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A. MR&T SYSTEM INFORMATION

1. General MR&T Information. The MR&T Project is the largest FRMS in the world. It protects the 

36,000-square-mile Lower Mississippi River Valley (LMRV) from periodic overflows of the Mississippi River. 

Figure II-1 shows the major river systems that comprise the Mississippi River drainage basin. The MR&T 

System is designed to convey the project design flood (PDF), represented by the maximum event that had a 

reasonable probability of occurring from a meteorological viewpoint. 

Figure II-1. Major River Systems within the Mississippi River Basin

The MR&T System includes an extensive levee system; floodways to divert excess flows past critical reaches; 

channel improvement and stabilization features to protect the integrity of flood risk management measures and 

to ensure proper alignment and depth of the navigation channel; and a system of reservoirs to regulate flows and

backwater areas to provide storage during extreme events. Additionally, there are tributary basin improvements 

including levees, headwater reservoirs, and pumping stations that expand FRM coverage and improve drainage 

into adjacent areas within the alluvial valley. The main stem levee system begins at the head of the alluvial 

valley at Cape Girardeau, MO, and continues to Venice, LA, near the Gulf of Mexico on the right descending 

bank and to Bohemia, LA on the left descending bank. Figure II-2 identifies and provides the general locations 

of the primary MR&T System components. The MR&T levee system includes 3,787 miles of authorized 

embankments and floodwalls. Of this, nearly 2,216 miles are along the main stem Mississippi River, and the 

remaining levees are backwater, tributary, and floodway levees. 
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Figure II-2. General Locations of Primary Mississippi & Tributaries System Components
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2. Physical Infrastructure and Operational Strategy. MR&T FRMS components consist of 

completed and uncompleted structures and improvements. The individual structures are operated as a 

system in accordance with the MR&T Flood Control Plan, to reduce overall flood risks throughout the 

LMRV. The design and operational strategy for the MR&T System does not attempt to entirely exclude the 

river from its natural floodplain. Instead, it accommodates the natural tendency of the river during 

extraordinary floods by incorporating floodway and backwater features that are not utilized during small and 

more frequent flood events.

Levees are the backbone of the MR&T Flood Control Plan. They protect the vast expanse of the 

developed alluvial valley from periodic overflows of the Mississippi River. The grade and section of 

the present levee system dwarf those of the system that was overwhelmed during the 1927 flood (figure II3.) In addition to higher and wider levees, the MR&T levee designs incorporate technological advancements 

that account for the type, condition, and moisture content of material used in the construction of the levees. 

The design levee grades provide for freeboard – the distance between the PDF flow line and the top of the 

levee. The presently approved freeboard is 3 feet on the Mississippi River levees below Cairo, IL, to the Old 

River Control Complex (ORCC), 3 to 5 feet from the ORCC to Venice, LA, 3 feet on the Bonnet Carre 

guide levees and no freeboard to 2 feet of freeboard on the Atchafalaya Basin Floodway System levees.

Levee grades between Cape Girardeau and Cairo and along the south banks of the Arkansas and Red rivers 

provide for a three-foot minimum freeboard over the maximum tributary flood meeting the maximum flood 

of record on the Mississippi River, with provisions to ensure that the same flood meeting the PDF will not 

overtop the levee. 

Figure II-3. Evolution of Mississippi River Levees (1844-Present)

The integrity of the levee system is also bolstered by advancements in the design, construction, 

installation and maintenance of seepage control measures, to include landside berms, drainage 

trenches, drainage blankets, and relief wells. Additionally, more than 1,000 miles of articulated 

concrete mattress revetment, over 300 miles of dikes and numerous hard points, chevrons and bendway 
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weirs associated with channel improvement efforts maintain a stable channel protecting the levees from 

erosion and assuring the reliability of the navigation channel. 

At critical stages or flow rates, other features are activated to control and convey floodwaters and 

relieve stress on the levees. The first key feature is in the vicinity of Cairo, IL. When the river 

reaches critical stages on the Cairo gage, the BPNM floodway is operated to divert up to about 

550,000 cfs and prevent flood stages from exceeding the design elevation of the levees and floodways 

at and near Cairo, IL, the levees along the west bank above Birds Point, and the east bank levee 

adjacent to the floodway. 

There are two major reservoirs—Kentucky and Barkley Lakes— on the Tennessee and Cumberland 

rivers that are not features of the MR&T project, but are authorized to reduce flood stages on the 

Mississippi River in the vicinity of and downriver from Cairo. Because of the close proximity of the 

reservoirs to the confluence of the Mississippi and Ohio rivers, regulation of the reservoirs has a 

predictable influence on the operation of the BPNM floodway. The 1944 FCA directs the Tennessee 

Valley Authority (TVA) to regulate the release of water from the Tennessee River into the Ohio River

in accordance with instructions from the Corps. Objectives developed by the Great Lakes and Ohio 

River Division (LRD) for the Kentucky-Barkley reservoir outflows have priorities to safeguard the 

Mississippi River levee system, to reduce the frequency of use of the BPNM floodway and to reduce 

the frequency and magnitude of flooding of lands along the lower Ohio and Mississippi rivers which 

are unprotected by levees. When floods threaten the flood control features along the upper reaches of 

the MR&T project, the MRC president and the LRD commander—a position that also serves as a 

member of the Mississippi River Commission—work together to regulate releases from Barkley and 

Kentucky lakes with the concurrence of the general manager of the TVA to accomplish these 

objectives.

Between the lower end of the BPNM floodway and the Red River, a combination of flood control 

reservoirs, backwater areas and a comprehensive channel improvement and rectification programs

supplement the levee system in passing floods. Backwater areas are located at the mouths of the St. 

Francis, White, Yazoo, and Red Rivers. Significant portions of the upper sections of these backwater 

areas receive protection from overflows of the Mississippi River afforded by the mainline levees. The 

lower portions of these areas serve as natural storage during larger floods. The backwater levees are 

designed to naturally overtop when flood stages along the main stem of the Mississippi River reach 

specified levels. When flood stages subside, floodwaters within the backwater areas drain through 

floodgates or is pumped. The channel rectification program improves the carrying capacity of the 

main channel and lowers the flood flow line through the use of cutoffs (severing large bends from the 

river) and corrective dredging.

From the Red River backwater to the Gulf of Mexico, the MR&T flood control plan uses a more 

elaborate system to manipulate flood waters. The first key component of that reach is the ORCC. 

Construction of the ORCC began in 1954 to prevent the Atchafalaya from capturing the Mississippi 

River. The complex is designed to maintain the 1950 latitude flow distribution between the 

Mississippi River and the Atchafalaya/Red River System of 70 percent to 30 percent, respectively. 

