Fish Springs Flat

258

Sevier Desert

287

Spring Valley

184

Tule Valley

257

Wah Wah Valley

256

Spring Valley

201

Patterson Valley

202

Lake Valley

183

Tippett Valley

185

Deep Creek

Valley

253

Dugway-Government

Creek Valley

259

Milford Area

284

Beaver Valley

283

Pine Valley

255

Eagle Valley

200

Beryl-Enterprise area

280

Dry

Lake

Valley

181

Parowan Valley

281

Snake Valley

254

Snake Valley

254

Snake Valley

254

TOOELE COUNTY

JUAB COUNTY

JUAB COUNTY

MILLARD COUNTY

MILLARD COUNTY

BEAVER COUNTY

WHITE PINE COUNTY

LINCOLN COUNTY

BEAVER COUNTY

IRON COUNTY

NEVADA

UTAH

6

6

93

93

21

272

174

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487

257

6

Callao

Fish Springs

National

Wildlife Refuge

Gandy

Eskdale

Garrison

Baker 39°00'

38°30'

38°00'

114°30' 114°00' 113°30' 113°00'

39°30'

0 25

0 5 10 15 20

5 10 15 20

25 30 35 KILOMETERS

Base from 1:100,000-scale U.S. Census Bureau digital data, 2000 35 MILES

Groundwater discharge areas from 1:1,000,000-scale U.S. Geological Survey digital data, 2011

Hydrographic areas from 1:1,000,000-scale U.S. Geological Survey digital data, 2009

Albers equal area conic projection, central meridian at -114°

North American Datum of 1983

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USGS site number: 390543114081801

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Well depth: 620 feet

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USGS site number: 390629113560301

Well depth: 97 feet

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USGS site number: 39105011301001

Well depth: 778 feet

Well number: 130

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USGS site number: 391205113543401

Well depth: 97 feet

Well number: 136

USGS site number: 391322114000001

Well depth: 90 feet

Well number: 139

USGS site number: 391704113312001

Well depth: 197 feet

Well number: 140

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USGS site number: 392141113585601

Well depth: 760 feet

Well number: 145

USGS site number: 392317113504201

Well depth: 98 feet

Well number: 148

USGS site number: 393345113503201

Well depth: 196 feet

Well number: 163

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USGS site number: 393440112505601

Well depth: 150 feet

Well number: 164

USGS site number: 393814113522601

Well depth: 158 feet

Well number: 171

USGS site number: 393933113214801

Well depth: 197 feet

Well number: 174

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USGS site number: 394133113493901

Well depth: Unknown

Well number: 177

USGS site number: 394905113354101

Well depth: 147 feet

Well number: 179

USGS site number: 395331113123901

Well depth: 157 feet

Well number: 188

0

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Well depth: 435 feet

Well number: 8

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EXPLANATION

Approximate area where groundwater is 

discharged as evapotranspiration

Boundary of hydrographic area

Well associated with multiple-year water-level 

records

Hydrographic area name and number

Depth to water, in feet below land surface650

655

660

665

670

675

July 1940July 1945July 1950July 1955July 1960July 1965July 1970July 1975July 1980July 1985July 1990July 1995July 2000July 2005July 2010

U.S. Geological Survey (USGS) site 

number: 382350113231901

Well depth: 1,475 feet

Well number: 3

Well site and water-level information available at 

http://nwis.usgs.gov

Beaver Valley

283

Abstract

Water-level measurements from 190 wells were used to develop a potentiometric-surface 

map of the east-central portion of the regional Great Basin carbonate and alluvial aquifer 

system in and around Snake Valley, eastern Nevada and western Utah. The map area covers 

approximately 9,000 square miles in Juab, Millard, and Beaver Counties, Utah, and White 

Pine and Lincoln Counties, Nevada. Recent (2007–2010) drilling by the Utah Geological Survey and U.S. Geological Survey has provided new data for areas where water-level 

measurements were previously unavailable. New water-level data were used to refine 

mapping of the pathways of intrabasin and interbasin groundwater flow. At 20 of these 

locations, nested observation wells provide vertical hydraulic gradient data and information related to the degree of connection between basin-fill aquifers and consolidated-rock 

aquifers. Multiple-year water-level hydrographs are also presented for 32 wells to illustrate 

the aquifer system’s response to interannual climate variations and well withdrawals.

Introduction 

The study area includes Snake Valley and surrounding areas and is located in the eastcentral portion of the regional Great Basin carbonate and alluvial aquifer system along the 

Utah-Nevada border. The carbonate and alluvial aquifer system in and around Snake Valley 

includes carbonate-rock and basin-fill aquifers defined by Reilly and others (2008, fig. 2, 

sheet 1), in the Basin and Range Province. The aquifer system is generally comprised of 

aquifers and confining units in unconsolidated basin fill, volcanic deposits in the basins, 

and volcanic, carbonate, and other consolidated-rock units in the mountain ranges that 

separate the basins. Consolidated-rock units also underlie the basins. In this study, basins 

are defined by hydrographic area (HA) boundaries. Generally, HA boundaries coincide with 

topographic basin divides (Welch and others, 2007), and most HAs represent a single watershed, including both basin fill and adjacent mountain blocks up to the topographic divide 

(Harrill and Prudic, 1998). In areas along HA boundaries, where basin fill is sufficiently 

thick or consolidated rock is permeable, the aquifers are hydraulically connected between 

HAs and “collectively constitute a significant regional groundwater resource” (Harrill and 

Prudic, 1998). In other areas, less permeable rock units likely impede groundwater flow 

between HAs. 

