About 40 million people get water from the Colorado River . Studies show it’s drying up . Without changes in precipitation, the researchers said, for each additional 1.8 degrees of warming, the Colorado River’s average flow is likely to drop by about 9%.
That’s because the Colorado has been dammed and diverted in so many places that the river – which flowed from its headwaters high up on the Continental Divide to the Gulf for more than six million years – now slows to a trickle and dries up long before it reaches the sea.
The Colorado River is severely threatened by human overuse, environmental issues , and poor river management technique. As an extremely over-apportioned water resource, the water quality of the river is jeopardized by agricultural overdraw, which increases the salinity of the river.
Most — about 88 percent — of the total annual flow of water in the Lower Colorado River Basin originates upstream of Glen Canyon Dam (in northern Arizona) as a result of natural runoff from precipitation and melting snow in the mountains of Colorado , Wyoming, Utah and New Mexico.
The last time Lake Mead was full was 1983. Since then it has slowly declined. It is now 40 percent full: 1,082 feet above sea level. It may never be full again, experts say.
The water is running out . From 2000 to 2014, flows declined 19% from the 20th century average, according to American Geophysical Union Water Resources research. By 2100, the river flow could fall as much as 55%.
Phoenix and Tucson, Arizona , and Las Vegas , Nevada are the largest cities in the basin, and they use the Colorado River and its tributaries as their primary source of water. Water from the Colorado River is taken from its primary route and transported to locations far from the Colorado River Basin.
There are two Colorado Rivers in this world. There is the Colorado that everyone knows, having carved its way through millennia of rock to create the grandest of canyons. Then, there is the other Colorado ; it carves its way entirely through Texas. So far, its waters still flow to the Gulf of Mexico.
After coursing through its delta for nearly eight weeks, the fresh waters of the Colorado River have touched the high tides of the salty sea . Completing a 53-day journey through its Delta, the Colorado River reaches the tidal zone of the Sea of Cortez (Gulf of California).
In 1922, the states and the federal government created the Colorado River compact, which divided the Colorado River Basin into the Upper (Wyoming, Utah, Colorado , and New Mexico) and Lower (Nevada, California, and Arizona) Basin; each basin receiving 7.5 million MAF of water rights entitlements.
Recent studies have confirmed that the river’s steady decreased flow since 2000 is due to rising temperatures. The decline has amounted to 1.5 billion tons of missing water, equal to the annual water consumption of 10 million Americans, as The Washington Post reported.
About 238,600 square miles (618,000 km2), or 97 percent of the watershed, is in the United States. The river and its tributaries drain most of western Colorado and New Mexico , southwestern Wyoming , eastern and southern Utah , southeastern Nevada and California , and nearly all of Arizona .
Colorado River water is delivered to Mexico at Morelos Dam, located 1.1 miles downstream from where the California-Baja California land boundary intersects the river between the town of Los Algodones in northwestern Mexico and Yuma County, Ariz.
Instead of diverting the river’s last bit of water toward farm fields, the final dam on the Colorado River at the Mexican border lifted, and water inundated nearly 100 miles of the dry riverbed. It was called the pulse flow, meant to mimic a spring flood.
The water flows through and turns the turbines and then flows out into the Colorado River . Because the water intake is significantly below the surface of Lake Powell, the water coming out of the outflow is significantly colder than surface temperatures.