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Suggested citation:

Hansen, C.V., 2009, Status of groundwater levels and storage volume in the Equus

Beds aquifer near Wichita, Kansas, January 2009: U.S. Geological Survey Scientific Investigations Map 3087, 1 sheet.

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Status of Groundwater Levels and Storage Volume in the Equus

Beds Aquifer Near Wichita, Kansas, January 2009

By

Cristi V. Hansen

2009

Introduction

Beginning in the 1940s, the Wichita well field was developed in the Equus Beds 

aquifer in southwestern Harvey County and northwestern Sedgwick County to supply 

water to the city of Wichita (Williams and Lohman, 1949). In addition to supplying 

drinking water to the largest city in Kansas, the other primary use of water from the 

Equus Beds aquifer is to irrigate crops in this agriculture-dominated part of southcentral Kansas (Rich Eubank, Kansas Department of Agriculture, Division of Water 

Resources, oral commun., 2008). The decline of water levels in the aquifer were noted 

soon after the development of the Wichita well field began (Williams and Lohman, 

1949). As water levels in the aquifer decline, the volume of water stored in the aquifer 

decreases and less water is available to supply future needs. For many years the U.S. 

Geological Survey (USGS), in cooperation with the city of Wichita, has monitored 

these changes in water levels and the resulting changes in storage volume in the Equus

Beds aquifer as part of Wichita’s effort to effectively manage this resource. In 2007, 

the city of Wichita began using Phase I of the Equus Beds Aquifer Storage and Recovery (ASR) project for large-scale artificial recharge of the Equus Beds aquifer. The 

ASR project uses water from the Little Arkansas River—either pumped from the river 

directly or from wells in the riverbank that obtain their water from the river by induced 

infiltration—as the source of artificial recharge to the Equus Beds aquifer (City of 

Wichita, 2009).

Hydrogeology of the Study Area

The study area (fig. 1) includes about 165 square miles (mi2) and is located in 

Harvey and Sedgwick Counties northwest from Wichita, Kansas. The study area is 

bounded on the southwest by the Arkansas River and on the northeast by the Little 

Arkansas River. There is little topographic relief in the study area. For the most part, 

the land surface slopes gently toward the major streams in the study area. The central part of the study area (fig. 1), which covers about 55 mi2

, is the historic center of 

pumping in the study area. The central part of the study area includes wells used to 

supply water to the city of Wichita and many wells used for irrigation. 

Quaternary deposits occur throughout the study area primarily as alluvial deposits. These alluvial deposits, known locally as the Equus beds, are as much as 250 feet 

(ft) thick in the study area (Leonard and Kleinschmidt, 1976). The Equus beds primarily consist of sand and gravel interbedded with clay or silt, but locally may consist 

primarily of clay with thin sand and gravel layers (Lane and Miller, 1965a; Myers and 

others, 1996). The middle part of the deposits generally has more fine-grained material 

than the lower and upper parts (Lane and Miller, 1965b, Myers and others, 1996). The 

Wellington Formation of Permian age underlies the Quaternary deposits in the study 

area and forms the bedrock confining unit below these deposits; it is about 700 ft thick 

(Bayne, 1956). In the study area, the Equus Beds aquifer consists of the Equus beds 

deposits.

The Equus Beds aquifer is the easternmost extension of the High Plains aquifer in 

Kansas (Stulken and others, 1985; Hansen and Aucott, 2001). The Equus Beds aquifer 

is an important source of groundwater because of the generally shallow depth to the 

water table, the large saturated thickness, and generally good water quality. Near the 

Arkansas River, the water table may be as little as 10 ft below land surface. Farther 

from the Arkansas River and near the Little Arkansas River, the water table is at a 

greater depth, depending on the altitude of the land surface and the amount of waterlevel decline that has been caused by groundwater withdrawals. The saturated thickness of the Equus Beds aquifer within the study area ranges from about 75 ft near the 

Little Arkansas River to almost 250 ft near the Arkansas River where the lowest areas 

of the underlying bedrock surface occur (Spinazola and others, 1985). The Equus Beds 

aquifer is considered to be an unconfined aquifer, but the presence of clay layers has 

resulted in semi-confined conditions in some areas (Spinazola and others, 1985; Stramel, 1967). Storage volume (the amount of water available for use) of the Equus Beds 

aquifer in the study area in 2006 was estimated at about 2,100,000 acre-feet (acre-ft) 

(Hansen, 2007).

