentage equaled or exceeded; ft3/s, cubic foot per second; Sep, September; Nov, November]

Sep–Nov daily mean streamflow (ft3/s) that was equaled or exceeded the indicated percentage of time at APEE level

APEE 98 95 90 80 50 20 10 5 2

1 12.7 19.5 26.2 48.0 277. 855. 1270. 1420. 1420.

2 6.72 12.7 23.1 38.4 210. 646. 875. 1120. 1350.

5 3.05 8.37 11.8 18.4 112. 275. 568. 732. 750.

10 2.16 5.30 8.20 11.7 53.1 132. 237. 258. 397.

20 1.61 3.50 5.29 7.50 25.7 65.5 108. 154. 176.

25 1.55 3.18 4.27 6.28 17.0 48.6 68.2 108. 138.

30 1.47 3.15 3.78 5.94 14.2 39.8 58.7 88.6 118.

40 1.31 2.61 3.28 5.00 10.0 26.3 44.7 59.9 85.8

50 1.20 2.06 2.87 4.24 8.20 19.0 31.8 46.0 64.0

60 1.17 1.77 2.54 3.04 6.66 14.0 24.2 38.4 48.6

70 1.06 1.49 1.95 2.64 5.38 11.4 17.0 28.2 38.8

75 1.04 1.38 1.64 2.54 4.75 10.0 14.3 25.6 36.7

80 1.00 1.26 1.50 2.32 4.20 9.78 12.0 24.4 33.5

90 0.90 1.16 1.30 1.95 3.33 6.50 8.72 14.6 23.9

95 0.81 0.90 1.17 1.54 3.01 5.50 7.92 12.1 19.6

98 0.60 0.70 0.95 1.33 2.68 4.69 5.95 8.27 14.3

99 0.60 0.69 0.87 1.20 2.40 4.20 5.33 6.95 14.2
Appendix 6 193

04196800 Tymochtee Creek at Crawford, Ohio

Years analyzed = 37

Climatic year range = 1972–2008

[APEE, annual percentage equaled or exceeded; ft3/s, cubic foot per second; Sep, September; Nov, November]

Sep–Nov daily mean streamflow (ft3/s) that was equaled or exceeded the indicated percentage of time at APEE level

APEE 95 90 80 70 50 30 20 10 5

1 6.78 8.48 27.0 57.2 516. 1070. 1880. 2570. 2710.

2 5.08 6.64 25.3 52.2 424. 978. 1570. 2330. 2530.

5 4.23 5.43 15.6 34.9 202. 648. 978. 1360. 1620.

10 2.91 4.16 13.8 25.2 63.6 291. 564. 981. 1260.

20 1.84 3.31 6.07 17.2 24.6 103. 208. 403. 629.

25 1.50 3.06 4.76 13.0 20.0 63.6 162. 268. 467.

30 1.26 2.49 4.09 8.22 17.0 47.4 116. 198. 291.

40 1.05 1.80 2.73 4.25 11.2 32.2 76.0 102. 180.

50 0.77 0.88 1.84 3.20 6.60 26.4 47.0 81.2 101.

60 0.56 0.61 1.09 2.07 5.30 15.9 36.5 50.0 70.3

70 0.20 0.40 0.85 1.29 4.06 12.4 25.8 32.8 59.3

75 0.15 0.32 0.62 0.98 2.40 11.6 19.6 26.4 52.4

80 0.11 0.25 0.48 0.83 1.90 10.1 13.4 22.0 48.2

90 0.08 0.10 0.30 0.50 1.30 5.42 8.70 15.4 28.7

95 0.06 0.07 0.18 0.39 0.94 3.90 5.80 12.9 25.2

98 0.01 0.02 0.14 0.34 0.81 2.52 4.74 11.6 22.0

99 0.01 0.02 0.09 0.30 0.68 2.02 4.34 11.4 22.0

04200500 Black River at Elyria, Ohio

Years analyzed = 65

Climatic year range = 1944–2008

[APEE, annual percentage equaled or exceeded; ft3/s, cubic foot per second; Sep, September; Nov, November]

Sep–Nov daily mean streamflow (ft3/s) that was equaled or exceeded the indicated percentage of time at APEE level

APEE 98 95 90 80 50 20 10 5 2

1 11.6 30.3 56.2 82.0 1050. 2420. 3570. 4560. 6390.

2 11.1 26.0 47.0 65.4 840. 2030. 3040. 3660. 5320.

5 10.4 19.3 33.2 45.8 378. 1170. 1860. 2330. 3340.

10 9.51 17.9 24.5 36.2 179. 535. 843. 1440. 2270.

