The Mississippi River is the chief river of the largest river 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 meandersslowly southwards for 2,530 miles (4,070 km)[5] to the Mississippi River Delta at the Gulf of Mexico. Sony VAIO PCG-3B1M Battery
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 cuts through the states of Minnesota, Wisconsin, Iowa, Illinois, Missouri,Kentucky, Tennessee, Arkansas, Mississippi, and Louisiana. Sony VAIO PCG-3C1T Battery
Native Americans 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. Sony VAIO PCG-3D1M Battery
The river served first as barrier – forming borders for New Spain, New France, and the early United States – then as 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 pioneers partaking in the western expansion of the United States. Sony VAIO PCG-3G2M Battery
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 this very importance as a route of trade and travel, not least to the Confederacy. Sony VAIO PCG-5R1M Battery
Because of substantial growth of cities and the larger ships and barges that have supplanted riverboats, the decades following the 1900s saw massiveengineering works applied to the river system, such as the often in-combination construction of levees, locks and dams. Sony VAIO PCG-7141M Battery
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; Sony VAIO PCG-7143M Battery
a course change would prove disastrous to seaports such as New Orleans. A system of dikes and gates has, so far, held the Mississippi at bay but, due to fluvial processes, the shift becomes more likely each year.
The word Mississippi itself comes from Messipi, the French rendering of the Anishinaabe (Ojibwe or Algonquin) name for the river, Misi-ziibi (Great River). Sony VAIO PCG-7151M Battery
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. Sony VAIO PCG-7154M Battery
Using the largest-branch criterion, the Ohio would be the main branch of the Lower Mississippi, not the Middle and Upper Mississippi. Using the longest-branch criterion, the Middle Mississippi-Missouri-Jefferson-Beaverhead-Red Rock-Hellroaring Creek River would be the main branch. Sony VAIO PCG-7162M Battery
In either of these cases, despite its name, the Upper Mississippi from Lake Itasca, Minnesota to St. Louis, would not be part of the more significant branch flowing between St. Louis and the Gulf of Mexico.
While the Missouri River, flowing from the confluence of the Jefferson, Sony VAIO PCG-7181M Battery
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, Sony VAIO PCG-41112M Battery
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) is exceeded only by the Nile, the Amazon,[6] and perhaps the Yangtze Riveramong the longest rivers in the world. The source of this waterway is at Brower's Spring, Sony VAIO PCG-7153M Battery
8,800 feet (2,700 m) above sea level in southwestern Montana, along the Continental Divide outside Yellowstone National Park.
The unifying name "Great American River" has been suggested for this multiple named waterway. Sony VAIO PCG-71312M Battery
However, the names "Mississippi River" for the water course from Minnesota to the Gulf of Mexico, "Missouri River" for its major western portion, and "Ohio River" for its major eastern portion are so well established that neither reassignment of names nor creation of novel names can be seriously considered as replacements for current usage. Sony VAIO PCG-7144M Battery
Furthermore, the north-south course of the waterway commonly known as 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", Sony VAIO PCG-7191L Battery
used for example in the name of the 1898 Trans-Mississippi Exposition held in Omaha, Nebraska.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. Sony VAIO PCG-3C1M Battery
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. Sony VAIO PCG-3F1M Battery
River course
The Mississippi River is divided into the Upper Mississippi, the Middle Mississippi, and the Lower Mississippi, with the Upper Mississippi upriver of its confluence with the Missouri River, the Middle Mississippi from there downriver to the Ohio River, and the Lower Mississippi from there downriver to the Gulf of Mexico. Sony VAIO PCG-3H1M Battery
The Mississippi River is known as the Upper Mississippi from its headwaters to its confluence with the Missouri River at St. Louis, Missouri. The Upper Mississippi is divided into two sections:The headwaters, 493 miles (793 km), from the source to Saint Anthony Falls in Minneapolis, Minnesota.Sony VAIO PCG-3J1M Battery
A navigable channel, formed by a series of man-made lakes between Minneapolis and St. Louis, Missouri, 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. Sony VAIO PCG-8141M Battery
The name "Itasca" is 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).[8] However, the lake is in turn fed by a number of smaller streams, of which one might be selected as the river's ultimate source.
From its origin at Lake Itasca to St. Louis, Missouri, the waterway's flow is moderated by 43 dams. Sony VAIO PCG-8161M Battery
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. Sony VAIO PCG-3C2M Battery
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. Sony VAIO PCG-5N2M Battery
The head of navigation on the Mississippi is the Coon Rapids Dam in Coon Rapids, Minnesota. Before its construction 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. Sony VAIO PCG-5P1M Battery
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. Sony VAIO PCG-5S1M Battery
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, nearGrand Rapids, Minnesota, over 7 miles (11 km) across. Sony VAIO PCG-9Z1M Battery
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. Sony VAIO PCG-7171M Battery
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. Sony VAIO PCG-7186M Battery
The Upper Mississippi River is joined by the Minnesota River at Fort Snelling in the Twin Cities; the St. Croix River nearPrescott, Wisconsin; the Cannon River near Red Wing, Minnesota; the Black, La Crosse, and Root rivers in La Crosse, Wisconsin; the Wisconsin River at Prairie du Chien, Wisconsin; Sony VAIO PCG-81112M Battery
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 theWapsipinicon River in Iowa, and the Big Muddy River and Illinois River. Sony VAIO PCG-31311M Battery
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. Sony VAIO PCG-8152M Battery
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).
The Mississippi River is known as the Middle Mississippi from the Upper Mississippi River's confluence with the Missouri River at St. Louis, Sony VAIO PCG-31111M Battery
Missouri, for 190 miles (310 km) to its confluence with the Ohio River at Cairo, Illinois.[11][12]
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). Sony VAIO PCG-61111M Battery
At its confluence with the Ohio River, the Middle Mississippi is 315 feet (96 m) above sea level. Apart from theMissouri River, and the Kaskaskia River in Illinois, no major tributaries enter the Middle Mississippi River.
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