50 Largest Rivers in the United States (by discharge)

The United States of America is home to hundreds of rivers, and with a land area of 9.834 million km², the country can house several huge rivers. Approximately half of the rivers on the list are tributaries to other rivers on the list; the remaining rivers flow straight into oceans, seas, gulfs, or bays.

1. Mississippi River

Mississippi is the largest river in the United States with an average discharge volume of 593,000 CFS (cubic feet per second) at the mouth. The calculation of the discharge excluding the Atchafalaya-Red River basin.

Discharge (cfs): 593,000
Drainage area: 1,150,000 sq miles in the U.S and Canada
Source: Lake Itasca
Source Location: Itasca State Park, Clearwater County, Minnesota. 47°14′23″N 95°12′27″W

2. Ohio River

The Ohio River, located in the southern United States, is the second-largest river by discharge. Its drainage basin encompasses a portion of 14 states. The river’s depth ranged from around 3 to 20 feet. It has dams and a network of reservoirs.

Discharge (cfs): 281,500
Drainage area: 203,000 sq miles
Source: Allegheny River
Source Location: Allegany Township, Potter County, Pennsylvania. 47°14′23″N 95°12′27″W

3. Saint Lawrence River

It is the second-largest river in the United States, with a discharge rate of 275,000 CFS of water emptying at the US-Canada border, making it the second-largest river in the country. The St. Lawrence River flows beside Gananoque, Brockville, Morristown, Ogdensburg, Massena, Cornwall, Montreal, Trois-Rivières, and Quebec City before draining into the Gulf of St. Lawrence.

Discharge (cfs): 275,000
Drainage area: 258,000 sq miles
Source: Lake Ontario
Source Location: Kingston, Ontario / Cape Vincent, New York. 44°06′N 76°24′W

4. Columbia River

Columbia is one of the largest and longest rivers in the USA. The river originates in British Columbia’s Rocky Mountains. It runs northwest and then south into Washington, then heads west to form the majority of the border between Washington and Oregon before draining into the Pacific Ocean. its largest tributary is the Snake River. Its drainage basin stretches over seven US states and one Canadian province.

Discharge (cfs): 273,000
Drainage area: 258,000 sq miles
Source: Columbia Lake
Source Location: British Columbia, Canada. 50°13′35″N 115°51′05″W

5. Yukon River

It runs across the Canadian territory of Yukon., (Yukon is Canada’s territory named after the river). Yukon River is the longest in Alaska and Yukon territory. The 75%half of the river flows westward through the state of Alaska in the United States.

Discharge (cfs): 227,000
Drainage area: 328,000 sq miles
Source: Llewellyn Glacier
Source Location: Atlin District, British Columbia, Canada. 59°10′N 133°50′W

No	River	Length (km)	Average discharge (cfs) (ft3/s)	Mouth
1	Mississippi River	3,730	593,000	Gulf of Mexico (Pilottown, Plaquemines Parish, LA)
2	Ohio River	1,575	281,500	Mississippi River (Cairo, Illinois / Ballard County, Kentucky)
3	Saint Lawrence River	965	275,000 (In U.S. side)	Gulf of Saint Lawrence (Quebec, Canada)
4	Columbia River	2,000	273,000	Pacific Ocean (Pacific Ocean, at Clatsop County, Oregon)
5	Yukon River	3,185	227,000	Bering Sea (Kusilvak, Alaska, U.S.)
6	Atchafalaya River	220	225,000	Gulf of Mexico (Morgan City, Louisiana)
7	Niagara River	58	204,700	Lake Ontario
8	Detroit River	51	188,000	Lake Erie
9	St. Clair River	63	183,000	Lake St. Clair
10	Missouri River	3,767	86,300	Mississippi River
11	St. Marys River	120	75,000	Lake Huron-Lake Michigan
12	Tennessee River	1,049	68,000	Ohio River
13	Mobile River	72	67,000	Gulf of Mexico
14	Kuskokwim River	1,130	67,000	Bering Sea
15	Red River	2,190	58,000	Atchafalaya River
16	Copper River	470	57,400	Gulf of Alaska
17	Snake River	1,674	55,000	Columbia River
18	Stikine River	610	56,000	Pacific Ocean
19	Susitna River	504	51,000	Gulf of Alaska
20	Arkansas River	2,322	44,500	Mississippi River
21	Tanana River	940	41,800	Yukon River
22	Susquehanna River	747	38,200	Chesapeake Bay
23	Willamette River	301	37,400	Columbia River
24	Wabash River	810	34,500	Ohio River
25	Alabama River	512	32,500	Mobile River
26	Nushagak River	450	32,000	Bering Sea
27	Alsek River	386	31,000	Gulf of Alaska
28	Cumberland River	1,120	30,000	Ohio River
29	Black River-Ouachita River	974	29,800	Red River
30	White River	1,159	29,500	Mississippi River
31	Pend Oreille River	210	27,000	Columbia River
32	Tombigbee River	320	26,300	Mobile River
33	Koyukuk River	684	25,000	Yukon River
34	Illinois River	439	24,000	Mississippi River
35	Sacramento River	719	23,500	Pacific Ocean
36	Porcupine River	916	23,000	Yukon River
37	Colorado River	2,330	22,000	Gulf of California
38	Clark Fork River	500	21,900	Pend Oreille River
39	Hudson River	507	21,900	Atlantic Ocean
40	Yentna River	121	21,000	Susitna River
41	Chitina River	180	20,000	Copper River
42	Allegheny River	523	19,900	Ohio River
43	Apalachicola River	80	19,602	Gulf of Mexico
44	Connecticut River	655	18,400	Atlantic Ocean
45	Kvichak River	80	17,900	Bering Sea
46	Klamath River	423	17,300	Pacific Ocean
47	Santee River	230	17,000	Atlantic Ocean
48	Skagit River	240	16,500	Pacific Ocean
49	Kootenai (Kootenay) River	781	27,600	Columbia River
50	Coosa River	450	16,000	Alabama River