According to tree ring scientists from the University of Arizona in Tuscon, the Colorado River went through a six decade long drought during the mid-1100s. This drought was longer than any other drought know to the region. The Colorado River is essential to the American Southwest, draining into about 242,000 square miles of land to include seven U.S. states: Arizona, California, Colorado, Nevada, New Mexico, Utah, and Wyoming. “The Intergovernmental Panel on Climate Change predicted in a recent report that the Southwestern U.S. Will become hotter and drier as the climate warms.” With human caused climate change and run off reduction, it has been predicted that the Colorado River could become dry by 2012. Discussions in this paper will include a general history and how the American Southwest relies on the Colorado River for survival, how climate change is effecting it, and management efforts to curtail conflicts between vying interests over a shared water source.
Figure 1. Map of the Colorado River
THE COLORADO RIVER
The Colorado River is located in the southwestern United States and northwestern Mexico. It is 1,450 miles long with its headwaters in the Rocky Mountain National Park in Estes Park, Colorado. Geologically, the Colorado River begins near Moab, Utah, at the junction of the Green River,which is the primary tributary for the Colorado. (Until 1921, the Colorado River did not “technically” begin until the Grand and Green Rivers joined together in Utah. In that year the Grand River was renamed as the Colorado River, at the request of the State of Colorado.) It then flows south out of Wyoming, and the Grand River, and southwest out of Colorado. Below this point, the river takes on a reddish tint that earned it the name Colorado, or red-colored, because of suspended reddish silt in the water. Today the color of the river is more of a blue-green though, due to the creation of the Glen Canyon Dam in 1963. The silt and sediments that gave the river its reddish-brown color are now trapped behind the dam at the bottom of Lake Powell.
Before the construction of the Glen Canyon Dam, the Colorado river could carry around 500,000 tons of silt and sediment per day through the Grand Canyon. The peak flow rate before the dam was normally around 85,000 cfs (abbreviation for "cubic feet per second" which is used to measure river flow rates). The peak flow rate after construction was reduced to 30,000 cfs. The reduction in cfs resulted in a smaller distribution of the iconic red-colored silt and sediment. The main reason for the creation of the Glen Canyon Dam was to stop silt from building up behind Hoover Dam. The construction of the dam has had a negative impact on the Grand Canyon environment. The flash floods that at one time scrubbed the canyon clean and deposited fresh sand along the beaches no longer occurs. The water temperature used to get as warm as 80 degrees F. It is now icy-cold year round...