U.S. Department of the Interior

U.S. Geological Survey

Fact Sheet 2014–3118

February 2015

Prepared in cooperation with the Louisiana Department of Transportation and Development 

Water Resources of St. Charles Parish, Louisiana

Introduction 

Information concerning the availability, use, and quality 

of water in St. Charles 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 (http://waterdata.

usgs.gov/nwis) are the primary sources of the information 

presented here. 

In 2010, about 2,476 million gallons per day (Mgal/d) of 

water were withdrawn in St. Charles Parish, Louisiana, including 

about 2,471 Mgal/d from surface-water sources and about 

4.24 Mgal/d from groundwater sources1

 (table 1). Withdrawals 

for power generation accounted for about 79 percent of the total 

water withdrawn (table 2).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

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

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

water withdrawals in the parish generally increased from 1960 to 

2005 but decreased by about 20 percent from 2005 to 2010 (fig. 

2). Most of the decrease resulted from reduced surface-water 

withdrawals for industrial uses (U.S. Geological Survey, 2014a).

1

Water-withdrawal data are based on reported site-specific 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. 

310

§ ̈10

§ ̈55

30°10'

30°00'

29°50'

91°30' 91°20' 91°10'

North American Datum of 1983

Albers Equal-Area Conic projection

Base modified from U.S. Geological Survey digital data

Lac des

Allemands

Lake 

Cataouatche

Lake

Salvador

Lake Pontchartrain

Bayou des

Allemands

Mississippi River GULF OF MEXICO

Hahnville

Luling

Norco

Laplace

Des Allemands

07374400

SC-9

SC-14

Davis Pond

Diversion

Structure

O

0 5

0 5

10 MILES

10 KILOMETERS

TEXAS ARKANSAS MISSISSIPPI

LOUISIANA

ST CHARLES

PARISH 07373291C 07374000 C

SC-14

EXPLANATION

Approximate areas where fresh 

 groundwater is available, by aquifer

 Gramercy aquifer—Boundary dashed and

 queried where uncertain (modified from

 Tomaszewski, 2003, and Hosman, 1972)

 Norco aquifer (modified from

 Tomaszewski, 2003)

 Gonzales-New Orleans aquifer (modified

 from Tomaszewski, 2003)

Approximate area of point-bar deposits—

 May contain freshwater (modified

 from Tomaszewski, 2003)

Line of section (see fig. 3)

Well for which hydrograph is shown

 and number (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 3)

A'A

07374400

07373291

C

O

LAFOURCHE

PARISH

ST JOHN THE BAPTIST

PARISH

JEFFERSON

PARISH

ST CHARLES PARISH

BONNET CARRE SPILLWAY

A'

A

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

in St. Charles Parish, Louisiana, 2010 (Sargent, 2011; Sargent, 

unpub. data, 2011).

[<, less than]

Aquifer or surface-water body Groundwater Surface water

Point-bar deposits <0.01

Gramercy aquifer 0.02

Norco aquifer 0.48

Gonzales-New Orleans aquifer 3.74

Mississippi River 2,471.23

Miscellaneous streams 0.05

Total 4.24 2,471.28

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

category in St. Charles Parish, Louisiana, 2010 (modified from 

Sargent, 2011).

Use category Groundwater Surface water Total

Public supply 0.00 8.50 8.50

Industrial 4.21 503.20 507.41

Power generation 0.00 1,959.53 1,959.53

Rural domestic 0.02 0.00 0.02

Livestock 0.01 0.05 0.05

Total 4.24 2,471.28 2,475.51

0

500

1,000

1,500

2,000

2,500

3,000

3,500

1960 1965 1970 1975 1980 1985 1990 1995 2000 2005 2010

Year

Annual withdrawals, in million gallons per day

Groundwater

Surface water

EXPLANATION

1960–2010 (Sargent, 2011).

Figure 2. Water withdrawals in St. Charles Parish, Louisiana, 

Groundwater Resources

The primary aquifers that contain freshwater (water with a 

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

in St. Charles Parish, from shallowest to deepest, include the 

Gramercy aquifer, Norco aquifer, and the Gonzales-New Orleans 

aquifer (fig. 3). 

