U.S. Department of the Interior

U.S. Geological Survey

Fact Sheet 2016-3101

February 2017

Prepared in cooperation with the Louisiana Department of Transportation and Development 

Water Resources of Catahoula Parish, Louisiana

Introduction

Information concerning the availability, use, and 

quality of water in Catahoula Parish, Louisiana (fig. 1), 

is critical for proper water-supply 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 

(U.S. Geological Survey, 2016) are the primary sources of 

the information presented here. 

In 2010, 30.01 million gallons per day (Mgal/d) of water 

were withdrawn in Catahoula Parish, Louisiana, including about 

22.63 Mgal/d from groundwater sources and 7.38 Mgal/d from 

surface-water sources1

 (table 1). Withdrawals for agricultural 

use, composed of aquaculture, general irrigation, livestock, and 

rice irrigation, accounted for about 93 percent (28.05 Mgal/d) 

of the total water withdrawn (table 2). Other categories of use 

included public supply and rural domestic. Water-use data 

collected at 5-year intervals from 1960 to 2010 indicated that 

water withdrawals peaked in 2000 at 30.99 Mgal/d (fig. 2). 

1

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

and aggregated data, which are 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 are used for calculation of totals.

0 10 20 MILES

0 10 20 KILOMETERS

Base modified from U.S. Geological Survey digital data

Albers Equal-Area Conic projection

North American Datum of 1983

A A'

RED RIVER LOCK

AND DAM NO. 1

Monterey

Clayton

Columbia

Sicily Island

Jonesville

Vick

Tew Lake

Larto Lake

Wallace Lake

Mean

Lake

Red River

Ouachita River

Boeuf River

Little River

Tensas River

Louis

Bayou

Black River

Tew Lake

Larto Lake

Wallace Lake

Mean

Lake

Red River

Ouachita River

Boeuf River

Little River

Tensas River

Louis

Bayou

Black River

Gastis Creek

CALDWELL

PARISH

FRANKLIN

PARISH

LASALLE

PARISH

TENSAS

PARISH

CONCORDIA

PARISH

CATAHOULA

PARISH

AVOYELLES

PARISH

Approximate altitude of base of fresh

 groundwater, in feet below National 

 Geodetic Vertical Datum of 1929 (NGVD 29) 

 (modified from Smoot, 1988)—Deepest 

 freshwater contained within the alluvial

 aquifer, except where noted

 Above 0

 0 to 99

 100 to 199

 200 to 299

 300 to 399

 400 to 499

 500 to 599

 600 to 699

 700 and deeper 

Area where intermediate sands contain saltwater

Area where no major aquifer contains freshwater

Approximate boundary of area showing deepest 

 freshwater within underlying Catahoula and 

 Cockfield aquifers 

River basin boundary

Line of section (see fig. 3)

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) 

EXPLANATION

Ct-74

07355603

07367630

A'A

32°00'

31°40'

31°20'

91°40'

92°00'

Lower Red

Basin

Lower

 Ouachita

 Basin

Lower Red

Basin

Lower

 Ouachita

Boeuf-Tensas

Basin

Alluvial

aquifer

Catahoula

aquifer

Cockfield

aquifer

84

65

28

425

129

Ct-87

Ct-347

Ct-74

Co-50

Ct-347

07367630

07367640

073556005

07355603

07373267

07367640

GULF OF MEXICO

CATAHOULA

PARISH

TEXAS

ARKANSAS MISSISSIPPI

LOUISIANA

07355500

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

in Catahoula Parish, Louisiana, 2010 (Sargent, 2011).

Aquifer or 

surface-water body Groundwater Surfacewater

Red River alluvial aquifer 0.21

Mississippi River alluvial aquifer 20.49

Catahoula aquifer 1.93

Miscellaneous streams 7.38

Total 22.63 7.38

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

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

Use category Groundwater Surface 

water Total

Public supply 1.86 0.00 1.86

Rural domestic 0.11 0.00 0.11

Livestock 0.02 0.04 0.06

Rice irrigation 11.86 0.00 11.86

General irrigation 7.34 7.34 14.68

Aquaculture 1.44 0.00 1.44

Total 22.63 7.38 30.01

1960 1965 1970 1975 1980 1985 1990 1995 2000 2005 2010

Year

Annual withdrawal, in million gallons per day

0

5

10

15

20

25

30

35

Groundwater

Surface water

EXPLANATION

Figure 2. Water withdrawals in Catahoula Parish, Louisiana, 

1960–2010 (Sargent, 2011).

