By Tom Ribe
The new year opens with large areas of Australia on fire. Americans might dismiss this nightmare as distant and affecting places most have never been. In reality the disaster in Australia (16 million acres burned so far) is a major wake up call for humanity all over the world. In Indonesia (not that far from Australia) record rainfall flooded the country at levels never before recorded and killed 60 people – last week. In the US, we can all point to changes in our local weather some gradual, others extreme. But the consequences of global heating will be extremely serious for millions of people and if anything, we see that scientific predictions of how the climate crisis will unfold have been too conservative. Look at the Colorado River for example.
The Colorado River mostly flows through remote places, through deserts and canyons after gathering its waters from the mountains of Wyoming and Colorado. It cuts the Grand Canyon and backs up behind two massive dams on either end of the Grand Canyon – Glen Canyon Dam and Hoover Dam. Then the water steps though more dams as it heads to California. Along the way water is siphoned off in huge quantities to feed Tucson, Phoenix, Las Vegas and the cotton fields of Arizona.
Downstream in California the water goes to grow dates and alfalfa in the Imperial Valley and it provides a vast amount of water for the ever growing cities around Los Angeles. The Colorado River used to empty in the Gulf of California but once Mexico takes its share, the delta there is dry.
We’ve replumbed the arid west to prop up areas like Denver that are too dry to support their growing populations. Huge pipes move water from the Colorado River Basin to the Denver area across mountain ranges and pipes move water from the Colorado River Basin into the Chama River in New Mexico, largely to supply Albuquerque, making New Mexico a customer of the Colorado River’s diminishing water resources. Southern Utah interests want to build new diversion pipes to drain Colorado water into desert agriculture and swelling population areas.
Around 40 million people depend on the Colorado River for their water supply yet the Colorado River is shrinking away before our eyes. The two big storage dams on the Colorado, Lake Powell and Lake Mead are at their lowest levels since 1963. Lake Powell is only 52% full and the more critical Lake Mead is 46% full even after high snowfall and runoff in 2019.
The Colorado River Basin is in an 18 year long drought, just as climate change models predict. Models predict that the Southwest overall will continue to dry and warm as climate change deepens. Colorado River managers on the state and federal level have been developing “interim” plans to deal with low flows, assuming that the river will return to the levels it was running at in 1922 when allocations of water to the various states were made – in a high water year.
Yet the drought is not temporary and the river will continue to drop. Already Lake Powell is very close to being too low for its electricity generating turbines to continue spinning. (Once it drops 175 more feet the turbines go off.) The states upstream have promised to cut water use, drain reservoirs in places like Gunnison, Colorado and prop up Lake Powell. Their reasons for doing this involve the complications of the water allocation systems agreed to over the decades since 1922. Needless to say, empty reservoirs in Wyoming, New Mexico, and Colorado may not make local residents happy but we can see that the river is shrinking and its reservoirs are drying up.
Vast amounts of water are wasted on landscaping in arid cities and even more water is wasting growing feed for cattle in Arizona and California, a hugely inefficient use of water. Those alfalfa fields use large amounts of water, most lost to evaporation. These hugely thirsty crops can be grown in Iowa or Kentucky. Yet this waste of water is a sacred cow in the West and the farmers who evaporate water off their fields for luxury foods like beef will lobby hard to be exempted from the pain that is spreading across the Basin.
For example the 50 mile long Imperial Valley in extreme inland southern California gets about 3 inches of rain per year and its groundwater is not suitable for domestic or agricultural use. All of its water for vast fields of alfalfa and lettuce come from the Colorado River through three large canals. The area is below sea level and has senior water rights to the metropolitan water users in California. Thus cattle feed gets water before people in southern California.
Back upstream of the Grand Canyon, Glen Canyon Dam looms 700 feet above the desert, its arching concrete walls braced against the impoundments of Colorado River water of yesteryear. The reservoir peaked in 1983 when the dam nearly failed in huge floods, its spillways blowing out chunks of concrete and sandstone while its managers frantically extended the top of the dam. Since then the reservoir has drained away as new water flows diminish. The Glen Canyon Institute and others have been calling for the abandonment of the dam so the water can flow on to raise Lake Mead below Grand Canyon National Park. There are many indications that such abandonment will happen in the next decade.
When it does, Glen Canyon Dam, now managed by the US Bureau of Reclamation, will become a monument to hubris and the ambitions of our society to conquer the desert Southwest. The National Park Service manages the Lake Powell and the associated Glen Canyon National Recreation Area. We can imagine that the dam itself will be designated a national historic site with rangers giving tours of the forever silent electrical turbines, the tunnels, the office suits frozen in time.
The drying of the Colorado River Basin cannot be underestimated as one of the great unfolding disasters of global warming. We cannot manufacture water and short of massive diversions from the Great Lakes, it is impossible to know where water to feed the millions of people in Arizona, Nevada and southern California will come from. Without water, these cities are uninhabitable. As the water supply shrinks, the sociology of these city’s decline will be a wrenching experience for American democracy.
