New Jersey explorer: Mississippi

Mississippi, river, principal river of the United States, c.2,350 mi (3,780 km) long, exceeded in length only by the Misoury, the chief of its numerous tributaries. The combined Missouri-Mississippi system (from the Missouri's headwaters in the Rocky Mts. to the mouth of the Mississippi) is c.3,740 mi (6,020 km) long and ranks as the world's third longest river system after the Nile and the Amazon. With its tributaries, the Mississippi drains c.1,231,000 sq mi (3,188,290 sq km) of the central United States, including all or part of 31 states and c.13,000 sq mi (33,670 sq km) of Alberta and Saskatchewan in Canada. Cotton and rice are important crops in the lower Mississippi valley; sugarcane is raised in the delta. The Mississippi is abundant in freshwater fish; shrimp are taken from the briny delta waters. The delta also yields sulfur, oil, and gas.
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Course and Navigation

The Mississippi River rises in small streams that feed Lake Italaska (alt. 1,463 ft/446 m) in N Minnesota and flows generally south to enter the Gulf of Mexico through a huge delta in SE Louisiana. A major economic waterway, the river is navigable from the sediment-free channel maintained through South Pass in the delta to the Falls of St. Anthony in Minneapolis, with canals circumventing the rapids near Rock Island, Ill., and Keokuk, Iowa. For the low-water months of July, August, and September, there is a 45-ft (13.7-m) channel navigable by oceangoing vessels from Head of the Passes to Baton Rouge, La., and a 9-ft (2.7-m) channel from Baton Rouge deep enough for barges and towboats to Minneapolis. The Mississippi connects with the Intracoastal Waterway in the south and with the Great Lakes–St. Lawrence Seaway system in the north by way of the Illinois Waterway.

Along the river's upper course shipping is interrupted by ice from December to March; thick, hazardous fogs frequently settle on the cold waters of the unfrozen sections during warm spells from December to May. In its upper course the river is controlled by numerous dams and falls c.700 ft (210 m) in the 513-mi (826-km) stretch from Lake Itasca to Minneapolis and then falls c.490 ft (150 m) in 856 mi (1,378 km) from Minneapolis to Cairo, Ill. The Mississippi River receives the Missouri River 17 mi (27 km) N of St. Louis and expands to a width of c.3,500 ft (1,070 m); it swells to c.4,500 ft (1,370 m) at Cairo, where it receives the Ohio River.

The lower Mississippi meanders in great loops across a broad alluvial plain (25–125 mi/40–201 km wide) that stretches from Cape Girardeau, Mo., to the delta region S of Natchez, Miss. The plain is marked with oxbow lakes and marshes that are remnants of the river's former channels. Natural levees, built up from sediment carried and deposited in times of flood, border the river for much of its length; sediment has also been deposited on the riverbed, so that in places the surface of the Mississippi is above that of the surrounding plain, as evidenced by the St. Francis, Black, Yazoo, and Tensas river basins. Breaks in the levees frequently flood the fertile bottomlands of these and other low-lying areas of the plain.

Role of the river

Electricity production on the river

the Mississippi River allowed access to the Southeast from the gulf coast, and was tremendously important in allowing the colonization of that part of the United States.
In addition, I would say that access to the river encouraged agriculture in the region, since without the Mississippi and its tributaries, there would have been no easy way to transport bulk commodities from the plantations to the end markets in the Northeast and in Europe.
Finally, the ease of transport also helped foster the slave trade. Transporting slaves overland would have been a much more difficult and expensive proposition than simply loading them on a boat and opening the hatch again at the destination, requiring much more manpower to keep control and opening the slavetraders to a much higher possibility of slave revolts or other mishaps.
The Mississippi river was critical in the development of southeast, and remains so even today. In later times, the Mississippi river and its tributaries allowed for the Tennessee Valley Authority to develop the system of dams that powers much of the region today, and it remains an important transport route for bulk cargo.

Also, the river gives an opportunity to produce electricity.
http://answers.ask.com/Science/Nature/why_is_the_mississippi_river_important

Role in civil war

The control of the river was of strategic importance to both sides during the war. The North had set up a blocade in some major southern cities. To fully contain them they needed to also have control of the river. Roads at this time were not very well maintained. There were some railways, but these were limited. River travel was still the quickest and easiest way to travel during this time. Large amounts of troops and supplies could be transported in this way. The Mississippi also has many tributaries. Who ever controlled it would in turn control these lesser waterways.