GEOLOGICAL SURVEY CIRCULAR 44

May 1949

LARGE RIVERS OF THE UNITED STATES

Prepared by Water Resources Division
UNITED STATES DEPARTMENT OF THE INTERIOR 

J. A. Krug, Secretary

GEOLOGICAL SURVEY 

W. E. Wrather, Director

WASHINGTON, D. C.

Free on application to the Director, Greological Survey, Washington 25, D. C.
Circular 44

CORRECTION

* 

Figure 1

Cableway across Columbia River near The Dalles fi Oreg<, has a clear span 

of 172? fee*, steel towers are 100 feet high* Instailatio* by UcS* Geolegloal 

Survey,, completed In 19St

LARGE RIVERS OF THE UNITED STATES

Prepared by Water Resources Division

Everyone knows that the Mississippi River 

Is the largest river in the United States. 

But what rivers are the second and third largest? To compare the size of rivers, one must 

know what Is meant by large or small.

The simplest measurement to use, and the 

most common In our school geographies, Is 

length. Length Is most meaningful in comparing navigable rivers. The thousands of miles 

of navigation afforded by the Mississippi - 

Ohio-Missouri River system played a large and 

significant part In the development of the 

interior of our country. The great navigable 

length of the Missouri made it an Important 

arterial trail to the West. It Is Interesting 

to consider the profound extent to which the 

settlement of the West might have been altered 

had the early Spanish settlers In Mexico been

able to ascend the Colorado by boat.

Rivers may also be compared In relation 

to the size of the basin drained. Drainage 

area Is "a measure of the region contributory 

to a river, but Is not so much a characteristic of the river itself.

It Is the flow of water in the river that 

turns the wheels of industry, supplies water 

for cities and for innumerable Industrial processes , and maintains navigable depths for 

shipping. Consequently, the flow of a river 

Is perhaps the most significant Index of Its 

utility In a highly productive country. It 

tells us how much water the river can supply 

for development. Therefore, In this report, 

rivers are classified with respect to their 

flows. Their lengths and their drainage areas

Figure 1. Cableway across Columbia River near The Dalles, Oreg., for measuring river discharge.

The cableway supports a car from which an engineer operates a current meter to measure the speed of the water, and a 

sounding weight to measure the depth of the water.! Supporting the 1,237 foot cableway are two 54-foot towers, 

one on each side of the river. The maximum flow that| has been measured was about 1,000,000 cfs during the floods, 

of May-June 1948.

1
are listed for subsidiary classification.

Possibly the first effort to classify 

rivers on the basis of flow was made in 1880 

by H. B. Guppy, a British naturalist. Dr. 

Guppy, who had made some measurements of the 

Yangtse and Pel-Ho Rivers In China, using 

floats and sounding lines, was curious to 

know how his measurements compared with measurements on other rivers of the world. He 

was able to collect Information as to the relative magnitude of the flow of 17 rivers. In 

1880 facts on river flow were obtained only 

by specially Investigative-minded Individuals 

like Dr. Guppy and published data 'were very 

limited, -- and still are In many parts of 

the world. About this time the United States 

Geological Survey began Its river measurement 

work in the West to obtain needed stream-flow 

information -so that settlers and other water 

users might know how much water was available 

for irrigation and other purposes. Water 

users In other parts of the country also needed 

stream-flow Information. There are now about 

6,000 gaging stations In continuous operation 

on rivers, large and small, to guide the control and utilization of the nation's water 

resources. The Geological Survey maintains 

gaging stations near the mouths of most of 

the large rivers of the United States. A 

photograph of the measuring cableway on the 

Columbia River near The Dalles, Oreg. Is shown 

on figure 1. A list of the gaging stations 

maintained by the Geological Survey near the 

mouths of the large rivers of the United States 

is given in table Is The list includes the 

drainage area above each gaging station and

the mean flow in cubic feet per second.

