Water resources of southern Coconino County, Arizona

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CONTENTS
Page
Abstract.. ..... . . . . ..... .... . .. .. . .. . . ..... . ... . .. . . . . .. . .... . . . . .. 1
Introduction. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2
Purpose and scope............................................ 2
Methods of investigation .................................. ;.... 2
Previous investigations........................................ 5
Acknowledgments ........................ , . . . . . . . . . . . . . . . . . . . . . 5
Geographic setting ................................................. 5
Surface water .............................. " . . . . . . . . . . . . . . . . . . . . . . . 9
Mean annual flow.............................................. 9
Flood peaks.............................................. 14
Flood volumes............................................ 19
Flow-duration curves..................................... 19
Perennial streams and low flows;.............................. 19
Quality of surface water....................................... 22
Ground water ...................................................... 23
Coconino aquifer.............................................. 24'
Occurrence and movement of water ....................... 26
Mogollon Rim-Flagstaff area.. .... ...... ... . .... . . . . . . . 26
Grand Canyon-Williams area .......................... 27
Availability of water...................................... 27
Chemical quality of water................................. 28
Limestone aquifer ............................................. 30
Occurrence and movement of water.... . ... ...... . ..... . .. 30
Availability of water...................................... 31
Chemical quality of water.................... . . . . . . . . . . . . . 32
Other aquifers ................................................ 33
Moenkopi and Chinle Formations .......................... 33
Volcanic rocks ........................................... ' 34
Sedimentary deposits. ...... ... ...... . ... ... ... ...... ..... 34
Development of water resources .................................... 37
Summary ................................................ , . . . . . . . . . . . 39
Selected references................................................. 40
Hydrologic data .................................................... 45
III
IV CONTENTS
ILLUSTRATIONS
[Plates are in pocket]
Plates 1-2. Maps showing:
Figure
1. Generalized geology of southern Coconino
County, Arizona, and potentiometric
contours in the Coconino aquifer.
2. Chemical quality of ground water in the
upper part of the Coconino aquifer in
southern Coconino County.
1. Map showing area of report and Arizona's water
provinces ......................................... .
2. Sketch showing well-numbering system in
Page
3
Arizona............................................ 4
3-5. Maps showing:
3. Mean annual precipitation, 1931-60, and
mean annual temperature, 1941-70 ............ 7
4. Perennial stream reaches, location of
streamflow-gaging stations, and
runoff regions in southern
Coconino County .. ,.......................... 11
5. Hydrologic areas and flood-frequency regions
in southern Coconino County................. 15
6-9. Graphs showing:
6. Drainage area versus mean annual flood 17
7. Ratio of T-year flood to mean annual
flood (Q2.33) ................................ 18
8. Flow-duration curves for selected
streamflow-gaging sites ...................... 21
9. Water levels in selected wells................... 36
CONTENTS v
TABLES
Page
Table 1. Mean flow characteristics at continuous-record
gaging stations....................................... 10
2. Regression equations used to estimate 1- f 3- f and
7-day mean flow volumes on ungaged streams
in runoff regions 1 and 2 for a 50-year
recurrence interval................................... 20
3. Range and median value of dissolved constituents
in water from selected aquifers....................... 28
4. Chemical analyses of water from selected
streamflow sites . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 47
5. Chemical analyses of water from selected springs ....... 51
6. Chemical analyses of water from selected wells.......... 53
VI CONVERSION FACTORS
For readers who prefer to use the metric (51) units, the
conversion factors for the terms used in this report are listed below:
Multiply !!Y To obtain
inch (in. ) 25.4 millimeter (mm)
foot (ft) 0.3048 meter (m)
mile (mi) 1.609 kilometer (km)
acre 0.4047 hectare (ha)
square mile (mi 2 ) 2.590 square kilometer (km2)
acre-foot (acre-ft) 0.001233 cubic hectometer (hm3 )
cubic foot per second 0.02832 cubic meter per second
(ft3/s) (m3/s)
gallon per minute 0.06309 I iter per second
(gal/min) (Lis)
ton (short) 0.0972 tonne (t)
degree Fahrenheit (OF) °C = 5/9 (OF-32) degree Celsius (OC)
WATER RESOURCES OF SOUTHERN COCONINO COUNTY, ARIZONA
By
E. H. McGavock, T. W. Anderson, Otto Moosburner,
and Larry J. Mann
ABSTRACT
Southern Coconino County includes about 10,600 square miles in
north-central Arizona. Water-resources development has been slight, and
less than 8,000 acre-feet of ground water and surface water was used in
1975. The amount of ground water in storage is estimated to be between
100 and 200 million acre-feet. The main sources of ground water are the
Coconino and limestone aquifers.
The Coconino aquifer includes three principal formations,
which in ascending order are the Supai Formation, Coconino Sandstone,
and Kaibab Limestone of Pennsylvanian and Permian age. I n the south­eastern
part of the area, the Naco Formation of Pennsylvanian age under­lies
andintertongues with the lower member of the Supai Formation. The
Coconino aquifer furnishes about 75 percent of the ground water used in
southern Coconino County, although the aquifer does not underlie the
entire area. Depth to water ranges from about 75 feet below land surface
near Winslow to about 2,500 feet below land surface north of Flagstaff,
and well yields range from about 1 to 1,000 gallons per minute. The
chemical quality of the water generally is acceptable for most uses, and
dissolved-solids concentrations generally are less than 500 milligrams per
liter.
The limestone aquifer consists of a sequence of limestone,
dolomite, sandstone, and shale units, which are hydraulically connected.
The units, in ascending order, include the Tapeats Sandstone, Bright
Angel Shale, and Muav Limestone of Cambrian age; the Temple Butte
Limestone, an unnamed limestone unit, and the Martin Formation of
Devonian age; the Redwall Limestone of Mississippian age; and an
unnamed limestone unit of Pennsylvanian age. The limestone aquifer
underlies the entire area and has the greatest water-yielding potential.
Because the depth to water is more than 2,500 feet in most places,
however, the limestone aquifer generally is not tapped by wells.
In places the Moenkopi and Chinle Formations of Triassic age,
volcanic rocks, and sedimentary deposits will yield sufficient water of
suitable chemical quality for livestock and domestic uses. Water occurs at
depths of less than 300 feet below the land surface, and well yields of 10
to 50 gallons per minute are common.
1
2
Streamflow is extremely variable, and most streams are inter­mittent.
Chemical quality of flow in intermittent and perennial streams
during medium to high flows generally is acceptable for most uses;
dissolved-solids concentrations generally are less than 200 milligrams per
liter. Dissolved-solids concentrations in low flows in the perennial
streams range from 200 to 2,000 milligrams per liter.
I n southern Coconino County about 2,600 acre-feet of ground
water and 4,200 acre-feet of surface water was used for public supply
and irrigation in 1970. In 1975 about 5,200 acre-feet of ground water
was withdrawn and about 2,500 acre-feet of surface water was used. The
amount of surface water used annually is dependent on the amount of
precipitation and is extremely variable. Ground-water withdrawals have
not exceeded the rate of recharge, and water levels have been nearly
constant.
INTRODUCTION
Southern Coconino County includes about 10,600 mi2 in north­central
Arizona and is the part of the county south of the Colorado and
Little Colorado Rivers (fig. 1). The area includes the Coconino, Kaibab,
and Sitgreaves National Forests and part of the Grand Canyon National
Park. The steady increase in population, especially near Flagstaff, and
the large seasonal influx of people to the recreational areas have caused
an increasing demand for water supplies of sufficient quantity and suit­able
chemical quality. The study was made by the U. S. Geological
Survey in cooperation with the Arizona State Land Department and the
Arizona Department of Water Resources.
Purpose and Scope
The purpose of the study was to determine the availability,
chemical quality, and use of water in southern Coconino County. The
report describes the (1) surface-water characteristics, (2) distribution
and general water-yielding characteristics of the aquifers, (3) chemical
quality of the water, and (4) amount and effects of water-resources
development in 1975. Data for contiguous parts of Yavapai, Navajo, and
Gila Counties that relate directly to the hydrology of southern Coconino
County are included in the report.
Methods of Investigation
An inventory was made of most wells and springs in the area
(McGavock, 1968), and water samples were collected from selected wells,
springs, and streams for chemical analysis. Chemical-analysis data are
given in tables 4, 5, and 6 at the end of the report. Well and spring
112°
113- ....
ll2'
Ill'
.---. :U4 I
~--i- __ -.J
lll' liD" 109' o 50 100 IIIILU
t-I- 'T,- --I.'_ ,..----.-',I
o 50 100 150 KILOCI$(Tll:e&fI
INDEX MAP SHOWING AREA
OF REPORT (SHADED)
Figure l.--Area of report and Arizona's water provinces.
3
locations are described in accordance with the well-numbering system used
in Arizona, which is explained arid illustrated in figure 2. Lithologic and
drillers' logs of wells and drill cuttings were examined to determine the
water-yielding potential of the aquifers. A reconnaissance geologic map
was compiled from previously published _ maps to emphasize the aquifers as
delineated and discussed in this report.
Records for 39 continuous-record gaging stations and 12
partial-record stations were used to evaluate the surface-water resources
of the area. Gaging stations on streams -are the most common tool for
measuring _ streamflow; however, gaging every stream is impractical.
Certain streamflow characteristics at ungaged sites were estimated by
indirect techniques using data transferred from gaged sites.
Continuous--record gaging stations provided data for the determination of
mean annual flow , flood magnitude and frequency, and low-flow character­istics.
Data, obtained at crest-stage partial-record gaging stations were
used to determine flood magnitude and frequency.
4
R.1W. R.I E. 2 3 • .. R6 E .
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Well A·4·5
R.S E.
6 5 .. 3 2 1
7 8 9 10 11 12
1. 18 17 16 15 14 13
4 f--t~'-t-+-+--l
N. ~9 20 21 22 23 24
30 29 28 27 26 25
31 32 33 34 35 36
The well numbers used by the Geological Survey in Arizona are
in accordance with the Bureau of Land Management's system of land
subdivision. The land survey in Arizona is based on the Gila and Salt
River meridian and base line, which. divide the State into four quadrants.
These quadrants are designated counterclockwise by the capital letters A,
B, C, and D. All land north .and east of the point of origin is in A
quadrant, that north and west in B quadrant, that south and west in C
quadrant, and that south and east in 0 quadrant. The first digit of a
well number indicates the township, the second the range, and the third
the section in which the well is situated. The lowercase letters a, b, c,
and d after the section number indicate the well location within the
section. The first letter denotes a particular 160-acre tract, the second
the 40-acre tract, and the third the 10-acre tract. These letters also are
assigned in a counterclockwise direction, beginning in the northeast
quarter. If the location is known within the 10-acre tract, three lower­case
letters are shown in the well number. In the example shown, well
number (A-4-5)19caa designates the well as being in the NE\NE\SW\
sec. 19, T. 4 N., R. 5 E. Where more than one well is within a 10-acre
tract, consecutive numbers beginning with 1 are added as suffixes.
Figure 2. --Well-numbering system in Arizona.
5
Regionalization of streamflow data provides an estimate of mean
annual flow at any site on any stream in most of southern Coconino
County (see section entitled "Mean annual flow"). In addition, the prob­ability
of a flood of any magnitude from a given drainage-basin size can
be estimated. For most of the area, equations have been developed by
which the 1-, 3-, and 7-day mean flow volume for a flood having a
50-year recurrence interval may be estimated.
Previous Investigations
The first detailed geologic study in Coconino County was made
in the San Francisco Peaks volcanic field by Robinson (1913). Moore and
others (1960) prepared a geologic map of Coconino County, and Cooley
(1960) described the geology of the San Francisco Plateau. Geology and
water resources of the Navajo I ndian Reservation are described in reports
by Davis and others (1963), Kister and Hatchett (1963), McGavock and
others (1966), and Cooley and others (1964; 1966; 1969). The water
resources of other parts of southern Coconino County are discussed by
Metzger (1961), Cosner (1962), Twenter (1962), Twenter and Metzger
(1963), Levings and Mann (1980), and Levings (1980). Data for many
springs in the area are shown in Feth and Hem (1963) and Johnson and
Sanderson (1968). Rush (1965) and Beus and others (1966) discussed
the relation of geology and surface-water runoff in the Beaver Creek
watershed, which is about 30 mi south of Flagstaff. Studies concerning
the municipal water supplies for Flagstaff and Williams were made by
Akers (1962), Akers and others (1964), and Thomsen (1969). Most of
the hydrologic data collected during this investigation were presented by
McGavock (1968); selected data collected from 1968 to 1975 are included in
this report.
Acknowledgments
The authors gratefully acknowledge the assistance and coopera­tion
of the well owners and drillers in the area. Valuable information
concerning municipal water supplies was provided by H. F. Dunham and
J. L. Rawlinson, Water and Sewer Department, city of Flagstaff; R. B.
Stinson, city of Winslow; and M. B. McCutchan, Arizona Water Company.
W. J. Breed, Museum of Northern Arizona; J. R. Scurlock, State of
Arizona Oil and Gas Conservation Commission; and H. E. Brown, U. S.
Forest Service, permitted access to their records. K. M. Reim, Chief
Mining Engineer for Kern County Land Company, provided well records
and geologic maps of the company1s holdings in southern Coconino
County.
GEOGRAPHIC SETTING
Nearly all of southern Coconino County is in the Plateau
uplands water province of Arizona (fig. 1). The dominant topography is
6
the north- and northeast-sloping plateau, which is cut by steep-walled
canyons. Rolling hills, peaks, and cones of volcanic rocks are super­imposed
on the plateau, where altitudes generally are from 5,000 to 7,000
ft above sea level. A 250-mi 2 area near Flagstaff is underlain by volcanic
rocks and is at an altitude of 7,000 to more than 12,500 ft, which is as
much as 6,500 ft above the altitude of the surrounding plateau. The
Mogollon Rim escarpment has a relief of 2,000 to 3,000 ft and terminates
the plateau along its south edge. The steep south-iacing slopes of the
rim form the demarcation line between the Plateau uplands and Central
highlands water provinces of Arizona. Several deeply incised streams
breach the Mogollon Rim and drain southward and westward from the
plateau. The rim, which is the boundary between Coconino and Gila
Counties, is the south boundary of the study area. The study area is
further bounded on the south and southwest by Yavapai County and on
the west by Mohave County. The Colorado and Little Colorado Rivers
form the north and northeast boundaries, respectively, and Navajo
County forms the east boundary.
Most streams that drain the area are tributary to the Colorado
and Verde Rivers (fig. 1), although a few small areas have interior
drainage. The eastern and northeastern parts of the area are drained by
the Little Colorado River and its tributaries; the Little Colorado River
joins the Colorado River in the Grand Canyon. Havasu and Cataract
Creeks drain most of the northwestern part of the area; Havasu Creek is
the lower reach of Cataract Creek and joins the Colorado River near the
west boundary of Grand Canyon National Park. Between the Little
Colorado River and the Coconino-Mohave County line, several small
tributaries drain directly to the Colorado River. Tributaries of the
south-flowing Verde River drain the southwestern part of the area.
