U.S. Department of the Interior

U.S. Geological Survey

Fact Sheet 2006–3008 

March 2006 Printed on recycled paper

The Detrital, Hualapai, and 

Sacramento Valleys are broad, 

intermountain desert basins in Mohave 

County, northwestern Arizona, and are 

home to residents in the city of Kingman 

and several rural communities (fig. 1). 

Ground water is the primary source of 

water in these valleys and is essential for 

many economic and cultural activities. 

As in many parts of the Western United 

States, population growth in these 

valleys is substantial. From 2000 to 

2004, the population of Kingman grew 

from 20,100 to 24,600—an increase 

of 22 percent (Arizona Department 

of Economic Security, 2005). During 

the same time period, the population 

of Mohave County increased by 16 

percent. Management of the available 

ground-water resources in these valleys 

guided by a comprehensive scientific 

understanding can help the growing 

communities to meet their needs in a 

sustainable manner. 

In 2005, the U.S. Geological Survey 

(USGS) began an investigation of the 

hydrogeology of the Detrital, Hualapai, 

and Sacramento Valleys in cooperation 

with the Arizona Department of Water 

Resources (ADWR) as part of the Rural 

Watershed Initiative (RWI), a program 

established by the State of Arizona 

and managed by the ADWR. Other 

projects in the RWI program include 

investigations that began in 2005 in the 

middle San Pedro Basin and the Willcox 

and Douglas Basins, and investigations 

that began in 1999 in the Coconino 

Plateau, the Mogollon Highlands, and 

upper and middle Verde River study 

areas (http://az.water.usgs.gov/rwi-ii/). 

Figure 1.  Physiography and location of water-level and well-log data for Detrital, Hualapai, and

Sacramento Valleys, northwestern Arizona.

Kingman

HUALAPAI PEAK Bullhead City

Was pa a al u H i h

W

Tru ton x

ash

W

Sacramento ash

tri l

Lake Mohave

Co

do

River lo ar

Hoover

Dam

ARIZ

O

N

A

NEVA

D

A

Sacramento

Valley

Red

Lake

36o

30’

34o30’

Lake Mead

BLACK MOUNTAINS

Detrital

Valley

GRAND

WASH

CLIFFS

D ta e

HILLS

WHITE

MOUNTAINS

MOHAVE

Wash

0 10 MILES

0 10 KILOMETERS

Base from U.S. Geological Survey

digital data, 1:100,000, 1982

Universal Transverse Mercator

projection, Zone 12

95

68

67

40

40

35o

114o

114o30’

93

Hualapai

Valley

Phoenix

ARIZONA

Detrital

Valley

Sacramento

Valley

Hualapai Valley

A

RIZONA

C

A

LIFORNIA

EXPLANATION

VALLEY DIVIDE

WELLS FOR WHICH LOGS

 ARE AVAILABLE:

 Less than 10 water levels

 are available

 10 or more water levels

 are available

WELLS FOR WHICH LOGS

 ARE UNAVAILABLE:

 Less than 10 water levels

 are available

 10 or more water levels

 are available

River

Co

do

lo

ar

CERBAT MOUNTAINS

HUALAPAI MOUNTAINS BLACK MOUNTAINS

GARNET MOUNTAIN

Prepared in cooperation with the

ARIZONA DEPARTMENT OF WATER RESOURCES

Hydrogeologic Investigation of the Detrital, Hualapai, and 

Sacramento Valleys of Northwestern Arizona: 

A Project of the Rural Watershed Initiative
The primary objective of this 

investigation is to improve the 

understanding of the hydrogeologic 

systems of Detrital, Hualapai, and 

Sacramento Valleys. This will be 

accomplished by:

1. Assessing the current knowledge of the 

ground-water flow system and existing 

data-collection networks, and identifying 

additional data needs.

2. Improving the understanding of the 

extent and lithology of geologic units 

and structures, and their relation to the 

storage and movement of ground water.

3. Improving the understanding of 

ground-water movement and the 

estimates for ground-water budget terms, 

including recharge, discharge, and total 

water in storage.

4. Evaluating the ground-water quality 

for key water uses.

