identifying water-quality domains near ichetucknee springs, columbia county, florida

Identifying Water-Quality Identifying Water-Quality Domains near Ichetucknee Domains near Ichetucknee Springs, Columbia County, Springs, Columbia County,

FloridaFlorida

By Sam B. Upchurch, Jim Schneider,

Kyle M. Champion, David Hornsby,

Ron Ceryak, and Warren Zwanka

1st magnitude springs in the Suwannee Basin

Ichetucknee Springs

Cody Scarp

Lake City

Location of wells and springs within the study area

Methods of Investigation

Factor Analysis

Hierarchical Analysis

Star Diagrams

WATEQ4F

Factor Analysis

• Six factors explain ~ 76% of total

variance.

• Factor I - Alkalinity, Spec. Cond., Calcium, & TDS (dissolution of calcite)

• Factor II – Silica, Magnesium, Fluoride, & Sodium (weathering of Hawthorn Group clays)

• Factor III- Ammonia & TOC (organic-rich recharge)

Factor Analysis

• Factor IV – Chloride, Sulfate,

& Potassium (deep flow)

• Factor V – Phosphorus, (-pH), & Sodium (well construction?)

• Factor VI – Iron, (-Nitrate) & Temperature (shallow/deep flow or recharge)

Factor I – Alkalinity, Calcium, Spec. Cond., & TDS

Low scores in Cody Scarpsuggests rapid recharge

Factor II – Silica, Magnesium, Fluoride, & Sodium

Highest scores in Highlands

Factor IV – Chloride, Sulfate Potassium, & TDS

Highest scores near streamsand possibly deep flow

Star Diagrams

• Graphic representation of six water-quality factors.

• Three water-quality domains

1) Northern Highlands

2) Discharge zones along major streams/rivers

3) Gulf Coast Lowlands

Star Diagrams

AlkCl

MgNO3

NH3

P

Alk

Mg

Alk

NO3

NH3

Alk

P

Star Diagrams

2

3

4

5

67 8

910 11

1213

14

16

17

1819

20

21

22

23

24

25

92

93

94

95 96

97

AlkCl

MgNO3

NH3

P

Star Diagrams

31

3233

39

40

41

48

49

5051

52

53

54

55

5657

58

59

6061

62

63

64

6768

69

70

71

72

73

7475

76

77

78

79

80

81

82

83

84

85

86

87

88

B

C

D

E

F

A

AlkCl

MgNO3

NH3

P

Hierarchical Analysis

• Using factor variables, cluster samples into similar groupings.

• Factor variables included:Alkalinity, chloride, magnesium,

nitrate, ammonia, and phosphorus

• Clustering suggests three distinct water-quality groupings within the study area.

Dendogram for water-quality data in the study area

A

B

C D

E F

Water-quality data in the study area

E

D

C

F

CC F

ED D

CA

A

D

F

DD

F

E

D

F

F

F

D A

D E

F

F

ED

E

E

A

A

D

D

D

D DB

D

B

B

93

F

B D

E

AlkCl

MgNO3

NH3

P

Water-quality data in the study area

E

DD

E

D

D

D

E

DE

E

D

D

D

DF

E

E

DE

E

E

E

CC

C

D

D

D

D

DD

D

E

D

D

C

F

D

E

E

C

C

E

C

D

C

C

C

C

D

AlkCl

MgNO3

NH3

P

Water quality at the springs

• Factor analysis indicates similarity in ground-water chemistry

• Hierarchical analysis places springs in one major cluster.

• Similarity of star diagrams suggests local recharge origin/flowpaths

WATEQ4F Analysis

• At or near saturation w/ respect to calcite

• Undersaturated in areas of the Cody Scarp

• Greatest saturation occurs along Suwannee/Sante Fe river corridors

Saturation indices in the study area

Summary

• Six factors account for more than 76% of the variability.

• Factors are tied to water-rock interactions, recharge characteristics, and flow-paths in the aquifer.

• Three major water-quality domains characterize the Ichetucknee Springs ground-water basin.

Summary

• Domains extend over a wide range and overlap to some degree.

• Using star diagrams, distinct water-quality domains are evident near the springs.

• Much of the ground-water in the region is at or near saturation, except for areas in and near the Cody Scarp.

Questions