The climate is characterized by extreme temporal and spatial
variations in precipitation and temperature. Storms generally move into
the area from the south and southwest. I n general, the amount. of winter
precipitation is about equal to the amount of summer precipitation
(University of Arizona, 1965a, b). Winter storms commonly distribute
low-intensity precipitation over a large area and may last for several
days. Major floods occur when rain falls on snow or when rainfall is
abnormally intense. During July, August, and September, convectional
storms of high intensity but small areal extent and short duration are
common. Less frequently, in late summer, large moist airmasses originate
off the coast of Mexico and deposit heavy rains that last from 1 day to
several days; these infrequent and intense storms cause major floods.
The mean annual precipitation ranges from less than 6 in. along
the Little Colorado River to more than 35 in. along the Mogollon Rim and
on the San Francisco Peaks (fig. 3). The distribution of the precipita­tion
is influenced by the orographic effect of the Mogollon Rim. At the
Sedona Ranger Station at the base of the Mogollon Rim, the mean annual
precipitation is 17.15 in. (Sellers and Hill, 1974, p. 460). About 50 mi
north of the rim at Winslow, which is at about the same altitude as the
Sedona station, the mean annual precipitation is 7.37 in. (Sellers and
Hill, 1974, p. 570) The local orographic effects of the San Francisco
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Figure 3.~-Mean annual precipitation, 1931-60, and mean annual temperature, 1941-70.
/
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10
J""'IoIIa _w. ..,-' \~
...... ---... 12 'f"""'"
• 2, .21
10
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10
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7
E X P LAN A T ION
LINE OF EQUAL MEAN ANNUAL PRECIPITA-.
TION----,-Interval 2, 4, and 5 inches.
Hachured to indicate closed areas
of lower precipitation. Data from
University of Arizona (1965a. b)
WEATHER STATION--Upper number, 21.21 •
is mean annual precipitation in
inches; lower number, 49.7, is
mean annual temperature in degrees
Fahrenheit. Data from Sellers and
Hill (1974)
10
I
10
I
20
I
20
I
30
!
30
I
40 50
! I
40 MILES
I
KILOMETERS
9
Peaks and Bill Williams Mountain cause greater precipitation at Flagstaff,
Fort Valley, and Williams than at about the same altitude at the Grand
Canyon (fig. 3). Mean annual snowfall ranges from less than 10 in.
along the Colorado and Little Colorado Rivers to more than 80 in. in the
areas of highest altitude along the Mogollon Rim and th,e San Francisco
Peaks. The mean annual temperature ranges from about 40°F at altitudes
above 8,000 ft to about 60°F along the Colorado and Little Colorado
Rivers. Mean annual temperatures at selected weather stations in or
adjacent to the study area also are shown in figure 3.
SURFACE WATER
Most of the precipitation in the area evaporates, is transpired
by plants, flows to the Colorado and Verde Rivers, or infiltrates to the
underlying ground-water reservoirs. A small part of the precipitation is
stored in natural or manmade impoundments for municipal, livestock, or
recreational use. Nearly all streams in the study area are intermittent
and flow only in response to rainfall or snowmelt; a few streams contain
perennial flow that is maintained by ground-water discharge. A signifi­cant
but unknown amount of streamflow percolates through the streambeds
and recharges ground-water reservoirs.
Mean Annual Flow
Data from 39 continuous-record gaging stations having 5 years
or more of record show the large variation in flow in the area and the
variation in flow at a station with time (table 1). The coefficient of
variation (table 1) is a measure of annual flow variability-the larger the
value, the larger the variability. A zero value would indicate constant
flow. Data collected at crest-stage gaging stations further indicate the
variability of flow and the small amount of runoff. Results indicate that
zero flow occurred in about 50 percent of the years at these sites. The
infrequent flow events typically are less than a few hours in duration.
Additional and more detailed daily streamflow data including monthly and
annual flow totals and low- and peak-flow data are published annually
(U.S. Geological Survey, 1919-60; 1961-75).
A multiple-regression technique was used to regionalize mean
annual flow. Measurements of basin and climatic characteristics, such as
drainage area, slope of the stream, mean annual precipitation, and snow­fall
in gaged basins, are treated as independent variables and are related
to various dependent streamflow characteristics, such as mean annual
flow. A study by Moosburner (1970) using data collected at 104 stream­flow
sites throughout Arizona provided a method for estimating mean
annual flow in part of southern Coconino County on the basis of region­alization
of the data. The data for all streamflow-gaging stations (fig. 4)
in southern Coconino County and adjacent areas were handled in a similar
manner to provide a method for estimating the mean annual flow in most
10 Tab le 1. --Mean flow character; sti cs at conti nuous-record gag; n9 stat; ons
Station
number Station name
09397500 Chevelon Creek below Wildcat
Period of
record
Canyon, near Winslow....... 1947-70
09398000 Chevelon Creek near
Winslow.................... 1917-19,
09398500 Cl ear Creek below Willow
Creek, near Winslow ....... .
09399000 Clear Creek near Winslow .....
1930-33,
1936-72
1947-74'
m~=~g2
09400600 Ri 0 de Fl ag at Fl agstaff.. .. . 1956-60
0940Q850 Upper Lake Mary near
Fl agstaff.. .. . . . .. . . . . . .. .. 1949-70
09401000 Little Colorado River at 1925-51,
Drainage
area, in
square
miles
275
794
321
607
50.4
53.5
Mean flow
Cubic
feet
per
second
49.5
50.3
78.7
77.7
Acre­feet
per
year!
35,860
36,440
57,020
56,290
.15 109
9.21 6,670
Inches
per year
2.44
.86
3.33
1.74
.04
2.34
Grand Falls ................ 1953-59 21,200 253 183,200 .16
09402000 Little Colorado River
near Cameron............... 1948-742 26,500 228 165,200 .12
09404040 Cataract Creek near
Williams................... 1966-72 46.4 3.10 2,250
09503700 Verde River near Paulden..... 1964-742 2,530 33.7 24,420
.91
.18
09503720 Hell Canyon near Williams.... 1966-72 14.9 3.31 2,400 3.02
09503800 Volunteer Wash near
Bellemont .. .-.............. 1966-72 131 3.82 2,770 .40
09504000 Verde River near
Clarkdale.................. 1915-16, 3,520
1917-20
193 139,800 .74
1965-74'
00504500 Oak Creek near Cornville..... 1941-45 357
1949-74'
83.4 60,420 3.17
09505200 Wet Beaver Creek near
Rimrock.................... 1962-74' 111 32.6 23,620 3.99
09505250 Red Tank Draw near
Rimrock.................... 1958-742
09505300 Rattlesnake Canyon near
Rimrock.................... 1958-742
09505350 Dry Beaver Creek near
Rimrock.................... 1961-74'
09505800 West Clear Creek near
Camp Verde................. 1966-74'
U.S. Forest Service
gag; n9 stab ons
Beaver Creek Watershed 1.... 1958-73
Beaver Creek Watershed 2.... 1958-742
Beaver Creek Watershed 3.... 1958-742
Beaver Creek Watershed 4.... 1958-73
Beaver Creek Watershed 5.... 1958-73
Beaver Creek Watershed 6.... 1959-73
Beaver Creek Watershed 7.... 1958-73
Beaver Creek Watershed 8.... 1958-742
Beaver Creek Watershed 9.... 1958~742
8eaver Creek Watershed 10.... 1958-742-
Beaver Creek Watershed 11.... 1959-742
Beaver Creek Watershed 12.... 1959-742
Beaver Creek Watershed 13.... 1959-742
Beaver Creek Watershed 14.... 1959-742
Beaver Creek Watershed 15.... 1963-742
Beaver Creek Watershed 16.... 1963-742
Beaver Creek Watershed 17.... 1963-742-
Beaver Creek Watershed 18.... 1963-742
Beaver Creek Watershed 19.... 1962-742
Beaver Creek Watershed 20.... 1962-742
49.4 7.18 5,200 1.97
24.6 7.29 5,280 4.02
142 37.4 27,100 3.58
241 59.8 43,300 3.37
0.52
.20
.57
0.04
.01
.04
30.5 1.10
10.4 1.00
32.2 1.07
.54 .21 152 5.29
.10 .04 29.0 5.28
0.16 .04 31.5 3.64
3.18 .71 515 3.03
2.82 1.41 1,024 6.82
1.75 .90 649 6.95
.89 .28 205 4.31
.29 .07 49.2 3.14
.71 .36 258 6.81
1.42 .38 274 3.61
2.11 .72 519 4.61
.25 .08 54.5 4.01
.39 .17 126 6.00
.47 .28 205 8.24
.38 .18 132 6.56
16.71 7.58 5,490 6.16
25.75 11.3 8,160 5.94
lBased on water year, October 1 through September 30.
2Active gaging station.
Standard
error, in
percent
14
16
13
102
19
12
18
43
14
29
33
17
11
22
31
27
27
32
35
36
36
26
28
31
27
22
23
28
30
25
25
28
29
27
25
25
27
26
Maximum
yearly
flow, in
acre-feeti
95,490
105,300
201,800
196,500
531
17,500
586,800
815,900
7,750
55,340
5,090
6,040
306,300
173,600
74,500
26,740
21,720
97,940
143,800
140
53
177
608
128
144
2,099
3,465
2,384
872
227
1,046
1,072
2,295
155
426
631
389
19,440
28,810
Minimum
yearly
flow, in
acre-feeV
9,610
5,560
7,620
5,050
18,670
19,340
344
17,330
216
60,960
21,440
6,400
32
100
990
13,330
5.4
.8
.5
.6
78
26
3.7
.2
7.3
28
10
.1
7.3
20
6.0
167
244
eoeff; c; ent
of variation
0.66
.63
.82
.83
2.28
0.82
.72
.93
1.14
.47
.78
.89
.58
.60
.81
1.29
1.11
1.01
.97
1.38
1.49
1.49
1..02
1.14
1.21
1.08
.89
.96
1.16
1.22
1.00
1.00
1.11
1.00
.95
.82
.87
. 97
.94
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-'" TheGep~
,( ~ ..
, """ ) HoI!s
/.-..Q '
I
< ~
\ ~
CfOUMi" 1 ~
p" AL'LEL (
\ ~ - ~ '-; ( '"
~ "' .L
I
J( NORTH
~~
+==t==4=~~--~~~~~.~~~~-~~I='='~~'M~====~~~~==~==~~~~~~~~~~~~~sJ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~::l35°
IE: ~/
6JIO.
"
BASE FROM U.S. GEOL.,OGICAL SURVEY
0/ Over
~~)'7D8~ I
;l
402000
~
503800
10
I I
10
I
Figure 4.--Perennial stream reaches, location of streamflow-gaging stations, and runoff regions in southern Coconino County.
0
I
0
I
11
E X P LAN A T ION
RUNOFF REGIONS
Region 1
Region 2
Region 3
STREAMFLOW-GAGING STATION--Number is
abbreviated station number; see
station number 09402000 on table 1
DISCONTINUED STREAMFLOW-GAGING STATION
NUMBER--Number is abbreviated
station number; see station number
09503800 on table 1
PERENNIAL STREAM REACH--Smal1 reaches
of only local significance are not
shown
10 20 30 40 MILES
I I I J
10 20 30 40 50 KILOMETERS
I I I I I
13
of the study area. As a result of the data analysis, southern Coconino
County was divided into three runoff regions (fig. 4). The applicable
equations for regions 1 and 2 are:
and
where
Region 1:
Region 2:
Q = mean annual flow, in cubic feet per second;
A = drainage area, in square miles;
P = normal annual precipitation on the drainage area,
in inches i and
S = shape factor, defined as the square of the length
of main channel from site to divide, in miles,
divided by the drainage area, in square miles.
The third region is an area largely underlain with volcanic cinders north
of Flagstaff where surface-water runoff may be negligible. A regression
equation could not be defined for this region because data are
insufficient. The regression equations should be used with judgment and
in conjunction with other procedures, such as those recommended by
Moore (1968), and with correlation methods whenever possible.
The Colorado River is almost completely regulated by releases
from Glen Canyon Dam near the Arizona-Utah State line (fig. 1). Tribu­tary
inflow from the Paria and Little Colorado Rivers and some smaller
streams represent the only uncontrolled flow. Before 1963 when regula­tion
by Glen Canyon Dam began, the mean annual flow of the Colorado
River near Grand Canyon for 1922-62 was 16,930 ft3/s and ranged from a
high of 26,840 ft3/s in 1929 to a low of 6,431 ft3/s in 1934. Most of the
flow occurred from April to July from snowmelt in the upper Colorado
River basin. For 1964-74, which included the period when Lake Powell
was filling, the flow averaged 12,840 ft3/s.
The greatest surface-water unit runoff in the study area is
from the Mogollon Rim area where the normal annual precipitation is
greater than 20 in. (fig. 3). Mean annual run6ff of as much as 8.24 in.
has been measured from small high-altitude drainages in the Mogollon Rim
area by the U. S. Forest Service (table 1). Mean annual runoff from
larger watersheds-greater than 10 mi 2-tributary to the Verde River and
the upper reaches of Clear and Chevelon Creeks ranges from 1.97 to
6.16 in. (table 1). Runoff is least in the area of the volcanic cinders
north of Flagstaff, in some of the low-altitude and comparatively flat
parts of the Havasu drainage, and along the Little Colorado River. The
mean annual surface-water runoff in these areas probably is much Jess
than 0.5 in. and may be near zero. The lowest surface-water runoff
measured at a gaging station in the study area-0.04 in./yr-was for Rio
de Flag at Flagstaff (table 1).
14
Flood Peaks
Flood discharges and frequency of occurrence in the area are
reported as peak instantaneous discharges, flood volume for a specified
period of time, and flow duration. These data must be known for proper
design of hydraulic structures, highways, and storage projects; floodway
zoning; and other purposes where consideration of water supply or flood
hazard is a factor.
Flood-peak frequency data for a site commonly are plotted as
peak discharge versus recurrence interval. Recurrence interval is
defined as the average interval of time within which a peak flow of a
given magnitude will be equaled or exceeded once. The probability .of a
flood of a given magnitude occurring in anyone year may be estimated
from a given recurrence interval. For example, if the recurrence interval
of a flood of a given magnitude is 25 years, the probability of it
occurring in anyone year is 4 percent. Although the average frequency
of a flood of a given magnitude can be estimated, the time of its next
occurrence cannot be predicted.
Flood-peak frequencies can be determined directly from flow
records for a specific site where streamflow is gaged. Regionalization of
the data involves combining the frequency curves developed for individual
gaging stations in a region into one frequency curve that would be
applicable to any stream in a region at either a gaged or ungaged site.
By assuming that the data can be regionalized, an inherent assumption of
homogeneity is made with respect to flood-producing characteristics within
the region.
The three hydrologic areas and two flood-frequency regions
defined by Patterson and Somers (1966) that are included in southern
Coconino County are shown in figure SA. The index method is one
method of regionalizing the flood-peak frequency curve. Peak discharges
that have a recurrence interval of 2.33 years (Q2. 33)' which is defined
as the mean annual flood, are utilized in developing two relations. One is
the relation of the mean annual flood to the size of the drainage area from
which the floods originate. The relations for each of the hydrologic areas
are shown in figure 6. The second relation uses the dimensionless ratio
of any discharge to the mean annual flood to relate to recurrence
interval. The relations for the two flood-frequency regions are shown in
figure 7. The combined use of these two relations allows the estimation
of the peak discharge of a flood of any recurrence interval at any stream
site in the region where the flood-frequency relations are defined.
