The Impending Demise of the Colorado River

As most people in the Western United States know, we are experiencing an extended drought. The aridness in the West has resulted in a severely diminished flow of water along the Colorado River. In fact, the river no longer discharges into the Sea of Cortez in Mexico. From that now dormant coastal estuary, most wildlife disappeared long ago. In 2022, with the advent of a limited pilot-program, a tiny amount of Colorado River water will flow again to the sea.

That is a hopeful sign during an otherwise bleak hydrological environment in the West. Ironically, humankind’s misplaced desire to control that once mighty river could result in a destructive wave traveling from Glen Canyon Dam all the way to the Sea of Cortez. Stay with me to the end of this article to learn how such an apocalyptic fate for the iconic river is possible.

Why is the Colorado River failing? Historical and updated river-flow data allows us to predict its demise. There is no longer an “if.” Now it is all about “when.” As less rain falls and the snowpack diminishes in the Upper Colorado River Basin, another phenomenon takes hold. For some it consists of blind ignorance. For many, it is the irrational human need to utilize and be wasteful of water. Either scenario raises demand for water, as if it emanates from an unlimited source.

One tankless water heater manufacturer promotes “endless hot water, which is now available” with their system. A nearby neighbor in Southern California defies current “one-day-each-week” outdoor watering limits. He runs his lawn sprinklers daily, often before sunrise to avoid detection, then follows up by hand-watering his entire front yard. Each day, almost ten gallons of potable water flows down the gutter past our house. Our front lawn is dead. His lawn is lush, green, and currently going to seed. In Southern California and now throughout the Southwest, a green lawn is the sure sign of a scofflaw. The attitude of many people throughout the Southwest, is one of entitlement. For them, cheating on their water budget or ignoring their legal limits is a way of life.

In the Upper Colorado River Basin, the drought now brings Lake Powell to its lowest elevation since initial filling in the 1960s. How low is it? In April 2022, the U.S. Bureau of Reclamation (USBR), which operates the major dams throughout the Colorado River system made a surprise announcement. From Flaming Gorge Reservoir, Wyoming’s largest, they released 500,000-acre-feet of water. From there, the water flowed down the Green River, and then into the Colorado River. The plan was to replenish and stabilize the water level in Lake Powell.

The USBR has touted this plan as a prudent way to keep power flowing from the hydroelectric turbines at Glen Canyon Dam, at least through 2023. Ironically, the original public proposal for the Glen Canyon Dam, promoted it as a “flood control dam,” not as a lynchpin in the electrical grid. Because the reservoir was beautiful and grand when at least half full, Lake Powell also became an indispensable recreational resource. Few people realized that the reservoir rested on soft and porous sandstone. In addition to relentless evaporation, the reservoir “banks” about fifteen percent of its water volume each year.

For almost fifty years, the coal-fired Navajo Generating Station (NGS) operated near the Glen Canyon Dam in Page, Arizona. Utilizing coal mined at Black Mesa, Arizona, its furnaces polluted the air, and its pumps withdrew vast quantities of water from Lake Powell. While wasting over ten percent of its power conveying its own cooling water and coal supply, NGS also broke records for sulfur dioxide and nitrogen oxide pollution. Although there was onsite wastewater recycling, losses due to both steam turbine generation and cooling tower evaporation made the NGS the largest single user of water in the Upper Colorado River Basin.

The main purpose of the NGS was to annually pump 50,000 acre-feet of “excess” Colorado River water over four mountain ranges to both Phoenix and Tucson, Arizona. Along the way, Arizona diverted vast amounts of water into shallow desert aquifers near the Palo Verde Nuclear Power Plant. The idea was to later mine that water from the desert and supply it to Phoenix. Currently, a large aqueduct is under construction there. Since the scheme has no precedent, no one knows if or for how long this desert water mining will work.