Approximately 30 miles downstream from the ORCC, the Morganza Floodway provides for additional 

diversion of floodwaters. Governed by a 3,900-foot long and a 125-bay intake structure, the floodway 

can divert up to 600,000 cfs from the Mississippi River to the Atchafalaya basin when the Mississippi 

River flows below Red River Landing are projected to exceed 1,500,000 cfs. 
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The West Atchafalaya floodway extends along the west side of the Atchafalaya River Basin. The floodway 

contains an eight-mile long fuseplug section of levee at its head. When the fuseplug section crevasses or 

when the west bank Atchafalaya River levee overtops, the floodway can divert up to 250,000 cfs. Under the 

present water control plan, the West Atchafalaya Floodway would be the last feature of the flood control 

system to be used. The Atchafalaya River, the Morganza floodway, and the West Atchafalaya floodway 

converge at the lower end of the Atchafalaya River levees to form the Atchafalaya basin floodway. This 

floodway receives flow from the Red River and from the Mississippi River via the ORCC and the Morganza 

Floodway; it is designed to carry 1,500,000 cfs, the combined flow of the West Atchafalaya Floodway, 

Atchafalaya River, and Morganza Floodway. The Atchafalaya Basin Floodway has two outlets, Lower 

Atchafalaya River, with a project flood flow of 919,000 cfs, and Wax Lake Outlet, with a project flood flow 

of 581,000 cfs. The Avoca Island levee and Levees West of Berwick provide measures of risk reduction 

below Morgan City to communities such as Franklin, Calumet, and Patterson.

The MR&T Flood Control Plan provides additional control of the system below the Morganza 

floodway through the Bonnet Carré spillway, located approximately thirty miles above New Orleans, 

LA. The 7,200-foot long spillway structure is governed by 350 intake bays and connects to a six-mile 

long floodway that empties into Lake Pontchartrain. The floodway is designed to divert up to 250,000 

cfs from the Mississippi River, to ensure the peak discharge flow at New Orleans does not exceed 

1,250,000 cfs.

3. MR&T Project Design Flood. The PDF used for the original design of the MR&T Project, 

following the 1928 FCA authorization, was a combination of separate analyses conducted by the US 

Weather Bureau (now the National Weather Service) and the MRC. The discharges and flood stages 

developed by the agencies were very similar, but because the Weather Bureau analyzed the “maximum 

possible” flood in comparison to the Commission’s analysis of the “maximum probable” flood, differences 

in the estimates emerged. Where such differences did occur, the higher stage was used in putting together 

the final PDF design. 

The PDF has been re-evaluated and/or revised several times. Development of the current PDF began in 

1954, when the Senate Committee on Public Works requested another thorough examination of all 

components of the MR&T Project. Pursuant to that request, the MRC and the Weather Bureau again 

conducted a cooperative study. This study incorporated previously unavailable data regarding the sequence, 

severity and distribution of past major storms and investigated 35 different hypothetical combinations of 

actual storms that produced significant amounts of precipitation and runoff. The Weather Bureau arranged 

the historical storms sequentially to mimic frontal movements and atmospheric situations that were 

consistent with those occurring naturally to determine the most feasible pattern capable of producing the 

greatest amount of runoff on the LMR. This included the consideration of storm transpositions, storm 

intensity adjustments, seasonal variations, and storm mechanics. In simpler terms, the Weather Bureau 

developed the project design storm series from various combinations of storms and resultant floods—

referred to as hypo floods— represented by the maximum event that had a reasonable probability of 

occurring from a meteorological viewpoint.

The studies revealed that Hypo-Flood 58A had the most probable chance of producing the greatest discharge 

on the LMR from Cairo to the Gulf of Mexico. Three severe storms comprised Hypo-Flood 58A. The first 

storm is the 1937 storm that struck the Ohio and LMR basins, with runoff increased by 10 percent. It is 

followed 3 days later by the 1950 storm over the same general area. This storm is followed 3 days later by 

the 1938 storm, with its center transposed 90 miles to the north and the rainfall pattern rotated by 20 degrees 

to maximize its coverage over all the tributary basins on the lower Mississippi River.
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To convert Hypo-Flood 58A into the PDF, the MRC developed the flood flows that would occur from the 

three storms and routed them through the tributary systems under three conditions: unregulated by 

reservoirs; regulated by reservoirs that existed in 1950; and regulated by the reservoirs that existed at that 

time, plus those proposed to be constructed in the near future (1960 timeframe). The flood flows were then 

routed down the Mississippi River to determine the peak discharges at key locations. The MRC selected the 

58A flood with near future reservoirs condition, referred to as 58A-EN (existing or near completion), as the 

basis for the PDF flowline and adopted it as the PDF in 1956. See Appendix A for a list of the “future 

reservoirs”.

Following the 1973 flood, the MRC once again reviewed the adequacy of the PDF. The review concluded 

that the thorough approach used in 1955 was based on sound technology that remained reliable by current 

standards. The PDF discharges developed in 1955 have remained unchanged to present day except for the 

distribution of PDF flows through the lower Atchafalaya and Wax Lake outlets in the Atchafalaya Basin. 

The distribution of these two flows has changed over time as documented in the Atchafalaya Flowline 

Report in 2010. Figure II-4 provides a simplified illustration of the current PDF.

Figure II-4. Current Project Design Flood Diagram

B. MR&T BACKGROUND

1. Geology. The LMR lies within the Central Gulf Coastal Plain physiographic province. A 

northward extending lobe, the Mississippi Embayment of this province follows the axis of the 

Mississippi Basin and comprises the northern part of the LMRV (Schumm et al. 1982). Virtually all 

LMRV landforms and deposits are the result of fluvial, eolian, or marine processes. 
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The LMRV varies in width between 40 and 110 miles and includes parts of Missouri, Illinois, Tennessee, 

Kentucky, Arkansas, Mississippi, and Louisiana. The topography of the 53,000 square mile LMRV is 

characterized by a flat to slightly undulating surface underlain by alluvial and terrace deposits. Average 

floodplain elevations in the LMRV decline from about 325 feet mean sea level (msl) in extreme southern 

Illinois to about 40 feet msl at the northern edge of the deltaic plain. The average down valley slope is only 

0.6 feet/mile. Average relief in the upper part of the LMRV is about 25 feet and declines progressively 

southward. Uplands bordering the LMRV typically attain elevations of about 200 feet above those of the 

adjacent floodplain. Upland elevations also steadily decline southward. 

Soils in the LMRV range up to 300 feet in depth and consist mainly of sands and silt, grading progressively 

to very fine sands and silts in the lower portion of the area with extensive deposits of clay scattered through 

these formations. Typical of streams flowing through alluvial valleys, the LMR developed a highly sinuous 

course, creating numerous meander loops, bends, and oxbow lakes. Historically, the river shifted its channel 

frequently and reworked parts of its alluvial meander belt, thus contributing to the complexity of the soils 

structure and hydrology of the area (Saucier 1994).

