List of longest rivers of the United States (by main stem) explained

The longest rivers of the United States include 38 that have main stems of at least 500miles long. The main stem is "the primary downstream segment of a river, as contrasted to its tributaries". The United States Geological Survey (USGS) defines a main-stem segment by listing coordinates for its two end points, called the source and the mouth. Some well-known rivers like the Atchafalaya, Willamette, and Susquehanna are not included in this list because their main stems are shorter than 500 miles.

Seven rivers in this list cross or form international boundaries. Three—the Milk River, the Red River of the North, and the Saint Lawrence River—begin in the United States and flow into Canada; two do the opposite (Yukon and Columbia). Also a segment of the Saint Lawrence River forms the international border between part of the province of Ontario, Canada, and the U.S. state of New York. Of these seven rivers, only the Milk River crosses the international border twice, leaving and then re-entering the United States. Two rivers, the Colorado and the Rio Grande, begin in the United States and flow into or form a border with Mexico. In addition, the drainage basins of the Mississippi and Missouri rivers extend into Canada,^{[1] [2]} and the basin of the Gila River extends into Mexico.^[3]

Sources report hydrological quantities with varied precision. Biologist and author Ruth Patrick, describing a table of high-discharge U.S. rivers, wrote that data on discharge, drainage area, and length varied widely among authors whose works she consulted. "It seems," she said, "that the wisest course is to regard data tables such as the present one as showing the general ranks of rivers, and not to place too much importance on minor (10–20%) differences in figures."

Table

The primary source for watershed and discharge data in the table below is Rivers of North America. Conflicting data from other sources, if the difference is greater than 10 percent, is reported in the notes. Discharge refers to the flow at the mouth. In the "States, provinces, and image" column, the superscripts "s" and "m" indicate "source" and "mouth". Non-U.S. states appear in italics. Except in the "States, provinces, and image" column, abbreviations are as follows: "km" for "kilometer", "mi" for "mile", "s" for "second", "m" for "meter", and "ft" for "foot".

Key
River is not entirely within the United States.
Watershed is not entirely within the United States.