Methods

The January 2009 water-level measurements were collected during January 2 to 

30, 2009, from 113 historic observation wells and 38 areal index wells. The historic 

observation wells have been used by the city of Wichita for monitoring water levels in 

the Equus Beds aquifer since the 1940s (Stramel, 1956). The areal index wells were 

installed in 2001 and 2002 to monitor the effects of artificial recharge on the water 

quality and water levels in the Equus Beds aquifer and to determine if there are waterquality differences between the shallow and deep parts of the aquifer (Andrew Ziegler, 

U.S. Geological Survey, oral commun., September 2003). Water levels in the historic 

observation wells were measured by city of Wichita personnel; water levels in the 

areal index wells were measured by Equus Beds Groundwater Management District 

No. 2 (GMD2) personnel. Both agencies used standard water-level measurement techniques that are similar to USGS methods described in Stallman (1971). The historic 

observation well data are on file in paper and electronic form with the city of Wichita’s 

Water and Sewer Department in Wichita, Kansas; the areal index well data collected 

by GMD2 are stored in the Kansas Geological Survey’s (KGS’s) Water Information 

and Storage and Retrieval Database (WIZARD) and are available at the following 

URL: http://www.kgs.ku.edu/Magellan/WaterLevels/index.html The water-level data 

used in this report from the historic monitoring wells and the areal index wells also are 

stored by the USGS in the National Water Information System (NWIS) database and 

are available at the following URL: http://waterdata.usgs.gov/ks/nwis

The water-level change since August 1940 at a well was determined by subtracting the depth to water below land surface in January 2009 from the depth to water 

below land surface at the same well in August 1940. Of the 151 wells used in this 

report, 38 had measured water levels for August 1940 and 113 did not. If an August 

1940 water-level measurement did not exist for a well in the study area, one was estimated from the August 1940 water-level altitude map of Stramel (1956) as modified 

by Aucott and Myers (1998). The August 1940 to January 2009 water-level change values 

for the measured wells were plotted on the map and manually contoured. 

Change in storage volume for the purposes of this report is defined as the change in 

saturated aquifer volume multiplied by the specific yield of the aquifer. A specific yield 

of 0.2 has been used to compute the changes in storage volume in the Equus Beds aquifer 

since Stramel (1956) first computed storage volume for the aquifer. The use of a specific 

yield of 0.2 was retained in this report because, as noted by Hansen and Aucott (2001), 

it is within the range of most estimates of specific yield, and because there is no general 

agreement on an average value of specific yield for the Equus Beds aquifer in the study 

area. 

The change in storage volume from August 1940 to January 2009 was computed 

using computer-generated Thiessen polygons (Thiessen, 1911) that were based on the 

measured water-level changes at wells and the manually drawn lines of equal water-level 

change. Theissen polygons apportion the water-level change at each well and the estimated value at points representing the lines of equal water-level change to the area around 

the wells and points. The volume of storage change was computed by summing the area 

of each Theissen polygon multiplied by the water-level-change value associated with the 

Theissen polygon, and then by the specific yield. To determine the storage-volume change 

since August 1940 in the whole study area and in the central part of the study area, the 

computation was done for the Theissen polygons within each of these areas. 

Changes in storage volume for periods that do not begin with August 1940 were 

calculated as the difference between changes in storage volume for August 1940 to the 

beginning of the selected time period, and for August 1940 to the end of the selected time 

period. For example, the change in storage volume for January 1993 to January 2009 was 

calculated as the change in storage volume for August 1940 to January 2009, minus the 

change in storage volume for August 1940 to January 1993. 