One distinct feature of the LMRV is the formation of natural levees along the banks of rivers and the 

associated backwater deposits dominated by dense alluvial clays that historically supported extensive 

wetland areas. The banks of the river can be as much as 10 to 15 feet higher than the lowlands farther back 

from the river. Because of these natural levees, drainage within the floodplain, frequently flows away from 

the Mississippi River to lower elevations near the valley walls, except near tributary confluences. 

Bottomland drainage is provided by streams running parallel to the river and joining it through major 

tributaries or at points where the river meandered close to the valley wall. The clays that formed these 

features have low permeability and limit the ability of rainwater to infiltrate the ground surface (Kleiss et al. 

2000). 

2. Flood-Related History. French settlers began constructing the first levee on the Mississippi 

River in 1717 to protect the fledgling City of New Orleans from high water. That original levee was

only 3 feet high and 5,400 feet long. The French, and later the Spanish, extended the modest levee 

system up the river, but progress was slow with the bulk of the work left to the landowners along the 

river. By 1802, the levees extended as far north as Baton Rouge; by 1849, they had almost reached 

the mouth of the Arkansas River along the west bank. Each landowner built his section of levee 

according to his own design and capability. In 1850, the Swamp Lands Act transferred low lying 

lands to the states, the sale of which allowed the states to fund levee construction. Levee boards were 

set up in the various counties along the river, and the Corps of Engineers provided technical guidance. 

The Civil War interrupted all progress on the levees and navigation improvements along the LMR.

Ongoing flooding and navigation issues led to the creation of the MRC in 1879. Public opinion at that time 

was opposed to Federal intervention for protection of private property in times of flood. Between 1879 and 

1917 appropriations for flood control were publicly proclaimed to be for navigation, but progress on the 

levees continued. The floods varied in stage and duration and each one led to changes in how levees were 

constructed and provided impetus for more coordinated levee systems. 

The FCA of 1917 appropriated $45 million with three provisions: 1) levees were authorized for the 

purpose of flood control; 2) local interests had to contribute 1/3 of the cost of levee construction; and 

3) the MRC was authorized to use funds on the tributary streams to protect the Upper Mississippi 

River Basin from flooding. Work continued on the levee system and in 1926 the MRC believed “the 

day when the Lower Mississippi Valley would be safe from the ravages of floods was within sight.” 
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The most important historical flood, with respect to the MR&T System, was the Flood of 1927. The 

Flood of 1927 began with heavy rains that pounded the central basin of the Mississippi in the summer 

of 1926. By September, swollen tributaries were pouring through Kansas and Iowa. From December 

1926 to April 1927, heavy rains continued throughout the central areas of the basin. There were three 

flood waves on the lower Mississippi in January, February and April, increasing in magnitude each 

time. In February, the White and Little Red Rivers broke through the levees in Arkansas, flooding 

more than 100,000 acres with 10 to 15 feet of water. 5,000 people were left homeless.

The April rains were very intense and river stages rose rapidly. By April 9, more than one million acres of 

land were flooded, and the rain continued to fall. On April 19, a levee near New Madrid, MO, burst, 

flooding an additional one million acres. Portions of seven states (Missouri, Illinois, Kentucky, Tennessee 

Arkansas, Louisiana, and Mississippi) were under water.

At Mounds Landing near Greenville, MS, a flood surge blew out another levee. Swirling eastward, the flood 

ravaged 2.7 million acres of farmland before rejoining the mainstem of the Mississippi at Vicksburg, MS. 

The levee break at Mounds Landing was the greatest single crevasse ever to occur on the Mississippi River. 

It flooded an area 50 miles wide and 100 miles long with up to 20 feet of water. It put water over the tops of 

houses 75 miles away. There were numerous breaks in the levees on the west bank of the river, also, 

inundating lands as far west as Monroe, LA. The flood continued south and west toward the City of 

Melville and the fast-running Atchafalaya River. It swept through town leaving much of it severely 

damaged.

By August 1927, when the flood finally subsided, the disaster had displaced about 700,000 people. It is not 

known exactly how many died in the great disaster. Historians once estimated the death toll at 250 victims, 

but deaths due to disease and exposure after the immediate flood are hard to tally; some estimates exceed 

1,000 deaths. Twenty-six thousand square miles were inundated to depths up to 30 feet, levees were 

crevassed, and cities, towns and farms lay waste. Crops were destroyed and industries and transportation 

paralyzed. 

At a time when the Federal budget barely exceeded $3 billion, the flood, directly and indirectly, caused an 

estimated $1 billion in property damage. It was a disaster of tremendous proportion, awakening the national 

conscience to the need for a comprehensive program to reduce flood risks within the LMR. The 1927 flood 

also illustrated that the “levees only” approach was inadequate to control and safely handle the river’s flood 

flows. Chief Engineer General Edgar Jadwin’s plan differed from the "levees only" approach in three major 

respects: 1.) the incorporation of floodways to divert peak flows and hold down stages in the main channel; 

2.) backwater areas to divert peak flows from the river and store a portion of the flood waters near the peak 

of the flood resulting in reduced downstream stages; and 3.) designing all works on the basis of a PDF -- a 

great hypothetical flood derived from examining historic rainfall and runoff patterns.

This initial system of works was formalized in the 1928 FCA, which authorized the Jadwin Plan, or what 

came to be known as the Mississippi River and Tributaries Project. The features of the plan provided for 

higher and stronger levees, set back from the main channel where feasible. To avoid significant increases in 

levee heights, the plan provided for five floodways—the BPNM, Boeuf, Bonnet Carré, and East and West 

Atchafalaya floodways (note: Boeuf was later substituted by Morganza)—to safely divert excess waters 

past critical reaches in the levee system to prevent flows from exceeding MR&T levee design elevations. 

The plan also provided the revetment of caving banks and channel stabilization features to improve 

navigation.

The 1929 flood tested the new levees. For the first time, all of the mainline levees held.
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The Great Flood of 1937 along the Ohio and lower Mississippi River Valleys provided the first test of the

entire MR&T flood control project and, more precisely, of the BPNM Floodway. The flood was caused by

flow from the Ohio River. Although the Mississippi River above Cairo, IL was at a low stage, the combined 

flows of the Ohio and Mississippi Rivers surpassed the highest flood stages ever experienced between Cairo 

and Helena, AR. On January 24 and 25, 1937, the BPNM Floodway was artificially crevassed. At crest 

stage, the MRC estimated that the Floodway was passing approximately one-fourth of the entire flood 

discharge at Cairo. If the floodway had not been artificially crevassed, most of the Floodway would still have 

been flooded as a result of natural crevasses and overtopping along the frontline levee. Major floods along the 

Lower Mississippi River followed in 1945, 1950, 1973, 1975, 1979, 1983, 1997 and 2008. The Bonnet Carré 

Spillway was operated for each of these floods, but the Morganza Floodway was operated only in 1973.

