Colorado drainage basins

The Gunnison River in the Black Canyon.

Main article: Geography of Colorado

See also: List of rivers in Colorado

The U.S State of Colorado includes the headwaters of several important rivers. The state is divided generally East to West by the Continental Divide. East of the Continental Divide, surface waters flow via the North Platte River, the South Platte River, the Republican River, the Arkansas River, the Cimarron River, the Canadian River, or the Rio Grande to the Gulf of Mexico. West of the Continental Divide, surface waters flow via the Green River, the upper Colorado River^[1] (formerly the Grand River), or the San Juan River into the Colorado River and on to the Gulf of California. Colorado also has three significant endorheic basins: the San Luis Closed Basin in the San Luis Valley, and the Bear Creek Basin and the White Woman Basin spanning the Colorado-Kansas border south and north of the Arkansas River.

Table of major drainage basins

Major Drainage Basins of the State of Colorado

Basin	Outlet	Total Area[2]	In-State Area[2]	% In-State[2]
Colorado River[1]	Gulf of California	001703,132 km2 271,481 mi2	001100,195 km2 38,686 mi2	A06414.2%
Arkansas River	Mississippi River	002478,501 km2 184,750 mi2	00270,022 km2 27,036 mi2	A06314.6%
Rio Grande	Gulf of Mexico	003457,275 km2 176,555 mi2	00912,070 km2 4,660 mi2	A0722.6%
Canadian River	Arkansas River	004122,701 km2 47,375 mi2	073154 km2 59 mi2	A0730.1%
Green River[1][3]	Colorado River	005115,903 km2 44,750 mi2	00527,340 km2 10,556 mi2	A05923.6%
North Platte River	Platte River	00680,755 km2 31,180 mi2	0185,129 km2 1,980 mi2	A0686.4%
upper Colorado River (Grand River)[1]	Colorado River	00767,993 km2 26,252 mi2	00357,680 km2 22,270 mi2	A03884.8%
San Juan River	Colorado River	00864,560 km2 24,927 mi2	00815,175 km2 5,859 mi2	A06023.5%
South Platte River	Platte River	00962,738 km2 24,223 mi2	00448,948 km2 18,899 mi2	A04078.0%
Smoky Hill River	Kansas River	01051,783 km2 19,994 mi2	0402,493 km2 963 mi2	A0704.8%
Cimarron River	Arkansas River	01144,890 km2 17,332 mi2	0165,481 km2 2,116 mi2	A06612.2%
Yampa River	Green River	01221,506 km2 8,304 mi2	00715,289 km2 5,903 mi2	A04371.1%
Gunnison River[4]	upper Colorado River (Grand River)	01320,851 km2 8,051 mi2	00620,851 km2 8,051 mi2	A001100%
North Fork Republican River	Republican River	01413,172 km2 5,086 mi2	01011,522 km2 4,449 mi2	A03787.5%
White River	Green River	01512,989 km2 5,015 mi2	0129,796 km2 3,782 mi2	A04275.4%
Dolores River	upper Colorado River (Grand River)	01611,998 km2 4,633 mi2	01110,619 km2 4,100 mi2	A03688.5%
Laramie River	North Platte River	01711,961 km2 4,618 mi2	061989 km2 382 mi2	A0678.3%
Little Snake River	Yampa River	01810,629 km2 4,104 mi2	0224,412 km2 1,704 mi2	A05241.5%
Purgatoire River	Arkansas River	0198,923 km2 3,445 mi2	0138,601 km2 3,321 mi2	A03196.4%
Lodgepole Creek	South Platte River	0208,374 km2 3,233 mi2	069496 km2 191 mi2	A0695.9%
Rio Chama	Rio Grande	0218,204 km2 3,168 mi2	071238 km2 92 mi2	A0712.9%
San Luis Closed Basin[5]	endorheic basin	0227,638 km2 2,949 mi2	0147,638 km2 2,949 mi2	A002100%
Frenchman Creek	Republican River	0237,398 km2 2,856 mi2	0362,539 km2 980 mi2	A05334.3%
South Fork Republican River	Republican River	0247,195 km2 2,778 mi2	0175,454 km2 2,106 mi2	A04175.8%
San Luis Creek	San Luis Closed Basin	0257,000 km2 2,703 mi2	0157,000 km2 2,703 mi2	A003100%
Cache la Poudre River	South Platte River	0264,959 km2 1,915 mi2	0214,587 km2 1,771 mi2	A03492.5%
Bear Creek Basin	endorheic basin	0274,896 km2 1,890 mi2	0372,521 km2 973 mi2	A04851.5%
Huerfano River	Arkansas River	0284,840 km2 1,869 mi2	0194,840 km2 1,869 mi2	A004100%
Big Sandy Creek	Arkansas River	0294,825 km2 1,863 mi2	0204,825 km2 1,863 mi2	A005100%
Bear Creek	Bear Creek Basin	0304,500 km2 1,737 mi2	0392,500 km2 965 mi2	A04755.6%