Mississippi River point-bar deposits also contain limited 

supplies of freshwater; however, the water is generally high in 

iron content and very hard,2 with little reported pumpage (less 

than 0.01 Mgal/d in 2010; table 1). Deeper aquifers in St. Charles 

Parish contain only saltwater (water with chloride concentrations 

greater than 250 mg/L). In 2010, groundwater withdrawals for 

various uses included industrial, rural domestic, and livestock 

(table 2; Louisiana Department of Natural Resources, 2011). 

In general, the base of fresh groundwater in St. Charles 

Parish ranges from about 350 feet (ft) below the National 

Geodetic Vertical Datum of 1929 (NGVD 29) near the town of 

Des Allemands to over 700 ft below NGVD 29 in an area about 

2 miles (mi) south of the Lake Pontchartrain shoreline. Little 

or no fresh groundwater is available in the southern half of St. 

Charles Parish (fig. 1; Hosman, 1972; Tomaszewski, 2003). 

Recharge to aquifers is from downward percolating rainfall in 

areas north of the parish where the aquifers are at or near land 

surface, from upward and downward vertical leakage from other 

aquifers through confining layers or in areas where aquifers are 

directly connected, and from the Mississippi River via pointbar deposits (Hosman, 1972). Discharge from the aquifers is 

generally by upward and downward vertical leakage through 

confining layers into adjacent aquifers, flow into rivers and lakes, 

and withdrawals from wells. 

Gramercy Aquifer 

The Gramercy aquifer contains freshwater in western St. 

Charles Parish and in a localized area near Norco and Hahnville 

(fig. 1; Tomaszewski, 2003). The aquifer is composed of fine to 

coarse sand and is the least continuous of the three major aquifers 

underlying St. Charles Parish (Hosman, 1972). The aquifer is 

thin or missing in northern St. Charles Parish along the Lake 

Pontchartrain shoreline (Tomaszewski, 2003). North of a line 

between the southeastern tip of Lac des Allemands and Lake 

Cataouatche, structural contour data indicated that the altitude of 

the top of the Gramercy aquifer, although variable, is generally 

between 100 and 250 ft below NGVD 29 (Hosman, 1972; 

Tomaszewski, 2003). Where the aquifer is present, thickness 

ranges from less than 100 to 150 ft or more (fig. 3; Tomaszewski, 

2003). The Gramercy aquifer is in contact with and hydraulically 

connected to a point-bar deposit of the Mississippi River in 

the vicinity of Hahnville (fig. 3). Water levels in the Gramercy 

aquifer fluctuate seasonally, reaching highs in the spring 

and lows in the fall, corresponding to Mississippi River 

levels (Hosman, 1972). 

State well-registration records listed 27 active water wells 

screened in the Gramercy aquifer in St. Charles Parish in 2014, 

including 12 domestic, 9 irrigation, 3 industrial, and 3 public 

supply. Well depths ranged from 60 to 357 ft below land surface. 

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).
EXPLANATION

Freshwater in sand

Saltwater in sand—Saltwater 

 contains greater than 250 milligrams 

 per liter chloride

Mostly clay

Bend in section

ST. JOHN THE 

BAPTIST PARISH

ST. CHARLES 

PARISH

Mississippi

River

Mississippi

River Laplace

Point bar Point bar

Gramercy aquifer

Norco aquifer

Gonzales-New Orleans aquifer

Mississippi

River

Vertical datum is National Geodetic Vertical Datum of 1929 (NGVD 29)

Possible

connection

↑

Point bar

WEST

A

NGVD 29

-500

-1,000

FEET

NGVD 29

-500

-1,000

FEET

EAST

A’

VERTICAL SCALE GREATLY EXAGGERATED

0 5 MILES

0 5 KILOMETERS

Figure 3. West-to-east hydrogeologic section through St. Charles Parish, Louisiana (modified from Hosman, 1972). Trace of section shown 

on figure 1.

