Green River (Colorado River tributary)
The Green River, located in the western United States, is the chief tributary of the Colorado River. The watershed of the river, known as the Green River Basin, covers parts of the U.S. states of Wyoming, Utah, and Colorado. The Green River is 730 miles (1,170 km) long, beginning in the Wind River Mountains of Wyoming and flowing through Wyoming and Utah for most of its course, except for a short segment of 40 miles (64 km) in western Colorado. Much of the route traverses the arid Colorado Plateau, where the river has carved some of the most spectacular canyons in the United States. The Green is slightly smaller than Colorado when the two rivers merge but typically carries a larger load of silt. The average yearly mean flow of the river at Green River, Utah is 6,121 cubic feet (173.3 m3) per second.
The Green River near Canyonlands National Park
Upper Green River, Wyoming
The Green River flows through Split Mountain Canyon before leaving Dinosaur National Monument in a meandering path across a broad irrigated flood plain
Green River, Wyoming, by Thomas Moran, 1878
The Colorado River is one of the principal rivers in the Southwestern United States and in northern Mexico. The 1,450-mile-long (2,330 km) river, the 5th longest in the United States, drains an expansive, arid watershed that encompasses parts of seven U.S. states and two Mexican states. The name Colorado derives from the Spanish language for "colored reddish" due to its heavy silt load. Starting in the central Rocky Mountains of Colorado, it flows generally southwest across the Colorado Plateau and through the Grand Canyon before reaching Lake Mead on the Arizona–Nevada border, where it turns south toward the international border. After entering Mexico, the Colorado approaches the mostly dry Colorado River Delta at the tip of the Gulf of California between Baja California and Sonora.
The Colorado River at Horseshoe Bend, Arizona, a few miles below Glen Canyon Dam
Headwaters of the Colorado River in Rocky Mountain National Park, Colorado
Colorado River in the Grand Canyon seen from Pima Point, near Hermit's Rest
Colorado River as it exits the United States into Mexico beneath the San Luis Colorado-Colonia Miguel Aléman Bridge (September 2009)