For practical reasons it Is not often 

feasible to operate gaging stations directly 

at the mouth of a river. Therefore, in order 

to determine the flow at the mouth, It becomes 

necessary to add the Inflow to the river below 

the most downstream gaging station. For most 

rivers this additional flow is minor in comparison with that measured at the gaging s-tatlon. -Flows in cubic feet per second thus 

computed are listed In table 2 for the 26 largest streams In the country in order of volume 

of flow. No figures of flow are shown for 

the White, Sacramento and Colorado Rivers because the unmeasured flow was so great in proportion to the total, or so uncertain that no 

dependable estimate could be made for flow at 

the mouth. However, these rivers are listed 

in what is believed to be their proper rank 

in relation to others in the table. The Information on discharge In tables 1 and 2 has 

been computed from basic data especially for 

this report. Data on lengths and drainage 

areas In table 2, on the other hand, have been 

obtained from previously published sources. 

The locations of the rivers listed are shown 

on figure 2. The rivers are drawn so as to 

show their relative rates of flow.

The Mississippi, early named "Father of 

Waters", is the greatest river by all standards 

of comparison, -- flow, drainage area, and 

length. Of Its tributaries or components, 11 

are Included among the ranking 26 rivers in 

the United States. The Mississippi together 

with a parallel distributary, the Atchafalaya,

Table 1.-Discharge at downstream gaging stations on large rivers

River

Alabama

Allegheny

Apalachlcola

Arkansas

Colorado

Columbia

Cumberland

Delaware

Hudson

Illinois

Mississippi

Mississippi

Missouri

Ohio

Pend Orel lie

Red

Sacramento

St. Lawrence

Snake

Susquehanna

Tennessee

Tomblgbee

Wabash

White

Willamette -

Gaging station 

location

At Claiborne, Ala.

At Natrona, Pa.

At Chattahoochee , Fla.

At Little Rock, Ark.

At Yuma, Arlz. a/

Near The Dalles, Oreg.

At Smithland, Ky.

At Trenton, N. J. b/

Below Mohawk River, N. Y. c/

At Meredosia, 111.

At Alton, 111.

At Vicksburg, Miss. '

At Hermann, Mo.

At Metropolis, 111.

Below Z Canyon', Wash.

At Alexandria, La. d/

At Verona, Calif, e/

At -Ogdensburg, N. Y. f/

Near Clarkston, Wash.

At Marietta, Pa.

Near Johnsonville, Tenn.

Near Leroy, Ala.

At New Harmony, Ind.

At Newport, Ark.

At Salem, Oreg.

Drainage 

area 

( s quare ml le s )

22,000

11,410

17,100

157 , 900

242,900

237,000

18,080

9,167

7,956

25,300

171,500

1,144,500

528,200

203,000

25,200

81,300

-

298,100

103,200

25,990

38,520

19,100

29,160

19,800

7,280

Mean 

discharge 

(1921-45) 

(cfs)

30,800

18,700

21,400

44,500

14,800

168,000

27,800

14,900

12 , 800

24,800

91,200

561,000

70,000

254,000

24,000

51 , 000

21,400

221,000

44,500

33 , 800

60,400

26,400

27,500

24,500

21,150

a Wasteway flow has been added. A considerable part of the natural flow is used for irrigation in the basin above Yuma.

b Five tributaries below Trenton have been added.

c Sum of flow at gaging stations on Hudson River at Mechanicvllie, N. Y. and Mohawk River at Cohoes, N. Y.

d Ouachlta River at Monroe, La., has been added.

e American River and Yolo bypass have been added.

f Operated by Corps of Engineers, Department of the Army.
U.S. GEOLOGICAL SURVEY

EXPLANATION

20,000 Cfs

50,000 ii

100,000 ii

250,000 ii

500,000 ii

Rivers shown are those whose average flow at the 

mouth is 19,000 cubic feet per second or more.

Figure 2. Large rivers in the United States.
discharges the water that drains from 40 percent of the land area of continental United 

States. Table 2 shows that the Ohio, Columbia, 

and St. Lawrence Rivers are respectively second, third, and fourth ranking rivers In respect to flow. There is a large difference 

in the discharges of the fourth and fifth 

ranking rivers given in table 2. The uppir 

Mississippi River has only about 40 percent 

of the flow of the St. Lawrence River, which 

occupies the fourth position in the list. The 

differences in flow of the remaining streams' 

become progressively smaller.