5. Establishing a hydrologic-monitoring 

network to detect and characterize 

changes in aquifer conditions.

6. Informing the hydrologic community 

and valley residents about hydrologic 

conditions.

Physical Setting

The Detrital, Hualapai, and 

Sacramento Valleys are three distinct 

northwest-southeast trending alluvial 

basins in the Basin and Range 

Physiographic Province. The valley 

floors of Detrital and Hualapai Valleys 

generally slope downward to the north, 

and the valley floor of Sacramento 

Valley generally slopes downward to the 

south. Valley floor elevations range from 

about 3,500 ft near Kingman to about 

500 ft at the mouth of Sacramento Wash. 

Mountain crests rise as much as 5,500 

ft above valley floors, and the highest 

mountain in the study area is Hualapai 

Peak at 8,417 ft. 

The climate of the valleys is arid to 

semiarid with hot summers and mild 

winters. Maximum daily temperatures 

in the valley floors typically are between 

90 and 110oF during the summer, and 

between 50 and 70oF during the winter 

(Western Regional Climate Center, 2005). 

Annual precipitation on the valley floors 

ranges from about 5 to 10 in. Valley 

floors generally are covered with sparse 

desert vegetation (fig. 2) owing to the 

hot temperatures and little precipitation. 

Shrubs and trees cover mountain slopes 

and peaks in the higher elevations where 

temperatures are cooler and precipitation 

is greater. Annual precipitation in the 

mountains ranges from about 10 to 15 in. 

Geology

The structural basins of Detrital, 

Hualapai, and Sacramento Valleys were 

formed during the Basin and Range 

disturbance, in which mountain ranges 

and basins were formed on adjacent 

sides of high-angle normal faults 

(fig. 3). The bedrock of the mountains 

that separate the valleys consists of 

granitic, metamorphic, sedimentary, and 

volcanic rocks (fig. 4). In most areas, 

the bedrock is relatively impermeable 

compared to the basin fill and forms 

barriers to ground-water movement in the 

basin-fill aquifer. The Grand Wash Cliffs 

along the eastern margin of the Hualapai 

Valley consist of Paleozoic sedimentary 

rocks that extend eastward and mark the 

boundary between the Colorado Plateau 

and Basin and Range Physiographic 

Provinces (Gillespie and Bentley, 1971). 

The structural basins of the Detrital, 

Hualapai, and Sacramento Valleys 

contain basin fill (fig. 3) that ranges 

in thickness from a veneer along the 

mountain fronts to more than 5,000 ft 

in parts of each valley (Freethey and 

others, 1986; fig. 4). The basin fill is 

divided into older, intermediate, and 

younger hydrogeologic units (Gillespie 

and Bentley, 1971). Older basin fill is 

stratigraphically the oldest and deepest 

deposit, and consists of moderately 

consolidated fragments of rocks eroded 

from the surrounding mountains in a 

Figure 2.  Desert vegetation and municipal development of the city of Kingman in Hualapai Valley.

Mudstone and

evaporite deposits

VERTICAL SCALE GREATLY EXAGGERATED

FAULT—Arrows indicate

 direction of movement

BASIN FILL, 10 TO 25 MILES

Pre-Basin and Range sediments

Intermediate

basin fill

Change in pattern implies gradation in

unconsolidated material from coarse

grained to fine grained toward

the basin center

6,000 FEET

Older basin fill

Younger

basin fill

Bedrock of the 

mountains

Figure 3.  Generalized hydrogeologic section of the Detrital, Hualapai, and Sacramento Valleys

(modified from Anderson and others, 1992).
Figure 4.  Bedrock geology and basin-fill characteristics in the Detrital, Hualapai, and Sacramento

Valleys (modified from Richard and others, 2000, and Freethey and others, 1986).

