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 primary river and second-longest river of the largest drainage basin in the United States. From its traditional source of Lake Itasca in northern Minnesota, it flows generally south for 2,340 miles (3,766 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 a river in the Central and Mountain West regions of the United States. The nation's longest, it rises in the eastern Centennial Mountains of the Bitterroot Range of the Rocky Mountains of southwestern Montana, then flows east and south for 2,341 miles (3,767 km) before entering the Mississippi River north of St. Louis, Missouri. The river drains 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 slightly 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 meandering river in northeastern Kansas in the United States. It is potentially the southwestern most part of the Missouri River drainage, which is sometimes 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 American 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 headwater of a river or stream is the farthest point on each of its tributaries upstream from its mouth/estuary into a lake/sea or its confluence with another river. Each headwater is considered one of the river's sources, as it is the place where surface runoffs from rainwater, meltwater and/or spring water begin accumulating into a more substantial and consistent flow that becomes a first-order tributary of that river. The tributary with the longest course downstream of the headwaters is regarded as the main stem.
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.
The Thompson River is the largest tributary of the Grand River in the central United States, flowing from southern Iowa into Missouri. In Iowa, it is known simply as the Grand River and passes near the city of Grand River. The river is 188 miles (303 km) long, and its drainage basin is roughly 1,850 square miles (4,800 km2), of which 1,111 square miles (2,880 km2) are in Missouri.
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.
