The Gunnison River in Black Canyon of the Gunnison National Park.
|- left||Tomichi Creek, Lake Fork Gunnison River, Cimarron River, Uncompahgre River|
|- right||Smith Fork, North Fork Gunnison River|
|Cities||Gunnison, Grand Junction|
|- elevation||8,008 ft (2,441 m) |
|- elevation||4,553 ft (1,388 m) |
|Length||180 mi (290 km) |
|Basin||7,928 sq mi (20,533 km2) |
|Discharge||for Near Grand Junction|
|- average||2,570 cu ft/s (72.8 m3/s) |
|- max||35,200 cu ft/s (996.8 m3/s)|
|- min||106 cu ft/s (3 m3/s)|
The Gunnison River is a tributary of the Colorado River, 164 miles (264 km) long, in the Southwest state of Colorado. It is the fifth largest tributary of the Colorado River, with a mean flow of 4320 ft³/s (122 m³/s).
The Gunnison River is formed by the confluence of Taylor and East rivers at Almont in eastern Gunnison County. Just past the town of Gunnison, the river begins to swell into the expanse of Blue Mesa Reservoir, a 36-mile (58 km) long reservoir formed by Blue Mesa Dam, where it receives the Lake Fork of the Gunnison. Just downstream it is dammed again to form Morrow Point Reservoir, then just downstream of that dam for the final time to form Crystal Reservoir. The reservoirs produce hydroelectric power and supply water for the surrounding areas for both municipal and irrigation use. The reservoirs are the upper part of the Black Canyon of the Gunnison, one of the longest, narrowest, and deepest gorges in the world. Below Crystal Dam it begins to roar through massive cataracts and flows through the deepest part of the gorge. At the outlet of the canyon it receives the North Fork River, then downstream near Delta, Colorado is joined by the Uncompahgre River. It then winds through desert canyonlands, where it receives Kannah Creek before it empties out of the Dominguez Canyon into the Colorado in Grand Junction, some years rivaling the Colorado River for equal if not slightly less volume.
The Gunnison River ranges in width from 100 to 1,000 feet (30 to 300 m) and 3 to 50 feet (1 to 15 m) in depth. The river's powerful current and many rapids make upstream travel nearly impossible. It is navigable for small craft throughout its course and by larger boats below the Black Canyon. Parts of the Black Canyon are unnavigable to any sorts of craft because of giant cataracts[clarification needed]. Navigation through the entire canyon is dangerous and for experienced boaters only.
The first non-native to see and record information of the Gunnison River was Juan Maria de Rivera, who came to the banks of the river just below its confluence with the Uncompahgre River in 1761 and 1765. It was again seen in 1776 by Silvestre Vélez de Escalante. At the time the Spanish name for the river was Rio de San Javier (Xavier), and the Native American name was Tomichi. Escalante noted that Rivera thought it was "the great Rio del Tizon", the long used Spanish name for the lower Colorado River.
The river is named for U.S. Army Captain John W. Gunnison of the Topographic Engineers who was ambushed and killed by Pahvant Utes while mapping a trail west in Utah Territory in 1853.
Part of the river's water is diverted to irrigate the Uncompahgre Valley via the 5 miles (8 km) long Gunnison Tunnel, which was built between 1905 and 1909. Dams on the river include Blue Mesa Dam, Morrow Point Dam, and Crystal Dam.
- Google Earth elevation for GNIS coordinates.
- U.S. Geological Survey Geographic Names Information System: Gunnison River, USGS GNIS.
- Gunnison River, The Columbia Gazetteer of North America. 2000.
- Water Data Report, Colorado 2003, from Water Resources Data Colorado Water Year 2003, USGS.
- U.S. Geological Survey. National Hydrography Dataset high-resolution flowline data. The National Map, accessed March 18, 2011
- Escalante's journal