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Thursday, September 11, 2014

Mississippi River

Mississippi River

From Wikipedia, the free encyclopedia

Mississippi River
Efmo View from Fire Point.jpg
Mississippi River near Harpers Ferry, Iowa
Name origin: Ojibwe word misi-ziibi, meaning "Great River", or gichi-ziibi, meaning "Big River"

Country United States
States Minnesota, Wisconsin, Iowa, Illinois, Missouri, Kentucky, Tennessee, Arkansas, Mississippi, Louisiana

Tributaries
 - left St. Croix River, Wisconsin River, Rock River, Illinois River, Kaskaskia River, Ohio River
 - right Minnesota River, Des Moines River, Missouri River, White River, Arkansas River, Red River
Cities Minneapolis, MN, St. Paul, MN, La Crosse, WI, Quad Cities, IA/IL, St. Louis, MO, Memphis, TN, Baton Rouge, LA, New Orleans, LA


Source Lake Itasca[1]
 - location Itasca State Park, Clearwater County, MN
 - elevation 1,475 ft (450 m)
 - coordinates 47°14′23″N 95°12′27″W
Mouth Gulf of Mexico
 - location Pilottown, Plaquemines Parish, LA
 - elevation 0 ft (0 m)
 - coordinates 29°09′04″N 89°15′12″W

Length 2,340 mi (3,766 km)
Basin 1,151,000 sq mi (2,981,076 km2)
Discharge for mouth; max and min at Baton Rouge, LA
 - average 593,000 cu ft/s (16,792 m3/s) [2]
 - max 3,065,000 cu ft/s (86,791 m3/s)
 - min 159,000 cu ft/s (4,502 m3/s)

Detailed map of Mississippi River tributary structure

The Mississippi River is the chief river of the largest drainage system in North America.[3][4] Flowing entirely in the United States (though its drainage basin reaches into Canada), it rises in northern Minnesota and meanders slowly southwards for 2,340 miles (3,770 km)[4] to the Mississippi River Delta at the Gulf of Mexico. With its many tributaries, the Mississippi's watershed drains all or parts of 31 US states and 2 Canadian provinces between the Rocky and Appalachian Mountains. The Mississippi ranks as the fourth longest and tenth largest river in the world. The river either borders or passes through the states of Minnesota, Wisconsin, Iowa, Illinois, Missouri, Kentucky, Tennessee, Arkansas, Mississippi, and Louisiana.

Native Americans long lived along the Mississippi and its tributaries. Most were hunter-gatherers or herders, but some, such as the Mound builders, formed prolific agricultural societies. The arrival of Europeans in the 1500s changed the native way of life as first explorers, then settlers, ventured into the basin in increasing numbers. The river served first as a barrier – forming borders for New Spain, New France, and the early United States – then as a vital transportation artery and communications link. In the 19th century, during the height of Manifest Destiny, the Mississippi and several western tributaries, most notably the Missouri, formed pathways for the western expansion of the United States.

Formed from thick layers of this river's silt deposits, the Mississippi River Valley is one of the most fertile agricultural regions of the country, which resulted in the river's storied steamboat era. During the American Civil War, the Mississippi's capture by Union forces marked a turning point towards victory because of the river's importance as a route of trade and travel, not least to the Confederacy. Because of substantial growth of cities and the larger ships and barges that supplanted riverboats, the decades following the 1900s saw the construction of massive engineering works such as levees, locks and dams, often built in combination.

Since modern development of the basin began, the Mississippi has also seen its share of pollution and environmental problems – most notably large volumes of agricultural runoff, which has led to the Gulf of Mexico dead zone off the Delta. In recent years, the river has shown a steady shift towards the Atchafalaya River channel in the Delta; a course change would prove disastrous to seaports such as New Orleans. While a system of dikes and gates has held the Mississippi in its current channel to date, the shift becomes more likely each year due to fluvial processes.

Name

The word itself comes from Messipi, the French rendering of the Anishinaabe (Ojibwe or Algonquin) name for the river, Misi-ziibi (Great River). See below in History section for additional information.
In addition to historical traditions shown by names, there are at least two other measures of a river's identity, one being the largest branch (by water volume), and the other being the longest branch. Using the largest-branch criterion, the Ohio (not the Middle and Upper Mississippi) would be the main branch of the Lower Mississippi. Using the longest-branch criterion, the Middle Mississippi-Missouri-Jefferson-Beaverhead-Red Rock-Hellroaring Creek River would be the main branch. According to either school of thought, the Upper Mississippi from Lake Itasca, Minnesota to St. Louis, despite its name, would only be a secondary tributary of the final river flowing from Cairo to the Gulf of Mexico.

While the Missouri River, flowing from the confluence of the Jefferson, Madison and Gallatin Rivers to the Mississippi, is the longest continuously named river in the United States,[4] the serially named river known sequentially as Hellroaring Creek, Red Rock, Beaverhead, Jefferson, Missouri, Middle Mississippi, and Lower Mississippi, as one continuous waterway, is the longest river in North America and the third or fourth longest river in the world. Its length of at least 3,745 mi (6,027 km)[citation needed] is exceeded only by the Nile, the Amazon,[5] and perhaps the Yangtze River[6] among the longest rivers in the world. The source of this waterway is at Brower's Spring, 8,800 feet (2,700 m) above sea level in southwestern Montana, along the Continental Divide outside Yellowstone National Park.