Reported yields from wells screened in the Gramercy aquifer in 

St. Charles Parish have ranged from 25 to 500 gallons per minute 

(gal/min) (Louisiana Department of Natural Resources, 2014). In 

2010, groundwater withdrawals from the Gramercy aquifer in St. 

Charles Parish totaled about 0.02 Mgal/d. 

The quality of freshwater in the Gramercy aquifer varies 

widely in response to vertical leakage from adjacent aquifers. 

Where the quality is not affected by vertical flow from other 

aquifers, the water is generally a mixed calcium and magnesiumbicarbonate, sodium-chloride type and is very hard. Downdip, 

the water becomes a sodium-chloride type (Hosman, 1972). 

Norco Aquifer 

The Norco aquifer contains freshwater in northwestern St. 

Charles Parish. North of a line between the southeastern tip of 

Lac des Allemands and Lake Cataouatche, structural contour 

data indicated that the altitude of the top of the Norco aquifer, 

although variable, is generally between 250 and 400 ft below 

NGVD 29 in St. Charles Parish (Hosman, 1972; Tomaszewski, 

2003). The aquifer thickness ranges from about 25 ft to about 

275 ft in the parish. The aquifer contains fine to coarse sand but 

is mostly medium to coarse sand and is well sorted in the vicinity 

of the Mississippi River and possibly elsewhere (Hosman, 1972). 

Water levels rose in the Norco aquifer in the Norco 

area from the 1950s to the mid-1990s in response to reduced 

groundwater withdrawals. Water levels in the Norco aquifer at 

well SC-14, located north of the Mississippi River near Norco 

(fig. 1), rose about 60 ft from 1958 to 1995 (fig. 4). 

State well-registration records listed 26 active wells screened 

in the Norco aquifer in St. Charles Parish in 2014, including 14 

industrial, 8 irrigation, and 4 domestic. Well depths ranged from 

about 320 to 460 ft below land surface. Reported yields from wells 

screened in the Norco aquifer in St. Charles Parish have ranged 

from 175 to 2,000 gal/min (Louisiana Department of Natural 

Resources, 2014). In 2010, groundwater withdrawals from the 

Norco aquifer in St. Charles Parish totaled about 0.48 Mgal/d, 

entirely for industrial use, except for a less than 0.01-Mgal/d split 

between rural domestic and livestock use. 

Water in the Norco aquifer ranges from a sodium-bicarbonate 

type to a sodium-chloride type. Where groundwater is fresh, 

hardness ranges from 40 to 60 mg/L as calcium carbonate; 

hardness increases with salinity to more than 500 mg/L. Iron 

concentration is generally less than 500 micrograms per liter. 

Dissolved solids concentration ranges from about 750 to 

1,000 mg/L where the water is fresh to more than 2,500 mg/L 

where the water is salty. Color of the water in the aquifer ranges 

from 5 to 180 platinum cobalt units (PCU). At Norco, water color 

ranges from 50 to 100 PCU in the Norco aquifer. These values 

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

Maximum Contaminant Levels3

 (SMCLs) for color of 15 PCU 

(Hosman, 1972). 

3

The SMCLs are nonenforceable Federal guidelines regarding cosmetic effects 

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

color) of drinking water. At high concentrations or values, health implications 

as well as aesthetic degradation may be present. SMCLs were established as 

guidelines for the States by the U.S. Environmental Protection Agency (1992). 
-90

-80

-70

-60

-50

-40

-30

-20

-10

0

1948 1952 1956 1960 1964 1968 1972 1976 1980 1984 1988 1992 1996

Altitude of water level, in feet (ft)

Year

Well: SC-9

Aquifer: Gonzales-New Orleans

Well depth: 808 ft below land surface

Altitude of land surface: 4.79 ft above NGVD 29

Well: SC-14

Aquifer: Norco

Well depth: 404 ft below land surface

Altitude of land surface: 5.51 ft above NGVD 29

Figure 4. Water levels in well SC-9 screened in the Gonzales-New Orleans aquifer and well SC-14 screened in the Norco aquifer in St. 