Portions of the Great Basin have experienced rapid population growth in recent decades 

and have some of the highest per-capita water use in the nation. The U.S. Census Bureau 

(2005) found that Nevada and Utah were among the fastest growing states in the United 

States, with a projected population increase of more than 50 percent between 2000 and 

2030. Populous urban areas in the Great Basin include Las Vegas in southern Nevada 

and the cities and towns along the Wasatch Front in Utah (fig. 1, sheet 2). The combination of rapid population growth, high water use, and arid climate in urban areas has led 

to an increased dependence upon groundwater resources during the past 60 years (Gates, 

2004; Heilweil and others, 2011) and to predictions of future water shortages (U.S. Water 

News, June 2005). This has resulted in the targeting of portions of the Great Basin, such as 

Snake Valley, for groundwater development to supply burgeoning urban areas and a recent 

increase in applications for water rights that propose to divert groundwater for use outside 

Snake Valley and adjacent HAs to meet the demands of these regional population centers.

Snake Valley and the surrounding areas include lands managed by federal and state agencies. These lands include national parks, monuments, historic sites, and wilderness areas; 

state parks, recreation areas, and wildlife refuges; and large areas managed by the Bureau 

of Land Management. Groundwater is also the primary source of water for most uses on 

these public lands. Because of the reliance upon groundwater to concurrently meet the demands of urban populations, agriculture, and native habitats, there remains ongoing interest 

in improving the understanding of groundwater flow in Snake Valley and the surrounding 

areas. 

The purpose of this report is to present maps showing an updated potentiometric-surface 

map (fig. 1) and multiple-year water-level hydrographs (fig. 2) for the study area. The map 

area covers approximately 9,000 square miles and includes HAs in Juab, Millard, and 

Beaver Counties, Utah, and White Pine and Lincoln Counties, Nevada. In addition to Snake 

Valley (HA 254), the study area includes at least portions of the following: Spring Valley 

(HA 184), Pine Valley (HA 255), Wah Wah Valley (HA 256), Tule Valley (HA 257), Fish 

Springs Flat (HA 258), and Sevier Desert (HA 287), and is almost entirely within the Great 

Salt Lake Desert regional groundwater flow system (Harrill and others, 1988). 

Several potentiometric-surface maps have been published that include the area covered 

by this map (Thomas and others, 1986, pl. 1 and 2; Wilson, 2007, pl. 1 and 2; Sweetkind 

and others, 2011b). The previous maps were constructed using water-level measurements 

spanning decades and include few water levels measured in wells completed in consolidated rock. Furthermore, water-level measurements on these maps were contoured at 

100- to 500-foot intervals to depict generalized directions of potential groundwater flow. 

Recent (2007–2010) drilling by the Utah Geological Survey and U.S. Geological Survey 

has provided 68 new observation wells at 29 separate locations. These well sites include 

18 locations where water levels in consolidated rock can be measured and 20 locations 

where nested observation wells (clusters of wells located together but screened at different 

depths) can be used to examine the direction and magnitude of vertical hydraulic gradients. 

The drilling also provided new subsurface geologic information. These data, combined 

with new wells drilled by the Southern Nevada Water Authority (SNWA), allowed for the 

construction of an updated and more detailed potentiometric-surface map of the study area 

using 50-foot contour intervals. Multiple-year hydrographs also were compiled and examined during construction of the potentiometric-surface map to better understand if the water 

levels used to construct the potentiometric-surface map are representative of long-term 

average conditions and to illustrate general trends in rising or declining groundwater levels.

Hydrogeology of the Groundwater Flow System 

Groundwater in the study area generally moves through permeable basin fill and other 

geologic formations from high-altitude recharge areas toward low-altitude discharge areas. 

Because of the large extent and geologic complexity of the groundwater flow system, the 

geologic units are grouped into simplified hydrogeologic units (HGUs) to help conceptualize the aquifer system. The HGUs in the study area extend over large areas and each includes geologic units that have similar physical characteristics with respect to their capacity 

to store and transmit water. Five regionally important consolidated-rock HGUs defined by 

Sweetkind and others (2011a) for the Great Basin carbonate and alluvial aquifer system 

were used in this study and are depicted on the potentiometric-surface map (fig. 1). These 

consolidated-rock units include: (1) a non-carbonate confining unit (NCCU), representing low-permeability Precambrian siliciclastic formations; (2) a lower carbonate aquifer 

unit (LCAU), representing high-permeability Cambrian through Devonian limestone and 

dolomite; (3) an upper siliciclastic confining unit (USCU), representing low-permeability 

Mississippian shale; (4) an upper carbonate aquifer unit (UCAU), representing high-permeability Pennsylvanian and Permian carbonate rocks; and (5) a volcanic unit (VU), representing areas of volcanic rocks with highly variable permeability. 

