Blank Page 
Analysis of the Magnitude and Frequency of 


Peak Discharges for the Navajo Nation in


Arizona, Utah, Colorado, and New Mexico


By Scott D. Waltemeyer 

Prepared in cooperation with the Bureau ofIndian Affairs 

Scientific Investigations Report 2006–5306 

U.S. Department of the Interior 

U.S. Geological Survey 
U.S. Department of the Interior 

DIRK KEMPTHORNE, Secretary 

U.S. Geological Survey 

Mark D. Myers, Director 

U.S. Geological Survey, Reston, Virginia: 2006 

For sale by U.S. Geological Survey, Information Services


Box 25286, Denver Federal Center


Denver, CO 80225


For more information about the USGS and its products:


Telephone: 1-888-ASK-USGS


World Wide Web: http://www.usgs.gov/


Any use of trade, product, or firm names in this publication 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 materials contained within this report.


Suggested citation: 

Waltemeyer, S.D., 2006, Analysis of the magnitude and frequency of peak discharges for the Navajo Nation in Arizona, 

Utah, Colorado, and New Mexico: U.S. Geological Survey Scientific Investigations Report 2006–5306, 42 p. 
iii 

Contents 

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


Appendix 1—Selected Basin, Climatic, and Flood Characteristics, Maximum Peak Discharge 


Recorded, and Low-Discharge Threshold for Gaging Stations in Flood Regions 8, 11,High


Appendix 2—Basin and Climatic Characteristics Determined Using Geographical Information 


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


Purpose and Scope . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3


Description of Study Area. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3


Analysis of Magnitude and Frequency of PeakDischarges . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3


Station Flood-FrequencyAnalysis. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3


Regional Flood-Frequency Analysis . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 4


Determination of Basin and Climatic Characteristics. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 4


Geographical Information System . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5


Basin and Climatic Characteristics. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5


Development of Generalized Least-Squares Regression Equations . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 7


Improvement of Estimates at Gaging Stations . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 8


Limitations and Accuracyof Regression Equations . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 8


Estimate of Magnitude and Frequency of Peak Discharges at Ungaged Sites . . . . . . . . . . . . . . . . . . . . . . . . . 8


Ungaged Site on anUngaged Stream . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 9


Ungaged Site on a Stream Having a Nearby Gaging Station . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 9


Summary . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 9


References Cited . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 10


Elevation, and 6 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 13


System Weasel . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 37


Figure 

1.	 Map showing boundaries, flood regions, and locations of gaging stations in the 


Navajo Nation and surrounding region . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2


Tables 

1.	 Range of statistically significant basin characteristics selected for use in the regression 


analysis . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6


2. 	 Regional flood-frequency equations using generalized least-squares regression . . . . . . . . . . . . . . . . . . 7

iv 

Conversion Factors and Datums 

Multiply By To obtain 

inch 25.40 millimeter 

foot (ft) 0.3048 meter (m) 

mile (mi) 1.609 kilometer (km) 

square mile (mi2

) 2.590 square kilometer 

cubic foot per second (ft3/s) 0.02832 cubic meter per second 

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


Vertical coordinate information is referenced to the North American Vertical Datum of 1988 


(NAVD 88).


Elevation, as used in this report, refers to distance above the vertical datum.

Analysis of the Magnitude and Frequency of 

Peak Discharges for the Navajo Nation in 

Arizona, Utah, Colorado, and New Mexico 

By Scott D. Waltemeyer 

Abstract 

Estimates of the magnitude and frequency of peak discharges are necessary for the reliable flood-hazard mapping 

in the Navajo Nation in Arizona, Utah, Colorado, and New 

Mexico. The Bureau of Indian Affairs, U.S. Army Corps of 

Engineers, and Navajo Nation requested that the U.S. Geological Survey update estimates of peak discharge magnitude for 

gaging stations in the region and update regional equations for 

estimation of peak discharge and frequency at ungaged sites. 

Equations were developed for estimating the magnitude of 

peak discharges for recurrence intervals of 2, 5, 10, 25, 50, 100, 

and 500 years at ungaged sites using data collected through 

1999 at 146 gaging stations, an additional 13 years of peakdischarge data since a 1997 investigation, which used gagingstation data through 1986. The equations for estimation of peak 

discharges at ungaged sites were developed for flood regions 8, 

11, high elevation, and 6 and are delineated on the basis of the 

hydrologic codes from the 1997 investigation. 

Peak discharges for selected recurrence intervals were 

determined at gaging stations by fitting observed data to a 

log-Pearson Type III distribution with adjustments for a 

low-discharge threshold and a zero skew coefficient. A lowdischarge threshold was applied to frequency analysis of 82 of 

the 146 gaging stations. This application provides an improved 

fit of the log-Pearson Type III frequency distribution. Use of the 

low-discharge threshold generally eliminated the peak discharge having a recurrence interval of less than 1.4 years in the 

probability-density function. 

Within each region, logarithms of the peak discharges for 

selected recurrence intervals were related to logarithms of basin 

and climatic characteristics using stepwise ordinary leastsquares regression techniques for exploratory data analysis. 

Generalized least-squares regression techniques, an improved 

regression procedure that accounts for time and spatial sampling errors, then was applied to the same data used in the ordinary least-squares regression analyses. The average standard 

error of prediction for a peak discharge have a recurrence interval of 100-years for region 8 was 53 percent (average) for the 

100-year flood. The average standard of prediction, which 

includes average sampling error and average standard error of 

regression, ranged from 45 to 83 percent for the 100-year flood. 

Estimated standard error of prediction for a hybrid method for 

region 11 was large in the 1997 investigation. No distinction of 

floods produced from a high-elevation region was presented in 

the 1997 investigation. Overall, the equations based on generalized least-squares regression techniques are considered to be 

more reliable than those in the 1997 report because of the 

increased length of record and improved GIS method. 

Techniques for transferring flood-frequency relations 

to ungaged sites on the same stream can be estimated at an 

ungaged site by a direct application of the regional regression 

equation or at an ungaged site on a stream that has a gaging 

station upstream or downstream by using the drainage-area 

ratio and the drainage-area exponent from the regional regression equation of the respective region. 

Introduction 

Estimates of the magnitude and frequency of peak discharges at unregulated streams at gaging stations or ungaged 

stream sites in the Navajo Nation in Arizona, Utah, Colorado, 

and New Mexico (fig. 1) are necessary for reliable flood-hazard 

mapping. The 100-year recurrence interval is mandated by the 

Federal Emergency Management Agency for mapping floodhazard areas for housing development. The magnitude of the 

peak discharge with a 100-year recurrence interval has an 

annual exceedance frequency of 1 percent and occurs, on average, at least once in a 100-year period. The United States Congress authorized the U.S. Army Corps of Engineers (USACE) 

to map flood-hazard areas for the Navajo Nation. The Bureau of 

Indian Affairs, USACE, and Navajo Nation requested that the 

U.S. Geological Survey (USGS) update estimates of peak discharge magnitude for gaging stations in the region and update 

regional equations for estimation of peak discharge and frequency at ungaged sites. 
Magnitude and 

Frequency of Peak

Discharges for the

Navajo Nation in Arizona, 

Utah, Colorado, and New

Mexico

2 

143

Magnitude and Frequency of Peak Discharges for the Navajo Nation in Arizona, Utah, Colorado, and New Mexico 

114° 112° 111° 110° 109° 108° 107° 106°

40°

40°

113°

COLORADO UTAH

UTAH

NEW MEXICO ARIZONA

NEVADA

Flood Region 11

Navajo Nation

boundary

COLORADO

PLATEAU

PROVINCE

B A

S I N

A

N

D

R

A

N

G

E

P R O V I N C E

ROCKY MOUNTAINS

STUDY AREA

Flood Region 8

Flood Region 6

Utah

Arizona

Utah

Map

location

Colorado

New

Mexico

105

104

103

102

100 101

99

98 97

123

122

121

120

119

118

117

116

115

114

113

112

111 110

109

108

107

106

96

95

94

93

92

91

90

89

88

87

86

85

84

83

82

81 80

79

78

77

76

75

74

73

72

71

70

69

68

67

66

65

63 64

9

8

7

6

4 5

3

2

1

62

61

60 59

56

57 58

55

54

53

52

51 50

49

48

47

46

45

44

43

42

41

40

39

38

37

36

35

34

33

32

31

30

29

28 27

26

25

24

23

21 22

20

19

18

17

15 16

14 13

12

10 11

146

145

144

143

142

141

140

139

136

135

134

133

132

131 130

124

138

137

129

128

127 126

125

39°

38°

37°

36°

35°

34°

33°

39°

38°

37°

36°

35°

34°

33°

113° 112° 111° 110° 109° 108° 107° 106° U.S. Geological Survey digital data 1:500,000

Lambert NAD 83 meters EXPLANATION

0 50 100 MILES Major basin divide Streamflow-gaging station

and identifier

0 50 100 KILOMETERS Physiographic Province Low elevation—Less than

boundary 7,500 feet

High elevation—More 119

than 7,500 feet

Figure 1. Boundaries, flood regions, and locations of gaging stations in the Navajo Nation and surrounding region. 
Analysis of Magnitude and Frequency of Peak Discharges 3 

The most recent publication for estimating magnitude and 

frequency of floods for the Navajo Nation and surrounding 

region was completed in 1997 (Thomas and others, 1997). 

Thomas and others (1997) included analysis of flood data collected for about 1,300 gaging stations from beginning of record 

through 1986 and presented equations for estimation of peak 

discharges for various frequencies based on basin and climatic 

characteristics for 15 physiographic regions in the western 

United States. Thomas and others (1997) determined that the 

use of a zero for the generalized skew coefficient and a lowdischarge threshold improved the fit of the log-Pearson III 

distribution to recorded peak discharge data in the southwestern 

United States. In addition to the investigation by Thomas 

and others (1997), another statistical regression analysis 

approach—generalized least squares (Stedinger and Tasker, 

1985), also has statistically improved estimation of regional 

flood-frequency relations and is used in this report. 

Purpose andScope 

This report presents updated estimates of the magnitude 

and frequency of peak discharges at gaging stations based on 13 

additional years (since 1986) of data collected since the Thomas 

and others (1997) investigation and improved equations for 

estimates of magnitude and frequency of peak discharges at 

ungaged sites. The report presents new and updated basin and 

climatic characteristics using an improved geographical information system (raster modeling) and the National Elevation 

Dataset. The magnitudes of peak discharges were determined 

for recurrence intervals of 2, 5, 10, 25, 50, 100, and 500 years 

for 146 unregulated gaging stations. The frequency analyses are 

based on data for 146 gaging stations that generally have 10 

or more years of record. The equations for estimation of peak 

discharges at ungaged sites were developed for four flood 

regions—regions 8, 11, high elevation, and 6. Also presented in 

this report is the average basin slope and a discussion of significant improvements in the prediction error of the regression 

models, which is attributed to the improved accuracy in the 

determination of drainage area and average basin elevation. 

Description of Study Area 

The physiography of the Navajo Nation and surrounding 

region is varied and complex and includes mountains, plains, 

plateaus, valleys, and deserts. The Rocky Mountains end in 

northern New Mexico, bounding the region on the east. The 

Colorado Plateau Province in the northern part of the study area 

consists of nearly horizontal layers of sedimentary rocks, generally ranges in elevation from about 5,000 to 11,000 ft, and has 

many canyons and escarpments. Landforms include plains, plateaus, pediments, and isolated mountains. The Basin and Range 

Province in the western and southern part of the study area has 

mostly isolated block mountains separated by aggraded desert 

plains. The southeast mountains commonly rise abruptly from 

the valley floors and have piedmont plains that extend downward to neighboring basin floors. Several flat desert areas are 

interspersed between the mountains, and some of these areas are 

lake deposits that have not been covered with water for hundreds of years. Many of the piedmont plains contain distributary-flow areas that consist of material deposited by mountainfront runoff (Thomas and others, 1997). 

Storms that originate in the Pacific Ocean travel over the 

mountains and locally intensify in the plains area of the four 

corners region (Arizona, Utah, Colorado, and New Mexico). 

Regional thunderstorms develop over the mountains during 

early and late summer. The greatest monthly precipitation and 

localized areas of rainfall typically occur in July and August. 

Intense, convective midsummer storms that commonly are preceded by mild rainfall can produce severe flooding. 

Floods in mountainous regions generally are produced by 

snowmelt and rarely by rainfall on snowpack. Floods in the 

plains, plateaus, valleys, and deserts almost always are produced by rainfall. 

Analysis of Magnitude and Frequency of 

Peak Discharges 

Peak-discharge data collected at crest-stage gages and 

continuously recording gaging stations were used to estimate 

the magnitude and frequency of peak discharges using a logPearson Type III probability distribution (Interagency Advisory 

Committee on Water Data, 1982). The peak-discharge characteristics at the gaging stations were related to basin and climatic 

characteristics using generalized least-squares (GLS) regression analyses. 

Station Flood-FrequencyAnalysis 

Peak-discharge data at gaging stations consist of a period 

of gaged record through 1999 of annual peak discharges, 

referred to as the systematic record, and stations with one or 

more historic, extreme discharges outside the systematic record 

(Interagency Advisory Committee on Water Data, 1982). Relating the magnitudes of annual peak discharges, generally 

referred to as flood-frequency data or characteristics, to their 

expected frequency of exceedance is termed a flood-frequency 

analysis. The frequency of peak discharges generally is 

expressed in terms of exceedance probability or recurrence 

intervals. Exceedance probability is the probability that a flood 

will exceed a given magnitude in any year. Recurrence interval, 

in years, is the reciprocal of the exceedance probability. For 

example, a flood with an exceedance probability of 0.01 has a 

recurrence interval of 100 years. The term “recurrence interval” 

is used in this report for simplicity. 

Peak discharges for selected recurrence intervals were 

determined for each of 146 gaging stations using the logPearson Type III probability distribution as recommended by 

the Interagency Advisory Committee on Water Data (1982). 

Various adjustments for low outliers, zero-flow years, historic 

peak discharges, user-defined low-discharge threshold, and a 
4 Magnitude and Frequency of Peak Discharges for the Navajo Nation in Arizona, Utah, Colorado, and New Mexico 

user-defined generalized coefficient of skewness were applied 

to station data where applicable. 

Floods in the United States are derived mainly from four 

different mixed populations: rainfall, snowmelt runoff, rain on 

snowpack, from remnants of hurricanes or tropical storms. 

Some outliers existed in the annual peak-discharge series, 

which most likely was from a population other than the typical 

rainfall derived population; however an adequate number of 

annual peak-discharge data to define these rare populations was 

not recorded to date (1999) for any of the gaging stations in the 

study area. Annual peak discharges caused by annual snowmelt 

runoff from mountainous regions, annual peak discharges 

caused by annual rainfall runoff from convective thunderstorms 

are the most common, and annual peak discharges caused by 

annual rainfall runoff from infrequent remnants of hurricanes or 

tropical storms are the rare populations. Composite frequency 

analysis is required for some sites that have mixed populations. 

Crippen (1978) described techniques for making a composite 

analysis primarily from two populations of annual peak discharges, those caused by snowmelt runoff and rainfall runoff. 

The populations that cause floods were described in the 1988– 

89 National Water Summary (U.S. Geological Survey, 1991). 

Only a few gaging stations have recorded extreme peak discharges that plot as high outliers from the main distribution. 

Data on the separate sample populations for these rare storms 

are inadequate, thus a composite frequency analysis could not 

be performed. 

The low-discharge threshold was used in investigations 

of flood frequency in the southwestern United States by 

Waltemeyer (1996) and Thomas and others (1997). The userdefined low-discharge threshold is based on the rationale that, 

in some instances, discharges lessthan some threshold value are 

not from the same population of peak discharges as the larger 

peak discharges. A probability-density-function plot of annual 

series data indicates that these low discharges have a different 

slope than the larger peak discharges. As a result, the overall fit 

of the probability distribution is affected, and peak discharges 

for large recurrence intervals tend to be underestimated when 

the low discharges are included. The low-discharge threshold 

was visually selected from the probability-density-function 

plots and applied to the frequency analysis of 82 of the 146 gaging stations (four flood regions in appendix 1). Use of the lowdischarge threshold generally eliminated the peak discharges 

having a recurrence interval less than 1.4 years. 