Rivers vary in flow from year to year. In 

order to standardize results and to minimize 

the effects of these variations on the comparisons, the flows of all rivers h%ve been based 

on the average over the 25-year period, 1921-45. 

The order of magnitude of the rivers listed in 

table 2 may depend In part on the period of 

record on which the flows are based. For example, the trend In flow of the Columbia River 

has been generally downward since about 1895. 

A similar trend has been true of other rivers, 

though perhaps to a lesser degree. Therefore, 

if comparisons were based on 50-year records 

(if available for both streams), the Columbia 

River might outrank the Ohio River. Other reversals, where order of rank Is based on small 

differences In flow, might also occur if the 

flows were based on a period other than 1921-45.

The flows of most western rivers, such as 

the Columbia, Snake, Missouri, and Colorado, 

are depleted by diversions for irrigation. 

These depletions have not been considered In 

preparing table 2, except on the Colorado River, 

where no entry for the flow Is given, but the 

relative position was based on estimates of 

the virgin flow (I.e., by adding the depletions 

for irrigation to the measured flow). In 

general these depletions would not greatly 

affect.the relative position of the rivers listed.

Names of streams have little hydrologic 

significance, even though they may be of great 

historic and geographic Interest. The rivers 

listed in table 2 bear the name of the stream 

at the mouth, "because this is the point of 

greatest flow. The river lengths given in the 

table and as shown on figure 2 represent not 

only the length of the stream bearing the given 

name, but the length of the river system, i.e., 

distance from mouth to the most upstream source 

as measured along the watercourse. For the 

Mississippi River, the length listed is the 

distance along the stream from the Gulf of 

Mexico to the source of Red Rock River in the

upper Missouri River Basin In western Montana.

The Mobile River, the eighth ranking river 

in table 2, is the name given to the meanderIng stream, some 38 miles long, which together 

with a parallel distributary, Tensaw River, 

carries the combined flow of the Alabama and 

Tombigbee Rivers to Mobile Bay.

Among the 26 large rivers listed In table 

2, only 9 are independent; that is, the rivers 

discharge directly into the ocean. The others, 

such as the Missouri and the Willamette, are 

tributary to larger streams included in the ' 

list. Some rivers, such as the Tennessee, are 

second-order tributaries, that is, tributary, 

to a tributary of a river that discharges into 

the ocean. Although It is" common practice to 

follow accepted names in deciding which river 

is a tributary and which is the main river, 

it Is largely a matter of historical accident 

which fork carries the name of the lower stream 

or Is separately named.

The outflow of all streams from the United 

States into the oceans or across its boundaries 

totals about 1,800,000 cubic feet per second. 

Of this total nearly 75 percent is accounted 

for by /the nine independent streams that appear 

in table 1. The remaining 25 percent Is discharged through a host of comparatively minor 

coastal streams.

We know only a little about rivers when 

we measure their lengths, drainage areas, and 

average flows. There is much to be learned 

about their range from flood to drought, about 

their sources, about their chemical quality 

and about their load of silt and the salts 

they carry in solution. The topography and 

climate as well as the vegetation growing in 

various parts of these river basins greatly 

affect stream flows and the character 6f our 

rivers. All these things must be known if we 

are to make most effective use of our rivers, 

large and small. Maps of all kinds, especially 

topographic maps which show elevations of all 

streams, mountains and plains, are a valuable 

aid in studying our rivers.

Information on these subjects is contained 

in the water-supply papers and topographic 

maps of the Geological Survey, available in 

major libraries. A list is available on request to the Director, Geological Survey, 

Washington 25, D. C. This report was arranged 

by W. B. Langbein and G. E. Harbeck, Jr ., with 

the assistance of other members of the staff 

of the Geological Survey.
Table 2.-Large rivers in the United States in order of average discharge at mouth 

(First order tributaries marked T, second order tributaries marked TT)

Rank

1

2

3

4

5

6

7

8

9

10

11

12

13

14

15

16

17

18

19

20

21

22

23

24

25

26

River

Mississippi

Ohio (T)