Large portions of the Great Basin carbonate and alluvial aquifer system are conceptualized as being hydraulically connected, where recharge that occurs through consolidated 

rock in the mountains can enter and move through basin fill in the adjoining valleys, or 

move through consolidated rock that underlies the basin fill. Aquifers in Snake Valley and 

surrounding areas typically occur in permeable portions of the basin fill, the LCAU and 

UCAU, and the VU. Throughout most of the study area, basin-fill aquifers most often 

overlie or adjoin the LCAU or UCAU. Aquifers within the LCAU and UCAU are separated 

by the intervening low-permeability shale of the USCU and underlain at depth by the lower 

permeability NCCU.

Groundwater flow in the Snake Valley area is also affected by HGU thickness, geologic 

structures, and fault-juxtaposition of HGUs with contrasting hydrologic properties. Areas 

of low hydraulic gradient are often associated with large thicknesses of the most permeable HGUs (basin fill, UCAU, and LCAU). In other areas, low hydraulic gradients can be 

attributed to a combination of factors such as large areas of discharge in areas with a flat 

land-surface topography and little recharge. In places, the lateral continuity of HGUs is disrupted by large-magnitude faults or geologic structures (anticlines and synclines), resulting 

in a complex distribution of rocks, which can alter the direction of groundwater flow paths. 

The juxtaposition of low-permeability siliciclastic-rock strata against higher permeability 

carbonate rock or basin-fill aquifers can form barriers to groundwater flow and greatly influence the shape of the potentiometric surface (Winograd and Thordarson, 1975; Thomas 

and others, 1986; McKee and others, 1998).

Data and Methods

The potentiometric-surface map of the carbonate and alluvial aquifer system (fig. 1) was 

constructed mostly from water-level measurements made during the early spring of 2010. 

In a few locations, water levels measured before or after this time period were included 

if their location provided valuable control on the potentiometric surface. In addition to 

water-level data, the distribution and magnitude of groundwater recharge and discharge 

(Masbruch and others, 2011) and the influence of geology on groundwater flow across 

HA boundaries (Sweetkind and others, 2011b) were considered in the development of the 

potentiometric-surface map.

Static (non-pumping) water-level altitudes from 190 wells were used to construct the 

potentiometric-surface contours of the carbonate and alluvial aquifer system. Water-level 

sites shown on figure 1 are symbolized by color according to the HGU that the water level 

represents. For sites where geologic or well-log information was unavailable, the HGU was 

interpreted based on the well screen interval or well depth and according to the well’s proximity to consolidated-rock outcrops. These sites are qualified as “uncertain” and designated 

by a red outline on figure 1. One hundred fifty-three wells represent water levels in basin 

fill; 59 of these wells are qualified as uncertain. The remaining 37 wells represent water 

levels in consolidated rock; 2 of these wells are qualified as uncertain (fig. 2). At 20 of the 

sites, water levels were measured in several nested wells, including 8 sites where the nested 

wells are all in either consolidated rock or basin fill, and 4 sites where the nested wells are 

screened in both basin fill and consolidated rock. Water-level data at nested well sites were 

used to examine vertical differences in hydraulic head. While one location had an upward 

vertical gradient of 0.3, vertical hydraulic gradients were generally less than 0.05. These 

small vertical gradients indicate a hydraulic connection between basin fill and consolidated 

rock. 

In addition to the potentiometric surface, water-level hydrographs are presented for 32 

wells to illustrate the groundwater system’s response to variations in recharge and discharge (fig. 2). Water-level measurements that appeared to be influenced by ongoing or 

recent pumping at the well were considered outliers and omitted from the hydrographs. 

All water-level measurements used in this report were made using calibrated steel or 

electric tapes. The accuracy of the depth-to-water measurements for most wells is within 

0.1 foot, or less, of the actual depth. However, because the land-surface altitude at many 

of the wells was determined from their location on 1:24,000-scale topographic maps, the 

altitude is only accurate to one-half of the altitude contour interval. Consequently, the uncertainty in water-level altitudes used to construct the potentiometric contours generally is 

less than 10 feet but can be as much as 50 feet for a few of the water-level measurements. 

The water-level measurements and well information used to construct the potentiometricsurface map (fig. 1) are available from the USGS for download at URL: http://pubs.water.

usgs.gov/sim/3193. The multiple-year water-level data used to construct the hydrographs 

(fig. 2) are available from the USGS National Water Information System (NWIS) database 

at URL: http://waterdata.usgs.gov/nwis. For more information about the NWIS database, 

refer to Mathey (1998). 