The skew coefficient used in the log-Pearson Type III 

analysis is a weighted value determined by weighting the station skew with a generalized skew in inverse proportion to its 

mean-square errors (Interagency Advisory Committee on 

Water Data, 1982). In this report, a generalized skew is used 

based on research in prior investigations. The station skew used 

in an investigation in New Mexico (Waltemeyer, 1986) ranged 

from -0.22 to 0.29 log units for the physiographic regions; previous investigations have reported the median for most of the 

regions as close to zero (Waltemeyer, 1986). A recent investigation of flood frequency for the southwestern United States 

(Thomas and others, 1997) also used zero for the generalized 

skew. Results from the investigation indicated that the meansquare error of generalized skew was 0.31; the same meansquare error was considered to be applicable for the investigation described in this report. Accordingly, the generalized skew 

for the four flood regions (8, 11, high elevation, and 6) was considered to be zero for this investigation. 

The USGS computer program PEAKFQ (Kirby, 1981) 

was used to perform the flood-frequency analyses. Peakdischarge data and basin characteristics were determined from 

the NWISWeb (U.S. Geological Survey, 2001) and GIS (GIS 

Weasel) computerized systems (U.S. Geological Survey, 2000) 

and entered in the ANNIE data-management program (Lumb 

and others, 1990) for analysis. Selected basin, climatic, and 

flood characteristics for each station are listed in appendixes 1 

and 2. 

Regional Flood-Frequency Analysis 

Regionalization of flood-frequency characteristics with 

basin and climatic characteristics is mandated to estimate peak 

discharge at ungaged sites (New Mexico Department of Transportation, 1995). The magnitude of peak discharge is influenced 

by the basin and climatic characteristics of a physiographic 

region. In the western United States, Thomas and others (1997) 

identified two flood regions that have different flood characteristics (regions 8 and 11). These two flood regions, a region in 

New Mexico (region 6), and a high-elevation region (greater 

than 7,500 ft in elevation) were used for this report. Floods in 

regions 8, 11, and 6 are generally in response to rainfall runoff, 

whereas floods at elevations greater than 7,500 ft (highelevation region) are generally in response to snowmelt runoff 

(Jarrett and Costa, 1982). These regions generally correspond to 

the hydrologic unit code defined by the USGS (Seaber and 

others 1987). The regional equations developed for these four 

flood regions attempt to explain flood response with selected 

basin and climatic characteristics. Each region has unexplained 

variation, largely from basin and climatic characteristics that 

are not measured and used in the regional equations. 

Ordinary least-squares (OLS) regression techniques 

(Minitab, Inc., 2003) were used to determine the most appropriate basin and climatic variables. Generalized least-squares 

(GLS) regression analysis (Stedinger and Tasker, 1985) was 

used to determine the values of the regression constant, 

regression coefficients, and the error terms of the regression 

equations. 

Determination of Basin and Climatic Characteristics 

Regional equations commonly are used for estimating the 

magnitude and frequency of peak discharges at locations that 

have no streamflow data. Equations have been developed from 

a regression analysis that relate peak discharges for recurrence 

intervals determined at gaging stations to basin and climatic 

characteristics. 
5 

Geographical InformationSystem 

Basin and climatic characteristics were computed using an 

ARC/INFO geographical information system (GIS) (ESRI, 

1999) and algorithms in the GIS Weasel developed by the 

USGS (U.S. Geological Survey, 2000). The GIS Weasel uses a 

graphical-user interface based on the ARC/INFO, arc macro 

language (AML) scripts, and C++ programming language. The 

operation of the GIS Weasel does not require GIS expertise, but 

knowledge of ARC/INFO is helpful in changing the geographical projections from decimal degrees to other projections and 

in merging grids. The GIS Weasel online computer program 

(U.S. Geological Survey, 2000) was used to derive basin and 

climatic characteristics from raster data. The GIS Weasel uses a 

GRID subsystem of ARC/INFO to discretize coverages (vector 

data) into grids of cells with specific dimensions (for example, 

85 ft by 85 ft) and to assign a data value to each grid cell. The 

grid of data values represents some aspect of the discretized 

coverage, such as elevation or precipitation. The data values can 

be manipulated by applying mathematical operations to individual cells, to the whole grid, or by combining two or more grids. 

The GIS Weasel runs on a Unix or Windows NT platform and 

is available for downloading at http://wwwbrr.cr.usgs.gov/ 

weasel/, accessed July 10, 2000. Coverages of vector data were 

converted to raster data by discretizing coverages into a regularly spaced grid. The rasterization of the vector data or the 

use of raster data herein is referred to as “raster modeling.” 

Grid cells were assigned data values representing geospatial 

characteristics. 

Basin and Climatic Characteristics 

The following basin and climatic characteristics were 

determined with raster modeling by using GIS Weasel (appendix 2): average basin mean annual precipitation (1961–90), 

average basin mean winter precipitation (1961–90), average 

basin maximum 24-hour and 6-hour precipitation for 100-year 

recurrence interval using NOAA Atlas’s 2 (Miller and others, 

1973) and Atlas 14 (Bonnin and others, 2004), average basin 

slope, drainage area, average basin elevation, and average basin 

aspect. Existing basin and climatic characteristics also were 

available from the USGS Water-Data Storage and Retrieval 

System (WATSTORE) computerized data system (Dempster, 

1981; 1983). Existing data values for the basin and climatic 

characteristics were not used in the analysis because the only 

other significant characteristics in previous reports were average channel elevation and mean minimum January temperature. 

The average basin slope determined in this investigation was 

thought to be superior to average channel elevations and January temperature characteristic was considered to be an inherent 

characteristic in average basin elevation.

 The National Elevation Dataset (NED) is a USGS raster 

product (U.S. Geological Survey, 1999) designed to provide 

national elevation data in a seamless form with a consistent 

datum, elevation unit, and cartographic projection. Seamless 

means that all 7.5-min quadrangles for each State can be compiled into a single coverage or layer. Data corrections were 

Analysis of Magnitude and Frequency of Peak Discharges 

made in the NED assembly process to minimize artifacts, permit edge matching, and fill sliver areas of missing data. The 

NED has a resolution of 1 arc-second (approximately 30 m or 

91 ft) for the conterminous United States. For example, the New 

Mexico 7.5-min, 30-m NED actual cell size is 28 m (85 ft). In 

the NED assembly process, the elevation values were converted 

to decimal meters as a consistent unit of measure, the North 

American Datum (NAD) of 1983 consistently was used as a 

horizontal datum, and all data were recast in a geographic projection of decimal degrees. The web page describing the NED 

is available at http://edcnts12.cr.usgs.gov/ned/, accessed June 7, 

2006. 

The GIS Weasel (U.S. Geological Survey, 2000) aids in 

the preparation of spatial information for input to merged and 

distributed parameter physical-process models. GIS Weasel 

provides tools to delineate, characterize, modify, and parameterize “model response units” (MRU’s) within a geographical 

area; in this report, the area is the watershed or drainage area. 

An MRU in a watershed is typically used to represent an area 

that is characterized or attributed to estimate a uniform physical 

hydrologic process. Selected basin and climatic characteristics 

were computed for each watershed (average basin mean annual 

precipitation, average basin mean winter precipitation, average 

basin maximum 24-hour and 6-hour precipitation for 100-year 

recurrence interval using NOAA Atlas’s 2 (Miller and others, 

1973) and 14 (Bonnin and others, 2004), average basin slope, 

drainage area, average basin elevation, and average basin 

aspect) using a single MRU for each watershed. The 7.5-min 

digital elevation models (DEM’s) of the NED were used for 

Arizona, Utah, Colorado, and New Mexico. The mean annual 

and winter precipitation grids were composed for the fourcorner States. A point coverage (latitude and longitude) was 

developed for the gaging-station locations listed in appendix 1. 

Drainage area (DA), in square miles, typically is determined by planimetering the delineated area on the largest scale 

topographic maps available (generally the 7.5-min quadrangles, 

1:24,000-scale). In this investigation, DA was determined by 

raster modeling using 7.5-min, 30-m DEM’s. Average basin 

mean winter precipitation (Pw) and average basin mean annual 

precipitation (Pa) (1961–90, in inches) were averaged for each 

basin by raster modeling using a 4-km (2.5-mi) grid developed 

by Daly and others (1998) for Arizona, Utah, Colorado, and 

New Mexico. Average basin slope (S), in percent, was averaged 

for each basin by raster modeling using the grid cells of the 

7.5-min, 30-m DEM’s. Average basin aspect (A), in degrees 

from north, was averaged for each basin by raster modeling 

using the grid cells of the 7.5-min, 30-m DEM’s. Average basin 

elevation (E), in feet, was averaged for each basin by raster 

modeling using the grid cells of the 7.5-min, 30-m DEM’s. 

Estimates of mean monthly and mean annual precipitation 

for 1961–90 have been developed for 4-km (2.5-mi) grid cells 

by Daly and others (1998) for Arizona, Utah, Colorado, and 

New Mexico using the Parameter-Elevation Regressions on 

Independent Slopes Model (PRISM) presented by Daly and 

others (1994). PRISM estimates are based on all available point 

data, including the high-elevation precipitation data from the 
6 Magnitude and Frequency of Peak Discharges for the Navajo Nation in Arizona, Utah, Colorado, and New Mexico 

Natural Resources Conservation Service data collection, and a 

DEM to account for the effects of topography through station 

weighting and simple linear regression of precipitation and elevation. The mean monthly precipitation raster datasets are 

available at http://www.ocs.orst.edu/prism/prism_new.html, 

accessed November 15, 1999. The raster precipitation data units 

are in millimeters multiplied by 100, and the geographical coordinates of the grid cells are in decimal degrees. 

The mean monthly precipitation (1961–90) raster data 

were available only by month. By using the 12 monthly values 

of 30-year mean precipitation for each grid cell, the GRID subsystem of ARC/INFO was used to compute mean values for the 

annual 12-month period and for the 7-month winter period 

(October–April). GIS Weasel was used to compute an average, 

aerially weighted value for each basin from the values for the 

4-km (2.5-mi) grid cells within each basin. Finally, total values 

of precipitation for each period were computed and converted 

from millimeters to inches by multiplying by the number of 

months in the period (7 for the winter and 12 for the annual) and 

dividing by 2,540. 

Drainage area determined using GIS Weasel for the 62 

gaging stations in region 8 ranged from 0.06 to 4,350 mi2

; 

average basin slope ranged from 0.0231 to 0.4447 percent; and, 

average basin elevation ranged from 4,320 to 7,750 ft (table 1; 

appendix 1). Drainage area determined using GIS Weasel 

for the 34 gaging stations in region 11 ranged from 0.11 to 

2,150 mi2

; average basin slope ranged from 0.0177 to 0.1545 

percent (table 1; appendix 1); and, average basin elevation 

ranged from 5,010 to 7,440 ft (this variable was not significant 

in regression analysis; not listed in table 1 or appendix 1). 

Table 1. Range of statistically significant basin characteristics 

selected for use in the regression analysis. 

[--, indicates that characteristic is not statistically significant] 

Region 

Drainage 

area 

(square 

miles) 

Average 

basin 

slope 

(percent) 

Average 

basin 

elevation 

(feet) 

Region 8 0.06 to 

4,350 

0.0231 to 

0.4447 

4,320 to 1

7,750 

Region 11 0.11 to 

2,150 

0.0177 to 

0.1545 

--

Region high elevation 

(elevations greater than 

7,500 feet) 

1.7 to 

1,200 

-- --

Region 6 0.18 to 

7,220 

-- --

1Two gaging stations used at average basin elevation above 7,500 feet. 

Drainage area for the 27 gaging stations in region high elevation 

(elevations greater than 7,500 ft) ranged from 1.7 to 1,200 mi2 

(table 1; appendix 1); average basin slope ranged from 0.0851 

to 0.4130 percent (this variable was not significant in regression 

analysis; not listed in table 1 or appendix 1); and, average basin 

elevation ranged from 7,680 to 10,960 ft (this variable was not 

significant in regression analysis; not listed in table 1 or appendix 1). Drainage area for the 23 gaging stations in region 6 

ranged from 0.18 to 7,220 mi2 (table 1; appendix 1); average 

basin slope ranged from 0.0345 to 0.2096 percent (this variable 

was not significant in regression analysis; not listed in table 1 or 

appendix 1); and, average basin elevation ranged from 5,360 to 

7,260 ft (this variable was not significant in regression analysis; 

not listed in table 1 or appendix 1). Note that five gaging stations were outside the boundary of region 8 and 11, but nearby, 

because of the lack of data greater than 7,500 ft. 

A stepwise OLS multiple-regression procedure (Minitab, 

Inc., 2003) was used to determine which independent variables 

were significant in the equations for peak discharge. In the stepwise procedure, variables were added one at a time until all that 

were significant at the 5-percent level were included. Because 

the logarithms of peak discharge commonly are determined to 

be linearly related to logarithms of basin and climatic variables, 

all variables were transformed to base 10 logarithms for the 

regression analysis. The general form of the mathematical 

model is: 

log Qt = log k + a log x1 + b log x2 +. . .+ n log xn 

or Qt = K x1 

a x2 b . . . xn n (1) 

where 

Qt = peak discharge (instantaneous peak discharge), 

in cubic feet per second, for recurrence 

interval t; 

k = regression constant; 

a, b, ... n = regression coefficients; 

x1,x2, ... xn = basin and climatic variables; and 

K = the anti-log of the regression constant. 

One or more of the following basin and climatic characteristics was determined to be statistically significant for inclusion 

as independent variables in the regression equations: 

A drainage area, in square miles; 

S average basin slope upstream from the gaging station, in 

percent; and 

E average basin elevation, in feet above NAVD 88. 

Additional variables listed in appendix 2 also were determined using GIS, which include mean annual precipitation 

(1961–90), mean annual winter precipitation (1961–90), maximum 24-hour and 6-hour precipitation for 100-year recurrence 

intervals for NOAA Atlas 2 (Miller and others, 1973) and 

NOAA Atlas 14 (Bonnin and others, 2004), and average basin 

aspect. The maximum precipitation frequency from NOAA 

Atlas 2 was statistically significant in some flood regions in previous reports (Waltemeyer, 1986; 1996). Maximum precipitation characteristics from NOAA Atlas 2 and 14 were not statistically significant (p-value less than 5 percent). 
7 

Development of Generalized Least-Squares 

Regression Equations 

After the appropriate independent variables had been 

determined using the OLS regression, GLS regression was used 

to determine the best values of the regression coefficients. 

Regression coefficients determined from a GLS regression procedure (Stedinger and Tasker, 1985; Tasker and others, 1986) 

are considered to be better than those determined from OLS 

Analysis of Magnitude and Frequency of Peak Discharges 

regression because GLS regression considers the time-sampling 

error of the dependent variable, whereas OLS regression does 

not. GLS regression also considers cross correlation among 

concurrent peak discharges at gaging stations, whereas OLS 

regression does not. The basic regression model using GLS is 

shown as equation 1. The equations determined using GLS 

regression analysis are listed in table 2. Included are equations 

for estimating peak-discharge magnitudes that have recurrence 

intervals of 2, 5, 10, 25, 50, 100, and 500 years for each of the 

four regions in the Navajo Nation and surrounding region. 

Table 2. Regional flood-frequency equations using generalized least-squares regression. 