North Fork Cimarron River	Cimarron River	0314,462 km2 1,723 mi2	0432,225 km2 859 mi2	A04949.9%
Arikaree River	North Fork Republican River	0324,429 km2 1,710 mi2	0234,265 km2 1,647 mi2	A03296.3%
San Miguel River	Dolores River	0334,060 km2 1,567 mi2	0244,060 km2 1,567 mi2	A006100%
Stinking Water Creek	Frenchman Creek	0343,862 km2 1,491 mi2	063966 km2 373 mi2	A05825.0%
Roaring Fork River	upper Colorado River (Grand River)	0353,766 km2 1,454 mi2	0253,766 km2 1,454 mi2	A007100%
Crow Creek	South Platte River	0363,717 km2 1,435 mi2	0442,201 km2 850 mi2	A04659.2%
Horse Creek	Arkansas River	0373,680 km2 1,421 mi2	0263,680 km2 1,421 mi2	A008100%
Ladder Creek	Smoky Hill River	0383,645 km2 1,407 mi2	067663 km2 256 mi2	A06218.2%
Bijou Creek	South Platte River	0393,612 km2 1,395 mi2	0273,612 km2 1,395 mi2	A009100%
White Woman Basin	endorheic basin	0403,577 km2 1,381 mi2	065908 km2 351 mi2	A05725.4%
Rush Creek	Arkansas River	0413,570 km2 1,378 mi2	0283,570 km2 1,378 mi2	A010100%
Animas River	San Juan River	0423,562 km2 1,375 mi2	0302,971 km2 1,147 mi2	A03983.4%
Saguache Creek	San Luis Creek	0433,482 km2 1,345 mi2	0293,482 km2 1,345 mi2	A011100%
Montezuma Creek	San Juan River	0443,044 km2 1,175 mi2	062983 km2 380 mi2	A05432.3%
White Woman Creek	White Woman Basin	0453,000 km2 1,158 mi2	066800 km2 309 mi2	A05626.7%
Beaver Creek	South Platte River	0462,939 km2 1,135 mi2	0312,939 km2 1,135 mi2	A012100%
Uncompahgre River	Gunnison River	0472,921 km2 1,128 mi2	0322,921 km2 1,128 mi2	A013100%
Tomichi Creek	Gunnison River	0482,874 km2 1,109 mi2	0332,874 km2 1,109 mi2	A014100%
Apishapa Creek	Arkansas River	0492,798 km2 1,080 mi2	0342,798 km2 1,080 mi2	A015100%
Saint Vrain Creek	South Platte River	0502,572 km2 993 mi2	0352,572 km2 993 mi2	A016100%
Eagle River	upper Colorado River (Grand River)	0512,515 km2 971 mi2	0382,515 km2 971 mi2	A017100%
Vermillion Creek	Green River	0522,500 km2 965 mi2	0591,155 km2 446 mi2	A05146.2%
North Fork Gunnison River	Gunnison River	0532,492 km2 962 mi2	0412,492 km2 962 mi2	A018100%
Fountain Creek	Arkansas River	0542,418 km2 933 mi2	0422,418 km2 933 mi2	A019100%
Big Thompson River	South Platte River	0552,149 km2 830 mi2	0452,149 km2 830 mi2	A020100%
Two Butte Creek	Arkansas River	0562,107 km2 814 mi2	0462,107 km2 814 mi2	A021100%
Mancos River	San Juan River	0572,099 km2 810 mi2	0471,973 km2 762 mi2	A03394.0%
Conejos River	Rio Grande	0582,078 km2 802 mi2	0561,471 km2 568 mi2	A04470.8%
North Fork Smoky Hill River	Smoky Hill River	0591,965 km2 759 mi2	064947 km2 366 mi2	A05048.2%
Sidney Draw	South Platte River	0601,949 km2 753 mi2	070368 km2 142 mi2	A06118.9%
South Fork Beaver Creek	Beaver Creek	0611,939 km2 749 mi2	068522 km2 201 mi2	A05526.9%
Sand Arroyo Creek	North Fork Cimarron River	0621,938 km2 748 mi2	0571,314 km2 507 mi2	A04567.8%
Chico Creek	Arkansas River	0631,934 km2 747 mi2	0481,934 km2 747 mi2	A022100%
Kiowa Creek	South Platte River	0641,888 km2 729 mi2	0491,888 km2 729 mi2	A023100%
Pawnee Creek	South Platte River	0651,875 km2 724 mi2	0501,875 km2 724 mi2	A024100%
McElmo Creek	San Juan River	0661,842 km2 711 mi2	0531,654 km2 639 mi2	A03589.8%
Blue River	upper Colorado River (Grand River)	0671,770 km2 683 mi2	0511,770 km2 683 mi2	A025100%
Piedra River	San Juan River	0681,770 km2 683 mi2	0521,770 km2 683 mi2	A026100%
Piceance Creek	White River	0691,630 km2 629 mi2	0541,630 km2 629 mi2	A027100%
Little Beaver Creek	Beaver Creek	0701,602 km2 619 mi2	072210 km2 81 mi2	A06513.1%
Clear Creek	South Platte River	0711,497 km2 578 mi2	0551,497 km2 578 mi2	A028100%
Taylor River	Gunnison River	0721,258 km2 486 mi2	0581,258 km2 486 mi2	A029100%
Boulder Creek[6]	Saint Vrain Creek	0731,160 km2 448 mi2	0601,160 km2 448 mi2	A030100%
Cherry Creek	South Platte River	0731,050 km2 405 mi2	0601,050 km2 405 mi2	A030100%