The Mississippi River is widely considered a convenient if approximate dividing line between the Eastern, Southern, and Midwestern United States and the Western U.S., as exemplified by the Gateway Arch in St. Louis and the phrase "Trans-Mississippi," as used in the name of the Trans-Mississippi Exposition.

Physical geography

The geographical setting of the Mississippi River includes considerations of the course of the river itself, its watershed, its outflow, its prehistoric and historic course changes, and possibilities of future course changes. The New Madrid Seismic Zone along the river is also noteworthy. These various basic geographical aspects of the river in turn underlie its human history and present uses of the waterway and its adjacent lands.

Divisions

The Mississippi River can be divided into three sections. The Upper Mississippi refers to the river from its headwaters to the confluence with the Missouri River. The Middle Mississippi is that part downriver from the Missouri to the Ohio River. And the Lower Mississippi flows from the Ohio to the Gulf of Mexico.

Upper Mississippi

The beginning of the Mississippi River at Lake Itasca (2004)
Coon Rapids Dam
Mississippi Head of Navigation: Coon Rapids Dam
Confluence of the Wisconsin and Mississippi Rivers, viewed from Wyalusing State Park in Wisconsin

The Upper Mississippi runs from its headwaters to its confluence with the Missouri River at St. Louis, Missouri. The Upper Mississippi is divided into two sections:
  1. The headwaters, 493 miles (793 km), from the source to Saint Anthony Falls in Minneapolis, Minnesota; and
  2. A navigable channel, formed by a series of man-made lakes between Minneapolis and St. Louis, Missouri, some 664 miles (1,069 km).
The source of the Upper Mississippi branch is traditionally accepted as Lake Itasca, 1,475 feet (450 m) above sea level in Itasca State Park in Clearwater County, Minnesota. The name "Itasca" was chosen to designate the "true head" of the Mississippi River as a combination of the last four letters of the Latin word for truth (veritas) and the first two letters of the Latin word for head (caput).[7] However, the lake is in turn fed by a number of smaller streams.

From its origin at Lake Itasca to St. Louis, Missouri, the waterway's flow is moderated by 43 dams. Fourteen of these dams are located above Minneapolis in the headwaters region and serve multiple purposes, including power generation and recreation. The remaining 29 dams, beginning in downtown Minneapolis, all contain locks and were constructed to improve commercial navigation of the upper river. Taken as a whole these 43 dams significantly shape the geography and influence the ecology of the upper river. Beginning just below Saint Paul, Minnesota, and continuing throughout the upper and lower river, the Mississippi is further controlled by thousands of wing dikes that moderate the river's flow in order to maintain an open navigation channel and prevent the river from eroding its banks.

The head of navigation on the Mississippi is the Coon Rapids Dam in Coon Rapids, Minnesota. Before it was built in 1913, steamboats could occasionally go upstream as far as Saint Cloud, Minnesota, depending on river conditions.

The uppermost lock and dam on the Upper Mississippi River is the Upper St. Anthony Falls Lock and Dam in Minneapolis. Above the dam, the river's elevation is 799 feet (244 m). Below the dam, the river's elevation is 750 feet (230 m). This 49-foot (15 m) drop is the largest of all the Mississippi River locks and dams. The origin of the dramatic drop is a waterfall preserved adjacent to the lock under an apron of concrete. Saint Anthony Falls is the only true waterfall on the entire Mississippi River. The water elevation continues to drop steeply as it passes through the gorge carved by the waterfall.

The Upper Mississippi features various natural and artificial lakes, with its widest point being Lake Winnibigoshish, near Grand Rapids, Minnesota, over 7 miles (11 km) across. Also of note is Lake Onalaska (created by Lock and Dam No. 7), near La Crosse, Wisconsin, over 4 miles (6.4 km) wide. On the other hand, Lake Pepin is natural, formed due to the delta formed by the Chippewa River of Wisconsin as it enters the Upper Mississippi; it is more than 2 miles (3.2 km) wide.[8]

By the time the Upper Mississippi reaches Saint Paul, Minnesota, below Lock and Dam No. 1, it has dropped more than half its original elevation and is 687 feet (209 m) above sea level. From St. Paul to St. Louis, Missouri, the river elevation falls much more slowly, and is controlled and managed as a series of pools created by 26 locks and dams.[9]

The Upper Mississippi River is joined by the Minnesota River at Fort Snelling in the Twin Cities; the St. Croix River near Prescott, Wisconsin; the Cannon River near Red Wing, Minnesota; the Zumbro River at Wabasha, Minnesota; the Black, La Crosse, and Root rivers in La Crosse, Wisconsin; the Wisconsin River at Prairie du Chien, Wisconsin; the Rock River at the Quad Cities; the Iowa River near Wapello, Iowa; the Skunk River south of Burlington, Iowa; and the Des Moines River at Keokuk, Iowa. Other major tributaries of the Upper Mississippi include the Crow River in Minnesota, the Chippewa River in Wisconsin, the Maquoketa River and the Wapsipinicon River in Iowa, and the Big Muddy River and Illinois River.