silty-clay or sandy matrix. The grain size 

decreases from pebble- and boulder-size 

fragments in the fanglomerate near the 

mountains to coarse sand and interbedded 

clay and silt in the basin center. Each 

valley has large areas of older basin 

fill where more than 55 percent of the 

sediments are fine grained (Freethey 

and others, 1986; fig. 4). In the northern 

parts of Hualapai and Detrital Valleys, 

massive evaporite deposits occur in the 

older basin fill (Gillespie and Bentley, 

1971; Laney, 1979; Freethey and others, 

1986; fig. 4). The composition of the 

intermediate basin fill is similar to that of 

the older basin fill, and the intermediate 

basin fill also becomes finer grained 

towards the basin center; however, the 

thickness of the intermediate basin fill is 

on the order of a few hundred feet rather 

than a few thousand feet. Thickness of 

the younger basin fill, which consists of 

Holocene piedmont, stream, and playa 

deposits, is also less than that of the older 

basin fill. In the northern parts of Detrital 

and Hualapai Valleys, the basin fill also 

includes clastic sediments, limestone, 

and basalt flows of the Muddy Creek and 

Chemehueve Formations (Laney, 1979).

Hydrology and Water Use

Detrital, Hualapai, and Sacramento 

Valleys are drained by a network 

of streams that are intermittent or 

ephemeral owing to the dry climate. 

Detrital Wash, Hualapai Wash, and 

Sacramento Wash are the primary 

streams in their valleys and drain to the 

Colorado River. A topographic divide 

separates the northern and southern 

parts of Hualapai Valley. Truxton Wash, 

the only major stream that originates 

outside of the three valleys, drains part 

of the basin east of Hualapai Valley 

and flows westward into the southern 

part of the Hualapai Valley into Red 

Lake Playa (fig. 1). Streams generally 

flow only in response to regionally 

extensive winter storms or from spatially 

scattered summer thunderstorms. Runoff 

in mountain tributaries usually does 

not reach the valley’s primary stream, 

but rather infiltrates the streambed 

sediments or evaporates. Many stream 

channels become poorly defined with 

distance from the mountain front owing 

to the lack of streamflow. Although the 

Colorado River forms a small part of the 

perimeter of each valley, it generally is 

not a significant water supply within the 

valleys. 

Ground water from the basin-fill 

aquifer is the primary water supply for 

each of the three valleys. The older basin 

fill is the primary water-bearing deposit 

because intermediate and younger basin 

fill are above the water table in most 

areas. Most ground-water withdrawals 

in the valleys are for municipal and 

industrial uses; a small percentage of 

withdrawals is used for agriculture. 

The combined annual ground-water 

pumpage for the three valleys was 

about 6,600 acre-ft in 1991; by 2000, 

pumpage had nearly doubled to about 

11,000 acre-ft (Tadayon, 2005). The 

combined annual recharge for the three 

valleys was estimated to be about 9,000 

acre-ft (Freethey and Anderson, 1986), 

and ground-water storage was estimated 

to be about 13 million acre-ft (Arizona 

Department of Water Resources, 1994). 

Regional ground-water movement in 

the basin-fill aquifer generally is from 

the mountain fronts towards the valley 

center and then along the valley axis to 

the Colorado River. In general, depths 

E

5

1

5

5

1

Kingman

Bullhead City

Lake Mohave

Co

do

River lo ar

Hoover

Dam

ARIZ

O

N

A

NEVA

D

A

Sacramento

Valley

36o

30’

34o30’

Lake Mead

Detrital

Valley

0 10 MILES

0 10 KILOMETERS

Base from U.S. Geological Survey

digital data, 1:100,000, 1982

Universal Transverse Mercator

projection, Zone 12

35o

114o

114o30’

Hualapai Valley

A

RIZONA

C

A

LIFORNIA

River

Co

do

lo

ar

1

1

1

5

EXPLANATION

BASIN FILL

GRANITIC ROCKS

METAMORPHIC ROCKS

VOLCANIC ROCKS

SEDIMENTARY ROCKS

APPROXIMATE EXTENT OF

 80-100 PERCENT FINE-

 GRAINED FACIES OF THE

 OLDER BASIN FILL—

 Generally contains 80 to

 100 percent material that

 is less than 0.0625

 millimeters in diameter

APPROXIMATE EXTENT OF

 55-80 PERCENT FINE-

 GRAINED FACIES OF THE

 OLDER BASIN FILL—

 Generally contains 55 to

 80 percent material that is

 less than 0.0625 millimeters

 in diameter

EVAPORITES—Indicate the

 presence of extensively

 interbedded evaporites

 or massive evaporite

 deposits

GENERALIZED LINE OF

 EQUAL DEPTH TO BED-

 ROCK—Shows approxi-

 mate depth to bedrock

 below land surface, in

 thousands of feet.