Roeske (1978) used multiple-regression techniques to develop
regional flood-frequency relations based on gaging-station data collected
throughout Arizona. Equations were presented for estimating peak-flow
magnitudes for recurrence intervals of 2, 5, 10, "25, 50, 100, and
500 years (Roeske, 1978, p. 5-7). The study area includes parts of
I
I
I
I
I
I
I
I
I
I
I
I
I
I
I
I
I
I
I!tASE F9I04 U. S. GEI1.OGICN.. 54,R\4EV
~ o
17
WOW H ~ ~~~
I I! I I I I
10 0 10 20 30 40 50 KILCfETERS
I I I ! I I ! f
E X P LAN A T ION
FLOOD-FREQUENCY RELATIONS NOT DEFINED
FLOOD-FREQUENCY REGION
FLOOD-FREQUENCY REGION BOUNDARY
HYDROLOGIC AREA
__ -- HYDROLOGIC-AREA BOUNDARY
STUDY-AREA BOUNDARY
A. Flood-frequency regions and hydrologic areas
of Patterson and Somers (1966, pl •. 1).
Figure 5.--Hydrologic areas and flood-frequency regions in southern Coconino County.
BASE: FROM U.S. GEa...OGICN.. 5t.R'v€V
4
10 to 20 JO 40 MIL.ES
I I I I I I
10 0 10 20 JO 40 50 KIL....OMElERS
, I I I I I I I
E X P LAN A T ION
APPROXIMATE AREA OF HIGH-ELEVATION
FLOOD-FREQUENCY R.EGION
FLOOD-FREQUENCY REGION
FLOOD-FREQUENCY REGION BOUNDARY
STUDY-AREA BOUNDARY
B. Flood-frequency regions of Roeske (1978).
15
o
:z::
o
u
UJ
V)
ex:
UJ
0-
I­UJ
Li.J u..
U- co
30,000 ~--~--~----~----~----~------------
20,000
10,000
5000
a 2000
z....:..
o 1000
oo
...J u..
...J
:3 z:
z:
~
z:
~
LLJ
::£
500
200
NU'-1BERS • 15, 17, AND 18. REFER TO
HYDROLOGIC AREA AS DEFINED BY
PA TTERSa.l MoD SOf.ERS (1966) AND
SHJ\It'N IN F I Gt.RE 5.
100 ~~ ___ ~ _ ~ ___ -L __ ~~ _ ~ ___ ~
30 50 100 200 500 1000 2000 5000
CONTRIBUTING DRAINAGE AREA, IN SQUARE MILES
Figure 6.--Drainage area versus mean annual flood
(Patterson and Somers, 1966, p. 12).
17
18
0 10 0
0
u....J 9 LETTERS. C An) D. REFER TO FLCXD-
...J FREaLENCY REGI~ AS DEFINED BY
c2:: 8 PATTERS()II ~ SOMERS (1966) An)
~ z: SKlIN IN FIGU£ 5. z:
c2:: 7
z:
~ 6 ::E:
0
l- S
LLJ
C!' c::: 4
c2::
:J:
U -til 3 0
u. 2
0
-0 1 I-
~ 0
1.01 1.1 1.5 2 5 10 20 50 100
RECURRENCE INTERVAL, IN YEARS
Figure 7.--Ratio of T-year flood to mean annual flood (Q.2.33)
(Patterson and Somers, 1966, p. 4).
19
Roe~, 5 r~efJion 'l'~--No('thv est pii:\te':IUiHE.":"t i1e'~Jion 3""Cf;"dr'c"d I"K1LHltai'-1
area I R(;)gion 4-~~N(;rtheast plal:(;';,\u af'C~! i and tlli;:~ /'dQli' c-dr~vation r'f.':£1
(ff9. SB).
F Voi(lrnlC::$
1"·-:;r:LH f,tlCe int":lvals\'v;)s (i,!ti;'rmI1·,·~:(:i (·'mn ;'1 f"l::~~! r~(~ 2.~:'} r or'"\ ~l, ~~I i:~ '}!~~ j sol: tj"j (~
The equ:;j(-lorl:' re:Oil.dtINi
f:'~,'qurtt)ons d('t: :JjJpl; !p,-~ to
data frc)m ,:1Tf~an)S In 1;1'18 ~;tudv d
from lhe::lnal'),:;,es l;.ir'e gi\l(";n i
f'LHlvi't l'f:qionsl and ~) ( ~j" (I\!
The '1- f :i .. I ari() 1··daV !Ti: al1
nterval cCln be (":,;,tirna(c,cj few li
w;e of the equaL s in table ~"
1 t:
l~O equ liol-i V\f,~i:; (ic1.. c~rn~;ne(} fc;t' t'f:)~d'~1n 3.
f!O\f~': \/OiKJ,'PC':5 fOJ' ;Li ::}O~~/~..:at· 1'''(::'·CJJr'r'12.rl(>E:
s t ;'''0!::nn ~~ ~ tE~:;'J in nHJ::-.: t {Jf 1, h (~I a r'£-~{: b \'
/\ f lo\v -{J Lu"ation (:~ r~\:'e fo f" d S tf~C~tJf\ i ~,~ i l,(~ ~ ;',; d ct.ntH-d ~I t ~ \i~?~
freqW2.llCV ClIt'VB that ~;!IOVi: Ih:.:' (:l':I,,', Lhnt ri,~cj
clrschargE::s ate cqtJi..1led or' €~) \, .' ~), -1) ~ r
conlbines the f!o\v char~i;:~cter~::}t~ :,.~~ or 1..1 :":t\:'e.:vn ~~it:~~ throu rhe rdn~Jt::' of
d;:.~ch\':H'ge vvit:hc:ut r"t)gar'd 10 ::)(~ ~~t~qui:;'nc<? o!"',';:;cutrcnce cit pr'c;.\iidr~s a
convenient means If)!' compdrin(:' :-.;tIV<'iil"h. T~~e ::;Icipe or th\~ n(H\i~du
cun:e IS indlcdti'Je of the by::Jr'oiQqic <11 ic ch'-1t"acteristk~~, of a
drainage ,wea.
Rapresentative flow-d H'aUoil (LH'\I~'S t'or' seitcctli;d p\~I'enn;Cl! and
intermittent stt'earns in the stUt1y ar',~a are ShOvvTl in figure 8. Chevelon
Creek near Winslow and Oal-<. C reek near Ccwi1vil!~> are perennldl at the
gage sites i this is indicated b" the flat-slope part of the CLwve to thE
I'ight (fig. 8), The intermittedt Sir'eams dt'€ illustrated by t.he steep
slope of the CLwve and the lack of a flat-'slope pa!'t. Although dUI'ation
curves are not available for ~ 11ail intenrdttent stTeams typlcB! of the
northwestern part of the stUG / at'ea r crest-staqe gaging-station data
indicate that flow occurs only boutl percent of the time \.vhen a time
unit of a day is used. The per\ entage of time in most places probably is
less than 1 percent because each flew event encompasses only a few hours
rather than a full day.
Perennial 51. ~ams and Low Flows
Only a few stt~eams ir' :w near the study' area are pei'ennial.
The known perennial reaches :r' shown in fi9lwe 4/ exclusive of the
small perennial spring-fed strealjl~ tributal'Y to the Colorado River in the
Grand Canyon and a few rF j laS of minot' streams of only local
significance. Ground-water' dis··) ~rge is the source of watel' in the
perennial streams.
i i
Table 2.--Regression equations used to estimate 1-, 3-, and 7-day mean flow volumes on ungaged streams
in runoff regions 1 and 2 for a 50-year recurrence interval
I\) o
[Runoff region is shown in figure 4. VI , 50 ,. V3 50 and V7 50 are the highest 1-, 3-, and 7-day mean flow volumes ') ,
that occur on the average of once every 50 years; A is drainage area, in square mi 1 es. Pis mean annual
precipitation in drainage area, in inches. r is maximum 24-hour point rainfall, in inches, having a
recurrence interval of 10 years (U.S. Weather Bureau, 1967). SO is the soil index, which is dimensionless;
the soil index is an index to the capacity of the soil to accept infiltration and is based on soil type, soil
cover, and agriculture practices. An index of 3 generally should be used in southern Coconino County except
in the Grand Canyon area, where 4 should be used and in some parts of the Flagstaff area where the index
is 2]
Region 1
Mean flow, in cubic
feet per se'cond
V
1
,50 = 0.582AO.65r4.34
V
3
,50 = O.331AO.67r4.21
V
7
,50 = 0.254AO.65r4.09
Standard error,
in percent
104
86
74
Region 2
Mean flow, in cubic
feet per second
V
1
,50 = 1.76 A 0.80r-·78(SO)3.68
V3,50 = 1.01 A 0.82 r-. 73(SO)3.56
V
7
,50 = 9.34 x 10-2AO.83pO.97(SO)-0.80r2.62
Standard error,
in percent
67
55
47
20 21
10 \\
~~\ .---1 Red Tank Draw
~\ near Rimrock \\ ." . ".,', .... \~
... '. '\,
~ \
~. \
1 \, \. LJ.J .-..-..f. \\ ~. ::E \~ LJ.J \ . c::: c:t: \ ~.
=> CY' \ \
V) c::: · \ \\ cLJ...J ·· \ \\ CZ l · \\ 0u ··· \ LJ.J · \ V) · \ .~
c::: ·· \ LJ.J · , \ '-, ~ Dak Creek c.. 0.1 ··· , \........ near Cornvi 11 e l- ·· , LJ.J , LJ.J · " ................ l..L.. · , ,
.u... .. ·· ,, . ........ ........ co · \ ......... => ·· , . ......... t ) , \ .........
z , . .........
...... , \ ........
ft , . ........
LJ.J ,
~ <..!) Chevelon Creek below , c::: , c:t: , Wildcat Canyon, near :c Winslow u ,
V) . , ...... \ Cl J ,
0.01 , .
I \
Rio de Flag
at Flagstaff
Chevelon Creek
near Winslow
0.001 L-~~L-L-L-L--L~ _ ~-L~~~~-L _ L-~~~~ _ ~ _ ~
0.01 0.1 0.2 2 10 20 40 60 SO 95 99 99.S 99.99
PERCENTAGE OF TIME INDICATED DISCHARGE IS EQUALED OR EXCEEDED
Figure S.--Flow-duration curves for selected streamflow-gaging sites.
22
The perennial streams in the Little Colorado River drainage in
or near the study area include (1) parts of Chevelon Creek, which has a
low-flow rate of 3,260 acre-ft/yr at the gaging station Chevelon Creek
near Winslow; (2) parts of Clear Creek, which has a low-flow rate of
3,100 acre-ft/yr downstream from the gaging station Clear Creek near
Winslow (Mann, 1976); and (3) the Little Colorado River from Blue Spring
to its mouth, which has a low-flow rate of 161,000 acre-ft/yr. Blue
Spring is the largest of several springs that issue into the Little Colorado
River from about 3 to 13 mi above its mouth . This is the only reach of
the Little Colorado River in the study area that is perennial. Thirteen
discharge measurements made from 1952 to 1967 indicate that little
variation occurs in the total spring flow (Johnson and Sanderson, 1968).
Havasu Spring is the source of perennial flow in Havasu Creek.
The spring is a series of seeps that emerge from the bottom of Havasu
Canyon along several branches of Havasu Creek. The seeps occur in a
quarter-mile reach about 10 mi upstream from the mouth of Havasu Creek.
Discharge measurements made downstream from Havasu Spring since 1950
indicate a nearly constant base flow of about 46,000 acre-ft/yr.
Several spring-fed tributaries to the Verde River, which
include Oak Creek, Wet Beaver Creek, and West Clear Creek, head and
are perennial in a part of the study area. Additional information on
springs in or near the study area is presented by Feth and Hem (1963)
and Johnson and Sanderson (1968).
Quality of Surface Water
Most of the dissolved constituents in streamflow are derived
from reactions of rainfall or snowmelt with minerals on the surface of the
ground or in the ground. A smaller component is contained in the rain
and snow prior to its contact with the ground surface. At the same
sampling site in a stream, concentrations of dissolved solids will be
greater in the base flow than in the floodflow. Owing to the longer
ground-contact time, base-flow water dissolves more minerals than does
floodflow water.
Dissolved-solids concentrations in streamflow during periods of
storm or snowmelt runoff are extremely low in most streams that drain the
area. The concentrations range from 34 to 916 mg/L (milligrams per
liter) and generally are less than 100 mg/L (table 4). The main
dissolved-solids constituents during the high-runoff periods are silica,
calcium, and bicarbonate.
The base flow of the Little Colorado River below Blue Spring
and in the lower reaches of Chevelon Creek contains from 1,870 to
2,600 mg/L or more of dissolved solids (table 4) i the main constituents
are sodium and chloride. Flow of Havasu Creek below the springs
generally has a dissolved-solids concentration that ranges from 380 to 485
mg/L (table 4); the main constituents are calcium and bicarbonate. The
23
chemical quality of the base flow of the Verde River tributaries is
markedly better than that of the Colorado River and its tributaries. The
dissolved-solids concentrations range from 153 mg/L in Wet Beaver Creek
to 220 mg/L in Oak Creek; the main constituents are calcium and
bicarbonate (table 4).
Stream temperatures (table 4) are dependent mainly on air
temperature, size of the stream, and proximity of the measuring site to
the streamflow source. Storm and snowmelt runoff temperatures
probably are closely related to local air temperatures, whereas streamflow
temperatures immediately downstream from 'perennial springs are nearly
constant, especially below springs that are the outflow from large
ground -water reservoi rs.
Streamflow transports disintegrated rock material either in
suspension or as bedload. The sediment load of any stream depends on
the char~cteristics of the drainage basin, such as lithology, vegetal
cover, mean annual precipitation, storm intensity, topography, and type
and degree of development. The sediment yield, which is the volume of
sediment load per unit area, varies widely in the study area and
generally is lowest in the highest altitudes (W. F. Mildner, Soil
Conservation Service, written commun., 1971). Quantitative data are
sparse for most streams, but floodflow in the Little Colorado River at
Cameron transported a total of 2,580,000 tons of suspended sediment on
September 21, 1952 ( Love, 1961, p. 155).
GROUND WATER
Ground water occurs in nearly all the geologic formations that
underlie southern Coconino County and is the major source of reliable
water supplies. Many of the geologic formations are hydraulically
connected and combine to form aquifers. An aquifer is a formation,
group of formations, or part of a formation that contains sufficient
saturated permeable material to yield significant quantities of water to
wells and springs (Lohman and others, 1972, p. 2).
On the basis of subsurface geologic data from wells and test
holes, two major aquifers are delineated in southern Coconino County.
The Coconino aquifer is the uppermost and main source of ground water
in the eastern part of the area. I n the central and western parts of the
area, the Coconino aquifer generally does not contain water. Water
occurs mainly in a sequence of hydraulically connected limestone,
dolomite, and sandstone units that are found at considerable depth below
the units that make up the Coconino aquifer. Because the rocks that
form the deeper aquifer are mainly limestone, the aquifer is informally
referred to as the IIlimestone aquifer. II
In
the Coconino
the Moenkopi
addition to the widespread occurrence of water in
and limestone aquifers, ground water also occurs in
and Chinle Formations, volcanic rocks, and sedimentary
24
deposits. Although these units dq not contain wate
they do provide locally important sources of water mai
livestock use.