Despite the excessive air, water and ground pollution associated with the NGS, for decades it was like the monster that would not die. Not until the vast over development of natural gas resources in the Four Corners Region did the NGS's economic costs outweigh its job-related or power production benefits. In 2019, twenty years into a regional drought of millennial proportions, the NGS finally shutdown. If we are looking for a culprit in the current desiccated condition of Lake Powell, the NGS would be a prime target for investigation. In fact, the same flawed arguments that allowed the construction of Glen Canyon Dam go hand in hand with the commissioning of the NGS in the mid-1970s.

In 2022, all of us who now rely on the Colorado River have both an environmental and an economic bill to pay. How long can we collectively afford to subsidize lush green golf courses in Page, Arizona, alfalfa fields in the Imperial County, California, cotton growing in Pima County, Arizona, or my neighbor’s green lawn? More importantly, do humans have the capacity to create and implement a plan that will save the Colorado River system? Taking shorter showers, eliminating public fountains and decorative turf will not be enough to turn that tide.

What we need now is a clear-eyed look at the entire Colorado Riverway, from the high mountains to the low desert and everywhere in between. Affected states still adhere to the outdated Colorado River Compact of 1922. A century ago, all the states touching the Colorado River watershed agreed to over allocate its resources for generations to come. Politics played its role, with water rights assigned according to historical usage and population density. As a result, the compact granted the irrigation district in Imperial County, California (population 180,000), the largest single claim on Colorado River water. Why? Because long before huge dams and hydroelectric power allowed for the long-distance pumping of river water, inventive farmers directly tapped the river. In fact, a Colorado River dike which broke early in the 20th century resulted in the forming of the Salton Sea. Near Blythe, California resourceful farming families have succeeded in transforming the desert into cropland.

The Colorado River Compact expires in 2026. Often acrimonious discussions regarding its replacement are already underway. The participants include the Upper Basin (Colorado, New Mexico, Utah, and Wyoming), the Lower Basin (Arizona, California, and Nevada), Mexico and several tribal nations. According to a 2019 federal Drought Contingency Plan (DCP), as Lake Mead falls below 1,045’ elevation, the USBR must now declare a “Stage 2b Water Shortage Emergency”. On August 8, 2022, the reservoir stood at 1,229’ elevation, only four feet above a DCP Stage 3 declaration.

As a temporary measure, Congress recently approved $4 billion for emergency drought mitigation within the Colorado River Basin. Much of that money will go to pay Indian tribes and alfalfa growers in the Imperial Valley not to plant crops. The various USBR shortage decrees have flown by so quickly, it is hard for even the experts to keep track of water allocations. As of August 16, 2022, a Department of Interior declaration cut 2023 water allocations to Arizona by 21%, with smaller cuts to Nevada and Mexico. Senior water rights in California assured that there would be no cuts to its water deliveries in 2023.

In a surprise move, the Department of the Interior also allowed the acrimonious and unfruitful negotiations among the signatories to the “Law of the River” to proceed. It is an election year, and no one wanted to restrict anyone’s water rights further than already agreed upon. While Nero fiddled, Rome burned. While recalcitrant negotiators wrangle over cutting the allocations of others, but increasing their own, the Colorado River is not participating in the discussions.

Protracted negotiations or litigation will extend any true solution until it is too late to save hydroelectric production at both Glen Canyon and Hoover Dams. Achieving the “dead pool” elevation of 3,370’ at Lake Powell and 895’ at Lake Mead, when water can no longer pass through either dam, becomes more likely over time. Prior to dead pool, there will be too little water in the reservoirs to send down the penstocks and spin the electrical turbines. The USBR interim plan to “balance the two pools” will delay the inevitable, but not change the outcome.

In 2022 and 2023, a physical danger lurks in the “minimum power pool,” coming soon to Lake Powell. With typical 20th century hubris, the designers of Glen Canyon Dam did not anticipate a future time when its hydroelectric plant would go offline. As of September 6, 2022, Lake Powell was at an elevation of 3,523’, or almost seventy-eight feet lower than two years prior. The lake’s elevation rests just thirty-three feet above minimum power pool. At minimum power pool, there will not be sufficient "head" for gravity to send water down the penstocks and spin the turbines.