[Q, peak discharge, in cubic feet per second for indicated recurrence interval in years; A, drainage area, in square miles; S, average basin slope, in percent; 

E, average basin elevation, in feet; flood regions are listed in appendix 1] 

Flood-frequency 

equations 

Recurrence 

interval 

(years) 

Average standard error of estimates 

Regression Prediction 

Log units Percent Log units Percent 

Region 8 

Q2 = 1.08 X 107 A0.457 E-1.35 2 0.386 110 0.397 116 

Q5 = 1.71 X 1010 A0.372 S0.360 E-1.98 5 0.282 72 0.294 76 

Q10 = 8.79 X 1010 A0.343 S0.395 E-2.10 10 0.238 59 0.250 63 

Q25 = 3.91 X 1011 A0.310 S0.432 E-2.19 25 0.206 50 0.220 54 

Q50 = 8.47 X 1011 A0.287 S0.460 E-2.23 50 0.199 48 0.214 52 

Q100 = 1.53 X 1012 A0.265 S0.477 E-2.25 100 0.203 49 0.219 54 

Q500 = 4.24 X 1012 A0.224 S0.513 E-2.28 500 0.237 59 0.256 64 

Region 11 

Q2 = 3.05 X 102 A0.476 S0.608 2 0.348 95 0.367 102 

Q5 = 8.44 X 102 A0.471 S0.653 5 0.278 71 0.296 77 

Q10 = 1.49 X 103 A0.466 S0.688 10 0.262 66 0.280 72 

Q25 = 2.79 X 103 A0.460 S0.730 25 0.263 67 0.282 72 

Q50 = 4.19 X 103 A0.455 S0.759 50 0.274 70 0.295 77 

Q100 = 6.03 X 103 A0.450 S0.784 100 0.290 75 0.313 83 

Q500 = 1.25 X 104 A0.439 S0.836 500 0.336 91 0.363 101 

Region High Elevation (elevations greater than 7,500 feet above NAVD88) 

Q2 = 1.09 X 10 A0.767 2 0.199 48 0.208 51 

Q5 = 2.81 X 10 A0.711 5 0.158 38 0.168 40 

Q10 = 4.68 X 10 A0.680 10 0.149 36 0.160 38 

Q25 = 8.08 X 10 A0.646 25 0.152 36 0.164 39 

Q50 = 1.15 X 10 2 A0.623 50 0.160 38 0.173 41 

Q100 = 1.59 X 10 2 A0.602 100 0.172 41 0.186 45 

Q500 = 3.08 X 10 2 A0.557 500 0.205 50 0.222 55

 Region 6 

Q2 = 1.328 X 102 A0.420 2 0.376 98 0.390 111 

Q5 = 3.163 X 102 A0.394 5 0.298 80 0.307 81 

Q10 = 4.906 X 102 A0.383 10 0.269 66 0.277 71 

Q25 = 7.800 X 102 A0.372 25 0.252 62 0.260 66 

Q50 = 1.050 X 10 3 A0.365 50 0.248 61 0.256 64 

Q100 = 1.374 X 10 3 A0.359 100 0.251 61 0.260 66 

Q500 = 2.354 X 10 3 A0.345 500 0.273 68 0.284 73 
8 Magnitude and Frequency of Peak Discharges for the Navajo Nation in Arizona, Utah, Colorado, and New Mexico 

Improvement of Estimates at Gaging Stations 

Flood-frequency estimates for gaging stations having 

short-term records can be improved by weighting the station 

data with estimates from the regional regression equation 

(Interagency Advisory Committee on Water Data, 1982). The 

GLSNET (Regional Hydrologic Regression and Network 

Analysis using Generalized Least Squares) (Stedinger and 

Tasker, 1985) computer program computes the weighted 

estimate by using the observed station peak discharge, the 

regression-equation-predicted peak discharge, the equivalent 

years of record, and the actual record length. The observed (top 

line of data), predicted (middle line of data), and weighted (bottom line of data) flood-frequency data are listed in appendix 1 

for each gaging station. Weighted estimates, considered to be 

the best estimates at gaging stations, were determined by: 

Qw = (ni

 yi + eni xib) / (ni + eni) (2) 

where 

Qw = weighted flood-frequency data at the gaging station, in 

cubic feet per second; 

ni = actual record length, in years; 

yi = flood-frequency data at the gaging station, in cubic feet 

per second; 

eni = equivalent record length, in years; and 

xi

b = predicted flood-frequency data at the gaging station 

using the regression equation, in cubic feet per 

second. 

The weighted estimate determined by equation 2 is a function of actual record length and equivalent years from the 

regression analysis. If actual record length is longer than equivalent years, more weight is given to the observed station data. 

Conversely, if actual record length is shorter than equivalent 

years, more weight is given to the regression estimate. 

Limitations and Accuracy of Regression Equations 

The intended use of regression equations is to provide reliable estimates of peak discharges for selected recurrence intervals at unregulated, ungaged stream sites in the Navajo Nation 

and surrounding areas. Estimates commonly are required for 

ungaged sites on ungaged streams and, often, for ungaged sites 

on streams that have gaging stations located near the ungaged 

sites. Estimates at ungaged sites in a basin located in two 

regions are less common and somewhat more difficult than for 

basins in one region. In parts of some regions, regression equations may not be reliable for areas with sparse data or for 

ungaged sites that have basin and climatic variables beyond the 

range of those listed in table 1. The application of regional equations is not intended to preclude the use of sound hydrologic 

judgment or any other hydrologic or engineering method that 

may provide a more reliable estimate. Unit-hydrograph techniques that use gaged precipitation in a basin lacking gagingstation data may yield more reliable estimates of peak discharge 

than regional equations (Waltemeyer, 2002). 

Accuracy of the GLS regression equations generally is 

measured by the average standard error of prediction and the 

equivalent years of record. The average standard error of prediction is the sum of the average regression or model error and 

the average sampling error. The average standard error of 

regression presented in table 2 for a 100-year recurrence interval peak discharge ranged from 41 to 75 percent for the regions. 

The average standard error of prediction presented in table 2 for 

a 100-year recurrence interval peak discharge ranged from 45 to 

83 percent for the regions. Significant improvements over 

errors previously reported (Thomas and others, 1997) for 

regions 11, high elevation, and 6 are attributed to improved GIS 

determination of drainage area, average basin elevation, and the 

determination of average basin slope for the first time. Region 

8 in the 1997 investigation presented a regression analysis using 

drainage area and mean basin elevation with a standard error 

of prediction of 53 percent (average) for the 100-year flood. 

Region 11 presented a hybrid method indicating a large estimated standard error of prediction. No distinction of floods 

produced from a high-elevation region was presented. Overall, 

the equations based on GLS regression are considered to be 

more reliable than those in the previous report because of the 

increased length of record and improved GIS method. The average standard error of prediction was calculated in log units and 

converted to percent by using methods described by Hardison 

(1971). 

Equivalent years of record are an alternative measure of 

the accuracy of regression equations that are particularly useful 

for comparison to gaging-station data. Equivalent years of 

record are the number of years of actual peak-discharge record 

that would be required to achieve the same accuracy in the estimate of the t-year peak discharge as that obtained from the 

regional equation. Equivalent years of record are computed by 

the GLSNET computer program using the method described by 

Hardison (1971). 

Estimate of Magnitude and Frequency of Peak 

Discharges at Ungaged Sites

 Peak discharges that have various recurrence intervals can 

be estimated for ungaged sites on unregulated, ungaged streams 

from the regional equations listed in table 2. Gaging-station data 

can be extrapolated to estimate peak discharge at an ungaged 

site on a stream that has a nearby gaging station. Additionally, 

flood-frequency data are available for gaging stations on the 

main stems of some streams not used in this report for the development of regional regression relations. Data at these gaging 

stations can be used to make estimates at ungaged sites on 

the same stream. The independent variables that pertain to the 

equation for each region need to be measured as previously 

described for the development of the equations. These methods 

are described in more detail in the national handbook of recommended methods for water-data acquisition (U.S. Geological 

Survey, 1977) and in the section “Determination of Basin and 
Summary 9 

Climatic Characteristics” in this report. The following sections 

present examples of the above procedures. 

Ungaged Site on an Ungaged Stream 

An estimate of peak discharge with a recurrence interval of 

100 years is required for an ungaged site in region 8 that has a 

drainage area of 523 mi2

, average basin slope of 0.2422, in percent, and a mean basin elevation of 6,940 ft. Using the equation 

in table 2, the peak discharge for a 100-year recurrence interval 

is: 

Q100 = 1.53 x 1012 A0.265 S0.477 E-2.25

 = (1.53 x 1012) (523)0.265

 (0.2422)0.477 (6,940)

-2.25

 = 8,510 cubic feet per second. 

Ungaged Site on a Stream Having a Nearby Gaging 

Station 

Flood-frequency estimates can be made for ungaged sites 

upstream or downstream from gaging stations by using a 

method developed by Thomas and others (1997). This method 

transfers flood-frequency data at the gaging station to the 

ungaged site by using the following drainage-area ratio adjustment equation:

 QT(u) = QT(g) (Au/Ag)

x

, (3) 

where 

QT(u) = weighted flood-frequency estimate at the ungaged 

site, in cubic feet per second; 

QT(g) = flood-frequency estimate at the gaging station, in 

cubic feet per second; 

Au = drainage area at the ungaged site, in square miles; 

Ag = drainage area at the gaging station, in square miles; 

and 

x = exponent of the drainage area of the applicable 

regional regression equation listed in table 2. 

According to Saur (1974) the equation is applicable when 

the drainage-area ratio is between 0.5 and 1.5. For example, to 

estimate a 50-year peak discharge at an ungaged site in region 8 

upstream from gaging station Cisco Wash near Cisco, Utah 

(09163700), the station value listed in appendix 1 is 4,820 ft3

/s. 

Note that the weighted value of 5,770 ft

3

/s was not used because 

the technique makes a regional adjustment using the exponent 

from the regional equation. The weighted value is considered 

the best flood-frequency value, and this technique would make 

a double weight based on the regional flood information. The 

drainage area at the gaging station is 90.7 mi2

 (appendix 1). The 

exponent of the drainage area of the regression equation for a 

50-year recurrence interval for region 8 is 0.287 (table 2). The 

drainage area at the ungaged site is 75.5 mi2

, and using equation 

4 the peak discharge at the ungaged site is: 

Q50 u = Q50 g (Au/Ag)

x 

= (4,820) (75.5/90.7)

0.287 

= 4,580 cubic feet per second. (4) 

Summary 

Estimates of the magnitude and frequency of peak discharge are necessary for reliable flood-hazard mapping in the 

Navajo Nation in Arizona, Utah, Colorado, and New Mexico. 

The Bureau of Indian Affairs, U.S. Army Corps of Engineers, 

and Navajo Nation requested that the U.S. Geological Survey 

update estimates of peak discharge magnitude for gaging stations in the region and update regional equations for estimation 

of peak discharge and frequency at ungaged sites. 

Equations were developed for estimating the magnitude of 

peak discharges for recurrence intervals of 2, 5, 10, 25, 50, 100, 

and 500 years at ungaged sites using data collected through 

1999 at 146 gaging stations, an additional 13 years of peakdischarge data since the 1997 investigation (gaging-station data 

through 1986). Peak discharges for selected recurrence intervals were determined at gaging stations by fitting observed data 

to a log-Pearson Type III probability distribution with adjustments for a low-discharge threshold and a zero skew coefficient. A low-discharge threshold was applied to frequency 

analysis of 82 gaging stations. This application provides an 

improved fit of the log-Pearson Type III frequency distribution. 

Use of the low-discharge threshold generally eliminated the 

peak discharges having a recurrence interval of less than 

1.4 years in the probability-density function. 

The National Elevation Dataset (30-meter resolution) was 

used with the U.S. Geological Survey computer program USGS 

GIS Weasel for determining basin and climatic characteristics. 

Statistically significant characteristics are drainage area, average basin slope, and average basin elevation. Other characteristics not statistically significant but determined using GIS 

include average basin mean annual precipitation (1961–90), 

average basin mean annual winter precipitation (1961–90), 

average basin maximum 24-hour and 6-hour precipitation for 

100-year recurrence intervals for NOAA Atlas 2 and NOAA 

Atlas 14, and average basin aspect. 

The equations reflect flood response for four distinct flood 

regions with a distinction of flood response from high elevation 

in or near four regions. The flood regions were delineated on the 

basis of the hydrologic unit codes from the 1997 investigation 

and are: (1) region 8, (2) region 11, (3) region high elevation, 

and (4) region 6. Within each region, logarithms of the peak 

discharges for selected recurrence intervals were related to logarithms of basin and climatic characteristics using stepwise 

ordinary least-squares regression techniques for exploratory 

data analysis. Generalized least-squares regression techniques, 

an improved regression procedure that accounts for time and 

spatial sampling errors, then was applied to the same data used 

in the ordinary least-squares regression analyses. The average 

standard error of prediction for a peak discharge having a recurrence interval of 100 years for region 8 was 53 percent (average) from the 1997 investigation. Estimated standard error of 

prediction for a hybrid method for region 11 was large in the 

1997 investigation. Also, no distinction was made for floods 

produced from higher elevations. The average standard error of 
10 Magnitude and Frequency of Peak Discharges for the Navajo Nation in Arizona, Utah, Colorado, and New Mexico 

prediction, which includes average sampling error and average 

standard error of regression, ranged from 45 to 83 percent for 

the 100-year flood in this investigation. Overall, the equations 

based on generalized least squares regression techniques are 

considered to be more reliable than those in the 1997 investigation because of the increased length of record and improved GIS 

method. 

Techniques for transferring flood-frequency relations to 

ungaged sites on the same stream can be estimated at an 

ungaged site on a stream that has a gaging station upstream or 

downstream by using the drainage-area ratio and the drainagearea exponent from the regional regression equation of the 

respective region. 

References Cited 

Bonnin, G.M., Todd, D., Lin, B., Parzybok, T., Yekta, M., and 

Riley, D., 2004, Precipitation-frequency atlas of the western 

United States, volume 1—Semiarid Southwest (Arizona, 

Southeast California, Nevada, New Mexico, and Utah): 

National Oceanic and Atmospheric Administration NOAA 

Atlas 14, 246 p. 

Crippen, J.R., 1978, Composite log-Pearson Type III 

frequency-magnitude curve of annual floods: U.S. Geological Survey Open-File Report 78–352, 5 p. 

Daly, C., Neilson, R.P., and Phillips, D.L., 1994, A statisticaltopographic model for mapping climatological precipitation 

over mountainous terrain: Journal of Applied Meteorology. 

v. 33, p. 140–158. 

Daly, C., 1998, Arizona average monthly or annual precipitation, 1961–90: Water and climate Center of the Natural 

Resources Conservation Service, Portland Oreg., accessed 

August 16, 2000, at URL http://www.ocs.orst.edu/pub/maps/ 

Precipitation/Total/States/AZ. 

Daly, D., 1998, Colorado average monthly or annual precipitation, 1961–90: Water and climate Center of the Natural 

Resources Conservation Service, Portland Oreg., accessed 

August 16, 2000, at URL http://www.ocs.orst.edu/pub/maps/ 

Precipitation/Total/States/CO. 

Daly, D., 1998, New Mexico average monthly or annual precipitation, 1961–90: Water and climate Center of the Natural 

Resources Conservation Service, Portland Oreg., accessed 

August 16, 2000, at URL http://www.ocs.orst.edu/pub/maps/ 

Precipitation/Total/States/NM. 

Daly, D., 1998, Utah average monthly or annual precipitation, 

1961–90: Water and climate Center of the Natural Resources 

Conservation Service, Portland Oreg., accessed August 16, 

2000, at URL http://www.ocs.orst.edu/pub/maps/ 

Precipitation/Total/States/UT. 

Dempster, G.R., 1981, Peak flow file, chapter I, section B, 

WATSTORE user's guide: U.S. Geological Survey OpenFile Report 79–1336–I, v. 4, p. B-1 to B-58. 

Dempster, G.R., 1983, Streamflow basin characteristics, chapter II, section A, WATSTORE user's guide: U.S. Geological 

Survey Open-File Report 79–1336–I, v. 4, p. A-24 to A-34. 

ESRI, 1999, ARC/INFO version 8.0.1: Redlands, Calif., 

Environmental Systems Research Institute, variously paged. 

Hardison, C.H., 1971, Prediction error of regression estimates 

of streamflow characteristics at ungaged sites, in Geological 

Survey Research 1971: U.S. Geological Survey Professional 

Paper 750–C, p. C228–C236. 

Interagency Advisory Committee on Water Data, 1982, Guidelines for determining peak discharge frequency: Bulletin 17B 

of the Hydrology Subcommittee, Office of Water Data Coordination, U.S. Geological Survey, Reston, Va., 28 p. and 

appendices. 

Jarrett, R.D., and Costa, J.E., 1982, Multidisciplinary approach 

to the flood hydrology of foothill streams in Colorado, in

Proceedings, International Symposium of Hydrometerology: 

Denver, Colorado, American Water Resources Association, 

June 1982, p. 565–569. 

Kirby, W.H., 1981, Peak flow file, chapter I, section C, 

WATSTORE user’s guide: U.S. Geological Survey OpenFile Report 79–1336–I, v. 4, p. C-1 to C-57. 

Lumb, A.M., Kittle, J.L., Jr., and Flynn, K.M., 1990, User’s 

manual for ANNIE, a computer program for interactive 

hydrologic analyses and data management: U.S. Geological 

Survey Water-Resources Investigations Report 89–4080, 

236 p. 

Miller, J.F., Frederick, R.H., and Tracey, R.J., 1973, Precipitation-frequency atlas of the western United States, volume 

IV—New Mexico: National Oceanic and Atmospheric 

Administration NOAA Atlas 2, 43 p. 

Minitab, Inc., 2003, Meet Minitab-release 14 for Windows, 

2003: State College, Pa., p. 1–1 to 11–22. 

New Mexico Department of Transportation, 1995, Drainage 

Manual Volume 1, Hydrology: Preliminary Design 

Bureau/Drainage Section, NMDOT, Santa Fe, NM, 92 p. and 

appendices. 

Saur, V.B., 1974, Flood characteristics of Oklahoma Streams: 

U.S. Geological Survey Water-Resources Investigations 

Report 52–73, 301 p. 