VALLEY DIVIDE

E

E

1
to ground water are greatest in the 

upper parts of the valleys and decrease

downgradient to within a few feet below 

the land surface near the Colorado 

River. The greatest depths to water 

are about 1,200 ft near the boundary 

between Detrital and Sacramento Valleys 

(Dillenburg, 1987; Rascona, 1991), 

and about 600 ft near Kingman in the 

Hualapai Valley (Remick, 1981).

Local ground water in consolidated 

rocks serves as a water supply in some 

areas, especially where rocks are faulted, 

fractured, and weathered (Gillespie and 

Bentley, 1971). In the Kingman area, 

volcanic rocks are locally permeable near 

two fault zones, and ground-water stored 

in the fractures has been used as part 

of the municipal water supply. Several 

springs issue from consolidated rocks and 

in some cases serve as water supplies for 

livestock and wildlife. 

Water Quality

The Arizona Department of 

Environmental Quality has completed 

baseline ground-water quality studies 

in the Detrital (Towne, 2003) and 

Sacramento Valleys (Towne and Freark, 

2001), and has begun a similar study in 

the Hualapai Valley. A total of 28 sites 

were sampled in Detrital Valley, and 48 

sites were sampled in Sacramento Valley; 

sites included wells completed in basinfill and consolidated-rock aquifers. In 

Detrital Valley, constituents for which 10 

percent or more of the samples exceeded 

State or Federal water-quality standards 

include gross alpha, nitrate, total 

dissolved solids, sulfate, and manganese. 

In Sacramento Valley, constituents for 

which 10 percent or more of the samples 

exceeded such standards include gross 

alpha, nitrate, total dissolved solids, 

fluoride, chloride, and sulfate. In both 

valleys, dissolved-solids concentrations 

exceeded the standards more than any 

other constituent. On the basis of the 

results for all samples from each valley, 

the studies concluded that ground water 

in the Detrital and Sacramento Valleys 

generally met drinking-water standards.

Planned Approach

Previous studies have provided a basic 

understanding about the hydrogeologic 

systems of Detrital, Hualapai, and 

Sacramento Valleys; however, several 

aspects need refinement and improved 

definition for optimal management 

of the ground-water resources. The 

study will begin with a compilation 

of existing information to develop a 

hydrogeologic database for the three 

valleys. In addition, field surveys will 

be conducted to update existing data 

for boreholes, wells, and water levels 

(fig. 1). Information gained in these 

efforts will be used to refine the initial 

conceptual models of the hydrogeologic 

systems of the valleys and to guide datacollection efforts in the following years. 

A preliminary assessment indicates that 

more hydrogeologic information and data 

are available for Hualapai and Sacramento 

Valleys than for Detrital Valley; therefore, 

data-collection and analysis efforts 

likely will be focused on Detrital Valley. 

Possible data-collection and analysis 

efforts include:

1. Geophysical and geological 

investigations to define geologic features 

that affect storage and flow of ground 

water. Features include structures, such 

as faults, and the thickness, lateral 

extent, and lithology of hydrogeologic 

units.

2. Determination of hydraulic properties 

of the hydrogeologic units using field 

and empirical methods.

3. Determination of ground-water 

storage and the direction and rate of 

ground-water movement using waterlevel, geometry, and hydraulic-property 

information for the hydrogeologic units.

4. Determination of ground-water 

recharge to and discharge from the 

basin-fill aquifers in each valley using 

information gained in item 3 about 

ground-water movement, as well as 

climate, water-use, and other data. 

5. Establishment of a hydrologicmonitoring network that utilizes gravity 

data and water-level data to assess changes 

in ground-water storage over time.

6. Collection and analysis of ground-water 

samples from several wells to further 

characterize the extent of high dissolvedsolids concentrations in ground water and 

their relation to hydrogeologic factors.