Groundwater Resources 

The primary freshwater-bearing aquifers underlying 

Catahoula Parish are the alluvial and Catahoula aquifers 

(figs. 1, 3). Other aquifers containing freshwater underlying 

Catahoula Parish include the Upland terrace and Jasper aquifers 

but are not considered major sources of freshwater in the parish 

because of their limited extents (Snider and Sanford, 1981; 

Martin and others, 1988). The base of fresh groundwater (water 

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

or less) may be found in the alluvial aquifers at depths shallower 

than 100 feet (ft) below the National Geodetic Vertical Datum 

of 1929 (NGVD 29) in the northern part of the parish to deeper 

than 200 ft below NGVD 29 in the southern part of the parish. 

The base of fresh groundwater may be found at depths shallower 

than NGVD 29 in the northwestern part of the parish to deeper 

than 700 ft below NGVD 29 in the central part of the parish in the 

Catahoula aquifer (fig. 1) (Smoot, 1988). Saltwater (water with a 

chloride concentration greater than 250 mg/L) is present in some 

intermediate sands in the east-central part of the parish, and little 

to no fresh groundwater is available in the extreme northwestern 

corner of the parish (Smoot, 1988). 

Alluvial Aquifers

The alluvial aquifers are composed of sand and gravel 

deposited by streamflow in Catahoula Parish. The Mississippi 

River alluvial aquifer, which includes the Red River alluvial and 

Ouachita River alluvial aquifers, is the major aquifer underlying 

the parish. (Some classifications describe these aquifers as distinct 

but connected aquifers; see Lovelace and Lovelace, 1995.) The 

alluvial aquifer is composed of the sand and gravel component 

of sediments deposited by the rivers. In Catahoula Parish, the 

Mississippi River alluvial deposit thickness ranges from less 

than 80 ft to greater than 160 ft (Whitfield, 1975). The base of 

the aquifer generally ranges from less than about 25 ft below 

NGVD 29 in the north-central part of the parish to greater than 

200 ft below NGVD 29 in the southeastern part of the parish 

(Saucier, 1994). 

The primary source of recharge for the alluvial aquifer is 

the infiltration of precipitation, with lesser amounts of recharge 

coming from streams and rivers during high stage. Groundwater 

discharges naturally by way of flow into streams and rivers and 

evapotranspiration and artificially by way of well withdrawals 

(Whitfield, 1975).

In 1990, water levels in wells screened in the Mississippi 

River alluvial aquifer ranged from less than 50 ft above NGVD 29 

in the northern part of the parish to about 20 ft above NGVD 29 

in the south-central part of the parish (Seanor and Smoot, 1995). 

These water levels indicate that groundwater generally flows south 

to southwest in the Mississippi River alluvial aquifer in Catahoula 

Parish. Water levels in well Ct-87, located in the southern part of 

the parish and screened in the Mississippi River alluvial aquifer, 

have fluctuated annually and declined about 2 ft overall from fall 

of 1972 to fall of 2015 (fig. 4). Water levels in well Ct-74, located 

in the southern part of the parish and screened in the Red River 

alluvial aquifer, have fluctuated annually, declined during the 

late 1970s, and recovered in the early 1980s. Dewatering wells in 

operation during 1978–84 for the construction of the Red River 

Lock and Dam No. 1 caused the water-level declines in well Ct-74 

during that period (Smoot and Martin, 1991). Water levels in well 

Ct-347, located in the northern part of the parish and screened in 

the Mississippi River alluvial aquifer, have generally fluctuated 

less than 5 ft annually and declined about 8 ft from 1990 to 2016. 

