Originally a high flow, sediment-rich river with relatively warm waters, the 1,450-mile long river and its tributaries have been broken up by dams. The Colorado River Plateau drains 242,900 square miles of basin and range land between the Rocky Mountains and the Sierra Nevada Mountains. The river, whose every ounce of water is counted and allocated, once flowed freely to the Gulf of California. There are reports of Spanish explorers sailing upstream from the gulf during the mid 1500s.
That is no longer the case. The river is dammed a number of times and provides water for irrigation and consumption to Colorado, Wyoming, Utah, Idaho, California, Nevada, Arizona and New Mexico.
Glen Canyon Dam, Hoover Dam, Davis Dam and Parker Dam all created recreational lakes that supply critical water supplies to thirsty neighbors. Lake Powell, Lake Mead, Lake Mojave and Lake Havasu, respectively, were created above the dams.
These lakes are some of the largest manmade lakes in the world, and certainly within the U.S. Lake Havasu is the deepest dam in the world with 73 percent of its structure below water.
The Colorado is one of three major Utah rivers with whitewater rapids. Where the Colorado runs through Cataract Canyon is considered one of the best rapid runs in the country.
And many people extol the beauty of floating through the Grand Canyon.
The section of the Green River where it runs past Flaming Gorge National Recreation Area is another highly-regarded rafting spot that sports Class 1 and Class II whitewater.
Further down, where it feeds into Dinosaur National Monument the rapids offer Class I to Class IV rides. Keep floating downriver to Desolation and Gray Canyons, that, together feature 60 rapids from Class I to Class III.
The gentlest major river is the San Juan, which runs past remote petroglyphs and wildlife and offers Class II to III rapids. The river still flows red, like the Colorado once did.
The Dirty Devil River flows through Glen Canyon and into Lake Powell and is the melding of the Fremont River and Muddy Creek just north of Hanksville. Butch Cassidy loved using its tributaries to hide from the law.
The banks and canyons of the isolated Yampa River in Colorado was another favorite hideout for Butch Cassidy and his Hole in the Wall Gang. The river runs through Dinosaur National Monument and some of the most scenic territory in the region. The Yampa is the only major tributary of the Colorado that is undammed. The last 46 miles is extraordinary, providing one of the U.S.'s top 10 toughest rapid experiences before it flows into the Green River. The Yampa offers only 300 private permits per year and gets 2,500 applications that are allocated by lottery.
The Provo River is a favorite fly fishing destination. It meanders through the middle of Heber Valley between flowing from the Uinta Mountains and into Utah Lake.