Groundwater Levels and Storage Volume, January 2009

Groundwater-level declines can result from a combination of factors, with the primary factors being pumpage and decreased recharge resulting from less-than-average precipitation. Droughts and other periods of less-than-average precipitation tend to decrease 

the amount of recharge available and increase demand for, and thus pumpage of, groundwater, resulting in increased water-level declines. Periods of greater-than-average rainfall 

tend to increase the amount of recharge available and decrease the demand for, and thus 

pumpage of, groundwater, resulting in water-level rises. If the water-level declines or 

rises are large enough, they may locally alter the direction of groundwater flow. An annual 

cycle of water-level declines and rises generally occurs in the study area. Typically, the 

largest water-level declines occur during the summer or fall when agricultural-irrigation 

and city pumpage are greatest (Aucott and Myers, 1998). This cycle of annual water-level 

declines is reflected in the annual fluctuation in the water levels in wells shown in 

figure 2. The consistently large seasonal water-level variations in well 104 probably are 

caused by agricultural-irrigation pumpage. 

Record to near-record water-level declines in the Equus Beds aquifer occurred in 

October 1992 and January 1993 (Aucott and Myers, 1998; Hansen and Aucott, 2001). 

Although the maximum recorded decline in storage-volume in the Equus Beds aquifer 

occurred in October 1992, the January 1993 storage-volume decline is used for comparison purposes to minimize the effect of seasonal factors on these comparisons (Hansen 

and Aucott, 2001). Recent reports have shown that since January 1993, the Equus Beds 

aquifer has been experiencing higher water levels because of near-average to greater-thanaverage precipitation and decreased city pumpage (Aucott and Myers, 1998; Hansen and 

Aucott, 2001, 2004; Hansen, 2007). Pumpage for agricultural irrigation, which can vary as 

much as 40 percent from year to year, tended to decrease in years of greater-than-average 

precipitation and increase in years of average to less-than-average precipitation (Hansen, 

2007); thus, decreased pumpage for agricultural irrigation likely contributed to the higher 

water levels only in years of greater-than-average precipitation. Water levels in wells in 

the study area have continued to remain relatively high, indicating this period of higher 

water levels that began in 1993 continued through January 2009 (fig. 2). Large-scale artificial recharge by the city of Wichita, which began in 2007, probably also has contributed to 

the continuation of these higher water levels.

Water-level changes from August 1940 to January 2009 are shown in figure 3. Water 

levels were measured in the historic observation wells by city of Wichita personnel during 

January 2 to 12, 2009, and in the areal index wells by GMD2 personnel during January 

19 to 30, 2009. Precipitation during January 2 to 12, 2009, was no more than a trace at 

all five weather stations in and near the study area (Halstead, Hutchinson, Mount Hope, 

Newton, and Wichita; fig. 1); precipitation ranged from 0.02 to 0.08 inch (in.) at these stations during January 19 to 30, 2009 ( Mary Knapp, State Climatologist, written commun. 

May 2009). Water-level changes from August 1940 to January 2009 ranged from a decline 

of 25.66 ft at well 14 in the central part of the study area to a rise of 2.80 ft at well P27 

just beyond the west edge of the study area (fig. 3). Water-level declines of 20 ft or more 

occurred in one small area around well 14 in the central part of the study area, probably 

because of pumping near this well. Surrounding the area of decline of 20 ft or more is a 

large area of water-level declines of 10 ft or more that covers much of the central part of 

the study area (where Wichita city wells are located). Water-level declines of 10 ft or more 

also occurred in a small area around Phase I recharge site RRW-3 in the northern part of 

the study area (fig. 3). Small water-level rises of less than 3 ft occurred along the western 

edge of the study area and near the Little Arkansas River. Since March 2007, when Wichita began large-scale artificial recharge, about 2,110 acre-ft of water have been artificially 

recharged into the aquifer through the six recharge sites shown in figure 3 (Wichita Water 

Utilities, written commun., 2009). The areas around the Phase I artificial recharge sites 

do not indicate any obvious effects from aritificial recharge, probably because no artificial recharge occurred during January 2009, and only about 1 acre-ft was recharged from 

November 2008 through January 2009 (Wichita Water Utilities, written commun., 2009). 