State well-registration records listed 467 active water wells 

screened in the Mississippi River and Red River alluvial aquifers 

in Catahoula Parish in 2015, including 419 irrigation, 36 domestic, 

10 public supply, and 2 industrial. Depths of these wells ranged 

from 30 to 187 ft below land surface, and reported yields ranged 

from 3 to 4,300 gallons per minute (gal/min) (Louisiana 
laf15-0711_fig03

NGVD 29

-1,000

500

FEET FEET

NGVD 29

-1,000

500

BEND IN

SECTION

BEND IN

SECTION

BEND IN

SECTION

Vicksburg-Jackson

confining unit

Cockfield aquifer

Mississippi River

alluvial aquifer

Upland terrace

aquifer

Catahoula aquifer

Ouachita River

alluvial aquifer

A’

EAST

A

WEST

Freshwater in sand

Saltwater in sand—Saltwater

 contains greater than 250 milligrams

 per liter chloride 

Clay

EXPLANATION

10 MILES

0 5 10 KILOMETERS

VERTICAL SCALE GREATLY EXAGGERATED 0 5

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

Catahoula Parish, Louisiana (modified from Smoot, 1989). Trace of 

section shown on figure 1.

Department of Natural Resources, written commun., 2015). In 

2010, about 20.71 Mgal/d were withdrawn from the alluvial 

aquifers, primarily the Mississippi River alluvial aquifer, with use 

categories including 1.44 Mgal/d for aquaculture, 0.07 Mgal/d for 

rural domestic, 7.19 Mgal/d for general irrigation, 11.86 Mgal/d 

for rice irrigation, and 0.14 Mgal/d for public supply (B.P. Sargent, 

U.S. Geological Survey, written commun., 2015). 

Catahoula Aquifer

The Catahoula aquifer is present across the central part of 

the State of Louisiana and crops out in a narrow band extending 

from the Texas State line to northern Catahoula Parish. The 

aquifer contains freshwater in the parish from about Jonesville 

west to the parish line and north to near Sicily Island (fig. 1). In 

the outcrop area, the Catahoula aquifer dips to the south at a rate 

of about 50–70 ft per mile. The aquifer is composed of sands that 

are typically white to light gray, range from very coarse to very 

fine grained, are seldom areally extensive, and are interbedded 

with silts and clays. Recharge to the aquifer is from infiltration of 

precipitation in the outcrop area and flow from adjacent aquifers 

(Martin and Whiteman, 1986; Fendick and Carter, 2015). 

In 2013, water levels in wells screened in the Catahoula 

aquifer in the northwestern part of the parish were about 100 ft 

above NGVD 29 and in the central part of the parish were less 

than 20 ft above NGVD 29, indicating that groundwater in the 

aquifer generally flows to the southeast in Catahoula Parish. 

Localized levels are as high as about 80 ft above NGVD 29 under 

Sicily Island. Levels in central and north-central Catahoula Parish 

have declined about 20 ft or more from 1980 to 2015 (Martin 

and Whiteman, 1986; Fendick and Carter, 2015; U.S. Geological 

Survey, 2016). Levels in well Co-50 screened in the Catahoula 

aquifer in neighboring Concordia Parish to the east have declined 

over 45 ft during 1970–2015 (fig. 4). 

State well-registration records listed 58 active water wells 

screened in the Catahoula aquifer in Catahoula Parish in 2015, 

including 24 domestic, 1 industrial, 4 irrigation, and 29 public 

supply. Depths of these wells ranged from 124 to 798 ft below 

land surface, and reported yields ranged from 5 to 608 gal/min 

(Louisiana Department of Natural Resources, written commun., 

2015). In 2010, 1.93 Mgal/d were withdrawn from the Catahoula 

aquifer, including 0.04 Mgal/d for rural-domestic use, 0.15 Mgal/d 

for general irrigation, 0.02 Mgal/d for livestock, and 1.72 Mgal/d 

for public-supply use (B.P. Sargent, U.S. Geological Survey, 

written commun., 2015). 

Groundwater Quality

Freshwater samples taken from wells screened in the 

Mississippi River and Red River alluvial aquifers were found to 

have similar median values for pH of 7.1 and 6.9 standard units, 

respectively; similar median hardness2

 of 300 and 320 mg/L as 

calcium carbonate, respectively; and similar median magnesium 

of 28.5 and 28 mg/L, respectively (table 3). Iron concentrations 

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

Maximum Contaminant Levels (SMCLs)3

 in 71 percent of 

Mississippi River alluvial aquifer samples and 95 percent of Red 

River alluvial aquifer samples. Samples from both aquifers were 

within the very hard range for hardness. 