Coconino Aquifer
The Coconino aquifer is the main source of ground water in the
eastern part of the study area. West of Flagstaff, the units that make
up the aquifer generally are drained of water. The aquifer consists of
three principal formations, which, in ascending order, are the Supai
Formation of Permian and Pennsylvanian age and the Coconino Sandstone­the
main water-bearing unit in the aquifer-and .the Kaibab Limestone of
Permian age (pI. 1). In the southeastern part near Fossil Creek, the
Naco Formation of Pennsylvanian age underlies and intertongues with the
lower member of the Supai Formation. No wells are known to tap the
Naco, but the Naco is the source of Fossil Springs, which discharge
about 18,000 gal/min of water. In the central part of the area the
Toroweap Formation of Permian age separates the Coconino Sandstone from
the Kaibab Limestone. I n the northwestern part the Hermit Shale of
Permian age lies between the Supai Formation and the Coconino
Sandstone. Where the Toroweap and Hermit are present, they generally
are above the water table.
The Supai Formation is the thickest and most lithologically
variable formation in southern Coconino County. The formation is about
800 ft thick at the west end of the Grand Canyon, 1,750 ft thick along
the Mogollon Rim in Fossil Creek Canyon (Huddle and Dobrovolny, 1945),
and 2,200 ft thick near Winslow. In the northwestern part the Supai is
overlain by the Hermit Shale and consists of alternating beds of silty
sandstone and siltstone.
In the central and southeastern parts of the area, three
distinct members of the Supai have been recognized. The upper member
of the Supai is composed of moderately silty sandstone that in places
intertongues with the overlying Coconino Sandstone. The middle member
IS composed of alternating beds of siltstone and mudstone with some
sandstone, conglomerate, and limestone. The lower member of the Supai
is mainly sandstone, siltstone, and limestone. Part of the lower member
is lithologically similar to and may be the lateral equivalent of the Naco
Formation that underlies the Supai east of Verde Valley (Twenter and
Metzger, 1963, p. 30).
I n the extreme northeastern part bf the area, the upper member
of the Supai is mainly a very fine grained sandstone and silty sandstone
that grades downward into mainly siltstone. The siltstone impedes the
downward movement of water into the underlying limestone aquifer. As
the Supai is traced east and south, however, the siltstone beds grade
laterally into very fine grained sandstone and silty sandstone. The
siltstone beds are fractured along major faults and folds, such as the Oak
Creek and Anderson Mesa faults, the ToJchaco anticline, and the East
"'''~''~
25
Kaibab monocline. The fractures provide a direct hydraulic connection
between the Coconino aquifer and the deeper limestone aquifer, and water
in the Coconino aquifer moves downward into the limestone aquifer. J n
places, such as near Sedona, the Coconino and limestone aquifers
probably function as a single hydraulic unit (Levings, 1980).
In the northwestern part of the area, no wells produce water
from the Supai FormQtion. The sandstone in the upper 500 ft of the unit
however is an important source of water in the rest of the area,
especially near Flagstaff. The alternating beds of sandstone, limestone,
siltstone, and mudstone in the middle and lower members presently are
the chief source of ground water in the Sedona area.
The Hermit Shale is about 930 ft thick near the Grand Canyon,
thins rapidly to the south and east, and is not recognizable near the
towns of Williams or Cameron. The Hermit is composed of very fine
grained sandstone, silty sandstone, and limestone and does not yield
water to wells in the area. The Hermit may perch water in the overlying
Coconino Sandstone in places where the sandstone is commonly drained of
water.
The Coconino Sandstone is the most productive and wide-spread
unit of the Coconino aquifer in southern Coconino County. The Coconino
is a very fine to medium-grained, cross-bedded sandstone that is
moderately to well cemented. The Coconino is about 900 ft thick along
the Mogollon Rim near Pine and near Wupatki National Monument and thins
to about 100 ft thick at the west end of Grand Canyon National Park.
The Coconino Sandstone is only moderately to poorly permeable in the
study area except where it is well jointed or faulted.
The Tbroweap Formation in the Grand Canyon area is composed
of about 375 ft of limestone, siltstone, sandstone, and some gypsum beds.
Southeastward, toward Flagstaff, the Toroweap thins and becomes
principally a sandstone; the formation is not recognizable east of the
Flagstaff area. The Toroweap is rarely water bearing in the study area
except near Grand Canyon Village where the siltstone beds perch water in
overlying sandstone beds.
The Kaibab Limestone is composed of sandy limestone and
dolomite and is uniform in lithology throughout most of the area. The
thickness of the Kaibab generally increases in a northwesterly direction
from about 50 ft near Winslow to 380 ft near the Grand Canyon. J n
places, especially in canyon areas, the Kaibab has been completely
removed by erosion. The Kaibab Limestone generally is highly fractured;
thus, it readily accepts recharge from precipitation and allows downward
percolation of water into underlying formations. The Kaibab generally is
above the water table except for small areas near the Little Colorado
River where it is hydraulically connected with the underlying Coconino
Sandstone. Near Flagstaff, chert beds and dense limestone beds locally
perch water in overlying beds of jointed limestone.
26
Occurrence and Movement of Water
The occurrence and movement of water in the Coconino aquifer
are controlled to a large extent by the lithology, or composition, of the
rock units that make up the aquifer. The occurrence and movement of
ground water in the northwestern and southeastern parts of the study
area are discussed separately because of the difference in lithology and
because the two areas are hydrologically distinct with respect to
ground-water characteristics.
Mogollon Rim-Flagstaff area. --The Mogollon Rim-Flagstaff area
includes the eastern and southern parts of southern Coconino County and
corresponds with the western limit of the Coconino aquifer (pl. 2). The
Coconino aquifer in thi.s area includes the Kaibab Limestone, the Coconino
Sandstone, the Supai Formation, and, in a small area near the Mogollon
Rim, the Naco Formation.
Recharge to the aquifer occurs primarily in the areas of high
precipitation, which generally are at altitudes above 7,000 ft along the
Mogollon Rim. Precipitation in these areas readily infiltrates in outcrop
areas of fractured limestone, sandstone, and volcanic rocks and percolates
downward into the Coconino aquifer.
Ground-water movement in the Mogollon Rim-Flagstaff area is to
the northeast or to the southwest. A ground-water divide, which
approximately coincides with the principal recharge area, occurs near the
Mogollon Rim (pl. 1). Much of the ground water moving southward and
westward from the divide is discharged as springs and seeps along the
Mogollon Rim and provides the source of base flow in the tributaries to
the Verde River. The largest single discharge point, Fossil Springs,
discharges about 18,000 gal/min from the Naco Formation at the base of
the aquifer. Some water in the Coconino aquifer percolates downward
along fracture zones into the underlying limestone aquifer and eventually
discharges to the Verde River.
I n most of the Mogollon Rim- Flagstaff area, water in the
Coconino aquifer moves northeastward away from the ground-water divide
near the Mogollon Rim and generally flows toward the Little Colorado
River (pl. 1). Near the river, however, the direction of movement
changes abruptly to the northwest. This change in direction of movement
is influenced by at least three factors: (1) recharge to the aquifer
occurs along the channel of the Little Colorado River and causes a local
mound that underlies the river; (2) ground water moves into the study
area from Navajo County (Mann, 1976) and then moves northwestward
along the Little Colorado River; and (3) a major discharge area for the
Coconino aquifer is along the faulted East Kaibab monocline and the Mesa
Butte fault system (pl. 1). Ground water percolates downward along this
fault and fracture zone into the underlying limestone aquifer. The
ultimate area of discharge for this water is the group of springs in a
27
10-mile reach in the canyon of the Little Colorado River beginning at Blue
Spring about 13 mi upstream from the mouth.
Ground water in the Coconino aquifer is unconfined in nearly
all the Mogollon Rim-Flagstaff area. In a small area between Winslow
and Leupp, ground water occurs under artesian conditions because the
aquifer is fully saturated and is confined by the overlying Moenkopi
Formation.
Grand Canyon-Williams area. --The Grand Canyon-Williams area
comprises about 6,000 mi2 in the northwestern part of the study area. In
this area the Coconino aquifer includes two formations-the Toroweap
Formation and Hermit Shale-not recognized in the Mogollon Rim-Flagstaff
area and does not include the Naco Formation. The Coconino aquifer is
dry throughout most of the Grand Canyon-Williams area; only three wells
completely penetrate the Coconino aquifer. The area of highest precipita­tion,
and presumably the greatest recharge potential, is near Williams.
However, two deep holes that completely penetrated the Coconino
aquifer--one near Ash Fork and one about 20 mi north of Williams-were
dry during drilling until the Redwall Limestone was penetrated. Records
for an oil test in sec. 35, T. 28 N., R. 1 W., indicate that the aquifer
was penetrated fully, but hydrologic data are not available. The siltstone
beds of the Toroweap Formation and the Hermit Shale are not present in
the area near Williams, and the rest of the Coconino aquifer apparently is
sufficiently permeable to allow downward percolation of ground water into
the underlying limestone aquifer.
Some water is present in the Coconino aquifer in the northern
part of the area near the Grand Canyon owing to the presence of fine­grained
perching beds. Water is perched in the Coconino Sandstone by
the underlying Hermit Shale. The reported saturated thickness of the
Coconino Sandstone in wells drilled into this perched water zone ranges
from about 10 to 120 ft. Most wells however penetrated 50 to 60 ft of
water-bearing sandstone above the Hermit Shale. Near Tusayan, 6 mi
south of Grand Canyon Village, several wells reportedly yield from 0.5 to
4.5 gal/min from fractured limestone interbedded with siltstone in the
Toroweap Formation.
Availability of Water
The depth to water in the Coconino aquifer in the Mogollon
Rim-Flagstaff area ranges from about 75 ft near Winslow to about 2,500 ft
below the land surface north of Flagstaff. The formations that compose
the Coconino aquifer are dry in most of the Grand Canyon-Williams area;
deep wells tap the limestone aquifer in which the depth to water is
believed to be at least 3,000 ft below the land surface. Near Cataract
Creek and Tusayan where the Coconino aquifer contains perched water,
the depth to water is about 950 ft and 550 ft below the land surface,
respectively.
28
Well yields from the Coconino aquifer range from about
1 gal/min where the sandstone has a high degree of cementation and the
saturated thickness is a few tens of feet to about 1,000 gal/min where the
aquifer is extensively fractured and has a saturated thickness of more
than 250 ft. The yield of a properly constructed well depends on the
saturated thickness and the hydraulic conductivity of the aquifer near the
well site. The hydraulic conductivity is a function of the degree of
interconnection of open space in the aquifer material. Some of the open
space is between grains in sandstone aquifers, but cracks and fissures
created by faulting and jointing increases the hydraulic conductivity in
the Coconino aquifer.
The city of Flagstaff well fields at Woody Mountain and at Lake
Mary are in or near fault zones; these wells yield from 200 to 1,000
gal/min and are some of the most productive wells in southern Coconino
County. The fault zones also may provide a highly permeable drain for
ground water. Sterling Spring at the head of Oak Creek Canyon is on
the Oak Creek fault and its flow is maintained by ground-water discharge
from the Coconino aquifer.
Chemical Quality of Water
In most of the study area, water in the Coconino aquifer
contains less than 500 mg/L of dissolved solids and is suitable for most
uses. I n the southern and central parts of the Mogollon Rim- Flagstaff
area, the dissolved-solids concentrations in the water range from about
100 to 500 mg/L (pl. 2), and the principal constituents are calcium and
bicarbonate. In the northern part of the Mogollon Rim-Flagstaff area,
near the Little Colorado River, the water contains from 500 to as much as
7,640 mg/L dissolved solids; the principal constituents are sodium and
chloride. Chemical analyses of the water from many of the wells in the
area were published by McGavock (1968). The ranges and median values
of the major dissolved constituents are shown in table 3; analyses of the
water from selected springs and wells also are included in tables 5 and 6.
Tab 1 e 3. --Range and med; an va 1 ue of di ssa 1 ved canst i tuents ; n water from se 1 ected aquifers
[Analytical results in milligrams per liter except as indicated]
Iron Specific
(Fe) Magne- Potas- Bicar- Fluo- Dis- conduct-
Aqui fer Silica in solu- Calcium Sodium Sulfate Chloride Hardness ance (5;02) ticn at (Ca) sium (Na) sium bonate (50
4
) (Cl) ride solved as CaC0
3
(m;cro- pH
time of (Mg) (K) (HC0
3
) (F) solids mhos at
analysis 25°C)
Va 1 can; crocks
Range ........... 20-67 0.0-0.14 12-82 6.8-24 2.8-17 84-262 3-34 2-44 0.0-0.4 124-324 70-282 174-623 6.8-8.1
Median value .... 37 0.00 2.25 11 8.6 124 10 8 0.2 160 100 242 7.2
Number of
analyses ..... . 14 11 16 16 16 16 16 16 16 14 16 16 14
Cocon; no aqui fer
Range .......... . 5.2-56 0.00-0.18 14-229 4.1-96 0.7-2,600 66-890 0.0-667 1-4,200 0.0-1.0 66-7,640 52-834 107-12,900 6.8-8.2
Median value _, .. 13 0.01 76 40 29 240 134 51 0.2 551 353 846 7.5
Number of
analyses ...... 97 62 130 129 123 119 120 123 127 112 122 115 95
29
The general distribution of totaf dissolved solids in ground water in
the Coconino aquifer is shown on plate 2. In some areas, specific­conductance
values were used to estimate dissolved-solids concentrations.
Specific conductance is a measure of the ability of ions to
conduct an electrical current and is a general indication of the amount of
dissolved material in the water. An estimate of the dissolved solids can
be made by multiplying the specific conductance by a factor that
generally ranges from 0.55 to 0.75. On the basis of 108 measurements of
both parameters in the study area, the ratio of dissolved solids to
specific conductance in water from the Coconino aquifer is 0.60.
In the Mogollon Rim-Flagstaff area, ground water is mostly of
the calcium magnesium bicarbonate type and generally contains less than
500 mg/L dissolved solids (pl. 2). The calcium, magnesium, and bicar­bonate
are derived from recharge areas near Flagstaff and along the
Mogollon Rim where the water percolates downward through the Kaibab
Limestone and then moves northeastward or southwestward through sand­stone
that contains little soluble material. The chemical quality of the
water is fairly uniform except for that in an area that extends about 5 to
20 mi southwestward from the Little Colorado River where a sodium
chloride type water dominates (pl. 2). The source of the sodium and
chloride is halite deposits in the Supai Formation 10 to 80 mi east of the
study area (Akers, 1964, p. 80; Mann, 1976, p. 17).
The chemical quality of water does not change significantly with
depth of penetration into the Coconino aquifer in the southwestern
three-quarters of the Mogollon Rim- Flagstaff area. I n Navajo County east
of the study area, the chemical quality of water generally deteriorates
with depth in areas where the aquifer contains water of a sodium chloride
type (Mann, 1976). Along the Little Colorado River where sodium
chloride water is present, a similar deterioration with depth probably
occurs (pI. 2).
During this study, samples of water from the Coconino aquifer
were collected at 14 wells that had been sampled 10 to 33 years
previously. No significant change in chemical quality with time was found
except in four of the wells in the Winslow municipal well field (table 6).