The PDF flows are greater in magnitude than those of both the 2011 and 1927 floods from Cairo, IL to 

Red River Landing. At Cairo, IL, the PDF is estimated at 2,360,000 cfs. The 1927 Flood was about 

91% of the PDF at the mouth of the Arkansas River and about 76% of the PDF at the latitude of Red 

River Landing, amounting to 3,030,000 cfs at the latter location about 60 miles below Natchez, MS. 

Based on stage and flow rates, the 2011 Flood was approximately 85 percent of the PDF through large 

portions of the MR&T System. It is worth noting that the MR&T System was approximately 89% 

complete during the 2011 Flood. Thus, it likely could not pass the PDF prior to nor after the 2011 

Flood (until it is completed).

Figure II-5 displays a comparison of the inundation extents of the 1927 and 2011 Floods. 
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Figure II-5. Inundation Comparison: 1927 Flood vs. 2011 Flood
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3. MR&T Project Status. Since 1928, the Federal Government has invested approximately $13.9 

billion in the MR&T Project. In 2008, it was estimated that $500 million was needed annually to permit 

efficient completion of programmed construction and operation and maintenance. Prior to 2011, the MR&T 

received one-third to one-half of its funding through Congressional adds. In 2008, which was typical of this 

era, the total Project allocation was $387,402,000, broken down as:

• $196,601,000 (50.7%) - construction (re-evaluation studies, PED, & construction)

• $181,700,000 (47%) - maintenance

• $9,101,000 (2.3%) - planning

Prior to the 2011 Flood, the MR&T System was approximately 89 percent physically complete with a 

remaining balance-to-complete cost of approximately $3 billion and an estimated date of completion of 

2031. The priorities for the known deficiencies change over time are tracked and regularly reassessed in 

Master Plans for the Mississippi River Levee System and Channel Improvements Program.

Prior to the flood, some reaches of the mainline Mississippi River Levees could not safely convey the PDF, 

and other reaches were in need of work to prevent failures due to seepage or deficient cross sections. 

Additionally, channel improvements were needed to assure that alignment of the Mississippi River remained 

stable to provide a dependable navigation channel and to prevent the meander of the river from destroying 

MR&T System features. 

Detailed information related to the incomplete portions of the levee system is provided in Appendix B. It is 

worth noting in this report that many of the deficiencies that were identified as high priorities prior to 

the 2011 Flood are associated with significant flood fight issues and damages that are discussed in 

subsequent sections of this report. Many of these pre-existing deficiencies were identified as high 

priorities prior to the 2011 flood. Some had designs underway to repair the deficiency and construct 

as funding allowed. The magnitude of this flood further deteriorated the conditions, expanded the 

scope of the deficiency, and/or revealed unacceptable vulnerabilities thus elevating the need for repairs 

and supplemental funding to expedite construction. 

4. Environmental Conditions. The LMRV extends from its northern extent at Cape Girardeau, MO to 

its southern delta and covers 36,000 square miles of diverse forest, grasslands, swamps, and marshes. The 

LMRV includes the Atchafalaya, Red, Yazoo, Arkansas, White, and St. Francis River Basins, and the 

Mississippi River Delta plain sub-regions. Each of these has its own unique physiographic character and 

wildlife community. The LMR is typically defined as the stretch of the river downstream of its confluence 

with the Ohio River.

a. Terrestrial Resources

i. Land Resources. The LMR leveed floodplain, which includes the floodplain contained 

between the levees (i.e., the batture) and backwater areas, is a dynamic freshwater ecosystem, often changing 

markedly in response to the river’s annual hydrologic regime. The 2.8 million-acre leveed floodplain (area

between the levees) is interspersed with abandoned channels, meander scars, and large expanses of forested 

wetlands. These areas provide a diverse array of aquatic habitat types and are connected to the river at high 

water. Table II-1 displays the distribution of primary environments within the floodplain areas. 
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Table II-1. Distribution of Environments Within the LMRV

Environment

Area (acres)

(% total)

Bottom land hardwood forests 981,887 (35 %)

Agricultural Lands 478,345 (17 %)

Open Water 515,656 (18 %)

Backwater Areas 680,800 (24 %)

Other 137,186 (6 %)

Total 2,793, 874

Bottom land hardwood forests (BLHF) fill an important ecologic niche in the southern United States, and 

area valuable source of many natural resources (e.g., timber, recreation) and as the primary habitat for a wide 

range of organisms. While BLHF make up a sizeable fraction of the leveed floodplain, agriculture and 

timber harvesting have drastically diminished their national distribution since the time of first Europeansettlement. The construction of various levee systems, drainage efforts, channelization, and land clearing

has altered the natural patterns of surface water drainage within the region, which has affected the 

distribution of ecosystems, such as BLHF, by increasing water availability in some regions and decreasing it 

in others. Table II-2 offers some examples of the wealth of flora currently found in BLHFs as well as in 

backwater wetland areas of the LMR region.

Table II-2. Vegetation Typically Found in Various Environments of the LMRV

Environment Typical Trees Typical Understory

BLHF

water oak (Quercus nigra); Nuttall oak 

(Q.nuttallii); cherrybark oak (Q.falcata); 

native pecan (Carya illinoensis); red maple 

(Acer rubrum var.drummondii); sweetgum 

(Liquidambar styraciflua); and eastern 

cottonwood (Populus deltoides).

palmetto (Sabal minor); greenbrier 

(Smilax rotundifolia); muscadine 

(Vitis rotundifolia); and poison ivy 

(Toxicodendron radicans).

Backwater Areas/ Wetlands

cypress (Taxodium distichum); water 

tupelo (Nyssa aquatic); water oak; green

ash (Fraxinus pennsylvanica); red maple; 

and black willow (Salix nigra).

buttonbush (Cephalanthus

occidentalis); lizardtail (Saururus 

cernuus); water hyacinth (Eichhornia 

crassipes); sedges; and rushes.

The LMRV contains many different types of wetlands including those found within forested areas, river 

valley backwater areas, and around areas of open water. The Atchafalaya River Basin within the LMRV 

contains over a 500,000 acres of wetlands alone, making it the largest “river swamp” in North America. 

Over 40 percent of our Nation’s coastal wetlands are found in Louisiana. Some of these coastal wetlands 

rely upon the Mississippi River for freshwater, sediments, and nutrients. Wetlands surrounding the 

Mississippi River are prime winter foraging grounds for many species of birds that rely heavily on the 

Mississippi flyway for migration. Approximately 70 percent of the Nation’s migratory waterfowl travel 

through the Mississippi flyway annually. Unfortunately, much of the coastal wetlands within the Mississippi 

River delta region are decreasing in area (wetland loss rate of 16.57 mi2 per year, trend analyses 1985 -

2010) due to land loss and submergence caused by both natural and anthropogenic subsidence and altered 

surface water hydrology. 

ii. Wildlife Resource. The BLHF and coastal wetland ecosystems are extremely productive 

wildlife and fisheries habitat (table II-3). For example, 34 mammalian, 164 avian, 39 reptilian, and 20 

amphibian species have been documented within the backwater wetlands near the junction of the Red, 

Atchafalaya, and the Mississippi Rivers. The activities relating to the abundant wildlife resources within the 
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LMR ecosystem, such as hunting and eco-tourism, are a significant source of revenue for the surrounding 

local economies. 

