U.S. Department of the Interior

U.S. Geological Survey

Fact Sheet 2015–3083

June 2016

Prepared in cooperation with the Louisiana Department of Transportation and Development 

Water Resources of Washington Parish, Louisiana

Introduction

Information concerning the availability, use, and quality 

of water in Washington Parish, Louisiana (fig. 1), is critical 

for proper water-resource management. The purpose of this 

fact sheet is to present information that can be used by water 

managers, parish residents, and others for stewardship of this 

vital resource. Information on the availability, past and current 

use, use trends, and water quality from groundwater and 

surface-water sources in the parish is presented. Previously 

published reports (see References Cited section) and data stored 

in the U.S. Geological Survey’s National Water Information 

System (http://waterdata.usgs.gov/nwis) are the primary sources 

of the information presented here. 

In 2010, about 34.55 million gallons per day (Mgal/d) of 

water were withdrawn in Washington Parish, including about 

28.10 Mgal/d from groundwater sources and 6.44 Mgal/d from 

surface-water sources1

 (table 1). Withdrawals for industrial use 

accounted for about 52 percent (17.80 Mgal/d) of the total water 

withdrawn (table 2). Other categories of use included public 

supply, rural domestic, irrigation, and livestock. Water-use data 

collected at 5-year intervals from 1960 to 2010 (fig. 2) indicated 

that water withdrawals peaked in 1975 at about 51.9 Mgal/d. 

1

Water-withdrawal data are based on estimated or reported site-specific data 

and aggregated data, which were distributed to sources. For a full description 

of water-use estimate methodology, see “Data Collection” in Sargent (2011). 

Tabulation of numbers across text and tables may result in different totals 

because of rounding; nonrounded numbers were used for calculation of totals.

0 10 20 KILOMETERS

0 10 20 MILES

MISSISSIPPI

LOUISIANA

MISSISSIPPI

ST TAMMANY

PARISH

TANGIPAHOA

PARISH

WASHINGTON

PARISH

Franklinton

Mt Hermon

Bogalusa

Varnado

Angie

Folsom

Bush

Bogue Chitto

Little Silver Creek

Lawrence Creek

Bogue Lusa Creek

Pushepatapa Creek

Pearl River

Tchefuncte River

Silver Creek

Hays Creek

25 60

10

25

438

440

10

439

31°00'

30°50'

30°40'

89°45'

90°15'

90°

EXPLANATION

Approximate altitude of base of fresh

 groundwater, in feet below National 

 Geodetic Vertical Datum of 1929 

 (modified from Smoot, 1988)—Deepest 

 freshwater contained within the Jasper

 equivalent aquifer system

 Above 2,000

 2,000 to 2,499

 2,500 to 2,999

 3,000 and deeper

Line of section (see fig. 3)

River subbasin boundary

Well for which hydrograph is shown

 (see fig. 4)

U.S. Geological Survey surface-water

 discharge site and number

U.S. Geological Survey surface-water

 quality site and number (see table 4)

Wa-158

A'A

O

C

02489500

02490105

Wa-158

Wa-13

C

02492000

02490105 C C02489500

O

O

C

07375000

Lower Pearl subbasin

Bogue Chitto subbasin

Liberty Bayou-Tchefuncta

 subbasin

Gorman

Creek

GULF OF MEXICO

WASHINGTON

PARISH

TEXAS

ARKANSAS MISSISSIPPI

LOUISIANA

A'

A

Base modified from U.S. Geological Survey digital data

Albers Equal-Area Conic projection

North American Datum of 1983

Figure 1. Location of study area, W Figure 1 ashington Parish, Louisiana.
Table 1. Water withdrawals, in million gallons per day, by source 

in Washington Parish, Louisiana, 2010 (Sargent, 2011; B.P. Sargent, 

U.S. Geological Survey, written commun., 2012).

Aquifer system or

surface-water body Groundwater Surface water

Chicot equivalent aquifer system 6.02

Evangeline equivalent

aquifer system

0.18

Jasper equivalent aquifer system 21.91

Bogue Lusa Creek 6.30

Miscellaneous streams 0.14

Total 28.10 6.44

Table 2. Water withdrawals, in million gallons per day, by use 

category in Washington Parish, Louisiana, 2010 (Sargent, 2011).