The Upper Mississippi is largely a multi-thread stream with many bars and islands. From its confluence with the St. Croix River downstream to Dubuque, Iowa, the river is entrenched, with high bedrock bluffs lying on either side. The height of these bluffs decreases to the south of Dubuque, though they are still significant through Savanna, Illinois. This topography contrasts strongly with the Lower Mississippi, which is a meandering river in a broad, flat area, only rarely flowing alongside a bluff (as at Vicksburg, Mississippi).
Exotic species alert for the Mississippi River in Minnesota

The Upper Mississippi River is home to over 119 species of fish. Some fish include; walleye, sauger, large mouth bass, small mouth bass, and white bass. Northern pike, bluegill and crappie also reside in the Upper Mississippi River. Other fish like channel catfish, flathead catfish, carp, the common shiner, freshwater drum, paddlefish and shovelnose sturgeon also live in these upper Mississippi waters.[10][11] The Minnesota Department of Natural Resources has designated much of the Mississippi River in the state as infested waters by the exotic species zebra mussels and Eurasian watermilfoil.[12]
The confluence of the Mississippi and Ohio rivers at Cairo, Illinois, the demarcation between the Middle and the Lower Mississippi River

Middle Mississippi

The Mississippi River is known as the Middle Mississippi from the Upper Mississippi River's confluence with the Missouri River at St. Louis, Missouri, for 190 miles (310 km) to its confluence with the Ohio River at Cairo, Illinois.[13][14]

The Middle Mississippi is a relatively free-flowing river. From St. Louis to the Ohio River confluence, the Middle Mississippi falls a total of 220 feet (67 m) over a distance of 180 miles (290 km) for an average rate of 1.2 feet per mile (23 cm/km). At its confluence with the Ohio River, the Middle Mississippi is 315 feet (96 m) above sea level. Apart from the Missouri and Meramec rivers of Missouri and the Kaskaskia River of Illinois, no major tributaries enter the Middle Mississippi River.

Lower Mississippi

Lower Mississippi River near the city New Orleans

The Mississippi River is called the Lower Mississippi River from its confluence with the Ohio River to its mouth at the Gulf of Mexico. Measured by water volume, the Lower Mississippi's primary branch is the Ohio River. At the confluence of the Ohio and the Middle Mississippi, the Ohio is the bigger river, with its long-term mean discharge at Cairo, Illinois being 281,500 cu ft/s (7,970 m3/s),[15] while the long-term mean discharge of the Mississippi at Thebes, Illinois (just upriver from Cairo) is 208,200 cu ft/s (5,900 m3/s).[16] Thus, by volume, the main branch of the Mississippi River system at Cairo can be considered to be the Ohio River (and the Allegheny River further upstream), rather than the Middle Mississippi.

In addition to the Ohio River, the major tributaries of the Lower Mississippi River are the White River, flowing in at the White River National Wildlife Refuge in east central Arkansas; the Arkansas River, joining the Mississippi at Arkansas Post; the Big Black River in Mississippi; the Yazoo River, meeting the Mississippi at Vicksburg, Mississippi; and the Red River in Louisiana. The widest point of the Mississippi River is in the Lower Mississippi portion where it exceeds 1 mile (1.6 km) in width in several places.

Deliberate water diversion at the Old River Control Structure in Louisiana allows the Atchafalaya River in Louisiana to be a major distributary of the Mississippi River, with 30% of the Mississippi flowing to the Gulf of Mexico by this route, rather than continuing down the Mississippi's current channel past Baton Rouge and New Orleans on a longer route to the Gulf.[17][18][19]

Watershed

Map of the Mississippi River watershed

The Mississippi River has the world's fourth largest drainage basin ("watershed" or "catchment"). The basin covers more than 1,245,000 sq mi (3,220,000 km2), including all or parts of 32 U.S. states and two Canadian provinces. The drainage basin empties into the Gulf of Mexico, part of the Atlantic Ocean. The total catchment of the Mississippi River covers nearly 40% of the landmass of the continental United States. The highest point within the watershed is also the highest point of the Rocky Mountains, Mount Elbert at 14,440-foot (4,400 m).[20]
Sequence of NASA MODIS images showing the outflow of fresh water from the Mississippi (arrows) into the Gulf of Mexico (2004)

In the United States, the Mississippi River drains the majority of the area between crest of the Rocky Mountains and the crest of the Appalachian Mountains, except for various regions drained to Hudson Bay by the Red River of the North; to the Atlantic Ocean by the Great Lakes and the Saint Lawrence River; and to the Gulf of Mexico by the Rio Grande, the Alabama and Tombigbee rivers, the Chattahoochee and Appalachicola rivers, and various smaller coastal waterways along the Gulf.

The Mississippi River empties into the Gulf of Mexico about 100 miles (160 km) downstream from New Orleans. Measurements of the length of the Mississippi from Lake Itasca to the Gulf of Mexico vary somewhat, but the United States Geological Survey's number is 2,340 miles (3,770 km). The retention time from Lake Itasca to the Gulf is typically about 90 days.[21]

Outflow

The Mississippi River discharges at an annual average rate of between 200 and 700 thousand cubic feet per second (7,000–20,000 m3/s).[22] Although it is the 5th largest river in the world by volume, this flow is a mere fraction of the output of the Amazon, which moves nearly 7 million cubic feet per second (200,000 m3/s) during wet seasons. On average, the Mississippi has only 8% the flow of the Amazon River.[23]

Fresh river water flowing from the Mississippi into the Gulf of Mexico does not mix into the salt water immediately. The images from NASA's MODIS (to the right) show a large plume of fresh water, which appears as a dark ribbon against the lighter-blue surrounding waters. These images demonstrate that the plume did not mix with the surrounding sea water immediately. Instead, it stayed intact as it flowed through the Gulf of Mexico, into the Straits of Florida, and entered the Gulf Stream. The Mississippi River water rounded the tip of Florida and traveled up the southeast coast to the latitude of Georgia before finally mixing in so thoroughly with the ocean that it could no longer be detected by MODIS.

