The Colorado River is the 18th longest river in the United States. The United States of America —commonly referred to as the  and the longest river with both its source and mouth within Texas; however its drainage basin and some of its usually dry tributaries do extend into New Mexico. A delta is a Landform where the mouth of a River flows into an Ocean, Sea, Estuary, Lake or another river Texas ( is a state geographically located in the South Central United States and is also known as the Lone Star State. A drainage basin is an extent of Land where Water from Rain or Snow melt drains downhill into a body of water such as a River, A tributary is a Stream or River which flows into a mainstem (or parent river New Mexico ( is a state located in the southwestern region of the United States of America. The 862 mile long river flows generally southeast from Dawson County through Marble Falls, Austin, Bastrop, Smithville, La Grange, Columbus, Wharton, and Bay City before emptying into the Gulf of Mexico at Matagorda Bay. Dawson County is a County located in the US state of Texas. In 2000 its population was 14985 Marble Falls is a city in Burnet County, Texas, United States. Bastrop is a city and the County seat of Bastrop County, Texas, United States, located about thirty miles southeast of Austin it is Smithville is a city in Bastrop County, Texas, United States, near the Colorado River. La Grange is a city in Fayette County, Texas, United States, near the Colorado River. Columbus is a city in Colorado County, Texas, United States, 74 miles (119 km west of Houston along Interstate 10, on the Colorado Wharton is a city in Wharton County, Texas, United States. The population was 9237 at the 2000 Bay City is a City in Matagorda County, Texas, United States. The Gulf of Mexico ( Spanish: Golfo de México) is the ninth largest Body of water in the world TresPalaciosBayFromPorchjpg|thumb|200px|right|Matagorda Bay (Tres Palacios Bay as viewed from a porch in Palacios. 
The Colorado River, which means "colored red", was frequently confused with the not too distant to the north Brazos River by early Spanish explorers. The Brazos River, called the Rio de los Brazos de Dios by early Spanish explorers (translated as "The River of the Arms of God" is the 11th longest river in the  It is this confusion as well as an alleged mapping error that is believed to have led to its misnaming. The river is an important source of water for farming, cities, and electrical power production. Major man-made reservoirs on the river include Lake Buchanan, Inks Lake, Lake LBJ, Lake Marble Falls, Lake Travis, Lake Austin, and Lady Bird Lake in Austin. A reservoir is most broadly a place or hollow vessel where Fluid is kept in Reserve, for later use Lake Buchanan was formed by the construction of Buchanan Dam by the Lower Colorado River Authority to provide a water supply for the region and to provide Hydroelectric Inks Lake is a reservoir on the Colorado River in the Texas Hill Country in the United States. Lake Lyndon B Johnson (or Lake LBJ) is a reservoir on the Colorado River in the Texas Hill Country in the United States. Lake Marble Falls is a Reservoir on the Colorado River in the Texas Hill Country in the United States. Lake Travis is a reservoir on the Colorado River in central Texas in the United States. Lake Austin is a reservoir on the Colorado River in Austin Texas in the United States. Lady Bird Lake (formerly Town Lake) is a reservoir on the Colorado River in downtown Austin, Texas, in the United States Collectively, these lakes are known as the Highland Lakes. The Texas Highland Lakes is a chain of 6 man-made Lakes in Central Texas formed by several Dams on the Colorado River as it winds southeast In addition to power plants operating on each of the major lakes, waters of the Colorado are used for cooling the South Texas Nuclear Project, near Bay City. The South Texas Nuclear Generating Station, also known as the South Texas Project (STP is a Nuclear power station southwest of Bay City Texas, United States The Colorado River Municipal Water District owns and operates three reservoirs upstream of the Highland Lakes, Lake J. B. Thomas near Snyder, E. V. Spence Reservoir near Robert Lee, and O. H. Ivie Reservoir near Ballinger.
Flood control and use of the Colorado River is managed by two agencies established by the Texas Legislature, the Upper Colorado River Authority, and the Lower Colorado River Authority. The Texas Legislature is the state legislature of the US state of Texas. The Lower Colorado River Authority or LCRA is a Nonprofit public utility that was formed in 1934 by the Texas Legislature There are 11 major reservoirs along the Colorado River. 
The Colorado River also has made many geographic landmarks such as Deep Eddy Pool in Austin, Texas.