The principal change in the quality of the water from these wells was an
increase in the sodium and chloride concentrations. Analyses of water
from city of Winslow well No. 1 collected in 1953 and again in 1966
indicate an increase in dissolved solids from 531 to 1,040 mg/Li the
sodium concentration increased from 79 to 249· mg/L, and the chloride
concentration increased from 92 to 410 mg/L. Similar changes in water
quality occurred in three other wells. I n the fifth well no change in
quality was noted. The reason for the changes in water quality is not
known. It is postulated, however, that the relatively heavy pumping is
causing saline water to move into the well field, either vertically from
greater depths in the aquifer or from the east and northeast as a result
of local alteration of the regional hydraulic gradient. The chemical
quality of water in this area may continue to deteriorate as a result of
the influence of this local cone of depression.
30
Limestone Aquifer
The limestone aquifer consists of several hydraulically connected
limestone, dolomite, sandstone, and shale units. The units, in ascending
order, include the Tapeats Sandstone, Bright Angel Shale, and Muav
Limestone of Cambrian age; the Temple Butte Limestone, an unnamed
limestone unit, and the Martin Formation of Devonian age; the Redwall
Limestone of Mississippian age; and an unnamed limestone unit of
Pennsylvanian age (pl. 1). In most of the area, the Redwall Limestone is
the uppermost unit of the aquifer and is about 2,500 ft below the land
surface. The unit is exposed in the Grand Canyon, along the Mogollon
Rim, and in a small area west of Aubrey Valley. The combined thickness
of the units that make up the aquifer generally increases from southeast
to northwest. Three of the units included in the aquifer are present
only in parts of the area. The unnamed limestone units of Devonian and
Pennsylvanian age are present in and near the Hualapai Indian
Reservation, and the Temple Butte Limestone is present in the eastern
part of the Grand Canyon.
Occurrence and Movement of Water
The limestone aquifer underlies all of southern Coconino
County but crops out only in the extreme northern and western parts of
the area. Thus, most of the water in the aquifer is derived from the
downward movement of water from the overlying Coconino aquifer. I n the
eastern part of the area, a thick sequencd\ of siltstone in the overlying
Supai Formation impedes the downward movement of water from the
Coconino aquifer. In the central part of the area, however, the Supai is
largely a very fine grained sandstone interbedded with siltstone. The
sandstone, particularly where fractured, is more permeable than the
siltstone and allows the water to move downward. Much of the water
probably moves downward into the limestone aquifer along major fracture
zones, such as the Oak Creek fault and East Kaibab monocline, and
possibly along the Mesa Butte fault system (pl. 1).
Storage and movement of water is primarily in fractures and
solution channels in the carbonate rocks-mainly limestone and dolomite.
Water is also stored· in fractures and intergranular pore spaces in the
Tapeats Sandstone and in sandstone beds in the other units. In the
northern part of the study area, the Bright Angel Shale at the base of
the carbonate rocks in the aquifer and above the Tapeats Sandstone
impedes the downward movement of water. I n the Grand Canyon many
springs issue from solution cavities in limestone and dolomite that overlie
the Bright Angel Shale.
The limestone aquifer may be nearly or completely saturated in
most of the area east of Flagstaff where the lower part of the overlying
Coconino aquifer is saturated. Water in the limestone aquifer may be
confined in places by siltstone in the overlying Supai and Naco Formations
31
but probably is unconfined in most or all the area between Williams and
the Grand Canyon. I n the Sedona area, the Coconino and limestone
aquifers are hydraulically connected in highly fractured areas such as the
Oak Creek fault zone and combihe to form a regional pquifer (Levings,
1980) .
The direction of ground-water movement in the limestone aquifer
can be only inferred from points of spring discharge and from wells south
of the study area. A large part of the ground water probably moves
northward toward· springs along the Little Colorado and Colorado Rivers
and Havasu Creek. South of Williams, ground water probably moves
southward toward discharge areas along the Verde River. The location of
the ground-water divide in the western part of the area is unknown
owing to the extreme paucity of data; however, the continuance of the
limestone aquifer is assumed. The principal discharge points of the
limestone aquifer are Havasu Spring along Havasu Creek and springs in a
10-mile reach in the canyon of the Little Colorado River beginning at Blue
Spring about 13 mi upstream from the mouth. Blue Spring and the other
springs along the Little Colorado River have a combined flow of about 220
ft3/s or about 100,000 gal/min. A large part of this flow however
represents ground water from the Coconino aquifer, which moves down­ward
into the limestone aquifer through the sandstone and fractured
siltstone of the Supai Formation.
Havasu Spring is about 10 mi above the mouth of Havasu Creek
(pl. 2) and discharges about 64 ft3/s or about 29,000 gal/min (Johnson
and Sanderson, 1968, p. 17) from the unnamed limestone unit of
Pennsylvanian age at the top of the limestone aquifer. The altitude of
the springs is about 3,250 ft, which is nearly 1,000 ft below the bottom
of any water well in the northern part of the area. A significant amount
of ground water also may move out of the area to the south. The base
flow in the Verde River increases by about 50 ft3/s in a 25-mile reach
south of Williams. A large but unknown part of this water may be
discharging from the area north of the river.
Blue Spring may be associated with small faults· below the foot
of the East Kaibab monocline. Cooley (1976, p. 9) concluded that
ground-water movement occurs through the highly fractured zone along
and near the East Kaibab monocline. Other faults in the study area,
especially the Aubrey, Toroweap, and Hurricane faults, may exert a
similar influence on local ground-water conditions.
Availability of Water
I n most of southern Coconino County, ground water in the lime­stone
aquifer is beyond an economical well depth for most purposes. The
Redwall Limestone is 2,500 to 3,000 ft below the land surface in most of
the area east of Flagstaff .. Because water generally is available in over­lying
shallower units, few wells penetrate the limestone aquifer. In most
of the western part, the top of the Redwall Limestone is about 2,200 to
32
2,500 ft below the land surface. The Redwall and some of the other
carbonate units that overlie the Bright Angel Shale may be dry in much
of the area. Depth to water in the limestone aquifer therefore is
expected to be about 3,000 ft below the land surface throughout most of
this part of the study area. Between Chino Point and the Mohave County
line where the units that form the aquifer crop out, depth to water
ranges from 625 ft below the land surface near Chino Point to about
800 ft at Pica, which is south of the study area in Aubrey Valley.
The yields of wells that penetrate the limestone aquifer are
expected to be highly variable and unpredictable from place to place.
Where the limestone and dolomite of the aquifer are relatively
unfractured, the hydraulic conductivity is low and well yields may be
25 gal/min or less. Where the limestone and dolomite are fractured,
especially if the fractures are enlarged by solution, the hydraulic
conductivity is high and well yields of 1,000 gal/min or more are possible.
In 1976, only one well in southern Coconino County was with­drawing
water from the limestone aquifer. This well, about 20 mi north
of Williams, produced about 5 gal/min of water from the Redwall Limestone
at a depth of 2,800 ft. After the well was deepened to the Tapeats
Sandstone, about 20 gal/min of water was produced from a pumping level
of about 3,000 ft below the land surface. At Pica, several wells
reportedly yield 50 to 145 gal/min of water from the limestone aquifer.
Southwest of Sedona, some wells penetrate the Redwall Limestone at a
depth of about 1,000 ft. Water levels in these wells range from 600 to
800 ft below the land surface; well yields are reported to range from 20
to 1,000 gal/min.
Chemical Quality of Water
The water from springs that discharge from the limestone
aquifer along Havasu Creek, the Colorado River, and tributaries of the
Verde River generally is of acceptable chemical quality for most uses.
The dissolved-solids concentrations range from 282 to 623 mg/L, and the
principal constituents are calcium, magnesium, and bicarbonate (table 5).
The dissolved-solids concentrations in the water from two wells that
penetrate the aquifer west of Sedona were 355 and 451 mg/L (McGavock,
1968, p. 44). The water from other wells that penetrate the limestone
aquifer southwest of Sedona and south of Aubrey Valley is acceptable for
public, domestic, and stock use. Levings (1980) showed that the
dissolved-solids concentrations of water from wells that tap the Redwall
Limestone generally are less than 500 mg/L; analyses are not available for
wells south of Aubrey Valley. The water from the well about 20 mi north
of Williams that taps the limestone aquifer is unfit for most uses. Specific
conductance of the water is 20,200 micromhos, and the dissolved-solids
concentration is 12,400 mg/L; sodium and chloride are the major
constituents (table 6). Most of the water is produced from the upper
part of the Tapeats Sandstone.
33
Springs that discharge from the limestone aquifer in the lower
reaches of the Little Colorado River yield water in which the dissolved­solids
concentrations range from 2,320 to about 24,380 mg/L (table 5).
The principal constituents of the water from Blue Spring are sodium,
calcium, bicarbonate, and chloride. The ratio of sodium chloride to
calcium bicarbonate in the water downstream from Blue Spring increases
until, at a point 3.1 mi above the mouth of the Little Colorado River, the
water is predominantly of the sodium chloride type. Si-Pa-Po Spring
(pI. 1) discharges water that contains 24,380 mg/L dissolved solids,
principally sodium and chloride. Several small "salt springsll issue from
the Tapeats between Blue Spring and mile point 3.1. The source of the
sodium chloride probably is the halite deposits in the Supai Formation,
which are 10 to 80 mi east of the southern Coconino County area.
Other Aquifers
In places, ground water can be obtained from units that overlie
the Coconino aquifer. The Moenkopi and Chinle Formations, volcanic
rocks, and sedimentary deposits locally will yield quantities of water
adequate for domestic and livestock use. The occurrence and quantity of
water that can be developed cannot be ascertained on the basis of areal
distribution of the units nor on existing data but are dependent on the
lithology of the unit, the presence of fractures, and the lithology of the
underlying formations. If the underlying formations are permeable
sandstone or fractured limestone, the water generally moves downward
into the Coconino or limestone aquifers. If the units are underlain by
siltstone, which is relatively impermeable and impedes the downward
movement of water, the units may contain perched ground water.
Moenkopi and Chinle Formations
The Moenkopi Formation includes an interbedded sequence of
siltstone, mudstone, silty sandstone, and gypsum. The Moenkopi is
overlain by the Chinle Formation, which is mainly siltstone and mudstone
with sandstone and conglomerate near the base (pl. 1). The combined
thickness of the Moenkopi and Chinle Formations of Triassic age is about
800 ft.
The Moenkopi and Chinle Formations generally are not water
bearing but yield some water to wells in three small areas. Three wells
in the Slate Mountain-Cedar Ranch area extend through volcanic rocks
into sandstone that may be part of the Chinle Formation. No change in
water level was reported after drilling through the volcanic rocks,
therefore the sandstone probably is water bearing and is hydraulically
connected < to the overlying volcanic rocks. Several wells near Fort Valley
are reported to yield 5 to 15 gal/min from fractured silty sandstone in the
Moenkopi Formation. Northwest of Winslow, several wells yield water from
the Moenkopi; reported yields range from 1 to 20 gal/min. The Moenkopi
34
and Chinle may yield water in other places, but subsurface data are
inadequate to assess this possibility.
One chemical analysis of wG)ter from the Chinle Formation was
available and none for water from the Moenkopi Formation. The water
sample from the Chinle is from a dug well in the extreme northeastern
part of the study area-well (A-27-10)6abc. The dissolved-solids concen­tration
in the water is 766 mg/L, and the major constituents are sodium,
bicarbonate, and sulfate (McGavock, 1968, table 4). Water from wells
thought to penetrate the Chinle and Moenkopi Formations in the Fort
Valley and the Slate Mountain-Cedar Ranch areas is reportedly of accept­able
chemical quality for domestic use. Water from the Moenkopi Forma­tion
near Winslow, where the Moenkopi contains gypsum beds, is reported
to be of unacceptable chemical quality and normally is cased out of wells.
Volcanic Rocks
The volcanic rocks consist of basalt flows, cinder cones and
beds, and tuff beds. These rocks are as much as 1,000 ft thick,
excluding the volcanic mountains such as San Francisco Peaks and Bill
Williams Mountain. The occurrence and availability of water in the vol­canic
rocks are extremely variable and unpredictable. Some of the
variation may be due to seasonal recharge, differences in well-drilling and
construction methods, and to a limited extent, the techniques used to
estimate the well yields. Much of the variability however is due to the
extent of local fracturing in the rocks and to the openness of the
fractures.
About 50 wells have been drilled into volcanic rocks in the
Fort Valley area near Flagstaff. Well yields range from 0.5 to about
15 gal/min during sustained pumping. Well depths generally are from 100
to 200 ft, arid water levels are from 20 to 170 ft below the land surface.
Six producing wells have been drilled into volcanic rocks in the Slate
Mountain-Cedar Ranch area. Water levels in these wells are from 85 to
375 ft below the land surface, and well depths are from 112 to 450 fti
well yields reportedly range from about 10 to 100 gal/min. Water supplies
have also been developed from volcanic rocks near Mormon Lake, in
Spring Valley, and at the Navajo Army Depot at Bellemont. Generally,
the wells are less than 250 ft deep and produce 1 to 20 gal/min of water.
Water samples from 14 wells that tap only the volcanic rocks
contain from 124 to 324 mg/L of dissolved solids. Calcium and bicar-bonate
are the dominant ions (table 5).
Sedimentary Deposits
The sedimentary deposits include alluvial deposits and glacial
moraine and outwash. They are composed of silt, clay, sand, and gravel
35
and boulders of Quaternary and Tertiary age. The greatest known
thickness of the deposits is in Aubrey Valley where an oil-test hole
penetrated 420 ft of sand, gravel, and clay. I n most places, however,
the deposits are from 50 to 100 ft thick.
The sedimentary deposits are an important source of ground
water in three places-the I nner Basin on the northeastern side of the
San Francisco Peaks, Munds Park about 20 mi south of Flagstaff, and the
northern part of Aubrey Valley.. Minor amounts of ground water are
withdrawn at scattered places for livestock and domestic use. Because
the water is derived totally from local precipitation or runoff that
infiltrates downward into the thin narrow alluvial deposits along major
stream channels, these supplies generally are not reliable for sustained
use, especially during prolonged dry periods.
The Inner Basin of San Francisco Peaks is a glacially carved
valley that is partly filled by glaciofluvial deposits of sand, clay, and
boulders. Water from springs and wells in the I nner Basin is used by
the city of Flagstaff as a part of the municipal supply. The depth to
water in the I nner Basin is from zero to about 200 ft below the land
surface and is subject to large seasonal fluctuations. The more permeable
deposits yield as much as 500 gal/min to wells from depths of 300 to
500 ft.
At Munds Park, clay, sand, and gravel have filled a valley
incised in the volcanic rocks. Several wells that penetrate mainly sand
and gravel have produced 100 to 400 gal/min for several days or weeks.
Most of the wells however yield about 50 gal/min and some holes that
penetrate mainly clay yield little or no water. Water levels in Munds Park
are from about 80 ft to as much as 150 ft below the land surface
depending on location, time of year, and precipitation conditions. Large
fluctuations in water levels can be expected owing to the seasonal
demands and the seasonal recharge conditions. The hydrograph of the
water level in well (A-18-7)15ccb1 in this area is included in figure 9.