Use category Groundwater Surface water Total

Public supply 14.26 0.00 14.26

Industrial 11.50 6.30 17.80

Rural domestic 1.36 0.00 1.36

Irrigation 0.85 0.00 0.85

Livestock 0.14 0.14 0.28

Total 28.10 6.44 34.55

0

5

10

15

20

25

30

35

40

45

50

55

1960 1965 1970 1975 1980 1985 1990 1995 2000 2005 2010

Annual withdrawals, in million gallons per day

Year

Groundwater

Surface water

EXPLANATION

Figure 2

Figure 2. Water withdrawals in Washington Parish, Louisiana, 

1960–2010 (Sargent, 2011).

Groundwater Resources

The primary sources of fresh groundwater (water with a 

chloride concentration of 250 milligrams per liter [mg/L] or 

less) in Washington Parish are the regional Chicot, Evangeline, 

and Jasper equivalent aquifer systems (fig. 3). Deeper aquifers 

in the parish contain saltwater. The base of fresh groundwater 

is deepest along the southern parish line and shallowest along 

the northern parish line (fig. 1). Recharge to these aquifer 

systems is primarily by infiltration of precipitation in a large 

area extending from within Washington Parish to about 85 miles 

(mi) north of the Louisiana-Mississippi State line (Griffith, 

2003). Discharge from these aquifer systems results from well 

pumping, interaquifer flow, and flow into surface-water bodies. 

Chicot Equivalent Aquifer System

The Upland terrace aquifer is the only aquifer within the 

Chicot equivalent aquifer system that is present in Washington 

Parish. The Upland terrace aquifer is broad and near surface 

and crops out along ridges and alongside stream valleys. Grain 

size in the Upland terrace aquifer typically ranges from fine 

sand to pea gravel. The aquifer dips to the south and extends 

westward into Tangipahoa Parish and eastward and northward 

into Mississippi where it correlates with the Citronelle 

Formation (Nyman and Fayard, 1978). As the Upland terrace 

aquifer continues dipping to the south into St. Tammany Parish 

(fig. 1), it merges into and becomes the upper Ponchatoula 

aquifer (Griffith, 2003). The base of the aquifer system is about 

100 feet (ft) above the National Geodetic Vertical Datum of 

1929 (NGVD 29) at the north end of Washington Parish and 

greater than 300 ft below NGVD 29 at the southeastern parish 

boundary, and thickness generally ranges from about 100 to 

over 250 ft (Case, 1979; Tomaszewski, 2011). 

In 2009, water levels in the Chicot equivalent aquifer 

system in Washington Parish ranged from a low of about 25 ft 

above NGVD 29 in the extreme southeastern corner of the 

parish to a high of over 250 ft above NGVD 29 in north-central 

and northwestern areas of the parish (Tomaszewski, 2011). The 

general direction of groundwater flow in the Chicot equivalent 

aquifer system was southward, with localized flow direction 

towards the Bogue Chitto and Pearl and Tchefuncte Rivers 

(fig. 1). In Washington Parish, the water-level surface generally 

follows the topography (Tomaszewski, 2011). The water level 

in the Chicot equivalent aquifer system at well Wa-13, located 

in eastern Washington Parish (fig. 1), has generally fluctuated 

about 3 ft or less annually (fig. 4). 

State well-registration records listed 2,695 active water 

wells screened in the Chicot equivalent aquifer system 

in Washington Parish in 2015, including 2,472 domestic, 

136 irrigation, 79 public supply, and 8 industrial. Depths 

of these wells ranged from 20 to 470 ft below land surface, 

and reported yields have ranged from 8 to 2,000 gallons per 

minute (gal/min) (Louisiana Department of Natural Resources, 

2015). In 2010, withdrawals from the Upland terrace aquifer 

in Washington Parish totaled about 6.02 Mgal/d (table 1) and 

included less than 0.01 Mgal/d for public supply, 0.85 Mgal/d 

for irrigation, 3.80 Mgal/d for industrial use, 1.30 Mgal/d for 

rural-domestic use, and 0.07 Mgal/d for livestock (B.P. Sargent, 

U.S. Geological Survey, written commun., 2012). 
Evangeline equivalent aquifer system

Jasper equivalent

aquifer system

EAST

A'

WEST

A

400

FEET

200

NGVD 29

-200

-400

-600

-800

-1,000

-1,200

-1,400

-1,600

-1,800

-2,000

-2,200

-2,400

-2,600

-2,800

-3,000

400

FEET

200

NGVD 29

-200

-400

-600

-800

-1,000

-1,200

-1,400

-1,600

-1,800

-2,000

-2,200

-2,400

-2,600

-2,800

-3,000

GENERALIZED

SURFACE PROFILE

GENERALIZED SURFACE PROFILE

BEND IN

SECTION

BEND IN

SECTION

BEND IN

SECTION

Lower Ponchatoula aquifer

Kentwood

aquifer

Hammond aquifer

Tchefuncta aquifer

Hammond

aquifer

Amite

aquifer

Ramsay aquifer

Ramsay

aquifer

Franklinton

aquifer

?