Seaber, P.R., Kapinos, F.P., and Knapp., G.L., 1987, Hydrologic Unit Maps: U.S. Geological Survey Water-Supply 

Paper 2294, 63 p. 

Stedinger, J.R., and Tasker, G.D., 1985, Regional hydrologic 

analysis—Ordinary, weighted, and generalized least squares 

compared: Water Resources Research, v. 21, no. 9, 

p. 1,421–1,432. 

Tasker, G.D., Eychaner, J.H., and Stedinger, J.R., 1986, Application of generalized least-squares in regional hydrologic 

regression analysis: U.S. Geological Survey Water-Supply 

Paper 2310, p. 107–115. 

Thomas, B.E., Hjalmarson, H.W., and Waltemeyer, S.D., 1997, 

Methods for estimating magnitude and frequency of floods in 

the southwestern United States: U.S. Geological Survey 

Water Supply Paper 2433, 195 p. 

U.S. Geological Survey, 1977, National handbook of recommended methods for water-data acquisition: Chap. VII, 

Office of Water Data Coordination (rev. June 1978), p. 9–15. 
U.S. Geological Survey, 1991, National water summary 

1988–89—Hydrologic events and floods and droughts: U.S. 

Geological Survey Water-Supply Paper 2375, 591 p. 

U.S. Geological Survey, 1999, National elevation dataset 

(NED) online data: U.S. Geological Survey, EROS Data 

Center, edition 1, accessed July 10, 2000, at URL 

http://edcnts12.cr.usgs.gov/ned. 

U.S. Geological Survey, 2000, The GIS Weasel online data and 

program: U.S. Geological Survey, Branch of Regional 

Research, version 3.40, accessed July 10, 2000, at URL 

http://www.brr.cr.usgs/gov/weasel. 

U.S. Geological Survey, 2001, NWISWeb Data for the 

Nation—online data: U.S. Geological Survey, Reston, VA, 

accessed July 10, 2003, at URL http://waterdata.usgs.gov/. 

References Cited 11 

Waltemeyer, S.D., 1986, Techniques for estimating flood-flow 

frequency for unregulated streams in New Mexico: U.S. 

Geological Survey Water-Resources Investigations Report 

86–4104, 56 

Waltemeyer, S.D., 1996, Analysis of the magnitude and 

frequency of peak discharge and maximum observed peak 

discharge in New Mexico: U.S.Geological Survey WaterResources Investigations Report 96–4112, 79. 

Waltemeyer, S.D., 2002, Analysis of the magnitude and frequency of the 4-day annual low flow and regression equations for estimating the 4-day, 3-year low-flow frequency at 

ungaged sites on unregulated streams in New Mexico: U.S. 

Geological Survey Water-Resources Investigations Report 

01–4271, 22 p. 
Blank Page 
Magnitude and Frequency of Peak

Discharges for the Navajo Nation in 

Arizona, Utah, Colorado, and New 

Mexico

Appendix 1

Appendix 1—Selected Basin, Climatic, and 

Flood Characteristics, Maximum Peak 

Discharge Recorded, and Low-Discharge 

Threshold for Gaging Stations in Flood 

Regions 8, 11, High Elevation, and 6 
Appendix 1. Selected basin, climatic, and flood characteristics, maximum peak discharge recorded and low discharge threshold for 

14 Magnitude and Frequency of Peak Discharges for the Navajo Nation in Arizona, Utah, Colorado, and New Mexico 

Appendix 1. Selected basin, climatic, and flood characteristics, maximum peak discharge recorded and low ­-discharge threshold for 

[Peak discharge values in cubic feet per second: first line, station value used in regression analysis; second line, predicted value using regression equation; third 

previously published from manual delineation (Dempster, 1983). Blank basin slope or elevation indicates variable not statistically significant] 

Gagingstation 

number 

09163700 

Identifier 

(fig. 1) 

1 

Gaging-station 

name 

Region 8 

Cisco Wash near Cisco, Utah 

Drainage 

area 

(square 

miles) 

90.7 

29.0 

Average 

basin slope 

(percent) 

0.1241 

Average 

basin 

elevation 

(feet) 

4,820 

09181000 2 Onion Creek near Moab, Utah 20.2 

18.8 

0.3612 5,640 

09182600 3 Salt Wash near Thompson, Utah 1.43 

3.90 

0.0541 5,050 

09183000 4 Courthouse Wash near Moab, Utah 161 0.1224 4,770 

162 

09184000 5 Mill Creek near Moab, Utah 73.3 0.2709 7,060 

74.9 

09185200 6 Kane Springs Canyon near Moab, Utah 17.2 

17.8 

0.2167 6,270 

09185500 7 Hatch Wash near La Sal, Utah 366 0.0869 6,730 

378 

09187000 8 Cottonwood Creek near Monticello, Utah 113 0.3029 7,380 

115 

09314250 9 Price River below Miller Creek near Wellington, Utah 946 0.2490 7,660 

956 

09314280 10 Desert Seep Wash near Wellington, Utah 206 

191 

0.0613 5,750 

09314500 11 Price River at Woodside, Utah 1,730 

1,540 

0.2025 6,500 

09315200 12 Saleratus Wash tributary No. 2 near Woodside, Utah 4.92 

4.40 

0.1740 4,830 

09315900 13 Browns Wash tributary near Green River, Utah 3.04 

3.89 

0.0547 4,320 

09316000 14 Browns Wash near Green River, Utah 78.1 

75.0 

0.2154 5,030 
gaging stations in flood regions 8, 11, high elevation, and 6 Continued.

Appendix 1 15 

gaging stations in flood regions 8, 11, high elevation, and 6—Continued. 

line, weighted value with station and predicted value. --, no data; drainage area: first line determined from geographic information system analysis; second line, 

Gagingstation 

number 

Identifier 

(fig. 1) 

2 5 

Peak discharge (cubic feet per second) 

Recurrence interval (years) Maximum peak 

discharge 

recorded 10 25 50 100 500 

Lowdischarge 

threshold 

Record 

length 

(years) 

Region 8 

09163700 1 2,090 3,020 3,610 4,310 4,820 5,300 6,370 3,650 1,000 15 

943 2,210 3,470 5,580 7,490 9,700 16,200 -- -- --

2,000 2,890 3,580 4,720 5,770 6,920 9,690 -- -- --

09181000 2	 939 1,270 1,500 1,820 2,060 2,310 2,950 2,100 600 13 

512 1,360 2,280 3,940 5,590 7,610 14,000 -- -- -­

885 1,290 1,730 2,630 3,530 4,580 7,290 -- -- -­

09182600 3	 275 723 1,190 2,000 2,780 3,740 6,750 1,380 -- 15 

117 319 546 972 1,410 1,960 3,770 -- -- -­

255 615 931 1,440 1,960 2,630 4,890 -- -- -­

09183000 4 2,120 4,610 7,040 11,200 15,200 20,100 35,800 12,300 50 31 

1,220 2,780 4,300 6,780 8,980 11,500 18,800 -- -- --

2,090 4,470 6,660 10,200 13,400 17,400 30,300 -- -- --

09184000 5	 692 1,810 2,990 5,080 7,150 9,700 17,900 5,110 -- 46 

552 1,270 1,980 3,170 4,300 5,630 9,690 -- -- -­

689 1,780 2,880 4,720 6,470 8,620 15,700 -- -- -­

09185200 6	 541 826 1,030 1,320 1,540 1,780 2,370 1,290 200 15 

344 863 1,410 2,380 3,340 4,500 8,190 -- -- -­

522 833 1,130 1,700 2,250 2,900 4,590 -- -- -­

09185500 7	 505 1,190 1,910 3,220 4,550 6,260 12,200 4,650 100 22 

864 1,690 2,420 3,550 4,510 5,590 8,640 -- -- -­

512 1,220 1,960 3,280 4,540 6,080 11,100 -- -- -­

09187000 8	 390 1,270 2,330 4,410 6,650 9,570 19,900 2,200 -- 17 

635 1,420 2,180 3,460 4,640 6,030 10,200 -- -- -­

400 1,290 2,300 4,080 5,790 7,910 15,000 -- -- -­

09314250 9 1,720 2,360 2,760 3,230 3,580 3,900 4,640 2,880 -- 13 

1,390 2,710 3,880 5,650 7,180 8,880 13,600 -- -- --

1,710 2,390 2,930 3,800 4,540 5,310 6,990 -- -- --

09314280 10	 536 854 1,110 1,500 1,840 2,220 3,310 2,060 200 15 

806 1,640 2,410 3,600 4,640 5,790 9,090 -- -- -­

545 910 1,270 1,900 2,480 3,110 4,740 -- -- -­

09314500 11 4,460 6,490 7,870 9,620 10,900 12,200 15,300 11,200 3,000 49 

2,260 4,370 6,200 8,930 11,200 13,700 20,400 -- -- --

4,420 6,420 7,770 9,550 11,000 12,400 15,900 -- -- --

09315200 12 1,110 2,400 3,530 5,220 6,660 8,240 12,500 3,720 300 15 

299 839 1,450 2,600 3,770 5,240 10,000 -- -- -­

977 1,930 2,630 3,770 4,920 6,380 11,000 -- -- -­

09315900 13	 206 607 1,070 1,980 2,940 4,200 8,690 1,470 10 15 

213 577 985 1,740 2,490 3,410 6,410 -- -- -­

207 601 1,050 1,870 2,710 3,770 7,410 -- -- -­

09316000 14 1,790 3,750 5,460 8,090 10,400 13,000 20,100 5,620 -- 19 

961 2,340 3,750 6,160 8,390 11,000 18,900 -- -- --

1,730 3,540 5,050 7,400 9,570 12,100 19,600 -- -- --
16 Magnitude and Frequency of Peak Discharges for the Navajo Nation in Arizona, Utah, Colorado, and New Mexico 

Appendix 1. Selected basin, climatic, and flood characteristics, maximum peak discharge recorded and low-discharge threshold for 

Gagingstation 

number 

09327600 

Identifier 

(fig. 1) 

15 

Gaging-station 

name 

Region 8—Continued 

Ferron Creek tributary near Ferron, Utah 

Drainage 

area 

(square 

miles) 

0.62 

0.96 

Average 

basin slope 

(percent) 

0.0793 

Average 

basin 

elevation 

(feet) 

6,180 

09328300 16 Sids Draw near Castle Dale, Utah 18.4 

17.6 

0.1393 6,400 

09328600 17 Georges Draw near Hanksville, Utah 6.95 

6.63 

0.1126 6,940 

09328700 18 Temple Wash near Hanksville, Utah 44.2 

38.2 

0.0898 5,200 

09330120 19 Sulphur Creek near Fruita, Utah 54.0 

56.7 

0.2344 6,980 

09330200 20 Pleasant Creek at Notom, Utah 78.5 

80.6 

0.2334 7,400 

09330300 21 Neilson Wash near Caineville, Utah 22.5 

22.3 

0.0730 4,790 

09330400 22 Fremont River near Hanksville, Utah 1,900 

1,900 

0.1740 7,280 

09334000 23 North Wash near Hanksville, Utah 135 

136 

0.2501 5,120 

09336400 24 Upper Valley Creek near Escalante, Utah 53.9 

53.0 

0.2187 7,520 

09338900 25 Deer Creek near Boulder, Utah 65.4 

62.7 

0.2127 7,360 

09339200 26 Twentymile Wash near Escalante, Utah 144 

140 

0.2699 6,460 

09357200 27 Gallegos Canyon tributary near Nageezi, New Mexico 0.060 

0.200 

0.0231 6,650 

09357230 28 West Draw near Farmington, New Mexico 0.29 

0.32 

0.0491 5,980 
Appendix 1 17 

gaging stations in flood regions 8, 11, high elevation, and 6—Continued. 

Peak discharge (cubic feet per second) Gagingstation 

Identifier Recurrence interval (years) Maximum peak Low- Record 

(fig. 1) discharge discharge length number 2 5 10 25 50 100 500 recorded threshold (years) 

Region 8—Continued 

09327600 15 111 341 607 1,110 1,630 2,290 4,530 600 -- 12 

64 180 312 569 841 1,190 2,400 -- -- -­

104 289 467 774 1,100 1,520 3,020 -- -- -­

09328300 16	 464 1,300 2,120 3,450 4,630 5,970 9,620 2,150 170 14 

301 725 1,160 1,920 2,660 3,550 6,320 -- -- -­

450 1,180 1,810 2,730 3,580 4,600 7,780 -- -- -­

09328600 17	 210 587 1,010 1,830 2,690 3,800 7,750 1,650 10 15 

163 398 644 1,090 1,520 2,060 3,790 -- -- -­

206 548 890 1,470 2,040 2,770 5,320 -- -- -­

09328700 18	 139 381 671 1,270 1,940 2,890 6,680 1,880 30 10 

555 1,290 2,040 3,290 4,440 5,790 9,850 -- -- -­

159 494 976 2,010 3,060 4,330 8,400 -- -- -­

09330120 19	 688 1,310 1,860 2,700 3,450 4,300 6,790 2,600 350 16 

475 1,100 1,720 2,780 3,780 4,980 8,620 -- -- -­

671 1,280 1,820 2,730 3,600 4,620 7,640 -- -- -­

09330200 20	 238 793 1,470 2,800 4,220 6,080 12,600 2,040 -- 14 

502 1,120 1,730 2,740 3,690 4,810 8,190 -- -- -­

250 837 1,530 2,780 3,970 5,430 10,200 -- -- -­

09330300 21 1,140 2,250 3,220 4,720 6,050 7,550 11,800 5,450 350 15 

453 1,100 1,770 2,920 4,000 5,280 9,190 -- -- --

1,070 2,030 2,780 3,950 5,050 6,390 10,500 -- -- --

09330400 22 4,510 7,050 9,050 12,000 14,400 17,100 24,700 15,300 2,000 15 

1,850 3,420 4,760 6,720 8,340 10,100 14,900 -- -- --

4,390 6,660 8,280 10,500 12,400 14,600 21,100 -- -- --

09334000 23 1,180 3,070 5,010 8,420 11,700 15,800 28,500 8,900 -- 21 

1,230 2,920 4,630 7,480 10,100 13,100 22,200 -- -- --

1,180 3,050 4,940 8,140 11,100 14,700 25,900 -- -- --

09336400 24	 719 1,580 2,440 3,950 5,440 7,320 13,600 5,560 -- 16 

409 925 1,430 2,290 3,100 4,070 7,020 -- -- -­

696 1,470 2,170 3,280 4,340 5,660 10,100 -- -- -­

09338900 25	 392 1,250 2,290 4,370 6,630 9,650 20,600 3,820 50 16 

457 1,030 1,580 2,520 3,400 4,440 7,590 -- -- -­

396 1,210 2,100 3,570 4,960 6,720 12,800 -- -- -­

09339200 26 1,750 2,910 3,820 5,100 6,210 7,390 10,600 4,620 1,000 10 

859 1,940 3,000 4,740 6,350 8,210 13,800 -- -- --

1,650 2,690 3,540 4,950 6,280 7,830 12,200 -- -- --

09357200 27 108 205 291 425 546 686 1,100 580 25 35 

15 42 74 138 209 303 641 -- -- -­

94 160 206 281 364 475 858 -- -- -­

09357230 28	 23 38 49 64 76 88 119 54 -- 21 

43 122 213 393 585 837 1,710 -- -- -­

24 47 77 143 214 296 510 -- -- -­
18 Magnitude and Frequency of Peak Discharges for the Navajo Nation in Arizona, Utah, Colorado, and New Mexico 

Appendix 1. Selected basin, climatic, and flood characteristics, maximum peak discharge recorded and low-discharge threshold for 

Gagingstation 

number 

09367530 

Identifier 

(fig. 1) 

29 

Gaging-station 

name 

Region 8—Continued 

Locke Arroyo near Kirtland, New Mexico 

Drainage 

area 

(square 

miles) 

2.68 

2.96 

Average 

basin slope 

(percent) 

0.0720 

Average 

basin 

elevation 

(feet) 

5,500 

09367550 30 Stevens Arroyo near Kirtland, New Mexico 4.72 

4.59 

0.0569 5,490 

09367561 31 Shumway Arroyo near Waterflow, New Mexico 134 

73.8 

0.1109 5,640 

09367860 32 Chusca Wash near Mexican Springs, New Mexico 9.78 

8.70 

0.1922 7,240 

09367900 33 Black springs Wash near Mexican Springs, New Mexico 7.13 

7.05 

0.1513 6,690 

09367930 34 Hunter Wash at Bisti Trading Post, New Mexico 45.0 

45.6 

0.0494 6,200 

09367950 35 Chaco River near Waterflow, New Mexico 4,350 

4,350 

0.0681 6,290 

09367980 36 Rattlesnake Arroyo near Shiprock, New Mexico 21.3 

--

0.0317 5,230 

09368020 37 Malpais Arroyo near Shiprock, New Mexico 2.02 

--

0.0567 5,330 

09371000 38 Mancos River near Towaoc, Colorado 523 

526 

0.2422 6,940 

09378480 39 Montezuma Creek near Monticello, Utah 142 

117 

0.1209 7,030 

09378950 40 Comb Wash near Blanding, Utah 10.3 

10.3 

0.2549 5,810 

09379000 41 Comb Wash near Bluff, Utah 276 0.2009 5,880 

278 

09379030 42 Black Mountain Wash near Chinle, Arizona 73.5 0.1031 5,830 

80.7 
Appendix 1 19 

gaging stations in flood regions 8, 11, high elevation, and 6—Continued. 