! scope="col" width=10%

Name	Length	States, provinces, and map^[4]	Source coordinates^[5]	Mouth	Mouth coordinates	Watershed area^[6]	Discharge	Photo
1	Missouri River	mi 3,768 km	Montana^s, North Dakota, South Dakota, Nebraska, Iowa, Kansas, Missouri^m	45.9275°N -111.5081°W^[7]	Mississippi River	38.8136°N -90.1197°W	mi^2 1,371,017 km^2	ft^3/s 1,956 m^3/s
2	Mississippi River	mi 3,766 km	Minnesota^s, Wisconsin, Iowa, Illinois, Missouri, Kentucky, Tennessee, Arkansas, Mississippi, Louisiana^m	47.2394°N -95.2081°W^[8]	Gulf of Mexico	29.1511°N -89.2533°W	mi^2 3,270,000 km^2	ft^3/s 18,400 m^3/s
3	Yukon River	mi 3,190 km	British Columbia^s, Yukon Territory, Alaska^m	59.5833°N -133.7833°W^[9]	Bering Sea	62.5986°N -164.8°W^[10]	mi^2 839,200 km^2	ft^3/s 6,340 m^3/s
4	Rio Grande	mi 2,830 km	Colorado^s, New Mexico, Texas^m, Chihuahua, Coahuila, Nuevo León, Tamaulipas^m	37.7978°N -107.5383°W^[11]	Gulf of Mexico	25.9561°N -97.1453°W	mi^2 870,000 km^2	ft^3/s 37 m^3/s
5	Colorado River	mi 2,330 km	Colorado^s, Utah, Arizona, Nevada, California, Sonora^m, Baja California^m	40.4722°N -105.8261°W^[12]	Gulf of California	31.8158°N -114.8061°W^[13]	mi^2 642,000 km^2	ft^3/s 40 m^3/s
6	Arkansas River	mi 2,322 km	Colorado^s, Kansas, Oklahoma, Arkansas^m	39.2583°N -106.3439°W^[14]	Mississippi River	33.775°N -91.0708°W	mi^2 414,910 km^2	ft^3/s 1,004 m^3/s
7	Columbia River	mi 2,000 km	British Columbia^s, Washington^m, Oregon^m	50.2167°N -115.85°W^[15]	Pacific Ocean	46.2442°N -124.0581°W^[16]	mi^2 724,024 km^2	ft^3/s 7,730 m^3/s
8	Red River	mi 1,811 km	Oklahoma^s, Texas, Arkansas, Louisiana^m	34.5764°N -99.965°W^[17]	Atchafalaya and Mississippi rivers	31.0194°N -91.7478°W	mi^2 169,890 km^2	ft^3/s 852 m^3/s
9	Snake River	mi 1,674 km	Wyoming^s, Idaho, Oregon, Washington^m	44.1303°N -110.2194°W^[18]	Columbia River	46.1861°N -119.0286°W	mi^2 281,000 km^2	ft^3/s 1,565 m^3/s
10	Ohio River	mi 1,575 km	Pennsylvania^s, Ohio, West Virginia, Indiana, Illinois, Kentucky^m	40.4428°N -80.0172°W^[19]	Mississippi River	36.9867°N -89.1306°W	mi^2 529,000 km^2	ft^3/s 8,733 m^3/s
11	Colorado River of Texas	mi 1,560 km	Texas^s, m	32.6797°N -101.7308°W^[20]	Gulf of Mexico	28.5947°N -95.9831°W	mi^2 103,341 km^2	ft^3/s 75 m^3/s
12	Tennessee River	mi 1,504 km	Tennessee^s, Alabama, Mississippi, Kentucky^m	35.9592°N -83.8503°W^[21]	Ohio River	37.0672°N -88.5647°W	mi^2 105,870 km^2	ft^3/s 2,000 m^3/s
13	Canadian River	mi 1,458 km	Colorado^s, New Mexico, Texas, Oklahoma^m	37.0197°N -105.0758°W^[22]	Arkansas River	35.4533°N -95.0328°W	mi^2 122,070 km^2	ft^3/s 174 m^3/s
14	Brazos River	mi 1,390 km	Texas^s, m	33.2686°N -100.0103°W^[23]	Gulf of Mexico	28.8758°N -95.3783°W	mi^2 115,566 km^2	ft^3/s 249 m^3/s
15	Green River	mi 1,230 km	Wyoming^s, Colorado, Utah^m	43.1536°N -109.6717°W^[24]	Colorado River	38.1892°N -109.8853°W	mi^2 116,200 km^2	ft^3/s 172 m^3/s
16	Pecos River	mi 1,175 km	New Mexico^s, Texas^m	35.9761°N -105.5581°W^[25]	Rio Grande	29.6997°N -101.3714°W	mi^2 113,960 km^2	ft^3/s 2 m^3/s
17	White River (Arkansas)	mi 1,159 km	Arkansas^s, m, Missouri	35.8389°N -93.6044°W^[26]	Mississippi River	33.9514°N -91.0814°W	mi^2 72,189 km^2	ft^3/s 979 m^3/s