?

?

?

?

?

?

?

?

?

WASHINGTON

PARISH

TANGIPAHOA

PARISH

Upland terrace aquifer

Chicot equivalent

aquifer system

Franklinton

aquifer

Franklinton aquifer

Ramsay aquifer

VERTICAL SCALE GREATLY EXAGGERATED 0

0 5

5

10 KILOMETERS

10 MILES

EXPLANATION

Freshwater in sand

Saltwater in sand

Clay

Lithologic contact—separates clay and sand units.

 Dashed where approximate. Queried where uncertain

Hydrogeologic contact—defines boundary between

 conjoined or merged aquifers

?

Hydrogeologic contact—defines boundary

 between aquifer systems

Figure 3. Generalized west-to-east hydrogeologic section through 

Washington Parish, Louisiana (modified from Griffith, 2003). Trace of 

section shown on figure 1. 

Evangeline Equivalent Aquifer System

The Lower Ponchatoula, Big Branch, Kentwood, Abita, 

and Covington aquifers compose the Evangeline equivalent 

aquifer system in Washington Parish. As the Kentwood aquifer 

extends southward, it divides into the Abita and Covington 

aquifers near Bogalusa. Grain size in the Evangeline equivalent 

aquifer system ranges from sand to very coarse sand. Layers of 

clay usually separate the individual aquifers (Griffith, 2003). In 

Washington Parish, the Evangeline equivalent aquifer system 

dips and thickens in a southerly direction towards the Gulf of 

Mexico. The altitude of the base of the aquifer system ranges 

from less than 300 ft below NGVD 29 in northern Washington 

Parish to over 900 ft below NGVD 29 near the southern parish 

line (Griffith, 2003). In 2003, water levels in the Kentwood 

aquifer ranged from about 225 ft above NGVD 29 in the 

northwestern corner of the parish to about 95 ft above NGVD 29 

in the extreme southeastern corner of the parish. The direction of 

groundwater flow in the Kentwood aquifer was generally to the 

southeast (Prakken, 2004). 

State well-registration records listed 108 active water 

wells screened in the Evangeline equivalent aquifer system 

in Washington Parish in 2015, including 84 domestic, 

12 irrigation, 7 public supply, 4 industrial, and 1 power 

generation. Depths of these wells ranged from 150 to 1,047 ft 

below land surface, and reported yields have ranged from 

about 1 to 1,650 gal/min (Louisiana Department of Natural 

Resources, 2015). In 2010, withdrawals from the Evangeline 

equivalent aquifer system in Washington Parish totaled about 

0.18 Mgal/d (table 1) and included about 0.05 Mgal/d for public 

supply, 0.05 Mgal/d for rural-domestic use, and 0.07 Mgal/d 

for livestock (B.P. Sargent, U.S. Geological Survey, written 

commun., 2012).

Jasper Equivalent Aquifer System

The Jasper equivalent aquifer system in Washington 

Parish comprises the Tchefuncta, Hammond, Amite, Ramsay, 

and Franklinton aquifers (fig. 3). These aquifers are generally 

composed of fine to coarse sand and generally contain 

freshwater. The base of freshwater in the parish (fig. 1) 

generally corresponds to the base of the Franklinton aquifer, 

except where the aquifer contains saltwater (Nyman and Fayard, 

1978). Layers of clay usually separate the individual aquifers; 

however, some aquifers merge with overlying and underlying 

aquifers (Nyman and Fayard, 1978; Griffith, 2003). The aquifer 

system dips and thickens in a southerly direction towards the 

Gulf of Mexico. The altitude of the base of the aquifer system 

is not well defined, but geophysical log data indicated that it 

is less than 2,300 ft below NGVD 29 in northern Washington 

Parish and deeper than about 3,000 ft below NGVD 29 near 

the southern parish line (Nyman and Fayard, 1978; Griffith, 

2003). In 2006, the general direction of flow in the Amite 

aquifer in Washington Parish was towards a withdrawal center 

at Bogalusa, and water levels ranged from about 100 ft above 

NGVD 29 in the central part of the parish to about the NGVD 

29 in Bogalusa (Fendick, 2007). Water levels at well Wa-158, 

located in eastern Washington Parish (fig. 1) and screened in 

the Amite aquifer, have fluctuated as much as 50 ft annually 

because of groundwater withdrawals at Bogalusa (fig. 4). 