Peak discharge (cubic feet per second) Gagingstation 

Identifier Recurrence interval (years) Maximum peak Low- Record 

(fig. 1) discharge discharge length number 2 5 10 25 50 100 500 recorded threshold (years) 

Region 8—Continued 

09367530 29 94 248 408 684 949 1,270 2,260 535 -- 35 

143 377 634 1,110 1,590 2,190 4,140 -- -- -­

95 259 441 785 1,130 1,550 2,840 -- -- -­

09367550 30	 134 470 901 1,800 2,800 4,160 9,250 1,550 10 21 

171 429 704 1,200 1,680 2,280 4,180 -- -- -­

136 464 853 1,570 2,280 3,210 6,530 -- -- -­

09367561 31	 183 783 1,680 3,820 6,500 10,500 27,800 6,420 10 16 

821 1,800 2,730 4,250 5,610 7,160 11,700 -- -- -­

197 861 1,850 3,950 6,150 8,990 19,500 -- -- -­

09367860 32 1,260 2,430 3,470 5,130 6,650 8,430 13,800 6,400 600 29 

203 504 819 1,390 1,950 2,650 4,890 -- -- --

1,150 2,020 2,610 3,420 4,240 5,310 9,060 -- -- --

09367900 33	 446 1,000 1,530 2,430 3,270 4,280 7,390 2,250 -- 44 

191 481 789 1,350 1,910 2,600 4,820 -- -- -­

428 919 1,340 2,020 2,680 3,500 6,210 -- -- -­

09367930 34	 752 1,200 1,510 1,900 2,200 2,500 3,190 1,570 -- 18 

348 742 1,120 1,740 2,300 2,950 4,880 -- -- -­

730 1,140 1,430 1,860 2,230 2,640 3,700 -- -- -­

09367950 35 3,880 5,270 6,190 7,350 8,220 9,090 11,100 7,300 2,500 30 

2,610 4,440 5,930 7,980 9,540 11,200 15,500 -- -- --

3,870 5,250 6,180 7,410 8,360 9,330 11,600 -- -- --

09367980 36	 143 568 1,230 2,900 5,150 8,780 26,900 3,800 -- 17 

300 670 1,040 1,650 2,210 2,870 4,840 -- -- -­

149 579 1,190 2,440 3,790 5,660 13,600 -- -- -­

09368020 37 57 127 194 307 412 539 932 321 -- 16 

125 331 559 981 1,410 1,940 3,690 -- -- -­

63 160 288 558 840 1,180 2,180 -- -- -­

09371000 38 1,110 1,920 2,570 3,510 4,300 5,150 7,450 5,300 60 66 

1,270 2,620 3,850 5,770 7,450 9,350 14,800 -- -- --

1,110 1,940 2,620 3,660 4,560 5,530 8,090 -- -- --

09378480 39	 475 1,140 1,790 2,900 3,960 5,240 9,220 1,720 -- 10 

587 1,220 1,820 2,770 3,630 4,610 7,500 -- -- -­

486 1,160 1,800 2,840 3,770 4,850 8,110 -- -- -­

09378950 40	 746 1,440 2,090 3,150 4,150 5,350 9,160 3,430 100 10 

330 879 1,480 2,580 3,680 5,040 9,440 -- -- -­

673 1,260 1,810 2,820 3,850 5,150 9,340 -- -- -­

09379000 41 1,760 3,160 4,410 6,400 8,230 10,400 17,100 8,390 1,150 10 

1,230 2,680 4,060 6,280 8,240 10,500 17,000 -- -- --

1,710 3,070 4,300 6,350 8,240 10,400 17,000 -- -- --

09379030 42	 892 1,630 2,220 3,060 3,760 4,510 6,480 3,100 450 15 

588 1,310 2,020 3,180 4,240 5,470 9,130 -- -- -­

871 1,580 2,170 3,100 3,950 4,910 7,540 -- -- -­
20 Magnitude and Frequency of Peak Discharges for the Navajo Nation in Arizona, Utah, Colorado, and New Mexico 

Appendix 1. Selected basin, climatic, and flood characteristics, maximum peak discharge recorded and low-discharge threshold for 

Gagingstation 

number 

09379060 

Identifier 

(fig. 1) 

43 

Gaging-station 

name 

Region 8—Continued 

Lukachukai Creek tributary near Lukachukai, Arizona 

Drainage 

area 

(square 

miles) 

1.36 

1.37 

Average 

basin slope 

(percent) 

0.0319 

Average 

basin 

elevation 

(feet) 

5,830 

09379300 44 Lime Creek near Mexican Hat, Utah 65.2 

32.0 

0.1831 5,190 

09379560 45 El Capitan Wash near Kayenta, Arizona 6.07 

5.88 

0.1348 5,620 

09379800 46 Coyote Creek near Kanab, Utah 89.6 

89.0 

0.1508 4,830 

09379820 47 Buck Tank Draw near Kanab, Utah 4.81 

5.25 

0.0785 5,100 

09381800 48 Paria River near Kanab, Utah 642 0.2335 6,260 

647 

09382000 49 Paria River at Lees Ferry, Arizona 1,060 

1,410 

0.1874 6,170 

09403780 50 Kanab Creek near Fredonia, Arizona 1,080 

1,080 

0.1294 5,870 

09403800 51 Bitter Seeps Wash tributary near Fredonia, Arizona 2.48 

2.85 

0.2243 5,050 

09404500 52 Mineral Gulch near Mount Carmel, Utah 8.26 

7.60 

0.1297 5,960 

09404900 53 East Fork Virgin River near Springdale, Utah 339 0.2449 6,180 

343 

09405420 54 North Fork Virgin River below Bulloch Canyon near Glendale, Utah 29.4 

29.6 

0.3130 7,750 

09406300 55 Kanarra Creek at Kanarraville, Utah 9.74 

9.85 

0.3537 7,720 

09406700 56 South Ash Creek below Mill Creek near Pintura, Utah 11.0 

11.0 

0.4447 6,840 
Appendix 1 21 

gaging stations in flood regions 8, 11, high elevation, and 6—Continued. 

Peak discharge (cubic feet per second) Gagingstation 

Identifier Recurrence interval (years) Maximum peak Low- Record 

(fig. 1) discharge discharge length number 2 5 10 25 50 100 500 recorded threshold (years) 

Region 8—Continued 

09379060 43	 20 46 74 126 182 255 522 49 12 14 

77 195 322 557 792 1,090 2,050 -- -- -­

23 61 117 245 384 557 1,100 -- -- -­

09379300 44 1,680 4,150 6,560 10,500 14,200 18,600 31,400 6,600 100 15 

804 1,940 3,100 5,070 6,900 9,060 15,600 -- -- --

1,600 3,700 5,430 7,980 10,300 13,200 22,300 -- -- --

09379560 45	 469 950 1,390 2,110 2,780 3,570 5,980 2,340 -- 14 

233 613 1,030 1,790 2,550 3,490 6,520 -- -- -­

440 869 1,260 1,950 2,650 3,520 6,290 -- -- -­

09379800 46 1,410 2,740 3,850 5,490 6,870 8,390 12,500 4,590 100 14 

985 2,340 3,700 5,990 8,080 10,500 17,700 -- -- --

1,370 2,680 3,810 5,670 7,380 9,330 14,700 -- -- --

09379820 47 10 70 208 685 1,510 3,100 13,900 680 -- 10 

215 561 939 1,630 2,310 3,150 5,860 -- -- -­

14 124 387 1,110 1,970 3,140 7,860 -- -- -­

09381800 48 2,480 5,290 7,960 12,400 16,600 21,700 37,600 15,400 -- 17 

1,650 3,420 5,050 7,590 9,780 12,200 19,200 -- -- --

2,430 5,050 7,310 10,700 13,800 17,400 28,900 -- -- --

09382000 49 3,450 6,320 8,750 12,500 15,700 19,400 29,900 16,100 1,000 76 

1,970 3,920 5,670 8,320 10,500 13,000 19,800 -- -- --

3,430 6,260 8,610 12,100 15,200 18,600 28,700 -- -- --

09403780 50 871 1,780 2,620 3,970 5,220 6,700 11,200 4,630 100 16 

1,950 3,820 5,470 7,950 10,000 12,200 18,400 -- -- -­

896 1,900 2,920 4,690 6,310 8,130 13,200 -- -- -­

09403800 51	 129 560 1,190 2,640 4,380 6,890 17,000 1,950 -- 14 

222 652 1,160 2,130 3,150 4,460 8,850 -- -- -­

139 586 1,180 2,330 3,550 5,160 11,000 -- -- -­

09404500 52	 315 931 1,650 3,050 4,540 6,500 13,500 3,210 30 14 

238 604 995 1,700 2,400 3,250 5,990 -- -- -­

307 857 1,410 2,340 3,260 4,440 8,590 -- -- -­

09404900 53 1,050 2,600 4,110 6,590 8,880 11,600 19,400 3,540 -- 8 

1,300 2,820 4,240 6,530 8,560 10,900 17,500 -- -- --

1,070 2,640 4,150 6,570 8,730 11,200 18,400 -- -- --

09405420 54	 203 406 603 943 1,280 1,690 3,090 1,740 -- 11 

331 791 1,260 2,070 2,870 3,840 6,880 -- -- -­

212 465 765 1,360 1,960 2,680 4,860 -- -- -­

09406300 55	 141 367 608 1,050 1,490 2,050 3,920 1,000 -- 23 

216 552 910 1,570 2,230 3,060 5,770 -- -- -­

145 387 663 1,190 1,740 2,420 4,620 -- -- -­

09406700 56	 219 523 839 1,410 1,980 2,700 5,160 1,910 60 

299 797 1,340 2,340 3,360 4,630 8,780 -- -- -­

225 566 966 1,760 2,580 3,600 6,870 -- -- -­

16 
22 Magnitude and Frequency of Peak Discharges for the Navajo Nation in Arizona, Utah, Colorado, and New Mexico 

Appendix 1. Selected basin, climatic, and flood characteristics, maximum peak discharge recorded and low-discharge threshold for 

Gagingstation 

number 

09406800 

Identifier 

(fig. 1) 

57 

Gaging-station 

name 

Region 8—Continued 

South Ash Creek near Pintura, Utah 

Drainage 

area 

(square 

miles) 

13.7 

14.0 

Average 

basin slope 

(percent) 

0.4152 

Average 

basin 

elevation 

(feet) 

6,590 

09407200 58 Ash Creek below West Field Ditch at Toquerville, Utah 200 

201 

0.2998 5,920 

09408000 59 Leeds Creek near Leeds, Utah 15.3 

15.5 

0.3708 6,130 

09408150 60 Virgin River near Hurricane, Utah 700 

1,490 

0.2830 5,250 

09409100 61 Santa Clara River above Baker Reservoir near Central, Utah 111 0.2783 7,230 

116 

09409500 62 Moody Wash near Veyo, Utah 33.5 

33.0 

0.2953 6,010 

09385800 63 

Region 11 

Little Colorado River tributary near St. Johns, Arizona 0.35 

0.35 

0.0985 

09386200 64 Carrizo Creek near Salt Lake, New Mexico 1,820 

560 

0.0827 

09386950 65 Zuni River above Black Rock Reservoir, New Mexico 831 0.0874 

848 

09387050 66 Galestena Canyon tributary near Black Rock, New Mexico 18.5 

19.0 

0.0729 

09390500 67 Show Low Creek near Lakeside, Arizona 67.9 

68.6 

0.0579 

09395100 68 Carr Lake Draw tributary near Holbrook, Arizona 1.16 

1.28 

0.0298 

09395200 69 Decker Wash near Snowflake, Arizona 15.8 

16.5 

0.0640 

09395500 70 Puerco River at Gallup, New Mexico 548 0.1106 

558 
Appendix 1 23 

gaging stations in flood regions 8, 11, high elevation, and 6—Continued. 

Peak discharge (cubic feet per second) Gagingstation 

Identifier Recurrence interval (years) Maximum peak Low- Record 

(fig. 1) discharge discharge length number 2 5 10 25 50 100 500 recorded threshold (years) 

Region 8—Continued 

09406800 57	 194 468 739 1,190 1,630 2,140 3,710 938 -- 14 

344 908 1,520 2,640 3,770 5,170 9,690 -- -- -­

204 537 934 1,730 2,540 3,510 6,400 -- -- -­

09407200 58 265 829 1,480 2,730 4,030 5,700 11,400 1,850 -- 10 

1,190 2,710 4,200 6,650 8,890 11,500 19,100 -- -- -­

302 1,040 2,050 4,080 6,060 8,370 15,200 -- -- -­

09408000 59	 182 747 1,560 3,440 5,710 9,020 22,800 4,420 -- 36 

396 1,050 1,760 3,050 4,340 5,930 11,100 -- -- -­

187 769 1,590 3,340 5,270 7,890 18,000 -- -- -­

09408150 60 5,380 8,460 11,000 14,700 18,000 21,700 32,300 66,000 3,000 32 

2,450 5,370 8,110 12,400 16,200 20,400 32,200 -- -- --

5,290 8,260 10,700 14,300 17,600 21,400 32,300 -- -- --

09409100 61 64 285 604 1,310 2,140 3,300 7,720 1,160 38 10 

637 1,430 2,190 3,470 4,650 6,040 10,200 -- -- -­

76 371 854 1,940 3,080 4,470 8,900 -- -- -­

09409500 62	 208 800 1,610 3,360 5,380 8,220 19,200 1,810 -- 15 

537 1,350 2,190 3,680 5,110 6,850 12,300 -- -- -­

224 875 1,750 3,480 5,250 7,480 15,200 -- -- -­

Region 11 

09385800 63	 51 126 205 352 503 697 1,380 326 -- 14 

45 113 186 317 448 610 1,140 -- -- -­

51 124 201 341 484 666 1,290 -- -- -­

09386200 64 329 1,260 2,490 5,110 8,070 12,130 27,300 8,380 250 38 

2,380 5,700 8,920 14,300 19,210 25,000 42,000 -- -- -­

353 1,400 2,840 5,870 9,190 13,600 29,300 -- -- -­

09386950 65 673 1,970 3,270 5,420 7,360 9,570 15,700 5,200 540 30 

1,690 4,070 6,410 10,300 14,000 18,300 31,100 -- -- -­

700 2,090 3,550 5,990 8,220 10,800 17,800 -- -- -­

09387050 66 86 192 299 487 672 904 1,670 593 -- 41 

249 603 962 1,580 2,170 2,870 5,050 -- -- -­

89 208 335 566 794 1,070 1,980 -- -- -­

09390500 67	 342 1,410 2,910 6,190 9,980 15,300 35,500 5,550 -- 46 

401 958 1,510 2,420 3,290 4,300 7,370 -- -- -­

343 1,380 2,760 5,590 8,740 13,000 29,000 -- -- -­

09395100 68	 27 73 120 198 271 356 606 140 -- 13 

39 91 143 230 312 410 710 -- -- -­

28 76 125 208 284 374 641 -- -- -­

09395200 69 52 212 448 1,010 1,710 2,750 7,350 1,170 -- 14 

213 515 817 1,330 1,830 2,420 4,230 -- -- -­

62 257 535 1,120 1,750 2,610 5,840 -- -- -­

09395500 70 1,390 4,640 8,170 14,200 19,900 26,400 45,000 12,000 -- 41 

1,610 3,910 6,220 10,200 13,900 18,300 31,600 -- -- --

1,400 4,590 7,960 13,700 18,900 25,100 42,700 -- -- --
24 Magnitude and Frequency of Peak Discharges for the Navajo Nation in Arizona, Utah, Colorado, and New Mexico 

Appendix 1. Selected basin, climatic, and flood characteristics, maximum peak discharge recorded and low-discharge threshold for 

Gagingstation 

number 

Identifier 

(fig. 1) 

Gaging-station 

name 

Drainage 

area 

(square 

miles) 

Average 

basin slope 

(percent) 

Average 

basin 

elevation 

(feet) 

Region 11—Continued 

09395600 71 Wagon Trail Wash near Gamerco, New Mexico 0.28 0.0451 

0.38 

09395900 72 Black Creek near Lupton, Arizona 491 0.1188 

493 

09396100 73 Puerco River near Chambers, Arizona 2,150 0.0976 

2,160 

09396400 74 Dead Wash tributary near Holbrook, Arizona 0.75 

1.22 

0.0653 

09397100 75 Leroux Wash near Holbrook, Arizona 806 0.0471 

809 

09397500 76 Chevelon Fork below Wildcat Canyon, near Winslow, Arizona 270 

275 

0.1132 

09397800 77 Brookbank Canyon near Heber, Arizona 27.5 

27.9 

0.0802 

09398000 78 Chevlon Creek near Winslow, Arizona 983 

781 

0.0686 

09398500 79 Clear Creek below Willow Creek near Winslow, Arizona 316 0.1533 

317 

09400100 80 Ganado Wash tributary near Ganado, Arizona 8.89 

7.85 

0.0379 

09400200 81 Steamboat Wash tributary near Ganado, Arizona 0.156 

0.320 

0.0863 

09400290 82 Teshbito Wash tributary near Holbrook, Arizona 19.8 

20.0 

0.0675 

09400300 83 Teshbito Wash near Holbrook, Arizona 68.0 

60.3 

0.0690 

09400530 84 Cow Canyon near Winslow, Arizona 6.25 

7.53 

0.0177 
Appendix 1 25 

gaging stations in flood regions 8, 11, high elevation, and 6—Continued. 