Unless weather patterns and water usage change drastically, that critical level will come sometime in 2023. Below minimum power pool, the reservoir will still have millions of acre-feet of sequestered water. What it will lack is a safe method of releasing any of that water through the dam. To fully grasp this eventuality, picture the Grand Canyon becoming a permanent dry wash. Still, a potentially unsafe method of water release from Glen Canyon Dam does exist. It involves what are known as “diversion tunnels” or the “outlet works.”

To facilitate construction of the dam in the 1950s, engineers first bored two enormous tunnels through the canyon walls. They then constructed a coffer dam, which temporarily diverted river water through the new diversion tunnels. The resulting outlet works could divert and convey even a large spring flood safely downstream. Luckily, no major floods occurred until after the 1964 commissioning of Glen Canyon Dam. Upon completion, crews dismantled the coffer dam, and closed the enormous gates at the head of the diversion tunnels.

All went well until the spring of 1983. In anticipation of summer electrical generation needs, the USBR kept Lake Powell at an elevated level. As spring wore on, there were huge snowstorms in the Upper Basin watershed, followed by rainstorms and rapid snow melt. Quickly, water in Lake Powell reached the top of the dam. Only hastily constructed plywood and lumber bulwarks atop the dam kept it from a disastrous overtopping. Unable to divert sufficient water through the hydroelectric plant, the operators “opened the floodgates,” better known as the outlet works.

For weeks, enormous outflows subjected the unlined sandstone tunnels to unanticipated stress. As a result, the outflow ejected huge chunks of raw sandstone downstream of the dam. Contemporary reports by persons not authorized to speak publicly told of the dam humming or thrumming, as if in major distress. Soon thereafter, the water level of Lake Powell dropped far enough to allow closure of the outlet works and resumption of water release solely through the hydroelectric station. Chastened, the dam’s operators never again let the lake rise even close to capacity prior to the end of spring runoff. Ironically, this conservative approach to reservoir management meant that Lake Powell would never again approach “full pool.”

The 2022 emergency release of water from Flaming Gorge Reservoir has bought the USBR one more year before the prospect of a minimum power pool at Lake Powell. In their version of Two Card Monte, dam operators are accepting 500,000 acre-feet of water from Flaming Gorge and reducing deliveries downstream to Lake Mead by a similar amount. As Oz famously said in the Wizard of Oz, “Pay no attention to the man behind the curtain.” Likewise, should we pay no attention to the huge amount of water retained in Lake Powell?

If you were to write a disaster movie script, you would include a scene in which veteran Glen Canyon Dam workers face the prospect of reopening the compromised outlet works. In releasing any remaining water from Lake Powell to Lake Mead, they fear the cracking and ultimate destruction of Glen Canyon Dam. In the next scene, they would open the creaking gates of the outlet works. For a time, everything would work correctly. Then, they would hear a low harmonic sound emanating from the dam. Soon, the humming would become a roar. Too late to save themselves, the workers would run for the exits, only to have the dam disintegrate around them.

The result would be the immediate draining of the second largest reservoir in America. Almost immediately, the biggest flood on the Colorado River since the creation of the Grand Canyon would ensue. At Lake Mead, downstream, the wave would surge to a height greater than any tsunami in history. As the surge created by the wave would impinge on Hoover Dam, that too would disintegrate. Farther downstream, the remaining dams would fall one after another. Within hours, the once sequestered contents of the Colorado River would rush into the Sea of Cortez, creating a saltwater tsunami.

Such a catastrophe cannot happen, you say. In 1983, the dam almost failed. There is nothing to say that our next attempt to save the Colorado River will not result in its untimely demise. Thousands of years hence, descendants of survivors in the Southwest might tell tales of a Great Flood, from which their ancestors survived. Other than not including an ark full of animals, that story has a familiar ring.

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