Kansas High Plains Aquifer: Kansas High Plains Aquifer: Analysis of 2005 Water Analysis of 2005 Water

LevelsLevels

Geoffrey C. BohlingGeoffrey C. Bohling

Brownie WilsonBrownie Wilson

Geohydrology SectionGeohydrology Section

Annual Measurement ProgramAnnual Measurement Program

High Plains Aquifer water levels measured High Plains Aquifer water levels measured annually by KGS and KDA-DWR since annually by KGS and KDA-DWR since 19971997

Evolved from USGS measurement Evolved from USGS measurement programprogram

Measured in winter (January) to minimize Measured in winter (January) to minimize effects of irrigation on measurementseffects of irrigation on measurements

Designed to monitor changes and identify Designed to monitor changes and identify regional trends in water tableregional trends in water table

Well Locations and HPA ExtentWell Locations and HPA Extent1 well every 16 square miles

Current monitoring network for HPA has 1348 wells

Measurement Responsibility, 2004Measurement Responsibility, 2004

Measurement Responsibility, 2005Measurement Responsibility, 2005

Generalized N-S Cross-sectionGeneralized N-S Cross-section

From High Plains Aquifer Atlas: http://www.kgs.ku.edu/HighPlains/atlas/

Data Collection: WaterWitch/WaterBugData Collection: WaterWitch/WaterBug

GPS Site Location with WaterWitchGPS Site Location with WaterWitch

On-site Data Entry With WaterBugOn-site Data Entry With WaterBugWater Bug

Wizard DatabaseWizard Database

http://www.kgs.ku.edu/Magellan/WaterLevels/index.html

Winter 2005 MeasurementsWinter 2005 Measurements

1267 wells: 715 DWR, 552 KGS1267 wells: 715 DWR, 552 KGS Most measurements made in Jan. 2005, Most measurements made in Jan. 2005,

but range from Dec. 2004 – Feb. 2005but range from Dec. 2004 – Feb. 2005 Repeat measurements at 53 wells for Repeat measurements at 53 wells for

quality controlquality control 968 irrigation wells, 233 observation wells, 968 irrigation wells, 233 observation wells,

rest other usesrest other uses

Statistical Quality ControlStatistical Quality Control

Analysis of variance to detect unwanted Analysis of variance to detect unwanted sources of variation in measurementssources of variation in measurements Measurer, ease of access, well use, oil on Measurer, ease of access, well use, oil on

water, weighted tape, chalk cut quality, water, weighted tape, chalk cut quality, aquifer groupaquifer group

Use 1-year declines to factor out strong Use 1-year declines to factor out strong spatial correlation of measured depthsspatial correlation of measured depths

Conclusion: Aquifer group only significant Conclusion: Aquifer group only significant source of variation (more later)source of variation (more later)

FIRN

SUBA

TH

LG

FO

NS

RA

SH

EL

PLCN

BT

CA

SG

GO TR

NT

KE

ME

SD

HM SF

DC

MN

GY

MP

GH

SM

RO

LEGL

WA

HP

KM

HG

SV

PN

STPR

SC

CMMT

RC

RH

EW

KW

ED

WH

HSGT

SW

HV

Elevation (feet)

High : 3885

Low : 1285

0 50 10025 Miles

0 70 14035 Kilometers

³

2005 Water Table Elevation2005 Water Table Elevation

Crossvalidation of InterpolationCrossvalidation of Interpolation

1000 1500 2000 2500 3000 3500 4000

True Water Table Elevation (fasl)

1000

1500

2000

2500

3000

3500

4000

Est

imat

ed W

ater

Tab

le E

leva

tio

n (

fasl

)

correlation: 0.9993

rms error: 22.0 ft

FIRN

SUBA

TH

LG

FO

NS

RA

SH

EL

PLCN

BT

CA

SG

GO TR

NT

KE

ME

SD

HM SF

DC

MN

GY

MP

GH

SM

RO

LEGL

WA

HP

KM

HG

SV

PN

STPR

SC

CMMT

RC

RH

EW

KW

ED

WH

HSGT

SW

HV

StandardDeviation(feet)

< 15.4

15.4 - 18

18 - 20

> 20

0 50 10025 Miles

0 70 14035 Kilometers

³

Interpolation Error Map, 2005 WTEInterpolation Error Map, 2005 WTE

2004 to 2005 Declines2004 to 2005 Declines

-15 -10 -5 0 5 10 15

Water Level Decline, 2004 to 2005 (feet)

0

100

200

300

400

Co

un

t

min: -23.1 ft

mean: 0.15 ft

median: 0.19 ft

max: 18.3 ft

FIRN

SUBA

TH

LG

FO

NS

RA

SH

EL

PLCN

BT

CA

SG

GO TR

NT

KE

ME

SD

HM SF

DC

MN

GY

MP

GH

SM

RO

LEGL

WA

HP

KM

HG

SV

PN

STPR

SC

CMMT

RC

RH

EW

KW

ED

WH

HSGT

SW

HV

Decline (feet)