20 7.64 12.5 17.0 28.6 74.0 207. 345. 710. 1040.

25 6.78 11.9 15.0 23.2 58.0 158. 263. 533. 800.

30 5.44 11.3 13.6 18.6 47.8 122. 222. 409. 621.

40 4.23 9.67 11.6 15.2 31.2 72.2 138. 232. 406.

50 3.98 6.77 9.36 14.0 23.0 50.4 101. 155. 296.

60 3.04 6.20 8.47 10.8 18.0 35.8 72.9 107. 204.

70 2.47 4.82 7.28 8.52 15.0 27.8 57.8 88.8 151.

75 2.26 3.96 6.68 7.56 13.0 25.0 52.4 80.0 128.

80 2.07 3.59 5.90 7.40 11.0 22.3 46.4 66.3 106.

90 1.52 2.72 4.87 5.76 9.22 18.0 26.6 34.3 46.8

95 1.20 2.47 4.11 5.04 7.60 13.9 18.6 22.8 28.7

98 0.91 1.98 3.60 4.58 6.20 12.0 14.7 18.5 24.4

99 0.82 1.58 2.94 3.82 5.70 11.8 14.4 17.4 22.4
194 Methods for Estimating Selected Low-Flow Statistics and Development of Annual Flow-Duration Statistics for Ohio

04201500 Rocky River near Berea, Ohio

Years analyzed = 78

Climatic year range = 1923–2008

[APEE, annual percentage equaled or exceeded; ft3/s, cubic foot per second; Sep, September; Nov, November]

Sep–Nov daily mean streamflow (ft3/s) that was equaled or exceeded the indicated percentage of time at APEE level

APEE 98 95 90 80 50 20 10 5 2

1 19.6 29.9 60.5 250. 1350. 3380. 4190. 4810. 8610.

2 19.2 25.6 51.1 163. 988. 2300. 3210. 3890. 4670.

5 16.6 17.4 36.8 103. 454. 1070. 1860. 2420. 2910.

10 11.7 14.8 19.9 70.3 236. 579. 824. 1360. 1730.

20 8.88 11.9 16.3 37.9 115. 267. 395. 589. 1010.

25 7.43 9.92 15.5 28.6 92.5 187. 278. 456. 815.

30 5.87 8.93 14.5 25.6 75.3 160. 226. 349. 614.

40 4.28 6.98 11.2 19.0 56.5 111. 146. 238. 445.

50 3.40 5.90 6.91 15.8 45.0 81.2 117. 187. 317.

60 2.32 4.09 5.48 12.6 36.4 63.4 90.8 152. 216.

70 1.51 3.37 4.75 8.60 27.5 51.2 70.2 130. 164.

75 1.43 3.00 4.19 7.98 24.6 47.4 62.3 108. 147.

80 1.14 2.59 4.05 7.06 22.6 43.7 54.8 85.7 121.

90 0.81 1.87 3.35 5.80 18.1 34.7 40.3 53.3 91.6

95 0.63 1.85 2.65 4.77 13.6 28.6 34.7 41.2 58.0

98 0.44 1.17 2.46 3.71 12.4 24.7 28.5 36.0 39.9

99 0.26 1.17 2.38 3.56 11.0 24.0 28.5 36.0 38.0

04208000 Cuyahoga River at Independence, Ohio

Years analyzed = 80

Climatic year range = 1921–2008

[APEE, annual percentage equaled or exceeded; ft3/s, cubic foot per second; Sep, September; Nov, November]

Sep–Nov daily mean streamflow (ft3/s) that was equaled or exceeded the indicated percentage of time at APEE level

APEE 98 95 90 80 50 20 10 5 2

1 158. 285. 381. 708. 2430. 4450. 5620. 7430. 12800.

2 149. 250. 333. 622. 1840. 3460. 4390. 5900. 9140.

5 124. 184. 246. 477. 1150. 2340. 3270. 3750. 4330.

10 108. 142. 199. 357. 858. 1660. 2030. 2540. 3040.

20 94.1 130. 160. 273. 519. 1010. 1270. 1730. 2140.

25 88.5 122. 147. 247. 432. 874. 1190. 1600. 1840.

30 83.2 116. 138. 211. 368. 751. 1000. 1240. 1510.

40 75.0 112. 128. 161. 325. 590. 848. 1070. 1220.

50 69.5 104. 118. 139. 280. 509. 705. 855. 1040.

60 62.0 97.8 107. 129. 232. 437. 539. 725. 876.

70 57.1 82.5 99.1 115. 208. 388. 442. 524. 726.