Aubrey Valley contains the largest volume of sedimentary
deposits in the study area. Only deposits in the north end of the valley
are known to be water bearing. Five wells in that area yield usable
quantities of water; the largest reported yield was 30 gal/min near
Frazier Wells. Water levels in the five wells ranged from 47 to 422 ft
below the land surface. An oil-test hole-(B-25-8)34aa-penetrated 420 ft
of clay, sand, and gravel in southern Aubrey Valley but no water was
reported at that depth. The sedimentary deposits may be dry in much of
the central and southern parts of Aubrey Valley.
Water samples were collected from the five wells that yield water
only from sedimentary deposits. The dissolved-solids concentrations in
water from four of the wells range from 202 to 388 mg/L and average
298 mg/L (McGavock, 1968, table 4). The principal constituents in the
water are calcium and bicarbonate. The water from well (B-27-6)1adc
contains 2,220 mg/L dissolved solids, of which about 1,970 mg/L are
calcium and sulfate. The alluvial deposits at this site contain some thin
80
36
100
(A-18-7)15ccb1
120 Well depth: 184 ft
All uvi urn
140
160
w u 260 I I I I I ~
LL- _~~t.i!!,~~~<!. ~ 0:::: :::> (A-24-5) l1cdb
(/) 280 f- - Well depth: 292 ft
Cl z: Volcanic rocks
~
-l
3: 300 I I I I I
0
-l
W
co 260 l- I I I I I
w
w ---E~tirn~t~d--=-~ (A-18-14)13abd3
lJ.. City of Wi ns 1 ow z: 280 !- - Well depth: 293 ft ~
~ Coconino aquifer
0::::
w I I 1 I- 300
~
3:
0 1210 I-
:r: (A-21-6)35cba I-
0... w City of Flagstaff-Woody Mountain Cl 1230 Well depth: 1,600 ft
Coconino aquifer
1250
560
580 (A-20-8)18bbb
City of Flagstaff-Lake Mary
Well depth: 1,206 ft
600 Coconino aquifer
620
0 L.(") 0 L.(") 0 L.(") 0
L.(") L.(") 1.0 1.0 ,...." ,...." co 0'\ 0'\ 0'\ 0'\ 0'\ 0'\ 0'\
r-I r-I r-I r-I r-I r-I r-I
Figure 9.--Water levels in selected wells.
37
beds of gypsum that are the source of the large concentrations of
dissolved solids in the water.
DEVELOPMENT OF WATER RESOURCES
Water-resources development in southern Coconino County has
been slight. The principal use of water in the area is for municipal
supplies for Flagstaff and Winslow. Most of the major industries in the
area are served by city water systems, and their consumption is included
in the estimate of municipal use. Domestic and livestock wells account for
a sma" part of the total use. Agricultural use is minimal i the only crop­land
and pasture in the study area are a few miles northeast of Flagstaff.
Total water use in southern Coconino County from surface-water and
ground-water sources is estimated to have been slightly less than 8,000
acre-ft in 1975.
Ground-water development generally is limited by the great
depth to water and by the low yields of we"s. I n some areas, the
chemical quality of the water may restrict development for certain uses.
The total ground-water production from a" aquifers in 1970 was estimated
to be 2,600 acre-ft. Estimated ground-water withdrawal in 1975 was 5,200
acre-ft. Most of the ground water withdrawn in southern Coconino
County is from the municipal we" fields near Flagstaff and Winslow.
Water levels in the Winslow we" field and Flagstaff we" fields near Woody
Mountain and Lake Mary have remained relatively stable. Large water­level
fluctuations occurred in the nonpumping wells (fig. 9), but this
probably is due to the effect of nearby or recent pumping.
Water levels in the aquifers in southern Coconino County have
not been seriously affected by historic ground-water withdrawal's. The
volume of ground water in storagE;! in the study area probably is between
100 and 200 million acre-fti thus, withdrawal at the estimated 1975 rate
should not result in long-term depletion of the system except possibly on
a local basis such as in the municipal we" fields.
The development of surface-water resources is hindered by
the economic considerations of transporting water over long distances and
by prior appropriation of water by downstream users. I n southern
Coconino County more than 4,200 acre-ft of surface water was used for
non recreational purposes in 1970. The estimated total surface-water use
in 1975 was 2,500 acre-fti the city of Flagstaff used about 2,200 acre-ft,
and the city of Williams used less than 300 acre-ft. Annual ,use of
surface-water resources can be extremely variable. Most impoundment
structures are constructed on ephemeral streams that flow only in
response to rainfall and snowmelti the available supply is dependent
entirely on precipitation.
Leakage from surface-water reservoirs is a major problem in the
study areai the land surface commonly is underlain by permeable volcanic
rocks or limestone, and many drainages follow zones of broken permeable
38
rocks. Leakage occurs from Kaibab Lake and Dogtown Reservoir-the
major reservoirs for the city of Williams water supply (Thomsen, 1969).
Dogtown Reservoir was lined with plastic in 1971 in an attempt to
decrease leakage. Data collected by the Geological Survey subsequent to
the lining of the reservoir indicates that the lining has been effective.
Efforts were underway in 1976 to seal Kaibab Lake. Seepage from Upper
Lake Mary, which is the principal source of municipal water for the city
of Flagstaff, was 42 percent, or about 3,200 acre-ft/yr, of the total
reservoir inflow during 1950-71 (J. W. H. Blee, U.S. Geological Survey,
written commun., 1973).
The impounding of surface water for recreational purposes has
increased rapidly since 1963. Six reservoirs constructed since 1963 in
the headwaters of Clear and Chevelon Creeks have a total controlled
storage capacity of more than 27,000 acre-ft. Blue Ridge Reservoir,
which is the largest of the six reservoirs, has a usable storage capacity
of 15,000 acre-ft. This reservoir is used partly as a holding basin for
diversion of water south to the East Verde River. During 1966-73, these
diversions averaged 11,400 acre-ft/yr (U.S. Geological Survey, 1961-75).
The water supply for the city of Flagstaff is obtained primarily
from surface-water storage in Upper Lake Mary, but a significant part of
the supply is obtained from other sources. Springs and infiltration
galleries in the Inner Basin of the San Francisco Peaks have been used
by the city since 1900, and shallow wells in the Inner Basin have been
used since 1968. Deep wells that tap the Coconino aquifer have been
used since 1956 to supplement the city's water supply. During 1956-70,
the city obtained about 65 percent of its water supply from Upper Lake
Mary, about 20 percent from springs in the Inner Basin, and about 15
percent from the Woody Mountain well field. The amount of water
obtained from each source has varied greatly from year to year. Since
1970, a well field at Lower Lake Mary has been an added source of water
for municipal supply. Total municipal water use by the city of Flagstaff
in 1975 was about 5,500 acre-ft.
The city of Winslow is in Navajo County but obtains its entire
water supply from five wells in Coconino County about 8 mi southwest of
the city. Municipal water consumption in Winslow increased from about
1,270 acre-ft in 1956 to about 1,500 acre-ft in 1975. Ground water in
storage in the Coconino aquifer in and near the Winslow wel I field is
sufficient to supply many times the current demand. The chemical quality
of the water from four of the municipal wells however has deteriorated
gradually, and the city may need to seek other sources of water in the
future.
The water supply for the city of Williams is obtained from six
reservoirs, which have a total controlled storage capacity of about 2,800
acre-ft. Three reservoirs-Dogtown, Kaibab, and Cataract-contain 85
percent of the storage capacity. The use of water by the city is
estimated to be less than 300 acre-ft/yr for 1963-75. Despite this
relatively low consumption, the reservoir storage is often insufficient to
39
meet the demand because of high seepage losses in the reservoirs
(Thomsen, 1969).
The water supply in the Sedona area is primarily from wells
owned by private water companies or individuals. Most of the wells are
west of the study area in Yavapai County. An estimated 1,300 acre-ft of
water was pumped from the wells in the Sedona area in 1975; no depletion
of the ground-water system was occurring.
SUMMARY
Southern Coconino County includes about 10,600 mi2 in the
Colorado River basin in north-central Arizona. The topography includes
rolling high plateaus, deeply incised canyons, and rugged mountains.
The areal distribution of precipitation is dependent on altitude and
orographic effects; mean annual precipitation in the study area ranges
from about 6 to 35 in.
Mean annual surface-water runoff is a small percentage of mean
annual precipitation; most precipitation is lost to evapotranspiration or
infiltration. Nearly all the streams in the study area are intermittent.
Streamflow generally is of acceptable chemical quality for most uses in
intermittent and perennial streams during periods of storm and snowmelt
runoff; dissolved-solids concentrations commonly are less than 200 mg/L.
Dissolved solids in low or base flows in the perennial streams that drain
the area range from 200 to 2,600 mg/L.
Ground water occurs chiefly in two aquifers-the Coconino
aquifer and a limestone aquifer. The Coconino aquifer is the most highly
developed aquifer but does not underlie the entire study area; about 75
percent of the ground water pumped in southern Coconino County comes
from this aquifer. Well yields range from about 1 to 1,000 gal/min.
Depth to water ranges from about 75 ft near Winslow to about 2,500 ft
north of Flagstaff. The chemical quality of the water generally is good;
dissolved-solids concentrations commonly are less than 500 mg/L. The
limestone aquifer contains water throughout the study area and has the
greatest potential well yields but generally is not tapped because the
required well depth exceeds 2,500 ft in most places.
In places, ground water also is obtained from the Moenkopi and
Chinle Formations, volcanic rocks, and sedimentary deposits. These units
yield water of suitable chemical quality for livestock and domestic use in
the central part of the area, mainly near Flagstaff, Fort Valley, the Inner
Basin of the San Francisco Peaks, and Munds Park. Although the units
do not contain water in large areas, they typically contain water at
depths of less than 300 ft, and well yields of 10 to 50 gal/min are not
uncommon.
The development of ground-water or surface-water resources
in southe.rn Coconino County has not been extensive. Ground-water
40
development generally is hindered by the great depth to water and by
the relatively low yields of existing wells. The development of
surface-water resources has been hindered by the economic
considerations of transporting water over long distances and by prior
appropriation of water by downstream users. In 1970 total ground-water
production from all sources was about 2,600 acre-ft, and about 4,200
acre-ft of surface water was used for non recreational purposes. In 1975
ground-water production was about 5,200 acre-ft, and about 2,500 acre-ft
of surface water was used for non recreational purposes. Between 100 and
200 million acre-ft of ground water is estimated to be in storage in the
study area. Ground-water withdrawals are not resulting in depletion of
water in the system or large declines in water levels.
SELECTED REFERENCES
Akers, J. P., 1962, Relation of faulting to the occurrence of ground
water in the Flagstaff area, Arizona, in Geological Survey
research 1962: U.S. Geological Survey Professional Paper
450-B, p. 97-100.
------
1964, Geology and ground water in the central part of Apache
County, Arizona: U.S. Geological Survey Water-Supply Paper
1771, 107 p.
Akers, J. P., Cooley, M. E., and Dennis, P. E., 1964, Synopsis of
ground-water conditions on the San Francisco Plateau near
Flagstaff, Coconino County, Arizona: U.S. Geological Survey
open-file report, 30 p.
Babenroth, D. L., and Strahl er, A. N., 1945, Geomorphology and
structure of the East Kaibab monocline, Arizona and Utah:
Geo-logical Society of America Bulletin, v. 56, no. 2,
p. 107-150.
Beus, S. S., Rush, R. W., and Smouse, Deforrest, 1966, Geological
investigations of experimental drainage basins 7-14, Beaver
Creek watershed, Coconino County, Arizona: Mimeograph
report, 47 p.
Cooley, M. E., 1960, Physiographic map of
Plateau-lower Little Colorado River area:
Geochronology ·Laboratories, p. 19-30.
the San Francisco
Arizona University,
1963, Hydrology of the Plateau uplands province, in Annual
-----r-eport on ground water in Arizona, spring 1962 to spring 1963,
by N. D. White, R. S. Stulik, E. K. Morse, and others:
Arizona State Land Department Water-Resources Report 15,
p. 27-38.
------
41
1976, Spring flow from pre-Pennsylvanian rocks in the south-western
part of the Navajo Indian Reservation, Arizona: U.S.
Geological Survey Professional Paper 521-F, 15 p.
Cooley, M. E., Akers, J. P., and Stevens, P. R., 1964, Selected lithe­logic
logs, drillers' logs, and stratigraphic sections, pt. 3 of
Geohydrologic data in the Navajo and Hopi Indian Reservations';
Arizona, New Mexico, and Utah: Arizona State Land
Department Water-Resources Report 12-C, 157 p.
Cooley, M. E., Harshbarger, J. W., Akers, J. P., and Hardt, W. F.,
1969, Regional hydrogeology of the Navajo and Hopi Indian
Reservations, Arizona, New Mexico, and Utah, with a section on
Vegetation by 0. N. Hicks: U.S. Geological Survey
Professional Paper 521-A, 61 p.
Cooley, M. E., and others, 1966, Maps showing locations of wells,
springs, and stratigraphic sections, pt. 4 of Geohydrologic data
in the Navajo and Hopi Indian Reservations, Arizona, New
Mexico, and Utah: Arizona State Land Department Water­Resources
Report 12-D, 2 sheets.
Cosner, 0. J., 1962, Ground water in the Wupatki and Sunset Crater
National Monuments, Coconino County, Arizona: U.S.
Geological Survey Water-Supply Paper 1475-J, p. 357-374.
Dalrymple, Tate, 1960, Flood-frequency analyses: U.S. Geological Survey
Water-Supply Paper 1543-A, 80 p.
Davis, G. E., Hardt, W. F., Thompson, L. K., and Cooley, M. E., 1963,
Records of ground-water supplies, pt. 1 of Geohydrologic data
in the Navajo and Hopi Indian Reservations, Arizona, New
Mexico, and Utah: Arizona Stat􀆦􊘠 Land Department Water­Resources
Report 12-A, 159 p.
Feth, J. H., 1953, A geologic and geophysical reconnaissance of the
Doney Park-Black Bill Park area, Arizona, with reference to
ground water, with a section on Geophysics by C. B. Yost,
Jr.: U.S. Geological-Survey Circular 233, 11 p.
Feth J. H., and Hem, J. D., 1963, Reconnaissance of headwater springs
in the Gila River drainage basin, Arizona: U.S. Geological
Survey Water-Supply Paper 1619-H, 54 p.
Gilman, C. R., 1965, Geology and geohydrology of the Sitgreaves
Mountain area, .Coconino County, Arizona: Tucson, University
of Arizona, unpublished master's thesis, 87 p.
Huddle, ·J. W., and Dobrovolny, Ernest, 1945, Late Paleozoic stratigraphy
and oil and gas ·possibilities of central and northeastern
Arizona; U.S. · Geological Survey Oil and Gas Investigations
Preliminary Chart 10 ..
42
Johnson, P. W., and Sanderson ,. R. B., 1968, Spring flow into the
Colorado River-Lees Ferry to Lake Mead, Arizona: Arizona
State Land Department Water-Resources Report 34, 26 p.
Kelley, V. C., 1955, Regional tectonics of the Colorado Plateau and
relationship to the origin and distribution of uranium:
University of New Mexico Publications in Geology, no. 5, 120 P
Kister, L. R:, and Hatchett, J. L., 1963, Selected chemical analyses of
the ground water, pt. 2 of Geohydrologic data in the Navajo
and Hopi I ndian Reservations, Arizona, New Mexico, and Utah:
Arizona State Land Department Water-Resources Report 12-B,
58 p.