Prior to 1900, the Mississippi River transported an estimated 400 million metric tons of sediment per year from the interior of the United States to coastal Louisiana and the Gulf of Mexico. During the last two decades, this number was only 145 million metric tons per year. The reduction in sediment transported down the Mississippi River is the result of engineering modification of the Mississippi, Missouri, and Ohio rivers and their tributaries by dams, meander cutoffs, river-training structures, and bank revetments and soil erosion control programs in the areas drained by them.[24]

Course changes

Over geologic time, the Mississippi River has experienced numerous large and small changes to its main course, as well as additions, deletions, and other changes among its numerous tributaries, and the lower Mississippi River has used different pathways as its main channel to the Gulf of Mexico across the delta region.

Through a natural process known as avulsion or delta switching, the lower Mississippi River has shifted its final course to the mouth of the Gulf of Mexico every thousand years or so. This occurs because the deposits of silt and sediment begin to clog its channel, raising the river's level and causing it to eventually find a steeper, more direct route to the Gulf of Mexico. The abandoned distributaries diminish in volume and form what are known as bayous. This process has, over the past 5,000 years, caused the coastline of south Louisiana to advance toward the Gulf from 15 to 50 miles (25–80 km). The currently active delta lobe is called the Birdfoot Delta, after its shape, or the Balize Delta, after La Balize, Louisiana, the first French settlement at the mouth of the Mississippi.

Prehistoric courses

The current form of the Mississippi River basin was largely shaped by the Laurentide Ice Sheet of the most recent Ice Age. The southernmost extent of this enormous glaciation extended well into the present-day United States and Mississippi basin. When the ice sheet began to recede, hundreds of feet of rich sediment were deposited, creating the flat and fertile landscape of the Mississippi Valley.
During the melt, giant glacial rivers found drainage paths into the Mississippi watershed, creating such features as the Minnesota River, James River, and Milk River valleys. When the ice sheet completely retreated, many of these "temporary" rivers found paths to Hudson Bay or the Arctic Ocean, leaving the Mississippi Basin with many features "oversized" for the existing rivers to have carved in the same time period.

Ice sheets during the Illinoian Stage about 300,000 to 132,000 years before present, blocked the Mississippi near Rock Island, Illinois, diverting it to its present channel farther to the west, the current western border of Illinois. The Hennepin Canal roughly follows the ancient channel of the Mississippi downstream from Rock Island to Hennepin, Illinois. South of Hennepin, to Alton, Illinois, the current Illinois River follows the ancient channel used by the Mississippi River before the Illinoian Stage.[25][26]
View along the former riverbed at the Tennessee/Arkansas state line near Reverie, Tennessee (2007)

Historic course changes

In March 1876, the Mississippi suddenly changed course near the settlement of Reverie, Tennessee, leaving a small part of Tipton County, Tennessee, attached to Arkansas and separated from the rest of Tennessee by the new river channel. Since this event was an avulsion, rather than the effect of incremental erosion and deposition, the state line remains located in the old channel.[27]

New Madrid Seismic Zone

The New Madrid Seismic Zone, along the Mississippi River near New Madrid, Missouri, between Memphis and St. Louis, is related to an aulacogen (failed rift) that formed at the same time as the Gulf of Mexico. This area is still quite active seismically. Four great earthquakes in 1811 and 1812, estimated at approximately 8 on the Richter magnitude scale, had tremendous local effects in the then sparsely settled area, and were felt in many other places in the midwestern and eastern U.S. These earthquakes created Reelfoot Lake in Tennessee from the altered landscape near the river.

Cultural geography

State boundaries

The Mississippi River runs through or along 10 states, from Minnesota to Louisiana, and was used to define portions of these states' borders, with Wisconsin, Illinois, Kentucky, Tennessee, and Mississippi along the east side of the river, and Iowa, Missouri, and Arkansas along its west side.
Substantial parts of both Minnesota and Louisiana are on either side of the river, although the Mississippi defines part of the boundary of each of these states.

In all of these cases, the middle of the riverbed at the time the borders were established was used as the line to define the borders between adjacent states.[28][29] In various areas, the river has since shifted, but the state borders have not changed, still following the former bed of the Mississippi River as of their establishment, leaving several small isolated areas of one state across the new river channel, contiguous with the adjacent state. Also, due to a meander in the river, a small part of western Kentucky is contiguous with Tennessee, but isolated from the rest of its state.

Communities along the river

Metro Area Population
Minneapolis-Saint Paul 3,615,901
St. Louis 2,900,605
Memphis 1,316,100
New Orleans 1,214,932
Baton Rouge 802,484
Quad Cities, IA-IL 382,630
St. Cloud, MN 189,148
La Crosse, WI 133,365
Cape Girardeau–Jackson MO-IL 96,275
Dubuque, IA 93,653
In Minnesota, the Mississippi River runs through the Twin Cities (2007)
Community of boathouses on the Mississippi River in Winona, MN (2006)
The Mississippi River at the Chain of Rocks just north of St. Louis (2005)

Many of the communities along the Mississippi River are listed below; most have either historic significance or cultural lore connecting them to the river. They are sequenced from the source of the river to its end.

Bridge crossings

The Stone Arch Bridge, the Third Avenue Bridge and the Hennepin Avenue Bridge in Minneapolis (2004)

The first bridge across the Mississippi River was built in 1855. It spanned the river in Minneapolis, Minnesota where the current Hennepin Avenue Bridge is located.[30] No highway or railroad tunnels cross under the Mississippi River.