Table II-3. Animals Typically Found in Various Environments of the LMRV

Environment Typical Wildlife

BLHF

white-tailed deer, raccoon, woodpeckers, owls, various songbirds, 

rabbits, mice, wild turkey, and squirrel.

Agricultural Lands cottontail rabbit, mourning dove, raccoon, coyote, and opossum.

Open Water migratory, waterfowl, herons, egrets, and wood ducks

Backwater Areas/Wetlands

muskrat, nutria (invasive), swamp rabbit, mink, river otter, and 

beaver

Three threatened or endangered (T/E) animal species are found throughout the LMRV; the Louisiana black 

bear (Ursus americanus luteolus), the interior least tern (Sterna antillarum), and the pallid sturgeon 

(Scaphirhynchus albus). The endangered fat pocketbook mussel (Potamilus capax) is also found in the 

river. An additional 16 T/E species are also found along the Mississippi River delta plain, such as the piping 

plover (Charadrius melodus), West Indian manatee (Trichechus manatus), and five species of sea turtle 

(e.g., Leatherback (Dermochelys coriacea). The Louisiana black bear’s habitat primarily includes the 

Tensas River basin, the upper Atchafalaya River Basin, and the coastal St. Mary and Iberia parishes in 

Louisiana. The bear favors large cypress and tupelo trees for winter denning, and there is an effort to protect 

areas where these trees are abundant. It is estimated that agricultural development along the Mississippi 

River has reduced the bear’s natural geographic range by 80 percent. The interior least tern was listed as an 

endangered species in 1985, and while its range includes riverine areas throughout the interior United States, 

relatively large populations frequent the Mississippi River between Cape Girardeau, MO southward to 

Vicksburg, MS. 

b. Aquatic Resources

i. Water Resources. The aquatic resources of the LMRV include the main stem of the 

Mississippi River, its tributaries and floodplain side-channels, and both natural and man-made surface water 

impoundments (e.g., floodplain pools, borrow pit ponds, oxbow lakes, reservoirs, and estuaries). The 

Mississippi River and its side channels compose the majority of the aquatic area of the region for most river 

discharges.

The aquatic health and water quality within many LMRV aquatic ecosystems have been degraded due to 

several anthropogenic causes including: 1) agricultural runoff containing pesticides (e.g., atrazine and 

metolachlor) and fertilizers; 2) river engineering for flood management and navigation (i.e., channelization, 

levee construction); 3) aquifer depletion (which lowers summer base-flows beyond acceptable limits for 

many aquatic organisms); and 4) altered fluvial sedimentation regimes (e.g., impounding sediment behind 

dams, increasing sediment yields due to deforestation). Additionally, coastal aquatic areas are affected by 

canal construction, oil and gas exploration, sediment diversion, sea level rise, subsidence, and storm 

damages.

Table II-4 displays median water quality values for the Mississippi measured near Vicksburg, MS. These 

values typically do not significantly vary in space for the lower river reaches. Nutrients, originating from 

agricultural fertilizer, are the primary driver of hypoxic conditions (when dissolved oxygen dips below 2 

parts per million [or 2 mg/L]) observed in the Gulf of Mexico. Approximately 90 percent of the Mississippi 

River’s nitrate load originates from non-point sources within its upper basin and the Ohio River valley. 

Recently observed hypoxia in Mississippi Sound and Gulf Coast waters east of the Mississippi River may be 
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linked to operation of the Bonnet Carré Spillway in 2008 and 2011 (Gundersen et al., 2012). A waterquality monitoring program for both the Mississippi River (employing five permanent water-quality 

measuring stations) and Atchafalaya River (employing two permanent water-quality measuring stations) has 

been established by the US Geological Survey (USGS) NASQAN program. Louisiana currently permits 

approximately 300 industrial and municipal sites to discharge wastewater into the Mississippi River, while it 

is used as the primary source of municipal water supply for approximately 1.5 million people.

Table II-4. Median Water Quality Values for the Mississippi River at Vicksburg

During the Spring/Summer Flood Season

Water Quality Metric Value

Suspended Sediment ~170.0 mg/L 1

Nitrogen ~2.2 mg/L

Phosphorus ~0.2 mg/L

Metolachlor & Atrazine ~1.0 mg/L

The LMRV aquatic ecosystems have been significantly impacted from the introduction of invasive species. 

Invasive species threaten the diversity and abundance of native species, the ecological stability of infested 

waters, and the commercial, agricultural, aqua-cultural, and recreational activities dependent on those 

ecosystems. Five species of Asian carp [grass carp (Ctenopharyngodon idella), common carp (Cyprinus 

carpio), silver carp (Hypophthalmichthys molotrix), bighead carp (H. nobilis), and black carp 

(Mylopharyngodon piceus)] have invaded much of the LMRV. Common carp have been present since the 

mid-1800s while the other species have invaded within the last three to four decades. All of these fish have 

degraded native fish and possibly mussel populations by increasing competition for their food sources and 

habitat. Silver carp also pose a safety concern to boaters due to their propensity for jumping out of the water 

in front of moving vessels. Zebra mussel (Dreissena polymorpha) infestations have the potential to cause 

ecological changes in the major rivers of the LMRV as observed in the upper Mississippi River region. 

Their rapid reproduction, coupled with their ability to consume large quantities of microscopic plants and 

animals, degrades their local aquatic food web and places valuable commercial and sport fisheries at risk. 

The LMRV is also presently home of a number of invasive aquatic plants, such as giant salvinia, purple 

loosestrife, Eurasian watermilfoil, water hyacinth, water lettuce, hydrilla, etc., that quickly establish 

themselves and often replace native plants. 

The coastal estuaries surrounding the Mississippi River delta, which includes areas stretching from Lake 

Pontchartrain to the Mississippi Sound and west to the Barataria Basin, are an extremely productive and 

robust ecosystem. Nutrient-rich fresh water from inland rivers, including the Mississippi River, mix with the 

saline sea water, creating a diverse range of coastal habitats. These areas are highly prized for recreational 

and commercial fishing for such species as spotted seatrout, blue crab, brown shrimp, and oysters. Many of 

Louisiana’s coastal bays and Gulf waters to the three-mile limit are listed as impaired (i.e., not supporting 

designated uses) due to causes ranging from mercury in fish tissue to low dissolved oxygen [Louisiana 

Department of Environmental Quality’s s 2010 Water Quality Inventory: Integrated Report 

(305(b)/303(d)].

ii. Fisheries. The waters of the LMRV support over 150 species of freshwater fish. The 

diversity and abundance of aquatic wildlife typically increases southward with increasing proximity to the 

river estuary. The mainstem of the Mississippi River may contain over 100 species in a short reach, 

including minnow, darters, suckers, catfish, and sturgeon. The pallid sturgeon (Scaphiryhnchus albus) was 

federally listed as an endangered species in 1990 and has been observed above New Orleans on the main 

stem of the river. Gravel bars within the main river are vital spawning habitat for sturgeon and other species 

of concern, such as paddlefish. While large dike pools in the Mississippi River can support 1,000 pounds of 
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fish per acre, slackwater areas like borrow pit ponds support up to 600 pounds per acre including uncommon 

and imperiled wetland species (e.g., pugnose minnow, taillight shiner, paddlefish and alligator gar). Spring 

floods provide necessary access between swift river water and slower-moving floodplain side-channels and 

ponds, which fish use for enhanced forage and spawning.