Koons, E. D., 1948, Geology of the eastern Hualapai Reservation [Ariz.]:
Plateau, v. 20, no. 4, p. 53-60.
Levings, G. W., 1980, Water resources in the Sedona area, Yavapai and
Coconino Counties, Arizona: Arizona Water Commission
Bulletin 11, 37 p.
Levings, G. W., and Mann, L. J., 1980, Maps showing ground-water
conditions in the upper Verde River area, Yavapai and Coconino
Counties, Arizona-1978: U.S. Geological Survey Open-File
Report 80-726, 2 sheets.
Lohman, S. W., 1979, Ground-water hydraulics: U.S. Geological Survey
Professional Paper 708, 70 p.
Lohman, S. W., and others, 1972, Definitions of selected ground-water
terms-Revisions and conceptual refinemehts: U. S. Geological
Survey Water-Supply Paper 1988, 21 p.
Love, S. K., 1961, Quality of surface water of the United States, 1957,
Parts 9-14: U. S. Geological Survey Water-Supply Paper 1523,
497 p.
Mann, L. J., 1976, Ground-water resources and water use in southern
Navajo County, Arizona: Arizona Water Commission Bulletin 10,
106 p.
McGavock, E. H., 1968, Basic ground-water data for southern Coconino
County, Arizona: Arizona State Land Department Water-
Resources Report 33, 49 p.
McGavock, E. H., Edmonds, R. J., Gillespie, E. L., and Halpenny,
P. C., 1966, Supplementat records of ground-water supplies,
pt. 1-A of Geohydrologic data in the Navajo and Hopi Indian
Reservations, Arizona, New Mexico, and Utah: Arizona State
Land Department Water-Resources Report 12-E, 55 p.
43
McKee, E. D., 1934, The Coconino sandstone-its history and origin:
Carnegie Institute, Washington Publication 440, p. 77-115.
------
1938, The environment and history of the Toroweap and
Kaibab Formations of northern Arizona and southern Utah:
Carnegie Institute, Washington Publication 492, 268 p.
------
1975, The Supai Group-Subdivision and nomenclature: U.S.
Geological Survey Bulletin 1395-J, 11 p.
Metzger, D. G., 1961, Geology in relation to availability of water along
the south rim, Grand Canyon National Park, Arizona: U.S.
Geological Survey Water-Supply Paper 1475-C, 138 p.
Moore, D. 0., 1968, Estimating mean runoff in ungaged semiarid areas:
Nevada Water Resources Bulletin 36, 39 p.
Moore, R. T., Wilson, E. D., and O'Haire, R. T., 1960, Geologic map of
Coconino County, Arizona: Arizona Bureau of Mines map, scale
1:375,000.
Moosburner, Otto, 1970, A proposed streamflow-data program for Arizona:
U.S. Geological Survey open-file report, 56 p.
Patterson, J. L., and Somers, W. P., 1966, Magnitude and frequency of
floods in the United States-Part 9, Colorado River basin:
U.S. Geological Survey Water-Supply Paper 1683, 475 p.
Peirce, H. W., and Gerrard, T. A., 1966, Evaporite deposits of the
Permian Holbrook basin, Arizona, in Second symposium on salt,
J. L. Rau, ed.: Northern Ohio Geological Society, v. 1,
p. 1-10.
Robinson, H. H., 1913, The San Francisco volcanic field, Arizona: U.S.
Geological Survey Professional Paper 76, 213 p.
Roeske, R. H., 1978, Methods for estimating the magnitude and frequency
of floods in Arizona: Arizona Department of Transportation
ADOT-RS-15(121), 82 p.
Rush, R. W., 1965, Report of geological investigations of six experimental
drainage basins, Beaver Creek watershed, Yavapai County,
Arizona: Mimeograph report, 27 p.
Searcy, J. K., 1959, Flow-duration curves: U.S. Geological Survey
Water-Supply Paper 1542-A, 33 p.
Sellers, W. D., and Hill, R. H., eds., 1974, Arizona climate, 1931-1972:
Tucson, University of Arizona Press, 616 p.
44
Shoemaker, E. M., Squires, R. L., and Abrams, M. J., 1974, The Bright
Angel and Mesa Butte fault systems of northern Arizona, in
Geology of northern Arizona with notes on archaeology and
paleoclimate-Part I, Regional studies: Geological Society of
America, p. 355-391.
Thomsen, B. W., 1969, Surface-water supply for the city of Williams,
Coconino County, Arizona: U.S. Geological Survey open-file
report, 50 p.
Twenter, F. R., 1962, Geology and promising areas for ground-water
development in the Hualapai Indian Reservation, Arizona: U.S.
Geological Survey Water-Supply Paper 1576-A, 38 p.
Twenter, F. R., and Metzger, D. G., 1963, Geology and ground water in
Verde Valley-the Mogollon Rim region, Arizona: U.S.
Geological Survey Bulletin 1177, 132 p.
University of Arizona, 1965a, Normal annual
May-September precipitation-1931-1960,
University of Arizona map.
precipitation-normal
State of Arizona:
1965b, Normal annual precipitation-normal October-April
University of ------ precipitation-1931-1960, State of Arizona:
Arizona map.
U.S. Geological Survey, 1919-60, Colorado River basin, pt. 9 of Surface
water supply of the United States: U.S. Geological Survey
water-supply papers (issued annually).
1961-75, Water resources data of Arizona, Water years
------ 1961-74, Part 1, Surface Water Records: U.S. Geological
Survey water-data reports (published annually).
U.S. Public Health Service, 1962, Drinking water standards, 1962: U.S.
Public Health Service Publication 956, 61 p.
U.S. Weather Bureau, 1967, Arizona, 10-year 24-hour precipitation:
U.S. Department of Commerce map.
Location
T. 18 N., R. 17 E.,
SE\S\.% sec. 27
Do.
T. 15 N., R. 13 E.,
S\-%SE􀇌􌰠 sec. 19
Do.
Do.
T. 18 N., R. 15 E. ,
Nh%NW% sec. 31
T. 21N., R. 7E.,
SEJ.iS\f.>.f sec. 4
T. 21 N., R. 7 E. ,
N\<.%NE\ sec. 9
Sampling
site
Chevelon Creek
Near gaging
station 09398000;
base flow
Near gaging
station 09398000;
storm runoff
Clear Creek
Near gaging
station 09398500;
snowmelt runoff
Near gaging
station 09398500;
storm runoff
Near gaging
station 09398500;
snowmelt runoff
Jacks Can􀁚􅩯on
Near gag'ing
station 09399400;
storm runoff
Schultz Can􀁚􅩯on
At partial-record
station 09400595;
storm runoff
Rio de Flag
At partial-record
station 09400600;
storm runoff
Date of Discharge Tern-collec-
(cubic pera-tion
feet per ture
second) ( ° C)
5-25-54 4.0 21
7-12-55 3.4 24
5-12-71 4.2 17
10- 4-71 123 13
3-11-66 500 2
10-13-71 0.38 14
10-17-72 4.9 16.5
3-20-73 258
4-25-73 1,910
8-21-71 4.0 23
12-28-71 127 3. 5
12-30-71 23 2.0
12-31-71 10 .5
3-13-73 15 7.0
3-13-73 94 6.5
Table 4.--Chemical analyses of water from selected streamflow sites
[Analyses in milligrams per liter, except as indicated. T, trace.
Dissolved solids: Sum of determined constituents]
Magne- Potas- Bicar-
Car-
Silica Calcium sium Sodium sium bonate
bon- Sulfate
(Si02) (Ca) (Mg) (Na) (K) (HC03 ) ate (504 )
(C03 )
LITTLE COLORAOO RIVER DRAINAGE BASIN
9. 6 69 39 591 228 0 139
9.4 70 43 587 249 0 139
6.8 68 45 640 5.9 263 0 170
3. 7 18 5.2 15 1.1 75 0 12
7.2 3.9 2.1 34 0 8.0
3. 7 25 12 1. 6 .5 128 0 6.5
4.6 20 9.8 2.8 1.0 102 0 7.0
4.0 9. 0 4.2 1. 0 0.5 45 0 6. 7
4. 7 9.2 4.1 1. 0 0.6 45 0 5.4
9.1 25 2.2 2.2 4. 7 97 0 3.3
14 13 2.5 2.6 2.4 46 0 5.8
14 11 2.6 1.0 2. 7 46 0 5.5
15 13 3.0 2. 0 2. 7 47 0 5.9
26 11 4.2 4.3 2. 7 52 0 8.2
23 10 4.3 3.8 2.6 53 6.1
Hardness Specific
Chlo- Fluo-as
CaC03 conduct-ride
ride
Dis- ance Ph
(Cl) CF)
solved Calcium, Non- (micro-solids
magne- carbon- mhos at
sium ate 25°C)
910 0.4 1,870 332 146 3,440
905 .3 1,880 352 148 3,380 7.2
960 .2 2,030 350 140 3,590 7.6
22 .1 114 66 207 7.2
LO .1 39 34 6 68 7.1
1. 7 . 0 114 110 7 2Dl 8.1
4.1 .1 100 90 7 180 7.5
1.5 .1 49 40 3 84 7. 7
1.6 . 0 49 40 3 85 7. 6
1.4 .4 98 71 D 157 7.4
3. 7 .2 67 43 5 85 6.8
2.8 .2 63 38 0 86 6.9
1.9 .1 68 45 6 89 7.0
1.6 .2 107 45 2 109 7.2
2.0 .2 104 43 108 7.2
Table 4.--Chemical analyses of water from selected streamflow sites--Continued
Date of Di scharge Tem- Magne- Potas- Bicar- Car-
Location Sampling call ec- (cubic pera- Silica Calcium sium Sodium Slum bonate bon- Sul fate
site ticn feet per ture (Si0
2
) (Ca) (Mg) (Na) (K) (HCOS) ate (SO.)
second) (OC) (COs)
LITTLE COLORADO RIVER DRAINAGE BASIN-{;ONTINUEO
Switzer Canyon
T. 21 N., R. 7 E., At partial-record 3-13-73 75 4.5 11 4.9 1.9 1.6 1.4 29 2.3
SW'-:iSE~ sec. 10 stat i on 09400680;
storm runoff
Little Colorado
Rlver
T. 29 N., R. 8 E., At gaging station 10-28-69 75 11.0 34 4.6 170 4.3 232 202
NW'-:i sec. 5 09402000; storm 3-26-70 56 4.5 17 2.8 96 2.6 155 37
runoff 1-27-71 0.60 0.5 8.0 91 24 160 5.2 205 420
10-28-71 2,300 9.0 7.7 11 2.4 89 1.9 118 63
1-27-72 31 1.0 9.8 76 18 200 3.9 209 180
T. 33 N., R. 6 E., 3.1 mi 1 es above 5-17-66 22 17 112 77 761 464 170
NW' .. SW' .. sec. 33 mouth of river; 7-12-66 230 24 15 120 79 765 494 170
base flow 11- 2-66 217 18 96 76 795 476 175
3-15-67 18 18 120 69 777 488 175
HAVASU CREEK DRAINAGE BASIN
West Cataract
Creek
T. 22 N., R. 2 E., At partial-record 3-26-73 3.3 0.5 19 11 4.0 2.9 2.2 56 5.4
NW'-:i sec. 31 stat i on 09403930;
storm runoff
Cataract Creek
T. 27 N., R. 2 W. , At partial-record 4- 6-73 17 13.0 15 16 3.3 3.6 2.5 75 4.6
NE~SE~ sec. 13 station 09404100;
storm runoff
Havasu Creek
T. 33 N., R. 4 W., 2 miles below 8-23-68 53.7 23 78 44 41 436 36
sec. 10 Supai Village;
base flow
T. 34 N., R. 4 W. , 4 miles below 6-16-51 21 52 47 28 338 trace 38
sec. 32 Supai Village;
base flow
T. 34 N., R. 4 W., 500 feet above 6-16-51 63.3 21 304 trace
sec. 31 mouth; base
flow
Chlo- Fluo-ride
ride Dis-
(Cl) (F) so lved
solids
0.5 0.1 51
72 628
78 355
38 0.6 916
65 0.5 326
250 0.4 868
1,200 0.2 2,560
1,210 0.2 2,600
1,210 0.3 2,600
1,200 0.3 2,600
2.2 0.1 106
1.7 0.0 109
48 0.3 485
48 380
48
Hardness
as CaC03
Calcium, Non-magne-
carbon-sium
ate
20
104 0
54 0
330 162
37 0
260 92
595 215
625 220
550 160
585 185
44
54
374 16
323 46
Specific
conduct-ance
(micro-mhos
at
25°C)
50
990
570
1,270
497
1,500
4,540
4,580
4,580
4,610
103
109
836
704
661
Ph
.j::..
00
7.0
7.8
8.2
8.0
7.8
7.3
7.8
7.7
7.4
7.3
7.3
7.8
Table 4.--Chemical analyses of water from selected streamflow sites-Continued
Date of Discharge Tem- Magne- Potas- Bicar- Car-location
Sampling collec- (cubic pera- Silica Calcium sium Sodium sium bonate bon- Sulfate
site tion feet per ture (Si0
2
) (Ca) (Mg) (Na) (K) (HCO') ate (SO.)
second) (OC) (CO.)
VERDE RIVER DRAINAGE BASIN
Oak Creek
T. 16 N., R. 4 E., At gaging station 9-14-67 24.7 22 18 47 20 1.6 224 4.0
NEliNW\[SEli sec. 23 09504500; base
flow
Do. At gagi ng stati on 4-15-68 63 16 15 24 11 4.1 126 5.0
09504500; snowmelt
runoff
Do. At gagi ng stati on 10-12-71 25 22 15 42 20 8.6 1.0 242 4.8
09504500; base
runoff
Do. At gaging station 4-10-73 764 10 12 14 5.2 2.2 0.8 64 3.6
09504500; snowmelt
ru_noff
Wet Beaver Creek
T. 15 N., R. 6 E., At gaging station 9-15-67 6.2 22 21 29 14 5.0 164 2.0
NWlJ:SW1:t sec. 24 09505200; base
runoff
T. 15 N., R. 6 E., Near gaging 10-14-71 6.9 17.5 20 24 14 6.3 1.1 164 3.8
N~SW%: sec. 24 station 09505200;
base runoff
Do. Near gage, snowmelt 4- 3-73 110 14 11 4.7 2.2 1.3 56 7.8
runoff
T. 15 N., R. 6 E., 2.5 miles below 4-1S-68 32 14 17 11 6.4 3.2 68 4.0
NEliNEl; sec. 28 gaging station
09505200; snowmelt
runoff
Red Tank Draw
T. 15 N., R. 6 E., At gaging station 4-15-68 0.3 17 25 38 17 6.9 200 5.0
S8:iNE!.i sec. 16 09505250; s nOWllle 1 t 4- 3-73 52 8 14 12 4.4 2.2 1.5 57 7.0
runoff
Chlo- Fluo-ride
ride Dis-
(Cl) (F) solved
solids
10 211
3.5 0.1 125
8.9 220
1.3 0.1 71
4.S lS6
2.8 0.1 153
2.1 0.0 71
1.5 0.1 76
7.0 0.1 197
2.4 0.0 72
Hardness
as CaeOa
Calcium, Non-magne-
carbon-sium
ate
198 64
104
190
56 4
132
120
47
54
164 0
48 1
Specific
conduct-ance
(micro-mhos
at
2S0C)
396
210
380
112
267
249
99
118
330
105
Ph
7.5
7.1
8.1
7.5
7.3
8.1
7.7
6.7
7.4
7.8
.t>.