State well-registration records listed 38 active water wells 

screened in the Jasper equivalent aquifer system in Washington 

Parish in 2015, including 23 public supply, 7 domestic, and

8 industrial. Depths of these wells ranged from 750 to 2,752 ft 

below land surface, and reported yields have ranged from 

about 20 to 2,900 gal/min (Louisiana Department of Natural 

Resources, 2015). In 2010, withdrawals from the Jasper 

equivalent aquifer system in Washington Parish totaled about 

21.91 Mgal/d (table 1) and included about 14.20 Mgal/d for 

public supply and 7.70 Mgal/d for industrial use (B.P. Sargent, 

U.S. Geological Survey, written commun., 2012). 

Groundwater Quality

Water-sample analysis indicated that freshwater from the 

aquifer systems described above is generally soft,2

 and median 

values were below 15 mg/L for chloride and below 175 mg/L 

for dissolved solids (table 3). Median values for temperature 

and color generally increase with increasing aquifer depth. 

Locally, concentrations of iron and manganese can greatly 

2

Hardness ranges, expressed as milligrams per liter of calcium carbonate, are 

as follows: 0–60, soft; 61–120, moderately hard; 121–180, hard; greater than 

180, very hard (Hem, 1985).
Year

2000 2002 2004 2006 2008 2010 2012 2014

Water level, in feet (ft)

-30

-20

-10

0

10

20

30

40

50

60

70

80

90

100

Well: Wa-158

Aquifer: Amite

Altitude of land surface: 97 ft above NGVD 29

Well depth: 1,414 ft below land surface 

Well: Wa-13

Aquifer: Upland terrace

Altitude of land surface: 95 ft above NGVD 29

Well depth: 156 ft below land surface

Figure 4. Water levels in well Wa-13 screened in the Upland 

terrace aquifer and well Wa-158 screened in the Amite aquifer in 

Washington Parish, Louisiana (see fig. 1 for well locations; U.S. 

Geological Survey, 2015a). Altitudes of land surface and water level 

are measured in feet (ft) relative to the National Geodetic Vertical 

Datum of 1929 (NGVD 29).

exceed the U.S. Environmental Protection Agency’s Secondary 

Maximum Contaminant Levels (SMCLs).3

 Generally, water 

samples taken from the Chicot and Evangeline equivalent aquifer 

systems were found to be slightly acidic, with median pH values 

below the lower SMCL of 6.5, whereas samples from the Jasper 

equivalent aquifer system yielded median pH values within the 

SMCL range of 6.5–8.5 standard units (table 3; U.S. Geological 

Survey, 2015d). A statistical summary of water-quality samples 

taken from the Chicot, Evangeline, and Jasper equivalent aquifer 

systems in Washington Parish is presented in table 3. 

Surface-Water Resources 

Surface-water resources of Washington Parish are divided 

into two regional drainage basins. Most of the parish is drained 

by the Pearl Basin (Hydrologic Unit Code [HUC] 031800), 

which is divided into the Bogue Chitto subbasin (HUC 

03180005) and Lower Pearl subbasin (HUC 03180004) (fig. 1). 

The southwestern corner of the parish is drained by the Liberty 

Bayou-Tchefuncta subbasin (HUC 08090201) (fig. 1), which 

is a part of the Lake Pontchartrain Basin (HUC 080902) (U.S. 

Geological Survey, 2015c).