Charles Parish, Louisiana (see fig. 1 for well locations; U.S. Geological Survey, 2012a). Altitude of land surface and water level is measured in 

feet (ft) relative to the National Geodetic Vertical Datum of 1929 (NGVD 29).

Gonzales-New Orleans Aquifer 

The Gonzales-New Orleans aquifer generally contains 

saltwater in the southern half of St. Charles Parish and 

freshwater underlain with saltwater in the northern half 

(Tomaszewski, 2003). North of a line between the southeastern 

tip of Lac des Allemands and Lake Cataouatche, structural 

contour data indicated that the altitude of the top of the 

Gonzales-New Orleans aquifer, although variable, is generally 

between 450 ft below NGVD 29 near Lake Pontchartrain and 

over 800 ft below NGVD 29 near Lake Cataouatche (Hosman, 

1972; Tomaszewski, 2003). Aquifer thickness ranges from about 

175 to about 325 ft (Hosman, 1972) and contains fine to very 

fine sand (Hosman, 1972). The aquifer has a general regional dip 

of 25 to 50 ft per mile to the south. 

Water levels in the Gonzales-New Orleans aquifer in 

the Norco area initially declined in the early 1950s because 

of groundwater withdrawals (Eddards and others, 1956). 

Water levels in the aquifer at well SC-9, located north of the 

Mississippi River near Norco (fig. 1), were stable from 1972 

to 1982, except for brief fluctuations, and were at about 20 

ft below NGVD 29 when data collection at the well ended in 

1995 (fig. 4). 

State well-registration data listed 3 active wells screened in 

the Gonzales-New Orleans aquifer in St. Charles Parish in 2014, 

including 1 industrial, 1 irrigation, and 1 domestic. Well depths 

ranged from 670 to 754 ft below land surface. One of these wells 

had reported a yield of 1,293 gal/min (Louisiana Department 

of Natural Resources, 2014). In 2010, reported groundwater 

withdrawals from the Gonzales-New Orleans aquifer in St. 

Charles Parish totaled about 3.74 Mgal/d, entirely for industrial 

use, except for less than 0.002 Mgal/d for domestic use. 

Groundwater in the Gonzales-New Orleans aquifer ranges 

from a mixed sodium-bicarbonate-chloride type in freshwater 

areas to a sodium-chloride type in saltwater areas. Freshwater 

in the aquifer is soft. As mineralization increases downdip and 

vertically downward, the water changes to a sodium-chloride 

type and becomes harder (Hosman, 1972). Freshwater hardness 

ranges from about 10 to 40 mg/L as calcium carbonate, whereas 

saltwater hardness increases to more than 300 mg/L. Color is 

generally above the SMCL of 15 PCU (Hosman, 1972). 

Surface-Water Resources 

The Mississippi River is the primary source of fresh surface 

water in St. Charles Parish (table 1). In 2010, about 2,470 

Mgal/d of surface water were withdrawn in the parish, including 

about 503 Mgal/d for industrial use and 1,960 Mgal/d for power 

generation. Other use categories included public supply and 

livestock (table 2). Almost all the surface-water withdrawals 

came from the Mississippi River. Most surface water withdrawn 

for power generation and industrial purposes was used for 

cooling and was returned to its source after use (Sargent, 2011). 

Other major surface-water bodies bordering the parish include 

Lake Pontchartrain, Lake Cataouatche, Lake Salvador, Lac des 

Allemands, and Bayou des Allemands (fig. 1); however, there 

were no reported withdrawals from these water bodies in 2010. 
Mississippi River

The Mississippi River drains more than 40 percent of 

the continental United States. Water quality and quantity in 

the Mississippi River are affected by both natural processes 

and human activities in the Mississippi River Basin upstream 

of St. Charles Parish. These processes and activities include 

precipitation, erosion, and the effects of dams and diversions. 