18	James River	mi 1,140 km^[27]	North Dakota^s, South Dakota^m	47.4814°N -99.8589°W^[28]	Missouri River	42.8714°N -97.2906°W	mi^2 54,240 km^2^[29]	ft^3/s 24.2 m^3/s
19	Kuskokwim River	mi 1,130 km	Alaska^s, m	63.0878°N -154.6425°W^[30]	Bering Sea	60.0831°N -162.3339°W	mi^2 124,319 km^2	ft^3s 1,900 m^3/s
20	Cimarron River	mi 1,123 km^[31]		36.9067°N -102.9867°W^[32]	Arkansas River	36.1706°N -96.2719°W	mi^2 50,540 km^2	ft^3/s 42 m^3/s
21	Cumberland River	mi 1,120 km		36.845°N -83.3239°W^[33]	Ohio River	37.1433°N -88.4075°W	mi^2 46,430 km^2	ft^3/s862 m^3/s
22	Yellowstone River	mi 1,091 km	Wyoming^s, Montana, North Dakota^m	43.9883°N -109.9292°W^[34]	Missouri River	47.9783°N -103.9822°W	mi^2 182,336 km^2	ft^3/s 362 m^3/s
23	North Platte River	mi 1,070 km	Colorado^s, Wyoming, Nebraska^m	40.6397°N -106.4053°W^[35]	Platte River	41.1139°N -100.6758°W	mi^2 90,352 km^2	ft^3/s 21.9 m^3/s
24	Milk River	mi 1,005 km	Alberta, Montana^s, m	48.8556°N -113.0194°W^[36]	Missouri River	48.0572°N -106.3186°W	mi^2 57,839 km^2	ft^3/s 18.9 m^3/s
25	Ouachita River	mi 974 km^[37]	Arkansas^s, Louisiana^m	31.6989°N -94.3325°W^[38]	Black River	31.6314°N -91.8069°W	mi^2 64,454 km^2	ft^3/s 843 m^3/s
26	St. Lawrence River	mi 965 km	New York^s, Ontario^s, Quebec^m	44.0986°N -76.3911°W^[39]	Gulf of St. Lawrence	49.6667°N -64.5°W^[40]	mi^2 1,600,000 km^2	ft^3/s 12,600 m^3/s
27	Gila River	mi 960 km	New Mexico^s, Arizona^m	33.1797°N -108.2061°W^[41]	Colorado River	32.7197°N -114.5553°W	mi^2 149,832 km^2	ft^3/s 6 m^3/s
28	Sheyenne River	mi 951 km^[42]	North Dakota^s, m	47.6961°N -100.4978°W^[43]	Red River of the North	47.0236°N -96.8253°W	mi^2 23,000 km^2	ft^3/s 8.2 m^3/s
29	Tanana River	mi 940 km	Alaska^s, m	63.0492°N -141.8644°W^[44]	Yukon River	65.1606°N -151.9603°W	mi^2 114,000 km^2	ft^3/s 1,185 m^3/s
30	Smoky Hill River	mi 927 km	Colorado^s, Kansas^m	38.9503°N -102.5803°W^[45]	Kansas River	39.06°N -96.8011°W	mi^2 49,900 km^2	ft^3/s 43.7 m^3/s
31	Niobrara River	mi 914 km	Wyoming^s, Nebraska^m	42.8208°N -104.6472°W^[46]	Missouri River	42.7661°N -98.0472°W	mi^2 32,600 km^2	ft^3/s 49 m^3/s
32	Little Missouri River	mi 900 km^[47]	Wyoming^s, Montana, South Dakota, North Dakota^m	44.5403°N -104.9992°W^[48]	Missouri River	47.6106°N -102.8733°W	mi^2 21,500 km^2^[49]	ft^3/s 13 m^3/s
33	Sabine River	mi 890 km	Texas^s, Louisiana^m	32.8081°N -95.9206°W^[50]	Gulf of Mexico	29.9856°N -93.7906°W	mi^2 25,268 km^2	ft^3/s 238 m^3/s
34	Red River of the North	mi 890 km^[51]	North Dakota^s, Minnesota^s, Manitoba^m	46.2644°N -96.5986°W^[52]	Lake Winnipeg	50.3964°N -96.8108°W^[53]	mi^2 287,500 km^2	ft^3/s 236 m^3/s
35	Des Moines River	mi 845 km^[54]	Minnesota^s, Missouri, Iowa^m	44.0839°N -95.6881°W^[55]	Mississippi River	41.3811°N -91.4225°W	mi^2 31,127 km^2	ft^3/s 182 m^3/s
36	White River (Missouri River)	mi 815 km	Nebraska^s, South Dakota^m	42.6861°N -103.8372°W^[56]	Missouri River	43.7139°N -99.4669°W	mi^2 26,418 km^2	ft^3/s 16 m^3/s
37	Trinity River	mi 815 km	Texas^s, m	32.7983°N -96.8978°W^[57]	Galveston Bay	29.7431°N -94.7033°W	mi^2 46,540 km^2	ft^3/s 222 m^3/s
38	Wabash River	mi 810 km	Ohio^s, Indiana^m, Illinois^m	40.3519°N -84.7658°W^[58]	Ohio River	37.7981°N -88.0272°W	mi^2 85,340 km^2	ft^3/s 28 m^3/s