Columbia

St. Lawrence

Mississippi above

Missouri River (T)

Missouri (T)

Tennessee (TT)

Mobile

Red (T)

Arkansas (T)

Snake (T)

Susquehanna

Alabama (T)

White (T)

Willamette (T)

Wabash (TT)

Cumberland (TT)

Illinois (T)

Tombigbee (T)

Sacramento

Apalachicola

Pend Oreille (T)

Colorado

Hudson

Allegheny (TT)

Delaware

Length 

(miles )

a3 , 892

1,306

1,214

-

1,170

2,714

 900

758

1,300

1,450

1,038

444

720

690

270

475

720

420

525

382

500

490

fl,360

306

325

g390

Drainage 

area 

( s quare 

miles )

1,243,700

203,900

258,200

c302,000

171,600

529,400

40,600-

42,300

d91,400

160,500

109,000

27,570

22,600

28,000

11,250

33,150

18,080

27,900

19,500

e27,100

19,500

25,820

f 242, 900

13,370

11,700

g!2,300

Average 

discharge (1921-45) 

(cubic feet 

per second)

b620,000

255,000

235,000

c226,000

91,300

70,100

63,700

59,000

d57,300

45,200

44,500

35,800

31,600

-

30,700

30,400

27,800

27,400

27,000

-

25,000

24,600

-

21,500

19,200

19,000

Most distant 

source

Source of Red Rock

River, Mont.

Potter Co. , Pa.

Columbia Lake, B.C.

-

Lake Itasca, Hlnn.

Source of Red Rock

River, Mont.

Sift Virginia

NW. Georgia

Eastern edge of

New Mexico

Lake Co. , Colo.

Ocean Plateau,

Teton Co. , Wyo.

Otsego Lake ,

Otsego Co. , N. Y.

Jacks Creek, NW.

Georgia

Madison Co. , Ark.

Tumblebug Creek,

Douglas Co. , Oreg.

Darke Co. , Ohio

Poor Pork, Letcher

Co. , Ky.

Source of Kankakee

River, Joseph Co.,

Ind.

NE. Mississippi

Siskiyou Co. ,

Calif.

Towns Co. , Ga.

Near Butte , Mont.

Rocky Mountain National Park, Colo.

Essex Co. , N.y.

Potter Co. , Pa.

Source of West

Branch, Schoharie

'Co., N. Y.

Mouth

Gulf of Mexico.

Mississippi River.

Pacific Ocean.

-

Confluence with

Missouri River.

Mississippi River.

Ohio River.

Mobile, Bay.

Mississippi River.

Do.

Columbia River.

Chesapeake Bay.

Mobile River.

Mississippi River.

Columbia River.

Ohio River.

Do.

Mississippi River.

Mobile River.

Suisan Bay.

Gulf of Mexico.

Columbia River.

-

Upper New York Bay.

Ohio River.

Delaware Bay.

a The length from mouth to source of Mississippi River in Minnesota is 2,350 miles, 

b About 25 percent of the flow occurs in the Atchafalaya River, 

c At international boundary, lat. 45°. 

d Flow of Ouachita River has been added, 

e About.

f At Arizona-Sonora boundary; natural flow not accurately known because of large depletions 

for irrigation.

g At Deepwater Point on Delaware Bay.

The following rivers, mainly in the Southwest, have large drainage areas but relatively low 

average flows. They are listed according to drainage area, and are believed to discharge less than 

10,000 cfs. Colorado River above its junction with Green River in Utah is believed to be the largest in the group on a flow basis.

Square miles 

Rio Grande.................... 171,585

Platte River.................. 90,000

Kansas River.................. 61,300

Gila River.................... 58,100

Brazos River.................. 44,500

Green River (Utah-Wyo.)..............

Colorado River (Texas)...............

Pecos River..........................

Canadian River........................

Colorado River^ (above Green River)...

Square miles 

44,400 

41,500 

38,300 

29,700 

26,500

Yukon River, which rises in Canada and flows through Alaska to the Bering Sea, is estimated 

to have an average flow of about 150,000 cubic feet per second. It is about 2,300 miles long and 

drains an area of about 330,000 square miles.