Water quality is also affected by runoff, discharge, and 

contamination from agricultural, municipal, and industrial 

activities. Water quantity and quality both vary seasonally 

because of the rate and distribution of precipitation and landuse patterns. Water-quality constituents such as agricultural 

pesticides and nutrients are generally highest in June and 

July, representing the “spring flush,” which results from 

the runoff of upstream applications of these pesticides and 

nutrients (Demcheck and others, 2004). Suspended sediment 

concentrations are generally highest in late winter and early 

spring and lowest in late summer and fall (Wells, 1980). Water 

quantity can vary appreciably, as indicated by record discharges 

at the Mississippi River at Baton Rouge, Louisiana (fig. 1; site 

number 07374000), of 1,436,000 cubic feet per second (ft3/s) in 

May 2011 and 132,800 ft3/s in October 2012 (U.S. Geological 

Survey, 2014b). 

The average flow of the Mississippi River near Red River 

Landing, Louisiana (site number 07373291; fig. 1, index map), 

located about 175 river miles upstream of Norco, was about 

460,000 ft3/s (about 298,000 Mgal/d) during 1928–76 (Wells, 

1980). The flow in the Mississippi River at Red River Landing is 

representative of flows in St. Charles Parish because there are no 

major tributaries or distributaries, and the river is mostly leveed 

between the landing and the parish boundary. 

Water samples collected and analyzed during 1957–99 

indicated that water in the Mississippi River at Luling (fig. 1; 

site number 07374400) is generally hard (table 3) and usually 

does not exceed the SMCLs for pH and concentrations of 

chloride, sulfate, and iron. Dissolved oxygen concentration is 

generally greater than 5 mg/L, which is considered the minimum 

value for a diversified population of fresh, warmwater biota, 

including sport fish (Louisiana Department of Environmental 

Quality, 2008). 

Two diversion structures, the Bonnet Carre Spillway and 

the Davis Pond Freshwater Diversion Structure, are located on 

the Mississippi River in St. Charles Parish (fig. 1). The Bonnet 

Carre Spillway, located on the north bank of the river between 

Laplace and Norco, includes a 7,000-ft-wide flood control 

structure capable of diverting up to 250,000 ft3/s of Mississippi 

River water through a 5.7-mile-long, 8,000-acre spillway into 

Lake Pontchartrain (U.S. Army Corps of Engineers, 2009). 

The Davis Pond Freshwater Diversion Structure, located on the 

south bank of the river about 2 mi east of Luling (fig. 1), uses a 

combination of culverts and pumps to divert freshwater (at rates 

up to 10,650 ft3/s), nutrients, and sediment from the Mississippi 

River into nearby wetlands to mitigate land loss, enhance 

vegetation, and improve fish and wildlife habitat (U.S. Army 

Corps of Engineers, 2000). 

Lakes

Lake Pontchartrain (partially shown on fig. 1) has a surface 

area of 621 square miles (mi2) and an average depth of about 11 

ft. There are appreciable spatial variations in salinity because 

Lake Pontchartrain is connected to the Gulf of Mexico. The 

northwestern and western areas of the lake may be fresh during 

Table 3. Summary of selected water-quality characteristics for the Mississippi River in St. Charles Parish, Louisiana, 1957–99 (U.S. 

Geological Survey, 2012b). 

[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; <, less than; SMCL, Secondary Maximum Contaminant Level established by the U.S. Environmental Protection Agency (2012); 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)

Mississippi River at Luling1

Median 398 8.2 7.6 150 40 11 21 24 50 <20

10th percentile 298 6.2 7.2 110 32 7.9 12 16 36 <10

90th percentile 500 11.2 7.9 180 48 15 34 36 71 60

Number of samples 665 328 656 659 634 636 365 662 662 294

Percent of samples 

that do not exceed 

SMCLs

NA NA 99.8 NA NA NA NA 100 100 98.6

SMCLs

NA NA 6.5–8.5 NA NA NA NA 250 250 300

1

Station number 07374400.
some parts of the year (Shampine, 1971). Lac des Allemands has 

a surface area of about 23 mi2

 and an average depth of about 5 ft. 

Water quality in the lake varies spatially and seasonally. Chloride 

concentrations are moderately high and will occasionally exceed 

the SMCL of 250 mg/L (Shampine, 1971). 