Groundwater Flow in the Carbonate and Alluvial Aquifer 

System

A potentiometric-surface map showing spatially interpolated contours of equal groundwater altitude (hydraulic head) was constructed to illustrate generalized horizontal hydraulic gradients affecting both intrabasin and interbasin groundwater flow in Snake Valley 

and the surrounding region (fig. 1). This map presents new data for this region of the Great 

Basin carbonate and alluvial aquifer system that allows for higher resolution potentiometric contours and a more comprehensive comparison of bedrock and alluvial aquifer water 

levels than was possible when previous potentiometric-surface maps of the area were constructed. Furthermore, the availability of new geologic information from recently drilled 

wells allowed for additional interpretation of geologic controls on the flow of groundwater.

Throughout the study area, water levels in neighboring consolidated-rock and basin-fill 

wells, and in nested observation wells, were found to be similar, indicating that consolidated-rock and basin-fill aquifers are hydraulically connected. The current map, therefore, is 

assumed to represent a single aquifer system. This assumption is consistent with the conceptualization of Sweetkind and others (2011b) in which water levels in shallow alluvium 

were considered to be in hydraulic connection with the underlying permeable bedrock.

Potentiometric-surface contours range from 5,900 feet in Spring Valley in Nevada, to 

4,350 feet in northern Snake Valley and Fish Springs Flat in Utah (fig. 1). Groundwater 

flow is assumed to occur from higher to lower water-level altitudes, generally perpendicular to the potentiometric contours. Contours indicate that groundwater flows away from the 

high-altitude Snake Range and Deep Creek Range and into the adjacent valleys. 

The potentiometric map shows a groundwater divide in southern Spring Valley just north 

of the Lincoln County/White Pine County line. North of the groundwater divide, flow is 

generally toward the center of Spring Valley and northward. South of this divide, groundwater flows southeastward, passing through the Limestone Hills at the southern end of the 

Snake Range and into Snake Valley. Water-level data are not available for the southernmost 

portion of Hamlin Valley, but groundwater is assumed to move northward away from the 

higher-altitude areas that border the southern end of Hamlin Valley.

From the southern end of the Snake Range northward to approximately the north end of 

the Conger Range in Utah, groundwater flow in Snake Valley is primarily northeastward. 

Water-level and geologic data indicate that a steeply dipping northeast-trending section 

of the USCU (mostly Chainman Shale) acts as a barrier to eastward flow and directs most 

groundwater northeastward through basin fill and carbonate rocks (UCAU and LCAU) 

toward large areas of evapotranspiration and spring discharge in northern Snake Valley. 

Geologic cross sections indicate that this USCU barrier is concealed at shallow depths 

beneath basin fill to the south of Conger Mountain (Hintze and Fitzhugh, 2002). This and 

other areas where the concealed USCU is thought to act as a barrier to groundwater flow 

are shown as heavy dashed black lines on figure 1. South of Conger Mountain, in the vicinity of Little Valley, water-level altitudes are 465 feet different on either side of the buried 

USCU, providing evidence that this feature impedes groundwater flow. The 4,892 foot 

water-level altitude (well 113) on the west side of the buried USCU is similar to waterlevel altitudes in Snake Valley north of Eskdale. The 4,427 foot water-level altitude (well 

123) on the east side of the buried USCU is similar to water-level altitudes throughout Tule 

Valley. 

The orientation of outcrops of USCU through the Burbank Hills and in the northern 

Mountain Home Range, combined with the difference in water-level altitude between 

Hamlin Valley and Pine Valley, indicate that this steeply dipping USCU acts as a nearly 

continuous north-south trending barrier for approximately 60 miles. The only break in 

the barrier seems to be south of Highway 50 in the Ferguson Desert where drillers’ logs 

indicate that the USCU may be buried beneath significant basin fill (more than 1,400 feet at 

well 100 and 300 feet at well 91). The west-to-east hydraulic gradient across the Ferguson 

Desert in basin fill is evidence that some amount of groundwater moves eastward through 

basin fill in this area.

There remains some uncertainty as to whether the northern Confusion Range (north of 

the USCU flow barrier and east of Gandy, Utah) is a significant interbasin flowpath between Snake and Tule Valleys. The bedrock separating Snake Valley from Tule Valley in 

this area is all carbonate and may be permeable. Also, potentiometric contours based on 

several water levels in the neighboring valleys suggest the potential for groundwater movement from Snake Valley through the UCAU and LCAU of the Confusion Range into Tule 

Valley, and subsequently toward Fish Springs. However, existing water-level data in this 

area are insufficient to conclude that this groundwater movement is occurring. Therefore, 

potentiometric contours across the Confusion Range are shown as dashed to indicate that 

they are inferred (fig. 1). Groundwater in the northernmost part of Snake Valley moves 

both northward to discharge by evapotranspiration along the southern edge of the Great 

Salt Lake Desert north of Callao, Utah, and eastward as indicated by the hydraulic gradient 

between the valley bottom (wells 171, 173, and 177) and the bedrock highlands to the east 

(near well 172).