The change in storage volume in the study area from August 1940 to January 2009 

was a decrease of about 111,000 acre-ft (fig. 2, table 1). The storage volume in the study 

area in January 2009 was about 30,000 acre-ft more than in January 2008, and about 

23,000 acre-ft more than in July 2008 (table 1). From August 1940 (just before Wichita 

began pumping water from the study area), to January 1993, when near-record low 

water levels and storage volumes occurred in the study area because of a combination of 

drought conditions and increased usage, storage volume decreased by about 255,000 acreft in the study area (Aucott and Myers, 1998). The change in storage volume from January 

1993 to January 2009 represents a recovery of about 144,000 acre-ft (table 1) or about 56 

percent of the storage volume previously lost from August 1940 to January 1993. From 

August 1940 to January 2007 (when the last set of water-level measurements were made 

before large-scale artificial recharge began), storage volume decreased by about 167,000 

acre-ft (table 1). The change in storage volume from January 2007 to January 2009 

represents a recovery of about 56,000 acre-ft, or about 34 percent of the storage volume 

previously lost from August 1940 to January 2007. Precipitation in the study area during 

July 2008 to January 2009 tended to be near normal except for September, when monthly 

precipitation was about 3 in. above normal in much of the study area (http://www.srh.

noaa.gov/rfcshare/precip_analysis_new.php accessed May 2009). This near-normal to 

greater-than-normal precipitation probably contributed to the relatively high water levels, 

and thus maintenance of the substantial storage-volume recovery following the low levels 

in January 1993. Artificial recharge probably was an additional factor in the maintenance 

of the higher water levels and the storage-volume recovery seen in the study area since 

January 2007.

The change in storage volume in the central part of the study area (where Wichita city wells are located) from August 1940 to January 2009 was a decrease of about 

66,600 acre-ft (fig. 2, table 1). Storage volume in the central part of the study area in 

January 2009 was about 11,800 acre-ft more than in January 2008 and about 4,600 

acre-ft more than in July 2008 (table 1). From January 1993 to January 2009, storage 

volume in the central part of the study area increased by about 87,400 acre-ft (table 

1) or about 57 percent of the storage volume previously lost from August 1940 to 

January 1993. From January 2007 (just before large-scale artificial recharge began) 

to January 2009, storage volume in the central part of the study area increased by 

about 16,300 acre-ft or about 20 percent of the storage volume previously lost from 

August 1940 to January 2007. A comparison of the changes in storage volume for 

the central part of the study area to those for the study area as a whole indicates that 

in recent years the recovery has been maintained more consistently in the central part 

of the study area than in the study area as a whole (fig. 2). This probably is because 

city pumpage, which occurs in the central part of the study area, has remained 

less than pre-1993 levels, whereas agricultural-irrigation pumpage, which occurs 

throughout the study area, has been as much or more than pre-1993 levels in some 

years (Hansen, 2007). Artificial recharge also probably contributed to the recovery 

of water levels and storage volume seen in the central part of the study area since 

January 2007.

U.S. DEPARTMENT OF THE INTERIOR

U.S. GEOLOGICAL SURVEY

Prepared in cooperation with the

CITY OF WICHITA, KANSAS

SCIENTIFIC INVESTIGATIONS MAP 3087

Status of groundwater levels and storage volume in the Equus Beds aquifer

Hansen, C.V., 2009, Status of groundwater levels and storage 

volume in the Equus Beds aquifer near Wichita, Kansas, January 2009

References

Aucott, W.R., and Myers, N.C., 1998, Changes in ground-water levels and storage in 

the Wichita well field area, south-central Kansas, 1940–98: U.S. Geological Survey 

Water-Resources Investigations Report 98–4141, 20 p.

Aucott, W.R., Myers, N.C., and Dague, B.J., 1998, Status of ground-water levels and 

storage in the Wichita well field area, south-central Kansas, 1997: U.S. Geological 

Survey Water-Resources Investigations Report 98–4095, 15 p.

Bayne, C.K., 1956, Geology and ground-water resources of Reno County, Kansas: 

Kansas Geological Survey Bulletin 120, 130 p.

City of Wichita, 2009, Wichita area future water supply—a model program for other 

municipalities: Wichita, Kansas, accessed March 24, 2009, at http://www.wichita.

gov/CityOffices/WaterAndSewer/ProductionAndPumping/FutureWaterSupply.htm

Hansen, C.V., and Aucott, W.R., 2001, Status of ground-water levels and storage volume in the Wichita well field area, south-central Kansas, 1998–2000: U.S. Geological Survey Water-Resources Investigations Report 00–4267, 27 p.