Bogue Chitto Subbasin

The Bogue Chitto subbasin is drained by the Bogue Chitto, 

which flows southward into Washington Parish from Mississippi 

and then flows in a southeasterly direction through the parish, 

eventually flowing into the Pearl River south of the southern 

parish line. The Bogue Chitto’s tributaries include Little Silver 

Creek, Silver Creek, Hays Creek, Lawrence Creek, and other 

small streams (fig. 1). The annual average flow of the Bogue 

3

The SMCLs are nonenforceable Federal guidelines regarding cosmetic 

effects (such as tooth or skin discoloration), aesthetic effects (such as taste, odor, 

or color), or technical effects (such as damage to water equipment or reduced 

effectiveness of treatment for other contaminants) of drinking water. SMCLs 

were established as guidelines by the U.S. Environmental Protection Agency 

(2016). 

Chitto River near Bush (site number 02492000) (fig. 1) was about 

1,994 cubic feet per second (ft3

/s) from 1937 to 2014 from a 

drainage area of about 1,210 square miles (mi2

) (U.S. Geological 

Survey, 2016). 

Lower Pearl Subbasin 

The Lower Pearl subbasin is drained by the Pearl River, 

which flows southward from Mississippi and forms the 

far eastern border between Louisiana and Mississippi. The 

Pearl River is fed by Pushepatapa and Bogue Lusa Creeks in 

Washington Parish and eventually flows into the Gulf of Mexico. 

The average flow of Bogue Lusa Creek at State Highway 439 at 

Bogalusa (site number 02490105) was 117 ft3

/s during 1963–85 

(Carlson and others, 1985). In 2010, about 6.30 Mgal/d were 

withdrawn from Bogue Lusa Creek for industrial use (tables 1 

and 2). The annual average flow of the Pearl River near Bogalusa 

(site number 02489500) (fig. 1) was about 9,973 ft3

/s from 1938 

to 2014 from a drainage area of about 6,570 mi2

 (U.S. Geological 

Survey, 2016). 

Liberty Bayou-Tchefuncta Subbasin

The Liberty Bayou-Tchefuncta subbasin is drained by the 

Tchefuncte River, which forms part of the boundary between 

Washington and Tangipahoa Parishes (fig. 1) and is fed by 

Gorman Creek and other small creeks. Streamflow data are 

limited for this reach of the river; however, a downstream site on 

the Tchefuncte River near Folsom (site number 07375000; fig. 1), 

about 6.5 mi south of the southwestern corner of Washington 

Parish, recorded an average daily discharge of about 156 ft3

/s 

during 1943–2014 (U.S. Geological Survey, 2015b). 

Surface-Water Quality

Water samples analyzed during the periods 1962–94 and 

1953–95 from the Pearl River and Bogue Chitto, respectively, 

were found to be soft with respect to hardness and generally did 

not exceed SMCLs for concentrations of chloride, sulfate, or 

iron (table 4). The median pH for both rivers was slightly below 

the SMCL range of 6.5–8.5 standard units. Dissolved oxygen 

concentrations for both rivers were generally greater than 5 mg/L, 

which is considered the minimum value for a diverse population 

of fresh, warmwater biota, including sport fish (Louisiana 

Department of Environmental Quality, 2008). A statistical 

summary of selected water-quality characteristics for the Pearl 

River and Bogue Chitto is presented in table 4. 

References Cited 

Carlson, D.D., Dantin, L.J., Garrison, C.R., and Stuart, C.G., 1985, 

Water resources data, Louisiana water year 1985: Water-Data Report 

LA–85–1, 605 p.

Case, H.L., III, 1979, Ground-water resources of Washington Parish, 

Louisiana: Louisiana Department of Transportation and Development 

Water Resources Technical Report no. 18, 29 p., 7 pls. 

Fendick, R.B., Jr., 2007, Louisiana ground-water map no. 22—

Generalized potentiometric surface of the Amite aquifer and “2,800-

foot” sand of the Baton Rouge area in southeastern in Louisiana, 

June–August 2006: U.S. Geological Survey Scientific Investigations 

Map 2984, 1 sheet, accessed March 2, 2012, at http://pubs.usgs.gov/

sim/2984/.
Table 3. Summary of selected water-quality characteristics for freshwater in the Chicot, Evangeline, and Jasper equivalent aquifer 

systems in Washington Parish, Louisiana (U.S. Geological Survey, 2015d).