Freshwater samples taken from the Catahoula aquifer 

had a greater median pH (7.4 standard units) than median pH 

values in samples from the Mississippi River and Red River 

alluvial aquifers (table 3). Catahoula aquifer samples had median 

concentrations of hardness (8.5 mg/L), magnesium (0.5 mg/L), 

iron (205 micrograms per liter [μg/L]), and manganese (35 μg/L) 

that were less than median concentrations in samples from the 

Mississippi River and Red River alluvial aquifers. Little to no 

fresh groundwater is present in the far northwestern corner of the 

parish where the Vicksburg-Jackson confining unit (fig. 3) crops 

out and saltwater is present in underlying aquifers. 

Surface-Water Resources

Numerous surface-water resources in Catahoula Parish are 

present in three regional drainage basins, which are composed of 

multiple subbasins. The Boeuf-Tensas Basin (Hydrologic Unit 

Code [HUC] 080500) is present along the northern border and 

eastern border of the parish, north of Jonesville (fig. 1). The Lower 

Ouachita Basin (HUC 080402) is present in the northern interior 

of Catahoula Parish, and the Lower Red Basin (HUC 080403) 

is present in about the southern half of the parish (fig. 1; U.S. 

Geological Survey, 2016). Numerous lakes are present within 

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). 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. The SMCLs were established 

as guidelines by the U.S. Environmental Protection Agency (2016). 
laf15-0711_fig 04

1968 1972 1976 1980 1984 1988 1992 1996 2000 2004 2008 2012 2016

Year

Water level, in feet

-20

-10

0

10

20

30

40

50

60

Well: Ct-87

Aquifer: Mississippi River alluvial aquifer

Altitude of land surface: 51 ft above NGVD 29

Well depth: 126 ft below land surface

Well: Ct-74

Aquifer: Red River alluvial aquifer

Altitude of land surface: 50 ft above NGVD 29

Well depth: 196 ft below land surface 

Well: Ct-347

Aquifer: Mississippi River alluvial aquifer

Altitude of land surface: 70 ft above NGVD 29

Well depth: 76 ft below land surface

Well: Co-50

Aquifer: Catahoula aquifer

Altitude of land surface: 55 ft above NGVD 29

Well depth: 700 ft below land surface

Figure 4. Water levels in well Ct-87 and 

Ct-347 screened in the Mississippi River 

alluvial aquifer, well Ct-74 screened in 

the Red River alluvial aquifer, and well 

Co-50 screened in the Catahoula aquifer 

in Catahoula and Concordia Parishes, 

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

Geological Survey, 2016). Land surface and 

water levels are in feet (ft) relative to the 

National Geodetic Vertical Datum of 1929 

(NGVD 29). Dashed lines indicate gaps in 

available data.

Catahoula Parish, including Larto Lake, Wallace Lake, Tew Lake, 

and Mean Lake (fig. 1). In 2010, 7.38 Mgal/d of surface water 

were withdrawn in Catahoula Parish from miscellaneous streams, 

including 7.34 Mgal/d for general irrigation and 0.04 Mgal/d for 

livestock (tables 1 and 2). 

Boeuf-Tensas Basin

The Boeuf River forms part of the north-central border 

of Catahoula Parish and flows into the Ouachita River on the 

northwestern side of Sicily Island. The Tensas River flows along 

the eastern border of Catahoula Parish until it empties into the 

Black River. 

Lower Ouachita Basin

The Ouachita River is the primary water body draining the 

Lower Ouachita Basin (fig. 1). The river flows into Catahoula 

Parish from Caldwell Parish; receives flow from tributaries 

including Bayou Louis, Gastis Creek, and many other small 

streams; and finally ends near Jonesville. The average daily 

discharge for the Ouachita River at Columbia Lock and Dam 

near Riverton (site number 07367630; fig. 1) during 1982–87 was 

about 21,326 cubic feet per second (ft3

/s) (U.S. Geological Survey, 

2016). 

Lower Red Basin

The Red, Black, and Little Rivers are primary drainages 

of the Lower Red Basin in Catahoula Parish. The Little River 

flows into Catahoula Parish from LaSalle Parish and ends near 

Jonesville as it merges with the Ouachita River and Tensas River 

to form the Black River (fig. 1). The Black River flows south, 

forming the eastern border of the parish until it flows into the Red 

River. The Red River forms the southern border of the parish. The 

average discharge of an upstream site, Red River at Alexandria 

(site number 07355500), was 30,770 ft3

/s during 1928–82 

(Carlson and others, 1983). 