Hansen, C.V., and Aucott, W.R., 2004, Status of ground-water levels and storage volume in the Equus Beds aquifer near Wichita, Kansas, January 2000–January 2003: 

U.S. Geological Survey Water-Resources Investigations Report 03–4298, 36 p.

Hansen, C.V., 2007, Status of ground-water levels and storage volume in the Equus

Beds aquifer near Wichita, Kansas, January 2003–January 2006: U.S. Geological 

Survey Scientific Investigations Report 2006–5321, 34 p.

Hansen, C.V., 2009, Status of ground-water levels and storage volume in the Equus

Beds aquifer near Wichita, Kansas, July 2009: U.S. Geological Survey Scientific 

Investigations Map 3075, map scale 1:84,480.

Juracek, K.E., and Hansen, C.V., 1995, Digital maps of the extent, base, top, and 

1991 potentiometric surface of the High Plains aquifer in Kansas: U.S. Geological Survey Open-File Report 95–758, map scales 1:500,000 and 1:1,000,000.

Lane, C.W., and Miller, D.E., 1965a, Geohydrology of Sedgwick County, Kansas: 

Kansas Geological Survey Bulletin 176, 100 p.

Lane, C.W., and Miller, D.E., 1965b, Logs of wells and test holes in Sedgwick 

County, Kansas: Kansas Geological Survey Special Distribution Publication 22, 

175 p.

Leonard, R.B., and Kleinschmidt, M.K., 1976, Saline water in the Little Arkansas 

River Basin area, south-central Kansas: Kansas Geological Survey Chemical 

Quality Series 3, 24 p.

Myers, N.C., Hargadine, G.D., and Gillespie, J.B., 1996, Hydrologic and chemical 

interaction of the Arkansas River and the Equus Beds aquifer between Hutchinson and Wichita, south-central Kansas: U.S. Geological Survey Water-Resources 

Investigations Report 95–4191, 100 p.

Spinazola, J.M., Gillespie, J.B., and Hart, R.J., 1985, Ground-water flow and solute 

transport in the Equus beds area, south-central Kansas: U.S. Geological Survey 

Water-Resources Investigations Report 85–4336, 68 p.

Stallman, R.W., 1971, Aquifer-test design, observation and data analysis: U.S. 

Geological Survey Techniques of Water-Resources Investigations, book 3, chap. 

B-1, p. 14–16.

Stramel, G.J., 1956, Progress report on the ground-water hydrology of the Equus

beds area, Kansas: Kansas Geological Survey Bulletin 119, part 1, 59 p.

Stramel, G.J., 1967, Progress report on the ground-water hydrology of the Equus

beds area, Kansas 1966: Kansas Geological Survery Bulletin 187, part 2, 27 p.

Stullken, L.E., Watts, K.R., and Lindgren, R.J., 1985, Geohydrology of the High 

Plains aquifer, western Kansas: U.S. Geological Survey Water-Resources Investigations Report 85–4198, 86 p.

Theissen, A.H., 1911, Precipitation averages for large areas: Monthly Weather 

Review, v. 39, p. 1082–1084.

Williams, C.C., and Lohman, S.W., 1949, Geology and ground-water resources of 

a part of south-central Kansas, with special reference to the Wichita municipal 

water supply: Kansas Geological Survey Bulletin 79, 455 p.

Conversion Factors, Abbreviations, and Datums

Multiply By To obtain

Length

inch (in.) 2.54 centimeter (cm)

inch (in.) 25.4 millimeter (mm)

foot (ft) 0.3048 meter (m)

mile (mi) 1.609 kilometer (km)

Area

square mile (mi2) 2.590 square kilometer (km2) 

Volume

acre-foot (acre-ft) 1,233 cubic meter (m3)

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

(NAVD 88).

Horizontal coordinate information is referenced to the North American Datum of 1983 

(NAD 83).

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

Figure 1. Location of study area near Wichita, south-central Kansas (modified from 

Aucott and Myers, 1998).

