AT THE TOP
The Green River headwaters rise at elevations of 13,400ft (4100m). in the Wind River Range of Wyoming. Flowing south, the river drain’s nearly 50,000 sq. miles of Wyoming, Utah and Colorado before joining its sister, the Colorado River in Canyonland’s National Park. The river flows a total of 730 miles while dropping no less than 9000ft (2743m). The Green is an exotic high desert river made famous in the American ethos by Native Tribes, beaver pelts and Major John Wesley Powell.
The river enjoys a rich mysterious history and has been known by different names and different people. Native Americans called the river Seedskadee-agie and the name was adopted by early trappers. In 1776 two Franciscan padres, Dominguez and Escalante, tried to establish an overland route from Santa Fe to missions in Monterey California. The two men encountered the Green near present day Jensen Utah and named it Rio San Buenaventura, or The River Saint of Good Fortune. Other early Spanish journals reference the river as Rio Verde but that name would become obsucre as waves of Spanish presence in the region would fall back. 50 years later General William Ashley would arrive in the Green River Basin to pursue riches in the fur trade. Although the origin of naming this river the Green is unclear, Ashley tends to be loosely credited for establishing and fixing the name in American history.
THE RIVER TODAY
Today more than 20 dams modify the Greens river system. Flaming Gorge has the greatest influence on the ecology and overall hydrograph dynamics. Several large tributaries feed into the Green below Flaming Gorge Dam (built in 1962 regulating 35% of the Greens drainage). The Yampa and the White drain northwest Colorado. The Duchesne, Price and San Rafael flow into the Green draining eastern Utah.
The Green River Basin has a long established history of human occupation. Starting with paleo and desert archaic hunter gatherers and later inhabited by native people’s we call the Fremont, who left their own distinct and colorful mark along the landscape. Following the Fremont are the Ute people, a proud and strong nation changed forever by the arrival of the horse and later, the greed of a fast growing nation. The Uintah Ute still reside in the Uinta basin and are the longest residents living in this region.
Dryland vegetation dominates most of the river basin. Big sage, black greasewood, pinyon, juniper, Indian rice grass & cheat grass can be found in wide spread mosaics. These areas receive low precipitation with an annual average of just 10 inches. Like all rivers in the Colorado Basin, the vast majority of discharge comes from winter precipitation arriving in the higher elevations and can vary widely between 70cm to 200cm (2.3ft to 6.5ft) of snowpack.
As with most Western river basins, land use along the basin is mostly agricultural. The Oil and Gas industry however has increased its presence in the watershed at an alarming rate. The two largest cities in the basin are Rock Springs Wyoming and Vernal Utah. Two cities are located on the banks of the Green, both share the rivers name.
Generally speaking the Green river can be divided into three reaches defined by the channel characteristics. Above Browns Park the riverbed is armored and can have closely grouped consistent temperature ranges year round due to the influence of Flaming Gorge Dam. Below the confluence of the Yampa, the Greens course meanders with a mild gradient, naturalized flow and sediment load. Below the White river the Greens' course remains mild in gradient including canyon segments of Desolation, Gray, Labyrinth and Stillwater up until its confluence with the Colorado and entry into Cataract canyon.
John Karl Hillers took this photo at the Green River Station in 1871. Decades before any dams or development the river has a long history of supporting human populations.