The first railroad bridge across the Mississippi was built in 1856. It spanned the river between the Rock Island Arsenal in Illinois and Davenport, Iowa. Steamboat captains of the day, fearful of competition from the railroads, considered the new bridge a hazard to navigation. Two weeks after the bridge opened, the steamboat Effie Afton rammed part of the bridge, catching it on fire. Legal proceedings ensued, with Abraham Lincoln defending the railroad. The lawsuit went to the Supreme Court of the United States and was eventually ruled in favor of the railroad.

Below is a general overview of selected Mississippi bridges which have notable engineering or landmark significance, with their cities or locations. They are sequenced from the Upper Mississippi's source to the Lower Mississippi's mouth.

Navigation and flood control

Towboat and barges at Memphis, Tennessee

A clear channel is needed for the barges and other vessels that make the main stem Mississippi one of the great commercial waterways of the world. The task of maintaining a navigation channel is the responsibility of the United States Army Corps of Engineers, which was established in 1802.[31] Earlier projects began as early as 1829 to remove snags, close off secondary channels and excavate rocks and sandbars.

Steamboats entered trade in the 1820s, so the period 1830 – 1850 became the golden age of steamboats. As there were few roads or rails in the lands of the Louisiana Purchase, river traffic was an ideal solution. Cotton, timber and food came down the river, as did Appalachian coal. The port of New Orleans boomed as it was the trans-shipment point to deep sea ocean vessels. As a result, the image of the twin stacked, wedding cake Mississippi steamer entered into American mythology. Steamers worked the entire route from the trickles of Montana, to the Ohio river; down the Missouri and Tennessee, to the main channel of the Mississippi. Only with the arrival of the railroads in the 1880s did steamboat traffic diminish. Steamboats remained a feature until the 1920s. Most have been superseded by pusher tugs. A few survive as icons—the Delta Queen and the River Queen for instance.

A series of 29 locks and dams on the upper Mississippi, most of which were built in the 1930s, is designed primarily to maintain a 9 feet (2.7 m) deep channel for commercial barge traffic.[32][33] The lakes formed are also used for recreational boating and fishing. The dams make the river deeper and wider but do not stop it. No flood control is intended. During periods of high flow, the gates, some of which are submersible, are completely opened and the dams simply cease to function. Below St. Louis, the Mississippi is relatively free-flowing, although it is constrained by numerous levees and directed by numerous wing dams.
Barges on the Mississippi River near Ste. Genevieve, Missouri.

19th century

Lock and Dam No. 11, north of Dubuque, Iowa (2007)

In 1829, there were surveys of the two major obstacles on the upper Mississippi, the Des Moines Rapids and the Rock Island Rapids, where the river was shallow and the riverbed was rock. The Des Moines Rapids were about 11 mi (18 km) long and just above the mouth of the Des Moines River at Keokuk, Iowa. The Rock Island Rapids were between Rock Island and Moline, Illinois. Both rapids were considered virtually impassable.

In 1848, the Illinois and Michigan Canal was built to connect the Mississippi River to Lake Michigan via the Illinois River near Peru, Illinois. The canal allowed shipping between these important waterways. In 1900, the canal was replaced by the Chicago Sanitary and Ship Canal. The second canal, in addition to shipping, also allowed Chicago to address specific health issues (typhoid fever, cholera and other waterborne diseases) by sending its waste down the Illinois and Mississippi river systems rather than polluting its water source of Lake Michigan.

The Corps of Engineers recommended the excavation of a 5 ft (1.5 m) deep channel at the Des Moines Rapids, but work did not begin until after Lieutenant Robert E. Lee endorsed the project in 1837. The Corps later also began excavating the Rock Island Rapids. By 1866, it had become evident that excavation was impractical, and it was decided to build a canal around the Des Moines Rapids. The canal opened in 1877, but the Rock Island Rapids remained an obstacle. In 1878, Congress authorized the Corps to establish a 4.5-foot (1.4 m) deep channel to be obtained by building wing dams which direct the river to a narrow channel causing it to cut a deeper channel, by closing secondary channels and by dredging. The channel project was complete when the Moline Lock, which bypassed the Rock Island Rapids, opened in 1907.

To improve navigation between St. Paul, Minnesota, and Prairie du Chien, Wisconsin, the Corps constructed several dams on lakes in the headwaters area, including Lake Winnibigoshish and Lake Pokegama. The dams, which were built beginning in the 1880s, stored spring run-off which was released during low water to help maintain channel depth.
Lock and Dam No. 15, is the largest roller dam in the world Davenport, Iowa; Rock Island, Illinois. (1990)

20th century

In 1907, Congress authorized a 6-foot (1.8 m) deep channel project on the Mississippi, which was not complete when it was abandoned in the late 1920s in favor of the 9 feet (2.7 m) deep channel project.

In 1913, construction was complete on a dam at Keokuk, Iowa, the first dam below St. Anthony Falls. Built by a private power company (Union Electric Company of St. Louis) to generate electricity (originally for Streetcars in St. Louis), the Keokuk dam was one of the largest hydro-electric plants in the world at the time. The dam also eliminated the Des Moines Rapids. Lock and Dam No. 1 was completed in Minneapolis, Minnesota in 1917. Lock and Dam No. 2, near Hastings, Minnesota was completed in 1930.