[Values are in milligrams per liter, except as noted. °C, degrees Celsius; PCU, platinum cobalt units; μS/cm, microsiemens per centimeter; SU, standard units; 

CaCO3, calcium carbonate; μg/L, micrograms per liter; <, less than; SMCL, Secondary Maximum Contaminant Level established by the U.S. Environmental 

Protection Agency (2016); NA, not applicable]

Temperature (°C)Color,

(PCU)

Specific 

conductance, field 

(μS/cm at 

25 °C)

pH,

field

(SU)

Hardness 

(as CaCO3

)

Chloride,

filtered

(as Cl)

Iron, 

filtered 

(μg/L as 

Fe)

Manganese, 

filtered

(μg/L as 

Mn)

Dissolved 

solids, 

filtered

 Chicot equivalent aquifer system, 1939–2015 (45 wells)

Median 20.6 2.5 30.5 5.3 13 11 <4 <0.7 115

10th percentile 19.7 0 22.5 4.8 3.6 5.3 <4 <0.2 55.8

90th percentile 22.3 8.5 111 6.2 39 25 <30.3 <9.3 120

Number of samples 17 4 16 15 21 297 14 14 3

Percentage of samples that 

do not exceed SMCLs

NA 100 NA 0 NA 100 93 100 100

 Evangeline equivalent aquifer system, 1941–89 (29 wells)

Median 21.2 7 95 6.3 16 3.1 1,300 75 102

10th percentile 20.5 0 33 6.0 7 2.1 30 11 32

90th percentile 24.4 20 119 7.2 28 4.0 2,800 200 129

Number of samples 22 21 23 23 27 29 15 12 20

Percentage of samples that 

do not exceed SMCLs

NA 86 NA 43 NA 100 40 33 100

 Jasper equivalent aquifer system, 1947–83 (38 wells)

Median 28 10 201 7.8 3 3.5 490 60 156

10th percentile 23.4 0 91 6.4 0 2.2 50 20 99.3

90th percentile 31.5 32.5 389 8.7 11 15 2,580 108 248

Number of samples 50 46 53 51 56 57 37 23 44

Percentage of samples that 

do not exceed SMCLs

NA 67 NA 73 100 100 46 48 100

SMCLs

NA 15 NA 6.5–8.5 NA 250 300 50 500

Griffith, J.M., 2003, Hydrogeologic framework of southeastern 

Louisiana: Louisiana Department of Transportation and 

Development Water Resources Technical Report no. 72, 21 p., 

18 pls. 

 Hem, J.D., 1985, Study and interpretation of the chemical 

characteristics of natural water (3d ed.): U.S. Geological Survey 

Water-Supply Paper 2254, 264 p., accessed February 20, 2013, at 

http://pubs.er.usgs.gov/publication/wsp2254.

Louisiana Department of Environmental Quality, 2008, Environmental 

Regulatory Code, Title 33, Part IX, Subpart 1: Baton Rouge, 

Louisiana Department of Environmental Quality, accessed June 9, 

2009, at http:www.deq.louisiana.gov/portal/tabid/1674/Default.aspx.

Louisiana Department of Natural Resources, 2015, Strategic Online 

Natural Resources Information System (SONRIS): Louisiana 

Department of Natural Resources database, accessed March 3, 2015, 

at http://sonris.com/.

Nyman, D.J., and Fayard, L.D., 1978, Ground-water resources of 

Tangipahoa and St. Tammany Parishes, southeastern Louisiana: 

Louisiana Department of Transportation and Development, Office of 

Public Works Water Resources Technical Report no. 15, 76 p. 

Prakken, L.B., 2004, Louisiana ground-water map no. 17—Generalized 

potentiometric surface of the Kentwood aquifer system and the 

“1,500-foot” and “1,700-foot” sands of the Baton Rouge area in 

southeastern Louisiana, March–April 2003: U.S. Geological Survey 

Scientific Investigations Map 2862, 2 sheets, accessed February 24, 

2012, at http://pubs.er.usgs.gov/publication/sim2862.

Sargent, B.P., 2011, Water use in Louisiana, 2010: Louisiana 

Department of Transportation and Development Water Resources 

Special Report no. 17, 133 p. 

Smoot, C.W., 1988, Louisiana hydrologic atlas map no. 3—Altitude 

of the base of freshwater in Louisiana: U.S. Geological Survey 

Water-Resources Investigations Report 86–4314, 1 sheet, accessed 

November 2, 2011, at http://pubs.er.usgs.gov/publication/wri864150.

Tomaszewski, D.J., 2011, Water-level surface in the Chicot equivalent 

aquifer system in southeastern Louisiana, 2009: U.S. Geological 

Survey Scientific Investigations Map 3173, 2 pls., accessed February 

24, 2012, at http://pubs.usgs.gov/sim/3173/.