75 53.5 80.3 90.5 109. 197. 354. 414. 490. 644.

80 50.0 76.1 84.5 106. 178. 315. 390. 440. 610.

90 43.1 69.2 74.8 97.6 149. 249. 327. 382. 509.

95 34.1 60.7 69.7 85.0 138. 228. 279. 312. 332.

98 30.3 52.8 62.4 74.3 127. 216. 271. 293. 326.

99 24.9 45.0 58.1 72.2 124. 208. 267. 289. 323.
Appendix 6 195

04209000 Chagrin River at Willoughby, Ohio

Years analyzed = 73

Climatic year range = 1925–2008

[APEE, annual percentage equaled or exceeded; ft3/s, cubic foot per second; Sep, September; Nov, November]

Sep–Nov daily mean streamflow (ft3/s) that was equaled or exceeded the indicated percentage of time at APEE level

APEE 98 95 90 80 50 20 10 5 2

1 98.4 124. 248. 344. 1660. 3260. 4250. 5420. 8660.

2 86.1 118. 215. 290. 1180. 2540. 2960. 3840. 6300.

5 70.0 96.2 141. 176. 746. 1350. 1500. 2080. 2950.

10 54.8 74.9 93.5 145. 386. 775. 1010. 1250. 1580.

20 41.9 53.0 59.6 98.4 217. 446. 531. 652. 880.

25 39.4 46.4 53.0 86.0 186. 356. 421. 528. 738.

30 35.4 42.7 49.3 67.4 138. 288. 370. 469. 647.

40 30.9 35.2 41.8 55.4 110. 206. 273. 327. 481.

50 25.0 28.7 36.2 46.8 98.0 155. 212. 244. 388.

60 23.0 27.0 31.9 39.3 78.0 127. 165. 195. 276.

70 20.3 24.1 27.2 33.0 61.6 106. 136. 145. 229.

75 20.0 22.4 26.0 30.0 53.0 102. 129. 135. 183.

80 18.4 20.7 23.4 27.8 47.4 97.5 116. 123. 164.

90 14.7 16.8 19.1 25.8 39.0 68.6 87.2 102. 115.

95 10.8 13.8 16.6 20.6 32.6 58.0 73.0 92.2 99.9

98 6.91 12.7 15.3 19.8 30.8 53.7 66.9 77.5 94.5

99 6.82 12.1 14.4 18.8 30.0 52.0 61.8 76.2 93.8

04211500 Mill Creek near Jefferson, Ohio

Years analyzed = 33

Climatic year range = 1942–74

[APEE, annual percentage equaled or exceeded; ft3/s, cubic foot per second; Sep, September; Nov, November]

Sep–Nov daily mean streamflow (ft3/s) that was equaled or exceeded the indicated percentage of time at APEE level

APEE 95 90 80 70 50 30 20 10 5

1 6.04 15.0 97.2 256. 728. 1100. 1220. 1950. 2470.

2 4.16 8.19 48.6 172. 549. 951. 1010. 1100. 1380.

5 0.27 2.52 18.7 47.6 183. 397. 570. 667. 877.

10 0.24 0.61 1.88 10.6 74.4 206. 276. 408. 507.

20 0.00 0.00 0.10 2.32 41.0 70.0 140. 261. 282.

25 0.00 0.00 0.10 1.26 17.0 50.6 99.2 216. 224.

30 0.00 0.00 0.00 0.16 8.74 36.3 81.8 152. 171.

40 0.00 0.00 0.00 0.14 2.40 13.7 58.9 67.5 114.

50 0.00 0.00 0.00 0.10 0.75 6.34 29.0 36.8 52.6

60 0.00 0.00 0.00 0.01 0.10 1.74 9.78 20.7 35.0

70 0.00 0.00 0.00 0.01 0.10 0.40 3.29 13.4 25.9

75 0.00 0.00 0.00 0.00 0.10 0.34 2.34 8.64 22.1

80 0.00 0.00 0.00 0.00 0.10 0.10 1.29 5.98 16.3

90 0.00 0.00 0.00 0.00 0.05 0.10 0.12 1.68 5.25

95 0.00 0.00 0.00 0.00 0.05 0.10 0.10 1.14 3.38

98 0.00 0.00 0.00 0.00 0.05 0.10 0.10 0.50 2.64

99 0.00 0.00 0.00 0.00 0.05 0.10 0.10 0.50 2.32


Koltun and Kula—Methods for Estimating Selected Low-Flow Statistics and Development of Annual Flow-Duration Statistics for Ohio—SIR 2012–5138