See also

• hydrology
  • surface-water hydrology
    • drainage basin
• State of Colorado
  • Geography of Colorado
    • List of rivers in Colorado

References

1. ^ ^{a b c d} The Colorado River was originally considered to begin at the confluence of the Green River and the Grand River in what is now Canyonlands National Park in Utah. Thus, the namesake river of the State of Colorado did not flow through that state. On 1921-07-25, House Joint Resolution 460 of the 66th United States Congress changed the name of the Grand River to the Colorado River over the objections of the U.S. Geological Survey, which noted that the drainage basin of the Green River was more than 70% more extensive than that of the Grand River.
2. ^ ^{a b c} Gustafson, Daniel L. (2003-01-24). "Hydrologic Unit Project". Montana State University, Environmental Statistics Group. http://www.esg.montana.edu/gl/huc/. Retrieved 2008-02-05. 
3. ^ The headwaters of the Green River are located in the Wind River Mountains of the State of Wyoming.
4. ^ The Gunnison River Basin is the most extensive river basin exclusively within the State of Colorado.
5. ^ The San Luis Closed Basin is the most extensive endorheic basin in the State of Colorado.
6. ^ Murphy, Sheila F. (2006) (PDF). State of the watershed: Water quality of Boulder Creek, Colorado. U.S. Department of the Interior, U.S. Geological Survey. ISBN 1-411-30954-5. http://pubs.usgs.gov/circ/circ1284/pdf/circ1284.pdf. Retrieved 2008-02-05. 

External links

• State of Colorado website
  • Colorado Division of Natural Resources
    • Colorado Water Conservation Board
    • Colorado Division of Water Resources
    • Colorado Geological Survey
      • Major Rivers of Colorado
    • Colorado's Decision Support Systems
• Colorado Watersheds
• Colorado Hydrologic Units