Study area

KINGMAN

COUNTY

Patterson

37°45'

38°

38°15'

97°45' 30' 97°15'

Arkansas

River

Kisiwa

River

Arkansas

Little

West

East

Emma 

Emma 

Creek

Sand 

Creek

Creek

Creek

RICECOUNTY

RENO

COUNTY

MARION

COUNTY

MCPHERSON

COUNTY

Approximate extent of 

High Plains aquifer in 

Kansas (from Juracek 

and Hansen, 1995)

SEDGWICK

COUNTY

HARVEY

COUNTY

Hesston

Newton

Bentley

Hutchinson

Emma

Creek

Halstead

Index map

Cheney

 Reservoir

North Fork

Ninnescah River 

KANSAS

Approximate boundary 

of Equus Beds aquifer

(from Juracek and

Hansen, 1995)

Andale

Park

City

Bel Aire

Wichita

Burrton

Central part 

of study area

Base from U.S. Geological Survey digital data, 1:100,000, 1983 

Lambert Conformal Conic Projection

Standard parallels 33° and 45°, central meridian 98°15'

Cow

Creek

Sedgwick

Mount

Hope Valley

Center

0 2 4 6 8 10 MILES

0 2 4 6 8 10 KILOMETERS

Figure 2. Water-level altitudes in observation wells 104 and 886 and Equus Beds 

aquifer storage-volume change since 1940 to January 2009 in the study area and the 

central part of the study area (water-level-altitude data from Stramel (1956, 1967), and 

from data collected by city of Wichita, Equus Beds Groundwater Management District 

No. 2, and on file with U.S. Geological Survey. Location of observation wells is shown in 

figure 3. Storage-volume changes from Stramel (1956, 1967), Aucott and Myers (1998), 

Aucott and others (1998), Hansen and Aucott (2001, 2004), Hansen (2007, 2009), and data 

on file with U.S. Geological Survey in Lawrence, Kansas).

1,300

1,440

1,310

1,320

1,330

1,340

1,350

1,360

1,370

1,380

1,390

1,400

1,410

1,420

1,430

WATER-LEVEL ALTITUDE, IN FEET ABOVE NORTH 

AMERICAN VERTICAL DATUM OF 1988 (NAVD 88)

Storage-volume 

change in study area

Water-level altitude in well 104

Water-level altitude in well 886

Storage-volume change

in central part of study area

1940

1945

1950

1955

1960

1965

1970

1975

1980

1985

1990

1995

2000

2005

2010 -300,000

-200,000

-100,000

0

100,000

200,000

300,000

400,000

STORAGE-VOLUME CHANGES, IN ACRE-FEET

Halstead

Sedgwick

Burrton

-2.36

-6.35

122

-2

+2

0

-2

-2

-6

-8

-8

-8

-10

-10

-12

-12

-12

-12

-14

-14

-14

-14

-16

-16

-18

-20

-8

0

0

0

11 12

T.

25

S.

T.

24

S.

T.

23

S.

R. 3 W. R. 2 W. R. 1 W.

Base from U.S. Geological Survey digital data, 1:100,000, 1983 

Universal Transverse Mercator projection 

Zone 14

Horizontal coordinate information is referenced to the North American

 Datum of 1983 (NAD 83)

0 1 2 3 4 5 6 MILES

0 1 2 3 4 5 6 KILOMETERS

Little

Arkansas

River

River

Emma

Emma

West

Creek

Creek

Creek

Sand

Arkansas

Mount

Hope

Burrton

Bentley

Sedgwick

Little

P32

P30

P29

118

P35

3034

892

47

109

130 41

18

26

1189

1173

1175

15

19

20

133

29

3041

P28

880

44

3035

3001

103

104

101

3 4

2

7

878

886

5

6

506

3038

8

9 16

17 1190

2084

3033

833

1187

1186

50 49

48

45

Patterson

110 3002

112

22

23

839

24 28 25

54

55

52

114

53

51

842

840 30 32 34 35

33

36

124 1176

1179

826

115 3044

37 816

38

39

40

815

126

810

3050

Arkansas

Kisiwa

1

3004

870

Creek

13

27

P27

10

46

River

14

120

-4

-4

-4

-2

-4

31

108

-16

-6

-6

-10

-6

-8

-8

P31 3036

105

HARVEY COUNTY

SEDGWICK COUNTY

-10

-22

-24

-6

-10

IW-01

IW-02

IW-08

IW-09

IW-14

IW-13

IW-18

IW-19

IW-24 IW-25

IW-30

IW-31

IW-35

IW-32

IW-33

IW-34 

IW-38

IW-37 IW-36

IW-27

IW-28

IW-29

IW-20

IW-21 IW-22 IW-23

IW-10

IW-15

IW-16

IW-17

IW-11

IW-06

IW-12

IW-05

IW-03

IW-26

IW-04

Valley

Center

42

IW-07

Halstead

-1.66

"