Prior to the Great Mississippi Flood of 1927, the Corps' primary strategy was to close off as many side channels as possible to increase the flow in the main river. It was thought that the river's velocity would scour off bottom sediments, deepening the river and decreasing the possibility of flooding. The 1927 flood proved this to be so wrong that communities threatened by the flood began to create their own levee breaks to relieve the force of the rising river.

The Rivers and Harbors Act of 1930 authorized the 9 feet (2.7 m) channel project, which called for a navigation channel 9 ft (2.7 m) deep and 400 ft (120 m) wide to accommodate multiple-barge tows.[34][35] This was achieved by a series of locks and dams, and by dredging. Twenty-three new locks and dams were built on the upper Mississippi in the 1930s in addition to the three already in existence.
Project design flood flow capacity for the Mississippi river in thousands of cubic feet per second.[36]
Formation of the Atchafalaya River and construction of the Old River Control Structure.

Until the 1950s, there was no dam below Lock and Dam 26 at Alton, Illinois. Chain of Rocks Lock (Lock and Dam No. 27), which consists of a low-water dam and an 8.4 mi (13.5 km) long canal, was added in 1953, just below the confluence with the Missouri River, primarily to bypass a series of rock ledges at St. Louis. It also serves to protect the St. Louis city water intakes during times of low water.

U.S. government scientists determined in the 1950s that the Mississippi River was starting to switch to the Atchafalaya River channel because of its much steeper path to the Gulf of Mexico. Eventually the Atchafalaya River would capture the Mississippi River and become its main channel to the Gulf of Mexico, leaving New Orleans on a side channel. As a result, the U.S. Congress authorized a project called the Old River Control Structure, which has prevented the Mississippi River from leaving its current channel that drains into the Gulf via New Orleans.[37]

Because the large scale of high-energy water flow threatened to damage the structure, an auxiliary flow control station was built adjacent to the standing control station. This US$300 million project was completed in 1986 by the U.S. Army Corps Of Engineers. Beginning in the 1970s, the Corps applied hydrological transport models to analyze flood flow and water quality of the Mississippi. Dam 26 at Alton, Illinois, which had structural problems, was replaced by the Mel Price Lock and Dam in 1990. The original Lock and Dam 26 was demolished.
A low-water dam deepens the pool above the Chain of Rocks Lock near St. Louis (2006)
Soldiers of the Missouri Army National Guard sandbag the River in Clarksville, Missouri, June 2008, following flooding.

21st century

The Corps now actively creates and maintains spillways and floodways to divert periodic water surges into backwater channels and lakes, as well as route part of the Mississippi's flow into the Atchafalaya Basin and from there to the Gulf of Mexico, bypassing Baton Rouge and New Orleans.
The main structures are the Birds Point-New Madrid Floodway in Missouri; the Old River Control Structure and the Morganza Spillway in Louisiana, which direct excess water down the west and east sides (respectively) of the Atchafalaya River; and the Bonnet Carré Spillway, also in Louisiana, which directs floodwaters to Lake Pontchartrain (see diagram).

Some of the pre-1927 strategy is still in use today, with the Corps actively cutting the necks of horseshoe bends, allowing the water to move faster and reducing flood heights. [38]

History

Native Americans

Monks Mound, a platform mound at the site of the Mississippian city of Cahokia.
The area of the Mississippi River basin was first settled by hunting and gathering Native American peoples and is considered one of the few independent centers of plant domestication in human history.[39] Evidence of early cultivation of sunflower, a goosefoot, a marsh elder and an indigenous squash dates to the 4th millennium BCE. The lifestyle gradually became more settled after around 1000 BCE during what is now called the Woodland period, with increasing evidence of shelter construction, pottery, weaving and other practices. A network of trade routes referred to as the Hopewell interaction sphere was active along the waterways between about 200 and 500 CE, spreading common cultural practices over the entire area between the Gulf of Mexico and the Great Lakes. A period of more isolated communities followed, and agriculture introduced from Mesoamerica based on the Three Sisters (maize, beans and squash) gradually came to dominate.
After around 800 CE there arose an advanced agricultural society today referred to as the Mississippian culture, with evidence of highly stratified complex chiefdoms and large population centers. The most prominent of these, now called Cahokia, was occupied between about 600 and 1400 CE[40] and at its peak numbered between 8,000 and 40,000 inhabitants, larger than London, England of that time. At the time of first contact with Europeans, Cahokia and many other
Mississippian cities had dispersed, and archaeological finds attest to increased social stress.[41][42][43]

Modern American Indian nations inhabiting the Mississippi basin include Cheyenne, Sioux, Ojibwe, Potawatomi, Ho-Chunk, Fox, Kickapoo, Tamaroa, Moingwena, Quapaw and Chickasaw.