U.S. Environmental Protection Agency, 2016, Secondary Drinking 

Water Standards: Guidance for Nuisance Chemicals, accessed April 

13, 2016, https://www.epa.gov/dwstandardsregulations/secondarydrinking-water-standards-guidance-nuisance-chemicals. 
Table 4. Summary of selected water-quality characteristics for the Pearl River near Bogalusa and the Bogue Chitto River near Bush, 

Louisiana (U.S. Geological Survey, 2015d).

[Values are in milligrams per liter, except as noted. μS/cm, microsiemens per centimeter; °C, degrees Celsius; SU, standard units; CaCO3, calcium carbonate; μg/L, 

micrograms per liter; SMCL, Secondary Maximum Contaminant Level established by the U.S. Environmental Protection Agency (2016); NA, not applicable]

Specific

conductance,

field

(μS/cm

at 25 °C)

Oxygen,

dissolved

pH,

field

(SU)

Hardness 

(as 

CaCO3

)

Calcium,

filtered

(as Ca)

Magnesium,

filtered

(as Mg)

Sodium,

filtered

(as Na)

Chloride,

filtered

(as Cl)

Sulfate,

filtered

(as SO4

)

Iron,

filtered

(μg/L as 

Fe)

Pearl River near Bogalusa, 1962–941

Median 71 8.2 6.4 14 3.8 1.1 6.9 7.9 8.0 200

10th percentile 52 6.8 5.9 10 2.3 0.6 4.3 4.6 4.0 90

90th percentile 92 10.5 7.0 18 5.0 1.6 11 12 12 360

Number of samples 366 171 359 334 334 334 331 332 333 86

Percentage of samples 

that do not exceed 

SMCLs

NA NA 41 NA NA NA NA 100 100 83

Bogue Chitto River near Bush, 1953–952

Median 44 8.2 6.4 9 2.0 0.9 4.0 6.1 2.1 200

10th percentile 37 7.0 5.9 7 1.6 0.5 2.7 4.1 1.0 90

90th percentile 48 10.0 6.9 10 2.7 1.1 5.1 7.6 4.3 280

Number of samples 177 160 188 187 175 175 173 185 181 78

Percentage of samples 

that do not exceed 

SMCLs

NA NA 46 NA NA NA NA 100 100 96

SMCLs

NA NA 6.5–8.5 NA NA NA NA 250 250 300

1

Site number 02489500.

2

Site number 02492000.

U.S. Geological Survey, 2015a, Ground-water levels for Louisiana: 

National Water Information System Web Interface, accessed 

November 15, 2015, at http://nwis.waterdata.usgs.gov/la/nwis/

gwlevels.

U.S. Geological Survey, 2015b, National Water Information System—

Web interface: Accessed March 18, 2015, at http://waterdata.usgs.gov/

nwis.

U.S. Geological Survey, 2015c, Science in your watershed: Accessed 

May 1, 2015, at http://water.usgs.gov/wsc/.

U.S. Geological Survey, 2015d, Water-quality samples for Louisiana: 

National Water Information System Web Interface, accessed 

November 15, 2015, at http://nwis.waterdata.usgs.gov/la/nwis/qwdata/.

U.S. Geological Survey, 2016, Annual water-data reports 2010: USGS 

Water Resources of the United States, Publications—Annual Water 

Data Reports, accessed February 5, 2016, at http://wdr.water.usgs.gov/. 

This fact sheet was published by the U.S. Geological 

Survey in cooperation with the Louisiana Department 

of Transportation and Development (DOTD). 

Thanks are given to Zahir “Bo” Bolourchi, Director, 

Water Resources Programs, Louisiana DOTD, who 

contributed to the content of the fact sheet.

By Vincent E. White and Lawrence B. Prakken

For additional information, contact: 

Director, USGS Lower Mississippi-Gulf Water Science Center

3535 S. Sherwood Forest Blvd., Suite 120

Baton Rouge, LA 70816

E-mail: gs-w-lmg_center_director@usgs.gov

Fax: (225) 298–5490

Telephone: (225) 298–5481

Home Page: http://la.water.usgs.gov

ISSN 2327-6916 (print)

ISSN 2327-6932 (online)

http://dx.doi.org/10.3133/fs20153083