The Alabama River is the heart river of the state. It is named for the Indian tribe of the same name who occupied the area at the confluence of the Coosa and Tallapoosa rivers where the Alabama first forms. The name Alabama comes from the Choctaw word “alba,” plants or weeds and “amo,” to cut or to trim meaning to clear the land or thicket clearers.
The Alabama River is formed by the confluence of the Coosa and Tallapoosa Rivers just 15 miles north of Montgomery. The mighty river begins at the Fall Line, an imaginary line demarcating the area of Alabama’s ancient coastline (See landuse maps under Land Use). Whereas the lower portions of Alabama’s major tributaries, the Coosa and Tallapoosa fell rapidly over dramatic falls and shoals, the Alabama basin lies almost entirely within the rather flat topography of the coastal plain.
After the Alabama is formed it flows approximately 15 miles before reaching the city of Montgomery. This 15-mile section is the steepest in slope, falling rapidly at approximately 5 feet per mile. At Montgomery the river takes on more of its Coastal Plain characteristics and transitions gradually to a slope of .82 foot per mile. Below the fall line the slope is approximately .34 foot per mile (Corps, ’98).
The river’s total length is 315 miles and drains 22,168 square miles in 18 counties.
After its birth the river meanders in a generally westerly direction for 100 miles to Selma and then Southwesterly 210 miles before it joins the Tombigbee River. These two large basins, the Alabama and Tombigbee merge to form the Mobile River near the city of Calvert and then flow into Mobile Bay and the Gulf of Mexico. The Alabama River watershed (excluding its largest tributaries the Coosa, Tallapoosa and Cahaba) comprises an area of 6,023 square miles.
The Alabama serves as the unifier of Alabama’s Eastern Rivers, the Coosa and Tallapoosa and her western rivers, the Cahaba, Black Warrior and Tombigbee. (Keith)
Physical features of the Alabama are striking and have been formed and reformed in both geologic and modern times. Free-flowing, or unimpounded sections of the river show many High Bluffs formed as the chalky soils of the Black Belt were carved away. In other areas, annual spring floods used to drive the Alabama miles inland, inundating farms with rich topsoil. Before the construction of the Alabama’s lock and dam system, low water during the summer and fall months exposed shoals and sandbars making the river all but impossible to navigate. Where the river joins the Tombigbee, swamps and marshlands are common.
Much of the true quality of the Alabama River has been altered by three Army Corps of Engineers dam projects constructed in the 60s and 70s to facilitate navigation. Of the Alabama’s 315 mainstem river miles, 233 are impounded by these Corps Dams. These impoundments are formed by the Robert F. Henry, Millers Ferry and Claiborne lock and dams (see Hydrologic Modifications).
Large tributaries of the Alabama include Little River, Limestone, Pursley, Turkey, Pine Barren, Cedar, Mulberry, Boguechitto, Big Swamp, Pintlala, and Catoma creeks (See Tributaries).
The Alabama River Basin generally experiences a mild, humid climate, with usually mild, short winters and long, warm summers. Rainfall is abundant and distributed fairly uniformly throughout the year. Floods resulting from general storms inundate bottomlands along the principal streams on an average of from two to five times a year. Floods along smaller streams resulting from intense local storms are more frequent. Though the majority of floods are confined to low-lying undeveloped areas, there is considerable rural and urban flood damage.
Montgomery and Lowndes Counties are two of Alabama’s dryest counties receiving an annual rainfall of less than 52 inches.
In terms of water quantity the Alabama River has a carrying capacity that varies from 100,000 to 150,000 cfs. (Corps ’98)
The mainstem of the Alabama River flows through or borders 9 Alabama counties: Elmore, Autauga, Montgomery, Lowndes, Dallas, Wilcox, Monroe, Baldwin and Clarke. At the southernmost tip of Clarke county the river joins the Tombigbee to form the Mobile River.