"

"

"

-2.13

-3.10 -3.49 -1.79

-0.81

-5.03

-2.05 -5.82

-3.89

-6.84

-9.45

-5.06

-2.84 -0.42

-2.17 -8.10

-4.64

-1.31

-5.43

-7.22

-4.26

-1.28

-8.63

-4.82

-4.12

-7.18 -8.58

-8.04

-1.37 -2.94

-2.36

-12.73

-12.47

-11.41

-15.24

-15.70

-11.10

-15.50

-8.16

3032

Boundary of 

study area

Boundary of central 

part of study area

Boundary of central 

part of study area Boundary of 

study area

"

"

"

"

"

"

!

!

!

RRW-3

RRW-4

RRW-2

RRW-1

RB-2

RB-1

111

!

!

!

+1.21

-3.02

-1.67

-7.36

-7.13

-8.69

-4.53

-1.38

-1.06 +1.32

-1.12

+0.85

-1.63

-8.18

+1.17

-5.69

+1.09

+2.80

-7.68

-6.18

-5.39

-6.32

-4.82

-6.03 -8.45

-6.66

-7.68

-6.81

-5.87

-8.77

-8.16 -6.49

-3.00

-0.74

-1.17

-9.62

-0.28

-7.60

-3.69

-6.53

-2.54 -2.96

-7.14

-3.25

-4.52

-3.55

-2.03

-3.25

-0.61

+2.17

-1.36

-2.97

-6.70

+0.15

-1.58

-1.65

-6.84

-9.15

+0.65

-7.82

-10.26

-15.83

-14.14

-16.87

-13.83

-14.05 -14.88

-13.50

-13.01

-16.79

-12.65

-19.32 -16.50

-14.08

-12.34 -12.50

-11.40

-10.99

-16.46

-11.71

-11.20 -10.19

-11.55

-12.82 -10.91

-13.72

-10.37

-11.16 -11.06

-11.68 -10.17

-12.18 -13.79

-12.27

-10.85

-11.27

-14.71

-16.28

-14.34

-10.46

-13.21

-12.52

-16.10

-18.03

-16.72

-15.33

-5.13

-25.66

-2.22

97°37'30" 30' 97°22'30"

38°

37°52'30"

-10

Water-level measurements made by city of Wichita and

Equus Beds Groundwater Management District No. 2 personnel.

Change in storage volume in study area between August 1940 

and January 2009 is -111,000 acre-feet.

RRW-1

IW-12

-1.28

16

-14.14

EXPLANATION

Area of water-level decline:

 Less than 10 feet

 10 to less than 20 feet

 20 to less than 30 feet

Line of equal water-level change—

 Interval 2 feet. Dashed where

 approximately located 

Phase 1 recharge site and identifier

Equus beds historic observation

 well—Well number shown above; 

 water-level change, in feet, shown 

 below

Well hydrograph shown in figure 2

Equus beds area index well—Well 

 identifier shown above; water-level 

 change, in feet, shown below

"

Figure 3. Water-level changes in the Equus Beds aquifer in the study area, August 1940 to January 2009.

Table 1. Storage-volume changes in Equus Beds aquifer near Wichita, southcentral Kansas, August 1940 to January 2009.

[Data on file with U.S. Geological Survey, Lawrence, Kansas.]

Time period Storage-volume changes, 

in acre-feet

In study area In central part of 

study area

August 1940 to January 1993 1-255,000 1-154,000

August 1940 to January 2007 -167,000 -82,900

August 1940 to January 2008 -141,000 -78,400

August 1940 to July 2008 2-134,000 2-71,200

August 1940 to January 2009 -111,000 -66,600

January 1993 to January 2009 +144,000 +87,400

January 2007 to January 2009 +56,000 +16,300

January 2008 to January 2009 +30,000 +11,800

July 2008 to January 2009 +23,000 +4,600

1

 Storage-volume change previously reported by Aucott and Myers (1998).

2

 Storage-volume change previously reported by Hansen (2009).