Water-level data are sparse in Pine and Wah Wah Valleys, in western Sevier Desert, and 

in the Ferguson Desert area of Snake Valley. Available data, however, indicate that flow is 

generally northward through Pine and Wah Wah Valleys and westward through Sevier Desert. Potentiometric contours suggest that flow from each of these basins moves through the 

LCAU toward Tule Valley and subsequently toward Fish Springs at the north end of Fish 

Springs Flat or the Great Salt Lake Desert to the north of the map area. In Tule Valley, a 

very flat hydraulic gradient exists where water-level altitudes are approximately 4,430 feet 

for more than 50 miles paralleling the House Range in a north-south direction. This long, 

flat gradient is likely due to a combination of low recharge rates and relatively high permeability aquifer materials underlying the valley. 

The southern parts of Snake, Pine, and Wah Wah Valleys are underlain by volcanic 

rocks, and most groundwater flow occurs primarily in the unconsolidated basin fill. The 

low permeability of the intervening volcanic mountain blocks in these areas is thought to 

limit interbasin flow. However, additional water-level data are required to clarify the degree 

of connection or separation between the upgradient parts of these HAs. 

Long-Term Water-Level Fluctuations

Water levels in wells fluctuate in response to imbalances between groundwater recharge 

and discharge. Water levels rise when recharge exceeds discharge for a period of time and 

water levels decline when the opposite occurs. Water-level variations are driven by both 

natural and anthropogenic processes. Examples of natural processes include groundwater 

recharge from the infiltration of precipitation and groundwater discharge as evapotranspiration in a marsh or wetland; an example of an anthropogenic process is discharge of groundwater by withdrawal from wells. Multiple-year water-level hydrographs are presented for 

32 wells within the study area (fig. 2). All hydrographs shown are from wells completed in 

basin fill because no long-term water-level records are available for bedrock wells.

Water-level hydrographs are distinctly different in the eastern and western parts of the 

study area. In the eastern part of the study area, water-level fluctuations are minimal (less 

than about 2 feet) over the period of record for all wells in Tule Valley, Pine Valley, Wah 

Wah Valley, Fish Springs Flat, and Sevier Desert (fig. 2). The steady water levels are likely 

due to a combination of these valleys receiving little direct recharge from nearby mountains and experiencing negligible groundwater pumping. Conversely, in the western portion 

of the study area, in Spring and Snake Valleys, wells experience noticeably greater waterlevel variations. Many of the wells in these valleys are located close to areas of substantial 

mountain recharge and respond to annual recharge or multiple-year periods of above or 

below average precipitation. Wells located close to the Snake and Deep Creek Ranges (for 

example, wells 74, 139, 145, and 177) showed water-level fluctuations of 10 to 20 feet 

over periods of only a few years. The sudden water-level rise of nearly 15 feet in well 139 

illustrates a rapid response to seasonal recharge in this area. While most water levels that 

comprise the hydrographs were measured in the spring or fall of a given year, the final 

water level shown for this well was measured in the middle of June 2010 and corresponds 

directly with the period of peak snowmelt runoff in 2010, as indicated by a continuous 

streamflow record for Lehman Creek near Baker, Nevada (USGS Station 10243260). The 

magnitude of water-level variation shown in other parts of Spring and Snake Valleys is not 

as great. However, water levels in wells throughout Spring and Snake Valleys also appear 

to respond to interannual climate variations. 

Most water-level records in the study area show no distinct, long-term monotonic trends 

(rises or declines). However, in the area north of Highway 50 in Snake Valley, water levels 

in five wells (108, 114, 120, 129, and 136) have been declining since about the mid- to late1980s. Water levels in these wells rose in response to a period of above average precipitation the mid-1980s (Wilkowske and others, 2003) and reached a maximum around the late 

1980s to early 1990s. Since that time, water levels in these wells have fallen steadily and 

show little to no recovery during subsequent periods of above average precipitation (for 

example, 1996–1998 and 2004–2005). These water-level declines are most likely caused 

by groundwater withdrawal for irrigation in this area. 

Summary

Water-level measurements from 190 wells were used to develop a potentiometric-surface 

map of Snake Valley and surrounding areas in eastern Nevada and western Utah. The 

water-level map covers approximately 9,000 square miles in the east-central portion of the 

regional Great Basin carbonate and alluvial aquifer system in Juab, Millard, and Beaver 

Counties, Utah, and White Pine and Lincoln Counties, Nevada. The map includes new 

water-level data from 68 observation wells drilled during 2007–2010 at 29 locations. Most 

measurements used to construct the map were made during the spring of 2010. These data 

help to refine conceptual pathways of intrabasin and interbasin groundwater flow.