The word Mississippi itself comes from Messipi, the French rendering of the Anishinaabe (Ojibwe or Algonquin) name for the river, Misi-ziibi (Great River).[44][45] The Ojibwe called Lake Itasca Omashkoozo-zaaga'igan (Elk Lake) and the river flowing out of it Omashkoozo-ziibi (Elk River). After flowing into Lake Bemidji, the Ojibwe called the river Bemijigamaag-ziibi (River from the Traversing Lake). After flowing into Cass Lake, the name of the river changes to Gaa-miskwaawaakokaag-ziibi (Red Cedar River) and then out of Lake Winnibigoshish as Wiinibiigoonzhish-ziibi (Miserable Wretched Dirty Water River), Gichi-ziibi (Big River) after the confluence with the Leech Lake River, then finally as Misi-ziibi (Great River) after the confluence with the Crow Wing River.[46] After the expeditions by Giacomo Beltrami and Henry Schoolcraft, the longest stream above the juncture of the Crow Wing River and Gichi-ziibi was named "Mississippi River". The Mississippi River Band of Chippewa Indians, known as the Gichi-ziibiwininiwag, are named after the stretch of the Mississippi River known as the Gichi-ziibi. The Cheyenne, one of the earliest inhabitants of the upper Mississippi River, called it the Máʼxe-éʼometaaʼe (Big Greasy River) in the Cheyenne language. The Arapaho name for the river is Beesniicíe.[47] The Pawnee name is Kickaátit.[48]

European exploration

Ca. 1681 map of Marquette and Jolliet's 1673 expedition.
Discovery of the Mississippi by De Soto A.D. 1541 (1847–53) by William Henry Powell depicts DeSoto seeing the River for the first time.

On May 8, 1541, Spanish explorer Hernando de Soto became the first recorded European to reach the Mississippi River, which he called Río del Espíritu Santo ("River of the Holy Spirit"), in the area of what is now Mississippi. In Spanish, the river is called Río Mississippi.[49]

French explorers Louis Jolliet and Jacques Marquette began exploring the Mississippi in the 17th century. Marquette traveled with a Sioux Indian who named it Ne Tongo ("Big river" in Sioux language) in 1673. Marquette proposed calling it the River of the Immaculate Conception.

When Louis Jolliet explored the Mississippi Valley in the 17th century, natives guided him to a quicker way to return to French Canada via the Illinois River. When he found the Chicago Portage, he remarked that a canal of "only half a league" (less than 2 miles (3.2 km), 3 km) would join the Mississippi and the Great Lakes.[50] In 1848, the continental divide separating the waters of the Great Lakes and the Mississippi Valley was breached by the Illinois and Michigan canal via the Chicago River.[51] This both accelerated the development, and forever changed the ecology of the Mississippi Valley and the Great Lakes.

In 1682, René-Robert Cavelier, Sieur de La Salle and Henri de Tonti claimed the entire Mississippi River Valley for France, calling the river Colbert River after Jean-Baptiste Colbert and the region La Louisiane, for King Louis XIV. On March 2, 1699, Pierre Le Moyne d'Iberville rediscovered the mouth of the Mississippi, following the death of La Salle.[52] The French built the small fort of La Balise there to control passage.[53]

In 1718, about 100 miles (160 km) upriver, New Orleans was established along the river crescent by Jean-Baptiste Le Moyne, Sieur de Bienville, with construction patterned after the 1711 resettlement on Mobile Bay of Mobile, the capital of French Louisiana at the time.

Colonization


Following Britain's victory in the Seven Years War the Mississippi became the border between the British and Spanish Empires. The Treaty of Paris (1763) gave Great Britain rights to all land east of the Mississippi and Spain rights to land west of the Mississippi. Spain also ceded Florida to Britain to regain Cuba, which the British occupied during the war. Britain then divided the territory into East and West Florida.

Article 8 of the Treaty of Paris (1783) states, "The navigation of the river Mississippi, from its source to the ocean, shall forever remain free and open to the subjects of Great Britain and the citizens of the United States". With this treaty, which ended the American Revolutionary War, Britain also ceded West Florida back to Spain to regain the Bahamas, which Spain had occupied during the war. In 1800, under duress from Napoleon of France, Spain ceded an undefined portion of West Florida to France. When France then sold the Louisiana Territory to the US in 1803, a dispute arose again between Spain and the U.S. on which parts of West Florida exactly had Spain ceded to France, which would in turn decide which parts of West Florida were now U.S. property versus Spanish property. These aspirations ended when Spain was pressured into signing Pinckney's Treaty in 1795.

France reacquired 'Louisiana' from Spain in the secret Treaty of San Ildefonso in 1800. The United States then bought the territory from France in the Louisiana Purchase of 1803. In 1815, the U.S. defeated Britain at the Battle of New Orleans, part of the War of 1812, securing American control of the river. So many settlers traveled westward through the Mississippi river basin, as well as settled in it, that Zadok Cramer wrote a guide book called The Navigator, detailing the features and dangers and navigable waterways of the area. It was so popular that he updated and expanded it through 12 editions over a period of 25 years.
Shifting sand bars made early navigation difficult.

The colonization of the area was barely slowed by the three earthquakes in 1811 and 1812, estimated at approximately 8 on the Richter magnitude scale, that were centered near New Madrid, Missouri.

Steamboat era

Mark Twain's book, Life on the Mississippi, covered the steamboat commerce which took place from 1830 to 1870 on the river before more modern ships replaced the steamer. The book was published first in serial form in Harper's Weekly in seven parts in 1875. The full version, including a passage from the then unfinished Adventures of Huckleberry Finn and works from other authors, was published by James R. Osgood & Company in 1885.
The first steamboat to travel the full length of the Lower Mississippi from the Ohio River to New Orleans was the New Orleans in December 1811. Its maiden voyage occurred during the series of New Madrid earthquakes in 1811–12. Steamboat transport remained a viable industry, both in terms of passengers and freight until the end of the first decade of the 20th century. Among the several Mississippi River system steamboat companies was the noted Anchor Line, which, from 1859 to 1898, operated a luxurious fleet of steamers between St. Louis and New Orleans.

