Currents Newsletter -- Did you know?

The two Colorado Rivers
Two rivers, one name, many differences (and some similarities)

The Colorado River in Texas empties into Matagorda Bay, as seen in this video. The Colorado River in the western United States empties into the Gulf of California.

One river flows through eight states, the other only through one. One river flows into the Gulf of California, the other into the Gulf of Mexico. One river is reddish in color, like its name. The other flows relatively clear, despite its name. The two rivers have little in common other than sharing a name: Colorado.

Yes, the United States has two Colorado rivers: one in the American West, one in Texas. Even so, there is a widespread perception that one Colorado River jumps the Continental Divide and detours through Texas on its way west.

Folks who e-mail LCRA, asking for good whitewater locations in the Grand Canyon, are often amazed when informed of the distinction. “Why don’t you call it the Texas River?” asked one e-mailer after learning that the Texas Colorado is the largest river entirely within the state.

LCRA came along too late to claim naming rights. Those belonged to Alonso De León, an explorer of Spanish Texas, who used the name “ Colorado” as early as 1690. Unfortunately, he may have intended it for another river: the Brazos, which actually is reddish in color. The theory is that early mapmakers, not terribly keen on detail, transposed the two names.

Meanwhile, early Spanish settlers along that other river, noting the water’s reddish color, started calling it the Colorado – and the name for both rivers was well established by the time they both became part of the United States.

Both rivers do have one thing in common – many people and communities depend on their waters to meet a variety of needs. There are so many claims on the western Colorado’s waters that occasionally the river is reduced to a trickle – or dries up completely – before reaching its mouth at the Gulf of California. The Texas Colorado flows consistently into the Gulf of Mexico, and LCRA is working to ensure that it stays that way.

For more about the differences – and some similarities – of the two Colorado rivers, check out this nifty comparison.

Two Colorado Rivers at a Glance

	The Colorado River (Western U.S.)	The Colorado River (Texas)

Source of Name	Reddish color of river, thanks to sediment deposits	May be a misnomer, thanks to lack of attention to detail by Spanish mapmakers. The river's waters generally run clear
First Called "Colorado"	1776, by Father Francesco Garces	1690, by Alonso De Leon, explorer and provincial governor
Length	1,450 miles	862 miles
Comparison of Length to Other U.S. Rivers	7th longest in U.S.	18th longest in U.S.
Source	Colorado: Rocky Mountain National Park	West Texas: Dawson County, south of Lubbock
Mouth	Gulf of California, in northwestern Mexico, south of Yuma, Arizona	Matagorda Bay, Gulf of Mexico, southeast of Bay City
Drainage area	246,000 square miles	42,300 square miles
Elevation Range	Almost 9,000 feet from its headwaters in Colorado to the Gulf of California	About 3,000 feet from Dawson County to Gulf of Mexico
Average Annual Flow	17.5 million acre-feet	1.2 million acre-feet (based on inflows into Highland Lakes)
No. of States in Drainage Area	Seven (Arizona, California, Colorado, Nevada, New Mexico, Wyoming)	One (Texas). While a few sources say a tiny portion of drainage area is in New Mexico, most reliable sources cite the Colorado as the longest river entirely in Texas
Most Notable Landmark	The Grand Canyon (which it created)	Texas State Capitol (which it didn't create -- though the location of the capital city, Austin, was chosen in 1839 in part for its "abundant natural resources," including the Colorado River)
Major Dams	10, including Glen Canyon and Hoover dams	10, including Buchanan and Mansfield dams
Best-Known Reservoirs	Lake Powell and Lake Mead	The Highland Lakes, especially Lake Travis
Total Population Served	17 million	3 million
Major Cities Served	Phoenix, Tucson, Las Vegas, Los Angeles, San Diego, Denver, Albuquerque	Austin
Hydroelectric Generation Capacity	4,178 megawatts	285.5 megawatts
Whitewater Rafting Locations	At least four, including the Grand Canyon	None (unless it's flooding)
Amount of Water Used for Irrigation	Two-thirds to 90 percent	About two-thirds
Greatest Water Quality Problem	Salinity (from soil, rocks and evaporation) and siltation	Nonpoint-source pollution, from urban and rural land use
Good Popcorn Movie Involving the Colorado River	"Rio Grande" (1950), the last of John Ford's cavalry trilogy, with army officer John Wayne battling the Apaches and his family. Maureen O'Hara plays his disgruntled wife. The Colorado River plays the Rio Grande (the movie was filmed near Moab, Utah)	"Outlaw Blues" (1977), in which Peter Fonda and Susan St. James end a chase around Austin by jumping their boat over Tom Miller Dam. (Inks Dam plays the role of Tom Miller Dam)
Sources: World Almanac; Texas Almanac; Handbook of Texas; U.S. Geological Survey; WaterEncyclopedia.com; Colorado River Water Users Association; Encarta; Wikipedia; Utah Division of Water Resources; Waterknowledge.Colostate.edu; Utah.com; DesertUSA.com; Amazon.com; Turner Classic Movies; LCRA