Divisions Mississippi River

1 divisions

1.1 upper mississippi
1.2 middle mississippi
1.3 lower mississippi

divisions

the mississippi river can divided 3 sections: upper mississippi, river headwaters confluence missouri river; middle mississippi, downriver missouri ohio river; , lower mississippi, flows ohio gulf of mexico.

upper mississippi

the beginning of mississippi river @ lake itasca (2004)



mississippi head of navigation, st. anthony falls



confluence of wisconsin , mississippi rivers, viewed wyalusing state park in wisconsin

the upper mississippi runs headwaters confluence missouri river @ st. louis, missouri. divided 2 sections:

the source of upper mississippi branch traditionally accepted lake itasca, 1,475 feet (450 m) above sea level in itasca state park in clearwater county, minnesota. name itasca chosen designate true head of mississippi river combination of last 4 letters of latin word truth (veritas) , first 2 letters of latin word head (caput). however, lake in turn fed number of smaller streams.

from origin @ lake itasca st. louis, missouri, waterway s flow moderated 43 dams. fourteen of these dams located above minneapolis in headwaters region , serve multiple purposes, including power generation , recreation. remaining 29 dams, beginning in downtown minneapolis, contain locks , constructed improve commercial navigation of upper river. taken whole, these 43 dams shape geography , influence ecology of upper river. beginning below saint paul, minnesota, , continuing throughout upper , lower river, mississippi further controlled thousands of wing dikes moderate river s flow in order maintain open navigation channel , prevent river eroding banks.

the head of navigation on mississippi coon rapids dam in coon rapids, minnesota. before built in 1913, steamboats go upstream far saint cloud, minnesota, depending on river conditions.

the uppermost lock , dam on upper mississippi river upper st. anthony falls lock , dam in minneapolis. above dam, river s elevation 799 feet (244 m). below dam, river s elevation 750 feet (230 m). 49-foot (15 m) drop largest of mississippi river locks , dams. origin of dramatic drop waterfall preserved adjacent lock under apron of concrete. saint anthony falls true waterfall on entire mississippi river. water elevation continues drop steeply passes through gorge carved waterfall.

after completion of st. anthony falls lock , dam in 1963, river s head of navigation moved upstream, coon rapids dam. however, locks closed in 2015 control spread of invasive asian carp, making minneapolis once again site of head of navigation of river.

the upper mississippi has number of natural , artificial lakes, widest point being lake winnibigoshish, near grand rapids, minnesota, on 11 miles (18 km) across. lake onalaska, created lock , dam no. 7, near la crosse, wisconsin, more 4 miles (6.4 km) wide. lake pepin, natural lake formed behind delta of chippewa river of wisconsin enters upper mississippi, more 2 miles (3.2 km) wide.

by time upper mississippi reaches saint paul, minnesota, below lock , dam no. 1, has dropped more half original elevation , 687 feet (209 m) above sea level. st. paul st. louis, missouri, river elevation falls more slowly, , controlled , managed series of pools created 26 locks , dams.

the upper mississippi river joined minnesota river @ fort snelling in twin cities; st. croix river near prescott, wisconsin; cannon river near red wing, minnesota; zumbro river @ wabasha, minnesota; black, la crosse, , root rivers in la crosse, wisconsin; wisconsin river @ prairie du chien, wisconsin; rock river @ quad cities; iowa river near wapello, iowa; skunk river south of burlington, iowa; , des moines river @ keokuk, iowa. other major tributaries of upper mississippi include crow river in minnesota, chippewa river in wisconsin, maquoketa river , wapsipinicon river in iowa, , illinois river in illinois.

the upper mississippi largely multi-thread stream many bars , islands. confluence st. croix river downstream dubuque, iowa, river entrenched, high bedrock bluffs lying on either side. height of these bluffs decreases south of dubuque, though still significant through savanna, illinois. topography contrasts lower mississippi, meandering river in broad, flat area, flowing alongside bluff (as @ vicksburg, mississippi).

the confluence of mississippi (left) , ohio (right) rivers @ cairo, illinois, demarcation between middle , lower mississippi river


middle mississippi

the mississippi river known middle mississippi upper mississippi river s confluence missouri river @ st. louis, missouri, 190 miles (310 km) confluence ohio river @ cairo, illinois.

the middle mississippi relatively free-flowing. st. louis ohio river confluence, middle mississippi falls 220 feet (67 m) on 180 miles (290 km) average rate of 1.2 feet per mile (23 cm/km). @ confluence ohio river, middle mississippi 315 feet (96 m) above sea level. apart missouri , meramec rivers of missouri , kaskaskia river of illinois, no major tributaries enter middle mississippi river.

lower mississippi

lower mississippi river near new orleans

the mississippi river called lower mississippi river confluence ohio river mouth @ gulf of mexico, distance of 1,000 miles (1,600 km). @ confluence of ohio , middle mississippi, long-term mean discharge of ohio @ cairo, illinois 281,500 cubic feet per second (7,970 cubic metres per second), while long-term mean discharge of mississippi @ thebes, illinois (just upriver cairo) 208,200 cu ft/s (5,900 m/s). thus, volume, main branch of mississippi river system @ cairo can considered ohio river (and allegheny river further upstream), rather middle mississippi.

in addition ohio river, major tributaries of lower mississippi river white river, flowing in @ white river national wildlife refuge in east central arkansas; arkansas river, joining mississippi @ arkansas post; big black river in mississippi; , yazoo river, meeting mississippi @ vicksburg, mississippi. widest point of mississippi river in lower mississippi portion exceeds 1 mile (1.6 km) in width in several places.

deliberate water diversion @ old river control structure in louisiana allows atchafalaya river in louisiana major distributary of mississippi river, 30% of mississippi flowing gulf of mexico route, rather continuing down mississippi s current channel past baton rouge , new orleans on longer route gulf. although red river commonly thought tributary, not, because water flows separately gulf of mexico through atchafalaya river.