There is a range of native freshwater mussel species present within the LMRV; however, water quality 

issues and channel modifications have caused significant declines in freshwater mussel populations. 

Channel responses such as headcutting and knickpoint migration, caused the deterioration of several 

populations. The fat pocketbook mussel (Potamilus capax) was listed as an endangered species in 1976. 

After the species was listed, populations were located in the St. Francis River and Gilliam’s Chute. In recent 

years, its range has expanded to include other backwater, clayey river channels in southern Arkansas and 

Mississippi.

The Mississippi River and Atchafalaya River estuaries produce a large fraction of our Nation’s fisheries and 

are critical habitat for gulf coast oysters and other shellfish. The Mississippi River estuary and northern gulf 

coast are key commercial fishing ground for many salt-water species including bay anchovy (Anchoa 

mitchilli), Atlantic croaker (Micropogonias undulatus), gulf menhaden (Brevoortia patronus), blue 

crab (Callinectes sapidus), northern brown shrimp (Farfantepenaeus aztecus), and white shrimp 

(Litopenaeus setiferus).

5. Cultural Resources. The alluvial valley of the Mississippi River was one of the most densely 

populated areas of North America in prehistoric (pre-European contact) times. Consequently, there are 

thousands of archaeological sites ranging from post-glacial Paleo-Indian to late prehistoric 

Mississippian cultures. A unique cultural florescence, not found anywhere else, known as the Poverty 

Point culture also developed in the valley during the late Archaic period, approximately 3,000 

thousand years ago. Hundreds of archaeological sites have been listed on the NRHP, and a far greater 

number have been determined eligible for the NRHP. In addition, the floodplain contains a rich 

historic archaeological record, including French and Spanish colonial sites, 19th century antebellum 

mansions associated with the mythic old South (e.g., Oak Alley Plantation), Civil War sites, 

sharecroppers farms, and a wide variety of 19th and 20th century historic buildings and sites that 

together form a unique and irreplaceable archaeological record. Remnants of more than 300 

nineteenth century plantation sites have been recorded within the MVN alone. 

To illustrate the LMRV’s unique prehistoric archaeological heritage, it should be noted that around 

1,000 A.D., larger, more complex mound sites were erected by late prehistoric Mississippian cultures. 

The flat-top earthen temple mounds within the large towns of these Mississippian peoples are still 

evident across the LMRV. In the lower valley, the Emerald Mound site, the second largest 

Mississippian mound (next to Monk’s Mound at Cahokia) lies just north of Natchez and close to the 

present course of the Mississippi River. 

During the early historic (colonial) period the Natchez, the Tunica, the Quapaw, the Choctaw and the 

Chickasaw constructed village sites in close proximity to the Mississippi River and its major 

tributaries. While some of these village sites have been preserved, many have been lost. Levee 

construction, erosion, and other land disturbances (e.g., the great New Madrid earthquake of 1811-

1812) have destroyed many prehistoric and historic archaeological sites on the river side of the levee. 

During the 1830s, the Mississippi River and major tributaries like the Arkansas River served as the 

major transportation corridor for the forced removal of the Five Civilized Tribes after the Indian 

Removal Act of 1830. 
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Another major category of historic properties is the largely unknown number of 19th century steamboat 

wrecks, which occurred during the height of steamboat navigation on the Mississippi, described so 

vividly in Mark Twain’s classic Life on the Mississippi. In 1988, record low-water levels provided the 

Arkansas Archaeological Survey with an opportunity to examine a sample of these shipwrecks when 

the Mississippi River fell to 10 feet below zero on the Memphis gauge and exposed four and a half 

acres of 19th century water craft remains on the riverbed near Memphis. The Survey’s archaeological 

fieldwork received national media attention and wide publication in academic and popular journals. 

This high density of previously unknown shipwrecks in the Memphis area would probably be found at 

other large river towns (e.g., Vicksburg and Natchez, MS) in the Study area. However, most of these 

steamboat wrecks have never been formally recorded or evaluated for the NRHP. Systematic 

underwater surveys, using side-scan sonar and magnetometers, have yet to be done in the Mississippi 

River Valley and its major tributaries. 

6. Social/Economic Background. A comprehensive overview of the overall area affected physically 

or economically by the MR&T Project on the surrounding region is presented in order to provide the context 

and basis needed to understand and determine flood-related impacts along the lower reaches of the 

Mississippi River from Cape Girardeau, MO, to the Head of Passes, LA. This synopsis includes a 

description of the economic base area and its historical significance to the general region; a background of 

the MR&T Project; and a discussion of other Mississippi River improvements and accomplishments. A 

special emphasis is given to significant impacts relevant to project implementation. This includes a 

discussion of project effects regarding the economy, flood damages prevented by the Project, and other 

related impacts or contributions from the Project.

a. Background. The MR&T Project is vital to overall FRM within the Lower Mississippi River. 

Because of its low-lying valleys, flooding on the LMR threatens cities, property, and crops along its banks. 

The mainline levees are also continuously being upgraded to correct deficiencies following major floods 

(e.g., 1973 and 2011). It is expected, that when all upgrades have been completed, this project will provide 

FRM to an estimated population of about 6.4 million people in 119 counties and parishes along the 

Mississippi River. 

b. The Economic Base Area. The impacted area encompasses approximately 71,800 square miles 

of land area considered to be physically, socially, or economically impacted by the MR&T Project. This 

economic base area used to assess economic impacts of the MR&T was larger than the 36,000-square-mile

LMRV because it included full census block areas which may extend beyond the boundaries of the LMRV. 

