The Mississippi River is the second longest river in the United States, with a length of 2,320 mi (3,734 km) from its source in Lake Itasca in Minnesota to its mouth in Gulf of Mexico. The longest is its tributary the Missouri River measuring 2,341 mi (3,767 km).
The Mississippi River is part of the Jefferson-Missouri-Mississippi river system, which is the largest river system in North America and among the largest in the world: by length (3,900 mi or 6,275 km), it is the fourth longest, and by average discharge of 572,000 cu ft/s (16,200 m³/s), it is the tenth largest.
The longest of the many long Mississippi tributaries is the Missouri River with the Arkansas River as second longest. Measured by water volume, the largest of all Mississippi tributaries is the Ohio River.
The widest point of the Mississippi River is Lake Onalaska, near La Crosse, Wisconsin, where the river is over 4 mi (6.4 km) wide. Since Lake Onalaska was created by Lock and Dam No. 7, Lake Pepin is historically the widest natural spot at more than two miles (3 km) wide. These areas however are reservoir rather than free flowing river. In areas where the Mississippi is a real river, it exceeds one mile (1.6 km) in width in several places in its lower course.
The river is divided into the upper Mississippi, from its source south to the Ohio River, and the lower Mississippi, from the Ohio to its mouth near New Orleans, Louisiana.
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 ft (2.7 m) deep channel for commercial barge traffic. 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, Missouri, the Mississippi is relatively free-flowing, although it is constrained by numerous levees and directed by numerous wing dams.
The Mississippi River runs through 10 states and was used to define portions of these states' borders. The middle of the riverbed at the time the borders were established was the line to define the borders between states. The river has since shifted, but the state borders of Wisconsin, Iowa, Illinois, Missouri, Kentucky, Arkansas, Tennessee, and Mississippi have not changed; they still follow the former bed of the Mississippi River as of their establishment.
The upper Mississippi is divided into three sections: the headwaters, from the source to Saint Anthony Falls, a series of man-made lakes between Minneapolis and St. Louis, Missouri, and the middle Mississippi, a relatively free-flowing river downstream of the confluence with the Missouri River at St. Louis.
East St. Louis lies in the heart of the American Bottoms -the flood plain on the east side of the Mississippi River opposite St. Louis.
If there ever was a "fishin' hole" crying for more anglers, it would be the mighty Mississippi River which forms the western border of Illinois and glides along the entire length of the state.
You name it and the "Father of Waters" has it. Walleyes, northern pike and sauger swim in the northern stretches. Crappies, plump bluegills, largemouth bass and bullheads are caught in the myriad of backwater lakes and sloughs. Channel catfish are found virtually everywhere, and white bass fisheries explode at times.
Essentially, the river changes from a walleye fishery in the north to a catfish hotspot in the south. The river widens and becomes more turbid the farther south it goes, especially below St. Louis, Mo., where the Missouri River joins it.
Launching ramps are found in virtually every town located along the river in the 14 navigation pools and at state and federal public use areas. Access is very limited in the stretch below Alton. Motels also are located in larger towns along the stream.
The walleye and sauger fishery extends about as far south as Lock 21 at Quincy, but pools north of that are considered hotspots. Wing dams in Pool 12 in Jo Daviess County are excellent spots as is the tailwater below Lock and Dam 12 at Bellevue, Iowa. Lock and Dam 17 at New Boston also is heavily fished for these species.
Coves, submerged timber, brush.