Peak discharge (cubic feet per second) Gagingstation 

Identifier Recurrence interval (years) Maximum peak Low- Record 

(fig. 1) discharge discharge length number 2 5 10 25 50 100 500 recorded threshold (years) 

Region 11—Continued 

09395600 71	 78 170 255 393 520 668 1,110 437 20 24 

25 61 98 162 224 299 538 -- -­

74 154 224 336 442 568 955 -- -­

09395900 72 2,650 4,360 5,670 7,500 8,980 10,600 14,700 7,680 1,000 19 

1,590 3,890 6,210 10,200 13,900 18,400 32,000 -- -- --

2,560 4,300 5,760 8,050 10,000 12,300 18,200 -- -- --

09396100 73 6,090 10,600 14,000 18,600 22,300 26,100 35,600 17,800 2,100 28 

2,850 6,870 10,800 17,400 23,500 30,700 51,900 -- -- --

5,890 10,200 13,500 18,400 22,500 26,900 38,300 -- -- --

09396400 74 202 373 515 730 917 1,130 1,710 743 100 13 

51 124 200 334 464 623 1,130 -- -- -­

177 307 409 576 733 920 1,480 -- -- -­

09397100 75 4,700 6,130 7,090 8,300 9,210 10,100 12,300 8,460 3,000 14 

1,150 2,690 4,140 6,500 8,650 11,100 18,400 -- -- --

4,220 5,450 6,360 7,800 9,050 10,400 13,900 -- -- --

09397500 76 2,220 6,460 11,400 20,800 30,700 43,800 89,700 24,700 -- 41 

1,160 2,850 4,540 7,460 10,200 13,600 23,600 -- -- --

2,170 6,130 10,400 18,300 26,400 36,900 73,600 -- -- --

09397800 77	 153 306 439 642 821 1,020 1,590 666 80 13 

318 774 1,240 2,030 2,790 3,700 6,510 -- -- -­

164 363 569 922 1,240 1,610 2,640 -- -- -­

09398000 78 2,470 6,370 10,800 19,500 28,900 41,600 89,700 33,600 550 49 

1,590 3,770 5,880 9,370 12,600 16,400 27,400 -- -- --

2,450 6,210 10,300 18,200 26,500 37,500 78,300 -- -- --

09398500 79 2,420 7,180 12,500 22,400 32,500 45,300 87,500 29,100 -- 45 

1,510 3,740 6,030 10,000 13,800 18,500 32,600 -- -- --

2,390 6,910 11,800 20,500 29,200 40,200 76,600 -- -- --

09400100 80	 240 525 801 1,270 1,710 2,250 3,970 1,680 40 14 

118 279 436 699 945 1,240 2,120 -- -- -­

226 474 699 1,070 1,430 1,860 3,240 -- -- -­

09400200 81	 47 163 311 619 966 1,440 3,240 383 10 14 

28 71 116 199 281 383 716 -- -- -­

45 140 245 441 648 924 1,930 -- -- -­

09400290 82	 611 758 843 940 1,010 1,070 1,200 890 400 15 

245 593 942 1,540 2,110 2,790 4,880 -- -- -­

563 727 865 1,090 1,270 1,470 1,930 -- -- -­

09400300 83	 663 1,040 1,320 1,680 1,970 2,260 2,990 1,580 400 14 

447 1,080 1,700 2,760 3,760 4,940 8,540 -- -- -­

640 1,050 1,400 1,940 2,410 2,920 4,250 -- -- -­

09400530 84	 65 127 179 255 318 388 575 253 30 

63 143 219 341 452 581 961 -- -- -­

65 129 185 271 346 429 655 -- -- -­

15 
26 Magnitude and Frequency of Peak Discharges for the Navajo Nation in Arizona, Utah, Colorado, and New Mexico 

Appendix 1. Selected basin, climatic, and flood characteristics, maximum peak discharge recorded and low-discharge threshold for 

Gagingstation 

number 

09400560 

Identifier 

(fig. 1) 

85 

Gaging-station 

name 

Region 11—Continued 

Oraibi Wash tributary near Oraibi, Arizona 

Drainage 

area 

(square 

miles) 

1.76 

1.78 

Average 

basin slope 

(percent) 

0.1545 

Average 

basin 

elevation 

(feet) 

09400565 86 Polacca Wash tributary near Chinle, Arizona 6.33 

6.45 

0.1236 

09400580 87 Castle Butte Wash near Winslow, Arizona 5.16 

5.57 

0.0726 

09400650 88 Sinclair Wash at Flagstaff, Arizona 7.44 

8.11 

0.0884 

09401220 89 Cedar Wash near Cameron, Arizona 558 0.0744 

579 

09401245 90 Klethla Valley tributary near Kayenta, Arizona 0.80 

0.79 

0.1247 

09401260 91 Moenkopi Wash at Moenkopi, Arizona 1,590 

1,630 

0.0955 

09404050 92 Spring Valley Wash tributary near Williams, Arizona 2.51 

5.00 

0.0320 

09404310 93 Yampai Canyon tributary near Peach Springs, Arizona 0.11 

0.20 

0.0833 

09502800 94 Williamson Valley Wash near Paulden, Arizona 253 

255 

0.1196 

09503800 95 Volunteer Wash near Bellemont, Arizona 135 

131 

0.0726 

09505220 96 Rocky Gulch near Stoneman Lake, Arizona 1.85 

1.40 

0.1201 

09177500 97 

Region High Elevation 

Taylor Creek near Gateway, Colorado, 15.3 

12.0 

09183500 98 Mill Creek at Sheley Tunnel near Moab, Utah 26.4 

26.8 
Appendix 1 27 

gaging stations in flood regions 8, 11, high elevation, and 6—Continued. 

Peak discharge (cubic feet per second) Gagingstation 

Identifier Recurrence interval (years) Maximum peak Low- Record 

(fig. 1) discharge discharge length number 2 5 10 25 50 100 500 recorded threshold (years) 

Region 11—Continued 

09400560 85	 124 237 333 481 609 755 1,170 383 30 14 

128 325 538 926 1,310 1,800 3,370 -- -- -­

125 250 373 583 778 1,000 1,660 -- -- -­

09400565 86	 365 707 985 1,390 1,720 2,080 3,010 1,130 200 13 

206 514 839 1,420 1,990 2,680 4,910 -- -- -­

344 666 945 1,400 1,810 2,270 3,590 -- -- -­

09400580 87 86 283 523 1,000 1,520 2,200 4,630 707 10 13 

135 330 529 875 1,210 1,610 2,870 -- -- -­

91 292 525 955 1,390 1,950 3,840 -- -- -­

09400650 88 74 166 258 416 571 762 1,380 401 -- 11 

181 446 718 1,200 1,660 2,220 3,980 -- -- -­

82 205 346 604 857 1,160 2,110 -- -- -­

09401220 89 1,510 4,460 7,840 14,200 20,900 29,500 59,000 10,400 100 10 

1,270 3,050 4,780 7,670 10,400 13,500 22,900 -- -- --

1,480 4,120 6,800 11,400 16,000 21,700 40,400 -- -- --

09401245 90 121 191 241 307 359 412 543 290 60 15 

77 195 322 551 780 1,070 1,990 -- -- -­

117 192 257 362 454 556 824 -- -- -­

09401260 91 3,450 5,730 7,470 9,900 11,900 14,000 19,400 10,100 1,300 26 

2,440 5,870 9,240 14,900 20,200 26,300 44,700 -- -- --

3,390 5,750 7,690 10,600 13,100 15,900 23,000 -- -- --

09404050 92	 20 58 101 182 266 374 745 35 -- 14 

58 137 215 345 468 613 1,060 -- -- -­

22 67 120 218 316 438 835 -- -- -­

09404310 93	 14 36 62 110 161 229 473 177 -- 13 

24 59 97 165 233 318 596 -- -- -­

15 40 70 127 185 260 519 -- -- -­

09502800 94 1,300 4,070 7,390 13,900 21,000 30,300 63,600 14,800 -- 21 

1,170 2,860 4,580 7,540 10,400 13,700 24,100 -- -- --

1,290 3,900 6,810 12,200 17,700 24,900 49,700 -- -- --

09503800 95	 507 1,130 1,670 2,500 3,200 3,980 6,060 2,300 200 14 

638 1,540 2,420 3,920 5,330 7,000 12,000 -- -- -­

519 1,200 1,840 2,890 3,820 4,880 7,800 -- -- -­

09505220 96 38 122 235 490 804 1,270 3,380 1,550 10 

113 283 463 788 1,110 1,510 2,790 -- -- -­

40 132 256 530 853 1,320 3,260 -- -- -­

Region High Elevation 

09177500 97 111 264 407 637 843 1,080 1,770 555 -- 24 

88 196 299 471 631 822 1,410 -- -- -­

108 245 368 566 748 964 1,610 -- -- -­

09183500 98	 197 452 710 1,170 1,620 2,190 4,080 1,080 -- 17 

134 288 433 670 887 1,140 1,910 -- -- -­

186 400 594 919 1,230 1,620 2,880 -- -- -­

30 
28 Magnitude and Frequency of Peak Discharges for the Navajo Nation in Arizona, Utah, Colorado, and New Mexico 

Appendix 1. Selected basin, climatic, and flood characteristics, maximum peak discharge recorded and low-discharge threshold for 

Gagingstation 

number 

09317997 

Identifier 

(fig. 1) 

99 

Gaging-station 

name 

Region High Elevation—Continued 

Huntington Creek near Huntington, Utah 

Drainage 

area 

(square 

miles) 

177 

178 

Average 

basin slope 

(percent) 

Average 

basin 

elevation 

(feet) 

09326500 100 Ferron Creek near Ferron, Utah 136 

138 

09327550 101 Ferron Creek below Paradise Ranch near Clawson, Utah 218 

221 

09329900 102 Pine Creek near Bicknell, Utah 107 

104 

09330230 103 Fremont River near Caineville, Utah 1,200 

1,210 

09330500 104 Muddy Creek near Emery, Utah 108 

105 

09331500 105 Ivie Creek above Diversions near Emery, Utah 45.1 

50.0 

09332100 106 Muddy Creek below Interstate 70 near Emery, Utah 414 

418 

09332500 107 Muddy Creek below Ivie Creek near Emery, Utah 430 

440 

09337000 108 Pine Creek near Escalante, Utah 66.7 

68.1 

09337500 109 Escalante River near Escalante, Utah 315 

320 

09338000 110 East Fork Boulder Creek near Boulder, Utah 20.4 

21.4 

09338500 111 East Fork Deer Creek near Boulder, Utah 1.70 

1.90 

09378170 112 South Creek above reservoir near Monticello, Utah 8.25 

8.64 
Appendix 1 29 

gaging stations in flood regions 8, 11, high elevation, and 6—Continued. 

Peak discharge (cubic feet per second) Gagingstation 

Identifier Recurrence interval (years) Maximum peak Low- Record 

(fig. 1) discharge discharge length number 2 5 10 25 50 100 500 recorded threshold (years) 

Region High Elevation—Continued 

09317997 99	 832 1,580 2,190 3,090 3,840 4,660 6,870 1,680 -- 17 

576 1,110 1,580 2,290 2,900 3,590 5,510 -- -- -­

793 1,450 1,970 2,740 3,410 4,170 6,250 -- -- -­

09326500 100	 818 1,330 1,760 2,410 2,980 3,650 5,590 4,180 300 64 

471 924 1,320 1,930 2,460 3,060 4,750 -- -- -­

800 1,290 1,700 2,330 2,890 3,540 5,440 -- -- -­

09327550 101 1,240 2,130 2,800 3,730 4,480 5,260 7,230 2,670 -- 11 

675 1,290 1,820 2,620 3,300 4,070 6,180 -- -- --

1,110 1,810 2,340 3,130 3,820 4,590 6,660 -- -- --

09329900 102 74 232 422 798 1,210 1,750 3,720 707 -- 16 

392 779 1,120 1,650 2,120 2,650 4,160 -- -- -­

95 323 601 1,090 1,560 2,130 3,920 -- -- -­

09330230 103 1,760 3,400 4,700 6,560 8,080 9,700 13,900 8,800 -- 33 

2,500 4,350 5,810 7,880 9,570 11,400 16,000 -- -- --

1,800 3,480 4,840 6,780 8,340 10,000 14,200 -- -- --

09330500 104	 467 1,000 1,520 2,420 3,280 4,350 7,820 3,340 -- 56 

394 784 1,130 1,660 2,130 2,670 4,180 -- -- -­

463 979 1,460 2,270 3,030 3,960 6,940 -- -- -­

09331500 105	 190 392 577 875 1,150 1,470 2,430 1,240 50 24 

202 422 623 946 1,240 1,580 2,570 -- -- -­

192 399 591 900 1,180 1,510 2,490 -- -- -­

09332100 106 1,220 2,210 3,080 4,500 5,800 7,350 12,100 9,400 300 30 

1,100 2,040 2,820 3,960 4,930 5,990 8,840 -- -- --

1,210 2,180 3,030 4,360 5,560 6,960 11,200 -- -- --

09332500 107 1,100 1,690 2,110 2,680 3,120 3,580 4,720 2,890 200 17 

1,140 2,090 2,890 4,060 5,050 6,130 9,030 -- -- --

1,100 1,770 2,310 3,100 3,740 4,410 6,060 -- -- --

09337000 108	 181 366 532 797 1,040 1,310 2,140 1,010 50 47 

273 557 814 1,220 1,580 2,000 3,200 -- -- -­

185 384 571 871 1,140 1,450 2,350 -- -- -­

09337500 109	 827 1,740 2,540 3,750 4,790 5,960 9,130 4,550 100 44 

896 1,680 2,340 3,320 4,160 5,080 7,590 -- -- -­

830 1,740 2,510 3,670 4,660 5,770 8,800 -- -- -­

09338000 110	 199 303 375 467 537 607 773 483 -- 20 

110 240 364 567 755 978 1,650 -- -- -­

183 285 371 507 625 754 1,090 -- -- -­

09338500 111	 20 64 122 248 398 614 1,520 350 -- 20 

16 41 67 114 161 219 414 -- -- -­

19 57 98 178 264 383 840 -- -- -­

09378170 112	 70 105 130 164 192 220 293 163 30 

55 126 196 316 430 567 998 -- -- -­

66 113 160 240 311 392 616 -- -- -­

14 
30 Magnitude and Frequency of Peak Discharges for the Navajo Nation in Arizona, Utah, Colorado, and New Mexico 

Appendix 1. Selected basin, climatic, and flood characteristics, maximum peak discharge recorded and low-discharge threshold for 

Gagingstation 

number 

09378630 

Identifier 

(fig. 1) 

113 

Gaging-station 

name 

Region High Elevation—Continued 

Recapture Creek near Blanding, Utah 

Drainage 

area 

(square 

miles) 

3.88 

3.77 

Average 

basin slope 

(percent) 

Average 

basin 

elevation 

(feet) 

09378650 114 Recapture Creek below Johnson Creek near Blanding, Utah 37.1 

50.2 

09383600 115 Fish Creek near Eager, Arizona 17.0 

16.9 

09386100 116 Largo Creek near Quemado, New Mexico 138 

151 

09386900 117 Rio Nutria near Ramah, New Mexico 71.2 

71.4 

09408400 118 Santa Clara River near Pine Valley, Utah 18.3 

18.7 

09442650 119 Romero Creek near Arizona State line near Luna, New Mexico 9.37 

10.8 

09489200 120 Pacheta Creek near Maverick, Arizona 16.4 

14.8 

09489700 121 Big Bonito Creek near Fort Apache, Arizona 114 

119 

09490800 122 North Fork White River near Greer, Arizona 39.3 

40.2 

09491000 123 North Fork White River near McNary, Arizona 69.1 

78.2 

08313100 124 

Region 6 

Canada Ancha tributary near Santa Fe, New Mexico 0.577 

1.23 

08316600 125 North Frijoles Arroyo near Santa Fe, New Mexico 0.356 

0.330 

08316650 126 Arroyo de los Frijoles, Locust Tree, near Santa Fe, New Mexico 1.40 

1.30 
Appendix 1 31 

gaging stations in flood regions 8, 11, high elevation, and 6—Continued. 