This base area extends roughly from Cairo, IL, to the Gulf of Mexico, includes portions of seven states—

Arkansas, Illinois, Kentucky, Louisiana, Mississippi, Missouri, and Tennessee—and five Corps Districts 

along the LMR and tributaries region—Little Rock, AR (SWL), , Memphis, TN (MVM), MVN, MVR, 

MVS, and MVK. Thus, to illustrate socioeconomic impacts to each entity, statistical data will be displayed 

by both state and District. Other damages and impacts associated with the 2011 Mississippi River flood in 

these areas are discussed in more detail in Section V.

i. Impacted Areas. The MR&T economic base area begins in the vicinity of the Mississippi 

River's confluence with the Ohio River. At this point, it includes portions of four states—Illinois, Kentucky, 

Missouri, and Tennessee. The northernmost portions of the economic base area impacted by flooding are 

located in the LRL and LRN Districts. Impact areas in the LRL include nearly 1,500 square miles of land 

within 5 counties while damages in the LRN have the potential to impact approximately 500 square miles in 

2 counties. There are about 430 square miles in 2 counties within the MVS. There are also counties that 

overlap multiple Districts, but they are only counted once.
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The portion within the MVM starts at Cape Girardeau and extends southerly along the Mississippi River to 

Memphis, TN. This segment contains approximately 20,200 square miles of land in 35 counties of 5 

states—15 in Arkansas; 4 in Kentucky; 1 in Mississippi; 9 in Missouri; and 6 in Tennessee. To the west, the 

SWL has approximately 2,000 square miles of land in 3 counties that were subjected to impacts from the 

flood.

The portion within the MVK stretches from the MVM boundary southward to the Mississippi River's 

confluence with the Red River in Louisiana. With approximately 31,200 square miles of land area, it 

comprises about 38 percent of the economic base area. This segment comprises 49 counties and parishes in 

three states—11 counties in Arkansas, 16 parishes in Louisiana, and 22 counties in Mississippi. 

The remaining portion, located in the MVN, accounts for the southernmost portion of the LMR region and 

the Atchafalaya River Basin. Situated entirely in the State of Louisiana, this section covers approximately 

17,300 square miles of land in 29 parishes along the Mississippi River from the Red River to the Gulf. A list 

of counties/parishes by state and Corps District is provided in table II-5.

ii. Socio-economic Statistics. The objective of the socioeconomic study is to provide a 

framework from which to help identify and understand the impacts, problems, and needs in the 

affected areas of the 2011 Mississippi River flood. 

There are 119 counties and parishes along the Mississippi River in seven states that impacted by 

Mississippi River flooding. Socioeconomic statistics for 2010 conditions are presented in table II-6 

for each Corps District.
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Table II-5. 2010 MR&T Economic Base Area By District, State, and County/Parish 

LITTLE ROCK DISTRICT

ARKANSAS

Independence Jackson Randolph

MEMPHIS DISTRICT

ARKANSAS KENTUCKY MISSISSIPPI MISSOURI TENNESSEE

Arkansas Mississippi Ballard DeSoto Butler Wayne Dyer

Clay Monroe Carlisle Cape Girardeau Lake

Craighead Phillips Fulton Dunklin Lauderdale

Crittenden Poinsett Hickman Mississippi Obion

Cross St. Francis New Madrid Shelby

Greene White Pemiscot Tipton

Lawrence Woodruff Scott

Lee Stoddard

NEW ORLEANS DISTRICT

LOUISIANA

Acadia Iberville Orleans St. James Tangipahoa

Allen Jefferson Plaquemines St. John the Baptist Terrebonne

Ascension East Baton Rouge Pointe Coupee St. Landry Vermilion

Assumption East Feliciana Lafayette Rapides St. Martin West Baton Rouge

Avoyelles Evangeline Lafourche St. Bernard St. Mary West Feliciana

Iberia Livingston St. Charles St. Tammany

ST. LOUIS DISTRICT

ILLINOIS MISSOURI

Alexander Pulaski Perry Bollinger

VICKSBURG DISTRICT

ARKANSAS LOUISIANA MISSISSIPPI

Ashley Desha Ouachita Caldwell La Salle Tensas Adams Issaquena Tate

Bradley Drew Prairie Catahoula Lincoln Union Bolivar Jefferson Tunica

Calhoun Jefferson Union Concordia Madison West Carroll Carroll Leflore Warren

Chicot Lincoln East Carroll Morehouse Winn Claiborne Panola Washington

Franklin Ouachita Coahoma Quitman Wilkinson

Grant Richland Grenada Sharkey Yazoo

Holmes Sunflower

Humphreys Tallahatchie
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Table II-6. 2010 Socioeconomic Statistics in the MR&T Area by Corps District 1

Socioeconomic Category

SWL

AR

(3 counties)

MVM

AR, KY, MO, MS, TN

(35 counties)

MVN

LA

(31parishes)

MVS

IL

(3 counties)

MVK

AR, LA, MS

(47 counties)

Total

(119)

Land Area (Square Miles) 2,050 20,219 17,295 437 31,162 71,163 

Population Density ( Persons Per Square Mile) 35.4 101.4 178.6 33.1 36.8 77.1 

Total Population, 2010 72,613 2,049,355 3,089,524 14,339 1,148,230 6,374,061 

Total Population, 2000 71,752 1,884,869 2,978,795 15,579 1,210,219 6,161,214 

 Change, 2000-2010 1.2% 8.7 3.7 -7.6% -5.1% 0.9 

Total Number of Households, 2010 28,445 762,995 1,108,307 5,845 418,735 2,324,327 

Persons Per Household 2.55 2.69 2.79 2.46 2.74 2.65 

Median House Unit Value, 2010 2 $70,333 $94,767 $121,683 $98,620 $69,229 $90,926 

Total Employment, 2010 21,641 746,759 1,108,395 2,206 321,969 2,200,970 

Per Capita Income, 2010 2 $17,846 $19,842 $21,970 $17,151 $16,794 $18,720 

Household Income, 2010 2 $30,821 $39,749 $45,057 $30,003 $31,297 $35,385 

Total Value Added by Manufacturing, 2007 (millions) 2 $1,068.1 $37,054.8 $49,560.6 $885,672 $9,671.6 $983,027.1 

Retail Sales, 2007 (millions) 2 $712.6 $25,287 $40,208.9 $1,216.2 $11,490.9 $78,834.7 

Wholesale Sales, 2007 (millions) 2 $309.7 $38,104 $31,942.3 $186.9 $2,525.8 $73,068.7 

Total Number of Farms, 2007 2,332 18,662 12,454 2,682 19,416 55,546 

Total Acres in Farms, 2007 803,925 9,062,089 2,947,472 749,266 2,640,206 16,202,958 

Total Value of Farm Products Sold, 2007 (millions) 3 $345.2 $4,092.6 1119.3 $237.3 $3,869.4 $9,663.8 

1 Statistics presented to represent the closest year to 2010 as available by the US Census Bureau, QuickFacts 2 US Census Bureau values presented in 2010 dollars

3 Values updated from 2007 to 2012 dollars

4 Information not disclosed
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c. Demographic Setting. When reviewing the specific demographics of the areas along the 

Mississippi River, it is evident how the regional economies are reliant, not only on the waters of the 

River itself, but on the agricultural and industrial bases which have developed as a result of the River. 