Surface-Water Quality 

Samples taken from the Ouachita River at Columbia during 

1974–93, Red River at Lock and Dam No. 1 near Vick during 

1983–95, and Black River at Jonesville during 1958–72 were 

found to have median values for hardness that ranged from soft 

to hard and median pH values of 6.7–7.6 standard units (table 

4). Chloride and sulfate concentrations generally did not exceed 

SMCLs in samples from these rivers. Median dissolved-oxygen 

concentrations in the Ouachita River samples were 7.2 mg/L 

and in the Red River samples were 8.1 mg/L; a concentration of 

5 mg/L is considered the minimum value for a diverse population 

of fresh, warmwater biota, including sport fish (Louisiana 

Department of Environmental Quality, 2008). 

References Cited 

Carlson, D.D., Stallworth, G.R., Dantin, L.J., and Stuart, C.G., 1983, Water resources 

data Louisiana water year 1983: U.S. Geological Survey Water-Data Report 

LA–83–1.

Fendick, R.B., Jr., and Carter, Kayla, 2015, Potentiometric surface of the Catahoula 

aquifer in central Louisiana, 2013: U.S. Geological Survey Scientific Investigations 

Map 3339, 1 sheet, accessed April 5, 2016, at http://dx.doi.org/10.3133/sim3339.

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.

Lovelace, J.K., and Lovelace, W.M., 1995, Hydrogeologic unit nomenclature and 

computer codes for aquifers and confining units in Louisiana: Louisiana Department 

of Transportation and Development Water Resources Special Report no. 9, 12 p.

Martin, Angel, Jr., and Whiteman, C.D., Jr., 1986, Generalized potentiometric surface of 

the Catahoula aquifer in central Louisiana, 1980: U.S. Geological Survey WaterResources Investigations Report 86–4059, 1 sheet.
Table 3. Summary of selected freshwater-quality characteristics for the Mississippi River alluvial, Red River alluvial, and Catahoula 

aquifers in Catahoula Parish, Louisiana (U.S. Geological Survey, 2016).

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

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

less than]

Specific 

conductance, 

field 

(μS/cm at 

25 °C)

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, 

in μg/L

(as Fe)

Manganese, 

filtered, 

in μg/L

(as Mn) 

Dissolved 

solids, 

filtered

Mississippi River alluvial aquifer, 1941–2015 (47 wells)

Median 805 7.1 300 93 28.5 46 30 3.3 2,960 500 451

10th percentile 473.2 6.1 93.6 43.7 21.2 17 13 1.4 24.1 219.2 294.2

90th percentile 1,060 7.6 408.4 110 37.1 92.5 80.4 18 9,890 1,564 640.6

Number of 

samples 23 21 33 20 20 16 35 18 14 7 17

Percentage of 

samples that 

do not exceed 

SMCLs NA 76 NA NA NA NA 100 100 29 14 59

Red River alluvial aquifer, 1970–92 (48 wells) 

Median 886 6.9 320 87.5 28 65 35.5 1.2 5,500 595 531

10th percentile 686.8 6.6 170 61.4 20 22.8 19 <0.2 534 143 409.4

90th percentile 1,316 7.2 540 236 77.6 190 130 110 11,000 1,200 1,200

Number of 

samples 153 142 203 98 98 60 222 174 155 164 59

Percentage of 

samples that 

do not exceed 

SMCLs NA 98 NA NA NA NA 100 99 5 0 41

Catahoula aquifer, 1949–84 (47 wells)

Median 450 7.4 8.5 2.2 0.5 100 26 3.6 205 35 308

10th percentile 280 6.4 2 0.5 <0.1 52.6 14.0 0 20 <10 213.8

90th percentile 1,060 8 50 11.6 5.3 230 188 20.8 880 90 636

Number of 

samples 41 39 52 35 35 35 53 35 36 24 35

Percentage of 

samples that 

do not exceed 

SMCLs NA 87 NA NA NA NA 100 100 64 75 66

SMCLs

NA 6.5–8.5 NA NA NA NA 250 250 300 50 500

Martin, Angel, Jr.; Whiteman, C.D., Jr.; and Becnel, M.J., 1988, Generalized 

potentiometric surfaces of the upper and lower Jasper and equivalent aquifers in 

Louisiana, 1984: U.S. Geological Survey Water-Resources Investigations Report 

87–4139, 2 sheets. 