Comparison of water levels at nested observation well sites and in neighboring wells 

completed in consolidated-rock and basin fill confirm that the carbonate and alluvial 

aquifers are hydraulically connected. Potentiometric contours indicate that a groundwater 

divide exists in southern Spring Valley where groundwater moving from the mountainous 

recharge areas on both sides of the valley diverges toward the north and south. South of the 

groundwater divide, the direction of flow is southeastward around the southern end of the 

Snake Range into southern Snake Valley. Groundwater flow in Snake Valley is primarily 

northeastward. Eastward interbasin flow out of the valley is restricted by steeply dipping, 

northeast trending, siliciclastic rocks extending from the Mountain Home Range as far 

north as the Confusion Range. 

Although water-level data throughout the eastern half of the study area are sparse, the 

limited data indicate that flow is generally northward through Pine and Wah Wah Valleys, 

and westward through Sevier Desert toward Tule Valley. A distinct, nearly flat hydraulic 

gradient exists in Tule Valley where water-level altitudes do not vary significantly for more 

than 50 miles from south to north. Potentiometric contours also indicate little or no interbasin flow between the southern portions of Hamlin, Pine, and Wah Wah Valleys, possibly 

due to low permeability volcanic and siliciclastic rocks along the HA boundaries.

Long-term water-level hydrographs presented for 32 wells show minimal water-level 

fluctuations throughout the eastern part of the study area where recharge rates are low and 

where the current levels of groundwater pumping are negligible. The western portion of the 

study area experiences noticeably greater water-level variations, indicating that the aquifer 

system in this area responds to interannual climate variation and to pumping. Except for 

the area north of Highway 50 in Snake Valley, the water levels used in this study respond 

primarily to climatic conditions and have not yet shown long-term decline from well 

withdrawals.

Acknowledgments

The authors acknowledge the contributions of Victor Heilweil, David Susong, Lynette 

Brooks, Donald Sweetkind, David Prudic, and Keith Halford (U.S. Geological Survey); 

Hugh Hurlow and Stefan Kirby (Utah Geological Survey); and William Van Liew (National Park Service), who provided significant comments pertinent to the development of the 

potentiometric-surface map. Special thanks are extended to the landowners who granted 

access to their land and wells, thereby making this study possible. The authors also thank 

the Southern Nevada Water Authority for their cooperation measuring water levels and 

sharing water-level and well data.

References Cited

Buto, S.G., and Reichelt, J.C., 2009, 1:1,000,000-scale hydrographic areas of the Great Basin: U.S. 

Geological Survey, vector digital data available at http://water.usgs.gov/GIS/metadata/usgswrd/

XML/ha694c_ha1000gb.xml. 

Gates, J.S., 2004, Ground-water development in Utah and effects on ground-water levels and 

chemical quality, in Spangler, L.E., ed., Groundwater in Utah—Resource, protection, and 

remediation: Utah Geological Association Publication 31, p. 3–26.

Harrill, J.R., Gates, J.S., and Thomas, J.M., 1988, Major ground-water flow systems in the 

Great Basin region of Nevada, Utah, and adjacent states: U.S. Geological Survey Hydrologic 

Investigations Atlas HA-694-C, scale 1:1,000,000, 2 sheets.

Harrill, J.R., and Prudic, D.E., 1998, Aquifer systems in the Great Basin region of Nevada, Utah, 

and adjacent states—Summary Report: U.S. Geological Survey Professional Paper 1409–A, 66 p.

Heilweil, V.M., Sweetkind, D.S., and Susong, D.D., 2011, Introduction, chap. A of Heilweil, V.M., 

and Brooks, L.E., eds., 2011, Conceptual model of the Great Basin carbonate and alluvial aquifer 

system: U.S. Geological Survey Scientific Investigations Report 2010–5193, 191 p.

Hintze, Lehi F., and Fitzhugh, Davis D., 2002, Geologic map of the Tule Valley 30' x 60' quadrangle 

and parts of the Ely, Fish Springs, and Kern Mountains 30' x 60' quadrangles, northwest Millard 

County, Utah: Utah Geological Survey Map 186, scale 1:100,000, 2 sheets.

Masbruch M.D., Heilweil, V.M., Buto, S.G., Brooks, L.E., Susong, D.D., Flint, L.E., and Gardner, 

P.M., 2011, Groundwater budgets, chap. D of Heilweil, V.M., and Brooks, L.E., eds., 2011, 

Conceptual model of the Great Basin carbonate and alluvial aquifer system: U.S. Geological 

Survey Scientific Investigations Report 2010–5193, 191 p.

Mathey, Sharon B., ed., 1998, National Water Information System (NWIS): U.S. Geological Survey 

Fact Sheet 027–98, 2 p., accessed January 7, 2011, at http://pubs.usgs.gov/fs/FS-027-98/fs-027-

98.pdf. 

McKee, E.H., Wickham, T.A., and Wheeler, K.L., 1998, Evaluation of faults and their effect on 

ground-water flow southwest of Frenchman Flat, Nye and Clark Counties, Nevada—A digital 

database: U.S. Geological Survey Open-File Report 98–580, 16 p., 4 pl.