Peak discharge (cubic feet per second) Gagingstation 

Identifier Recurrence interval (years) Maximum peak Low- Record 

(fig. 1) discharge discharge length number 2 5 10 25 50 100 500 recorded threshold (years) 

Region High Elevation—Continued 

09378630 113	 15 36 58 99 139 191 364 97 1 34 

31 74 118 194 269 360 655 -- -- -­

16 41 69 121 171 234 439 -- -- -­

09378650 114	 120 330 546 914 1,260 1,670 2,890 695 -- 18 

174 367 546 834 1,100 1,400 2,310 -- -- -­

127 340 546 877 1,180 1,530 2,590 -- -- -­

09383600 115	 62 163 258 408 539 684 1,070 236 50 13 

96 211 321 504 674 876 1,490 -- -- -­

68 180 287 458 613 790 1,300 -- -- -­

09386100 116	 313 552 761 1,090 1,390 1,740 2,800 1,320 250 42 

476 934 1,330 1,950 2,490 3,090 4,790 -- -- -­

335 644 944 1,420 1,840 2,310 3,640 -- -- -­

09386900 117	 338 676 954 1,360 1,700 2,070 3,030 1,840 -- 30 

287 583 851 1,270 1,650 2,080 3,310 -- -- -­

333 659 928 1,330 1,680 2,070 3,120 -- -- -­

09408400 118 87 209 342 597 869 1,230 2,570 340 -- 40 

101 222 338 528 706 916 1,550 -- -- -­

90 214 340 557 768 1,030 1,900 -- -- -­

09442650 119	 56 145 244 436 643 918 1,940 480 -- 19 

61 138 214 343 465 612 1,070 -- -- -­

57 143 231 388 545 744 1,430 -- -- -­

09489200 120 105 179 234 312 374 439 607 312 20 23 

93 205 313 492 659 858 1,460 -- -- -­

104 185 258 372 472 583 878 -- -- -­

09489700 121	 644 1,510 2,370 3,840 5,240 6,950 12,300 4,510 -- 24 

411 815 1,170 1,720 2,210 2,750 4,310 -- -- -­

615 1,340 1,960 2,930 3,850 4,950 8,400 -- -- -­

09490800 122	 188 261 315 390 451 516 689 299 100 13 

182 382 568 866 1,140 1,450 2,380 -- -- -­

186 297 408 588 742 911 1,360 -- -- -­

09491000 123	 404 740 1,030 1,480 1,890 2,350 3,720 2,310 -- 39 

280 571 833 1,250 1,620 2,040 3,260 -- -- -­

394 713 987 1,420 1,810 2,260 3,590 -- -- -­

Region 6 

08313100 124 17 71 147 316 517 802 1,940 298 5 

105 255 397 636 860 1,130 1,940 -- -- -­

19 80 170 367 588 882 1,940 -- -- -­

08316600 125 141 242 320 429 518 612 856 360 20 13 

86 211 330 531 721 948 1,640 -- -- -­

135 236 323 462 590 739 1,160 -- -- -­

08316650 126	 510 1,010 1,450 2,100 2,680 3,320 5,120 1,900 40 

153 361 558 884 1,190 1,550 2,650 -- -- -­

464 864 1,160 1,590 1,980 2,440 3,820 -- -- -­

32 

14 
32 Magnitude and Frequency of Peak Discharges for the Navajo Nation in Arizona, Utah, Colorado, and New Mexico 

Appendix 1. Selected basin, climatic, and flood characteristics, maximum peak discharge recorded and low-discharge threshold for 

Gagingstation 

number 

08316700 

Identifier 

(fig. 1) 

127 

Gaging-station 

name 

Region 6—Continued 

Arroyo de los Frijoles near Santa Fe, New Mexico 

Drainage 

area 

(square 

miles) 

2.80 

2.92 

Average 

basin slope 

(percent) 

Average 

basin 

elevation 

(feet) 

08317600 128 San Cristobal Arroyo near Galisteo, New Mexico 114 

116 

08317700 129 Tarhole Canyon near Galisteo, New Mexico 2.06 

2.15 

08317720 130 Canada de la Cueva near Galisteo, New Mexico 1.77 

1.79 

08318000 131 Galisteo Creek at Domingo, New Mexico 661 

640 

08318900 132 San Pedro Creek near Golden, New Mexico 44.7 

45.2 

08330500 133 Tijeras Arroyo at Albuquerque, New Mexico 74.7 

75.3 

08330600 134 Tijeras Arroyo near Albuquerque, New Mexico 134 

128 

08331100 135 Belen Highline Canal tributary near Los Lunas, New Mexico 0.180 

0.160 

08331650 136 Cañada Montoso near Scholle, New Mexico 37.0 

35.0 

08334000 137 Rio Puerco above Arroyo Chico near Guadalupe, New Mexico 420 

420 

08340500 138 Arroyo Chico near Guadalupe, New Mexico 1,360 

1,390 

08343100 139 Grants Canyon at Grants, New Mexico 11.8 

13.0 

08351500 140 Rio San Jose at Correo, New Mexico 3,650 

3,660 
Appendix 1 33 

gaging stations in flood regions 8, 11, high elevation, and 6—Continued. 

Peak discharge (cubic feet per second) Gagingstation 

Identifier Recurrence interval (years) Maximum peak Low- Record 

(fig. 1) discharge discharge length number 2 5 10 25 50 100 500 recorded threshold (years) 

Region 6—Continued 

08316700 127	 473 1,540 2,910 5,840 9,240 14,000 33,300 5,340 30 14 

205 475 728 1,140 1,530 1,990 3,370 -- -- -­

444 1,290 2,130 3,500 4,790 6,420 12,200 -- -- -­

08317600 128 1,820 3,500 5,010 7,440 9,680 12,300 20,300 13,200 800 40 

971 2,050 3,010 4,540 5,920 7,520 12,200 -- -- --

1,800 3,420 4,830 7,040 9,050 11,400 18,600 -- -- --

08317700 129	 315 731 1,120 1,740 2,310 2,960 4,840 2,440 250 34 

180 420 647 1,020 1,370 1,780 3,030 -- -- -­

309 703 1,050 1,600 2,080 2,640 4,300 -- -- -­

08317720 130	 114 255 397 647 896 1,210 2,250 919 -- 25 

169 396 611 964 1,290 1,690 2,870 -- -- -­

117 268 426 711 993 1,340 2,450 -- -- -­

08318000 131 6,440 11,000 14,700 20,100 24,700 29,800 43,900 22,800 2,000 29 

2,030 4,090 5,900 8,720 11,200 14,100 22,500 -- -- --

6,240 10,400 13,500 18,000 21,700 25,900 38,000 -- -- --

08318900 132	 928 1,550 2,120 3,060 3,950 5,040 8,610 10,800 600 44 

655 1,410 2,100 3,200 4,210 5,380 8,630 -- -- -­

922 1,550 2,120 3,070 3,980 5,090 8,640 -- -- -­

08330500 133	 702 1,870 3,070 5,150 7,140 9,530 16,900 6,500 450 47 

813 1,730 2,560 3,880 5,070 6,460 10,600 -- -- -­

704 1,870 3,040 5,000 6,840 9,020 15,600 -- -- -­

08330600 134 664 1,160 1,570 2,160 2,670 3,230 4,770 2,930 -- 45 

1,040 2,180 3,200 4,820 6,280 7,970 12,900 -- -- -­

670 1,190 1,640 2,330 2,950 3,640 5,550 -- -- -­

08331100 135 199 310 390 497 580 666 878 480 -- 41 

65 161 254 412 562 742 1,300 -- -- -­

192 297 373 483 576 680 960 -- -- -­

08331650 136	 369 1,090 1,970 3,780 5,820 8,660 19,800 5,600 -- 37 

605 1,310 1,960 2,990 3,930 5,020 8,260 -- -- -­

374 1,100 1,970 3,670 5,500 7,920 16,800 -- -- -­

08334000 137 1,890 3,070 3,900 4,970 5,780 6,590 8,490 6,940 1,000 48 

1,680 3,420 4,960 7,370 9,530 12,000 19,200 -- -- --

1,890 3,090 3,950 5,140 6,080 7,070 9,480 -- -- --

08340500 138 4,030 6,800 9,040 12,400 15,200 18,300 27,200 15,200 1,000 43 

2,750 5,430 7,770 11,400 14,600 18,300 29,000 -- -- --

4,010 6,740 8,960 12,300 15,100 18,300 27,400 -- -- --

08343100 139	 175 508 844 1,400 1,900 2,470 4,050 1,550 -- 34 

375 837 1,260 1,950 2,590 3,330 5,550 -- -- -­

179 525 879 1,470 2,010 2,630 4,360 -- -- -­

08351500 140 1,420 3,070 4,560 6,880 8,950 11,300 18,000 11,000 -- 52 

4,160 8,020 11,300 16,500 21,000 26,100 40,800 -- -- --

1,440 3,160 4,750 7,320 9,630 12,300 19,700 -- -- --
34 Magnitude and Frequency of Peak Discharges for the Navajo Nation in Arizona, Utah, Colorado, and New Mexico 

Appendix 1. Selected basin, climatic, and flood characteristics, maximum peak discharge recorded and low-discharge threshold for 

Gagingstation 

number 

08352500 

Identifier 

(fig. 1) 

141 

Gaging-station 

name 

Region 6—Continued 

Rio Puerco at Rio Puerco, New Mexico 

Drainage 

area 

(square 

miles) 

6,130 

6,590 

Average 

basin slope 

(percent) 

Average 

basin 

elevation 

(feet) 

08353000 142 Rio Puerco near Bernardo, New Mexico 7,220 

7,350 

08354000 143 Rio Salado near San Acacia, New Mexico 1,380 

1,380 

08358600 144 Chupadera Wash tributary at Bingham, New Mexico 0.765 

1.29 

08480150 145 White Oaks Canyon near Carrizozo, New Mexico 35.1 

31.0 

08489000 146 Big Draw near Mountainair, New Mexico 4.08 

3.90 
Appendix 1 35 

gaging stations in flood regions 8, 11, high elevation, and 6—Continued. 

Gagingstation 

number 

Identifier 

(fig. 1) 

2 5 

Peak discharge (cubic feet per second) 

Recurrence interval (years) Maximum peak 

discharge 

recorded 10 25 50 100 500 

Lowdischarge 

threshold 

Record 

length 

(years) 

Region 6—Continued 

08352500 141 5,180 10,300 14,900 22,500 29,600 38,000 63,800 37,700 -- 51 

5,170 9,830 13,800 20,000 25,400 31,500 48,900 -- -- --

5,180 10,300 14,900 22,400 29,200 37,300 62,000 -- -- --

08353000 142 2,690 5,480 7,980 12,000 15,500 19,700 31,900 18,800 -- 60 

5,540 10,500 14,700 21,200 26,900 33,400 51,700 -- -- --

2,710 5,560 8,150 12,300 16,100 20,500 33,300 -- -- --

08354000 143 7,250 15,100 21,300 30,000 36,800 44,000 61,200 36,200 1,000 38 

2,770 5,470 7,820 11,500 14,700 18,400 29,100 -- -- --

7,120 14,500 20,000 27,300 33,000 39,100 54,500 -- -- --

08358600 144 79 223 362 582 774 987 1,550 620 -- 35 

119 285 443 706 953 1,250 2,140 -- -- -­

80 227 370 601 807 1,040 1,680 -- -- -­

08480150 145 1,110 1,980 2,770 4,050 5,250 6,690 11,300 7,690 -- 39 

592 1,290 1,920 2,930 3,850 4,930 8,110 -- -- --

1,090 1,940 2,690 3,900 5,030 6,380 10,600 -- -- --

08489000 146 45 182 370 773 1,230 1,850 4,170 1,710 30 40 

240 550 841 1,320 1,760 2,280 3,840 -- -- -­

47 195 401 835 1,310 1,930 4,100 -- -- -­
Blank Page 
Magnitude and Frequency of Peak

Discharges for the Navajo Nation in 

Arizona, Utah, Colorado, and New 

Mexico

Appendix 2

Appendix 2—Basin and Climatic 

Characteristics Determined Using 

Geographical Information System Weasel 
Blank Page 
Appendix 2. Basin and climatic characteristics determined using Geographical Information System Weasel (U.S. Geological Survey, 

2000)—Continued.

Appendix 2 39 

Appendix 2. Basin and climatic characteristics determined using Geographical Information System Weasel (U.S. Geological Survey, 

2000). 

[NOAA2, NOAA14, National Oceanic and Atmospheric Administration Atlases 2 and 14, respectively; NAVD88, North American Vertical Datum of 1988] 

Average Average Average Average 

Station 

number 

Average 

basin 

mean 

annual 

precipitation 

(inches), 

1961–90 

Average 

basin 

mean 

winter 

precipitation 

(inches), 

1961–90 

basin 

maximum 

24-hour 

precipitation 

for 100-year 

recurrence 

interval— 

NOAA2 

basin 

maximum 

6-hour 

precipitation 

for 100-year 

recurrence 

interval— 

NOAA2 

basin 

maximum 

24-hour 

precipitation 

for 100-year 

recurrence 

interval— 

NOAA14 

basin 

maximum 

6-hour 

precipitation 

for 100-year 

recurrence 

interval— 

NOAA14 

Average 

basin 

slope 

(percent) 

Drainage 

area 

(square 

miles) 

Average 

basin 

elevation 

(feet 

above 

NAVD88) 

Average 

basin 

aspect 

(azimuth 

degree) 

(inches) (inches) (inches) (inches) 

08313100 14.60 5.70 2.94 2.31 3.28 2.62 0.0354 0.577 6,520 45 

08316600 12.90 5.07 3.00 2.53 3.13 2.59 0.0757 0.356 7,260 180 

08316650 12.80 5.01 3.00 2.51 3.12 2.58 0.0696 1.40 7,170 315 

08316700 13.00 5.01 2.99 2.46 3.13 2.57 0.0709 2.80 7,080 315 

08317600 15.64 5.81 3.65 2.86 3.54 2.86 0.0903 114 7,130 225 

08317700 13.27 4.94 3.62 2.83 3.42 2.82 0.0985 2.06 6,660 270 

08317720 12.89 4.92 3.34 2.68 3.25 2.68 0.0561 1.77 6,260 180 

08318000 13.54 5.14 3.41 2.71 3.30 2.70 0.1001 661 6,470 270 

08318900 16.80 7.56 3.59 2.76 3.47 2.56 0.1464 44.7 6,900 90 

08330500 16.70 7.47 3.54 2.76 3.54 2.53 0.2024 74.7 6,980 90 

08330600 14.72 6.48 3.38 2.68 3.31 2.45 0.1833 134 6,690 270 

08331100 9.44 3.71 2.64 2.30 2.75 2.26 0.0501 0.180 5,360 315 

08331650 14.40 5.66 3.44 2.73 3.77 2.73 0.0886 37.0 6,310 315 

08334000 14.10 6.61 3.13 2.44 3.10 2.40 0.1357 420 7,100 270 

08340500 10.50 4.35 2.81 2.22 2.69 2.18 0.0790 1,360 6,800 0 

08343100 11.02 4.37 2.83 2.26 2.70 2.23 0.1703 11.8 7,020 180 

08351500 12.33 5.19 2.87 2.23 2.90 2.40 0.0868 3,650 7,240 0 

08352500 11.60 4.87 2.88 2.27 2.82 2.32 0.0923 6,130 6,900 0 

08353000 11.53 4.80 2.88 2.27 2.83 2.34 0.0879 7,220 6,850 0 

08354000 11.85 4.17 3.03 2.45 3.10 2.54 0.1261 1,380 6,710 90 

08358600 11.52 3.98 3.34 2.73 3.55 2.94 0.0870 0.765 5,610 315 

08480150 15.87 5.82 4.30 3.29 3.99 3.33 0.2096 35.1 6,740 270 

08489000 16.06 6.74 4.03 2.92 4.06 3.01 0.0345 4.08 7,000 135 

09163700 9.32 5.53 2.42 1.78 2.34 2.06 0.1241 90.7 4,820 180 

09181000 12.97 7.56 2.79 1.89 2.80 2.38 0.3612 20.2 5,640 45 

09182600 9.36 5.21 2.45 1.77 2.38 2.13 0.0541 1.43 5,050 135 

09183000 9.52 5.58 2.42 1.76 2.70 2.39 0.1224 161 4,770 270 

09184000 20.11 12.19 2.94 1.97 3.47 2.83 0.2709 73.3 7,060 270 

09185200 15.77 9.15 2.88 1.92 3.08 2.64 0.2167 17.2 6,270 315 

09185500 13.67 7.79 2.95 2.00 3.15 2.26 0.0869 366 6,730 270 

09187000 18.70 11.48 3.22 2.19 3.68 2.47 0.3029 113 7,380 90 

09314250 17.05 10.68 2.99 2.08 2.75 2.09 0.2490 946 7,660 90 

09314280 9.60 4.88 2.59 1.78 2.33 1.74 0.0613 206 5,750 90 

09314500 14.07 8.27 2.84 1.97 2.61 1.97 0.2025 1,730 6,500 90 

09315200 8.07 4.36 2.58 1.76 2.48 1.88 0.1740 4.92 4,830 270 

09315900 6.80 3.58 2.40 1.76 2.37 1.78 0.0547 3.04 4,320 45 
40 Magnitude and Frequency of Peak Discharges for the Navajo Nation in Arizona, Utah, Colorado, and New Mexico 

Appendix 2. Basin and climatic characteristics determined using Geographical Information System Weasel (U.S. Geological Survey, 

2000)—Continued. 

