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### River and Basin Facts The Upper Mississippi River System is the only waterbody in the nation that has been recognized by Congress as a "nationally significant ecosystem and a nationally significant commercial navigation system." (Section 1103 of the Water Resources Development Act of 1986, P.L. 99-662)



### The River The Upper Mississippi River flows roughly 1,300 miles, from Lake Itasca in northern Minnesota to the confluence with the Ohio River at the southern tip of Illinois, over half of the length of the entire Mississippi River. Approximately 850 miles of the river, extending from Minneapolis-St. Paul to the Ohio River, is commercially navigable. On the northern 670 miles, this is made possible by a series of 29 locks and dams, most built in the 1930s, which create a stairway of water. In addition, the river is dredged to maintain a minimum main channel depth of 9 feet. The Illinois River connects the Mississippi River to the Great Lakes. Together, the Upper Mississippi River; Illinois River; and small portions of the Minnesota, St. Croix, Black, and Kaskaskia Rivers provide a 1200-mile commercially navigable river network in the upper Midwest. In 2000, barges transported 122 million tons of commodities on the Upper Mississippi River, over half of which was grain for world export. Approximately 52 percent of the nation’s corn and 41 percent of the nation’s soybean exports are carried on the Upper Mississippi River System, which includes the Illinois River. Along the Minnesota-Wisconsin border, the river and its floodplain are between 1 and 3 miles wide. However, in the alluvial lowlands south of St. Louis, the floodplain is roughly 50 miles wide. The average annual discharge on the Upper Mississippi River increases from 9,180 cubic feet per second (cfs) near St. Paul, Minnesota to 204,800 cfs at Thebes, Illinois. Flood control levees protect about 3 percent of the floodplain north of Rock Island, Illinois; 53 percent of the floodplain in the middle reach between Rock Island and St. Louis; and 83 percent of the floodplain south of St. Louis. There are 3 national refuges along the Upper Mississippi River, totaling over 285,000 acres. They include the Upper Mississippi River National Wildlife and Fish Refuge, Trempealeau National Wildlife Refuge, and Mark Twain National Wildlife Refuge. The states manage another 140,000 acres of refuge lands along the river. Recreational visits to the Upper Mississippi River region exceeded 11 million trips in 2000, more than most national parks, including Yellowstone. There are approximately 500 boat access points and marinas along the Upper Mississippi River between the facts http://www.umrba.org/facts.htm

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The river supports more than 127 species of fish and 30 species of freshwater mussels. Nearly 300 species of birds migrate through the river valley in spring and fall. The Mississippi Flyway is used by more than 40 percent of the migratory waterfowl traversing the U.S. Over 7 billion gallons of water are withdrawn from surface water sources each day in the 60 counties that border the navigable Upper Mississippi River. Over 80 percent of this water is used as cooling water for energy production and thus returned to rivers and streams. There are 29 power plants that use water from the 1,300 mile long Upper Mississippi River. From St. Cloud, Minnesota in the north to Cape Girardeau, Missouri in the south, the Upper Mississippi River provides water to 23 public water suppliers serving a combined population of approximately 2.8 million people. Approximately 278 facilities discharge wastewater to the Upper Mississippi River, including industrial facilities and municipal sewage treatment plants.



### The Basin The Upper Mississippi River Basin drains approximately 189,000 square miles, including large parts of the states of Illinois, Iowa, Minnesota, Missouri, and Wisconsin. Small portions of Indiana, Michigan, and South Dakota are also within the basin. More than 30 million people live in the basin. Nearly 80 percent of the population lives in urban areas such as Minneapolis-St. Paul, Minnesota; St. Louis, Missouri; Chicago, Illinois; the Quad Cities, Illinois and Iowa; Des Moines, Iowa; La Crosse, Wisconsin; and Peoria, Illinois. There are 12 major tributaries to the Upper Mississippi River, including the Missouri, Illinois, Wisconsin, and Iowa Rivers. The basin has 30,700 miles of streams. Over 60 percent of the basin is cropland or pasture. Major cash crops include corn and soybeans. There are over 3,000 reservoirs in the basin. The flood storage volume of 40 million acre-feet would take over 3 months to flow past St. Louis at average discharges.

Sources: U.S. Geological Survey, Ecological Status and Trends of the Upper Mississippi River System , April 1999. U.S. Army Corps of Engineers, Interim Report for the Restructured Upper Mississippi River-Illinois Waterway System Navigation Feasibility Study, July 2002. Industrial Economics, Incorporated, Economic Profile of the Upper Mississippi River Region , March 1999. Upper Mississippi River Basin Association, database prepared for the U.S. Environmental Protection Agency's Region 5 Inland Sensitivity Mapping Project, January 2003. facts http://www.umrba.org/facts.htm

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