Civil War

Battle of Vicksburg (ca. 1888)

Control of the river was a strategic objective of both sides in the American Civil War. In 1862 Union forces coming down the river successfully cleared Confederate defenses at Island Number 10 and Memphis, Tennessee, while Naval forces coming upriver from the Gulf of Mexico captured New Orleans, Louisiana. The remaining major Confederate stronghold was on the heights overlooking the river at Vicksburg, Mississippi, and the Union's Vicksburg Campaign (December 1862 to July 1863), and the fall of Port Hudson, completed control of the lower Mississippi River. The Union victory ending the Siege of Vicksburg on July 4, 1863 was pivotal to the Union's final victory of the Civil War.

20th and 21st centuries

The "Big Freeze" of 1918/19 blocked river traffic north of Memphis, Tennessee, preventing transportation of coal from southern Illinois. This resulted in widespread shortages, high prices, and rationing of coal in January and February.[54]
In the spring of 1927, the river broke out of its banks in 145 places, during the Great Mississippi Flood of 1927 and inundated 27,000 sq mi (70,000 km2) to a depth of up to 30 ft (9.1 m).

In 1962 and 1963, industrial accidents spilled 3.5 million gallons of soybean oil into the Mississippi and Minnesota Rivers. The oil covered the Mississippi River from St. Paul to Lake Pepin, creating an ecological disaster and a demand to control water pollution.[55]

On October 20, 1976, the automobile ferry, MV George Prince, was struck by a ship traveling upstream as the ferry attempted to cross from Destrehan, Louisiana, to Luling, Louisiana. Seventy-eight passengers and crew died; only eighteen survived the accident.

In 1988, record low water levels provided an opportunity and obligation to examine the climax of the wooden-hulled age. The Mississippi fell to 10 feet (3.0 m) below zero on the Memphis gauge. Water craft remains were exposed in an area of 4.5 acres (18,000 m2) on the bottom of the Mississippi River at West Memphis, Arkansas. They dated to the late 19th to early 20th centuries. The State of Arkansas, the Arkansas Archeological Survey, and the Arkansas Archeological Society responded with a two-month data recovery effort. The fieldwork received national media attention as good news in the middle of a drought.[56]

The Great Flood of 1993 was another significant flood, primarily affecting the Mississippi above its confluence with the Ohio River at Cairo, Illinois.

Two portions of the Mississippi were designated as American Heritage Rivers in 1997: the lower portion around Louisiana and Tennessee, and the upper portion around Iowa, Illinois, Minnesota and Missouri.
Campsite at the river in Arkansas

In 2002, Slovenian long-distance swimmer Martin Strel swam the entire length of the river, from Minnesota to Louisiana, over the course of 68 days.

In 2005, the Source to Sea Expedition[57] paddled the Mississippi and Atchafalaya Rivers to benefit the Audubon Society's Upper Mississippi River Campaign.[58][59]

On August 1, 2007, the I-35W Mississippi River bridge in Minneapolis collapsed during the evening rush hour.

Extensive flooding in April, May, and June 2011 was compared to the Great Mississippi Flood of 1927 and the Great Mississippi and Missouri Rivers Flood of 1993.

Recreation

Great River Road in Wisconsin near Lake Pepin (2005)

The sport of water skiing was invented on the river in a wide region between Minnesota and Wisconsin known as Lake Pepin.[60] Ralph Samuelson of Lake City, Minnesota, created and refined his skiing technique in late June and early July 1922. He later performed the first water ski jump in 1925 and was pulled along at 80 mph (130 km/h) by a Curtiss flying boat later that year.[60]

There are seven National Park Service sites along the Mississippi River. The Mississippi National River and Recreation Area is the National Park Service site dedicated to protecting and interpreting the Mississippi River itself. The other six National Park Service sites along the river are (listed from north to south):

Cultural references

Literature

  • William Faulkner uses the Mississippi River and Delta as the setting for many hunts throughout his novels. It has been proposed that in Faulkner's famous story, The Bear, young Ike first begins his transformation into a man, thus relinquishing his birthright to land in Yoknapatawpha County through his realizations found within the woods surrounding the Mississippi River.
  • Many of the works of Mark Twain deal with or take place near the Mississippi River. One of his first major works, Life on the Mississippi, is in part a history of the river, in part a memoir of Twain's experiences on the river, and a collection of tales that either take place on or are associated with the river. The river was noted for the number of bandits which called its islands and shores home, including John Murrell who was a well-known murderer, horse stealer and slave "re-trader". His notoriety was such that author Twain devoted an entire chapter to him in Life on the Mississippi, and Murrell was rumored to have an island headquarters on the river at Island 37. Twain's most famous work, Adventures of Huckleberry Finn, is largely a journey down the river. The novel works as an episodic meditation on American culture with the river having multiple different meanings including independence, escape, freedom, and adventure.
  • Herman Melville's novel The Confidence-Man portrayed a Canterbury Tales-style group of steamboat passengers whose interlocking stories are told as they travel down the Mississippi River. The novel is written both as cultural satire and a metaphysical treatise. Like Huckleberry Finn, it uses the Mississippi River as a metaphor for the larger aspects of American and human identity that unify the otherwise disparate characters. The river's fluidity is reflected by the often shifting personalities and identities of Melville's "confidence man".
  • Much of Edna Ferber's 1926 novel Show Boat takes place on the Mississippi River. The novel is the basis for the celebrated 1927 musical play by Jerome Kern and Oscar Hammerstein II.

Music

On The Mississippi, music sheet cover for a 1912 song

Computational complexity theory

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