See also

• List of longest rivers in the United States by state
  • List of longest streams of Idaho
  • List of longest streams of Minnesota
  • List of longest streams of Oregon
• List of rivers by length

Works cited

• Book: Benke. Arthur C.. Cushing. Colbert E.. Rivers of North America. Burlington, Massachusetts. Elsevier Academic Press. 2005. 978-0-12-088253-3. registration.
• Book: Patrick, Ruth. Rivers of the United States: Volume II: Chemical and Physical Characteristics. 1995. John Wiley & Sons. New York. 24. 978-0-471-10752-1.

Notes and References

1. Web site: Rivers . The Atlas of Canada . Natural Resources Canada . February 11, 2011 . dead . https://web.archive.org/web/20070404150649/http://atlas.nrcan.gc.ca/site/english/learningresources/facts/rivers.html . April 4, 2007 .
2. Web site: Missouri River Basin Basic Geography and Natural Features. United States Geological Survey. February 20, 2011. https://web.archive.org/web/20140407083039/http://aa179.cr.usgs.gov/basin/dynamap.html. April 7, 2014. dead.
3. Web site: McCord. Marc W.. Gila River. Wind Spirit Community. February 20, 2011. https://web.archive.org/web/20170303184344/http://www.windspiritcommunity.org/gila_river.htm. March 3, 2017. live.
4. Book: The Road Atlas. registration. Rand McNally & Company. 2008. Chicago, Illinois. 978-0-528-93961-7.
5. The mouth coordinates and source coordinates are from the Geographic Names Information System (United States Geological Survey) or the Canadian Geographical Names Data Base except for the coordinates of the mouth of the Colorado River, derived by geolocating with Google Earth.
6. From Rivers of North America (ed. Benke and Cushing) unless otherwise noted.
7. Web site: [{{gnis3|756398}} Missouri River]. Geographic Names Information System (GNIS) . United States Geological Survey . October 24, 1980. February 4, 2011.
8. Web site: [{{gnis3|1629903}} Mississippi River]. Geographic Names Information System (GNIS) . United States Geological Survey . June 4, 1980. February 4, 2011.
9. Web site: Atlin Lake (B.C.) . Natural Resources Canada . February 4, 2011 . https://web.archive.org/web/20110706184115/http://geonames2.nrcan.gc.ca/cgi-bin/v9/sima_unique_v9?english%3FJCTAR%3FC . July 6, 2011 . dead .
10. Web site: [{{gnis3|1416412}} Yukon River]. Geographic Names Information System (GNIS) . United States Geological Survey . March 31, 1981. February 4, 2011.
11. Web site: [{{gnis3|1385432}} Rio Grande]. Geographic Names Information System (GNIS) . United States Geological Survey . March 30, 1979. February 4, 2011.
12. Web site: [{{gnis3|45730}} Colorado River]. Geographic Names Information System (GNIS) . United States Geological Survey . February 8, 1980. February 4, 2011.
13. Derived via Google Earth
14. Web site: [{{gnis3|78956}} Arkansas River]. Geographic Names Information System (GNIS) . United States Geological Survey . November 30, 1979. February 4, 2011.
15. Web site: Columbia Lake . Natural Resources Canada . January 31, 2011 . dead . https://web.archive.org/web/20110706184119/http://geonames2.nrcan.gc.ca/cgi-bin/v9/sima_unique_v9?english%3FJATIP%3FC . July 6, 2011 .
16. Web site: [{{Gnis3|1140014}} Columbia River ]. Geographic Names Information System . United States Geological Survey . November 28, 1980 . August 5, 2010.
17. Web site: [{{gnis3|558728}} Red River]. Geographic Names Information System (GNIS) . United States Geological Survey . June 4, 1980. February 5, 2011.
18. Web site: [{{gnis3|1533479}} Snake River]. Geographic Names Information System (GNIS) . United States Geological Survey . September 10, 1979. August 6, 2010.
19. Web site: [{{gnis3|425264}} Ohio River]. Geographic Names Information System (GNIS) . United States Geological Survey . October 24, 1980. February 5, 2011.
20. Web site: [{{gnis3|1384149}} Colorado River]. Geographic Names Information System (GNIS) . United States Geological Survey . November 30, 1979. February 5, 2011.
21. Web site: [{{gnis3|517033}} Tennessee River]. Geographic Names Information System (GNIS) . United States Geological Survey . September 20, 1979. February 5, 2011.
22. Web site: [{{gnis3|1101881}} Canadian River]. Geographic Names Information System (GNIS) . United States Geological Survey . December 18, 1979. February 5, 2011.
23. Web site: [{{gnis3|1384148}} Brazos River]. Geographic Names Information System (GNIS) . United States Geological Survey . November 30, 1979. February 5, 2011.
24. Web site: [{{gnis3|1428399}} Green River]. Geographic Names Information System. United States Geological Survey (USGS). December 31, 1979. February 5, 2011.
25. Web site: [{{gnis3|1384150}} Pecos River]. Geographic Names Information System. United States Geological Survey (USGS). November 30, 1979. February 5, 2011.
26. Web site: [{{gnis3|78762}} White River]. Geographic Names Information System. United States Geological Survey (USGS). April 30, 1980. February 5, 2011.