Appendix G, Economics, provides a comprehensive discussion with detailed demographic statistics by 

county. An almost direct correlation exists between the number of persons residing in a specific area 

and the economic opportunities (especially economic and industrial activity) available in that area. 

Consequently, economic and industrial activity is used as an indicator of labor requirements and of 

local demands for community facilities and public services.

i. Population. Population growth is a direct reflection of the economic growth of an area. 

Population levels are good indicators of the size of an urban area and its land use needs such as residential, 

commercial, and other urban uses. Population statistics are also the basis for any other economic parameters 

such as per capita income (PCI), persons per household (PPH), population density, etc. Population for the 

total area exceeded 6.4 million in 2010, an overall growth of 3 percent over the 6.2 million people reported 

for 2000. Section V of this Report details totals by county and parish.

Historically, population totals for the overall region have gradually increased. However, there have 

been some periods of outmigration in localized rural areas where the number of persons moving out of 

an area was greater than the combined number of immigrating residents and the natural population 

growth. The Mississippi Delta suffered the greatest reduction in the total number of persons living in 

the area. However, growth statistics show the overall study area population has increased by over 

500,000 people from 1960 to 1990 or 14 percent over the 30-year period.

Population growth within the study area has fluctuated from area to area based on varying factors. In 

many cases, areas within counties in close proximity to large metropolitan centers have enjoyed 

substantial population growth. This is evident in reviewing the population trends of counties which 

encompass large cities. These urban centers offer a diversified economic base of jobs, industry, and 

services which provide for the basic needs of a large population—employment, income, and housing.

Although the area is predominantly rural, there are over 50 cities situated along the Mississippi River 

that have populations of 10,000 people or greater (table II-7). There were also over 100 towns with 

populations between 2,500 and 10,000 people during the last Census. The largest population centers 

impacted by the MR&T Project are the Metropolitan Statistical Areas (MSA), which are the major 

commercial, services, and industrial centers for regional areas. Among these are Louisville, Pine 

Bluff, and West Memphis, AR; Baton Rouge, Monroe, and New Orleans, LA; St. Louis, MO; and 

Memphis, TN. In addition to their close proximity to the Mississippi River, each of the major 

metropolitan centers has international air service and is accessible by multiple Interstate and Federal 

highway systems. Thus, when floods of the magnitude of the 2011 occur, disruptions of numerous 

services take place.

ii. Housing. Data reported on housing units provide insight into significant social 

developments that influence the economic activity of an area. According to the latest Census, there 

were 2.3 million housing units located in the economic base area in 2010. The number of PPH for the 

MR&T area compares with the national average. Applying the total population to the total number of 

households, the number of PPH for the 119-county area was estimated to be 2.65 PPH for 2010. The 

national PPH for 2010 (2.59) is only slightly lower. These numbers reflect a trend (i.e., smaller 

families) that has been occurring nationally in recent decades. 

The total median value of housing units, presented in 2010 dollars, ranged from highs of $203,000 and 

$201,000 in Plaquemines and St. Tammany Parishes, LA, respectively, to lows of $46,000 and $44,000 

in Quitman County, MS, and East Carroll Parish, LA. In comparing state totals, Illinois had the highest 

housing value at $202,500. The national value for 2010 was reported to be $188,400.
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Table II-7. Urban Areas in the Economic Base Area 1

SWL MVM MVN MVS MVK

Arkansas

Batesville

Little Rock

Arkansas

Blytheville

Forrest City

Helena-West Helena

Jonesboro

Paragould

Searcy

Stuttgart

Illinois

Cairo

Cape GirardeauMissouri

Jackson

Kennett

Sikeston

Missouri/Illinois

Jackson

Kentucky

Paducah

Tennessee

Bartlett-Collierville-

 Germantown-Memphis

Brownsville

Dyersburg

Humboldt

Jackson

Martin

Kentucky/Tennessee

Union City

Louisiana

Abbeville

Baton Rouge

Crowley

DeRidder

Hammond

Houma

Kenner

Lafayette

Lake Charles

Metairie

Morgan City

New Iberia

New Orleans

Opelousas-Eunice

Illinois

Carbondale 

Missouri

St. Louis

Illinois/Missouri

Cape Girardeau/

 Jackson 

Arkansas

El Dorado

Pine Bluff

Louisiana

Alexandria

Bastrop

Monroe

Ruston

Vidalia

Mississippi

Batesville

Clarksdale

Cleveland

Greenwood

Greenville

Grenada

Indianola

Natchez

Tunica

Vicksburg

Yazoo City

1 Places with greater than 10,000 people

d. Economic Setting. Economic conditions can be described by parameters such as 

labor force and employment, earnings and income, agricultural activity, and industrial and 

business activity. 

i. Employment. Total employment in the study area represents the number of wage and 

salary employees and the number of proprietors. Total private nonfarm employment for 2010 was 

estimated to be approximately 2.5 million people for the total economic base area, a 32 percent growth 

since 1990. The total employment in the study area in 1990 was estimated at 1.9 million, which was a 

33 percent increase over the 1970 employment of 1.4 million. The majority of the economic base 

employment occurs in counties with large urban populations (e.g., the MSAs of Little Rock, Memphis, 

New Orleans, and St. Louis). 

ii. Income. In 2010, the average per capita income in the economic base area ranged from 

a low of $11,800 in Lake County, TN, to a high of $29,300 in St. Tammany Parish, LA. Overall, PCIs 
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for the counties averaged about $19,831 per person in 2010 in the MR&T area. However, the PCI for 

the majority of the states was much higher, as follows, from highest to lowest:

Illinois $28,782 Missouri $24,724

Tennessee $23,722 Louisiana $23,094

Kentucky $22,515 Arkansas $21,274

Mississippi $19,977

In comparison, the national PCI was $27,334 for 2010. Based on detailed socioeconomic studies, the 

major sectors contributing toward total earnings are the services, transportation, manufacturing, retail 

trade, government, and farming industries. Although farming and forestry have historically been 

major enterprises in the past, services and manufacturing have become increasingly important to the 

economy over the last decades. Much of this is due to increased efforts toward mechanization and 

industrialization of production processes and the infiltration of a diversity of industries into the region. 

Services and manufacturing were the leading contributors to earnings in 2010.

iii. Agriculture. Favorable agricultural characteristics have been significant factors in the 

development of land use patterns in the area. Historically, agricultural resources have been important 

to the economy of the region. However, along with industrial expansion and the increased 

commercialization and mechanization of farms, farming operations have followed a national trend of 

consolidation resulting in fewer farms with larger acreages. In 2007, there were 55,546 farms in the 

economic base area comprising 16.2 million acres, with an average size per farm of 292 acres.

The total value of farm products sold in 2007 was estimated to be $9.7 billion (indexed to 2012 

dollars). As a major contributor to the economies of many counties in the area, agricultural 

production, especially in the rich Mississippi River Delta lands, remains a viable industry in the 

region.