<D
Table 4.--Chemical analyses of water from selected streamflow sites-Continued
Date of Di scharge Tem-
Magne- Potas- Bicar- Car-
Location Sampling collec- (cubic pera- Silica Calcium sium Sodium sium bonate bon- Sulfate
site ticn feet per ture (Si0
2
) (Ca) (Mg) (Na) (K) (HCO') ate (SO.)
second) (OC) (CO.)
VERDE RIVER DRAINAGE BASIN-CONTINUED
Rattlesnake Can:ton
T.16N.,R.7E., 2 mil es above 4-15-68 6.9 14 17 6.0 3.6 4.4 30 11
SE~SE~ sec. 18 gaging station
09505300;
snowme 1 t runoff
T. 16 N., R. 6 E., Near gage 4-16-73 78 13 5.8 2.8 1.8 0.5 29 3.6
N~SW% sec. 24 09505300;
snowmelt
runoff
Dr:l Beaver Creek
T. 15 N., R. 5 E., At gaging station 4-15-68 58 15 16 7.6 3.6 2.1 40 4.0
NE%NW'~ sec. 1 09505350; snoWine 1 t 3- 2-73 139 7.5 13 7.1 3.1 1.9 0.7 39 6.1
runoff 4-26-73 548 11 4.8 2.2 1.3 0.5 26 3.7
West C1 ear Creek
T. 13 N., R. 6 E., At gaging station 9-15-67 14.3 22 IS 42 20 8.7 236 5.0
NW%tMiNW% sec. 11 09505800; base 10-12-71 15 17 39 23 5.7 1.1 251 1.5
flow
Do. At gaging station 10-7-72 1,040 17 14 14 5.6 1.5 1.9 63 9.3
09505800; storm
runoff
Do. At gaging station 4-11-73 1,300 5.5 10 9.3 3.8 1.5 0.8 45 4.0
09505800; snowmelt
runoff
T. 13 N., R. 5 E., 5 miles below 4-15-68 135 15 18 17 8.1 3.4 96 3.0
SWl.!NE~ sec. 13 gaging station
09505800;
snowmelt runoff
Chlo- Fluo-ride
ride Dis-
(Cl) (F) solved
solids
2.5 0.1 60
0.1 0.0 43
1.0 0.1 54
1.8 0.1 53
1.5 0.0 38
4.5 0 214
3.3 0.1 214
1.9 0.1 80
0.9 0.1 53
1.5 0.1 98
Hardness
as CaCO.
Calcium~ Non-magne-
carbon-sium
ate
30
26
34
31
21
186
190
58
39
76
Specific
conduct-ance
(micro-mhos
at
25°C)
79
58
77
71
50
366
370
127
81
161
Ph
U1 o
6.4
7.6
7.0
7.8
7.7
7.5
6.8
7.3
7.0
Location
(A-17-17)22ccc
(A-18-16)30dd
(A-18-16)31bbb
(A-32-6)3bd(a)
(A-32-6)36ada
(A-32-6)36add
(A-32-7)31bbc
(A-33-6)33b
(A-31-2)7
(A-31-2)l3abb
(B-27-9)20acb
(B-33-8)36d
Date of
collec­tion
7- 8-66
7- 7-66
7- 7-66
1-29-66
7-12-66
6-14-50
5-17-66
7-12-66
5-17-66
7-12-66
10-16-57
4-9-58
5-15-58
6-20-60
Dis­charge
(gallons
per
minute)
15,750
42,750
42,250
11,250
210
300R
>300
2,700E
Tem­pera­ture
(OC)
19
17
20
23
21
22
24
12
22
26
Table 5.--Chemical analyses of water from selected springs
[Analyses in milligrams 'per llter~ except as wdicated. Discharge: R. reported; E. estimated. Dissolved solids: Sum of
determined constituents. Remarks: Stratigraphie names indicate water-bearing unit]
Silica
(Si02 )
14
13
14
17
19
17
16
17
15
9.2
12
26
Calcium
(Ca)
114
50
46
646
214
264
252
238
112
120
52
54
50
54
Magne­sium
(Mg)
38
24
27
291
73
79
76
67
77
79
31
35
21
80
Sodium
(Na)
513
152
178
576
8,184
623
535
785
761
765
27
11
18
58
Potas­sium
(K)
Bicar­bonate­(
HCO,)
Car-bon-
Sulfate
ate (504 )
(CO,)
Chlo­ride
(Cl)
LITTLE COLORADO RIVER DRAINAGE BASIN
23
166
222
160
2,470
936
964
951
840
464
494
300
32
50
2,950
135
147
140
175
170
170
230
280
920
11,000
910
815
835
1,210
1,200
1,210
COLORADO RIVER DRAINAGE BASIN
267 33 44
308 28 14
228 15 24
532 38 80
Fluo­ride
(F)
0.1
.1
.2
1.5
.2
.3
.2
.2
.2
.2
.2
.5
Dis­solved
solids
930
686
1,710
24,380
2,430
2,340
2,320
2,900
2,560
2,600
328
305
282
572
Hardness
as CaeOa
Calcium.
magne­sium
442
224
228
2,810
835
984
940
870
595
625
257
278
212
462
Non­carbon­ate
306
42
97
787
68
194
161
182
215
38
26
26
Specific
conduct­ance
(m; cro­mhos
at
25°C)
1,530
1,280
3,200
33,800
4,170
3,940
3,960
5,000
4,540
4,580
584
543
460
1,100
Ph
7.4
7.7
7.8
6.5
7.0
6.5
6.8
6.9
7.3
7.8
Remarks
Seep zone in Cheve 1 on
Creek; Coconino
Sandstone
Seep zone in Clear Creek;
Coconi no Sandstone.
Do.
Si-Pa-Po Spring; Little
Colorado River mile
4.5; Tapeats Sandstone.
First spring below Blue
Spring; Little Colorado
River mile 12.9; Muav
Limestone.
Blue Spring; Little
Colorado River mile
13.1; Muav Limestone.
Do.
Second spring below Blue
Spring; Little Colorado
River mile 12.8; Muav
Limestone.
Composite of all spring
flow from Blue Spring
to Little Colorado
River mile 3.1; Muav
Limestone and
Tapeats(?) Sandstone.
Do.
Hermit Springs; Muav
Limestone.
Indian Gardens Spring;
Muav Limestone.
Oi amond Spri ng; Muav
Limestone.
Warm Spri ng; Muav
Limestone.
(}1
~
Location
(B-33-4)26b
(A-12-7)14da
(A-14-8) 32aa
(A-14-9)31dd
(A-15-7)14acc
(A-16-4 )23bbd
(A-16-4 )23dda
(A-17-3)5db
(A-19-6)l5ddd
Date of
collec­tion
10-20-50
8- 7-65
12-28-66
11-12-67
6-29-68
2-16-52
5-28-59
5-27-59
10-19-59
7-14-59
5-20-68
8- 4-49
5-20-68
10-10-51
8-10-46
Dis­charge
(gallons
per
minute)
27,900
26,700
29,900
27,700
18,600
l,ODOE
100E
l,350E
3,900
2,075
2,700
290
Tem­pera­ture
(OC)
21
21
21
20
21
16
11
16
20
19.5
20
20
19
11
Silica
(si02 )
18
18
20
14
20
21
23
20
21
18
19
15
Calcium
(Ca)
133
74
118
125
134
104
51
55
29
56
54
42
42
72
32
Magne­sium
(Mg)
48
45
45
32
43
40
22
22
10
22
25
19
18
27
13
Table 5.--Chemical analyses of water from selected springs--Continued
Sodium
(Na)
16
27
36
33
40
42
Potas­sium
(K)
6.9
5.5
5.1
4.8
13
1.0
8.7
10
5.8
9.2
Bicar­bonate­(
HC03 )
Car-bon-
Su If ate
ate (SO.)
(C03)
HAVASU CREEK DRAINAGE BASIN
588
416
542
523
602
36
36
38
40
38
VERDE RIVER DRAINAGE BASIN
485
268
284
147
270
279
227
229
341
163
o
6.9
27
1.6
.6
.2
4.7
5.0
3.7
3.0
7.6
2.9
Chlo­ride
(Cl)
48
48
46
45
50
6.0
4.0
2.5
·20
22
8.0
8.5
10
3.0
Fluo­ride
(F)
0.2
.2
.3
.2
.3
.1
.1
.2
.2
.2
.2
.2
.4
Dis­solved
solids
584
565
558
623
440
239
248
143
270
281
212
214
307
135
Hardness
as CaCOa
Calcium,
magne­sium
530
368
478
446
512
424
218
228
115
228
238
183
180
290
134
Non­carbon­ate
48
27
34
18
18
10
Specific
conduct­ance
(micro­mhos
at
25°C)
1,030
820
973
961
1,050
753
401
418
236
463
498
364
374
543
270
Ph
7.7
7.7
7.4
7.2
8.0
7.8
7.4
7.6
7.3
7.1
Remarks
01
N
Havasu Spri ngs;
Pennsylvanian Limestone.
Do.
Do.
Do.
Do.
Fossi 1 Spri ngs; Naco
Formation.
Buckhorn Spri ng;
Coconi no Sandstone.
Bear Spring; Coconino
Sandstone.
Wet Beaver Creek Spri ngs;
Coconino Sandstone.
Bubbling Pond; supai(?)
Formation.
Do.
Page Springs; supai(?)
Formation.
Do.
SUmmers Spring; Redwall
Limestone.
Sterling Spring; Coconino
Sandstone.
Well
location
(A-18-14) 13abd2
13baa
13bad
13cab
13dbb
36daa
(A-19-13)7bbb
(A-19-14)21a
(A-20-6)2bca
(A-20-12l:;)14dda
24cbb
(A-20-13)35da
(A-23-10)lbb
13dc
(A-25-2)27aba
(A-27-9)6dc1
Date of
collect­ticn
8-25-53
11-17-59
10-25-65
3- 3-66
1- 8-55
11-17-59
11-17-64
10-25-65
1-10-63
10-16-64
10-26-65
1-8-55
3-3-66
4-27-55
10-25-65
8- 2-50
5- 3-66
11-20-33
6- -66
11-11-33
5-11-66
3-29-68
11-20-33
3-12-53
7- 8-46
5- -66
11-20-33
3-12-53
5-12-66
10-19-54
7-19-65
10-19-54
7-18-65
1-10-70
5-15-56
5-12-66
Tem­per­a­ture
(OC)
17
17
16
23
17
Silica'
(5i02 )
19
11
7
6.8
10
12
8
10
10
8.2
5.2
14
15
22
7.6
13
12
13
8.5
12
9.4
11
Table 6. --Chemical analyses of water from selected wells
[Analyses by U.S. Geological Survey, except as indicated. Analyses in milligrams per liter, except as indicated.
Dissolved solids: Sum of determined constituents. Remarks: CT, sample obtained from closed storage tank
at well; ATl, analysis by Arizona Testing laboratories; stratigraphic names indicate water-bearing unit]
Iron
(Fe)
in solu­tion
at
time of
analysis
0.01
0.07
0.01
. 07
Cal­cium
(Ca)
60
90
98
82
70
70
38
92
113
116
76
64
66
65
74
72
94
91
79
73
21
108
98
105
106
78
78
76
57
73
93
89
Magne­sium
(Mg)
34
39
44
37
43
44
10
12
8
12
32
36
35
37
44
40
47
47
11
50
47
45
44
43
40
40
47
57
59
65
9.6 351
101
95
58
62
50di - Potas-urn
sium
(Na) (K)
79
254
389
249
93
133
178
294
64
152
288
14
7.1
13
133
55
16
18
239
260
7.4
25
20
31
30
33
33
36
159
147
370
359
4,330
27
39
Bicar­bon­ate
(HC03 )
264
256
251
258
276
276
150
288
249
300
300
251
257
246
288
259
255
224
230
264
265
132
226
207
225
224
232
233
236
205
200
172
1,110
536
527
Car­bonate
(C03 )
o
o
o
o
8
o
o
o
132
5u1- Chlo-fate
ride
(504 ) (Cl)
110
110
325
130
100
90
123
230
111
100
250
90
99
110
215
122
226
205
135
135
92
432
390
410
246
226
280
308
106
214
254
16
11
12
36
90
82
21
21
392
413
Fluo­ride
(F)
0.4
.4
.2
.5
.2
.3
.4
.3
.2
1.2
.2
o
.2
.1
o
.2
o
.1
2.0 3.0 .1
295
269
280
281
157
143
147
213
230
270
255
270
32
43
26
22
26
24
63
64
62
205
236
605
615
6,720
53
70
o
.3
o
.2
o
.2
.1
.8
.5
.6
.6
.5
.4
.4
Ni­trate
(NO)
3
1.0
.4
1.2
.2
1.7
.2
.4
.3
3.2
.6
Oi5-
so lved
solids
531
1,06.0
1,340
1,040
692
710
758
1,090
541
750
1,040
351
348
366
620
494
512
502
1,020
1,070
132
616
566
600
608
488
486
490
792
1,500
Hardness
as CaC03
Calcium, Non-magne-
car-sium
bonate
289
386
360
384
326
354
274
370
330
322
340
290
314
306
320
308
332
415
392
390
374
98
475
438
447
446
371
359
356
336
416
474
490
138
123
204
157
268
262
263
168
163
168
252
334
353
12,400 1,470 339
547 490 51
492 60
Specific
conduct­ance
(micro­mhos
at
25°C)
1,850
1,370
587
887
844
778
1,890
220
859
891
890
808
799
1,330
1,440
2,590
2,610
20,200
980
1,000
pH
7.5
7.2
7.5
7.5
7.7
7.3
8.6
7.5
7.6
7.6
7.6
7.9
7.6
7.8
7.6
7.7
7.5
7.3
7.1
7.5
7.6
8.0
7.6
8.4
7.5
7.6
Remarks
Winslow 1; ATl; Coconino
Sandstone.
Do.
Do.
Coconino Sandstone.
Winslow 2; ATL; Coconino
Sandstone.
Do.
Coconino Sandstone.
ATl; Coconino Sandstone.
Winslow 5; ATL; Coconino
Sandstone and Supai
Formation.
Do.
Do.
Winslow 3; ATL; Coconino
Sandstone.
Coconino Sandstone.
Winslow 4; ATL; Coconino
Sandstone and Supai
Formation.
Do.
Coconino Sandstone.
Do.
Do.
Do.
Do.
Do.
City of Flagstaff, Woody
Mountai n 6; Coconi no
Sandstone and Supai
Formation.
Coconino Sandstone
Do.
CT; Coconino Sandstone.
Do.
Coconino Sandstone.
Do.
00 .
Coconi no(?) Sandstone.
Do.
Do.
Do.
Tapeats Sandstone.
CT; Supai Formation.
Supai Formation.
U1
VJ