Alabama River Dam Statistics
|Claiborne||Millers Ferry||Robert F. Henry|
|Length of Dam (feet)||1,016||994||912|
|Height of Dam (feet)||95.5||99.5||94|
|Clear Lock Dimensions (feet)||84 X 600||84 X 600||84 X 600|
|Minimum Depth Over Sills (feet)||13||13||13|
|Maximum Lift (feet)||30||48||45|
|Year Opened to Navigation||1969||1969||1972|
|Power Installation (KW)||None||75,000||68,000|
|Year Power On Line||None||1970||1975|
|Length of Lake (miles)||60.5||103||80.5|
|Area of Lake (acres)||5,930||17,200||12,510|
|Length of Shoreline (miles)||160||516||372|
Before the Coosa River enters Alabama and becomes one of the most utilized waters of the state, its watershed is born in the northwestern corner of Georgia (and a small piece of Tennessee) as several vital tributaries, the Conasauga, Coosawattee, Oostanaula and Etowah rivers.
As these headwater mountain streams converge the emerging river flows southwest along the valleys of the Blue Ridge Mountains and Cumberland Plateau, into Alabama and southward towards Montgomery. The river’s mainstem flows for a total length of 286 miles before arriving just north of Montgomery. About 255 the Coosa River’s mainstem rests in Alabama (89% of the total river miles.) (GA DNR)
The Coos River was, at one time, considered a winding river. One of the most famous sayings about the Coosa is that its bends “touched every farm in the state.” (Jackson)
The Coosa River watershed covers an enormous area of about 10,200 square miles, of which roughly 4,500 square miles (46%) lie in Georgia, and 5,400 square miles (53%) lie in Alabama. Less than 130 square miles (1%) of the watershed occurs in Tennessee. (GA DNR)
The Upper Basin is characterized by mountainous terrain sloping down to rolling hills and plateaus.
The Coosa River watershed occupies 5 different physiographic regions, each lending a unique character to these sections of the basin. The majority of the basin is split between the Valley and Ridge and Piedmont provinces in the upper and middle sections. 34% of the basin lies in the Valley and Ridge physiographic province with altitudes ranging from 600 to 1,600 feet in this region. Another 34% of the basin lies in the Piedmont province.
Only 4% of the land area lies in the Blue Ridge province of North Georgia and Tennessee. At the opposite end of the basin approaching its convergence with the Tallapoosa, 8% of watershed lies in the Cumberland Plateau in Alabama with altitudes of 1,500 to 1,800. Only 2% lies in the Coastal Plain. (Corps)
The Coosa River mainstem is formed when the Oostanaula and Etowah Rivers converge near Rome, Georgia. The drainage area of the upper Coosa tributaries above Rome covers approximately 4,000 square miles. (Corps) The Coosa then flows 286 miles from Rome to north of Montgomery where it joins the Tallapoosa to form the Alabama River.
The river falls approximately 420 feet in 267 miles, or 1.6 feet per mile. (Corps)
Seven Alabama Power Company dams form continuous impoundments over nearly the entire length of the Coosa River, with each dam discharging into the upper end of the next downstream impoundment. The first of these seven dams is located 60 miles below Rome and the last one 19 miles above the confluence with the Tallapoosa River (see Hyrdrologic Modifications).
The Coosa River channel varies from 300 to 500 feet wide, with banks 25 feet high along the flood plain.