References Cited

Demcheck, D.K.; Tollett, R.W.; Mize, S.V.; Skrobialowski, 

S.C.; Fendick, R.B., Jr.; Swarzenski, C.M.; and Porter, 

Stephen, 2004, Water quality in the Acadian-Pontchartrain 

Drainages, Louisiana and Mississippi, 1999–2001: U.S. 

Geological Survey Circular 1232, 41 p.

Eddards, M.L., Kister, L.R., and Scarcia, Glenn, 1956, 

Water resources of the New Orleans area, Louisiana: U.S. 

Geological Survey Circular 374, 41 p.

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.

Hosman, R.L., 1972, Ground-water resources of the Norco 

area, Louisiana: Department of Conservation, Louisiana 

Geological Survey, and Louisiana Department of Public 

Works Water Resources Bulletin no. 18, 61 p. 

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, 2014, Strategic 

Online Natural Resources Information System (SONRIS): 

Louisiana Department of Natural Resources database, 

accessed November 7, 2014, at http://sonris.com/.

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

Department of Transportation and Development Water 

Resources Special Report no. 17, 135 p. 

Shampine, W.J., 1971, Chemical, biological, and physical data 

for the major lakes and reservoirs in Louisiana: Louisiana 

Department of Public Works Basic Records Report no. 5, 98 

p.

Tomaszewski, D.J., 2003, Groundwater resources along the 

lower Mississippi River, southeastern Louisiana: Louisiana 

Department of Transportation and Development Water 

Resources Technical Report no. 69, 23 p. 

U.S. Army Corps of Engineers, 2000, New Orleans district: 

Davis Pond Freshwater Diversion Project, accessed 

November 25, 2013, at http://www.mvn.usace.army.mil/

Portals/56/docs/PAO/Brochures/DavisPondBrochure.PDF. 

U.S. Army Corps of Engineers, 2009, New Orleans district: 

Mississippi River Flood Control, Bonnet Carré Spillway 

Overview, accessed November 22, 2013, at http://www.mvn.

usace.army.mil/Missions/MississippiRiverFloodControl/

BonnetCarreSpillwayOverview.aspx.

U.S. Environmental Protection Agency, 1992, Secondary 

drinking water regulations—Guidance for nuisance 

chemicals: U.S. Environmental Protection Agency 

publication EPA 810/K-92-001, 4 p., accessed September 

28, 2011, at http://water.epa.gov/drink/contaminants/

secondarystandards.cfm. 

U.S. Environmental Protection Agency, 2012, 2012 Edition 

of the drinking water standards and health advisories: U.S. 

Environmental Protection Agency publication EPA 822-S12-001, Office of Water, 12 p., accessed August 7, 2012, 

at http://water.epa.gov/action/advisories/drinking/upload/

dwstandards2012.pdf.

U.S. Geological Survey, 2012a, Groundwater levels for 

Louisiana: National Water Information System Web Interface: 

Accessed July 13, 2012, at http://nwis.waterdata.usgs.gov/la/

nwis/gwlevel. 

U.S. Geological Survey, 2012b, Water quality samples for 

Louisiana [data for USGS 07374400 Mississippi R @ Luling, 

LA]: National Water Information System Web Interface, 

accessed August 20, 2012, at http://nwis.waterdata.usgs.gov/

la/nwis/qwdata/?site_no=07374400.

U.S. Geological Survey, 2014a, U.S. Geological Survey Water 

Resources Cooperative Program: Louisiana Water Use 

Program 1960–2010 Data, accessed October 14, 2014, at 

http://la.water.usgs.gov/WaterUse/default.asp.

U.S. Geological Survey, 2014b, Water-resources data for the 

United States, water year 2013: U.S. Geological Survey 

Water-Data Report WDR-US-2013, site 07374000, accessed 

August 19, 2014, at http://wdr.water.usgs.gov/wy2013/

pdfs/07374000.2013.pdf. 

Wells, F.C., 1980, Hydrology and water quality of the lower 

Mississippi River: Louisiana Department of Transportation 

and Development, Office of Public Works Water Resources 

Technical Report no. 21, 83 p. 

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, 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/fs20143118