Rivers on the boundary
- Mississippi River (Illinois, Wisconsin)
- Missouri River (Nebraska)
- Big Sioux River (South Dakota)
- Des Moines River (20 mi or 32 km of the boundary with Missouri)
The following is a list of rivers and creeks in Iowa. The rivers are listed by multiple arrangements:
This list is arranged by drainage basin, with respective tributaries indented under each larger stream's name. All Iowa rivers are part of the Mississippi River Watershed, which in Iowa consists of the Upper Mississippi River Drainage Basin and the Missouri River Drainage Basin.
Upper Mississippi River drainage basin
| Missouri River drainage basin
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The Mississippi River is the second-longest river and chief river of the second-largest drainage system in North America, second only to the Hudson Bay drainage system. From its traditional source of Lake Itasca in northern Minnesota, it flows generally south for 2,340 miles (3,770 km) to the Mississippi River Delta in the Gulf of Mexico. With its many tributaries, the Mississippi's watershed drains all or parts of 32 U.S. states and two Canadian provinces between the Rocky and Appalachian mountains. The main stem is entirely within the United States; the total drainage basin is 1,151,000 sq mi (2,980,000 km2), of which only about one percent is in Canada. The Mississippi ranks as the thirteenth-largest river by discharge in the world. The river either borders or passes through the states of Minnesota, Wisconsin, Iowa, Illinois, Missouri, Kentucky, Tennessee, Arkansas, Mississippi, and Louisiana.
The Missouri River is the longest river in the United States. Rising in the Rocky Mountains of the Eastern Centennial Mountains of Southwestern Montana, the Missouri flows east and south for 2,341 miles (3,767 km) before entering the Mississippi River north of St. Louis, Missouri. The river drains a sparsely populated, semi-arid watershed of more than 500,000 square miles (1,300,000 km2), which includes parts of ten U.S. states and two Canadian provinces. Although a tributary of the Mississippi, the Missouri River is much longer and carries a comparable volume of water. When combined with the lower Mississippi River, it forms the world's fourth longest river system.
The Kansas River, also known as the Kaw, is a river in northeastern Kansas in the United States. It is the southwesternmost part of the Missouri River drainage, which is in turn the northwesternmost portion of the extensive Mississippi River drainage. Its two names both come from the Kanza (Kaw) people who once inhabited the area; Kansas was one of the anglicizations of the French transcription Cansez of the original kką:ze. The city of Kansas City, Missouri, was named for the river, as was later the state of Kansas.
The Platte River is a major river in the State of Nebraska. It is about 310 mi (500 km) long; measured to its farthest source via its tributary, the North Platte River, it flows for over 1,050 miles (1,690 km). The Platte River is a tributary of the Missouri River, which itself is a tributary of the Mississippi River which flows to the Gulf of Mexico. The Platte over most of its length is a broad, shallow, meandering stream with a sandy bottom and many islands—a braided stream.
The headwaters of a river or stream is the farthest place in that river or stream from its estuary or downstream confluence with another river, as measured along the course of the river. It is also known as a river's source.
The Nodaway River is a 65.7-mile-long (105.7 km) river in southwest Iowa and northwest Missouri.
Big Black River is a river in the U.S. state of Mississippi and a tributary of the Mississippi River. Its origin is in Webster County near the town of Eupora in the north central part of the state. From there it flows 330 miles (530 km) in a generally southwest direction until it merges with the Mississippi River 25 miles (40 km) south of the city of Vicksburg. It is the major contributor to the Big Black River Basin. It forms part of the northern border of Choctaw County, passes through Montgomery County, and forms the eastern border of Holmes County and the northern border of Claiborne County.
A hydrological code or hydrologic unit code is a sequence of numbers or letters that identify a hydrological unit or feature, such as a river, river reach, lake, or area like a drainage basin or catchment.
The Upper Mississippi water resource region is one of 21 major geographic areas, or regions, in the first level of classification used by the United States Geological Survey to divide and sub-divide the United States into successively smaller hydrologic units. These geographic areas contain either the drainage area of a major river, or the combined drainage areas of a series of rivers.