The Chattooga River is the largest tributary to the Coosa with a drainage area of 675 square miles. (Corps)
Flows in the Coosa are about 15,000 cfs at Rome, and 50,000 cfs near Gadsden. (Corps)
Average precipitation ranges from 52 to 64 inches annually. Rainfall is greater in the Coosa River Basin than anywhere in the nation with the exception of two areas in the northwest states of Washington and Oregon. (Rivers of AL)
Coosa River Dam Statistics
|Walter Bouldin||Jordan||Mitchell||Lay||Logan Martin||H. Neely Henry||Weiss|
|Length of Dam (feet)||11,178||2,066||1,277||2,260||6,076||4,705||30,798|
|Height of Dam (feet)||120||125||106||129.6||97||104||126|
|Maximum Depth at Dam (feet)||52||110||90||88||69||53||62|
|Power Installation (KW)||225,000||100,000||170,000||177,000||128,250||72,900||87,750|
|Year Power On Line||1967||1928||1985||1914||1964||1966||1961|
|Length of Lake (miles)||3||18.4||14||48.2||48.5||77.6||52|
|Area of Lake (acres)||6,800||6,800||5,850||12,000||15,263||11,200||30,200|
|Length of Shoreline (miles)||118||118||147||289||275||339||447|
The most accepted meaning of Tallapoosa comes from the Choctaw or Alabama words for Tali which is rock and Pushi for pulverized. A less likely translation is from the Creek Talepula meaning stranger. (Read)
The Tallapoosa River originates in Paulding County Georgia, just 40 miles west of Atlanta, at an elevation of about 1,145 feet. It flows in a south-westerly direction for about 195 miles into Alabama and then takes a big left hand turn to the west after meeting Uphapee Creek and continues westerly for 40 miles to join the Coosa River near Wetumpka. Its total length of 235 miles drains a watershed area of 4,680 square miles. Only 720 square miles lie in Georgia accounting for 15% of the total land area. The remaining 3,960 square miles lie in Alabama accounting for 85% of the land area. (GA DNR)
From its source, the river falls at a rate of 12 feet per mile for the first 15 miles, then descends at a more gradual rate of 3.4 feet per mile. In the lower reach from Thurlow Dam to its mouth, the river falls at a rate of 1.6 feet per mile. (Corps) The river’s width varies from 250 feet to 700 feet and has banks that are 20 feet high along the flood plain. (GA DNR)
The Upper Tallapoosa has one primary tributary, the Little Tallapoosa River, which originates slightly to the south of its older sibling, in Carroll County Georgia. Within Georgia, the Tallapoosa River and the Little Tallapoosa River form separate basins of almost equal drainage area. The Little Tallapoosa’s total drainage area is 605 square miles. The main stem enters Alabama at Cleburne County and the Little Tallapoosa enters as the border between Cleburne and Randolph Counties. The two merge when they flow into Lake Wedowee. (GA DNR)
Other principal tributaries include Sougahatchee Creek, South Sandy Creek, Uphapee, and Hillabee Creeks in Alabama. (GA DNR)
71% of the basin lies in the Piedmont physiographic province. This area is characterized by igneous and metamorphic rocks, which together are called crystalline rocks. The metamorphic rocks are extensively folded and faulted. The other 29% of the basin lies in the Coastal Plain province with elevations between 50 and 850 feet (generally less than 300 feet) and a sediment based geology. (GA DNR)(Corps)
Riverflows in the watershed measure approximately 2,500 cfs (cubic feet per second) in the upper reaches of the river near Heflin, Alabama. At about the middle of the basin flows average 22,000 cfs at Wadley, Alabama, and near the mouth, below Thurlow Dam, flows measure approximately 60,000 cfs at Tallassee. (GA DNR)
The Tallapoosa River basin is characterized by a moist and temperate climate with annual precipitation ranging between 49 and 53 inches per year. There is minimal snowfall in the region and a distinct dry season occurs from mid-summer to late fall. Rainfall is usually greatest in March and least in October. The mean annual temperature is about 61 degrees Fahrenheit. (GA DNR)
Tallapoosa River Dam Statistics
|Length of Dam (feet)||1846||1,260||2,000||1,142|
|Height of Dam (feet)||62||87||168||150|
|Maximum Depth at Dam (feet)||54||46.5||155||135|
|Power Installation (KW)||58,000||37,000||55,200||135,000|
|Year Power On Line||1930||1928||1926||1983|
|Length of Lake (miles)||3||7.9||31||24|
|Area of Lake (acres)||574||2,000||41,150||10,660|
|Length of Shoreline (miles)||6||40||880||271|