—David W. Anning, Marilyn E. Flynn, and 

Margot Truini 

References Cited

Anderson, T.W., Freethey, G.W., and Tucci, Patrick, 

1992, Geohydrology and water resources 

of alluvial basins in south-central Arizona 

and adjacent states: U.S. Geological Survey 

Professional Paper 1406-B, 67 p. 3 pl.

Arizona Department of Economic Security, 2005, 

2004 Estimates—Population growth, accessed 

November 21, 2005, at URL http://www.

workforce.az.gov.us/.

Arizona Department of Water Resources, 1994, 

Arizona Water Resources Assessment, Volume 

I, Inventory and Analysis and Volume II, 

Hydrologic Summary: Arizona Department of 

Water Resources, 236 p.

Dillenburg, R.A., 1987, Map showing groundwater conditions in the Detrital Wash Basin 

Area, Mohave County, Arizona—1987: Arizona 

Department of Water Resources Hydrologic Map 

Series Report Number 14, 1 pl., scale 1:125,000.

Freethey, G.W., and Anderson, T.W., 1986, 

Predevelopment hydrologic conditions in the 

alluvial basins of Arizona and adjacent parts of 

California and New Mexico: U.S. Geological 

Survey Hydrologic Investigations Atlas HA-664, 

3 pl.

Freethey, G.W., Pool, D.R., Anderson, T.W., and 

Tucci, Patrick, 1986, Description and generalized 

distribution of aquifer materials in the alluvial 

basins of Arizona and adjacent parts of California 

and New Mexico: U.S. Geological Survey 

Hydrologic Investigations Atlas HA-663, 4 pl.

Gillespie, J.B., and Bentley, C.B., 1971, 

Geohydrology of Hualapai and Sacramento 

Valleys, Mohave County, Arizona: U.S. 

Geological Survey Water-Supply Paper 1899-H, 

37 p. 2 pl. scale 1:125,000.

Laney, R.L., 1979, Geohydrologic reconnaissance of 

Lake Mead National Recreation Area—Hoover 

Dam to Temple Bar, Arizona: U.S. Geological 

Survey Open-File Report 79–689, 42 p.

Rascona, S.J., 1991, Map showing ground-water 

conditions in the Sacramento Valley Basin, 

Mohave County, Arizona—1991: Arizona 

Department of Water Resources Hydrologic Map 

Series Report Number 21, 1 pl., scale 1:125,000.

Remick, W.H., 1981, Map showing ground-water 

conditions in the Hualapai Basin area, Mohave, 

Coconino, and Yavapai Counties, Arizona—

1980: Arizona Department of Water Resources 

Hydrologic Map Series Report Number 4, 1 pl., 

scale 1:125,000.

Richard, S.M., Reynolds, S.J., Spencer, J.E., and 

Pearthree, P.A., 2000, Geologic map of Arizona:

Arizona Geological Survey, Map 35, 1 pl., scale 

1:1,000,000.

Tadayon, Saeid, 2005, Water withdrawals for 

irrigation, municipal, mining, thermoelectricpower, and drainage uses in Arizona, outside of 

Active Management Areas, 1991–2000: U.S. 

Geological Survey Scientific Investigations 

Report 2004–5293, 28 p.

Towne, D.C., 2003, Ambient groundwater quality 

of the Detrital Valley Basin—A 2002 Baseline 

Study: Arizona Department of Environmental 

Quality Open-File Report 2003–03, 65 p.

Towne, D.C., and Freark, M.C., 2001, Ambient 

groundwater quality of the Sacramento Valley 

Basin—A 1999 Baseline Study: Arizona 

Department of Environmental Quality Open-File 

Report 2001–04, 78 p.

Western Regional Climate Center, 2005, Arizona 

Climate Summaries, 2005, accessed November 

21, 2005, at URL http://www.wrcc.dri.edu/

summary/climsmaz.html.

For further information, contact:

David W. Anning

U.S. Geological Survey

Arizona Water Science Center

Northern Arizona Programs 

2255 North Gemini Drive

Flagstaff, Arizona, 86001

Email: dwanning@usgs.gov or visit 

home page at http://az.water.usgs.gov