27. Web site: River Facts. American Rivers. February 22, 2011. https://web.archive.org/web/20120310033450/http://www.americanrivers.org/library/river-facts/river-facts.html. March 10, 2012. dead.
28. Web site: [{{gnis3|1261082}} James River]. Geographic Names Information System. United States Geological Survey (USGS). February 13, 1980. February 22, 2011.
29. Web site: USGS 06478513 James River near Yankton, SD. United States Geological Survey. November 2010. February 23, 2011.
30. Web site: [{{gnis3|1416402}} Kuskokwim River]. Geographic Names Information System. United States Geological Survey (USGS). January 1, 2000. February 5, 2011.
31. Web site: Cimarron River. Oklahoma Historical Society. February 5, 2011. https://web.archive.org/web/20141227051709/http://digital.library.okstate.edu/encyclopedia/entries/C/CI004.html. December 27, 2014. dead.
32. Web site: [{{gnis3|1091369}} Cimarron River]. Geographic Names Information System. United States Geological Survey (USGS). December 18, 1979. February 5, 2011.
33. Web site: [{{gnis3|517018}} Cumberland River]. Geographic Names Information System. United States Geological Survey (USGS). September 20, 1979. February 5, 2011.
34. Web site: [{{gnis3|1035255}} Yellowstone River]. Geographic Names Information System. United States Geological Survey (USGS). February 13, 1980. January 20, 2011.
35. Web site: [{{gnis3|204647}} North Platte River]. Geographic Names Information System. United States Geological Survey (USGS). October 13, 1978. February 6, 2011.
36. Web site: [{{gnis3|774213}} Milk River]. Geographic Names Information System. United States Geological Survey (USGS). April 4, 1980. February 5, 2011.
37. Benke and Cushing, p. 265
38. Web site: [{{gnis3|558280}} Ouachita River]. Geographic Names Information System. United States Geological Survey (USGS). January 1, 2000. February 6, 2011.
39. Web site: [{{gnis3|977244}} St. Lawrence River]. Geographic Names Information System. United States Geological Survey (USGS). January 1, 2000. February 3, 2011.
40. Web site: Saint Lawrence River. Natural Resources Canada. February 3, 2011. https://web.archive.org/web/20110706184123/http://geonames2.nrcan.gc.ca/cgi-bin/v9/sima_unique_v9?english%3FEFGFK%3FC. July 6, 2011. dead.
41. Web site: [{{gnis3|42838}} Gila River]. Geographic Names Information System. United States Geological Survey (USGS). February 8, 1980. February 6, 2011.
42. Web site: National Hydrography Dataset. United States Geological Survey. June 9, 2011.
43. Web site: [{{gnis3|1035146}} Sheyenne River]. Geographic Names Information System. United States Geological Survey (USGS). February 13, 1980. June 9, 2011.
44. Web site: [{{gnis3|1416408}} Tanana River]. Geographic Names Information System. United States Geological Survey (USGS). January 1, 2000. February 2, 2011.
45. Web site: [{{gnis3|485314}} Smoky Hill River]. Geographic Names Information System. United States Geological Survey (USGS). October 13, 1978. June 14, 2011.
46. Web site: [{{gnis3|835960}} Niobrara River]. Geographic Names Information System. United States Geological Survey (USGS). March 9, 1979. July 5, 2011.
47. Personius. Robert Giles. Eddy, Samuel . Fishes of the Little Missouri River. Copeia. American Society of Ichthyologists and Herpetologists. 1955. February 18, 1955. 1. 41. 10.2307/1439450. 1439450 .
48. Web site: [{{gnis3|1034981}} Little Missouri River]. Geographic Names Information System. United States Geological Survey (USGS). February 13, 1980. February 23, 2011.
49. Web site: USGS 06337000 Little Missouri River near Watford City, ND. November 2010. February 23, 2011.
50. Web site: [{{gnis3|555872}} Sabine River]. Geographic Names Information System. United States Geological Survey (USGS). June 4, 1980. February 7, 2011.
51. Web site: Red River of the North. Minnesota Department of Natural Resources. 2011. January 22, 2011.
52. Web site: [{{gnis3|1035890}} Red River of the North]. Geographic Names Information System. United States Geological Survey (USGS). January 1, 2000. January 17, 2011.
53. Web site: Red River. Natural Resources Canada. January 17, 2011. https://web.archive.org/web/20110706184128/http://geonames2.nrcan.gc.ca/cgi-bin/v9/sima_unique_v9?english%3FGAWTC%3FC. July 6, 2011. dead.
54. Web site: National Recreation Trails: Des Moines River Water Trail - Polk County, Iowa. American Trails. February 5, 2011.
55. Web site: [{{gnis3|465582}} Des Moines River]. Geographic Names Information System. United States Geological Survey (USGS). April 30, 1979. February 7, 2011.
56. Web site: [{{gnis3|1267248}} White River]. Geographic Names Information System. United States Geological Survey (USGS). February 13, 1980. February 7, 2011.
57. Web site: [{{gnis3|1348789}} Trinity River]. Geographic Names Information System. United States Geological Survey (USGS). November 30, 1979. February 7, 2011.
58. Web site: [{{gnis3|449850}} Wabash River]. Geographic Names Information System. United States Geological Survey (USGS). February 14, 1979. July 5, 2011.