Average Average Average Average 

basin basin basin basin Average Average maximum maximum maximum maximum Average basin basin 24-hour 6-hour 24-hour 6-hour Average Drainage basin 

Average 

mean mean basin Station 

annual winter precipitation precipitation precipitation precipitation basin area elevation 

aspect 

number 

precipitation precipitation 

for 100-year for 100-year for 100-year for 100-year slope (square (feet (azimuth 

(inches), (inches), recurrence recurrence recurrence recurrence (percent) miles) above degree) interval— interval— interval— interval— NAVD88) 1961–90 1961–90 NOAA2 NOAA2 NOAA14 NOAA14 

(inches) (inches) (inches) (inches) 

09316000 9.08 5.05 2.54 1.8 2.61 1.99 0.2154 78.1 5,030 225 

09327600 8.48 4.24 2.42 1.75 2.24 1.68 0.0793 0.620 6,180 315 

09328300 8.98 4.40 2.64 1.83 2.40 1.87 0.1393 18.4 6,400 0 

09328600 9.55 4.61 2.71 1.87 2.50 1.95 0.1126 6.95 6,940 90 

09328700 7.63 3.79 2.53 1.8 2.36 1.86 0.0898 44.2 5,200 135 

09330120 10.63 5.45 3.06 2.06 2.83 1.94 0.2344 54.0 6,980 180 

09330200 12.84 7.38 3.40 2.29 3.05 2.12 0.2334 78.5 7,400 90 

09330300 6.26 3.13 2.39 1.76 2.26 1.75 0.0730 22.5 4,790 225 

09330400 13.42 7.90 3.18 2.12 2.83 2.07 0.1740 1,900 7,280 90 

09334000 7.38 4.14 2.88 1.95 2.49 1.88 0.2501 135 5,120 135 

09336400 14.84 8.81 3.78 2.64 3.38 2.36 0.2187 53.9 7,520 90 

09338900 13.67 8.10 3.86 2.56 3.43 2.23 0.2127 65.4 7,360 180 

09339200 11.32 6.33 3.36 2.39 3.22 2.16 0.2699 144 6,460 90 

09357200 10.35 5.05 2.70 2.16 2.79 2.06 0.0231 0.060 6,650 315 

09357230 10.20 5.65 2.69 2.11 2.65 2.03 0.0491 0.29 5,980 90 

09367530 8.78 5.24 2.70 2.13 2.47 1.96 0.0720 2.68 5,500 135 

09367550 8.83 5.28 2.68 2.11 2.48 1.94 0.0569 4.72 5,490 180 

09367561 10.80 6.44 2.76 2.18 2.69 2.00 0.1109 134 5,640 180 

09367860 12.84 6.14 3.17 2.42 3.15 2.36 0.1922 9.78 7,240 225 

09367900 12.25 6.07 3.05 2.30 3.00 2.32 0.1513 7.13 6,690 90 

09367930 9.22 4.54 2.64 2.11 2.69 2.06 0.0494 45.0 6,200 180 

09367950 9.79 4.76 2.61 2.09 2.67 2.17 0.0681 4,350 6,290 0 

09367980 8.14 4.57 2.37 2.00 2.47 1.94 0.0317 21.3 5,230 90 

09368020 10.40 6.14 2.72 2.19 2.56 1.94 0.0567 2.02 5,330 225 

09371000 18.50 11.22 3.14 2.23 2.88 2.08 0.2422 523 6,940 270 

09378480 18.27 11.28 3.30 2.28 4.08 2.44 0.1209 142 7,030 90 

09378950 13.26 7.82 3.17 2.18 3.10 2.20 0.2549 10.3 5,810 90 

09379000 12.39 7.43 3.11 2.18 2.97 2.17 0.2009 276 5,880 90 

09379030 10.06 5.48 2.90 2.19 2.79 2.21 0.1031 73.5 5,830 90 

09379060 9.61 5.36 2.95 2.26 2.73 2.08 0.0319 1.36 5,830 315 

09379300 9.45 5.59 3.13 2.17 2.64 2.04 0.1831 65.2 5,190 225 

09379560 7.85 4.34 2.71 2.09 2.51 2.01 0.1348 6.07 5,620 45 

09379800 7.23 4.88 3.05 2.28 2.71 1.98 0.1508 89.6 4,840 0 

09379820 8.76 4.81 2.89 2.19 2.75 2.00 0.0785 4.81 5,100 0 

09381800 11.77 6.75 3.39 2.55 3.01 2.16 0.2335 642 6,260 90 

09382000 11.56 6.54 3.22 2.44 3.11 2.21 0.1874 1,060 6,170 0 

09385800 12.26 5.32 3.17 2.39 3.07 2.54 0.0985 0.350 6,360 0 

09403780 14.48 9.24 3.42 2.68 3.36 2.35 0.1294 1,080 5,870 315 

09403800 11.90 7.37 3.68 2.84 3.01 2.24 0.2243 2.48 5,050 225 
Appendix 2 41 

Appendix 2. Basin and climatic characteristics determined using Geographical Information System Weasel (U.S. Geological Survey, 

2000)—Continued. 

Average Average Average Average 

basin basin basin basin Average Average maximum maximum maximum maximum Average basin basin 24-hour 6-hour 24-hour 6-hour Average Drainage basin 

Average 

mean mean basin Station 

annual winter precipitation precipitation precipitation precipitation basin area elevation 

aspect 

number 

precipitation precipitation 

for 100-year for 100-year for 100-year for 100-year slope (square (feet (azimuth 

(inches), (inches), recurrence recurrence recurrence recurrence (percent) miles) above degree) interval— interval— interval— interval— NAVD88) 1961–90 1961–90 NOAA2 NOAA2 NOAA14 NOAA14 

(inches) (inches) (inches) (inches) 

09404500 14.49 9.29 3.75 2.80 3.49 2.25 0.1297 8.26 5,960 90 

09404900 15.65 10.13 3.65 2.85 3.52 2.28 0.2449 339 6,180 90 

09405420 22.94 15.41 4.26 3.16 4.05 2.59 0.3130 29.4 7,750 180 

09406300 18.63 12.32 4.06 2.80 4.14 3.00 0.3537 9.74 7,720 270 

09406700 22.05 15.13 3.85 2.97 4.20 2.90 0.4447 11.0 6,840 90 

09406800 20.34 13.89 3.76 2.93 4.05 2.81 0.4152 13.7 6,590 90 

09407200 16.80 11.31 3.68 2.81 3.72 2.65 0.2998 200 5,920 135 

09408000 16.97 11.66 3.54 2.87 3.99 2.77 0.3708 15.3 6,130 180 

09408150 14.73 9.87 3.57 2.77 3.47 2.46 0.2830 700 5,250 135 

09409100 22.65 15.80 4.04 2.93 4.12 3.02 0.2783 111 7,230 270 

09409500 22.64 16.87 3.58 2.85 4.34 2.91 0.2953 33.5 6,010 180 

09386200 14.31 6.27 2.94 2.25 3.11 2.63 0.0827 1,820 7,300 0 

09386950 15.11 7.67 2.83 2.20 3.19 2.57 0.0871 831 7,280 0 

09387050 14.37 7.01 2.82 2.23 3.16 2.59 0.0729 18.5 7,440 315 

09390500 27.71 16.04 5.12 3.69 4.88 3.71 0.0579 67.9 7,240 270 

09395100 9.38 4.38 2.87 2.20 3.12 2.49 0.0298 1.16 5,450 315 

09395200 19.81 10.47 5.50 3.81 4.42 3.26 0.0640 15.8 6,670 90 

09395500 13.29 6.48 2.87 2.23 3.08 2.52 0.1106 548 7,230 0 

09395600 12.26 6.08 2.7 2.15 3.00 2.38 0.0451 0.280 6,760 225 

09395900 13.6 6.67 3.12 2.35 3.26 2.39 0.1188 491 7,370 135 

09396100 13.06 6.48 2.95 2.27 3.18 2.47 0.0976 2,150 6,990 135 

09396400 9.56 4.66 2.85 2.09 3.01 2.39 0.0653 0.750 5,720 135 

09397100 10.70 5.50 2.97 2.28 3.10 2.38 0.0471 806 5,980 180 

09397500 23.91 14.42 5.36 3.83 5.05 3.62 0.1132 27.0 7,110 90 

09397800 23.15 13.39 5.53 3.85 4.82 3.53 0.0802 27.5 6,950 90 

09398000 18.54 10.16 4.57 3.34 4.18 3.12 0.0686 983 6,430 0 

09398500 26.91 16.86 5.21 3.65 5.73 3.83 0.1533 316 7,160 90 

09400100 12.02 6.37 3.28 2.49 3.11 2.40 0.0379 8.89 6,730 315 

09400200 11.62 6.34 3.09 2.48 3.13 2.39 0.0863 0.156 6,810 225 

09400290 10.46 5.80 3.04 2.47 3.09 2.32 0.0675 19.8 6,340 90 

09400300 10.15 5.56 3.05 2.47 3.07 2.28 0.0690 68.0 6,140 135 

09400530 9.28 4.39 3.04 2.24 2.74 2.22 0.0177 6.25 5,420 45 

09400560 9.35 5.16 3.00 2.26 2.87 2.20 0.1545 1.76 5,940 90 

09400565 10.79 6.05 3.08 2.48 3.09 2.31 0.1236 6.33 6,940 135 

09400580 9.67 5.04 2.91 2.19 2.97 2.28 0.0726 5.16 5,780 270 

09400650 24.06 15.32 4.74 3.39 4.74 3.08 0.0884 7.44 7,160 90 

09401220 13.70 7.48 3.28 2.50 3.39 2.57 0.0744 558 6,460 90 

09401245 11.78 6.90 2.87 2.27 3.09 2.30 0.1247 0.800 6,650 270 

09401260 10.00 5.91 2.88 2.25 2.94 2.20 0.0955 1,590 6,160 270 
42 Magnitude and Frequency of Peak Discharges for the Navajo Nation in Arizona, Utah, Colorado, and New Mexico 

Appendix 2. Basin and climatic characteristics determined using Geographical Information System Weasel (U.S. Geological Survey, 

2000)—Continued. 

Average Average Average Average 

Station 

number 

Average 

basin 

mean 

annual 

precipitation 

(inches), 

1961–90 

Average 

basin 

mean 

winter 

precipitation 

(inches), 

1961–90 

basin 

maximum 

24-hour 

precipitation 

for 100-year 

recurrence 

interval— 

NOAA2 

basin 

maximum 

6-hour 

precipitation 

for 100-year 

recurrence 

interval— 

NOAA2 

basin 

maximum 

24-hour 

precipitation 

for 100-year 

recurrence 

interval— 

NOAA14 

basin 

maximum 

6-hour 

precipitation 

for 100-year 

recurrence 

interval— 

NOAA14 

Average 

basin 

slope 

(percent) 

Drainage 

area 

(square 

miles) 

Average 

basin 

elevation 

(feet 

above 

NAVD88) 

Average 

basin 

aspect 

(azimuth 

degree) 

(inches) (inches) (inches) (inches) 

09404050 18.35 10.85 3.50 2.75 4.13 2.97 0.0320 2.51 6,120 0 

09404310 11.49 6.16 3.17 2.78 3.64 3.21 0.0833 0.110 5,320 180 

09502800 15.10 7.96 4.64 3.52 4.22 2.98 0.1196 253 5,010 0 

09503800 24.92 15.92 4.93 3.53 4.81 3.13 0.0726 135 7,390 225 

09505220 29.49 20.38 6.47 4.37 5.49 3.83 0.1201 1.85 7,220 180 

09177500 24.27 15.00 3.12 2.03 4.00 2.79 0.1549 15.3 8,840 45 

09183500 27.26 17.23 3.21 2.10 3.97 3.03 0.3404 26.4 8,770 225 

09317997 25.78 17.40 3.62 2.34 3.04 2.44 0.3808 177 9,170 90 

09326500 24.07 15.87 3.62 2.33 3.34 2.26 0.2512 136 8,940 90 

09327550 18.88 11.94 3.24 2.14 2.98 2.08 0.2086 218 8,030 90 

09329900 19.13 12.44 3.82 2.47 3.35 2.43 0.1179 107 9,270 0 

09330230 16.53 10.07 3.38 2.22 2.98 2.18 0.1751 1,200 8,360 90 

09330500 24.44 15.69 3.63 2.31 3.27 2.32 0.2562 108 8,750 180 

09331500 21.14 13.30 3.70 2.33 2.90 2.33 0.2202 45.1 8,720 90 

09332100 16.25 9.67 3.09 2.04 2.85 2.03 0.2207 414 7,900 90 

09332500 15.91 9.43 3.06 2.04 2.83 2.02 0.2183 430 7,780 90 

09337000 22.17 14.88 4.18 2.78 3.83 2.67 0.1976 66.7 9,730 270 

09337500 17.44 11.07 3.93 2.67 3.57 2.46 0.2295 315 7,800 90 

09338000 24.33 17.11 4.35 2.97 3.93 2.79 0.1027 20.4 10,960 225 

09338500 19.37 12.74 4.11 2.65 3.75 2.58 0.1323 1.70 9,500 180 

09378170 32.31 21.74 3.44 2.40 4.73 2.71 0.2634 8.25 8,420 90 

09378630 25.39 16.62 3.40 2.40 4.74 2.72 0.3345 3.88 8,380 180 

09378650 23.87 15.51 3.40 2.38 4.38 2.61 0.2386 37.1 7,680 90 

09383600 28.93 15.59 5.26 3.72 4.59 3.80 0.0851 17.0 9,160 90 

09386100 16.97 7.66 3.09 2.28 3.43 2.75 0.1511 138 8,010 315 

09386900 17.74 9.88 2.93 2.25 3.71 2.79 0.0861 71.2 7,960 225 

09408400 28.72 20.06 4.14 3.01 4.48 3.16 0.413 18.3 8,970 315 

09442650 25.83 13.31 3.87 2.92 4.24 3.34 0.1765 9.37 8,760 225 

09489200 28.27 15.83 5.42 3.80 4.59 3.73 0.1396 16.4 8,450 135 

09489700 28.08 16.01 5.65 3.94 4.71 3.70 0.2584 114 8,070 135 

09490800 31.19 17.50 6.12 4.33 4.87 3.88 0.1752 39.3 9,310 0 

09491000 31.25 17.67 6.10 4.27 5.14 3.90 0.1910 69.1 9,180 270 

Prepared by the USGS New Mexico Water Science Center: 

5338 Montgomery, NE, Suite 400 

Albuquerque, New Mexico 87109 

Information regarding water resources in New Mexico is available at 

http: //nm.water.usgs.gov/