Peltz, L.A., Medina, R.L., and Buto, S.G., 2005, 1:750,000-scale hydrographic areas and basinwide pumpage, recharge and interbasin flow estimates of Nevada: U.S. Geological Survey, vector 

digital data available at http://water.usgs.gov/GIS/metadata/usgswrd/XML/nv_ha750nv.xml.

Reilly, T.E., Dennehy, K.F., Alley, W.M., and Cunningham, W.L., 2008, Ground-water availability in 

the United States: U.S. Geological Survey Circular 1323, 70 p.

Sweetkind, D.S., Cederberg, J.R., Masbruch, M.D., and Buto, S.G., 2011a, Hydrogeologic 

framework, chap. B of Heilweil, V.M., and Brooks, L.E., eds., 2011, Conceptual model of 

the Great Basin carbonate and alluvial aquifer system: U.S. Geological Survey Scientific 

Investigations Report 2010–5193, 191 p.

Sweetkind, D.S., Masbruch, M.D., Heilweil, V.M., and Buto, S.G., 2011b, Groundwater flow, chap. 

C of Heilweil, V.M., and Brooks, L.E., eds., 2011, Conceptual model of the Great Basin carbonate 

and alluvial aquifer system: U.S. Geological Survey Scientific Investigations Report 2010–5193, 

191 p.

Thomas, J.M., Mason, J.L., and Crabtree, J.D., 1986, Ground-water levels in the Great Basin region 

of Nevada, Utah, and adjacent states: U.S. Geological Survey Hydrologic Investigations Atlas 

HA–694–B, 2 sheets.

U.S. Census Bureau, 2005, Population projection program: U.S. Department of Commerce database, 

accessed April 21, 2005, at http://www.census.gov/ipc/www/usinterimproj/.

U.S. Water News, June 2005, Utah searches for ways to satisfy thirst of a growing state, accessed 

December 28, 2010, at http://www.uswaternews.com/archives/arcsupply/5utahsear6.html.

Welch, A.H., Bright, D.J., and Knochenmus, L.A., eds., 2007, Water resources of the Basin and 

Range carbonate-rock aquifer system, White Pine County, Nevada, and adjacent areas in Nevada 

and Utah: U.S. Geological Survey Scientific Investigations Report 2007–5261, 96 p.

Wilkowske, C.D., Allen, D.V., and Phillips, J.V., 2003, Drought conditions in Utah during 1999–

2002—a historical perspective: U.S. Geological Survey Fact Sheet 037–03, 6 p.

Wilson, J.W., 2007, Potentiometric surface maps of the carbonate-rock and basin-fill aquifers in the 

Basin and Range carbonate-rock aquifer system, White Pine County, Nevada, and adjacent areas 

in Nevada and Utah: U.S. Geological Survey Scientific Investigations Report 2007–5089, 10 p., 2 

pl.

Winograd, I.J., and Thordarson, W., 1975, Hydrogeologic and hydrochemical framework, southcentral Great Basin, Nevada-California, with special reference to the Nevada Test Site: U.S. 

Geological Survey Professional Paper 712–C, 126 p.

U.S. Geological Survey, Reston, Virginia: 2011

For more information on the USGS—the Federal source for science about the Earth, its natural and living resources, natural 

hazards, and the environment, visit http://www.usgs.gov or call 1-888-ASK-USGS

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

by the U.S. Government

Digital files available at http://pubs.usgs.gov/sim/3193/

Suggested citation:

Gardner, P.M., Masbruch, M.D., Plume, R.W., and Buto, S.G., 2011, Regional potentiometric-surface map of the Great Basin 

carbonate and alluvial aquifer system in Snake Valley and surrounding areas, Juab, Millard, and Beaver Counties, Utah, and 

White Pine and Lincoln Counties, Nevada: U.S. Geological Survey Scientific Investigations Map 3193, 2 sheets. 

Regional Potentiometric-Surface Map of the Great Basin Carbonate and Alluvial Aquifer System in Snake Valley and Surrounding Areas, Juab, Millard, and Beaver Counties, Utah, and White Pine and Lincoln Counties, Nevada

By

Philip M. Gardner, Melissa D. Masbruch, Russell W. Plume, and Susan G. Buto

2011

Scientific Investigations Map 3193

Sheet 1 of 2 U.S. Department of the Interior

U.S. Geological Survey

Figure 2. Multiple-year water-level hydrographs from selected wells in and around Snake Valley, Juab, Millard, and Beaver Counties, Utah, and White Pine and Lincoln Counties, Nevada.