Under -2

-2 to -1

-1 to 0

0 to 1

1 to 2

2 to 3

3 to 4

Over 4

0 50 10025 Miles

0 70 14035 Kilometers

³

Map of 2004 to 2005 DeclinesMap of 2004 to 2005 Declines

1-Year Declines by Aquifer Group1-Year Declines by Aquifer Group

QA QT TO QK KK

Aquifer Group

-10

-8

-6

-4

-2

0

2

4

6

8

10

2004

to

200

5 D

eclin

e (f

eet)

-0.26 ft 0.53 ft 0.01 ft -0.82 ft0.33 ft

2000 to 2005 Declines2000 to 2005 Declines

-40 -30 -20 -10 0 10 20 30 40

Water Level Decline, 2000 to 2005 (feet)

0

50

100

150

200

250

300

Co

un

t

min: -29.3 ft

mean: 5.47 ft

median: 3.80 ft

max: 42.2 ft

Map of 2000 to 2005 DeclinesMap of 2000 to 2005 Declines

FIRN

SUBA

TH

LG

FO

NS

RA

SH

EL

PLCN

BT

CA

SG

GO TR

NT

KE

ME

SD

HM SF

DC

MN

GY

MP

GH

SM

RO

LEGL

WA

HP

KM

HG

SV

PN

STPR

SC

CMMT

RC

RH

EW

KW

ED

WH

HSGT

SW

HV

Decline (feet)

Under -2

-2 to -1

-1 to 0

0 to 1

1 to 2

2 to 5

5 to 10

10 to 15

Over 15

0 50 10025 Miles

0 70 14035 Kilometers

³

1995 to 2005 Declines1995 to 2005 Declines

-60 -50 -40 -30 -20 -10 0 10 20 30 40 50 60

Water Level Decline, 1995 to 2005 (feet)

0

50

100

150

200

250

Co

un

t

min: -47.3 ft

mean: 5.84 ft

median: 2.97 ft

max: 59.4 ft

Map of 1995 to 2005 DeclinesMap of 1995 to 2005 Declines

FIRN

SUBA

TH

LG

FO

NS

RA

SH

EL

PLCN

BT

CA

SG

GO TR

NT

KE

ME

SD

HM SF

DC

MN

GY

MP

GH

SM

RO

LEGL

WA

HP

KM

HG

SV

PN

STPR

SC

CMMT

RC

RH

EW

KW

ED

WH

HSGT

SW

HV

Decline (feet)

Under -5

-5 to -2

-2 to -1

-1 to 0

0 to 1

1 to 2

2 to 5

5 to 10

10 to 15

15 to 30

Over 30

0 50 10025 Miles

0 70 14035 Kilometers

³

Decline Rate ComparisonDecline Rate Comparison

-7 -6 -5 -4 -3 -2 -1 0 1 2 3 4 5 6 7

Decline Rate (feet/year)

0

10

20

30

40

0

10

20

30

40

0

10

20

30

40

Per

cen

t

2004 to 2005

2000 to 2005

1995 to 2005

min: - 4.73

mean: 0.58

median: 0.30

max: 5.94

min: - 5.87

mean: 1.09

median: 0.76

max: 8.44

min: - 23.09

mean: 0.15

median: 0.19

max: 18.27

Five-Year Average DeclinesFive-Year Average Declines

2000 2001 2002 2003 2004 2005

Measurement Year

1

2

3

4

5

Ave

rag

e D

eclin

e O

ver

Pre

ced

ing

5 Y

ears

(fe

et)

PrecipitationPrecipitationInterpolated Total Annual and Seasonal Precipitation

High Plains Aquifer Region, Kansas1996 to 2004

0

5

10

15

20

25

30

1996 1997 1998 1999 2000 2001 2002 2003 2004

Year

Inch

es

Annual Seasonal

ConclusionsConclusions

Measurement program is very reliableMeasurement program is very reliable Average 2004 to 2005 decline (0.15 feet) Average 2004 to 2005 decline (0.15 feet)

significantly less than average decline rate significantly less than average decline rate over past five (1.09 feet/year) or ten (0.58 over past five (1.09 feet/year) or ten (0.58 feet/year) yearsfeet/year) years

Due at least in part to precipitationDue at least in part to precipitation But declines still persist, still strong in But declines still persist, still strong in

some areassome areas

From High Plains Aquifer Atlas: http://www.kgs.ku.edu/HighPlains/atlas/

The Aquifer Formerly Known as OgallalaThe Aquifer Formerly Known as Ogallala

Responsible Agency, 2004 & 2005Responsible Agency, 2004 & 2005

Measurement ProceduresMeasurement Procedures

Well locations verified with GPSWell locations verified with GPS Depths measured with chalked steel tapeDepths measured with chalked steel tape Measurements, info entered on-site using Measurements, info entered on-site using

WaterWitch/WaterBug softwareWaterWitch/WaterBug software Repeat measurements for quality controlRepeat measurements for quality control Efficient routing of teams for rapid Efficient routing of teams for rapid

completion (Jan. 8-13, 2005 for KGS)completion (Jan. 8-13, 2005 for KGS)