The Mississippi River

The Mississippi River is the largest river system and second longest river in North America. The Missouri of United States is the longest river in North America. The Mississippi River is about 3,779 km (2,348 mi) long. Its triangular drainage area, covering about 40% of the country and including all or part of 31 states, is approximately 3,250,000 sq km (1,250,000 sq mi), the third largest in the world. The word, Mississippi probably comes from a combination of Chippewa words (mici and zibi) meaning "great river" or "great water." It was first written as "Michi Sepe" by Lieutenant Henri de Tonti traveling with the explorer La Salle. The Mississippi River is originates at an elevation of 446 m (1,463 ft) at Lake Itasca, Minnesota, and flows slowly southwards in sweeping meanders, terminating 95 miles (153 km) by river below New Orleans, where it begins to flow to the Gulf of Mexico. Along with its major tributary, the Missouri River, the river drains all or parts of 31 U.S. states stretching from the Rocky Mountains in the west to the Appalachian Mountains in the east to the Canada–US border on the north, including most of the Great Plains, and is the fourth longest river in the world and the tenth most powerful river in the world. . After this confluence, the Mississippi is fringed by 60-90-m-high (200-300-ft) bluffs on both sides.

The current form of the Mississippi River basin was largely shaped by an ice Sheet. This Ice Sheet is of the most recent Ice Age and the Ice Sheet is called as Laurentide Ice Sheet. The southernmost extent of this enormous glaciation extended well into the present-day United States and Mississippi basin. The flat and fertile landscape of the Mississippi Valley is formed due to the receding of ice sheet of Laurentide Ice Sheet and due to receding of ice sheet hundreds of feet of rich sediment were deposited which created the 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. The Mississippi River Delta has shifted and changed constantly since the formation of the river. Here it should be mentioned that the construction of dams on the river has greatly reduced the flow of sediment to the delta. In recent years, the Mississippi's mouth has shown a steady shift towards the Atchafalaya River channel, but because of floodworks at the river's mouth, this change of course—which would be catastrophic for seaports at the river mouth—has been held at bay.

Between Minneapolis and Saint Louis, Minnesota, the most important tributaries which  join with the Mississippi River are the Illioois, Chippewa, Black, Wisconsin, Saint Croix, Iowa, Des Moines, and Rock rivers, some of which drain the nation's most fertile agricultural areas. The Missouri River, draining the Great Plains to the west, joins the Mississippi at Saint Louis. At Cairo, Ill., the Mississippi is joined from the east by the Ohio River.

Geography

After the originating of the Mississippi River at an elevation of 446 m (1,463 ft) at Lake Itasca, Minnesota, the flow of the Mississippi River is moderated by 43 no’s of dams. Fourteen of these dams are located above Minneapolis in the headwaters region and serve multiple purposes including Hydro Electric Power generation and recreation. On the other hand the remaining 29 dams are located at downstream (downtown Minneapolis) of the Mississippi River and they all contain locks and were constructed to permit commercial navigation of the upper river. Anyway together all these 43 dams significantly shape the geography and influence the ecology of the upper river.

From its origin at Lake Itasca to St. Louis, Missouri, the flow of the Mississippi River 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 permit 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.

The Mississippi is further controlled by thousands of wing dikes just below Saint Paul, Minnesota and continuing throughout the upper and lower river. The wings dikes are moderate the river's flow in order to maintain an open navigation channel and prevent the river from eroding its banks.

The Ohio River is the largest tributary among all the tributaries of The Mississippi River as by the amount of water volume. Measured by water volume, the largest of all Mississippi tributaries is the Ohio River. At the confluence of the river, the Ohio River is even bigger than the Mississippi River itself (long term mean discharge of the Ohio at Cairo: 281,500 cu ft/s (7,970 m³/s); long term mean discharge of the Mississippi at Thebes: 208,200 cu ft/s (5,900 m³/s)) and, thus, is hydrologically the main stream of the whole river system, also including the Allegheny River further upstream.

The Mississippi River is divided into two parts; one as the upper Mississippi and the other is as the lower Mississippi.

Upper Mississippi River

The Mississippi River from its source to the confluence of the Ohio River at the southern tip of the state of Illinois is called The Upper Mississippi River. Again the Upper Mississippi River is further divided into three sections:

1. The headwaters, 493 miles (793 km), from the source to Saint Anthony Falls
2. A series of man-made lakes between Minneapolis, Minnesota and St. Louis, Missouri, 664 miles (1,069 km)
3. The middle Mississippi, 190 miles (310 km), a relatively free-flowing river from the confluence with the Missouri River at St. Louis, Missouri to the confluence of the Ohio River.

Lower Mississippi River

The Mississippi River from the confluence of the Ohio River to its mouth at the Gulf of Mexico is called the Lower Mississippi River.

The major tributaries of the Mississippi River are Minnesota River,  St. Croix River, Black River , La Crosse River, Root River (Minnesota), Wisconsin River, Rock River,  Iowa River , Skunk River, Des Moines River, Illinois River, Missouri River, White River, Arkansas Post;  Yazoo River, Vicksburg, Mississippi, Red River, Atchafalaya River

The Mississippi River and its valley also support many kinds of animals and plants including freshwater fishes, birds, deer, raccoons, otters, mink, and a variety of forest trees. At the last it should be mentioned that the pollution from agriculture and industry seriously threaten the life of the Mississippi. We all should awake up before it grabs the great Mississippi River.