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

Transportation and Development Water Resources Special Report no. 17, 135 p.

Saucier, R.T., 1994, Geomorphology and Quaternary geologic history of the lower 

Mississippi Valley: Vicksburg, Miss., U.S. Army Corps of Engineers, v. 1-2, 364 p., 

28 pls. 

Seanor, R.C., and Smoot, C.W., 1995, Louisiana ground-water map no. 6—

Potentiometric surface, 1990, and water-level changes, 1974–90, of the Mississippi 

River alluvial aquifer in northeastern Louisiana: U.S. Geological Survey WaterResources Investigations Report 95–4146, 2 sheets.

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.

Smoot, C.W., 1989, Louisiana hydrologic atlas map no. 4—Geohydrologic sections 

of Louisiana: U.S. Geological Survey Water-Resources Investigations Report 

87–4288, 1 sheet, accessed February 10, 2012, at http://pubs.er.usgs.gov/

publication/wri874288.

Smoot, C.W., and Martin, Angel, Jr., 1991, Generalized potentiometric surfaces of the 

Red River alluvial aquifer, pool 1, Red River waterway area, central Louisiana: 

U.S. Geological Survey Water-Resources Investigations Report 91–4109, 7 sheets.

Snider, J.L., and Sanford, T.H., Jr., 1981, Water resources of the terrace aquifers, 

central Louisiana: Louisiana Department of Transportation and Development, 

Office of Public Works Water Resources Technical Report no. 25, 48 p.
Table 4. Summary of selected water-quality characteristics for the Ouachita, Black, and Red Rivers near Catahoula Parish, Louisiana 

(U.S. Geological Survey, 2016).

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

microgram 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, 

in μg/L

(as Fe)

Ouachita River at Columbia (1974–93)1

Median 168 7.2 6.7 31 8.4 2.1 19 29 13 280

10th percentile 88 4.7 6.1 19 5 1.3 8.3 13 6.8 110

90th percentile 324 10.3 7.2 48 14 3.1 40 61 23 550

Number of samples 154 148 155 154 154 154 153 153 151 73

Percentage of 

samples that 

do not exceed 

SMCLs

NA NA 66 NA NA NA NA 100 100 62

Red River at Lock and Dam No.1 near Vick (1983–95)2

 

Median 492 8.1 7.6 130 36.5 9.8 41 62 50 NA

10th percentile 213.2 6 7.1 66.3 19.1 3.9 15 20 20 NA

90th percentile 1,039 10.6 8.0 269.4 69.9 23 100 140 120 NA

Number of samples 123 121 123 122 122 122 110 120 119 NA

Percentage of 

samples that 

do not exceed 

SMCLs

NA NA 100 NA NA NA NA 99 100 NA

Black River at Jonesville (1958–72)3

Median 402 NA 6.9 63 17 4.6 49.5 81 10 NA

10th percentile 155.5 NA 6.4 30.4 9.0 1.8 16 27.6 6.2 NA

90th percentile 763 NA 7.4 110 30 8.5 101.9 190 16 NA

Number of samples 536 NA 528 535 516 512 512 537 521 NA

Percentage of 

samples that 

do not exceed 

SMCLs

NA NA 86 NA NA NA NA 94 100 NA

SMCLs

NA NA 6.5–8.5 NA NA NA NA 250 250 300

1

Site number 07367640 (see fig. 1).

2

Site numbers 07355603 and 073556005 (see fig. 1).

3

Site number 07373267 (see fig. 1).

U.S. Environmental Protection Agency, 2016, Secondary Drinking Water Standards: 

Guidance for Nuisance Chemicals, accessed April 13, 2016, at https://www.

epa.gov/dwstandardsregulations/secondary-drinking-water-standards-guidancenuisance-chemicals.

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U.S. Geological Survey Web page, accessed September 28, 2016, at http://dx.doi.

org/10.5066/F7P55KJN.

Whitfield, M.S., Jr., 1975, Geohydrology and water quality of the Mississippi 

River alluvial aquifer, northeastern Louisiana: Louisiana Department of Public 

Works Water Resources Technical Report no. 10, 29 p.

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

Survey in cooperation with the Louisiana Department 

of Transportation and Development. 

By Vincent E. White

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) https://doi.org/10.3133/fs20163101