Edited by T. Iki

Manuscript approved for publication November 15, 2011
Fish Springs Flat

258

Sevier Desert

287

Spring Valley

184 Tule Valley

257

Snake Valley

254

Wah Wah Valley

256

Spring Valley

201

Patterson Valley

202

Lake Valley

183

Tippett Valley

185

Deep Creek Valley

253

DugwayGovernment

Creek Valley

259

Milford Area

284

Beaver Valley

283

Pine Valley

255

Eagle Valley

200

Beryl-Enterprise area

280

Dry

Lake

Valley

181

Parowan Valley

281

Snake Valley

254

Snake Valley

254

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TOOELE COUNTY

JUAB COUNTY

JUAB COUNTY

MILLARD COUNTY

MILLARD COUNTY

BEAVER COUNTY

WHITE PINE COUNTY

LINCOLN COUNTY

BEAVER COUNTY

IRON COUNTY

NEVADA

UTAH

NEVADA

UTAH

6

6

93

93

21

272

174

893

487

257

6

50

50

50

130

Callao

Fish Springs

National

Wildlife Refuge

Gandy

Eskdale

Garrison

Baker

39°00'

38°30'

38°00'

114°30' 114°00' 113°30' 113°00'

114°30' 114°00' 113°30' 113°00'

39°30'

39°00'

38°30'

38°00'

39°30'

0 25

0 5 10 15 20

5 10 15 20

25 30 35 KILOMETERS

35 MILES Base from 1:100,000-scale U.S. Census Bureau digital data, 2000

Groundwater discharge areas from 1:1,000,000-scale U.S. Geological Survey digital data, 2011

Geology modified from 1:500,000-scale digital state geology maps, 2005

Hydrographic areas from 1:1,000,000-scale U.S. Geological Survey digital data, 2009

Albers equal area conic projection, central meridian at -114°

North American Datum of 1983

30

U.S. Department of the Interior

U.S. Geological Survey

Regional Potentiometric-Surface Map of the Great Basin Carbonate and Alluvial Aquifer System in Snake Valley and Surrounding Areas, Juab, Millard, and Beaver Counties, Utah, and White Pine and Lincoln Counties, Nevada

By

Philip M. Gardner, Melissa D. Masbruch, Russell W. Plume, and Susan G. Buto

2011

Scientific Investigations Map 3193

Sheet 2 of 2

Figure 1. Potentiometric-surface map of Snake Valley and surrounding areas in Juab, Millard, and Beaver Counties, Utah, and White Pine and Lincoln Counties, Nevada.

Conger

Mountain

Mount Moriah

Wheeler Peak

MINERAL MOUNTAINS

WAH WAH MOUNTAINS

SAN FRANCISCO MOUNTAINS

INDIAN PEAK RANGE

HOUSE RANGE

CONFUSION RANGE

CONFUSION RANGE

SNAKE RANGE

DEEP CREEK RANGE

FISH SPRINGS RANGE

THOMAS RANGE

DRUM MOUNTAINS

LITTLE DRUM MOUNTAINS

SNAKE RANGE

SCHELL CREEK RANGE

Burbank

Hills

Milford

FERGUSON DESERT

LITTLE VALLEY

CONGER RANGE

LIMESTONE HILLS

MIDDLE RANGE

HAMLIN VALLEY

Trout

Creek

Partoun

ANTELOPE VALLEY

CRICKET MOUNTAINS

MOUNTAIN

HOME

RANGE

6

5

4 3

2

1

28

67

126

127

108

177

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174

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13

29

58

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82

Area of figures 1 and 2

EXPLANATION

Approximate area where groundwater is discharged as 

 evapotranspiration

Bedrock hydrogeologic units

Volcanic unit (VU)

Upper carbonate aquifer unit (UCAU)

Upper siliciclastic confining unit (USCU)

Lower carbonate aquifer unit (LCAU)

Non-carbonate confining unit (NCCU)

Boundary of hydrographic area

Hydrographic area name and number

Water-level contour—Shows altitude at which water level would have 

stood in tightly cased wells. Contour interval variable. North American 

Vertical Datum of 1988

Dashed where inferred

Thin line shows 10-foot intermediate contour interval

Approximate location of USCU covered by basin fill

Well used for water-level measurements—Number represents “well 

number”; See downloadable well and contour data at 

http://pubs.usgs.gov/sim/3193

Well completed in basin fill

Well completed in the VU

Well completed in the UCAU

Well completed in the LCAU

Well completed in the NCCU

Red outline indicates that the hydrogeologic unit is interpreted based 

on well depth and proximity to outcrop

4550

Nevada

Utah

Reno

Salt Lake

City

Cedar City

St George

Las Vegas

White

Pine

County

Lincoln

County

Juab County

Millard

County

Beaver County

Wasatch Front

Snake Valley

254

3

Index map showing location of Snake Valley and surrounding areas in Juab, Millard, and Beaver Counties, Utah, and White Pine and Lincoln Counties, Nevada

Digital les available at http://pubs.usgs.gov/sim/3193/

Suggested citation: Gardner, P.M., Masbruch, M.D., Plume, R.W., and Buto, S.G., 2011, Regional potentiometric-surface map of 

the Great Basin carbonate and alluvial aquifer system in Snake Valley and surrounding areas, Juab, Millard, and Beaver Counties, 

Utah, and White Pine and Lincoln Counties, Nevada: U.S. Geological Survey Scientic Investigations Map 3193, 2 sheets.